Introduction

This Project Guide provides engine data and system proposals for the early design phase of marine engine
installations. For contracted projects specific instructions for planning the installation are always delivered.
Any data and information herein is subject to revision without notice.
This 1/2002 issue replaces all previous issues of the Wärtsilä 20 Project Guides. Numerous revisions have been
made. Also the structure of this Project Guide has been amended.

Wärtsilä Finland Oy
Marine & Licensing
Application Technology

Vaasa, January 2002

THIS PUBLICATION IS DESIGNED TO PROVIDE AS ACCURATE AND AUTHORITIVE INFORMATION REGARDING THE SUBJECTS COVERED AS WAS
AVAILABLE AT THE TIME OF WRITING. HOWEVER, THE PUBLICATION DEALS WITH COMPLICATED TECHNICAL MATTERS AND THE DESIGN OF
THE SUBJECT AND PRODUCTS IS SUBJECT TO REGULAR IMPROVEMENTS, MODIFICATIONS AND CHANGES. CONSEQUENTLY, THE PUBLISHER
AND COPYRIGHT OWNER OF THIS PUBLICATION CANNOT TAKE ANY RESPONSIBILITY OR LIABILITY FOR ANY ERRORS OR OMISSIONS IN THIS
PUBLICATION OR FOR DISCREPANCIES ARISING FROM THE FEATURES OF ANY ACTUAL ITEM IN THE RESPECTIVE PRODUCT BEING DIFFERENT
FROM THOSE SHOWN IN THIS PUBLICATION. THE PUBLISHER AND COPYRIGHT OWNER SHALL NOT BE LIABLE UNDER ANY CIRCUMSTANCES,
FOR ANY CONSEQUENTIAL, SPECIAL, CONTINGENT, OR INCIDENTAL DAMAGES OR INJURY, FINANCIAL OR OTHERWISE, SUFFERED BY ANY
PART ARISING OUT OF, CONNECTED WITH, OR RESULTING FROM THE USE OF THIS PUBLICATION OR THE INFORMATION CONTAINED
THEREIN.

COPYRIGHT © 2001 BY WÄRTSILÄ FINLAND OY

ALL RIGHTS RESERVED. NO PART OF THIS PUBLICATION MAY BE REPRODUCED OR COPIED IN ANY FORM OR BY ANY MEANS, WITHOUT PRIOR
WRITTEN PERMISSION OF THE COPYRIGHT OWNER.

Marine Project Guide W20 - 1/2002 i

 Table of Contents

Table of Contents
1. General data and outputs . . . . . . . . . . . . . . . . . . . 1 12. Turbocharger and air cooler cleaning . . . . . . . . 79
1.1. Technical main data . . . . . . . . . . . . . . . . . . . . . . . . . 1 12.1. Turbine cleaning system (5Z03) . . . . . . . . . . . . . . . 79
1.2. Maximum continuous output . . . . . . . . . . . . . . . . . . 1
1.3. Reference conditions . . . . . . . . . . . . . . . . . . . . . . . . 1 13. Exhaust emissions . . . . . . . . . . . . . . . . . . . . . . . . 80
1.4. Principal dimensions and weights . . . . . . . . . . . . . . 4 13.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
13.2. Diesel engine exhaust components . . . . . . . . . . . . 80
2. Operating ranges . . . . . . . . . . . . . . . . . . . . . . . . . . 6 13.3. Marine exhaust emissions legislation. . . . . . . . . . . 81
2.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 13.4. Methods to reduce exhaust emissions . . . . . . . . . 82
2.2. Matching the engines with driven equipment . . . . . 7
2.3. Loading capacity . . . . . . . . . . . . . . . . . . . . . . . . . . 12 14. Automation system . . . . . . . . . . . . . . . . . . . . . . . 84
2.4. Ambient conditions . . . . . . . . . . . . . . . . . . . . . . . . 13 14.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
14.2. Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3. Technical data tables . . . . . . . . . . . . . . . . . . . . . . 14 14.3. Safety System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
14.4. Speed Measuring (8N03) . . . . . . . . . . . . . . . . . . . . 85
4. Description of the engine . . . . . . . . . . . . . . . . . . 24 14.5. Sensors & signals. . . . . . . . . . . . . . . . . . . . . . . . . . 86
4.1. Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 14.6. Local instrumentation. . . . . . . . . . . . . . . . . . . . . . . 88
4.2. Main components . . . . . . . . . . . . . . . . . . . . . . . . . 24 14.7. Control of auxiliary equipment . . . . . . . . . . . . . . . . 88
4.3. Cross sections of the engine . . . . . . . . . . . . . . . . . 26 14.8. Speed control (8I03). . . . . . . . . . . . . . . . . . . . . . . . 89
4.4. Overhaul intervals and expected life times . . . . . . 27 14.9. Microprocessor based engine control system (WECS)
(8N01). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
5. Piping design, treatment and installation . . . . . 28
5.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 15. Electrical power generation and management 105
5.2. Pipe dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 15.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
5.3. Trace heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 15.2. Electric power generation . . . . . . . . . . . . . . . . . . 106
5.4. Pressure class . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 15.3. Electric power management system (PMS) . . . . . 108
5.5. Pipe class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 15.4. Typical one line main diagrams . . . . . . . . . . . . . . 111
5.6. Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
5.7. Local gauges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 16. Foundation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
5.8. Cleaning procedures . . . . . . . . . . . . . . . . . . . . . . . 31 16.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
5.9. Flexible pipe connections . . . . . . . . . . . . . . . . . . . 31 16.2. Steel structure design . . . . . . . . . . . . . . . . . . . . . 113
16.3. Mounting of main engines . . . . . . . . . . . . . . . . . . 113
6. Fuel oil system . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 16.4. Mounting of generating sets . . . . . . . . . . . . . . . . 119
6.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 16.5. Reduction gear foundations. . . . . . . . . . . . . . . . . 123
6.2. MDF installations . . . . . . . . . . . . . . . . . . . . . . . . . . 33 16.6. Free end PTO driven equipment foundations . . . 123
6.3. HFO installations . . . . . . . . . . . . . . . . . . . . . . . . . . 39 16.7. Flexible pipe connections . . . . . . . . . . . . . . . . . . 123
7. Lubricating oil system . . . . . . . . . . . . . . . . . . . . . 49 17. Vibration and noise . . . . . . . . . . . . . . . . . . . . . . 124
7.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 17.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
7.2. Lubricating oil quality . . . . . . . . . . . . . . . . . . . . . . . 49 17.2. External forces and couples. . . . . . . . . . . . . . . . . 124
7.3. Internal lubricating oil system. . . . . . . . . . . . . . . . . 51 17.3. Mass moments of inertia . . . . . . . . . . . . . . . . . . . 125
7.4. External circulating oil system . . . . . . . . . . . . . . . . 52 17.4. Air borne noise . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
7.5. Separation system . . . . . . . . . . . . . . . . . . . . . . . . . 53
7.6. Filling, transfer and storage . . . . . . . . . . . . . . . . . . 53 18. Power transmission . . . . . . . . . . . . . . . . . . . . . . 126
7.7. Crankcase ventilation system . . . . . . . . . . . . . . . . 53 18.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
7.8. Flushing instructions . . . . . . . . . . . . . . . . . . . . . . . 54 18.2. Connection to alternator . . . . . . . . . . . . . . . . . . . 126
7.9. System diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . 55 18.3. Flexible coupling . . . . . . . . . . . . . . . . . . . . . . . . . 127
18.4. Clutch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
8. Compressed air system . . . . . . . . . . . . . . . . . . . . 57 18.5. Shaftline locking device and brake . . . . . . . . . . . 127
8.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 18.6. Power-take-off from the free end. . . . . . . . . . . . . 128
8.2. Compressed air quality . . . . . . . . . . . . . . . . . . . . . 57 18.7. Torsional vibration calculations . . . . . . . . . . . . . . 129
8.3. Internal starting air system . . . . . . . . . . . . . . . . . . . 57 18.8. Turning gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
8.4. External starting air system . . . . . . . . . . . . . . . . . . 58
19. Engine room layout . . . . . . . . . . . . . . . . . . . . . . 130
9. Cooling water system . . . . . . . . . . . . . . . . . . . . . 61 19.1. Crankshaft distances . . . . . . . . . . . . . . . . . . . . . . 130
9.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 19.2. Space requirements for maintenance . . . . . . . . . 133
9.2. Internal cooling water system . . . . . . . . . . . . . . . . 62 19.3. Handling of spare parts and tools . . . . . . . . . . . . 133
9.3. External cooling water system . . . . . . . . . . . . . . . . 65 19.4. Required deck area for service work . . . . . . . . . . 133
9.4. Example system diagrams . . . . . . . . . . . . . . . . . . . 70
20. Transport dimensions and weights . . . . . . . . . 134
10. Combustion air system . . . . . . . . . . . . . . . . . . . . 75 20.1. Lifting of engines . . . . . . . . . . . . . . . . . . . . . . . . . 134
10.1. Engine room ventilation . . . . . . . . . . . . . . . . . . . . . 75 20.2. Engine components . . . . . . . . . . . . . . . . . . . . . . . 135
10.2. Combustion air quality . . . . . . . . . . . . . . . . . . . . . . 75
10.3. Combustion air system design. . . . . . . . . . . . . . . . 75 21. Dimensional drawings . . . . . . . . . . . . . . . . . . . . 137

11. Exhaust gas system . . . . . . . . . . . . . . . . . . . . . . . 77 22. ANNEX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

11.1. Internal exhaust gas system. . . . . . . . . . . . . . . . . . 77 22.1. Ship inclination angles . . . . . . . . . . . . . . . . . . . . . 138
11.2. External exhaust gas system . . . . . . . . . . . . . . . . . 77 22.2. Unit conversion tables . . . . . . . . . . . . . . . . . . . . . 139
22.3. Collection of drawing symbols used in drawings. 142
22.4. Notes for the CD-ROM. . . . . . . . . . . . . . . . . . . . . 143

ii Marine Project Guide W20 - 1/2002

 1. General data and outputs

1. General data and outputs

1.1. Technical main data Note!
The Wärtsilä 20 is a 4-stroke, non-reversible, turbocharged The minimum nominal speed is 1000 RPM both for instal-
and intercooled diesel engine with direct injection of fuel. lations with controllable pitch and fixed pitch propellers.
Table 1.1. Rating table for main engines
Cylinder bore 200 mm
Stroke 280 mm Engine Output in kW (BHP) at 1000 RPM
Piston displacement 8.8 l/cyl kW (BHP)
Number of valves 2 inlet valves and
4L20 720 980
2 exhaust valves
5L20 825 1120
Cylinder configuration 4, 5, 6, 8, 9, in-line
Direction of rotation Clockwise, counter- 6L20 1080 1470
clockwise on request 8L20 1440 1960
9L20 1620 2200
1.2. Maximum continuous
output The maximum fuel rack position is mechanically limited to
100% of the continuous output for main engines.
The mean effective pressure Pe can be calculated as fol-
lows: The permissible overload is 10% for one hour every twelve
hours. The maximum fuel rack position is mechanically
P[kW] · c · 1.2 · 109 limited to 110% continuous output for auxiliary engine.
Pe [bar] = The alternator outputs are calculated for an efficiency of
D2 · L · n · cyl · p
0.95 and a power factor of 0.8.

where: 1.3. Reference conditions

Pe = mean effective pressure [bar]
The output is available up to a charge air coolant tempera-
P = output per cylinder [kW]
ture of max. 38°C and an air temperature of max. 45°C. For
n = engine speed [r/min] higher temperatures, the output has to be reduced accord-
D = cylinder diameter [mm] ing to the formula stated in the ISO standard.
L = length of piston stroke [mm]
cyl = number of cylinders
c = operating cycle (4)

Table 1.2. Rating table for auxiliary engines

Engine Output at
720 RPM/60 Hz 750 RPM/50 Hz 900 RPM/60 Hz 1000 RPM/50 Hz
Engine Generator Engine Generator Engine Generator Engine Generator
(kW) (kVA) (kW) (kVA) (kW) (kVA) (kW) (kVA)
4L20 520 620 540 640 680 810 720 855
5L20 775 920 825 980
6L20 780 930 810 960 1020 1210 1080 1280
8L20 1040 1240 1080 1280 1360 1615 1440 1710
9L20 1170 1390 1215 1440 1530 1815 1620 1925

Marine Project Guide W20 - 1/2002 1

 1. General data and outputs

The specific fuel consumption is stated in the chapter for • air temperature 25°C
Technical data with the reference for the engine driven • relative humidity 30%
equipment and the effect they have on the specific fuel
consumption. The statement applies to engines operating • charge air coolant temperature 25°C
in ambient conditions according to ISO 3046-1 : 1995(E). For other than ISO 3046-1 conditions the same standard
gives correction factors on the fuel oil consumption.
• total barometric pressure 100 kPa

1.3.1. Fuel characteristics

Table 1.3. MDF Specifications

Property Unit ISO-F-DMX ISO-F-DMA ISO-F-DMB ISO-F-DMC 1) Test method ref.

Viscosity, min., before injection pumps 2) cSt 1.8 1.8 1.8 1.8 ISO 3104
Viscosity, max. cSt at 40°C 5.5 6 11 14 ISO 3104
Viscosity, max, before injection pumps 2) 24 24 24 24 ISO 3104
kg/m³ at ISO 3675 or
Density, max. 3) 890 900 920
15°C 12185
ISO 5165 or
Cetane number 45 40 35 —
4264
Water, max. % volume — — 0.3 0.3 ISO 3733
Sulphur, max. % mass 1 1.5 2 2 ISO 8574
Ash, max. % mass 0.01 0.01 0.01 0.05 ISO 6245
Vanadium, max. mg/kg — — — 100 ISO 14597
Sodium before engine, max. 2) mg/kg — — — 30 ISO 10478
Aluminium + Silicon, max. mg/kg — — — 25 ISO 10478
Aluminium + Silicon before engine, max. 2) mg/kg — — — 15 ISO 10478
Carbon residue (micro method, 10 % vol
% mass 0.30 0.30 — — ISO 10370
dist.bottoms), max.
Carbon residue (micro method), max. % mass — — 0.30 2.50 ISO 10370
Flash point (PMCC), min. 2) °C 60 60 60 60 ISO 2719
Pour point, max. 4) °C — -6 - 0 0–6 0–6 ISO 3016
Sediment % mass — — 0.07 — ISO 3735

1) Use of ISO-F-DMC category fuel is allowed provided that the fuel treatment system is equipped with a fuel centrifuge.
2) Additional properties specified by the engine manufacturer, which are not included in the ISO specification or differ from
the ISO specification.
3) In some geographical areas there may be a maximum limit.
4) Different limits specified for winter and summer qualities.
Lubricating oil, foreign substances or chemical waste, hazardous to the safety of the installation or detrimental to the perfor-
mance of the engines, should not be contained in the fuel.

2 Marine Project Guide W20 - 1/2002

 1. General data and outputs

The fuel specification “HFO 2" is base on the ISO This tighter specification is an alternative and by using
8217:1996(E) standard and covers the fuel categories this specification, longer overhaul intervals of specific
IS-F-RMA10 - RMK55. Additionally, the engine manu- engine components are possible. See table in the chapter
facturer has specified the fuel specification ”HFO 1". for Description of the engine.
Table 1.4. HFO Specifications

Property Unit Limit HFO 1 Limit HFO 2 Test method ref.

Viscosity, max. cSt at 50°C 55 55 ISO 3104
cSt at 100°C 730 730
Redwood No. 1 s 7200 7200
at 100°F
Density, max. kg/m³ at 15°C 991 1)/1010 991 1)/1010 ISO 3675 or 12185
CCAI, max.4) 850 870 2) ISO 8217
Water, max. % volume 1.0 1.0 ISO 3733
Water before engine, max.4) % volume 0.3 0.3 ISO 3733
Sulphur, max. % mass 2.0 5.0 ISO 8754
Ash, max. % mass 0.05 0.20 ISO 6245
Vanadium, max. mg/kg 100 600 3) ISO 14597
Sodium, max.4) mg/kg 50 100 3) ISO 10478
Sodium before engine, max.4) mg/kg 30 30 ISO 10478
Aluminium + Silicon, max. mg/kg 30 80 ISO 10478
Aluminium + Silicon before engine, max.4) mg/kg 15 15 ISO 10478
Conradson carbon residue, max. % mass 15 22 ISO 10370
Asphaltenes, max.4) % mass 8 14 ASTM D 3279
Flash point (PMCC), min. °C 60 60 ISO 2719
Pour point, max. °C 30 30 ISO 3016

1) Max. 1010 kg/m³ at 15°C provided the fuel treatment system can remove water and solids.
2) Straight run residues show CCAI values in the 770 to 840 range and are very good ignitors. Cracked residues delivered as
bunkers may range from 840 to - in exceptional cases - above 900. Most bunkers remain in the max. 850 to 870 range at the
moment.
3) Sodium contributes to hot corrosion on exhaust valves when combined with high sulphur and vanadium contents. So-
dium also contributes strongly to fouling of the exhaust gas turbine blading at high loads. The aggressiveness of the fuel de-
pends not only on its proportions of sodium and vanadium but also on the total amount of ash constituents. Hot corrosion
and deposit formation are, however, also influenced by other ash constituents. It is therefore difficult to set strict limits
based only on the sodium and vanadium content of the fuel. Also a fuel with lower sodium and vanadium contents that
specified above, can cause hot corrosion on engine components.
4) Additional properties specified by the engine manufacturer, which are not included in the ISO specification.

Lubricating oil, foreign substances or chemical waste, hazardous to the safety of the installation or detrimental to the perfor-
mance of the engines, should not be contained in the fuel.
The limits above also correspond to the demands of the following standards. The properties marked with 4) are not specifi-
cally mentioned in the standards but should also be fulfilled.
• BS MA 100: 1996, RMH 55 and RMK 55 • CIMAC 1990, Class H55 and K55
• ISO 8217: 1996(E), ISO-F-RMH 55 and RMK 55

Marine Project Guide W20 - 1/2002 3

 1. General data and outputs

1.4. Principal dimensions and

weights
Main engines (3V92E0068b)

Engine A* A B* B C* C D E F G H I K
4L20 2510 1348 1483 1800 325 725 1480 155 718 980
5L20 2833 1423 1567 1800 325 725 1780 155 718 980
6L20 3254 3108 1528 1348 1580 1579 1800 325 624 2080 155 718 980
8L20 3973 3783 1614 1465 1756 1713 1800 325 624 2680 155 718 980
9L20 4261 4076 1614 1449 1756 1713 1800 325 624 2980 155 718 980

Weight
Engine M* M N* N P* P R* R S* S T* T
**
4L20 854 665 920 248 694 349 7.2
5L20 938 688 1001 328 750 370 7.8
6L20 951 950 589 663 1200 971 328 328 762 763 273 343 9.3
8L20 1127 1084 708 738 1224 1000 390 390 907 863 325 339 11
9L20 1127 1084 696 731 1224 1000 390 390 907 863 325 339 11.6
* Turbocharger at flywheel end
** Weights (in Metric tons) with liquids (wet sump) but without flywheel

4 Marine Project Guide W20 - 1/2002

 1. General data and outputs

Auxiliary engines (3V58E0576a)

Weight
ENGINE A* B* C D* E* F* G* H* I K* L* M
[ton]
4L20 4910 4050 665 2460 728 990 1270 1770 1800 1580 2338 1168 14.0
5L20 5190 3945 688 2430 728 1075 1270 1770 1800 1580 2458 1329 15.1
895/ 1270/ 1770/ 1800 1580/ 2243/
6L20 5290 4540 663 2300 728 1299 16.8
975 1420 1920 1730 2323
1420 / 1920/ 1730/
8L20 6010 5080 731 2310 728 1025 1800 2474 1390 20.7
1570 2070 1880
1075/ 1570/ 2070/ 1800 1880/ 2524/
9L20 6550 5415 731 2580 728 1390 23.8
1125 1800 2300 2110 2574
* Values are based on standard alternator, whose type (water or air cooled) and size affects to width, length, height and weight.
Weight is based on wet sump engine with engine liquids.

Marine Project Guide W20 - 1/2002 5

 2. Operating ranges

2. Operating ranges
2.1. General sions, lower fuel consumption and SCR compatibility also
contribute to the restriction of the operating field.
The available operating field of the engine depends on the
required output, and these should therefore be determined A matter of high importance is the matching of the propel-
ler and the engine. Weather conditions, acceleration, the
together. This applies to both FPP and CPP applications.
loading condition of the ship, draught and trim, the age and
Concerning FPP applications also the propeller matching
must be clarified. fouling of the hull, and ice conditions all play an important
role.
A diesel engine can deliver its full output only at full engine
speed. At lower speeds the available output and also the With a FP propeller these factors all contribute to moving
the power absorption curve towards higher thermal load-
available torque are limited to avoid thermal overload and
ing of the engine. There is also a risk for surging of the
turbocharger surging. This is because the turbocharger is
less efficient and the amount of scavenge air supplied to the turbocharger at a certain part load (when moving to the left
engine is low, and consequently also the cooling effect on in the power-rpm diagram). On the other hand, with a new
the combustion chamber. Often e.g. the exhaust valve tem- and clean hull in ballast draft the power absorption is
lighter and full power will not be absorbed as the maximum
perature can be higher at low load (when running accord-
engine speed limits the speed range upwards. These draw-
ing to the propeller law) than at full load. Furthermore, the
smallest distance to the so-called surge limit of the com- backs are avoided by specifying CP-propellers.
pressor typically occurs at part load. Some margin is re- A similar problem is encountered on twin-screw (or
quired to permit some reasonable wear and fouling of the multi-screw) ships with fixed-pitch propellers running
turbocharging system and different ambient conditions with only one propeller. If one propeller is wind-milling
(e.g. suction air temperature). (rotating freely), the other propeller will feel an increased
As a rule, the higher the specified mean effective pressure power absorption, and even more so, if the other propeller
the narrower is the permitted engine operating range. is blocked. The phenomenon is more pronounced on ships
There is a trend in the industry to specify higher and higher with a small block coefficient. The issue is illustrated in the
diagram below.
outputs, unfortunately on the expense of the width of the
operating field. This is the reason why separate operating
fields may be specified for different output stages, and the
available output for FP-propellers may be lower than for
CP-propellers. Today’s development towards lower emis-
Figure 2.1. Propeller power absorption in different
conditions - example

3
Single screw ships
Prope ller power absorption, relative

Bollard pull
Free running

2 Twin screw ships

Other propeller locked
Other propeller trailing (windmilling)

0
0 20 40 60 80 100
Propeller speed, relative

6 Marine Project Guide W20 - 1/2002

 2. Operating ranges

The figure also indicates the magnitude of the so-called 2.2. Matching the engines with
bollard pull curve, which means the propeller power ab-
sorption curve at zero ship speed. It is a relevant condition driven equipment
for some ship types, such as tugs, trawlers and icebreakers.
This diagram is valid for open propellers. Propellers run- 2.2.1. CP-propeller
ning in nozzles are less sensitive to the speed of advance of Controllable pitch propellers are normally dimensioned
the ship. and classified to match the Maximum Continuous Rating
The bollard pull curve is also relevant for all FPP applica- of the prime mover(s). In case two (or several) engines are
tions since the power absorption during acceleration is al- connected to the same propeller it is normally dimensioned
ways somewhere between the free running curve and the corresponding to the total power of all connected prime
bollard pull curve! If the free sailing curve is very close to movers. This is also the case if the propeller is driven by
the 100% engine power curve and the bollard pull curve at prime movers of different types, as e.g. one diesel engine
the same time is considerably higher than the 100% engine and one electric motor (which may work as a shaft genera-
power curve, then the acceleration from zero ship speed tor in some operating modes). In case the total power of all
will be very difficult. This is because the propeller will re- connected prime movers will never be utilised, classifica-
quire such a high torque at low speed that the engine is not tion societies can approve a dimensioning for a lower
capable of increasing the speed. As a consequence the pro- power in case the plant is equipped with an automatic over-
peller will not develop enough thrust to accelerate the ship. load protection system. The rated power of the propeller
Heavy overload will also occur on a twin-screw vessel with will affect the blade thickness, hub size and shafting dimen-
FP propellers during manoeuvring, when one propeller is sions.
reversed and the other one is operating forward. When Designing a CP-propeller is a complex issue, requiring
dimensioning FP propellers for a twin screw vessel, the compromises between efficiency, cavitation, pressure
power absorption with only one propeller in operation pulses, and limitations imposed by the engine and a possi-
should be max. 90% of the engine power curve, or alterna- ble shaft generator, all factors affecting the blade geometry.
tively the bollard pull curve should be max 120% of the en- Generally speaking the point of optimisation (an optimum
gine power curve. Otherwise the engine must be de-rated pitch distribution) should correspond to the service speed
20-30% from the normal output for FPP applications. This and service power of the ship, but the issue may be compli-
will involve extra costs for non-standard design and sepa- cated in case the ship is intended to sail with various ship
rate EIAPP certification. For this reason it is recom- speeds, and even with different operating modes. Shaft
mended to select CP-propellers for twin-screw ships with generators or generators (or any other equipment) con-
mechanical propulsion. nected to the free end of the engine should be considered
An FP-propeller should never be specified for a in case these will be used at sea.
twin-in/single-out gear as one engine is not capable of The propeller efficiency is typically highest when running
driving a propeller designed for the power of two engines. along the propeller curve defined by the design pitch, in
For ships intended for operation in heavy ice, the addi- other word requiring the engine at part load to run slowly
tional torque of the ice should furthermore be considered. and heavily. Typically also the efficiency of a diesel engine
running at part load is somewhat higher when running at a
For selecting the machinery, typically a sea margin of
lower speed than the nominal.
10…15 % is applied, sometimes even 25…30 %. This
means the relative increase in shaft power from trial condi- Pressure side cavitation may easily occur when running at
tions to typical service conditions (a margin covering in- high propeller speed and low pitch. This is a noisy type of
crease in ships resistance due to fouling of hull and cavitation and it may also be erosive. However the pressure
propeller, rough seas, wind, shallow water depth etc). Fur- side cavitation behaviour can be improved a lot by a suit-
thermore, an engine margin of 10…15 % is often applied, able propeller blade design. Also cavitation at high power
meaning that the ship’s specified service speed should be may cause increased pressure pulses, which can be reduced
achieved with 85…90 % of the MCR. These two inde- by increased skew angle and optimized blade geometry.
pendent parameters should be selected on a project spe- It is of outmost importance that the propeller designer has
cific basis. information about all the actual operation conditions for
The minimum speed of the engine is a project specific is- the vessel. Often the main objective is to minimise the ex-
sue, involving issues like torsional vibrations, elastic tent and fluctuation of the suction side cavitation to reduce
mounting, built-on pumps etc. propeller-induced hull vibrations and noise at high power,
while simultaneously avoiding noisy pressure side cavita-
In projects where the standard operating field, standard
tion and a large drop in efficiency at reduced propeller
output, or standard nominal speed do not satisfy all project
pitch and power.
specific demands, the engine maker should be contacted.

Marine Project Guide W20 - 1/2002 7

 2. Operating ranges

The propeller may enter the pressure side cavitation area To optimise the operating performance considering these
already when reducing the power to less than half, main- limitations CP-propellers are typically operating along a
taining nominal speed. In twin-in/single-out installations preset combinator curve, combining optimum speed and
the plant cannot be operated continuously with one engine pitch throughout the whole power range, controlled by
and a shaft generator connected, if the shaft generator re- one single control lever on the bridge. Applications with
quires operation at nominal propeller speed. two engines connected to the same propeller must have
Many solutions are possible to solve this problem: separate combinator curves for one engine operation and
twin engine operation. This applies similarly to twin-screw
• The shaft generator (connected to the secondary side of
vessels. Two or several combinator curves may be foreseen
the clutch) is used only when sailing with high power.
in complicated installations for different operating modes
• The shaft generator (connected to the secondary side of (one-engine, two-engines, manoeuvring, free running etc).
the clutch) is used only when manoeuvring with low or At a given propeller speed and pitch, the ship’s speed af-
moderate power, the transmission ratio being selected to fects the power absorption of the propeller. This effect is
give nominal frequency at reduced propeller speed. to some extent ship-type specific, being more pronounced
• The shaft generator is connected to the primary side of on ships with a small block coefficient. The power absorp-
the clutch of one of the engines, and can be used inde- tion of the propeller can sometimes be almost twice as high
pendently from the propeller, e.g. to produce power for during acceleration than during free steady-state running.
thrusters during manoeuvring. Navigation in ice can also add to the torque absorption of
• No shaft generator is installed. the propeller.
This type of issues are not only operational of nature, they An engine can deliver power also to other equipment like a
have to be considered at an early stage when selecting the pump, which can overload the engine if used without prior
machinery configuration. For all these reasons it is essential load reduction of the propeller.
to know the ship’s operating profile when designing the For the above mentioned reasons an automatic load con-
propeller and defining the operating modes. trol system is required in all installations running at variable
In normal applications no more than two engines should speed. The purpose of this system is to protect the engine
be connected to the same propeller. from thermal load and surging of the turbocharger. With
this system the propeller pitch is automatically reduced
CP-propellers typically have the option of being operated
when a pre-programmed load versus speed curve (the
at variable speed. To avoid the above mentioned pressure
“load curve”) is exceeded, overriding the combinator
side cavitation the propeller speed should be kept suffi-
curve if necessary. The load information must be derived
ciently below the cavitation limit, but not lower than neces-
from the actual fuel rack position and the speed should be
sary. On the other hand, there are also limitations on the
the actual speed (and not the demand). A so-called over-
engine’s side, such as avoiding thermal overload at lower
load protection, which is active only at full fuel pump set-
speeds.
tings, is not sufficient in variable speed applications.
The diagrams below show the operating ranges for
CP-propeller installations. The design range for the
combinator curve should be on the right hand side of the
nominal propeller curve. Operation in the shaded area is
permitted only temporarily during transients.

8 Marine Project Guide W20 - 1/2002

 2. Operating ranges

Operating field for CP Propeller The FP-propeller should normally be designed to absorb
Mechanical Fuel Stop MCR
100 maximum 85 % of the maximum continuous output of the
main engine (power transmission losses included) at nomi-
CSR
90 nal speed when the ship is on trial. Typically this corre-
(85%)
Max. Output Limit
80
sponds to 81 – 82 % for the propeller itself (excluding
Operation Temporarily
Allowed power transmission losses). This is typically referred to as
70 the “light running margin”, a compensation for expected
Nominal Propeller Curve
60
future drop in revolutions for a constant given power, typi-
Load (%)

cally 5-6 %.
50 Example of
Combinator Curve For ships intended for towing, the bollard pull condition
40
needs to be considered as explained earlier. The propeller
should be designed to absorb not more than 95 % of the
30 maximum continuous output of the main engine at nomi-
Min. Speed
20
nal speed when operating in towing or bollard pull condi-
Idling/Clutch-In
Speed Range tions, whichever service condition is relevant. In order to
10 reach 100 % MCR it is allowed to increase the engine speed
0
to 101.7 %. The speed does not need to be restricted to 100
30 40 50 60 70 80 90 100 110 % after bollard pull tests have been carried out. The ab-
Speed (%) sorbed power in free running and nominal speed is then
relatively low, e.g. 50 – 65 % of the output at service condi-
The clutch-in speed is a project specific issue. From the en- tions.
gine point of view, the clutch-in speed should be high Operating field for FP Propeller
enough to have a sufficient torque available, but not too MCR
Mechanical Fuel Stop
high. The slip time on the other hand should be as long as 100
possible. In practise longer slip times than 5 seconds are CSR
90
exceptions, but the clutch should typically be dimensioned Max. Output Limit
(85%)

so that it allows a slip time of at least 3 seconds. From the 80 Operation Temporarily
clutch point of view, a high clutch-in speed causes a high Allowed
thermal load on the clutch itself, which has to be taken into 70
Propeller Curves
account when specifying the clutch. A reasonable compro- 60
Load (%)

mise is to select the idle speed as clutch-in speed. In appli-

cations with two engines connected to the same propeller 50

(CP), it might be necessary to select a slightly higher 40

clutch-in speed. In case the engine has to continue driving
e.g. a pump or a generator (connected on the primary side 30
Min. Speed
of the clutch) during the clutch-in process a higher 20 Idling/Clutch-In
clutch-in speed may be necessary, but then also some Speed Range
speed drop has to be permitted. 10

CP-propellers in single-screw ships typically rotate coun- 0

ter-clockwise, requiring a clockwise sense of rotation of 30 40 50 60 70 80 90 100 110

the engine with a typically single-stage reduction gear. The Speed (%)

sense of rotation of propellers in twin-screw ships is a pro- The engine is non-reversible, so the gear box has to be of
ject specific issue. the reversible type. A shaft brake should also be installed.
A Robinson diagram (= four-quadrant diagram) showing
2.2.2. FP-propeller
the propeller torque ahead and astern for both senses of ro-
The fixed pitch propeller needs a very careful matching, as tation is needed to determine the parameters of the crash
explained above. The operational profile of the ship is very stop.
important (acceleration requirements, loading conditions, FP-propellers in single-screw ships typically rotate clock-
sea conditions, manoeuvring, fouling of hull and propeller wise, requiring a counter clockwise sense of rotation of the
etc). engine with a typically single-stage (in the ahead mode) re-
verse reduction gear.

Marine Project Guide W20 - 1/2002 9

 2. Operating ranges

2.2.3. Water jets ter jet power absorption should be dimensioned close to
100% MCR to get out as much power as possible. How-
Water jets also requires a careful matching with the engine,
ever, some margin should be left, due to tolerances in the
similar to that of the fixed pitched propeller. However, power estimates of the jet and the small, but still present,
there are some distinctive differences between the increase in torque demand due to a possible increase in
dimensioning of a water jet compared to that of a fixed ship resistance.
pitch propeller.
The torque demand at lower speeds should also be care-
Water jets operate at variable speed depending on the
fully compared to the operating field of the engine.
thrust demand. The power absorption vs. rpm of a water Engines with highly optimised turbo chargers can have an
jet follows a cubic curve under normal operation. The operating field that does not cover the water jet power de-
power absorption vs. rpm is higher when the ship speed is mand over the entire speed range. Also the lower efficiency
reduced, with the maximum torque demand occurring
of the transmission and the reduction gear at part load
when manoeuvring astern. The power absorption vs. revo-
should be accounted for in the estimation of the power ab-
lution speed for a typical water jet is illustrated in the dia-
sorption. The time spent at manoeuvring should be con-
gram below. sidered as well, if the power absorption in manoeuvring
Water jet power absorption mode exceeds the operating field for continuous operation
for the engine. In projects where the standard operating
Normal operation
field does not satisfy all project specific demands, the en-
Manoeuvring, ahead
Relative waterjet power absorption

Manoeuvring, astern gine maker should be contacted.

100
2.2.4. Other propulsors
90
80 Azimuth thrusters
70 Azimuth thrusters can be equipped with fixed-pitch or
60 controllable-pitch propellers. Most of the above given in-
50 structions for CP- and FP-propellers are valid also in case
of azimuth thrusters, however with some specific features.
40
The azimuth thrusters offer a good manoeuvrability by
30
turning the propulsor. During slow manoeuvring in har-
20 bour the propeller works close to the bollard pull curve,
10 which therefore has to be properly considered especially
0 when matching azimuth thrusters with FP-propeller with
0 10 20 30 40 50 60 70 80 90 100 the engine. Reversing and crash stop are also performed by
Relative impeller speed turning the FP-thrusters (rather than changing the sense of
rotation), causing a heavy propeller curve but in a different
The reversal of the thrust from the water jet is achieved by way than with an ordinary shaft line.
a reversing bucket. Moving the bucket into the jet stream
Tunnel thrusters
and thereby deflecting it forward, towards the bow, re-
verses the thrust from the jet. The bucket can be gradually Tunnel thrusters are typically driven by electric motors,
inserted in the water jet, so that only part of the jet is de- but can also be driven by diesel engines. Tunnel thrusters
flected. This way the thrust can be controlled continuously can be equipped with fixed-pitch or controllable-pitch
from full ahead to full astern just by adjusting the position propellers. Tunnel thrusters with CP-propellers can be op-
of the bucket. The reversing bucket is typically operated at erated at constant speed, which may be feasible to get the
part speed only. quickest possible response, or according to a combinator
The speed of the ship has only a small influence on the rev- curve. A load control system is required. A non-reversible
olution speed of water jet, unlike the case for a fixed diesel engine driving a tunnel thruster with FP-propeller is
pitched propeller. This means that there will only be a very typically not a feasible solution, as an extra reversible gear
small change in water jet speed when the ship speed drops. box would be needed.
Increased resistance, due to fouling of the hull, rough seas, Voith-Schneider propellers
wind or shallow water depth, will therefore not affect the
torque demand on an engine coupled to a water jet in the This type of propulsor is operated at variable speed and
same degree as on an engine coupled to a fixed pitched pro- pitch. It is important to have some kind of load control sys-
tem to prevent overload over the whole speed range, as de-
peller. This means that the water jet can be matched closer
scribed in previous chapters.
to the MCR than a fixed pitched propeller. In fact, the wa-

10 Marine Project Guide W20 - 1/2002

 2. Operating ranges

2.2.5. Dredgers 2.2.6. Generators

The power generation plant of a dredger can be of differ- Generators are typically operated at nominal speed. Mod-
ent configurations: ern generators are typically synchronous AC machines,
• Diesel-electric. Propulsors and dredging pumps are elec- producing a frequency equalling the number of pole pairs
trically driven. This is a good and flexible solution, but times the rotational speed. The synchronous speed of such
also the most expensive. generators is listed below.
• Mechanically driven main propellers, and electrically Table 2.1. Synchronous speed of generators
driven dredging pumps and thrusters. The main engines
and generators driven e.g. from the free end of the Number Synchr. speed, rpm
Number
crankshaft are running at constant speed, and the dredg- of pole
pairs of poles 50 Hz 60 Hz
ing pumps can be operated at variable speed with a fre-
quency converter. This is a good, flexible and 1 2 3000 3600
cost-effective solution. 2 4 1500 1800
The configuration with the main engine running at con-
3 6 1000 1200
stant speed has proved to be a good solution, also capable
of taking the typical load transients coming from the 4 8 750 900
dredging pumps.
5 10 600 720
• Mechanically driven main propellers and dredging
6 12 500 600
pumps. The main engines have to operate at variable
speed. This may appear to be the cheapest solution, but 7 14 428.6 514.3
it has operational limitations. 8 16 375 450
This configuration, when the dredging pumps are me-
9 18 333.3 400
chanically driven e.g. from the free end of the crankshaft,
some dredging modes may require a capability to run a 10 20 300 360
constant and full torque down to 70 or 80 % of the nominal 11 22 272.7 327.3
speed. This kind of torque requirement is difficult to meet
with a standard diesel engine and normally de-rating of the
main engines is required. The trend in the industry to spec- In some rare installations, shaft generators or die-
ify higher and higher outputs has also lead to narrower op- sel-generators may be operated at variable frequency,
erating fields, so this configuration is becoming less and sometimes referred to as floating frequency. This may be
less feasible. the case with a shaft generator supplying the ship’s service
electricity, when it may be clearly feasible to operate the
propulsion plant at variable speed for reasons of propeller
efficiency or cavitation.
Desired transmission ratios between main engines and
shaft generators cannot always be exactly found, as the
number of teeth in the gear box has to be selected in steps
of complete teeth. The result is illustrated in the example
below. In this example, the nominal frequency of the shaft
generator is obtained inside the speed range of the main en-
gine.

Marine Project Guide W20 - 1/2002 11

 2. Operating ranges

Table 2.2. Example of relative speeds between engine and PTO-generator.

Propeller PTO generator

Engine
speed
output speed speed frequency

% % % rpm % Hz

Engine MCR 100 100 100 1512 100.8 50.4

Nominal frequency of PTO generator 99.2 97.6 99.2 1500 100 50

95 % frequency of PTO generator 94.2 83.7 94.2 1425 95 47.5

85 % of engine MCR, propeller law 94.7 85 94.7 1432 95.5 47.7

85 % of engine MCR, constant speed 100 85 100 1512 100.8 50.4

This is also the case when the generator nominal speed is a The electrical system onboard the ship must be designed
multiple of the nominal speed of the engine. The number so that the diesel generators are protected from load steps
of teeth is selected to permit all teeth being in contact with that exceed the limit. Normally system specifications must
all teeth of the other gear wheel, to avoid uneven wear. To be sent to the classification society for approval and the
achieve this target, gear wheels with a multiple number of functionality of the system is to be demonstrated during
teeth compared with its smaller pair should be avoided. the ship’s trial.
This is valid for the main power transmission from the en- The loading performance is affected by the rotational iner-
gine to the propeller, as well as for PTOs for shaft genera- tia of the whole generating set, the speed governor adjust-
tors. In other words cases where a combination of tooth ment and behaviour, generator design, alternator
numbers giving exactly the desired transmission ratio can excitation system, voltage regulator behaviour and nomi-
be found, it is not feasible to use them. nal output.
The maximum output of diesel engines driving auxiliary Loading capacity and overload specifications are to be de-
generators and diesel engines driving generators for pro- veloped in co-operation between the plant designer, en-
pulsion is 110 % of the MCR. gine manufacturer and classification society at an early
stage of the project. Features to be incorporated in the
power management systems are presented in the Chapter
2.3. Loading capacity for electrical power generation.
The loading rate of a highly supercharged diesel engine
must be controlled, because the turbocharger needs time to 2.3.3. Auxiliary engines driving generators
accelerate before it can deliver the required amount of air. The load should always be applied gradually in normal op-
The load should always be applied gradually in normal op- eration. This will prolong the lifetime of engine compo-
eration. nents. The class rules only determine what the engine must
be capable of, if an emergency situation occurs. In an emer-
2.3.1. Diesel-mechanical propulsion gency situation the engine can be loaded in three equal
The loading is to be controlled by a load increase steps with minimum 5 seconds between each step. Pro-
programme, which is included in the propeller control sys- vided that the engine is preheated to a HT-water tempera-
tem. ture of 60…70ºC the engine can be loaded immediately
after start.
2.3.2. Diesel-electric propulsion The fastest loading is achieved with a successive gradual
increase in load from 0 to 100 %. It is recommended that
Class rules regarding load acceptance capability should not the switchboards and the power management system are
be interpreted as guidelines on how to apply load on the en- designed to increase the load as smoothly as possible.
gine in normal operation. The class rules only determine
The electrical system onboard the ship must be designed
what the engine must be capable of, if an emergency situa-
tion occurs. In an emergency situation the engine can be so that the diesel generators are protected from load steps
loaded in three equal steps in accordance with class require- that exceed the limit. Normally system specifications must
be sent to the classification society for approval and the
ment.
functionality of the system is to be demonstrated during
the ship’s trial.

12 Marine Project Guide W20 - 1/2002

 2. Operating ranges

2.4. Ambient conditions 2.4.3. High water temperature

The maximum inlet LT-water temperature is + 38ºC.
2.4.1. High air temperature Higher temperatures would cause an excessive thermal
The maximum inlet air temperature is + 45ºC. Higher tem- load on the engine, and can be permitted only if de-rating
peratures would cause an excessive thermal load on the en- the engine (permanently lowering the MCR) 0.3 % for each
gine, and can be permitted only by de-rating the engine 1ºC above + 38ºC.
(permanently lowering the MCR) 0.35 % for each 1ºC
above + 45ºC. 2.4.4. Operation at low load and idling
The engine can be started, stopped and operated on heavy
2.4.2. Low air temperature fuel under all operating conditions. Continuous operation
When designing ships for low temperatures the following on heavy fuel is preferred rather than changing over to die-
minimum inlet air temperature shall be taken into consid- sel fuel at low load operation and manoeuvring. The fol-
eration: lowing recommendations apply:

• For starting + 5ºC. Absolute idling (declutched main engine,

• For idling: - 5ºC. disconnected generator)
• At high load: - 10ºC. Maximum 5 minutes (recommended about 1 min for post
cooling), if the engine is to be stopped after the idling.
At high load, cold suction air with a high density causes
high firing pressures. The given limit is valid for a standard Operation at < 20 % load on HFO or < 10
engine. % on MDF
For temperatures below 0ºC special provisions may be Maximum 100 hours continuous operation. At intervals of
necessary on the engine or ventilation arrangement. 100 operating hours the engine must be loaded to mini-
Other guidelines for low suction air temperatures are given mum 70 % of the rated load.
in the chapter for Combustion air system.
Operation at > 20 % load on HFO or > 10
% on MDF
No restrictions.

Marine Project Guide W20 - 1/2002 13

 3. Technical data tables

3. Technical data tables

Diesel engine Wärtsilä 4L20 ME AE AE AE AE
Engine speed RPM 1000 720 750 900 1000
Engine output kW 720 520 540 680 720
Engine output HP 980 710 730 920 980
Cylinder bore mm 200
Stroke mm 280
Swept volume dm³ 35,2
Compression ratio 15
Compression pressure, max. bar 167 150 150 167 167
Firing pressure, max. bar 185 170 170 185 185
Charge air pressure at 100% load bar 0,3
Mean effective pressure bar 24,6 24,6 24,6 25,8 24,6
Mean piston speed m/s 9,3 6,7 7 8,4 9,3
Idling speed RPM 350
Combustion air system
Flow of air at 100% load kg/s 1,42 0,94 0,99 1,25 1,42
Ambient air temperature, max. °C 45
Air temperature after air cooler °C 45…60
Air temperature after air cooler, alarm °C 75
Exhaust gas system
Exhaust gas flow (100% load) 3) kg/s 1,46 0,97 1,02 1,39 1,46
Exhaust gas flow ( 85% load) 3) kg/s 1,25 0,84 0,89 1,21 1,28
Exhaust gas flow ( 75% load) 3) kg/s 1,1 0,76 0,81 1,08 1,15
Exhaust gas flow ( 25% load) 3) kg/s 0,73 0,55 0,59 0,77 0,84
Exhaust gas temp. after turbocharger (100% load) 1) 3) °C 350 360 360 340 350
Exhaust gas temp. after turbocharger ( 85% load) 1) 3) °C 365 360 360 340 350
Exhaust gas temp. after turbocharger ( 75% load) 1) 3) °C 370 360 365 340 350
Exhaust gas temp. after turbocharger ( 50% load) 1) 3) °C 390 370 370 350 360
Exhaust gas back pressure drop, max. kPa 3
Diameter of turbocharger connection mm 200
Exhaust gas pipe diameter, min. mm 300 250 250 300 300
Calculated dia for 35 m/s mm 305 251 257 295 305
Heat balance 2) 3)
Jacket water kW 161 127 132 149 161
Charge air kW 220 157 161 206 220
Lubricating oil kW 85 67 69 78 85
Exhaust gases kW 523 356 374 490 523
Radiation kW 42 31 31 37 42
Fuel system
Pressure before injection pumps kPa (bar) 600(6)
Pump capacity, MDF, engine driven m³/h 0,41 0,87 0,9 0,41 0,41
Fuel consumption (100% load) 3) g/kWh 195 194 194 193 195
Fuel consumption ( 85% load) 3) g/kWh 192 195 195 193 195
Fuel consumption ( 75% load) 3) g/kWh 193 197 197 194 196
Fuel consumption ( 50% load) 3) g/kWh 200 204 204 200 201
Leak fuel quantity, clean MDF fuel (100% load) kg/h 0,5 0,4 0,4 0,5 0,5
Lubricating oil system
Pressure before engine, nom. kPa (bar) 450 (4,5)
Pressure before engine, alarm kPa (bar) 300 (3)
Pressure before engine, stop kPa (bar) 200 (2)

14 Marine Project Guide W20 - 1/2002

 3. Technical data tables

Priming pressure, nom. kPa (bar) 80 (0,8)

Priming pressure, alarm kPa (bar) 50 (0,5)
Temperature before engine, nom. °C 63
Temperature before engine, alarm °C 80
Temperature after engine, abt. °C 78
Pump capacity (main), engine driven m³/h 28
Pump capacity (main), separate m³/h 18
Pump capacity (priming) 4) m³/h 6,9/8,4
Oil volume, wet sump, nom. m³ 0,27
Oil volume in separate system oil tank, nom. m³ 1 0,7 0,7 0,9 1
Filter fineness, nom. microns/60% 15 15 15 15 15
Filter difference pressure, alarm kPa (bar) 150 (1,5)
Oil consumption (100% load), abt. 5) g/kWh 0,6
Cooling water system
High temperature cooling water system
Pressure before engine, nom. kPa (bar) 200 (2,0) + static
Pressure before engine, alarm kPa (bar) 100 (1,0) + static
Pressure before engine, max. kPa (bar) 350 (3,5)
Temperature before engine, abt. °C 83
Temperature after engine, nom. °C 91
Temperature after engine, alarm °C 105
Temperature after engine, stop °C 110
Pump capacity, nom. m³/h 18,5 18 18,5 18,5 20
Pressure drop over engine kPa (bar) 50 (0,5)
Water volume in engine m³ 0,09
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Delivery head of stand-by pump kPa (bar) 200 (2)
Low temperature cooling water system
Pressure before charge air cooler, nom. kPa (bar) 200 (2) + static
Pressure before charge air cooler, alarm kPa (bar) 100 (1) + static
Pressure before charge air cooler, max. kPa (bar) 350 (3,5)
Temperature before charge air cooler, max. °C 38
Temperature before charge air cooler, min. °C 25
Pump capacity, nom. m³/h 20 19 20 20 24
Pressure drop over charge air cooler kPa (bar) 30 (0,3)
Pressure drop over oil cooler kPa (bar) 30 (0,3)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Delivery head of stand-by pump kPa (bar) 200 (2)
Starting air system
Air supply pressure before engine (max.) Mpa (bar) 3 (30)
Air supply pressure, alarm Mpa (bar) 1,8 (18)
Air consumption per start (20°C) 6) Nm³ 0,4
1) At an ambient temperature of 25°C.
2) The figures are at 100% load and include the 5% tolerance on sfoc and engine driven pumps.
3) According to ISO 3046/1, lower calorific value 42 700 kJ/kg, with engine driven pumps. Tolerance 5%.
Constant speed applications are Auxiliary and DE. Mechanical propulsion variable speed applications according to propeller law.
4) Capacities at 50 and 60 Hz respectively.
5) Tolerance + 0.3 g/kWh
6) At remote and automatic starting, the consumption is 1.2 Nm³
Subject to revision without notice.

Marine Project Guide W20 - 1/2002 15

 3. Technical data tables

Diesel engine Wärtsilä 5L20 ME AE AE

Engine speed RPM 1000 900 1000
Engine output kW 825 775 825
Engine output HP 1120 1050 1120
Cylinder bore mm 200
Stroke mm 280
Swept volume dm³ 44
Compression ratio 15
Compression pressure, max. bar 155
Firing pressure, max. bar 175
Charge air pressure at 100% load bar 0,3
Mean effective pressure bar 22,5 23,5 22,5
Mean piston speed m/s 9,3 8,4 9,3
Idling speed RPM 350
Combustion air system
Flow of air at 100% load kg/s 1,5 1,42 1,5
Ambient air temperature, max. °C 45
Air temperature after air cooler °C 45…60
Air temperature after air cooler, alarm °C 75
Exhaust gas system
Exhaust gas flow (100% load) 3) kg/s 1,55 1,55 1,55
Exhaust gas flow ( 85% load) 3) kg/s 1,33 1,37 1,37
Exhaust gas flow ( 75% load) 3) kg/s 1,19 1,25 1,25
Exhaust gas flow ( 25% load) 3) kg/s 0,82 0,94 0,94
Exhaust gas temp. after turbocharger (100% load) 1) 3) °C 360 360 360
Exhaust gas temp. after turbocharger ( 85% load) 1) 3) °C 365 350 350
Exhaust gas temp. after turbocharger ( 75% load) 1) 3) °C 385 360 360
Exhaust gas temp. after turbocharger ( 50% load) 1) 3) °C 395 360 360
Exhaust gas back pressure drop, max. kPa 3
Diameter of turbocharger connection mm 250
Exhaust gas pipe diameter, min. mm 350
Calculated dia for 35 m/s mm 317 317 317
Heat balance 2) 3)
Jacket water kW 189 173 189
Charge air kW 240 226 240
Lubricating oil kW 101 91 101
Exhaust gases kW 602 558 602
Radiation kW 49 43 49
Fuel system
Pressure before injection pumps kPa (bar) 600(6)
Pump capacity, MDF, engine driven m³/h 0,58 0,58 0,58
Fuel consumption (100% load) 3) g/kWh 195 195 195
Fuel consumption ( 85% load) 3) g/kWh 194
Fuel consumption ( 75% load) 3) g/kWh 195 196 196
Fuel consumption ( 50% load) 3) g/kWh 202 208 208
Leak fuel quantity, clean MDF fuel (100% load) kg/h 0,7 0,7 0,7
Lubricating oil system
Pressure before engine, nom. kPa (bar) 450 (4,5) 450 (4,5) 450 (4,5)
Pressure before engine, alarm kPa (bar) 300 (3) 300 (3) 300 (3)
Pressure before engine, stop kPa (bar) 200 (2) 200 (2) 200 (2)
Priming pressure, nom. kPa (bar) 80 (0,8) 80 (0,8) 80 (0,8)
Priming pressure, alarm kPa (bar) 50 (0,5) 50 (0,5) 50 (0,5)
Temperature before engine, nom. °C 63

16 Marine Project Guide W20 - 1/2002

 3. Technical data tables

Temperature before engine, alarm °C 80

Temperature after engine, abt. °C 78
Pump capacity (main), engine driven m³/h 28
Pump capacity (main), separate m³/h 19,5
Pump capacity (priming) 4) m³/h 6,9/8,4
Oil volume, wet sump, nom. m³ 0,32
Oil volume in separate system oil tank, nom. m³ 1,1 1 1,1
Filter fineness, nom. microns/60% 15 15 15
Filter difference pressure, alarm kPa (bar) 150 (1,5) 150 (1,5) 150 (1,5)
Oil consumption (100% load), abt. 5) g/kWh 0,6
Cooling water system
High temperature cooling water system
Pressure before engine, nom. kPa (bar) 200 (2,0) + static
Pressure before engine, alarm kPa (bar) 100 (1,0) + static
Pressure before engine, max. kPa (bar) 350 (3,5)
Temperature before engine, abt. °C 83
Temperature after engine, nom. °C 91
Temperature after engine, alarm °C 105
Temperature after engine, stop °C 110
Pump capacity, nom. m³/h 25 25 25
Pressure drop over engine kPa (bar) 50 (0,5)
Water volume in engine m³ 0,105 0,09 0,09
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Delivery head of stand-by pump kPa (bar) 200 (2)
Low temperature cooling water system
Pressure before charge air cooler, nom. kPa (bar) 200 (2) + static
Pressure before charge air cooler, alarm kPa (bar) 100 (1) + static
Pressure before charge air cooler, max. kPa (bar) 350 (3,5)
Temperature before charge air cooler, max. °C 38
Temperature before charge air cooler, min. °C 25
Pump capacity, nom. m³/h 30 30 30
Pressure drop over charge air cooler kPa (bar) 30 (0,3)
Pressure drop over oil cooler kPa (bar) 30 (0,3)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Delivery head of stand-by pump kPa (bar) 200 (2)
Starting air system
Air supply pressure before engine (max.) Mpa (bar) 3 (30)
Air supply pressure, alarm Mpa (bar) 1,8 (18)
Air consumption per start (20°C) 6) Nm³ 0,4

1) At an ambient temperature of 25°C.

2) The figures are at 100% load and include the 5% tolerance on sfoc and engine driven pumps.
3) According to ISO 3046/1, lower calorific value 42 700 kJ/kg, with engine driven pumps. Tolerance 5%.
Constant speed applications are Auxiliary and DE. Mechanical propulsion variable speed applications according to propeller law.
4) Capacities at 50 and 60 Hz respectively.
5) Tolerance + 0.3 g/kWh
6) At remote and automatic starting, the consumption is 1.2 Nm³
Subject to revision without notice.

Marine Project Guide W20 - 1/2002 17

 3. Technical data tables

Diesel engine Wärtsilä 6L20 ME AE AE AE AE

Engine speed RPM 1000 720 750 900 1000
Engine output kW 1080 780 810 1020 1080
Engine output HP 1470 1060 1100 1390 1470
Cylinder bore mm 200
Stroke mm 280
Swept volume dm³ 52,8
Compression ratio 15
Compression pressure, max. bar 167 150 150 167 167
Firing pressure, max. bar 185 170 170 185 185
Charge air pressure at 100% load bar 0,3
Mean effective pressure bar 24,6 24,6 24,6 25,8 24,6
Mean piston speed m/s 9,3 6,7 7 8,4 9,3
Idling speed RPM 350
Combustion air system
Flow of air at 100% load kg/s 2,2 1,36 1,43 2,1 2,2
Ambient air temperature, max. °C 45
Air temperature after air cooler °C 45…60
Air temperature after air cooler, alarm °C 75
Exhaust gas system
Exhaust gas flow (100% load) 3) kg/s 2,26 1,4 1,48 2,16 2,26
Exhaust gas flow ( 85% load) 3) kg/s 1,93 1,21 1,29 1,86 1,97
Exhaust gas flow ( 75% load) 3) kg/s 1,69 1,09 1,16 1,68 1,78
Exhaust gas flow ( 25% load) 3) kg/s 1,11 0,79 0,84 1,2 1,29
Exhaust gas temp. after turbocharger (100% load) 1) 3) °C 330 370 370 330 330
Exhaust gas temp. after turbocharger ( 85% load) 1) 3) °C 335 380 380 330 330
Exhaust gas temp. after turbocharger ( 75% load) 1) 3) °C 345 380 380 330 330
Exhaust gas temp. after turbocharger ( 50% load) 1) 3) °C 385 390 390 340 330
Exhaust gas back pressure drop, max. kPa 3
Diameter of turbocharger connection mm 250
Exhaust gas pipe diameter, min. mm 350 300 300 350 350
Calculated dia for 35 m/s mm 374 304 312 365 374
Heat balance 2) 3)
Jacket water kW 226 189 194 212 226
Charge air kW 327 201 223 305 327
Lubricating oil kW 143 106 108 133 143
Exhaust gases kW 727 530 549 685 727
Radiation kW 59 44 47 53 59
Fuel system
Pressure before injection pumps kPa (bar) 600(6)
Pump capacity, MDF, engine driven m³/h 1,49 0,87 0,9 1,34 1,49
Fuel consumption (100% load) 3) g/kWh 190 190 191 190 190
Fuel consumption ( 85% load) 3) g/kWh 188 191 192 189 190
Fuel consumption ( 75% load) 3) g/kWh 188 193 193 190 190
Fuel consumption ( 50% load) 3) g/kWh 195 203 203 197 197
Leak fuel quantity, clean MDF fuel (100% load) kg/h 0,9 0,6 0,7 0,7 0,9
Lubricating oil system
Pressure before engine, nom. kPa (bar) 450 (4,5)
Pressure before engine, alarm kPa (bar) 300 (3)
Pressure before engine, stop kPa (bar) 200 (2)
Priming pressure, nom. kPa (bar) 80 (0,8)
Priming pressure, alarm kPa (bar) 50 (0,5)
Temperature before engine, nom. °C 63

18 Marine Project Guide W20 - 1/2002

 3. Technical data tables

Temperature before engine, alarm °C 80

Temperature after engine, abt. °C 78
Pump capacity (main), engine driven m³/h 35 35 35 35 35
Pump capacity (main), separate m³/h 21
Pump capacity (priming) 4) m³/h 6,9/8,4
Oil volume, wet sump, nom. m³ 0,38
Oil volume in separate system oil tank, nom. m³ 1,5 1,1 1,1 1,4 1,5
Filter fineness, nom. microns/60% 25 25 25 25 25
Filter difference pressure, alarm kPa (bar) 150 (1,5)
Oil consumption (100% load), abt. 5) g/kWh 0,6
Cooling water system
High temperature cooling water system
Pressure before engine, nom. kPa (bar) 200 (2,0) + static
Pressure before engine, alarm kPa (bar) 100 (1,0) + static
Pressure before engine, max. kPa (bar) 350 (3,5)
Temperature before engine, abt. °C 83
Temperature after engine, nom. °C 91
Temperature after engine, alarm °C 105
Temperature after engine, stop °C 110
Pump capacity, nom. m³/h 30 27 28 29 30
Pressure drop over engine kPa (bar) 50 (0,5)
Water volume in engine m³ 0,12
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Delivery head of stand-by pump kPa (bar) 200 (2)
Low temperature cooling water system
Pressure before charge air cooler, nom. kPa (bar) 200 (2) + static
Pressure before charge air cooler, alarm kPa (bar) 100 (1) + static
Pressure before charge air cooler, max. kPa (bar) 28 350 (3,5)
Temperature before charge air cooler, max. °C 38
Temperature before charge air cooler, min. °C 25
Pump capacity, nom. m³/h 36 29 30 34 36
Pressure drop over charge air cooler kPa (bar) 30 (0,3)
Pressure drop over oil cooler kPa (bar) 30 (0,3)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Delivery head of stand-by pump kPa (bar) 200 (2)
Starting air system
Air supply pressure before engine (max.) Mpa (bar) 3 (30)
Air supply pressure, alarm Mpa (bar) 1,8 (18)
Air consumption per start (20°C) 6) Nm³ 0,4

1) At an ambient temperature of 25°C.

2) The figures are at 100% load and include the 5% tolerance on sfoc and engine driven pumps.
3) According to ISO 3046/1, lower calorific value 42 700 kJ/kg, with engine driven pumps. Tolerance 5%.
Constant speed applications are Auxiliary and DE. Mechanical propulsion variable speed applications according to propeller law.
4) Capacities at 50 and 60 Hz respectively.
5) Tolerance + 0.3 g/kWh
6) At remote and automatic starting, the consumption is 1.2 Nm³
Subject to revision without notice.

Marine Project Guide W20 - 1/2002 19

 3. Technical data tables

Diesel engine Wärtsilä 8L20 ME AE AE AE AE

Engine speed RPM 1000 720 750 900 1000
Engine output kW 1440 1040 1080 1360 1440
Engine output HP 1960 1410 1470 1850 1960
Cylinder bore mm 200
Stroke mm 280
Swept volume dm³ 70,4
Compression ratio 15
Compression pressure, max. bar 167 150 150 167 167
Firing pressure, max. bar 185 170 170 185 185
Charge air pressure at 100% load bar 0,3
Mean effective pressure bar 24,6 24,6 24,6 25,8 24,6
Mean piston speed m/s 9,3 6,7 7 8,4 9,3
Idling speed RPM 350
Combustion air system
Flow of air at 100% load kg/s 2,86 1,96 2,04 2,79 2,98
Ambient air temperature, max. °C 45
Air temperature after air cooler °C 45…60
Air temperature after air cooler, alarm °C 75
Exhaust gas system
Exhaust gas flow (100% load) 3) kg/s 2,94 2,02 2,1 2,87 3,06
Exhaust gas flow ( 85% load) 3) kg/s 2,5 1,74 1,81 2,48 2,67
Exhaust gas flow ( 75% load) 3) kg/s 2,18 1,57 1,62 2,24 2,41
Exhaust gas flow ( 25% load) 3) kg/s 1,44 1,11 1,15 1,61 1,76
Exhaust gas temp. after turbocharger (100% load) 1) 3) °C 350 360 360 350 340
Exhaust gas temp. after turbocharger ( 85% load) 1) 3) °C 355 360 360 340 340
Exhaust gas temp. after turbocharger ( 75% load) 1) 3) °C 360 360 360 340 340
Exhaust gas temp. after turbocharger ( 50% load) 1) 3) °C 390 370 370 350 350
Exhaust gas back pressure drop, max. kPa 3
Diameter of turbocharger connection mm 300
Exhaust gas pipe diameter, min. mm 400 350 350 400 400
Calculated dia for 35 m/s mm 433 362 369 428 438
Heat balance 2) 3)
Jacket water kW 330 244 254 307 330
Charge air kW 442 306 322 407 442
Lubricating oil kW 219 162 167 204 219
Exhaust gases kW 1057 684 708 890 943
Radiation kW 82 55 57 74 76
Fuel system
Pressure before injection pumps kPa (bar) 600(6)
Pump capacity, MDF, engine driven m³/h 1,92 1,48 1,54 1,73 1,92
Fuel consumption (100% load) 3) g/kWh 199 192 192 191 192
Fuel consumption ( 85% load) 3) g/kWh 198 193 193 190 191
Fuel consumption ( 75% load) 3) g/kWh 198 194 194 190 192
Fuel consumption ( 50% load) 3) g/kWh 203 202 202 199 199
Leak fuel quantity, clean MDF fuel (100% load) kg/h 1,2 0,8 0,9 1,1 1,2
Lubricating oil system
Pressure before engine, nom. kPa (bar) 450 (4,5)
Pressure before engine, alarm kPa (bar) 300 (3)
Pressure before engine, stop kPa (bar) 200 (2)
Priming pressure, nom. kPa (bar) 80 (0,8)
Priming pressure, alarm kPa (bar) 50 (0,5)
Temperature before engine, nom. °C 63

20 Marine Project Guide W20 - 1/2002

 3. Technical data tables

Temperature before engine, alarm °C 80

Temperature after engine, abt. °C 78
Pump capacity (main), engine driven m³/h 50 50 50 50 50
Pump capacity (main), separate m³/h 27
Pump capacity (priming) 4) m³/h 6,9/8,4
Oil volume, wet sump, nom. m³ 0,49
Oil volume in separate system oil tank, nom. m³ 1,9 1,4 1,5 1,8 1,9
Filter fineness, nom. microns/60% 25 25 25 25 25
Filter difference pressure, alarm kPa (bar) 150 (1,5)
Oil consumption (100% load), abt. 5) g/kWh 0,6
Cooling water system
High temperature cooling water system
Pressure before engine, nom. kPa (bar) 200 (2,0) + static
Pressure before engine, alarm kPa (bar) 100 (1,0) + static
Pressure before engine, max. kPa (bar) 350 (3,5)
Temperature before engine, abt. °C 83
Temperature after engine, nom. °C 91
Temperature after engine, alarm °C 105
Temperature after engine, stop °C 110
Pump capacity, nom. m³/h 40 35 37 39 40
Pressure drop over engine kPa (bar) 50 (0,5)
Water volume in engine m³ 0,15
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Delivery head of stand-by pump kPa (bar) 200 (2)
Low temperature cooling water system
Pressure before charge air cooler, nom. kPa (bar) 200 (2) + static
Pressure before charge air cooler, alarm kPa (bar) 100 (1) + static
Pressure before charge air cooler, max. kPa (bar) 350 (3,5)
Temperature before charge air cooler, max. °C 38
Temperature before charge air cooler, min. °C 25
Pump capacity, nom. m³/h 48 38 40 45 48
Pressure drop over charge air cooler kPa (bar) 30 (0,3)
Pressure drop over oil cooler kPa (bar) 30 (0,3)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Delivery head of stand-by pump kPa (bar) 200 (2)
Starting air system
Air supply pressure before engine (max.) Mpa (bar) 3 (30)
Air supply pressure, alarm Mpa (bar) 1,8 (18)
Air consumption per start (20°C) 6) Nm³ 0,4

1) At an ambient temperature of 25°C.

2) The figures are at 100% load and include the 5% tolerance on sfoc and engine driven pumps.
3) According to ISO 3046/1, lower calorific value 42 700 kJ/kg, with engine driven pumps. Tolerance 5%.
Constant speed applications are Auxiliary and DE. Mechanical propulsion variable speed applications according to propeller law.
4) Capacities at 50 and 60 Hz respectively.
5) Tolerance + 0.3 g/kWh
6) At remote and automatic starting, the consumption is 1.2 Nm³
Subject to revision without notice.

Marine Project Guide W20 - 1/2002 21

 3. Technical data tables

Diesel engine Wärtsilä 9L20 ME AE AE AE AE

Engine speed RPM 1000 720 750 900 1000
Engine output kW 1620 1170 1215 1530 1620
Engine output HP 2200 1590 1650 2080 2200
Cylinder bore mm 200
Stroke mm 280
Swept volume dm³ 79,2
Compression ratio 15
Compression pressure, max. bar 167 150 150 167 167
Firing pressure, max. bar 185 170 170 185 185
Charge air pressure at 100% load bar 0,3
Mean effective pressure bar 24,6 24,6 24,6 25,8 24,6
Mean piston speed m/s 9,3 6,7 7 8,4 9,3
Idling speed RPM 350
Combustion air system
Flow of air at 100% load kg/s 3,43 1,98 2,11 3,09 3,43
Ambient air temperature, max. °C 45
Air temperature after air cooler °C 45…60
Air temperature after air cooler, alarm °C 75
Exhaust gas system
Exhaust gas flow (100% load) 3) kg/s 3,52 2,05 2,18 3,17 3,52
Exhaust gas flow ( 85% load) 3) kg/s 3,05 1,79 1,91 2,76 3,08
Exhaust gas flow ( 75% load) 3) kg/s 2,67 1,62 1,73 2,47 2,79
Exhaust gas flow ( 25% load) 3) kg/s 1,74 1,18 1,27 1,76 2,05
Exhaust gas temp. after turbocharger (100% load) 1) 3) °C 340 360 360 340 340
Exhaust gas temp. after turbocharger ( 85% load) 1) 3) °C 350 360 360 340 340
Exhaust gas temp. after turbocharger ( 75% load) 1) 3) °C 350 370 370 340 340
Exhaust gas temp. after turbocharger ( 50% load) 1) 3) °C 370 380 380 350 330
Exhaust gas back pressure drop, max. kPa 3
Diameter of turbocharger connection mm 300
Exhaust gas pipe diameter, min. mm 450 350 350 450 450
Calculated dia for 35 m/s mm 470 365 376 446 470
Heat balance 2) 3)
Jacket water kW 380 280 291 353 380
Charge air kW 495 342 355 458 495
Lubricating oil kW 244 177 183 229 244
Exhaust gases kW 1044 771 800 985 1044
Radiation kW 79 63 66 75 79
Fuel system
Pressure before injection pumps kPa (bar) 600(6)
Pump capacity, MDF, engine driven m³/h 1,92 1,48 1,54 1,73 1,92
Fuel consumption (100% load) 3) g/kWh 191 192 192 190 191
Fuel consumption ( 85% load) 3) g/kWh 189 192 192 190 190
Fuel consumption ( 75% load) 3) g/kWh 190 193 193 190 191
Fuel consumption ( 50% load) 3) g/kWh 195 202 202 198 199
Leak fuel quantity, clean MDF fuel (100% load) kg/h 1,3 0,9 1 1,2 1,3
Lubricating oil system
Pressure before engine, nom. kPa (bar) 450 (4,5)
Pressure before engine, alarm kPa (bar) 300 (3)
Pressure before engine, stop kPa (bar) 200 (2)
Priming pressure, nom. kPa (bar) 80 (0,8)
Priming pressure, alarm kPa (bar) 50 (0,5)
Temperature before engine, nom. °C 63

22 Marine Project Guide W20 - 1/2002

 3. Technical data tables

Temperature before engine, alarm °C 80

Temperature after engine, abt. °C 78
Pump capacity (main), engine driven m³/h 50 50 50 50 50
Pump capacity (main), separate m³/h 30
Pump capacity (priming) 4) m³/h 6,9/8,4
Oil volume, wet sump, nom. m³ 0,55
Oil volume in separate system oil tank, nom. m³ 2,2 1,6 1,6 2,1 2,2
Filter fineness, nom. microns/60% 25 25 25 25 25
Filter difference pressure, alarm kPa (bar) 150 (1,5)
Oil consumption (100% load), abt. 5) g/kWh 0,6
Cooling water system
High temperature cooling water system
Pressure before engine, nom. kPa (bar) 200 (2,0) + static
Pressure before engine, alarm kPa (bar) 100 (1,0) + static
Pressure before engine, max. kPa (bar) 350 (3,5)
Temperature before engine, abt. °C 83
Temperature after engine, nom. °C 91
Temperature after engine, alarm °C 105
Temperature after engine, stop °C 110
Pump capacity, nom. m³/h 45 40 42 44 45
Pressure drop over engine kPa (bar) 50 (0,5)
Water volume in engine m³ 0,16
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Delivery head of stand-by pump kPa (bar) 200 (2)
Low temperature cooling water system
Pressure before charge air cooler, nom. kPa (bar) 200 (2) + static
Pressure before charge air cooler, alarm kPa (bar) 100 (1) + static
Pressure before charge air cooler, max. kPa (bar) 350 (3,5)
Temperature before charge air cooler, max. °C 38
Temperature before charge air cooler, min. °C 25
Pump capacity, nom. m³/h 54 43 45 50 54
Pressure drop over charge air cooler kPa (bar) 30 (0,3)
Pressure drop over oil cooler kPa (bar) 30 (0,3)
Pressure drop over central cooler, max. kPa (bar) 60 (0,6)
Pressure from expansion tank kPa (bar) 70…150 (0,7…1,5)
Delivery head of stand-by pump kPa (bar) 200 (2)
Starting air system
Air supply pressure before engine (max.) Mpa (bar) 3 (30)
Air supply pressure, alarm Mpa (bar) 1,8 (18)
Air consumption per start (20°C) 6) Nm³ 0,4

1) At an ambient temperature of 25°C.

2) The figures are at 100% load and include the 5% tolerance on sfoc and engine driven pumps.
3) According to ISO 3046/1, lower calorific value 42 700 kJ/kg, with engine driven pumps. Tolerance 5%.
Constant speed applications are Auxiliary and DE. Mechanical propulsion variable speed applications according to propeller law.
4) Capacities at 50 and 60 Hz respectively.
5) Tolerance + 0.3 g/kWh
6) At remote and automatic starting, the consumption is 1.2 Nm³
Subject to revision without notice.

Marine Project Guide W20 - 1/2002 23

 4. Description of the engine

4. Description of the engine

4.1. Definitions 4.2.5. Cylinder liner
In-line engine (1V93C0029) The cylinder liners are centrifugally cast of a special grey
cast iron alloy developed for good wear resistance and high
strength. They are of wet type, sealed against the engine
block metallically at the upper part and by O-rings at the
lower part. To eliminate the risk of bore polishing the liner
is equipped with an anti-polishing ring.

4.2.6. Piston
The piston is of composite design with nodular cast iron
skirt and steel crown. The piston skirt is pressure lubri-
cated, which ensures a well-controlled oil flow to the cylin-
der liner during all operating conditions. Oil is fed through
the connecting rod to the cooling spaces of the piston. The
piston cooling operates according to the cocktail shaker
principle. The piston ring grooves in the piston top are
hardened for better wear resistance.

4.2.7. Piston rings

The piston ring set consists of two directional compres-
sion rings and one spring-loaded conformable oil scraper
4.2. Main components ring. All rings are chromium-plated and located in the pis-
ton crown.
The dimensions and weights of engine parts are shown in
the chapter for dimensions and weights. 4.2.8. Cylinder head
4.2.1. Engine block The cylinder head is made of grey cast iron. The thermally
loaded flame plate is cooled efficiently by cooling water led
The main bearing caps, made of nodular cast iron, are fixed from the periphery radially towards the centre of the head.
from below by two hydraulically tensioned screws. They The bridges between the valves cooling channels are
are guided sideways by the engine block at the top as well as drilled to provide the best possible heat transfer.
at the bottom. Hydraulically tightened horizontal side
The mechanical load is absorbed by a strong intermediate
screws at the lower guiding provide a very rigid crankshaft
bearing. deck, which together with the upper deck and the side walls
form a box section in the four corners of which the hydrau-
lically tightened cylinder head bolts are situated. The ex-
4.2.2. Crankshaft haust valve seats are directly water-cooled.
The crankshaft is forged in one piece and mounted on the All valves are equipped with valve rotators.
engine block in an under-slung way. The crankshaft satis-
fies the requirements of all classification societies. 4.2.9. Camshaft and valve mechanism

4.2.3. Connecting rod The camshaft is built of one piece for each cylinder cam
piece with separate bearing pieces in between. The cam and
The connecting rod is of forged alloy steel. All connecting bearing pieces are held together with two hydraulically
rod studs are hydraulically tightened. Oil is led to the tightened centre screws. The drop forged completely hard-
gudgeon pin bearing and piston through a bore in the con- ened camshaft pieces have fixed cams. The camshaft bear-
necting rod. ing housings are integrated in the engine block casting and
are thus completely closed. The bearings are installed and
4.2.4. Main bearings and big end bearings removed by means of a hydraulic tool. The original installa-
tion in the factory in done with cooling of the bearing. The
The main bearings and the big end bearings are of the Al
based bi-metal type with steel back.

24 Marine Project Guide W20 - 1/2002

 4. Description of the engine

camshaft covers, one for each cylinder, seal against the en- The injection pumps have built-in roller tappets and are
gine block with a closed O-ring profile. through-flown to enable heavy fuel operation. They are
The valve tappets are of piston type with self-adjustment also equipped with a stop cylinder, which is connected to
of roller against cam to give an even distribution of the the electro-pneumatic overspeed protection system.
contact pressure. The valve springs make the valve mecha- The injection valve is centrally located in the cylinder head
nism dynamically stable. and the fuel is admitted sideways through a high pressure
connection screwed in the nozzle holder. The injection
4.2.10. Camshaft drive pipe between the injection pump and the high pressure
connection is well protected inside the hot box. The high
The camshafts are driven by the crankshaft through a gear pressure side of the injection system is thus completely sep-
train. arated from the exhaust gas side and the engine lubricating
oil spaces.
4.2.11. Turbocharging and charge air
cooling 4.2.13. Exhaust pipes
The selected turbocharger offers the ideal combination of The exhaust manifold pipes are made of special heat resis-
high-pressure ratios and good efficiency at full and part tant nodular cast iron alloy.
load. The charge air cooler is single stage type and cooled
The complete exhaust gas system is enclosed in an insulat-
by LT-water.
ing box consisting of easily removable panels. Mineral
wool is used as insulating material.
4.2.12. Injection equipment
The injection pumps are one-cylinder pumps located in
the “multi-housing”, which has the following functions:
• housing for the injection pump element
• fuel supply channel along the whole engine
• fuel return channel from each injection pump
• lubricating oil supply to the valve mechanism
• guiding for the valve tappets

Marine Project Guide W20 - 1/2002 25

 4. Description of the engine

4.3. Cross sections of the engine

40 30

26 Marine Project Guide W20 - 1/2002

 4. Description of the engine

4.4. Overhaul intervals and In this list HFO is based on HFO2 specification stated in
the chapter for general data and outputs.
expected life times
The following overhaul intervals and lifetimes are for guid-
ance only. Actual figures will be different depending on
service conditions. Expected component lifetimes have
been adjusted to match overhaul intervals.

Table 4.1. Time between overhauls and expected component lifetimes

HFO MDO HFO MDO

Time between Time between Expected comp. Expected comp.
overhauls (h) overhauls (h) lifetimes (h) lifetimes (h)
Main bearing 12000 16000 36000 48000
Big end bearing 12000 16000 24000 32000
Gudgeon pin bearing 12000 16000 48000 48000
Camshaft bearing bush 16000 16000 32000 32000
Camshaft intermed. gear bearing 16000 16000 32000 32000
Balancing shaft bearing, 4L20 12000 16000 24000 32000
Cylinder head 12000 16000
Inlet valve 12000 16000 36000 32000
Inlet valve seat 12000 16000 36000 32000
Exhaust valve 12000 16000 24000 32000
Exhaust valve seat 12000 16000 36000 32000
Valve guide, EX 12000 16000 24000 32000
Valve guide, IN 12000 16000 36000 48000
Piston crown 12000 16000 24000 48000
Piston rings 12000 16000 12000 16000
Cylinder liner 12000 16000 48000 64000
Antipolishing ring 12000 16000 24000 32000
Connecting rod 12000 16000
Connecting rod screws 12000 16000 24000 32000
Valve tappet and roller 24000 32000
Injection pump tappet and roller 24000 32000
Injection element 12000 16000 24000 32000
Injection valve 6000 8000
Injection nozzle 6000 8000 6000 8000
Water pump shaft seal 12000 12000 12000 12000
Water pump bearing 24000 24000
Turbocharger 24000 24000
Governor 12000 12000
Vibration damper Acc. to manuf. Acc. to manuf.

Marine Project Guide W20 - 1/2002 27

 5. Piping design, treatment and installation

5. Piping design, treatment and installation

5.1. General • in the tank top sections ( blocks) larger pipes shall be in-
stalled prior to smaller and if/when the deck sections are
This chapter provides general guidelines for the design,
upside down the large pipes comes closer to the under-
construction and installation of piping systems, however,
side of the deck.
not excluding other solutions of at least equal standard.
• the main lines shall be installed before the branches
Fuel, lubricating oil, fresh water and compressed air piping
is usually made in seamless carbon steel (DIN 2448) and • technically more difficult systems to be built before sim-
seamless precision tubes in carbon or stainless steel (DIN pler systems
2391), exhaust gas piping in welded pipes of corten or car- • the plan shall include the time schedule and manpower
bon steel (DIN 2458). Sea-water piping should be in needed
Cunifer or hot dip galvanized steel. Plastic pipes for part of
• Pockets shall be avoided and when not possible
the seawater piping require a special approval process.
equipped with drain plugs and air vents
Attention shall be given to the fire risk aspects. The fuel
• Leak fuel drain pipes shall have continuous slope
supply and return lines shall be designed so that they can be
fitted without tension. When flexible hoses are used, they • Vent pipes shall be continuously rising
shall be double hoses of approved type. If flexible hoses are • Flanged connections shall be used, cutting ring joints for
used in the compressed air system an outlet valve shall be precision tubes
fitted in front of the hose(s). Maintenance access and dismounting space of valves,
As it is already in the design phase necessary to know in ad- coolers and other devices shall be taken into consideration.
dition to how the system is supposed to work also how the Flange connections and other joints shall be located so that
system most feasibly can be built a fitting order plan shall dismounting of the apparatuses can be made with reason-
be done prior to construction. The following aspects but able effort. The estimated need of service during the ship’s
not necessarily limited to these shall be taken into consider- lifetime shall be taken into consideration when deciding
ation: the “open-inspect” priority order. This determines the ac-
cepted amount of dismantling and refitting work.

28 Marine Project Guide W20 - 1/2002

 5. Piping design, treatment and installation

5.2. Pipe dimensions

Table 5.1. Recommended maximum fluid velocities and flow rates for pipework*
Nominal pipe Flow rate [m/sec]
diameter Flow amount [m³/h]
(Media —> Sea-water Fresh water Lubricating oil Marine diesel oil Heavy fuel oil
Pipe material —> Steel galvanized Mild steel Mild steel Mild steel Mild steel
Pump side —>) suction delivery suction delivery suction delivery suction delivery suction delivery
1 1.4 1.5 1.5 0.6 1 0.9 1.1 0.5 0.6
32
2.9 4.1 4.3 4.3 1.7 2.9 2.6 3.2 1.4 1.7
1.2 1.6 1.7 1.7 0.7 1.2 1 1.2 0.5 0.7
40
5.4 7.2 7.7 7.7 3.2 5.4 4.5 5.4 2.3 3.2
1.3 1.8 1.9 1.9 0.8 1.4 1.1 1.3 0.5 0.8
50
9.2 12.7 13.4 13.4 5.7 9.9 7.8 9.2 3.5 5.7
1.5 2 2.1 2.1 0.8 1.5 1.2 1.4 0.6 0.9
65
17.9 23.9 25.1 25.1 9.6 17.9 14.3 16.7 7.2 10.8

80 1.6 2.1 2.2 2.2 0.9 1.6 1.3 1.5 0.6 1

29 38 39.8 39.8 16.3 29 23.5 27.1 10.9 18.1
1.8 2.2 2.3 2.3 0.9 1.6 1.4 1.6 0.7 1.2
100
50.9 62.2 65 65 25.5 45.2 39.6 45.2 19.8 33.9
2 2.3 2.4 2.4 1.1 1.7 1.5 1.7 0.8 1.4
125
88.4 101.6 106 110.4 48.6 75.1 66.3 75.1 35.3 61.9
2.2 2.4 2.5 2.6 1.3 1.8 1.5 1.8 0.9 1.6
150
140 152.7 159 165.4 82.7 114.5 95.4 114.5 57.3 108.2
2.3 2.5 2.6 2.7 1.3 1.8 — — — —
200
260.2 282.8 294.1 305.4 147 203.6 — — — —
2.6
Aluminium brass 294
2.5 2.6 2.7 2.7 1.3 1.9 — — — —
250
441.8 459.5 477.2 477.2 229.8 335.8 — — — —
2.7
Aluminium brass 447.2
2.6 2.6 2.7 2.7 1.3 1.9 — — — —
300
661.7 661.7 687.2 687.2 330.9 483.6 — — — —
2.8
Aluminium brass
712.5
2.6 2.6 2.7 2.7 1.4 2 — — — —
350
900.5 900.5 935.2 935.2 484.9 692.7 — — — —
2.8
Aluminium brass
969.8
2.6 2.7 2.7 2.7 1.4 2 — — — —
400
1176.2 1221.5 1221.5 1221.5 633.3 904.8 — — — —
2.8
Aluminium brass
1266.7
2.6 2.7 2.7 2.7 1.4 2 — — — —
450
1488.6 1545.9 1545.9 1545.9 801.6 1145.1 — — — —

Aluminium brass 2.9

1660.4
2.6 2.7 2.7 2.7 1.5 2.1 — — — —
500
1837.8 1908.5 1908.5 1908.5 1060.4 1484.6 — — — —
2.9
Aluminium brass
2049.9

* The velocities given in the above table are guidance figures only. National standards can also be applied.

Marine Project Guide W20 - 1/2002 29

 5. Piping design, treatment and installation

5.3. Trace heating • A design pressure of not less than 12 bar has to be se -
lected.
The following pipes shall be equipped with trace heating • The nearest pipe class to be selected is PN16.
(steam, thermal oil or electrical). It shall be possible to shut
off the trace heating. • Piping test pressure is normally 1.5 x the design pressure
= 18 bar.
• All heavy fuel pipes
Example 2:
• All leak fuel and filter flushing pipes carrying heavy fuel
The pressure on the suction side of the cooling water
pump is 1.0 bar. The delivery head of the pump is 3.0 bar,
5.4. Pressure class leading to a discharge pressure of 4.0 bar. The highest point
of the pump curve (at or near zero flow) is 1.0 bar higher
The pressure class of the piping should be higher than or than the nominal point, and consequently the discharge
equal to the design pressure, which should be higher than pressure may rise to 5.0 bar (with closed or throttled
or equal to the highest operating (working) pressure. The valves).
highest operating (working) pressure is equal to the setting
of the safety valve in a system. The pressure in the system • Consequently a design pressure of not less than 5.0 bar
shall be selected.
can
• originate from a positive displacement pump • The nearest pipe class to be selected is PN6.

• be a combination of the static pressure and the pressure • Piping test pressure is normally 1.5 x the design pressure
on the highest point of the pump curve for a centrifugal = 7.5 bar.
pump Standard pressure classes are PN4, PN6, PN10, PN16,
PN25, PN40, etc.
• rise in an isolated system if the liquid is heated e.g. pre-
heating of a system
Within this Project Guide there are tables attached to 5.5. Pipe class
drawings, which specify pressure classes of connections.
The pressure class of a connection can be higher than the The principle of categorisation of piping systems in classes
(e.g. DNV) or groups (e.g. ABS) by the classification soci-
pressure class required for the pipe.
eties can be used for choosing of:
Example 1:
• type of joint to be used
The fuel pressure before the engine should be 7 bar. The
safety filter in dirty condition may cause a pressure loss of • heat treatment
1.0 bar. The viscosimeter, automatic filter, preheater and • welding procedure,
piping may cause a pressure loss of 2.5 bar. Consequently • test method
the discharge pressure of the circulating pumps may rise to
Systems with high design pressures and temperatures and
10.5 bar, and the safety valve of the pump shall thus be ad-
hazardous media belong to class I (or group I), others to II
justed e.g. to 12 bar.
or III as applicable. Quality requirements are highest on
class I.
Examples of classes of piping systems as per DNV rules
are presented in the table below.

Table 5.2. Classes of piping systems as per DNV rules

Media Class I Class II Class III

bar °C bar °C bar °C
Steam > 16 or > 300 < 16 and < 300 <7 and < 170
Fuel oil > 16 or > 150 < 16 and < 150 <7 and < 60
Other media > 40 or > 300 < 40 and < 300 < 16 and < 200

30 Marine Project Guide W20 - 1/2002

 5. Piping design, treatment and installation

5.6. Insulation 5.8.1. Pickling

Pipes are pickled in an acid solution of 10% hydrochloric
In addition to the operational aspects of the different pip-
ing systems requiring insulation the fire risk aspect shall be acid and 10% formaline inhibitor for 4-5 hours, rinsed with
given attention (e.g. Insulating and/or shielding of hot sur- hot water and blown dry with compressed air.
faces). The following pipes shall be insulated After the acid treatment the pipes are treated with a neu-
tralizing solution of 10% caustic soda and 50 grams of
• All trace heated pipes
trisodiumphosphate per litre of water for 20 minutes at
• Exhaust gas pipes 40...50°C, rinsed with hot water and blown dry with com-
Insulation is also recommended for: pressed air.
• Pipes between engine or system oil tank and lubricating
oil separator 5.8.2. Flushing
• Pipes between engine and jacket water preheater More detailed recommendations on flushing procedures
• For personnel protection work safety any exposed parts are when necessary described under the relevant chapters
of pipes at walkways, etc., to be insulated to avoid exces- concerning the fuel oil system and the lubricating oil sys-
sive temperatures and risks for personnel injury. tem. Provisions are to be made to ensure that necessary
temporary bypasses can be arranged and that flushing
hoses, filters and pumps will be available when required.
5.7. Local gauges
Local thermometers should be installed wherever a new 5.9. Flexible pipe connections
temperature occurs, i.e. before and after heat exchangers,
etc. Great care must be taken to ensure the proper installation
of flexible pipe connections between resiliently mounted
Pressure gauges should be installed on the suction and dis-
engines and ship’s piping.
charge side of each pump.
• Flexible pipe connections must not be twisted
• Installation length of flexible pipe connections must be
5.8. Cleaning procedures correct
Instructions shall be given to manufacturers and/or fitters • Minimum bending radius must respected
of how different piping systems shall be treated, cleaned • Piping must be concentrically aligned
and protected before and during transportation and before
block assembly or assembly in the hull. All piping should • When specified the flow direction must be observed
be checked to be clean from debris before installation and • Mating flanges shall be clean from rust, burrs and
joining. All piping should be cleaned according to the pro- anticorrosion coatings
cedures listed below. • Bolts are to be tightened crosswise in several stages
Table 5.3. Pipe cleaning • Flexible elements must not be painted
• Rubber bellows must be kept clean from oil and fuel
System Methods
Fuel oil A, B, C, D, F • The piping must be rigidly supported close to the flexible
piping connections.
Lubricating oil A, B, C, D, F
Starting air A, B, C
Cooling water A, B, C
Exhaust gas A, B, C
Charge air A, B, C

A Washing with alkaline solution in hot water at 80°C for

degreasing (only if pipes have been greased)
B Removal of rust and scale with steel brush (not required
for seamless precision tubes)
C Purging with compressed air
D Pickling
F Flushing

Marine Project Guide W20 - 1/2002 31

 5. Piping design, treatment and installation

Flexible hoses (4V60B0100)

Bending radius

Radially not aligned

Too short inst. length

Stretched

Twisted

Correctly installed

32 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

6. Fuel oil system

6.1. General • Main and auxiliary engines are recommended to be con-
nected to separate fuel feed circuits.
Fuel characteristics of the fuels are presented under head-
ing Fuel characteristics in the Chapter for General data and
6.1.4. Local gauges
outputs.
This refers to HFO usage unless otherwise indicated. Local thermometers should be installed wherever a new
temperature occurs, i.e. before and after each heat
6.1.1. Operating principals exchanger etc.
Pressure gauges should be installed on the suction and dis-
The engine needs regulated fuel system before and after charge side of each pump.
the engine to control viscosity and temperature of the fuel.
Fuel systems are recommended to be closed due to better
control of viscosity and temperature and conservation of 6.2. MDF installations
the heating energy.
Fuel heating and cooling 6.2.1. General
The fuel temperature has to controlled so that the viscosity When running on MDF the fuel oil inlet temperature
of the fuel before injection pumps is stable and according should be kept at maximum of +45°C. When running long
to the limits specified in chapter General data and outputs. periods with low load this requires an external MDF cooler
(1E04) to be installed.
6.1.2. Black out starting
6.2.2. Internal fuel system
In installations where the stand-by engines can be fed from
the diesel fuel day tank, sufficient fuel pressure for a safe The standard system comprises the following built-on
start must also be ensured in the case of a black-out. This equipment:
can be done with: • fuel injection pumps
• a gravity tank min. 15 m above the engine centerline • injection valves
• a pneumatic emergency pump (1P11) • pressure control valve in the outlet pipe
• an electric motor driven pump (1P11) fed from an emer- Controlled leak fuel from the injection valves and the in-
gency supply jection pumps is drained to atmospheric pressure (Clean
If the engines are equipped with engine driven fuel feed leak fuel system). The clean leak fuel can be reconducted to
pumps, see heading for MDF installations. the system without treatment. The quantity of leak fuel is
given in chapter for Technical data. Possible uncontrolled
6.1.3. Number of engines leak fuel and spilled water and oil is separately drained from
the hot-box and shall be led to a sludge tank (“Dirty” leak
In multi-engine installations, the following main principles fuel system).
should be followed when dimensioning the fuel system:
• A separate fuel feed circuit is recommended for each
propeller shaft (two-engine installations); in four- engine
installations so that one engine from each shaft is fed
from the same circuit.

Marine Project Guide W20 - 1/2002 33

 6. Fuel oil system

Dimensions of fuel pipe connections on the engine

Code Description Size Pressure class Standard
101 Fuel inlet, HFO OD18 PN250 DIN 2353
101 Fuel inlet, MDF OD28 PN250 DIN 2353
102 Fuel outlet, HFO OD18 PN250 DIN 2353
102 Fuel outlet, MDF OD28 PN250 DIN 2353
103 Leak fuel drain, clean fuel OD18 - DIN 2391
1041 Leak fuel drain, dirty fuel OD22 - DIN 2391
1043 Leak fuel drain, dirty fuel OD18 - DIN 2391
105 Fuel stand-by connection OD22 PN250 DIN 2353

Internal fuel system, MDF (4V76F5881)

System components Pipe connections, engine

01 Injection pump 101 Fuel inlet
02 Injection valve 102 Fuel outlet
03 Leak fuel oil system with level alarm 103 Leak fuel drain, clean fuel
04 Duplex fine filter 104 Leak fuel drain, dirty fuel
05 Engine driven fuel feed pump 105 Fuel stand-by connection
06 Pressure regulating valve

34 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

Internal fuel system, HFO (4V76F5880)

System components Pipe connections

01 Injection pump 101 Fuel inlet
02 Injection valve 102 Fuel outlet
03 Leak fuel oil system with level alarm 103 Leak fuel drain, clean fuel
04 Adjustable orifice 104 Leak fuel drain, dirty fuel
05 Pulse damper

Marine Project Guide W20 - 1/2002 35

 6. Fuel oil system

Engine driven fuel feed pump Feed pump, separator (1P02)

If the engine is equipped with an engine driven gear type The use of a screw pump is recommended. The pump
fuel feed pump, the day tank shall be arranged so that the should be separate from the separator and electrically
minimum level always remains above the top of the engine. driven.
This arrangement enables deaeration of the circuit and Design data:
minimizes the risk of sucking air into the system, if there is The pump should be dimensioned for the actual fuel qual-
a leakage e.g. in a pipe joint. Special measures for black-out ity and recommended throughput through the separator.
start are not required. The flow rate through the separator should not exceed the
maximum fuel consumption by more than 10%. No con-
6.2.3. External fuel system trol valve should be used to reduce the flow of the pump.
General Operating pressure, max. 0.5 Mpa (5 bar)
The design of the external fuel system may vary from ship Operating temperature 40°C
to ship but every system should provide well cleaned fuel Preheater, separator (1E01)
with the correct temperature and pressure to each engine.
Fuels having a viscosity higher than 5 mm²/s (cSt) at 50°C
Main and auxiliary engines are recommended to be con- need preheating before the separator. For MDF the pre-
nected to separate circuits. heating temperature should be according to the separator
Filling, transfer and storage supplier.
The filling methods of the bunker tanks depend on the off MDF separator (1N05)
board facilities available. The fuel oil separator should be sized according to the rec-
The ship must have means to transfer the fuel from bunker ommendations of the separator supplier.
tanks to setting tanks and between the bunker tanks in or- For max viscosity 11 mm²/s (cSt) at 50°C fuels a flow rate
der to balance the ship. of 80% and a preheating temperature of 45°C are recom-
The amount of fuel in the bunker tanks depends on the to- mended.
tal fuel consumption of all consumers onboard, maximum Sludge tank, separator (1T05)
time between bunkering and the decided margin.
The sludge tank should be placed below the separators and
Separation as close as possible. The sludge pipe should be continu-
Even if the fuel to be used is marine diesel fuel or gas oil ously falling without any horizontal parts.
only, it is recommended to install a separator between the Fuel feed system
bunker tanks and the settling tank or day tanks, as there
should be some means of separating water from the fuel. For marine diesel fuel (MDF) and fuels having a viscosity
of less than 115 mm²/s(cSt)/50°C and if the tanks can be
Settling tank, MDF (1T10) located high enough to prevent cavitation in the fuel feed
In case where MDF is the only fuel onboard the settling pump, a system with an open de-aeration tank may be in-
tank should normally be dimensioned to ensure fuel supply stalled.
for min. 24 operating hours when filled to maximum. The General
tank should be designed to provide the most efficient
sludge and condensed water rejecting effect. The bottom It has to be possible to shut-off the heating of the pipes
of the tank should have slope to ensure good drainage. when running with MDF (the tracing pipes to be grouped
MDF settling tank does not need heating coils or insula- together according to their use). Any provision to change
tion. the type of fuel during operation should be designed to ob-
tain a smooth change in fuel temperature and viscosity, e.g.
The temperature in the MDF settling tank should be be-
via a mixing tank. When changing from HFO to MDF, the
tween 20 - 40°C.
viscosity at the engine should be above 2.8 mm²/s(cSt) and
Separator unit, MDF (1N05) not drop below 2.0 mm²/s(cSt) even during short transient
conditions. In certain applications a cooler may be neces-
Suction filter for separator feed pump (1F02)
sary.
A suction filter shall be fitted to protect the feed pump.
The filter can be either a duplex filter with change over Day tank, MDF (1T06)
valves or two separate simplex filters. The design of the fil- The diesel fuel day tank is dimensioned to ensure fuel sup-
ter should be such that air suction cannot occur. ply for 12...14 operating hours when filled to maximum*.
• fineness 0.5 mm

36 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

*Note anyhow that SOLAS Chapter II-1 Part C Regula- They should then be located in the fuel feed line before the
tion 26 states that “Two fuel oil service tanks for each type automatic filter and in the return line after the engine. An
of fuel used on board necessary for propulsion and vital automatically opening by-pass line around the consump-
systems or equivalent arrangements shall be provided on tion meter is recommended in case of possible clogging.
each new ship, with the capacity of at least 8 h at maximum
Cooler/Heater
continuos rating of the propulsion plant and normal oper-
ating load at sea of the generator plant. This paragraph Since the viscosity before the engine must stay between the
applies only to ships constructed on or after 1 July 1998.” allowed limits stated in the Chapter for General data and
outputs, a heater might be necessary in case the day tank
Suction strainer, MDF (1F03) temperature is low. Cooler is needed where long periods of
A suction strainer with a fineness of 0.5 mm should be in- low load operation is expected since fuel gets heated in the
stalled for protecting the feed pumps. The strainer may be engine during the circulation. The cooler is located in the
either of duplex type with change over valves or simplex return line after the engine(s). LT-water is normally used as
strainers in parallel. The design should be such that air suc- cooling medium.
tion is prevented.
Leak fuel tank, clean fuel (1T04)
Circulation pump, MDF (1P03) Clean leak fuel drained from the injection pumps can be re-
The circulation pump maintains the pressure before the used without repeated treatment. The fuel should be col-
engine. It is recommended to use screw pump as circula- lected in a separate clean leak fuel tank and, from there, be
tion pump. pumped to the settling tank. The pipes from the engine to
Design data: the drain tank should be arranged continuously sloping.
• capacity to cover the total consumption of the engines Leak fuel tank, dirty fuel (1T07)
and the flush quantity of a possible automatic filter Under normal operation no fuel should leak out of the
• the pumps should be placed so that a positive static pres- dirty system. Fuel, water and oil is drained only in the event
sure of about 30 kPa is obtained on the suction side of of unattended leaks or during maintenance. Dirty leak fuel
the pumps. pipes shall be led to a sludge tank.
Pressure control (overflow) valve, MDF (1V02) Fuel feed unit
The pressure control valve maintains the pressure in the Fuel feed equipment can also be combined to form a unit.
feed line directing the surplus flow to the suction side of
the feed pump.
set point 0.4 Mpa (4 bar)
Fuel consumption meter
If a fuel consumption meter is required, it should be fitted
in the day tank feed line. In case of individual engine fuel
consumption metering is required, two meters per engine
need to be installed.

Marine Project Guide W20 - 1/2002 37

 6. Fuel oil system

Fuel feed system, main engine (3V76F5884)

System components Pipe connections

1F07 Suction strainer, MDF 101 Fuel inlet
1P08 MDF stand by pump 102 Fuel outlet
1T04 Leak fuel tank, clean fuel 103 Leak fuel drain, clean fuel
1T06 Day tank, MDF 1041 Leak fuel drain, dirty fuel free end
1T07 Leak fuel tank, dirty fuel 1043 Leak fuel drain, dirty fuel flywheel end
105 Fuel stand-by connection

38 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

6.3. HFO installations Fuel heating

In ships intended for operation on heavy fuel, steam or
6.3.1. General thermal oil heating coils must be installed in all tanks.
In ships intended for operation on heavy fuel, steam or All heat consumers should be considered:
thermal oil heating coils must be installed in the bunker, • bunker tanks
settling and day tanks, so that it is possible to maintain a • day and settling tanks
temperature of 40 - 50°C (or even higher temperature, de-
pending on the pour point and viscosity of the heavy fuel • trace heating
used). • fuel separators
Normally the heating coils are dimensioned on basis of the • fuel booster modules
heat transfer required for raising the temperature of the The heating requirement of tanks is calculated from the
tank to the above temperature in a certain time, e.g. 1°C/h, maximum heat losses from the tank and from the require-
as well as on the heat losses when maintaining the tank at ment of raising the temperature by typically 1°C/h. The
that temperature. heat loss can be assumed to be 15 W/m²°C between tanks
All tanks, from, which heavy fuel is pumped, are to be kept and shell plating against the sea and 3 W/m²°C between
5 - 10°C above the pour point. Max. allowed pour point for tanks and cofferdams. The heat capacity of fuel oil can be
allowed fuels is +30°C. taken as 2 kJ/kg°C.
The design of the external fuel system may vary from ship For pumping, the temperature of fuel storage tanks must
to ship, but every system should provide well cleaned fuel always be maintained 5 - 10°C above the pour point - typi-
with the correct temperature and pressure to each engine. cally at 40 - 50°C. The heating coils can be designed for a
When using heavy fuel it is most important that the fuel is temperature of 60°C.
properly cleaned from solid particles and water. In addition The day and settling tank temperatures are usually in the
to the harm poorly centrifuged fuel will do to the engine, a range 50 - 80°C. A typical heating capacity is 12 kW each.
high content of water may cause big problems to the heavy
Trace heating of insulated fuel pipes requires about 1.5
fuel feed system. For the feed system, well-proven compo-
W/m²°C. The area to be used is the total external area of
nents should be used.
the fuel steel pipe.
The fuel treatment system should comprise at least one
Fuel separators require typically 7 kW/installed engine
settling tank and two (or several) separators to supply the
MW and booster units 30 kW/installed engine MW. See
engine(s) with sufficiently clean fuel. When operating on
also formulas presented later in this chapter.
heavy fuel the dimensioning of the separators is of greatest
importance and therefore the recommendations of the
separator designer should be closely followed.
When designing the piping diagram, the procedure to flush
the fuel system with service air should be clarified and pre-
sented in the diagram.
The vent pipes of all tanks containing heavy fuel oil must
be continuously upward sloping.
Remarks:
When dimensioning the pipes of the fuel oil system com-
mon known rules for recommended fluid velocities must
be followed.
The fuel oil pipe connections on the engine can be smaller
than the pipe diameter on the installation side.

Marine Project Guide W20 - 1/2002 39

 6. Fuel oil system

Example: A fuel oil with a viscosity of 380 mm²/s (cSt) (A) To obtain temperatures for intermediate viscosities, draw
at 50°C (B) or 80 mm²/s (cSt) at 80°C (C) must be pre- a line from the known viscosity/temperature point in par-
heated to 115 - 130°C (D-E) before the fuel injection allel to the nearest viscosity/temperature line in the dia-
pumps, to 98°C (F) at the centrifuge and to minimum 40°C gram.
(G) in the storage tanks. The fuel oil may not be pumpable Example: Known viscosity 60 mm²/s (cSt) at 50°C (K).
below 36°C (H). The following can be read along the dotted line: viscosity at
80°C = 20 mm²/s (cSt), temperature at fuel injection
pumps 74 - 87°C, centrifuging temperature 86°C, mini-
mum storage tank temperature 28°C.

Fuel oil viscosity-temperature diagram for determining the preheating temperatures of fuel oils
(4V92G0071a)

40 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

6.3.2. Internal fuel system 6.3.3. External fuel system

The standard system comprises the following built-on General
equipment: The engine is designed for continuous heavy fuel opera-
• heavy fuel injection pumps tion. It is, however, possible to operate the engine on diesel
• injection valves fuel without making any alterations.
• pressure control orifice in the outlet pipe The engine can be started and stopped on heavy fuel pro-
vided that the engine and the fuel system are preheated to
Leak fuel from the injection valves and the injection
operating temperature. Switch-over from HFO to MDF
pumps is drained to atmospheric pressure (Clean leak fuel
for start and stop is not recommended.
system). The clean leak fuel can be reconducted to the sys-
tem without treatment. The quantity of leak fuel is given in
chapter for Technical data. Possible uncontrolled leak fuel
and spilled water and oil is separately drained from the
hot-box and shall be led to a sludge tank (“Dirty” leak fuel
system).

Marine Project Guide W20 - 1/2002 41

 6. Fuel oil system

Fuel transfer and separating system (3V76F5882)

System components
1E01 Heater 1T01 Bunker tank
1F02 Suction filter 1T02 Settling tank, HFO
1P02 Feed pump 1T03 Day tank, HFO
1P09 Transfer pump, HFO 1T04 Overflow tank
1P10 Transfer pump, MDF 1T05 Sludge tank
1S01 Separator, HFO 1T06 Day tank, MDF
1S02 Separator, MDF 1T10 Settling tank, MDF

42 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

Note that settling and day tanks have been drawn separate Separator unit (1N05)
in order to show overflow pipe. They normally have com- Suction filter for separator feed pump (1F02)
mon intermediate wall and insulation.
A suction filter shall be fitted to protect the feed pump.
Filling, transfer and storage The filter should be equipped with a heating jacket in case
The filling methods of the bunker tanks depend on the off the installation place is cold. The filter can be either a du-
board facilities available. plex filter with change over valves or two separate simplex
The ship must have means to transfer the fuel from filters. The design of the filter should be such that air suc-
tion cannot occur.
bunker tanks to setting tanks and between the bunker
tanks in order to balance the ship. • fineness 0.5 mm
The amount of fuel in the bunker tanks depends on the to- Feed pump, separator (1P02)
tal fuel consumption of all consumers onboard, maximum
The pump should be dimensioned for the actual fuel qual-
time between bunkering and the decided margin.
ity and recommended throughput through the separator.
Separation The flow rate through the separator should not exceed the
maximum fuel consumption by more than 10%. No con-
Heavy fuel (residual, and mixtures of residuals and distil-
trol valve should be used to reduce the flow of the pump.
lates) must be cleaned in an efficient centrifugal separator
before entering the day tank. Design data:

Separator mode of operation • delivery pressure (max.) 0.2 Mpa (2 bar)

• operating temperature 100°C
Two separators, both of the same size, should be installed.
The capacity of one separator to be sufficient for the total viscosity for dimensioning electric motor
fuel consumption. The other (stand-by) separator should 1000 mm²/s (cSt)
also be in operation all the time. Preheater, separator (1E01)
It is recommended that conventional separators with grav- The preheater is normally dimensioned according to the
ity disc are arranged for operation in series, the first as a pu- feed pump capacity and a given settling tank temperature.
rifier and the second as a clarifier. This arrangement can be The heater surface temperature must not be too high in or-
used for fuels with a density up to max. abt. 991 kg/m³ at der to avoid cracking of the fuel.
15°C.
The heater should be controlled to maintain the fuel tem-
Separators with controlled discharge of sludge (without perature within ± 2°C. The recommended preheating tem-
gravity disc) operating on a continuous basis can handle fu- perature for heavy fuel is 98°C.
els with densities exceeding 991 kg/m³ at 15°C. In this case
Design data:
the main and stand-by separators should be run in parallel.
The required minimum capacity of the heater is:
Settling tank, HFO (1T02)
P(kW) = m(l/h) Dt(°C) / 1700
The settling tank should normally be dimensioned to en-
P(kW) = heater capacity
sure fuel supply for min. 24 operating hours when filled to
maximum. The tank should be designed to provide the m = capacity of the separator feed pump
most efficient sludge and water rejecting effect. The bot- Dt = temperature rise in heater
tom of the tank should have slope to ensure good drainage. For heavy fuels Dt = 48°C can be used, i.e. a settling tank
The tank is to be provided with a heating coil and should be temperature of 50°C.
well insulated. Fuels having a viscosity higher than 5 mm²/s (cSt) at 50°C
To ensure constant fuel temperature at the separator, the need preheating before the separator.
settling tank temperature should be kept stable. The tem-
perature in the settling tank should be between 50...70°C.
The min. level in the settling tank should be kept as high as
possible. In this way the temperature will not decrease too
much when filling up with cold bunker.

Marine Project Guide W20 - 1/2002 43

 6. Fuel oil system

HFO separator (1S01) Maximum recommended viscosity in the day tank is 140
The fuel oil separator should be sized according to the rec- mm²/s (cSt). Due to the risk of wax formation, fuels with a
ommendations of the separator supplier. viscosity lower than 50 mm²/s (cSt)/50°C must be kept at
higher temperatures than what the viscosity would require.
Based on a separation time of 23 or 23.5 h/day, the nomi-
nal capacity of the separator can be estimated acc. to the Fuel viscosity Minimum day tank
following formula: (mm²/s (cSt) at 100°C) temperature (°C)
55 80
P[kW] · b · 24[h]
Q [l/h] = 35 70
r · t[h] 25 60
*Note anyhow that SOLAS Chapter II-1 Part C Regula-
where: tion 26 states that “Two fuel oil service tanks for each type
of fuel used on board necessary for propulsion and vital
P = max. continuous rating of the diesel engine systems or equivalent arrangements shall be provided on
b = specific fuel consumption + 15% safety margin each new ship, with the capacity of at least 8 h at maximum
r = density of the fuel continuos rating of the propulsion plant and normal oper-
t = daily separating time for selfcleaning separator (usually ating load at sea of the generator plant. This paragraph
= 23 h or 23.5 h) applies only to ships constructed on or after 1 July 1998.”
The flow rates recommended for the separator and the Fuel feed unit (1N01)
grade of fuel in use must not be exceeded. The lower the A completely assembled fuel feed unit can be supplied as
flow rate the better the separation efficiency. an option.
Sludge tank, separator (1T05) This unit normally comprises the following equipment:
The sludge tank should be placed below the separators and • two suction strainers
as close as possible. The sludge pipe should be continu- • two booster pumps of screw type, equipped with
ously falling without any horizontal parts. built-on safety valves and electric motors
Fuel feed system • one pressure control/overflow valve
General • one pressurized de-aeration tank, equipped with a level
switch operated vent valve
The fuel feed system for HFO shall be of the pressurized
type in order to prevent foaming in the return lines and cav- • two circulation pumps, same type as above
itation in the circulation pumps. • two heaters, steam, electric or thermal oil (one in opera-
The heavy fuel pipes shall be properly insulated and tion, the other as spare)
equipped with trace heating, if the viscosity of the fuel is • one automatic back-flushing filter with by-pass filter
180 mm²/s (cSt)/50°C or higher. It shall be possible to
• one viscosimeter for the control of the heaters
shut-off the heating of the pipes when running MDF (the
tracing pipes to be grouped together according to their • one steam or thermal oil control valve or control cabinet
use). for electric heaters
Any provision to change the type of fuel during operation • one thermostat for emergency control of the heaters
should be designed to obtain a smooth change in fuel tem- • one control cabinet with starters for pumps, automatic
perature and viscosity, e.g. via a mixing tank. When chang- filter and viscosimeter
ing from HFO to MDF, the viscosity at the engine should
• one alarm panel
be above 2.8 mm²/s(cSt) and not drop below 2.0
mm²/s(cSt) even during short transient conditions. In cer- The above equipment is built on a steel frame, which can
tain applications a cooler may be necessary. be welded or bolted to its foundation in the ship. All heavy
fuel pipes are insulated and provided with trace heating.
Day tanks, HFO (1T03)
When installing the unit, only power supply, group alarms
The heavy fuel day tank is usually dimensioned to ensure and fuel, steam and air pipes have to be connected.
fuel supply for about 24 operating hours when filled to
maximum*. The design of the tank should be such that wa-
ter and dirt particles do not accumulate in the suction pipe.
The tank has to be provided with a heating coil and should
be well insulated.

44 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

Fuel feed unit, example (4V76F5613)

3120

1200

Suction strainer HFO (1F06) ther of duplex type with change over valves or simplex
A suction strainer with a fineness of 0.5 mm should be in- strainers in parallel. The design should be such that air suc-
stalled for protecting the feed pumps. The strainer should tion is prevented.
be equipped with a heating jacket. The strainer may be ei-

Marine Project Guide W20 - 1/2002 45

 6. Fuel oil system

Feed pump, HFO (1P04) - alarm 80 kPa (0.8 bar)

The feed pump maintains the pressure in the fuel feed sys- Fuel consumption meter
tem. It is recommended to use a high temperature resistant
If a fuel consumption meter is required, it should be fitted
screw pump as feed pump.
between the feed pumps and the de-aeration tank. An au-
Design data: tomatically opening by-pass line around the consumption
• capacity to cover the total consumption of the engines meter is recommended in case of possible clogging.
and the flush quantity of a possible automatic filter De-aeration tank
• The pumps should be placed so that a positive static The volume of the tank should be about 50 l. It shall be
pressure of about 30 kPa is obtained on the suction side
equipped with a vent valve, controlled by a level switch. It
of the pumps. shall also be insulated and equipped with a heating coil.
- delivery pressure 0.6 Mpa (6 bar) The vent pipe should, if possible, be led downwards, e.g. to
- operating temperature 100°C the overflow tank.
- viscosity for dimensioning electric motor Circulation pump, HFO (1P06)
1000 mm²/s (cSt)
The purpose of this pump is to circulate the fuel in the sys-
Pressure control (overflow) valve HFO tem and to maintain the pressure stated in the chapter for
The pressure control valve maintains the pressure in the Technical data at the injection pumps. It also circulates the
de-aeration tank directing the surplus flow to the suction fuel in the system to maintain the viscosity, and keeps the
side of the feed pump. piping and injection pumps at operating temperature.
• set point 0.3…0.5 MPa (3...5 bar) The feed pump capacity should be sufficient to prevent
pressure drop during the flushing of the automatic filter if
Automatically cleaned fine filter, HFO (1F08) installed on the pressure side of this pump.
The use of automatic back-flushing filters is recom- Design data:
mended, installed between the feeder pumps and the
• capacity constant (see below) times the total consump-
deaeration tank in parallel with an insert filter as the tion of the engines and the flushing of the automatic fil-
stand-by half.
ter
For back-flushing filters the feed pump capacity should be
• capacity constant
sufficient to prevent pressure drop during the flushing op-
eration. - operating pressure 1 MPa (10 bar)
Design data: - operating temperature 150°C
• fuel oil according to spec. - viscosity (for dimensioning
the el. motor) 500 mm²/s (cSt)
• operating temperature 0...150°C
Heater
• preheating from 25 mm²/s
(cSt)/100°C The heater(s) is normally dimensioned to maintain an in-
jection viscosity of 14 mm²/s (cSt) according to the maxi-
• flow circulation pump capacity
mum fuel consumption and a given day tank temperature.
• operating pressure 0.1 MPa (10 bar) To avoid cracking of the fuel the surface temperature in
• design pressure 0.16 Mpa (16 bar) the heater must not be too high. The surface power of elec-
• test pressure fuel side 0.2MPa(20 bar) tric heaters must not be higher than 1.5 W/cm2. The out-
heating jacket 0.1 Mpa put of the heater shall be controlled by a viscosimeter. As a
(10 bar) reserve a thermostat control may be fitted.
• fineness: The set point of the viscosimeter shall be somewhat lower
than the required viscosity at the injection pumps to com-
- back-flushing filter 25 mm (absolute mesh
pensate for heat losses in the pipes.
size)
Design data:
- insert filter 25 mm (absolute mesh
size) The required minimum capacity of the heater is:
• Maximum recommended pressure drop for normal P(kW) = m(l/h) Dt(°C) / 1700
filters at 14 mm²/s (cSt): P(kW) = heater capacity
- clean filter 20 kPa (0.2 bar) m = evaluated by multiplying the specific fuel consump-
- dirty filter 60 kPa (0.6 bar) tion of the engines by the total max. output of the engines

46 Marine Project Guide W20 - 1/2002

 6. Fuel oil system

Dt = temperature rise, higher with increased fuel viscosity Pressure control valve on the return line
To compensate for heat losses due to radiation the above (1V04)
power should be increased with 10% + 5 kW. This valve controls the pressure in the return line from the
The following values can be used: engine.
Fuel viscosity Temperature rise Leak fuel tank, clean fuel (1T04)
(mm²/s (cSt) at 100°C) in heater (°C) Clean leak fuel drained from the injection pumps can be re-
55 65 (80 in day tank) used without repeated treatment. The fuel should be col-
35 65 (70 in day tank) lected in a separate clean leak fuel tank and, from there, be
pumped to the settling tank. The pipes from the engine to
25 60 (60 in day tank)
the drain tank should be arranged continuously sloping and
Viscosimeter should be provided with heating and insulation.
For the control of the heater(s) a viscosimeter has to be in- Leak fuel tank, dirty fuel (1T07)
stalled. A thermostatic control shall be fitted, to be used as
Under normal operation no fuel should leak out of the
safety when the viscosimeter is out of order. The
dirty system. Fuel, water and oil is drained only in the event
viscosimeter should be of a design, which stands the pres-
of unattended leaks or during maintenance. Dirty leak fuel
sure peaks caused by the injection pumps of the diesel en-
pipes shall be led to a sludge tank and be trace heated and
gine.
insulated.
Design data:
• viscosity range (at injection pumps)
12...24 mm²/s (cSt)
• operating temperature 180°C
• operating pressure 4 MPa (40 bar)
Overflow valve (1V05)
This valve limits the maximum pressure in fuel line to the
engine by relieving the pressure to the return line.

Marine Project Guide W20 - 1/2002 47

 6. Fuel oil system

Fuel feed system, auxiliary engines (3V76F5883)

System components
1E02 Heater 1V02 MDF pressure control valve
1E03 Radiator 1V04 Pressure regulating valve
1F03 Fine filter, HFO 1V05 Overflow valve
1F05 Fine filter, MDF 1V08 3-way change over valve
1F06 Suction filter, HFO 1V09 Change over valve
1F07 Suction strainer, MDF
1F08 Automatic filter
1I01 Flow meter
1I02 Viscosimeter Pipe connections
1P04 Fuel feed pump, HFO 101 Fuel inlet
1P06 Circulation pump 102 Fuel outlet
1P08 MDF pump 103 Leak fuel drain, clean fuel
1T03 Day tank, HFO 1041 Leak fuel drain, dirty fuel free end
1T04 Leak fuel tank, clean fuel 1043 Leak fuel drain, dirty fuel flywheel end
1T06 Day tank, MDF
1T07 Leak fuel tank, dirty fuel
1T08 De-aeration tank

48 Marine Project Guide W20 - 1/2002

 7. Lubricating oil system

7. Lubricating oil system

7.1. General Today’s modern trunk piston diesel engines are stressing
the lubricating oils heavily due to a.o. low specific lubricat-
Each engine should have a separate lubricating oil system ing oil consumption. Also ingress of residual fuel combus-
of its own. Engines operating on heavy fuel should have tion products into the lubricating oil can cause deposit
continuous centrifuging of the lubricating oil. formation on the surface of certain engine components re-
The following equipment is built on the engine as stan- sulting in severe operating problems. Due to this many lu-
dard: bricating oil suppliers have developed new lubricating oil
• Engine driven lubricating oil pump formulations with better fuel and lubricating oil compati-
bility.
• Prelubricating oil pump
If MDF is used as fuel, a lubricating oil with a BN of 10 - 22
• Lubricating oil cooler
is recommended. However, an approved lubricating oil
• Thermostatic valve with a BN of 24 - 30 can also be used, if the desired lower
• Automatic filter BN lubricating oil brand is not included in table below.
• Centrifugal filter Table 7.1. Approved system oils - recommended in
the first place, in gas oil (A) or marine diesel oil (B)
• Pressure control valve installations
The following equipment can be mounted on the engine as
optional: Fuel
Supplier Brand name Viscosity BN
• Stand by pump connections category

The engine sump is normally: Wet BP Energol HPDX40 SAE 40 12 A

Castrol TLX 154 SAE 40 15 A, B
Local gauges
TLX 204 SAE 40 20 A, B
Local thermometers should be installed wherever a new
temperature occurs, i.e. before and after heat exchangers, Mobil Mobilgard ADL 40 SAE 40 15 A, B
etc.
Mobilgard 412 SAE 40 15 A, B
Pressure gauges should be installed on the suction and dis-
Gadinia Oil 40
charge side of each pump. Shell SAE 40 12 A
(SL0391)
Sirius FB Oil 40 SAE 40 13 A
7.2. Lubricating oil quality
Engine lubricating oil
The lubricating oils mentioned in table below are repre-
The system oil should be of viscosity class SAE 40 (ISO senting a new detergent/dispersant additive chemistry and
VG 150). have shown good performance in Wärtsilä engines. These
The alkalinity, BN, of the system oil should be 30 - 55 lubricating oils are recommended in the first place in order
mg/KOH/g in heavy fuel use; higher at higher sulphur to reach full service intervals.
content of the fuel. It is recommended to use BN 40 lubri-
cants with category C fuels. The use of high BN (50 - 55) lu-
bricants in heavy fuel installations is recommended, if the
use of BN 40 lubricants causes short oil change intervals.

Marine Project Guide W20 - 1/2002 49

 7. Lubricating oil system

Table 7.2. Approved system oils: lubricating oils with improved detergent/dispersant additive chemistry - heavy
fuel (C), recommended in the first place

Supplier Brand name Viscosity BN Fuel category

BP Energol IC-HFX 304 SAE 40 30 A, B, C
Energol IC-HFX 404 SAE 40 40 A, B, C
Energol IC-HFX 504 SAE 40 50 A, B, C
Caltex Delo 3000 Marine SAE 40 SAE 40 30 A, B, C
Delo 3400 Marine SAE 40 SAE 40 40 A, B, C
Delo 3550 Marine SAE 40 SAE 40 55 A, B, C
Castrol TLX 304 SAE 40 30 A, B, C
TLX 404 SAE 40 40 A, B, C
TLX 504 SAE 40 50 A, B, C
TLX 554 SAE 40 55 A, B, C
Chevron Delo 3000 Marine 40 SAE 40 30 A, B, C
Delo 3400 Marine 40 SAE 40 40 A, B, C
Delo 3550 Marine 40 SAE 40 55 A, B, C
Elf Lub Marine Aurelia 4030 SAE 40 30 A, B, C
Aurelia XT 4040 SAE 40 40 A, B, C
Aurelia XT 4055 SAE 40 55 A, B, C
Esso Exxmar 30 TP 40 PLUS SAE 40 30 A, B, C
Exxmar 40 TP 40 PLUS SAE 40 40 A, B, C
Exxmar 50 TP 40 PLUS SAE 40 50 A, B, C
Fina Stellano S 430 SAE 40 30 A, B, C
Stellano S 440 SAE 40 40 A, B, C
Stellano S 455 SAE 40 55 A, B, C
Mobil Mobilgard 430 SAE 40 30 A, B, C
Mobilgard 440 SAE 40 40 A, B, C
Mobilgard 50 M SAE 40 50 A, B, C
Mobilgard SP 55 SAE 40 55 A, B, C
Shell Argina T 40 SAE 40 30 A, B, C
Argina X 40 SAE 40 40 A, B, C
Argina XL 40 SAE 40 50 A, B, C
Texaco Taro 30 DP 40 SAE 40 30 A, B, C
Taro 40 XL 40 SAE 40 40 A, B, C
Taro 50 XL 40 SAE 40 50 A, B, C

The lubricating oils in table below, representing conven- Table 7.3. Approved system oils: lubricating oils with
tional additive technology, are also approved for use. How- conventional detergent/dispersant additive chemistry
ever, with these lubricating oils, the service intervals will
Supplier Brand name Viscosity BN Fuel category
most likely be shorter.
Esso Exxmar 30 TP 40 SAE 40 30 A, B, C
NB! Different oil brands not to be blended unless ap-
proved by oil supplier and, during guarantee time, by en- Exxmar 40 TP 40 SAE 40 40 A, B, C
gine manufacturer. Neptuno 3000
Repsol SAE 40 30 A, B, C
SAE 40
Neptuno 4000
SAE 40 40 A, B, C
SAE 40

50 Marine Project Guide W20 - 1/2002

 7. Lubricating oil system

7.3. Internal lubricating oil

system
Depending on the type of application the lubricating oil system built on the engine can vary somewhat in design.
Dimensions of lubricating oil pipe connections on the engine

Pipe connections Size Pressure class Standard

202 Lubrication oil outlet (dry sump) DN100 see 4V32A0506
203 Lubrication oil to engine driven pump (dry sump) DN100 see 4V32A0506
205 Lubrication oil to priming pump (dry sump) DN32 PN40 ISO 7005-1
207 Lubrication oil to electric driven pump DN100 PN16 ISO 7005-1
208 Lubrication oil from electric driven pump DN80 PN16 ISO 7005-1
213 Lubrication oil from separator and filling DN32 PN40 ISO 7005-1
214 Lubrication oil to separator and drain DN32 PN40 ISO 7005-1

Internal lubricating oil system (4V76E3854)

Flange for lubricating oil pump (4V32A0506a)

System components
01 Lubricating oil main pump
02 Prelubricating oil pump
03 Lubricating oil cooler
04 Thermostatic valve
05 Automatic filter
06 Centrifugal filter
07 Pressure control valve
08 Turbocharger

Marine Project Guide W20 - 1/2002 51

 7. Lubricating oil system

7.3.1. Lubricating oil pump 7.3.7. Lubricating oil module

The direct driven lubricating oil pump is of the gear type. Lubricating oil module, consisting of filters, thermostatic
The pump is dimensioned to provide sufficient flow even valve and oil cooler, is supported directly from the engine
at low speeds and is equipped with an overflow valve which block.
is controlled from the oil inlet pipe. If necessary, the engine
is provided with pipe connections for a separate, electric
motor driven stand-by pump. 7.4. External circulating oil
Concerning flow rates and pressures, see Technical Data. system
The suction height of the pump should not exceed 4 m. When designing the piping diagram, the procedure to flush
the system should be clarified and presented in the dia-
7.3.2. Prelubricating pump gram.
The prelubricating pump is an electric motor driven con-
stant volume pump equipped with a safety valve. 7.4.1. System oil tank
The pump is of srew type. The dry engine sump has two drain outlets at the flywheel
The pump is used for: end and two at the free end. Two of the drains shall be con-
nected. The pipe connection between the sump and the
• Filling of the engine lubricating oil system before start-
system oil tank should be arranged flexible enough to allow
ing, e.g. when the engine has been out of operation for a
thermal expansion.
long time
Recommendations for the tank design are given in the
• Continuous prelubrication of a stopped engine through
drawing of the engine room arrangement. The tank must
which heated heavy fuel is circulating
not be placed so that the oil is cooled so much that the rec-
• Continuous prelubrication of a stopped diesel engine(s) ommended lubricating oil temperature cannot be ob-
in a multi-engine installation always when any one en- tained. If there is space enough a cofferdam below the tank
gine is running is recommended.
Concerning flow and pressures, see Technical Data. The Design data:
suction height of the built-on prelubricating pump should
• Oil volume 1.2...1.5 l/kW
not exceed 3.5 m.
• Tank filling 75...80%
7.3.3. Lubricating oil cooler
7.4.2. Suction strainer
Lubricating oil cooler is brazed plate cooler and integrated
in the lubricating oil module. If necessary, a suction strainer complemented with mag-
netic rods can be fitted in the suction pipe to protect the lu-
7.3.4. Thermostatic valve bricating oil pump.
The suction strainer as well as the suction pipe diameter
Thermostatic valve is integrated in the lubricating oil mod-
should be amply dimensioned to minimize the pressure
ule.
loss. The suction strainer should always be provided with
alarm for high differential pressure.
7.3.5. Lubricating oil automatic fine filter
• Fineness 0.5...1.0 mm
Lubricating oil fine filter is back flushing automatic filter
whose back flush is led to the centrifugal filter. 7.4.3. Lubricating oil pump, stand-by
• Fine filter (full flow) 25 mm (2P04)
• Safety net (full flow) 100 mm The stand-by lubricating oil pump is normally of screw
type and should be provided with an overflow valve.
7.3.6. Centrifugal filter Design data:
Centrifugal filter is powered by oil flow and filters the Capacity see Technical data
back flush of fine filter. Operating pressure, max 8 bar
Operating temperature, max. 100°C
Lubricating oil viscosity SAE 40

52 Marine Project Guide W20 - 1/2002

 7. Lubricating oil system

7.4.4. Lubrication oil gravity tank 7.5.3. Separator preheater (2E02)

In installations without an engine driven pump it is recom- The preheater can be a steam, thermal oil or an electric
mended to have a lubricating oil gravity tank arrangement heater. The surface temperature of the heater must not
for black-out situations. exceed 150°C in order to avoid coking of the oil.
Design data
7.5. Separation system • For engines with centrifuging during operation, the
heater should be dimensioned for this operating condi-
7.5.1. Separator (2N01) tion. The temperature in the separate system oil tank in
the ship’s bottom is normally 65 - 75°C.
For HFO the separator should be dimensioned for contin-
uous centrifuging. For MDF intermittent centrifuging • For engines with centrifuging stopped engine, the heater
might be sufficient. Each lubricating oil system should should be large enough to allow centrifuging at optimal
have a separator of its own. The separator system must not rate of the separator without heat supply from the diesel
be designed for water mixing when centrifuging. engine.
Each main engine operating on heavy fuel shall have a ded- Note!
icated separator. The heaters are to be provided with safety valves with es-
Auxiliary engines operating on a fuel having a viscosity of cape pipes to a leakage tank so that the possible leakage can
be seen.
max. 35 mm²/s (cSt) / 100°C may have a common separa-
tor. In installations with four or more auxiliary engines two
separators should be installed. 7.5.4. Renovating oil tank(2T04)
The separators should preferably be of a type with con- In case of wet sump engines the oil sump content is
trolled discharge of the bowl to minimize the lubricating oil drained to this tank prior to separation.
losses.
The separators should be dimensioned for continuous op- 7.5.5. Renovated oil tank (2T05)
eration. This tank contains renovated oil ready to be used as a re-
Design data: placement of the oil drained for separation.
• Centrifuging temperature 90 - 95°C
Capacity: 7.6. Filling, transfer and storage
Q = 1.36 P n / t
Where: 7.6.1. Lubricating oil storage tank (2T03)
Q = volume flow [l / h] In engines with wet sump, the lubricating oil may be filled
P = total engine output into the engine, using a hose or an oil can, through the
n = number of through-flows of dry sump system oil crankcase cover or through the separator pipe. The system
tank volume [1 / day]: 5 for HFO, 4 for MDF should be arranged so that it is possible to measure the
filled oil volume.
t = operating time [h / day]: 24 for continuos separator
operation, 23 for normal dimensioning
7.6.2. Used oil handling tank (1T05)
Note!
Det Norske Veritas states in their class rules of July 2001 Sludge tank can be used for the storage of used lubrication
oil.
that come into force 1.1.2002 the following:
(Pt.4 Ch.6 Sec.5 C 203) “For diesel engines burning resid-
ual oil fuel, cleaning of the lubrication oil by means of puri- 7.7. Crankcase ventilation
fiers are to be arranged. These means are additional to system
filters.”
A crankcase vent pipe shall be provided for each engine. If
7.5.2. Separator pump (2P03) the engine has a dry sump and there is a system oil tank, this
tank shall have its own vent pipe. Vent pipes of several en-
The separator pump can be directly driven by the separa- gines and vent pipes of engine crankcases and tanks should
tor or separately driven by an electric motor. The flow not be joined together.
should be adapted to achieve the above mentioned optimal
The connection between the engine and the vent pipe is to
flow.
be flexible.

Marine Project Guide W20 - 1/2002 53

 7. Lubricating oil system

A condensate trap shall be fitted on all vent pipes within 1 - If the engine is equipped with a dry sump and parts of the
2 meters of the engine, see drawing 4V76E2522. lubricating oil system are off the engine, these must be
Recommended size of the vent pipe after the condensate flushed in order to remove any foreign particles before
trap is NS 80 start up.
Pipe connection engine: If an electric motor driven stand-by pump is installed, this
should be used for the flushing. In case only an engine
701 Crankcase air vent DN65, ISO 7005-1, NP16
driven main pump is installed, the ideal is to use for flush-
Crankcase ventilation (4V76E2522) ing a temporary pump of equal capacity as the main pump.
The circuit is to be flushed drawing the oil from the sump
tank pumping it through the off-engine lubricating oil sys-
tem and a flushing oil filter with a mesh size of 34 microns
FROM ENGINE or finer and returning the oil through a hose and a crank-
CRANKCASE
case door to the engine sump.
The flushing pump should be protected by a suction
strainer. Automatic lubricating oil filters, if installed, must
be bypassed during the first hours of flushing.
The flushing is more effective if the lubricating oil is
heated. Furthermore, lubricating oil separators should be
in operation prior to and during the flushing.
The minimum recommended flushing time is 24 hours.
During this time the welds in the lubricating oil piping
CRANKCASE VENT should be gently knocked at with a hammer to release slag
and the flushing filter inspected and cleaned at regular in-
tervals.
Either a separate flushing oil or the approved engine oil
BILGE SLUDGE TANK can be used for flushing. If an approved engine oil is used,
it can be maintained provided that it is separated 4 - 5 times
7.8. Flushing instructions over after the flushing has been terminated and the filter
inserts remain clean from any visible contamination.
If the engine is equipped with a wet oil sump and the com-
plete lubricating oil system is built on the engine, flushing is
not required. The system oil tank should be carefully
cleaned and the oil separated to remove dirt and welding
slag.

54 Marine Project Guide W20 - 1/2002

 7. Lubricating oil system

7.9. System diagrams

Lubricating oil system, auxiliary engines (3V76E3855)

System components Pipe connections

1T05 Sludge tank 213 Lubrication oil from separator and filling
2E02 Heater 214 Lubrication oil to separator and drain
2F03 Suction strainer
2P03 Separator pump
2S01 Separator
2T03 New oil tank
2T04 Renovating oil tank
2T05 Renovated oil tank

Marine Project Guide W20 - 1/2002 55

 7. Lubricating oil system

Lubricating oil system, main engine (3V76E3856)

System components Pipe connections

1T05 Sludge tank 202 Lubrication oil outlet (from oil sump)
2E02 Heater 203 Lubrication oil to engine driven pump
2F02 Automatic filter 208 Lubrication oil from electric driven pump
2F03 Suction strainer 209 Lubrication oil to external filter
2F06 Suction strainer 210 Lubrication oil from external filter
2P03 Separator pump
2P04 Stand-by lubrication oil pump
2S01 Separator
2T01 System oil tank

56 Marine Project Guide W20 - 1/2002

 8. Compressed air system

8. Compressed air system

8.1. General 8.3. Internal starting air system
Compressed air is used to start engines and to provide ac- All engines are equipped with a pneumatic starting motor
tuating energy for safety and control devices. Compressed driving the engine through a gear rim on the flywheel.
air is used onboard also for other purposes with different Table 8.1. Dimensions of starting air pipe connections
pressures. The use of starting air supply for these other on the engine
purposes is limited in the classication regulations.
Pressure
Code Description Size Standard
class
8.2. Compressed air quality
Starting air DIN
301 OD28 PN100
To ensure the functionality of the components in the com- inlet 2353
pressed air system, the compressed air has to be dry and
clean from solid particles and oil. The nominal starting air pressure of 30 bar is reduced to 10
bar with a pressure regulator mounted on the engine.
Internal starting air system (4V76H3460)

System components Pipe connections

01 Turbine starter with pneumatic actuator 301 Starting air inlet
02 Blocking valve, turning gear engaged
03 Pneumatic cylinder at each injection pump
04 Pressure regulator
05 Air container
06 Solenoid valve
07 Safety valve

Marine Project Guide W20 - 1/2002 57

 8. Compressed air system

The compressed air system of the electro- pneumatic It should be noted that the minimum pressures stated in
overspeed trip is connected to the starting air system. For the chapter for technical data assume that this pressure is
this reason, the air supply to the engine must not be closed available at engine inlet.
during operation. The rule requirements of some classification societies are
not precise for multiple engine installations.
8.4. External starting air system Starting air receiver (3T01)
The design of the starting air system is partly determined The starting air receiver should be dimensioned for a nom-
by the rules of the classification societies. Most classifica- inal pressure of 30 bar.
tion societies require the total capacity to be divided over The number and the capacity of the air receivers for pro-
two roughly equally sized starting air receivers and starting pulsion engines depend on the requirements of the classifi-
air compressors. cation societies and the type of installation.
If the inertia of the directly coupled equipment is much
larger than the normal reference equipment used on test-
bed the starting air consumption per start value has to be
increased in relation to total (engine included) inertial
masses involved.

External starting air system (3V76H3461)

System components Pipe connections

3T01 Starting air vessel 301 Starting air inlet
3S01 Oil and water separator
3N02 Starting air compressor

58 Marine Project Guide W20 - 1/2002

 8. Compressed air system

Starting air receiver (3V49A0097)

Connections Size [litres] L D Weight [kg]

A Inlet Ø 38
B Outlet R ¾ in
C Pressure gauge R ¼ in 125 1807 320 150
D Drain R ¼ in 250 1767 480 270
E Drain R ¼ in 500 3204 480 480
F Venting
G Safety valve R ½ in

Marine Project Guide W20 - 1/2002 59

 8. Compressed air system

The starting air receivers are to be equipped with a manual • The starting air pipes should always be drawn with slope
valve for condensate drainage. If the air receivers are and be arranged with manual or automatic draining at
mounted horizontally, there must be an inclination of 3-5° the lowest points.
towards drain valve to ensure efficient draining
Starting air compressor (3N02)
Recommended min. volumes of starting air vessels are:
• At least two starting air compressors must be installed. It
• Single main engine driving CPP 2 x 125 l
is recommended that the compressors are capable of fill-
• Single main engine driving FPP 2 x 125 l ing the starting air receiver from minimum to maximum
• Multiple main engines 2 x 250 l pressure in 15 - 30 minutes. For exact determination of
• 1 - 3 auxiliary engines 2 x 125 l the minimum capacity, the rules of the classification so-
cieties must be followed.
• > 3 auxiliary engines 2 x 250 l
Oil and water separator
• An oil and water separator should always be installed in
the pipe between the compressor and the air receiver.
Depending on the operation conditions of the installa-
tion, an oil and water separator may be needed in the
pipe between the air receiver and the engine.

60 Marine Project Guide W20 - 1/2002

 9. Cooling water system

9. Cooling water system

9.1. General 9.1.2. Approved cooling water treatment
products
Only treated fresh water may be used for cooling the en-
gines. Product Supplier
To allow start on heavy fuel, the cooling water system has Drewgard 4109 Drew Ameroid Marine
to be preheated to a temperature as near to the operating
temperature as possible. Maxigard Division, Ashland
DEWT-NC powder Chemical Company
9.1.1. Water quality Liquidewt Boonton, USA
The cylinder, turbocharger, charge air and oil are all cooled Vecom CWT Diesel QC-2
with fresh water. The pH-value and hardness of the water Dearborn 547 Grace Dearborn Ltd.
should be within normal values (hardness < 10°dH, pH > Widnes, Chesire, U.K
6.5). The chloride and sulphate contents should be as low
Cooltreat 651 Houseman Ltd. Burnham,
as possible (chlorides < 80 mg/l). To prevent rust forma-
tion in the cooling water system, the use of corrosion in- Slough, U.K.
hibitors is mandatory. See the instructions in the Marisol CW Maritech AB,
Instruction Manual.
Kristianstad, Sweden
Shore water is not always suitable. The hardness of shore
Nalco 39 L Nalco Chemical Company
water may be too low, which can be compensated by addi-
tives, or too high, causing scale deposits even with addi- Nalcool 2000 Naperville, Illinois, USA
tives. Nalfleet EWT 9-108 Nalfleet Marine Chemicals
Fresh water generated by a reverse osmosis plant onboard Nalfleet CWT 9-131C Nortwich, Cheshire, U.K.
often has a high chloride content (higher than the permit- Nalcool 2000
ted 80 mg/l) causing corrosion.
RD11 Rohm & Haas
For ships with a wide sailing area a safe solution is to use
RD11M Paris, France
fresh water produced by an evaporator (onboard), using
additives according to the Instruction Manual (important). RD25
Sea-water will cause severe corrosion and deposits forma- Texaco ETX6282 S.A. Arteco N.V. Belgium
tion even in small amounts. Tampereen Prosessi-
Ruostop XM
Rain water is unsuitable as cooling water due to a high oxy- Insinöörit
gen and carbon dioxide content, causing a great risk for Tampere, Finland
corrosion. Dieselguard NB Unitor A/S Kolbotn,
Rocor NB liquid Norway
Vecom CWT Diesel Vecom Holding B.V.
Maassluis, Holland

Glycol
Use of glycol in the cooling water is not recommended. It
is however possible to use up to 10% glycol without engine
derating. For higher concentrations the engine shall be de-
rated 0.67% for each percentage unit exceeding 10.

Marine Project Guide W20 - 1/2002 61

 9. Cooling water system

Table 9.1. Impeller diameters and nominal flows of

9.2. Internal cooling water engine driven HT & LT pumps
system
Engine speed HT impeller LT impeller
Engine
9.2.1. Charge air cooler [RPM] [Ø mm] [Ø mm]
The charge air cooler built on the engine is of the insert 4L20 720 170 170
type with removable cooler insert.
750 170 170
Design data:
900 180 187
• See Technical data
1000 170 170
9.2.2. Engine driven circulating cooling 5L20 900 187 187
water pumps
1000 170 170
The LT and HT circuit circulating pumps are always en-
gine driven. The pumps are centrifugal pumps driven by 6L20 720 175 175
the engine crankshaft through a gear transmission. 750 175 175
The HT and LT water pump impeller diameters and corre- 900 187 187
sponding pump curves are presented in the following ta-
bles. 1000 175 175
On request, connections for electric motor driven 8L20 720 180 180
stand-by pumps can be provided.
750 180 180
Material:
900 191 197
• housing cast iron
1000 180 187
• impeller bronze
9L20 720 180 180
• shaft stainless steel
• sealing mechanical 750 180 180
Capacities are according to Chapter for Technical data and 900 191 197
the pump curves below. 1000 180 187

ø170 IMPELLER ø175 IMPELLER

25 25

750 rpm 750 rpm

1000 rp m
20 1000 rp m 20
720 rpm
720 rpm

15
Head [m ]

15
Head [m ]

10
10

5
5

0
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
Flow [m ³/h]
Flow [m ³/h]

62 Marine Project Guide W20 - 1/2002

 9. Cooling water system

ø180 IMPELLER ø187 IMPELLER

30 30
750 rpm
1000 rp m
25 1000 rp m 25
900 rpm
720 rpm
20 900 rpm 20
Head [m ]

Head [m ]
15 15

10 10

5 5

0 0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Flow [m ³/h] Flow [m ³/h]

ø191 IMPELLER ø197 IMPELLER

25 30
900 rpm
900 rpm
25
20

20
15
Head [m ]

Head [m ]

15

10
10

5
5

0 0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85

Flow [m ³/h] Flow [m ³/h]

38°C as fully closed and 50°C as fully open and it is of the

9.2.3. Engine driven sea water pump direct acting type.
(4P11)
For main engines (only) an engine driven sea-water pump 9.2.5. Thermostatic valve HT-circuit
is available: (4V01)
Capacity [m³/h]: The thermostatic valve for the HT-circuit is arranged to
4L20: 40 control the outlet temperature of the water. It is of the di-
5L20: 60 rect acting type.
6L20: 60 • set point of the
8L20: 104 HT-thermostatic valve 91°C
9L20: 104
Head about 20 meters water column 9.2.6. Lubricating oil cooler (2E01)

9.2.4. Thermostatic valve LT-circuit The lubricating oil cooler is cooled by fresh water and con-
nected in series with the charge air cooler.
(4V03)
The thermostatic valve for the LT-circuit is arranged to
control the outlet temperature of the water on engines. The
thermostatic valve has one fixed set point of 49°C with

Marine Project Guide W20 - 1/2002 63

 9. Cooling water system

Dimensions of water pipe connections on the engine

Pipe connections Size Pressure class Standard

401 HT-water inlet DN65 PN16 ISO 7005-1
402 HT-water outlet DN65 PN16 ISO 7005-1
404 HT-water air vent OD12 PN250 DIN 2353
406 Water from preheater to HT-circuit OD28 PN100 DIN 2353
408 HT-water from stand-by pump DN65 PN16 ISO 7005-1
411 HT-water drain M10*1 - Plug
451 LT-water inlet DN80 PN16 ISO 7005-1
452 LT-water outlet DN80 PN16 ISO 7005-1
454 LT-water air vent from air cooler OD12 PN250 DIN 2353
457 LT-water from stand-by pump DN80 PN16 ISO 7005-1
464 LT-water drain M18*1.5 - Plug

Internal cooling water system (4V76C5048)

System components
01 HT-cooling water pump
02 LT-cooling water pump
03 Charge air cooler
04 Lubrication oil cooler
05 HT-thermostatic valve
06 LT-thermostatic valve
07 Adjustable orifice

64 Marine Project Guide W20 - 1/2002

 9. Cooling water system

9.3. External cooling water In case of fresh water central cooler is used for both LT
and HT water the fresh water flow can be calculated with
system the following formula:
The fresh water pipes should be designed to minimize the
flow resistance in the external piping. Galvanized pipes 3.6 · F
should not be used for fresh water. q = qLT +
4.19 · (Tout - Tin)
Ships (with ice class) designed for cold sea-water should
have temperature regulation with a recirculation back to
the sea chest: where:
q[m³/h]= total fresh water flow
• for heating of the sea chest to melt ice and slush, to avoid
clogging the sea-water strainer qLT [m³/h]= nominal LT pump capacity
• to increase the sea-water temperature to enhance the F [kW]= heat dissipated to HT water
temperature regulation of the LT-water Tout = HT water temperature after engine (91°C)
Tin = HT water temperature after cooler (38°C)
9.3.1. Sea water pump (4P11)
• Pressure drop on fresh water side, max.
The sea-water pumps are usually electrically driven. The 60 kPa (0.6 bar)
capacity of the pumps is determined by the type of coolers If the flow resistance in the external pipes is high it should
used and the heat to be dissipated. be observed when designing the cooler.
• Sea-water flow acc. to cooler manufac-
9.3.2. Fresh water central cooler (4E08) turer, normally 1.2 - 1.5
The fresh water cooler can be of either tube or plate type. x the fresh water flow
Due to the smaller dimensions the plate cooler is normally • Pressure drop on sea-water side, norm.
used. The fresh water cooler can be common for several 80-140 kPa (0.8 - 1.4 bar)
engines, also one independent cooler per engine is used.
• Fresh water temperature after cooler (before engine),
Design data: max. 38°C.
• Fresh water flow see Technical Data see Technical Data
• Safety margin to be added 15% + margin for
fouling
See also the table showing example coolers with calcula-
tion data.

Marine Project Guide W20 - 1/2002 65

 9. Cooling water system

Central cooler, main dimensions (4V47E0188b)

Engine Cooling water Sea-water Measures Weight

Type [RPM] Flow Tcw, in Tcw, out Flow Tsw, Tsw, out A B C Dry Wet [kg]
[m³/h] [°C] [°C] [m³/h] in [°C] [°C] [mm] [mm] [mm] [kg]
750 22 52.1 38 30 32 42.6 80 505 695 270 287
4L20
1000 27 54.3 38 36 32 44.3 106 505 695 275 298
5L20 1000 33 52.9 38 44 32 43.2 121 655 845 280 306
750 33 52 38 44 32 42.6 121 655 845 280 306
6L20
1000 40 53.3 38 53 32 43.5 150 655 845 288 321
750 44 52 38 59 32 42.6 156 655 845 289 323
8L20
1000 53 53.6 38 71 32 43.8 198 655 845 298 341
750 49 52.1 38 67 32 42.7 186 655 845 293 336
9L20
1000 59 53.7 38 80 32 43.8 221 905 1095 305 354

66 Marine Project Guide W20 - 1/2002

 9. Cooling water system

9.3.3. Stand-by circulating cooling water 9.3.6. Preheating

pumps
Engines started and stopped on heavy fuel and all engines
The pumps should be centrifugal pumps driven by an elec- on which high load will be applied immediately after start
tric motor. Capacities according to Chapter for Technical (stand-by generating sets) have to be preheated as close to
data. the actual operating temperature as possible, or minimum
60°C. Preheating is however, recommended for all en-
9.3.4. Expansion tank gines, also main engines running on MDF only.

The expansion tank should compensate for volume The energy required for heating of the HT-cooling water in
the main and auxiliary engines can be taken from a running
changes in the cooling water system, serve as venting ar-
engine or a separate source. In both cases a separate circu-
rangement and provide sufficient static pressure for the
lating pump should be used to ensure the circulation. If the
cooling water circulating pumps.
cooling water systems of the main and auxiliary engines are
Design data: separated from each other in other respects, the energy is
• pressure from the expansion tank recommended to be transmitted through heat exchangers.
0.7...1.5 bar For installations with several engines the preheater unit
• volume min. 10% of the system can be chosen for heating up two engines. The heat from a
Concerning engine water volumes, see Chapter for Tech- running engine can be used and therefore the power con-
nical data. sumption of the heater will be less than the nominal capac-
ity.
The tank should be equipped so that it is possible to dose
water treatment agents. Heater (4E05)
The vent pipe of each engine should be drawn to the tank Steam, electrical or thermal oil heaters can be used.
separately, continuously rising, and so that mixing of air
Design data:
into the water cannot occur (the outlet should be below
the water level). • preheating temperature min. 60°C
The expansion tank is to be provided with inspection de- • required heating power 2 kW/cyl.
vices. Preheating pump (4P04)
9.3.5. Drain tank (4T04) Design data of the pump:
• capacity 0.3 m³/h x cyl.
It is recommended to provide a drain tank to which the en-
gines and coolers can be drained for maintenance so that • pressure abt. 80 kPa (0.8 bar)
the water and cooling water treatment can be collected and Preheating unit (4N01)
reused. For the water volume in the engine, see Technical
data (HT-circuit). A complete preheating unit can be supplied as option. The
unit comprises:
Most of the cooling water in the engine can be recovered
from the HT-circuit. • electric or steam heaters
• circulating pump
• control cabinet for heaters and pump
• one set of thermometers

Marine Project Guide W20 - 1/2002 67

 9. Cooling water system

Preheating unit, electric (3V60L0653a)

Heater Pump Weight Pipe conn. Dimensions

capacity capacity
kW m3/h kg In / Outlet A B C D E
7.5 3 75 DN40 1050 720 610 790 425
12 3 93 DN40 1050 550 660 240 450
15 3 93 DN40 1050 720 660 240 450
18 3 95 DN40 1250 900 660 240 450
22.5 8 100 DN40 1050 720 700 290 475
27 8 103 DN40 1250 900 700 290 475
30 8 105 DN40 1050 720 700 290 475
36 8 125 DN40 1250 900 700 290 475
45 8 145 DN40 1250 720 755 350 505
54 8 150 DN40 1250 900 755 350 505

68 Marine Project Guide W20 - 1/2002

 9. Cooling water system

9.3.7. Air venting 9.3.10. Orifices

Air and gas may be entrained in the piping after overhaul, Orifices must be mounted after the HT outlet, after lubri-
centrifugal pump seals may leak, or air or gas may leak from cating oil cooler and in all by-pass lines in order to adjust
in any equipment connected the HT- or LT-circuit, such as the circulations pumps and to balance the pressure drop
diesel engine, water cooled starting air compressor etc. when the water is not flowing through the cooler.
As presented in the external cooling diagrams, it is recom-
mended that air venting equipment is installed in the LT 9.3.11. Waste heat recovery
system line for venting of any entrained air. The waste heat of the HT-circuit may be used for fresh wa-
ter production, central heating, tank heating etc. In such
9.3.8. Local thermometers cases the piping system should permit by-passing of the
Local thermometers should be installed wherever a new central cooler. With this arrangement the HT-water flow
temperature occurs, i.e. before and after each heat through the heat recovery can be increased.
exchanger, etc.

9.3.9. Pressure gauges

Pressure gauges should be installed on the suction and dis-
charge side of each pump.

Marine Project Guide W20 - 1/2002 69

 9. Cooling water system

9.4. Example system diagrams

Cooling water system, auxiliary engines (3V76C5049)

System components Pipe connections

4E05 Preheater 401 HT-water inlet
4E08 Central cooler 402 HT-water outlet
4P04 Preheating pump 404 HT-air vent
4P09 Transfer pump 406 Water from preheater to HT circuit
4S01 Air venting 451 LT-water inlet
4T04 Drain tank 452 LT-water outlet
4T05 Expansion tank 454 LT-water air vent from air cooler

70 Marine Project Guide W20 - 1/2002

 9. Cooling water system

Cooling water system, auxiliary engines and main engine (3V76C5050)

System components Pipe connections

4E05 Preheater 401 HT-water inlet
4E08 Central cooler 402 HT-water outlet
4P04 Preheating pump 404 HT-air vent
4P09 Transfer pump 406 Water from preheater to HT circuit
4P17 LP-pump 451 LT-water inlet
4S01 Air venting 452 LT-water outlet
4T04 Drain tank 454 LT-water air vent from air cooler
4T05 Expansion tank
4V08 Thermostatic valve

Marine Project Guide W20 - 1/2002 71

 9. Cooling water system

Cooling water system, main engine (3V76C5051)

System components Pipe connections

4E05 Preheater 401 HT-water inlet
4E08 Central cooler 402 HT-water outlet
4E10 Gear cooler 404 HT-air vent
4F01 Sea water filter 406 Water from preheater to HT circuit
4P03 HT-stand-by pump 408 HT-water from stand-by pump
4P04 Preheating pump 451 LT-water inlet
4P05 LT-stand-by pump 452 LT-water outlet
4P09 Transfer pump 454 LT-water air vent from air cooler
4P11 Sea-water pump
4S01 Air venting
4T04 Drain tank
4T05 Expansion tank

72 Marine Project Guide W20 - 1/2002

 9. Cooling water system

Cooling water system, HFO engines with evaporator (3V76C5052)

System components Pipe connections

4E05 Preheater 401 HT-water inlet
4E08 Central cooler 402 HT-water outlet
4N02 Evaporator 404 HT-air vent
4P04 Preheating pump 406 Water from preheater to HT circuit
4P09 Transfer pump 451 LT-water inlet
4S01 Air venting 452 LT-water outlet
4T04 Drain tank 454 LT-water air vent from air cooler
4T05 Expansion tank
4V02 Thermostatic valve

Marine Project Guide W20 - 1/2002 73

 9. Cooling water system

Cooling water system, MDO engines with evaporator (3V76C5053)

System components Pipe connections

4E05 Preheater 401 HT-water inlet
4E08 Central cooler 402 HT-water outlet
4N02 Evaporator 404 HT-air vent
4P04 Preheating pump 406 Water from preheater to HT circuit
4P09 Transfer pump 451 LT-water inlet
4S01 Air venting 452 LT-water outlet
4T04 Drain tank 454 LT-water air vent from air cooler
4T05 Expansion tank
4V02 Thermostatic valve
4V03 LT-thermostatic valve

74 Marine Project Guide W20 - 1/2002

 10. Combustion air system

10. Combustion air system

10.1. Engine room ventilation the exits. This is usually done so that the funnel serves as an
exit for the majority of the air. To avoid stagnant air, extrac-
To maintain acceptable operating conditions for the en- tors can be used.
gines and to ensure trouble free operation of all equipment,
It is good practice to provide areas with significant heat
attention shall be paid to the engine room ventilation and
sources, such as separator rooms with their own air supply
the supply of combustion air.
and extractors.
The air intakes to the engine room must be so located that
water spray, rain water, dust and exhaust gases cannot en-
ter the ventilation ducts and the engine room. 10.2. Combustion air quality
The dimensioning of blowers and extractors should en- During normal operating conditions the air temperature at
sure that an overpressure of about 5 mmWC is maintained the turbocharger inlet should be kept between 15ºC and
in the engine room in all running conditions. 35ºC. Temporarily max. 45ºC is allowed.
For the minimum requirements concerning the engine
room ventilation and more details, see applicable stan-
dards, such as ISO 8861. 10.3. Combustion air system
Ventilation
design
The amount of air required for ventilation is calculated Usually, the air required for combustion is taken from the
from the total heat emission F to evacuate. To determine engine room through a filter fitted on the turbocharger.
F, all heat sources shall be considered, e.g.: This reduces the risk for too low temperatures and contam-
ination of the combustion air. It is imperative that the com-
• Main and auxiliary diesel engines
bustion air is free from sea water, dust, fumes, etc.
• Exhaust gas piping The combustion air should be delivered through a dedi-
• Alternators cated duct close to the turbocharger, directed towards the
• Electric appliances and lighting turbocharger air intake. Also auxiliary engines shall be
served by dedicated combustion air ducts.
• Boilers
For the required amount of combustion air, see the chap-
• Steam and condensate piping ter for Technical data.
• Tanks If necessary, the combustion air duct can be directly con-
It is recommended to consider an outside air temperature nected to the turbocharger with a flexible connection
of not less than 35°C and a temperature rise of 11°C for the piece. To protect the turbocharger a filter must be built into
ventilation air. the air duct. The permissible pressure drop in the duct is
The amount of air required for ventilation is then calcu- max. 100 mmWC.
lated from the formula:
Charge air shut-off valve
F In installations where it is possible that the combustion air
Qv = includes combustible gas or vapour the engines can be
r · Dt · c
equipped with charge air shut-off valve. This is also regu-
where: lated in the classification rules for Offshore Units as man-
datory.
Qv = amount of ventilation air [m³/s]
F = total heat emission to be evacuated [kW] 10.3.1. Cold operating conditions
r = density of ventilation air 1.15 kg/m³
In installations intended for operation in cold air condi-
Dt = temperature rise in the engine room [°C] tions, restrictions for operation at low air temperature must
c = specific heat capacity of the ventilation air 1.01 be considered. See Chapter for Operation ranges for de-
kJ/kgK tails.
The heat emitted by the engine is listed in the chapter for Combustion air for engines
Technical data.
The ventilation air is to be equally distributed in the engine • Each engine has its own combustion air fan, with a ca-
room considering air flows from points of delivery towards pacity slightly higher than the maximum air consump-

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 10. Combustion air system

tion. The fan should have a two-speed electric motor (or Engine room ventilation
variable speed) for enhanced flexibility. In addition to
• The rest of the engine room ventilation is provided by
manual control, the fan speed can be controlled by the
separate ventilation fans. These fans should preferably
engine load.
have two-speed electric motors (or variable speed) for
• The combustion air is conducted close to the enhanced flexibility.
turbocharger, the outlet being equipped with a flap for
• For very cold conditions a preheater in the system
controlling the direction and amount of air.
should be considered. Suitable media could be thermal
With these arrangements the normally required minimum oil or water/glycol to avoid the risk for freezing. If steam
air temperature to the main engine, see Chapter for opera- is specified as a heating system for the ship the preheater
tion ranges, can typically be maintained. For lower temper- should be in a secondary circuit.
atures special provisions are necessary.
• This system permits flexible operation, e.g. in port the
In special cases the duct can be connected directly to the capacity can be reduced during overhaul of the main en-
turbocharger, with a stepless change-over flap to take the gine when it is not preheated (and therefore not heating
air from the engine room or from outside depending on en- the room).
gine load.

Engine room ventilation (4V69E8169)

1 Diesel engine
2 Suction louver *
3 Water trap
4 Combustion air fan
5 Engine room ventilation fan
5 Flap
6 Outlets with flaps
* Recommended to be equipped with a filter for ar-
eas with dirty air (rivers, coastal areas, etc.)
Ambient air temperature

Condensation in charge air coolers

Example, according to the diagram:
At an ambient air temperature of 35°C and a relative hu-
midity of 80%, the content of water in the air is 0.029 kg
water/ kg dry air. If the air manifold pressure (receiver
pressure) under these conditions is 2.5 bar (= 3.5 bar abso-
Water dewpoint

lute), the dew point will be 55°C. If the air temperature in

the air manifold is only 45°C, the air can only contain 0.018
kg/kg. The difference, 0.011 kg/kg (0.029 - 0.018) will ap-
pear as condensed water.

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 11. Exhaust gas system

11. Exhaust gas system

11.1. Internal exhaust gas system mounts are acceptable at the fixing points between the
exhaust pipe and the rigid support. The mounts must how-
11.1.1. Exhaust gas outlet ever be stiff enough to prevent dynamic deflections in ex-
cess of 1 mm peak to peak. Conical rubber mounts similar
Exhaust gas outlet (4V76A2679)
to the mounts that are installed under generating sets can
be used. Adequate thermal insulation must be provided to
protect the rubber mounts from high exhaust gas tempera-
tures.
The piping should be as short and straight as possible.
The bends should be made with the largest possible bend-
ing radius, minimum radius used should be 1.5 D. The ex-
haust pipe must be insulated all the way from the
turbocharger and the insulation is to be protected by a cov-
ering plate or similar to keep the insulation intact. Closest
to the turbocharger the insulation should consist of a hook
on padding to facilitate maintenance. It is especially impor-
tant to prevent the airstream to the turbocharger detaching
insulation, which will then clog the filters.
The exhaust gas pipes and/or silencers should be provided
with water separating pockets and drainage.
Recommended flow velocity is 35...40 m/s. Lower veloci-
ties might be needed with long piping or if there are many
resistance factors in the piping.
The exhaust gas mass flow given in the Chapter for Tech-
nical data can be translated to velocity using the formula:
Bellows A Piping B
Engine 4·m
(inner dia) (inner dia) v [m/s] = ——————
273
4L20 200 250-300 ( 273 + t
)
1.3 · —————— · p · D²

5L20 250 300-350

Where:
6L20 250 300-350
v[m/s] = gas velocity
8, 9L20 300 350-450
m [kg/s] = exhaust gas mass flow
t [°C] = exhaust gas temperature
The exhaust gas outlet from the turbocharger can be in-
clined to several positions, the positions depending on the D [m] = exhaust gas pipe diameter
number of cylinders, from the vertical. Other directions
can be arranged by means of the adapter at the 11.2.1. Silencer (5R01)
turbocharger outlet. When included in the scope of supply, the standard si-
lencer is of the absorption type, equipped with a spark ar-
11.2. External exhaust gas rester. It is also provided with a soot collector and a water
drain, but is without mounting brackets and insulation. The
system silencer can be mounted either horizontally or vertically.
Each engine should have its own exhaust pipe into open The noise attenuation of the standard silencer is either 25
air. Flexible bellows have to be mounted directly to the or 35 dB(A).
turbocharger outlet, to compensate for thermal expansion
and prevent damages on the turbocharger due to vibra-
tions.
It is very important that the exhaust pipe is properly fixed
to a rigid support directly after the bellows. Resilient

Marine Project Guide W20 - 1/2002 77

 11. Exhaust gas system

Exhaust silencer (4V49E0137a)

Attenuation
25 dB (A) 35 dB (A)
DN D A B L Weight (kg) L Weight (kg)
250 700 335 120 2070 230 2870 340
300 700 395 150 2600 280 3600 400
350 850 445 180 2640 340 3640 490
400 950 495 205 3180 500 4180 670
450 1100 550 230 3440 600 4440 780

11.2.2.Exhaust gas boiler 11.2.4.Supporting

If exhaust gas boilers are installed, each engine should have The number of mounting supports should always be kept
a separate exhaust gas boiler. Alternatively, a common to a minimum and positioned at stiffened locations within
boiler with separate gas sections for each engine is accept- the ship’s structure, e.g. decklevels, framewebs or specially
able. constructed supports.
For dimensioning the boiler, the exhaust gas quantities and The supporting must allow thermal expansion and ship’s
temperatures given in the Chapter for Technical data may structural deflections during construction and operation.
be used.
11.2.5.Back pressure
11.2.3.Bellows (5H01)
The maximum permissible exhaust gas back pressure is 3
Bellows must be used in exhaust gas piping where thermal kPa at full load, which should be verified by a calculation,
expansion or ship’s structural deflections have to be segre- made by the shipyard. The back pressure should also be
gated in order to limit stress levels. measured on the sea trial. A measuring connection should
be provided on each exhaust piping system during the con-
struction.

78 Marine Project Guide W20 - 1/2002

 12. Turbocharger and air cooler cleaning

12. Turbocharger and air cooler cleaning

12.1. Turbine cleaning system The water flow required for each turbine washing depends
(5Z03) on the final turbocharger selection. The following typical
values can be given (for guidance) for engines with a nomi-
Periodic water cleaning of the turbine reduces the forma- nal speed of 900 or 1000 rpm:
tion of deposits and extends the interval between over- • 4L20: 6 l/min
hauls. Only fresh water should be used and the cleaning
instructions in the operation manual must be carefully fol- • 5L20, 6L20: 8 l/min
lowed. • 8L20, 9L20: 10 l/min
For washing of the turbine side of the turbocharger, fresh The washing time is three times 30 seconds with 10 min-
water with a pressure of not less than 300 kPa (3.0 bar) is re- utes between washings.
quired.
The washing is carried out during operation at regular in-
tervals, depending on the quality of the heavy fuel, 100 –
500 h.
Turbocharger cleaning system (4V76A2709)

System components Pipe connections

01 Shut of and flow adjusting unit, bulkhead mounted 502 Cleaning water to turbine
02 Rubber hose about 10 m Quick coupling

Marine Project Guide W20 - 1/2002 79

 13. Exhaust emissions

13. Exhaust emissions

13.1.General 13.2.2.Sulphur Oxides (SOx)
Exhaust emissions from the diesel engine mainly consist of Sulphur oxides (SOx) are direct result of the sulphur con-
nitrogen, carbon dioxide (CO2) and water vapour with tent of the fuel oil. During the combustion process the fuel
smaller quantities of carbon monoxide (CO), sulphur ox- bound sulphur is rapidly oxidised to sulphur dioxide
ides (SOx) and nitrogen oxides (NOx), partially reacted (SO2). A small fraction of SO2 may be further oxidised to
and non-combusted hydrocarbons and particulates. Emis- sulphur trioxide (SO3). The SOx emission controls are di-
sion control of large diesel engines means primarily the rected mainly at limiting the sulphur content of the fuel.
control of the NOx emissions.
To improve the combustion process and reduce the emis- 13.2.3.Particulates
sions, especially NOx emissions, Wärtsilä has developed a The particulate fraction of the exhaust emissions repre-
Low NOx combustion process that substantially reduces sents a complex mixture of inorganic and organic sub-
the NOx level without compromising thermal efficiency. stances mainly comprising soot (elemental carbon), fuel oil
The Low NOx combustion concept has been imple- ash (together with sulphates and associated water), ni-
mented in all Wärtsilä engines. trates, carbonates and a variety of non or partially
combusted hydrocarbon components of the fuel and lubri-
13.2.Diesel engine exhaust cating oil.
The main parameters affecting the particulate emissions
components are the fuel oil injection and fuel oil parameters. The use of
Due to the high efficiency of the diesel engines, the emis- fuel oil with good ignition and combustion properties and
sions of carbon dioxide (CO2), carbon monoxide (CO) low content of ash and sulphur will reduce the formation
and hydrocarbons (HC) are low. The same high combus- of particulates. For marine diesel engines the particulate re-
tion temperatures that give thermal efficiency in the diesel moval systems, because of their size and high cost, are not
engine also cause high emissions of nitrogen oxides (NOx). for the time being economically or practically potential so-
The emissions of sulphur oxides (SOx) and particulates are lutions.
formed in the combustion process out of the sulphur, ash
and asphaltenes that are always present in heavy fuel oil. 13.2.4.Smoke
Although smoke is usually the visible indication of
13.2.1.Nitrogen oxides (NOx) particulates in the exhaust, the correlations between par-
Nitric oxide (NO) and Nitrogen dioxide (NO2) are usually ticulate emissions and smoke is not fixed. The lighter and
grouped together as NOx emissions. Predominant oxide more volatile hydrocarbons will not be visible nor will the
of nitrogen found inside the diesel engine cylinder is NO, particulates emitted from a well maintained and operated
which forms mainly in the oxidation of atmospheric (mo- diesel engine.
lecular) nitrogen in the high temperature gas regions. NO Smoke can be black, blue, white, yellow or brown in ap-
can also be formed through oxidation of the nitrogen in pearance. Black smoke is mainly comprised of carbon
fuel and through chemical reactions with fuel radicals. The particulates (soot). Blue smoke indicates the presence of
amount of NO2 emissions is approximately 10-30 %. the products of the incomplete combustion of the fuel or
All standard Wärtsilä engines meet the NOx emission level lubricating oil. White smoke is usually condensed water
set by the IMO (International Maritime Organisation) and vapour. Yellow smoke is caused by NOx emissions. When
most of the local emission levels without any modifica- the exhaust gas is cooled significantly prior to discharge to
tions. Wärtsilä has also developed solutions to significantly the atmosphere, the condensed NO2 component can have
reduce NOx emissions when it is required. For Wärtsilä 20, a brown appearance.
the Selective Catalytic Reduction (SCR) is an optional NOx
reduction method.

80 Marine Project Guide W20 - 1/2002

 13. Exhaust emissions

13.3. Marine exhaust emissions The IMO NOx limit is defined as follows:

legislation NOx [g/kWh]

= 17 rpm < 130
The increasing concern over the air pollution has resulted = 45 x rpm-0.2 130 < rpm < 2000
in the introduction of exhaust emission controls to the ma-
rine industry. To avoid the growth of uncoordinated regu- = 9.8 rpm > 2000
lations, the IMO (International Maritime Organisation) IMO NOx emission limit
has developed the Annex VI of MARPOL 73/78, which
represents the first set of regulations on the marine exhaust
emissions.
18
There is yet no legislation concerning the particulate emis- 17
sions from the marine diesel engines, although the authori- 16

NOx, weigh ted (g/kWh)

15
ties are planning to set strict limits to the particulates in the 14
near future. Smoke is regulated in some countries or re- 13
gions based on its visibility. 12
11
10
13.3.1. MARPOL Annex VI 9
8
MARPOL 73/78 Annex VI includes regulations for exam- 0 500 1000 1500 2000
Rated engine speed (rpm)
ple on such emissions as nitrogen oxides, sulphur oxides,
volatile organic compounds and ozone depleting sub-
stances. The Annex VI has yet to be ratified. The regula-
tions will enter into force 12 months after the date on 13.3.2. EIAPP Statement of Compliance
which at least 15 states, constituting not less than 50 % of An EIAPP (Engine International Air Pollution Preven-
the gross tonnage of the world’s merchant shipping, have tion) Statement of Compliance will be issued for each en-
signed the protocol. The most important regulation of the gine showing that the engine complies with the NOx
MARPOL Annex VI is the control of NOx emissions. regulations set by the IMO. For the time being only a State-
All Wärtsilä engines are Low NOx engines and comply ment of Compliance can be issued, because the regulation
with the proposed NOx levels set by the IMO in the is not yet in force.
MARPOL Annex VI. The NOx controls apply only to die- When testing the engine for NOx emissions, the reference
sel engines over 130 kW installed on ships built (defined as fuel is Marine Diesel Fuel (distillate) and the test is per-
date of keel laying or similar stage of construction) on or af- formed according to ISO 8178 test cycles. Subsequently,
ter January 1, 2000 along with engines which have under- the NOx value has to be calculated using different weight-
gone a major conversion on or after January 1, 2000. ing factors for different loads that have been corrected to.
For Wärtsilä 20 with a rated speed of 720 rpm, the NOx ISO 8178 conditions. The most commonly used ISO 8178
level is below 12.1 g/kWh and with 750 rpm the level is be- test cycles are presented in following table.
low 12.0 g/kWh. With a rated speed of 900 rpm the NOx
level is below 11.5 g/kWh and with 1000 rpm the level is
below 11.3 g/kWh. The tests are done according to IMO
regulations (NOx Technical Code).
Table 13.1. ISO 8178 test cycles.

E2: Diesel electric propulsion, Speed (%) 100 100 100 100
variable pitch Power (%) 100 75 50 25
Weighting factor 0.2 0.5 0.15 0.15
E3: Propeller law Speed (%) 100 91 80 63
Power (%) 100 75 50 25
Weighting factor 0.2 0.5 0.15 0.15
D2: Auxiliary engine Speed (%) 100 100 100 100 100
Power (%) 100 50 50 25 10
Weighting factor 0.05 0.3 0.3 0.3 0.1

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 13. Exhaust emissions

For EIAPP certification, the “engine family” or the “en- 13.4.1.Selective Catalytic Reduction (SCR)
gine group” concepts may be applied. This has been done
Selective Catalytic Reduction (SCR) is the only way to
for the Wärtsilä 20 diesel engine. The engine families are
represented by their parent engines and the certification reach a NOx reduction level of 85-95%.
emission testing is only necessary for these parent engines. General system description
Further engines can be certified by checking documents,
The reducing agent, aqueous solution of urea (40 wt-%), is
components, settings etc., which have to show correspon-
injected into the exhaust gas directly after the
dence with those of the parent engine.
turbocharger. Urea decays immediately to ammonia
All non-standard engines, for instance over-rated engines, (NH3) and carbon dioxide. The mixture is passed through
non-standard-speed engines etc. have to be certified indi- the catalyst where NOx is converted to harmless nitrogen
vidually, i.e. “engine family” or “engine group” concepts and water, which are normally found in the air that we
do not apply. breathe. The catalyst elements are of honeycomb type and
According to the IMO regulations, a Technical File shall are typically of a ceramic structure with the active catalytic
be made for each engine. This Technical File contains in- material spread over the catalyst surface.
formation about the components affecting NOx emis- The injection of urea is controlled by feedback from a
sions, and each critical component is marked with a special NOx measuring device after the catalyst. The rate of NOx
IMO number. Such critical components are injection noz- reduction depends on the amount of urea added, which
zle, injection pump, camshaft, cylinder head, piston, con- can be expressed as NH3/NOx ratio. The increase of the
necting rod, charge air cooler and turbocharger. The catalyst volume can also increase the reduction rate.
allowable setting values and parameters for running the en-
When operating on HFO, the exhaust gas temperature be-
gine are also specified in the Technical File.
fore the SCR must be at least 330°C, depending on the sul-
The marked components can later, on-board the ship, be phur content of the fuel. When operating on MDF, the
easily identified by the surveyor and thus an IAPP (Interna- exhaust gas temperature can be lower. If an exhaust gas
tional Air Pollution Prevention) Statement of Compliance boiler is specified, it should be installed after the SCR.
for the ship can be issued on basis of the EIAPP Statement
of Compliance and the on-board inspection.

13.4.Methods to reduce exhaust

emissions
Diesel engine exhaust emissions can be reduced either
with primary or secondary methods. The primary methods
limit the formation of specific emissions during the com-
bustion process. The secondary methods reduce emission
components after formation as they pass through the ex-
haust gas system.

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 13. Exhaust emissions

Typical P&ID for Compact SCR (3V28A0006a)

The disadvantages of the SCR are the large size and the rel- Urea consumption and replacement of catalyst layers are
atively high installation and operation costs. To reduce the generating the main running costs of the catalyst. The urea
size, Wärtsilä has together with subsuppliers developed the consumption is about 15-20 g/kWh of 40 wt-% urea. The
Compact SCR, which is a combined silencer and SCR. The urea solution can be prepared mixing urea granulates with
Compact SCR will require only a little more space than an water or the urea can be purchased as a 40 wt-% solution.
ordinary silencer. The urea tank should be big enough for the ship to achieve
The lifetime of the catalyst is mainly dependent on the fuel relative autonomy.
oil quality and also to some extent on the lubricating oil
quality. The lifetime of a catalyst is typically 3-5 years for
liquid fuels and slightly longer if the engine is operating on
gas. The total catalyst volume is usually divided into three
layers of catalyst, and thus one layer at time can be replaced,
and remaining activity in the older layers can be utilised.

Marine Project Guide W20 - 1/2002 83

 14. Automation system

14. Automation system

14.1.General • Stop signal to engine activated (safety shut-down, emer-
gency stop, normal stop)
Engine automation system consists of local and remote
control of the running parameters, local and remote moni- • Stop lever on stop position
toring of the sensors and automatic safety operations. In an emergency case, the engine can always be started by
manually operating the main starting valve. This by-passes
start blocking due to low prelubricating pressure.
14.2.Power supply
Starting air cut off
Automation system requires depending on the scope 24
The start signal to be cut off by:
VDC about 150 W.
• Speed switch in SPEMOS (115 RPM)
• A time relay function, which allows the start signal to be
14.3.Safety System activated about 5 seconds. The time between consecu-
tive starting attempts shall be about 30 seconds.
14.3.1.General
• Stop signal to engine activated.
The safety system can be split into five major parts: start-
ing, stopping, start blocking, shutdowns and load reduc- Start fuel limiter
tion requests. The speed governor is provided with a start fuel limiter
function in order to optimize the fuel injection during the
14.3.2.Starting (8N08) acceleration period. This is controlled by a speed switch in
the speed measuring system.
Start of an auxiliary engine
Override of lubricating oil pressure shut-down
The principle diagram of a start/stop system is shown in
drawing 4V50G3472. To enable start of the engine, the automatic shut-down for
low lubricating oil pressure must be disabled during the
The described relay automation is usually not included in
starting sequence. This is most conveniently done using
the scope of supply, but can as an option be supplied in a
the “engine running” contact. Further, a time delay of
separate cabinet. The control, safety and sequencing func-
about 10 seconds is to be arranged in order to allow the en-
tions of this system can also be incorporated in the power
gine driven lubricating oil pump to establish sufficient
management or automation system of the vessel.
pressure.
Start sequence
Start of a main engine
The engine is equipped with a pneumatic starting motor,
which drives the engine through a gear rim on the flywheel. The principle diagram of a start/stop system is shown in
The starting motor is controlled by a solenoid valve. The drawing 4V50G3619.
engine can be started by activating the solenoid valve, lo- A main engine can be started and stopped in the same way
cally by a start button on the engine or remotely e.g. from as an auxiliary engine. Some minor differences should,
the diesel automation system. however, be noted:
A generating set reaches the nominal speed in 6...8 seconds • The 5 min. time delay of prelubricating pressure de-
after the starting solenoid has been activated. scribed for black-out start is not recommended.
Start blocking (8N08) • For some installations start blocking may be required
from clutch position, pitch NOT zero and reduction
Starting shall be inhibited by the following functions:
gear lubricating oil pressure. Autostop of the engine can
• Turning device engaged also be required for low lubricating oil pressure in the re-
• Prelubricating pressure low. In case of black-out, start- duction gear.
ing is allowed within 5 minutes after the pressure has
dropped below the set point of 0.5 bar.
• Engine start blocking selector switch turned into
“Blocked” position
• Engine running (300 rpm)

84 Marine Project Guide W20 - 1/2002

 14. Automation system

14.3.3. Stopping (8N08) The shutdown is latching, and a shutdown reset has to be
given before it is possible to re-start. Naturally, before this
Normal stop of the engine the reason of the shutdown must be investigated.
The engine is stopped remotely via the ‘remote stop’ input For a single main engine installation it might be necessary
or in local control by the stop button on the engine. to arrange a 5 sec delay on the autostop functions (except
Manual stop can also be done by turning the stop lever into for overspeed) to give the possibility of overriding the
the stop position. autostop signal from the bridge and prevent the engine
There are two stop solenoids on the engine. One is built from stopping in a critical manoeuvring situation.
into the speed governor. The other one is controlling com- Overspeed protection
pressed air, which is fed to pneumatic cylinders at each fuel
injection pump, forcing the pumps to no-fuel when acti- A main engine is equipped with two independently adjust-
vated. This system is independent of the governor. The en- able switches for overspeed.
gine can be stopped by activating one or both of the • The speed switch with the lower set point (nom. RPM +
solenoids for at least 60 seconds. Emergency and safety 15%) can be connected for momentary activation of the
shut-down should activate both. electro-pneumatic stop solenoid. The speed switch is ac-
When two engines are connected to a common reduction tivated and the stop solenoid is energized only as long as
gear it is recommended that the clutches are blocked in the the speed is above the set point. When the speed has de-
“OUT” position when the engine is not running. When an creased, the stop solenoid is de-energized and the speed
engine is stopped, the clutch should open to prevent the is again controlled by the governor.
engine from being driven through the gear. At an The speed switch with the higher set point (nom. RPM +
overspeed shutdown signal the clutch should remain 18%) shall be connected with latching function in order to
closed. ensure shut-down of the engine.
‘Engine stop/shutdown output’ is always closed when the
stop signal is active. 14.3.5. Charge air shut-off valve
For a single main engine installation it might be necessary If gas detector senses combustible gas or vapour in the en-
to arrange a 5 sec delay on the autostop functions (except gine room the charge air shut-off valve must be automati-
for overspeed) to give the possibility of overriding the cally closed and engine shutdown activated. Also
autostop signal from the bridge and prevent the engine overspeed of the engine should automatically close this
from stopping in a critical manoeuvring situation. valve and activate shutdown. Since this is optional equip-
ment most commonly used in offshore installations the
14.3.4. Shutdowns (8N08) construction varies with engine type and installation and
the instructions in manuals must be followed.
The engine shall be automatically shut down in the follow-
ing cases:
• Lubricating oil pressure low (pressure switch) 14.4. Speed Measuring (8N03)
• Cooling water temperature high (temperature switch) An electronic speed measuring and monitoring system
• Overspeed (speed switch in SPEMOS) (SPEMOS) is built into the engine junction box.
The system monitors the engine speed with two pick-ups
and the turbocharger speed with a single pick-up. A 24 V
DC power supply is required for the SPEMOS.

Table 14.1. Speed measuring & monitoring system signals

Function Signal Usage Remark

Start fuel limiter contact internal 100 RPM below idling speed
Starting air cut off contact internal 115 RPM
Engine running volt. free contact external 300 RPM
Overspeed volt. free contact external nominal + 15% speed
Engine speed 0 - 10 V DC internal & external 0 - 1500 RPM
Turbocharger speed 0 - 10 V DC internal & external 0 - 60000 RPM
Power/tacho failure volt. free contact external

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 14. Automation system

14.5.Sensors & signals

Drawing 4V50L5692 shows a typical engine wiring dia-
gram with a standard set of sensors for monitoring, alarm
and safety.
Table 14.2. Standard sensors for remote monitoring and alarm

Sensor Code Signal Alarm Remark

Fuel oil pressure PT101 4 - 20 mA 0.4 MPa (4 bar) HFO
Lubricating oil pressure PT201 4 - 20 mA 0.3 MPa (3 bar)
Starting air pressure PT301 4 - 20 mA 0.8 MPa (8 bar)
HT water pressure PT401 4 - 20 mA 0.2 MPa (2 bar) installation specific
LT water pressure PT451 4 - 20 mA 0.2 MPa (2 bar) installation specific
Exhaust gas temperature after each
TE501 4 - 20 mA 500°C NiCrNi + amplifier
cylinder and turbocharger
Lubricating oil temperature TE201 Pt 100 80°C
HT water temperature TE402 Pt 100 105°C
Charge air temperature TE622 Pt 100 75°C
Injection pipe leakage LS103A volt. free contact —
Lubricating oil level in wet oil sump low LS204 volt. free contact —
Lubricating oil filter pressure drop PDS243 volt. free contact 0.15 MPa (1.5 bar)
Pneumatic overspeed trip pressure low PS311 volt. free contact 1.8 MPa (18 bar)
Overload GS166 volt. free contact — main engines only

86 Marine Project Guide W20 - 1/2002

 14. Automation system

Marine Project Guide W20 - 1/2002 87

 14. Automation system

14.6.Local instrumentation Stop of the standby pump should always be a manual oper-
ation. Before stopping the standby pump, the reason for
The engine is equipped with the following set of instru- the pressure drop must have been investigated and recti-
ments for local reading of pressures, temperatures and fied.
other parameters. Monitoring signals can be used to initiate the start of
Pressure gauges in panel on engine stand-by pumps.

• Lubricating oil pressure 14.7.2.Pre-lubricating oil pump (9N03)

• Fuel oil pressure
The engine is equipped with an electric pre-lubricating
• Cooling water pressure (HT) pump.
• Cooling water pressure (LT) The pre-lubricating pump is used for filling of the lubricat-
• Charge air pressure ing oil system, pre-lubricate a stopped engine before start
and for preheating by circulating warm lubricating oil. The
• Starting air pressure
colder the engine is, the earlier the pump should be started
Thermometers before the engine is started.
• Fuel oil before engine The pump may also be run continuously when the engine
is stopped and must run in multiple engine installations
• Lubricating oil before lubricating oil cooler when other engines are running.
• Lubricating oil after lubricating oil cooler For continuous prelubrication of a stopped engine,
• Cooling water (HT) before engine through which heavy fuel is circulating.
• Cooling water (HT) after engine To ensure continuous prelubrication of a stopped engine,
• Cooling water (LT) before charge air cooler automatic starting and stopping of the prelubricating
pump is recommended. This can be achieved using the 300
• Cooling water (LT) after charge air cooler RPM speed switch.
• Cooling water (LT) after lubricating oil cooler For dimensioning the pre-lubricating pump starter, the
• Charge air after charge air cooler values indicated below can be used. For different voltages,
the values may differ slightly. The starter is not included in
Electrical instruments the standard delivery of the engine.
• Tachometer for engine speed and turbocharger speed • 400V / 50Hz 2.2kW, In=4.7A
• Running hour counter • 440V / 60Hz 2.5kW In=4.7A
• Digital display for exhaust gas temperature with selector
switch for temperature after each cylinder and after 14.7.3.Cooling water pre-heater &
turbocharger circulation pump
In order to get the engine up to and maintain a cooling wa-
14.7.Control of auxiliary ter temperature >70°C, preheating has to be arranged for
equipment the engine. Preheating is preferably done by an Electric
preheater with a required heating power depending of the
14.7.1.Stand-by pumps engine type. The preheater is not included in the standard
delivery of the engine.
Stand-by pumps are required for single main engine. The temperature control should be automatic.
If the pressure drops below a pre-set level when the engine For automatic starting and stopping of the circulating
is running, the stand-by pump should be started. The pump to circulate cooling water through the stopped en-
stand-by pump starter shall include an interposing relay gine(s), the ‘Engine running’ signal can be used as refer-
controlling the main contactor. ence.
Latching must be done in the standby starter and alarm In some main engine installations the circulating pump
system respectively. The reason for the pressure drop needs to be running at prolonged idling. For these cases
should be investigated as soon as possible. special instructions are given.

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14.8. Speed control (8I03) nals. This is often required in order to achieve good stabil-
ity without sacrificing the transient response. Further the
14.8.1. Main engine speed control dynamic response can easily be adjusted and optimised for
the particular installation, or even for different operating
Mechanical-hydraulic governors modes of the same engine. An electronic speed control is
The engines have hydraulic-mechanical governors with also capable of isochronous load sharing. In isochronous
pneumatic speed setting. These governors are usually pro- mode, there is no need for external load sharing, frequency
vided with a shut-down solenoid as the only electrical adjustment, or engine loading/unloading control in the ex-
equipment. ternal control system. Both isochronous load sharing and
traditional speed droop are standard features in all elec-
The idling speed is selected for each installation based on tronic speed controllers and either mode can be easily se-
calculations, for CP-propeller installations at 60 - 70% of lected.
the nominal speed and for FP-propeller installations at
about 35%. Speed droop means that the governor speed reference au-
tomatically decreases as the engine load increases. The
The standard control air pressure for pneumatically con- speed droop is normally adjusted to about 4%. This is to
trolled governors is: ensure proper load sharing between parallelling units. To
p = 0.514 * n - 14.3 compensate for the speed decrease of the plant when the
p = control air pressure [kPa] load increases, and vice versa when the load decreases, the
n = engine speed [RPM] PMS must in an outer (cascade) loop correct for the fre-
quency drift.
Governors for engines in FP-propeller installations are
provided with a smoke limiting function, which limits the Isochronous load sharing means that the governor speed
fuel injection as a function of the charge air pressure. reference stays the same, regardless of the load level. A
shielded twisted pair cable between the speed controllers is
Governors are, as standard, equipped with a built-in delay
necessary for isochronous load sharing. If the ship has two
of the speed change rate so that the time for speed accelera-
or more switchboard sections, which can be either con-
tion from idle to rated speed and vice versa is preset.
nected or separated, there must be a breaker also for the
In special cases speed governors of the electronic type can load sharing lines between each speed control.
be used.
Electronic speed control for Main Engines
14.8.2. Generating set speed control An electronic speed control is recommended for more de-
manding installations, e.g. main engine installations with
Mechanical-hydraulic governors
two engines connected to the same reduction gear, in par-
Auxiliary generator sets are normally provided with me- ticular if there is a shaft generator on the reduction gear.
chanical-hydraulic governors for remote electric speed set- The remote speed setting can be either an increase/de-
ting from e.g. a Power Management System (PMS). crease signal, or an analog 4-20mA speed reference, both
The governor is equipped with a speed setting motor for from e.g. a PCS. The rate at which the speed changes is ad-
synchronizing, load sharing and frequency control. justable in the speed controller.
The governor is also equipped with a shutdown solenoid Actuators with mechanical backup are only recommended
and an electrically controlled start fuel limiter. The syn- for single main engines. The actuator should in case of a
chronizing is operated by ON/OFF control as “increase” single main engine be reverse acting, so that the change
or “decrease” by polarity switching. Normal speed change over to the mechanical backup takes place automatically.
rate is about 0.3 Hz/s.
Electronic speed control for Diesel
Engines, which are to be run in parallel have governors
specially adapted for the same speed droop, about 4%, to
electric/Generator set
obtain basic load sharing. During load sharing and fre- An electronic speed control is always recommended for
quency control, the external load sharing system (PMS) diesel electric installations due to the sometimes strongly
must have a control deadband implemented, allowing for fluctuating power demand from the dominant consumer
an uneven load or frequency drift of 1 - 2%. (propulsion).
For an auxiliary generating set, an electronic speed control
14.8.3. Electronic speed governor can be specified as an option.
An Electronic speed control, comprising a separately Actuators with mechanical backup are not recommended
mounted electronic speed control unit and a built-on actu- for multi-engine installations.
ator, offers efficient tools for filtering speed and load sig-

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 14. Automation system

14.9.Microprocessor based 14.9.2.Functions of the MCU

engine control system The MCU collects measuring data from the sensors on the
(WECS) (8N01) engine, converts the information into digital form and
communicates by serial link with the external monitoring,
As an alternative to the conventional way of cabling the alarm and control systems. The MCU also handles the
sensor signals wire by wire from the engine to the external functions described in the previous paragraphs, i.e. speed
alarm, monitoring and control systems, an Engine Control measuring, start/stop sequences and automatic
System (WECS) can be provided. The WECS is a micro- shut-downs. Vital functions, such as lubricating oil pres-
processor based monitoring and control system. sure and overspeed shut-down, are also handled by exter-
nal switches independent of the MCU.
14.9.1.Components
14.9.3.Communications
The system for one engine consists of one main control
unit (MCU) and several distributed control units (DCU) or By having field bus connection via multi-standard
sensor multiplexer units (SMU) depending on the amount RS-ports for communication with external systems, ca-
of sensors which are connected to the DCU:s and SMU:s. bling work furnished by the yard will be minimized. In ad-
The SMU is used only to collect sensor data, while the dition, installation work, service and maintenance will be
DCU also is used for distributing processing power from easier.
the MCU. The RS-interface is 4-wire RS485. The communication
follows the Modbus RTU protocol specifications with the
MCU as a slave in the Modbus network. A typical setup is a
monitoring and alarm system functioning as a master and
each MCU (one per engine) functioning as slaves.

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Typical wiring diagram (4V50L5692-1a)

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Typical wiring diagram (4V50L5692-2a)

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Typical wiring diagram (4V50L5692-3a)

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 14. Automation system

Typical wiring diagram (4V50L5692-4a)

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Typical wiring diagram (4V50L5692-5a)

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 14. Automation system

Start stop system for an auxiliary engine (4V50G3472-1d)

Indication lamps Pushbuttons and selectors

H1 Power on S1 Emergency stop
H2 Ready for start S2 Stop
H3 Engine running S3 Start
H4 Cooling water temperature high S4 Reset
H5 Lubrication oil pressure low S5 Lamp test
H6 Overspeed S6 Local / Remote mode of start
H7 Start failure

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Start stop system for an auxiliary engine (4V50G3472-2d)

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Start stop system for an auxiliary engine (4V50G3472-3d)

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Start stop system for an auxiliary engine (4V50G3472-4d)

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 14. Automation system

Start/stop system for a main engine (4V50G3619-1a)

Indication lamps Pushbuttons and selectors

H1 Power on S1 Emergency stop
H2 Ready for start S2 Stop
H3 Engine running S3 Start
H4 Overload S4 Reset
H5 Cooling water temperature high S5 Lamp test
H6 Lubrication oil pressure low S6 Local / Remote mode of start
H7 Overspeed
H8 Reduction gear lubrication pressure low
H9 Start failure

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Start/stop system for a main engine (4V50G3619-2a)

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Start/stop system for a main engine (4V50G3619-3a)

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Start/stop system for a main engine (4V50G3619-4a)

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 14. Automation system

Start/stop system for a main engine (4V50G3619-5a)

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 15. Electrical power generation and management

15. Electrical power generation and manage-

ment
15.1. General 15.1.2. Electric load demand at consumers
and generators
The electrical concept design, either performed by the
Ship Owner, Consultant, Yard or Wärtsilä as ‘The Ship The load demand analysis (electric load balance) listing the
Power Supplier’, is the basis for a co-ordination and opti- various loads and modes onboard ship is usually evaluated
misation of the electric power generation and management in the concept design phase and made available to the gen-
being supplemented by these general guidelines. erator set supplier as the basis for dimensioning the genera-
tor sets.
15.1.1. Definitions The generator feeds power to the consumers in the net-
work including all electrical transmission losses. If only the
The marine vessel’s electric supply system is basically an al-
consumer power consumption is advised, the total re-
ternating current (a.c.) three-phase, three–wire insulated.
quired power supplied by the generator shall be increased
The engine produced mechanical energy is converted into
with the network losses, which typically could be 5…9 %
electrical energy by a generator, which usually is of the syn-
chronous type and intended for continuous operation. depending on type, size and quality of electrical compo-
nents.
The voltage of the network and generator is low voltage
(LV) up to 1000 V and medium voltage (MV) from 1 kV. 15.1.3. Operation modes
Ordinary low voltages are 400 V (50 Hz), 450 V (60 Hz)
and 690 V (50 or 60 Hz). The generators shall be capable of operating in parallel.
Nominal medium system voltages are 3 kV, 3,3 kV, 6 kV, The operation modes of the vessel have different demands
6,6 kV, 10 kV and 11 kV for 50 Hz or 60 Hz. of electric power and number of generating sets in opera-
tion. Important factors are among others (illustrated by ex-
Low voltage is normally used in installations with total
amples):
power up to about 10 MVA due to short circuit current re-
strictions in the switchgear. • operation profile
The common network frequency (f) is 50 Hz or 60 Hz and • actual operation mode and maximum expected load
the generator synchronous rated speed nrG [rpm] is calcu- • operational practice (e.g. at least 2 generating sets run-
lated from: ning)
nrG = 60 * f/p • redundancy requirements
where p = pole pairs, and subsequently the number of • accepted loading practice of the generating sets (e.g. 90
poles = 2 * p % of Pr)
Generator power definitions:
Sr = rated output, rated apparent power in kilo- 15.1.4. Basic requirements
volt-amperes kVA For a.c. generating sets used onboard ships and offshore
Sr = Pr/cos nr installations which have to comply with rules of classifica-
Pr = rated active power in kilowatts kW tion society (Class), the specific requirements of the Class
cos nr = rated power factor shall be observed.
cos nr = Pr/Sr The main source of electrical power consists of at least two
generating sets, and a shaft generator may be considered to
The generator rated active power limit Pr should match
be one of the required generators if capable of operating in
with the diesel rated output power PDIESEL taking into ac-
parallel. The capacity of the generating sets shall be such
count the efficiency hGEN of the generator.
that in the event of any one set being stopped it will still be
Pr = hGEN * PDIESEL possible to supply those services necessary to provide nor-
Generator hGEN is typically 95…97 % at full load and cos n mal operational conditions of propulsion, safety and mini-
0,8 mum comfortable conditions of habitability.
In the following there are some common basic require-
ments of the generating set performance.
Frequency and voltage variations in a.c. installations:

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 15. Electrical power generation and management

Table 15.1. 15.2.2.Power factor

Rated power factor cos nr of the generator shall be se-
Load condition: Steady state Transient state
lected in accordance with the network load cos n, which
Freq./speed regularly is 0,8 … 0,85.
95 – 105 % 90 – 110 %
regulation
In a diesel electric drive vessel e.g.: with cyclo converters
A.c. voltage and/or low loading of propulsors, the power factor is
97,5 – 102,5 % 85 – 120 %
regulation 0,7…0,8 and the generators are to be dimensioned accord-
ingly.
Although the Class sets requirements for sudden load The most common power factor for generators is 0,8.
changes, the general recommendation is to apply electrical
loads in a ramp function rather than in sudden load steps. 15.2.3.Generator reactances
Reference is also made to Chapter 2: Operating Ranges and
loading capacity. An important issue with regard to short circuit figures and
starting capacity in the network is the generators’
subtransient reactance xd”. The xd” is typically 15…20 (up
15.2.Electric power generation to 25) %.
Generally a high xd” causes a lower short circuit current
15.2.1.General dimensioning criteria but reduces the starting capacity of high power motors in
The generator voltage, capacity and number of units are the network due to an excessive voltage drop.
basically defined from the operation mode with the maxi- A very low xd” increases the generator size in comparison
mum connected electric load, which can be expected used to a high xd”, but the possibility to choose a specific xd” is
simultaneously. The demanding operation mode is usually somewhat restricted.
manoeuvring or cargo handling, while max speed at sea in a A compromise between high starting capacity and low
diesel-electric ship may be the actual mode. short circuit level of the network, and low distortion level
It should be considered that at least one generating set of the distorted voltage waveform in a ‘polluted’ vessel, is
should be stand-by offering flexibility to perform mainte- to be done when deciding the generator reactances.
nance work on any other generating set.
For example, in an uncomplicated vessel the generator ca- 15.2.4.Generator protection and
pacity could be selected in a way that one unit is suitable for switchgear
port and sea conditions, and two units for manoeuvring Generator set switchgear, control gear and monitoring
conditions having a 3rd unit as a stand-by. equipment is usually mounted off the generating set. All
General dimensioning criteria with respect to power, components incorporated in the switchgear shall be ade-
among others: quately rated to suit the generating set and the specified
• type of vessel mains operation, including the prospective fault current.
• operation mode and application The generator is basically protected by the generator
breaker and protection devices, usually being tripped by
• requirements of the connected load the following protection functions:
• load power factor cos n
• short circuit
• cost efficient loading level, optimum specific fuel con-
• overload
sumption
• time delayed over-current
• redundancy requirements
• reverse-power
• starting characteristics of high power motors
• differential-current
Due consideration is to be given to the transient frequency
and voltage characteristics of the generating set during and • voltage protections (over and under voltage release)
after a sudden load change. Any particular requirement of • earth fault
the load acceptance shall be subject to agreement between
• stator RTD temperature HI/HI
the customer and Wärtsilä.
Generating set protection systems mainly related to the
engine are set in the chapter for Automation System, and
comprise among others:
• load shedding

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 15. Electrical power generation and management

• overspeed droop setting, as well as the dynamical performances of the

• engine shutdown governor, shall be equal for all parallelling generators in or-
der to have a proportional load sharing.
• emergency stop
An isochronous load sharing for parallelling generators is
• major alarm from the speed governor. possible with an electronic governor. All parallelling gener-
The temperature rise of the generator windings is recom- ators are to have the same maker and type of electronic
mended to be one class lower than the temperature class of governor. The isochronous mode governor will maintain a
the insulation, e.g.: constant speed up to 100 % load.
Insulation class/Temperature rise: F/B or H/F
15.2.7. AVR (Automatic Voltage Regulator)
15.2.5. Motor starting capacity of the The AVR controls the generator voltage and the reactive
network load sharing. The brushless exciter-AVR system is to de-
The starting capacity of the electrical network depends tect changes in terminal voltage (e.g. caused by a sudden
mainly on the connected spare generator capacity, genera- load change) and to vary the field excitation as required ba-
tor xd”, xd’ and allowed voltage drop. The maximum al- sically to restore the terminal voltage of the generator.
lowed transient voltage drop is 15 %, which in some cases The AVR, including the spare AVR where applicable, shall
is too much for sensitive equipment. be tested and approved by the Class together with the gen-
The starting characteristics of the most power consuming erator forming a unit.
motor or consumer is to be carefully checked. The genera- The exciter and AVR are normally supplied from the gen-
tor manufacturer is to be informed (preferably at the offer- erator (shunt excitation) or sometimes from a
ing stage) on the motor characteristics, operation and shaft-mounted external Permanent Magnet Generator
starting method in order to evaluate the expected voltage (PMG), which is used on generators, e.g. in a network with
drop. notable voltage distortion.
An excessive voltage drop causes generator dimensioning In order to maintain a possible network short-circuit cur-
adjustments and/or means of alternative motor starting rent, high enough (at least 3 * IN) to trip the generator or
methods, e.g. soft starting device. achieve selectivity in the distribution, a booster
(short-circuit excitation) circuit is provided for the shunt
15.2.6. Speed Governor excitation.
The reactive load sharing of parallelling generators is pro-
The speed governor is a device, which senses the speed of
vided by the AVR using parallelling compensation circuits
the engine and controls the fuel flow to the engine to main-
tain the speed at the desired level to meet changes in load called:
output. Governor types are mainly hydraulic/mechanical • voltage droop compensation
or electronic, which are used in more complex projects. • crosscurrent compensation
In electrical terms, the speed governor controls the gener- The droop compensation is the most commonly used cir-
ator’s and network’s frequency and the active load sharing cuit for reactive load sharing and is possible with an ana-
by speed droop feedback or an ‘isochronous’ (zero droop) logue or a digital AVR. The voltage droop depends on the
mode. reactive load, i.e. a decrease in voltage for an increase in re-
The steady state frequency characteristics depend mainly active load.
on the performance of the engine speed governor, while The crosscurrent compensation is a more complex
the transient frequency characteristics depend on the com- method for reactive load sharing. The voltage is maintained
bined behaviour of all engine system components. constant without ‘droop’, and the reactive load is balanced.
Basic definition of speed droop: Manual voltage control in the main switchboard as a
A decrease in speed reference for an increase in load, i.e. back-up is generally provided only on the request of the
the % of the current speed reference by which the speed customer.
reference is drooped (decreased) from zero to full load.
An external speed setting from the power management 15.2.8. Shaft generators
system compensates the speed droop effect keeping the A shaft generator (SG) is driven by a main propulsion unit,
frequency stable in long term steady state conditions. which usually is intended to operate at constant speed in a
Speed droop based load sharing is possible with both a hy- CPP installation.
draulic/mechanical and an electronic governor. For most Shaft generators are normally connected to:
applications a droop of 3…5 % is recommended. The

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 15. Electrical power generation and management

• a secondary PTO from a step-up gear (generator runs // size of EDG. Allowance is also recommended for possible
propeller shaft) future additional emergency loads.
• a primary PTO from a step-up gear (generator runs // The emergency consumers comprises e.g.: emergency
engine) lighting, navigational and communication equipment, fire
alarm systems, fire and sprinkler pumps, bilge pump, wa-
• an engine free end
ter-tight doors, person lifts, steering gear.
A constant frequency shaft generator may be an alternative
Many shipowners have additional requirements with re-
in a vessel with a diesel driving a FPP.
gard to EDG-supplied services as precautionary measures
It is recommended to provide the main engines with elec- against blackout, e.g.: essential (non-emergency) auxiliaries
tronic speed governors when shaft generator installations for electric power generation and propulsion. This further
are applied in multi engine installations (twin-in/sin- loading of EDG shall of course be reflected in the EDG
gle-out). size, and a shedding system for non-emergency consumers
The SG is basically dimensioned with regard to the operat- to be provided and trip, in case the EDG should be over-
ing mode, electric load at sea and thruster (or other high loaded.
power consumer) sizes. It is not recommended to use the EDG as a harbour gener-
In the case with secondary PTO the shaft generator speed ator, ref. Solas Ch. II-1 Part D Reg. 42. 1.4 and Reg. 43. 1.4.
nrG and the gear ratio is to correspond to a suitable high
speed of the main engine, in order to have power enough to
run both shaft generator and CPP at a constant speed at 15.3.Electric power management
sea. In the manoeuvring mode the propeller cavitation can system (PMS)
be reduced, by selecting a 2-stage (speed) PTO gear en-
abling a lower main engine and propeller speed. 15.3.1.General
The main task of the electric power management (PMS) is
15.2.9.Earthed neutral
to control the generation plant and to ensure the availabil-
The vessels’ generation and distribution systems are ordi- ity of electrical power in the network as well as to avoid
nary insulated in low voltage installations as well as for blackout situations.
tankers. The PMS basically controls the starting/stopping and syn-
The network in medium voltage installations is mostly chronising of a generator to the network, frequency moni-
earthed via a high resistance connected to the generators’ toring, steady state load sharing between on-line
neutral. The rating of the earthed neutral system shall be generators, blackout starting, shaft generator, gear clutches
defined taking into account the ratings of all components and executes load tripping when the power plant is over-
of electrical equipment in the generation circuit. loaded (load shedding).
Earthed neutral options are e.g. a separate earthing trans- The main busbar is normally subdivided into at least two
former with a resistance, a low resistance earthed neutral or parts connected by bustie breakers, and the connection of
a direct earthed neutral. generating sets and other duplicated equipment shall be
The earthed neutral cabinet is normally delivered by the equally divided between the parts.
switchgear supplier and co-ordinated with the generator
supplier. 15.3.2.Control modes
The PMS is to have redundant hierarchy of control modes,
15.2.10.Emergency diesel generator the following provisions being typical:
The emergency source of electrical power shall be • automatic, independently derived signals without man-
self-contained independently from engine room systems ual intervention
with more stringent requirements as to operability when
• remote control, manually initiated
heeling and listing as well as location, starting arrangements
and load acceptance. • local control, e.g. hand or electric
The emergency diesel generator (EDG), supplying the The automatic mode is the normal operation main system.
emergency consumers required by Rules, is basically It is recommended that means is to be provided to start an
dimensioned according to worst loading case of fire fight- engine locally and to synchronise manually at the main
ing, flooding and blackout start. switchboard in case of the PMS failure. The back-up sys-
tem is recommended to be an independent operating sys-
The starting capacity of the emergency network shall be
tem, hard wired and with galvanic isolation to the main
specially considered, as the most power consuming emer-
system.
gency electrical consumer (motor) often determines the

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Monitoring of the generating set operation to verify cor- The PMS controls the active (kW) load sharing over the
rect functioning by measurement or protection and super- speed governor:
visory control parameters in accordance to Class and • droop control, characteristics about 4 %
requirements are set in the chapter for Automation Sys-
tem. • isochronous load sharing, possible by means of an elec-
tronic speed governor taking care of ramping up, load
sharing and ramping down; PMS only connects the set
15.3.3. Main breaker control
and after allowance by the governor disconnects the set.
The following main breakers in the main switchboard are Active load sharing between diesel generators is normally
typically controlled from the PMS: proportional (balanced). The droop setting shall be equal
• diesel generator for all parallelling generators in order to have a propor-
• shaft generator tional load sharing.
But some feature mode options could promote an eco-
• bustie breaker
nomical and environment-friendly operation of the en-
• shore connection gines, e.g.:
• h i g h p o w er c ons ume rs , e .g.: bow th ruster, • master-topping up, i.e. master(s) with constant optimal
AC-compressor, load and a topping up set taking care of the load varia-
• emergency switchboard connection tions
• sequencing of the master-topping up units
15.3.4. Blackout start and precautionary
measures 15.3.6. Shaft generator load transfer
In case of blackout in the main switchboard (MSB) the re- The PMS controls the main engine in shaft generator (SG)
lated generating sets get a starting order and the first avail- applications giving priority to the electric generation, in-
able generating set to ‘run up’ will connect to the MSB, and cluding possible propulsion load reduction where applica-
the following units to be automatically synchronised. ble.
Precautions against failing blackout start are among oth- Operating with SG supplying the main switchboard (MSB)
ers: in parallel with the connected propulsion line, the fre-
• booster and fuel supply pumps connected to emergency quency may be unstable in rough sea, etc. It is recom-
switchboard (ES) mended to use the SG independently supplying the MSB or
part of it. If 2 SG are available e.g. in a twin-screw vessel,
• pre lubricating pump connected to ES
the MSB should be split into 2 parts, each part being sup-
• sequential re-start of essential pumps, fans and heavy plied by a dedicated SG.
consumers to achieve a loading ramp rather than big
The load transfer from/to the auxiliary diesel generator(s)
loading steps
should normally be on a short time basis, i.e. parallelling
Precautions against total loss of propulsion (diesel me- only for the time of unloading the generator(s) followed by
chanical concepts) in a blackout situation could be follow- generator breaker opening.
ing measures among others:
The shaft generator is typically supplying thruster(s) in a
• essential ME pumps are engine driven separate network during the manoeuvring mode.
• essential propulsion train pumps are gear driven In the following a typical example of load transfer at sea to
• essential electrical pumps and fans for propulsion are a running shaft generator when the thrusters have been dis-
connected to ES connected:
• operate with split network • assure that the main engine load is stable and that the
constant speed mode is selected
15.3.5. Parallelling of generators, load • synchronise the SG-section and the MSB (i.e. the auxil-
sharing iary diesel engine(s) are usually synchronised to the main
engine) and close the SG-section bustie breaker
The PMS provides automatic synchronising of auxiliary
diesel generators i.e. frequency adjustment to bring the in- • transfer load to SG by unloading the auxiliary diesel gen-
coming set into synchronism and phase with the existing erator(s) according to unloading rate
system, considering possible restrictions (e.g.: short circuit • open the auxiliary diesel generator’s breaker(s) when un-
level) regarding max number of generators allowed to be loading trip level is reached
connected to the MSB. • stop the auxiliary diesel engine(s)

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15.3.7.Load dependent start/stop In order to protect the generator(s) against sustained over-
load, and to ensure the integrity of supplies to services re-
The PMS includes functions for automatic load dependent
quired for propulsion and steering as well as the safety of
start/stop of diesel generation sets. the ship, suitable load shedding arrangements shall be ar-
The start/stop limits and start order in an installation with ranged.
several parallelling generating sets are set to achieve an op-
Typical consumers that may be tripped are e.g.:
timal loading of the engines in the specific operation mode
of the vessel. The PMS calculates the network’s nominal • galley consumers
power and total generator load over a defined period of • AC-compressors
time and compares that against the load dependent • accommodation ventilation
autostart/autostop limits. The objective is to ensure that
the actual load is supplied by an appropriate number of • reduction of propulsion power
generating sets to achieve best possible energy efficiency
and fuel economy. 15.3.10.Special applications, e.g.: Auxiliary
Propulsion Drive (APD)
15.3.8.Power reservation for heavy A special application providing limited redundancy with
consumers respect to increased availability of the vessel’s propulsion
Heavy consumers may be connected to a power reserva- system is the so-called Auxiliary Propulsion Drive (APD).
tion system in the PMS, which checks if there is enough re- The principle idea of this solution is that the ship can be
serve power capacity in the network upon a start request propelled by the auxiliary generating sets, by using the shaft
from the heavy consumer. If necessary the PMS will start generator as an electric motor, in case the main engine
and synchronise the next standby unit, and gives the start (ME) is not available.
permission to the heavy consumer when the needed start- The benefit of the combined shaft generator and APD is,
ing capacity is available. among others, an increase of safety when it is used as
back-up propulsion in e. g. following operating modes:
15.3.9.Load shedding (preference tripping) • booster mode, both ME and PTO are driving the pro-
peller
Auto start function is not fast enough as blackout preven-
tion after rapid and large loss of power generating capacity, • standby mode, ME disconnected for maintenance and
e.g. after tripping of a generator. APD is connected if manoeuvring is required
• emergency mode (take me home), APD is used to propel
the ship if ME fails

110 Marine Project Guide W20 - 1/2002

 15. Electrical power generation and management

15.4. Typical one line main diagrams

4 ADG low voltage network

ES

EE G
MSB
AE G BT ~
~

MCC
AE G

AE G
MC C

AE G BT

3 ADG + 2 SG low voltage network

ES

EE G

ME MSB ~
~
SG BT

AE G MCC

AE G

MCC
AE G

SG BT

ME

Marine Project Guide W20 - 1/2002 111

 15. Electrical power generation and management

Diesel electric ship, medium voltage network

ES

EE G

~
~

MSB/MV MSB/LV

ME G BT MCC

AC
MCC
ME G AC

PM

PM

ME G AC
MCC
BT
ME G BT
MCC

112 Marine Project Guide W20 - 1/2002

 16. Foundation

16. Foundation
16.1. General The elongation of holding down bolts can be calculated
from the formula:
Engines can be either rigidly mounted on chocks, or resil-
iently mounted on rubber elements.
Wärtsilä should be informed about existing excitations
(other than Wärtsilä supplied engine excitations) and natu-
ral hull frequencies, especially if resilient mounting is con- DL = bolt elongation [mm]
sidered.
F = tensile force in bolt [N]
Dynamic forces caused by the engine are shown in the
L i= part length of bolt with diameter D i [mm]
Chapter for Vibration and noise.
Di = part diameter of bolt with length Li [mm]
Lateral supports as shown in 2V69A0236 shall be fitted
16.2. Steel structure design against the engine block. The wedge type supports shall be
The system oil tank may not extend under the reduction lightly knocked into position when the engine is hot and
gear, if the engine is of dry sump type and the oil tank is lo- secured with a tack weld. Minimum bearing surface on the
cated beneath the engine foundation. Neither should the wedges is 80%.
tank extend under the support bearing, in case there is a The engine can be installed on either steel or resin chocks.
PTO arrangement in the free end. The oil tank must also be The chocking arrangement shall be sent to the classifica-
symmetrically located in transverse direction under the en- tion society and Wärtsilä for approval.
gine.
Steel chocks
The top plates of the engine girders are normally inclined
16.3. Mounting of main engines outwards with regard to the centre line of the engine. The
Main engines can be either rigidly mounted on chocks, or inclination of the supporting surface should be 1/100. The
resiliently mounted on rubber elements. seating top plate should be designed so that the wedge-type
steel chocks can easily be fitted into their positions. The
The foundation and the double bottom should be as stiff
wedge-type chocks also have an inclination of 1/100 to
as possible in all directions to absorb the dynamic forces
match the inclination of the seating. If the rider plate of the
caused by the engine, reduction gear and thrust bearing.
engine girder is fully horizontal, a chock is welded to each
The foundation should be dimensioned and designed so point of support. The chocks should be welded around the
that harmful deformations are avoided. periphery as well as through holes drilled for this purpose
at regular intervals to avoid possible relative movement in
16.3.1. Rigid mounting the surface layer. The welded chocks are then face-milled
Main engines are normally rigidly mounted on the seating, to an inclination of 1/100. The surfaces of the welded
either on steel or resin chocks. chocks should be large enough to fully cover the
wedge-type chocks.
The engine has 4 mounting brackets cast to the engine
block. Each bracket has a threaded hole for an M16 jacking The supporting surface of the seating top plate should be
screw and two Ø22 holes for M20 holding down bolts. machined so that a bearing surface of at least 75% is ob-
tained.
The bolt closest to the flywheel at either side of the engine
shall be made as a Ø23H7/m6 fitted bolt. All other bolts The cutout in the chocks for the clearance bolts should be
are clearance bolts. about 2 mm larger than the bolt diameter. The maximum
cut out area is 20%. Holes are to be drilled and reamed to
The clearance bolts shall be through bolts with lock nuts at the correct tolerance for the fitted bolts after that the cou-
both the lower and upper ends. Ø22 holes can be drilled
pling alignment has been checked and the chocks have
into the seating through the holes in the mounting brack-
been lightly knocked into position.
ets.
In order to assure proper fastening and to avoid bending
In order to avoid bending stress in the bolts and ensure stress in the bolts, the contact face of the nut underneath
that the bolts remain tight the contact face of the nut under the seating top plate should be counterbored.
the seating top plate shall be spotfaced.
Holding down bolts shall be long enough to ensure an
elongation DL ³ 0.25 mm when tightened.

Marine Project Guide W20 - 1/2002 113

 16. Foundation

An effective bolt length of 160 mm (between the nuts) will Resin chocks
ensure a sufficient elongation. It is recommended to fit dis- Installation of main engines on resin chocks is possible
tance sleeves with L ³ 95 according to drawing
provided that the requirements of the classification societ-
4V33F0214 under the seating top plate. M20 8.8 bolts can
ies are fulfilled.
be used. Tightening torque 390 - 430 Nm.
During normal conditions, the support face of the engine
feet has a maximum temperature of about 75°C, which
Distance sleeve (4V33F0214) should be considered when selecting the type of resin.
The total surface pressure on the resin must not exceed the
maximum value, which is determined by the type of resin
and the requirements of the classification society. It is rec-
ommended to select a resin type, which has a type approval
from the relevant classification society for a total surface
pressure of 5 N/mm² (typical conservative value is ptot<
3.5 N/mm²).
In order to assure proper fastening and to avoid bending
stress in the bolts, the contact face of the nut underneath
the seating top plate should be counterbored.
If the engine is installed on resin chocks, the seating shall
be as shown in 2V69A0236, except that the 1:100 inclina-
tion is not necessary.
When installing an engine on resin chocks the following is-
sues are important:
• Sufficient elongation of the holding down bolts
• Maximum allowed surface pressure on the resin ptot =
pstatic + pbolt
• Correct tightening torque of the holding down bolts
The elongation DL of the holding down bolts should be:
DL [mm] ³ 0.12 for a surface presure on the resin ptot £
3.5 MPa
DL [mm] ³ 0.0343 x ptot [MPa] for p tot > 3.5 MPa
The recommended dimensions of resin chocks are 140 x
410 mm. This gives gives a deadweight loading pstatic on the
resin which is presented in the table below.

Table 16.1. Total load on resin chocks

Engine Dwt load P static [Mpa] Bolt tension load Pbolt [Mpa] Total load Ptotal [Mpa]
4L20 0.33 2.9 3.23

5L20 0.37 2.9 3.27

6L20 0.40 2.9 3.30

8L20 0.50 2.9 3.40

9L20 0.58 2.9 3.48
Wet engine with wet sump with standard equipment and flywheel.

114 Marine Project Guide W20 - 1/2002

 16. Foundation

Most resin types can take at least 3.5 MPa and the bolt To ensure sufficient elongation a distance sleeve according
holding down force (pbolt) can be chosen to produce 3 MPa to drawing 4V33F0214 with L ³ 45 mm shall be fitted un-
on the resin. This corresponds to a bolt tension of 83 000 N der the seating top plate
(with recommended chock dimensions) and a tightening
torque of about 305 Nm tightening the bolts to 53% of
yield, assuming M20 8.8 bolts.

Main engine seating (2V69A0236a)

View from above

Marine Project Guide W20 - 1/2002 115

 16. Foundation

Main engine seating (2V69A0236a)

End view

Chocking of main engines (2V69A0238b)

From 2V69A0237

116 Marine Project Guide W20 - 1/2002

 16. Foundation

Mounting bracket (2V10A1836)

Marine Project Guide W20 - 1/2002 117

 16. Foundation

16.3.2.Resilient mounting
In order to reduce vibrations and structure borne noise,
main engines may be resiliently mounted on rubber ele-
ments.

Mounting bracket (2V10A1837)

118 Marine Project Guide W20 - 1/2002

 16. Foundation

16.4. Mounting of generating sets

16.4.1. Alternator feet design
Instructions for designing the feet of the engine alternator and the distance between its holding down bolts
(4V92F0134b)

Marine Project Guide W20 - 1/2002 119

 16. Foundation

16.4.2.Resilient mounting Note!

Generating sets, comprising engine and generator To avoid induced oscillation of the generating set, the fol-
mounted on a common base plate, are usually installed on lowing data must be sent by the shipyard to Wärtsilä at the
resilient mounts on the foundation in the ship. design stage:
The resilient mounts reduce the structure borne noise • Main engine speed [RPM] and number of cylinders
transmitted to the ship and also serve to protect the gener- • Propeller shaft speed [RPM] and number of propeller
ating set bearings from possible fretting caused by hull vi- blades
bration. The selected number of mounts and their final position is
The number of mounts and their location is calculated to shown in the generating set drawing.
avoid resonance with excitations from the generating set
engine, the main engine and the propeller. Seating
The seating for the common base plate must be rigid
enough to carry the load from the generating set. The rec-
ommended seating design is shown in the drawing below.
Recommended design of the generating set seating (3V46L0720c)

120 Marine Project Guide W20 - 1/2002

 16. Foundation

If the generating set will be installed directly on a deck or

on the tank top, the alternative design shown in drawing
4V46L0296 can be permitted.
Alternative design of seating (4V46L0296)

The lateral distance between the mounts varies between

1340 mm and 1640 mm depending on the number of cylin-
ders of the engine and the type of generator.
Rubber mounts
Conical mounts in natural rubber are used.
The mounts are equipped with an internal adjustable cen-
tral buffer. Hence, no additional side or end buffers are re-
quired to limit the movements due to ship motions
Particularly with the alternative foundation design (see
drawing 4V46L0296), care must be taken that the mounts
will not come in contact with oil, oily water or fuel.
The mating surfaces of the common base plate is delivered
machined, with holes for attaching the mounts which are
delivered separate.

Marine Project Guide W20 - 1/2002 121

 16. Foundation

Rubber mounts (3V46L0706)

Installation of the generating set

A correct mounting of the generating set requires that all
rubber elements are equally compressed, i.e. the load on
each mount is equal. The installation procedure is:
• Remove the M27x2 nut and the washer from the mount.
• Attach each mount to the common base plate by fitting
the washer on the central buffer and tighten the nut by
hand (see drawing 3V46L0706).
• Lower the installation load onto the mounts, loosen the
nut.
• Jacking screws are used for levelling the installation.
Holes for the jacking screws are pre-drilled before deliv-
ery. M20 x 160 DIN933 8.8 jacking screws can be used.
Jacking screws are supplied by the shipyard.
• Would the screw turn out to be too short, temporary
chocks can be used to increase the lift.
• To avoid that the generating set weight is resting on the
internal buffer instead of on the rubber it is important to
check that all internal buffers can easily be turned by ap-

122 Marine Project Guide W20 - 1/2002

 16. Foundation

plying a spanner to the top hexagon (S = 19). If this is not The mounts should preferably be allowed to settle for a
possible, remove the installation load progressively until minimum of 48 hours, due to initial creeping, before lining
all buffers can be turned freely. Turn the internal buffer up pipework, etc.
counter clockwise (upwards) and re-lower the installa- The transmission of forces emitted by the engine is
tion onto the mounts. Repeat the above procedure until 10...30% when using rubber mountings compared to rigid
all buffers can be rotated freely with the full installation mounting.
load applied.
• The correct deflection of the mounts is between 4 and
10 mm depending on the weight of the generating set
16.5. Reduction gear foundations
and the selected quality of the rubber. The calculated The engine and the reduction gear must have common
compressed height of the mounts is shown in the gener- foundation girders.
ating set drawing.
• Check that the mounts are evenly compressed. The
compressed height of all mounts must be within 2.0 mm.
16.6. Free end PTO driven
Adjustments in height shall be made using machined equipment foundations
chocks. If shims are used the minimum thickness of a
The foundation of the driven equipment must be inte-
shim is 0.5 mm and only one shim per mount is permit-
grated with the engine foundation.
ted.
• Check that the seating of each mount is horizontal. This
is done by measuring the compressed height of each 16.7. Flexible pipe connections
mount on all sides. The difference must not exceed 0.5
When the engine or generating set is resiliently installed, all
mm. connections must be flexible and no grating nor ladders
Adjustments are made with wedge type chocks. may be fixed to the engine or generating set. When install-
• Set the internal buffer working clearance for each ing the flexible pipe connections, unnecessary bending or
mount: stretching should be avoided. The external pipe must be
precisely aligned to the fitting or flange on the engine. It is
• Turn the internal buffer counter clockwise (upwards) to
very important that the pipe clamps for the pipe outside the
the maximum upper position.
flexible connection must be very rigid and welded to the
• Turn the internal buffer two full turns clockwise (down- steel structure of the foundation to prevent vibrations,
wards). which could damage the flexible connection.
• Finally, tighten the nut with a torque of 300 Nm. While
doing this the top hexagon must be secured with a span-
ner

Marine Project Guide W20 - 1/2002 123

 17. Vibration and noise

17. Vibration and noise

17.1.General
Dynamic forces and moments caused by the engine appear
from the table. Due to manufacturing tolerances some
variation of these values may occur.
Coordinate system of the external torques

17.2.External forces and couples

Table 17.1. External forces Table 17.2. External couples

FZ = 0, FY = 0 and FX = 0 for 5, 6 and 9 cylinder engines MZ = 0, MY = 0 for 4, 6 and 8 cylinder engines

Engine Speed Frequency Fz Engine Speed Frequency MY MZ
[rpm] [Hz] [kN] [RPM] [Hz] [kNm] [kNm]
720 48 0.7 900 15 3.4 3.4
4L20 750 50 0.8 5L20 30 21 —
900 60 1.1 1000 16.7 4.2 4.2
1000 66.7 1.4 33.3 26 —
720 48 1.4 720 12 4.5 4.5
8L20 750 50 1.5 24 3.1 —
900 60 2.2 750 12.5 4.9 4.9
1000 66.7 2.7 9L20 25 3.3 —
900 15 7 7
30 4.8 —
1000 16.7 8.6 8.6
33.3 5.9 —

124 Marine Project Guide W20 - 1/2002

 17. Vibration and noise

Table 17.3. Rolling moments

Zero load
Engine Speed Frequency Full load (MX ) Frequency Full load (M X) Zero load (MX )
(M X)
[RPM] [Hz] [kNm] [kNm] [Hz] [kNm] [kNm]
4L20 720 24 10 4.8 48 7.5 1.6
750 25 9.4 5.6 50 7.5 1.5
900 30 4.8 10 60 7.4 1.4
1000 33.3 1.5 13 66.7 7.4 1.3
5L20 900 37.5 18 4.3 75 6.2 1.7
1000 41.7 18 4.3 83.3 6.3 1.8
6L20 720 36 13 1.4 72 4.2 1.2
750 37.5 12 1.9 75 4.2 1.2
900 45 9.8 4.7 90 4.7 1.3
1000 50 7.8 6.8 100 4.7 1.3
8L20 720 48 15 3.1 96 1.7 0.7
750 50 15 3.1 100 1.7 0.7
900 60 15 2.8 120 2.2 0.7
1000 66.7 15 2.6 133.3 2.2 0.7
9L20 720 54 13 3.5 108 1.1 0.5
750 56.3 13 3.5 112.5 1.1 0.5
900 67.5 14 3.6 135 1.6 0.5
1000 75 14 3.6 150 1.6 0.5

17.3. Mass moments of inertia 17.4. Air borne noise

The mass-moments of inertia of the propulsion engines The airborne noise of the engine is measured as a sound
(including flywheel, coupling outer part and damper) Are power level according to ISO 9614-2. The results are pre-
typical as follows: sented with A-weighing in octave bands, reference level 1
Engine J[kgm2 ] pW. Two values are given; a minimum value and a 90%
value. The minimum value is the smallest sound power
4L20 86 - 160
level found in the measurements. The 90% level is such
5L20 126 - 146
that 90% of all measured values are below this figure.
6L20 88 - 162
8L20 96 - 170
9L20 106 - 174
Figure 17.1. Sound power levels
130
121
120 90 % 119
114 113
110 112
109
110 MIN
105 114
Lw [d B(A)] ref 1 pW

113
109 107
100
94 104
101
99 99
90
84

80 85

70 65
74
60

50 56

40
Linear
1000

2000

4000

8000
125

250

500
63

A-w eight*
31.5

1/1 Octave band [Hz]

Marine Project Guide W20 - 1/2002 125

 18. Power transmission

18. Power transmission

18.1.General
The full engine power can be taken from both ends of the
engine. At the flywheel end there is always a flywheel for
the management of the torsional vibration characteristics
of the system and to facilitate manual turning of the engine.
The flywheel creates a natural flange connection and in
case needed also shaft connection can be provided. At the
free end a shaft connection is provided in case a power take
off is provided.

18.2.Connection to alternator
Connection engine/single bearing alternator (2V64L0071)

126 Marine Project Guide W20 - 1/2002

 18. Power transmission

Connection engine/two-bearing alternator (4V64F0001)

18.3. Flexible coupling • In case of blackout and no oil pressure the stopping of a
declutched engine is so fast that the damages are minor
The power transmission of propulsion engines is accom- even without gravity tank.
plished through a flexible coupling or a combined flexible
• The use of clutch reduces torsional stresses in elastic
coupling and clutch mounted on the flywheel. The crank- coupling while starting and stopping.
shaft is equipped with an additional shield bearing at the
flywheel end. Therefore also a rather heavy coupling can be • The clutch creates investment and maintenance costs. It
mounted on the flywheel without intermediate bearings. usually increases the length of the propulsion machinery.
The type of flexible coupling to be used has to be decided • The clutch can lead to the loss of propulsion in case of
separately in each case on the basis of the torsional vibra- automation or pressure problem.
tion calculations. • Badly adjusted clutch can cause torque peaks that cause
In case of two bearing type alternator installations a flexi- damage to elastic coupling and reduction gear.
ble coupling between the engine and the generator is re- • Dry-friction type clutch can cause smoke formation to
quired. set off the fire alarm and sparks to ignite the oil on tank
top causing engine room fire.
18.4. Clutch
The clutch is required when two or more engines are con-
18.5. Shaftline locking device and
nected to the same driven machinery like a reduction gear. brake
The clutch is also required when the engine is connected to
a reduction gear having a primary PTO. 18.5.1. Locking device
Some consideration when deciding whether to have a • A shaftline locking device is needed when the operation
clutch installed or not: of the ship makes it possible to turn the shafting by the
• In ships having more than one propeller it is possible to water flow in the propeller.
run the ship with just one propeller letting the other pro-
peller(s) to windmill. This makes it possible to save the 18.5.2. Brake
running hours of the standstill engine(s) or do mainte-
nance on them. Anyhow for safety reasons the shaft is • A shaftline brake is needed when the shaftline needs to
to be locked when working around rotating shafts in the be actively stopped. This is the case when the direction
engine. of rotation needs to be reversed.

Marine Project Guide W20 - 1/2002 127

 18. Power transmission

alternative 2 (4V62L0932)
18.6.Power-take-off from the free
end
Power take off at free end alternative 1
(4V62L0931)

128 Marine Project Guide W20 - 1/2002

 18. Power transmission

18.7. Torsional vibration Data of main alternator or shaft alternator

calculations A mass-elastic diagram or an alternator shaft drawing
showing:
A torsional vibration calculation is made for each installa-
• alternator output, speed and sense of rotation
tion. For this purpose exact data of all components in-
cluded in the shaft system are required. See the list below. • mass moment of inertia of all rotating parts or a total in-
ertia value of the rotor, including the shaft
General
• torsional stiffness or dimensions of the shaft
• Classification • material of the shaft including tensile strength and
• Ice class modulus of rigidity
• Operating modes • drawing number of the diagram or drawing
Data of reduction gear Data of flexible coupling/clutch
A mass elastic diagram showing: If a certain make of flexible coupling has to be used, the
• all clutching possibilities following data of it must be informed:
• sense of rotation of all shafts • mass moment of inertia of all parts of the coupling
• dimensions of all shafts • number of flexible elements
• mass moment of inertia of all rotating parts including • linear, progressive or degressive torsional stiffness per
shafts and flanges element
• torsional stiffness of shafts between rotating masses • dynamic magnification or relative damping
• material of shafts including tensile strength and modulus • nominal torque, permissible vibratory torque and per-
of rigidity missible power loss
• gear ratios • drawing of the coupling showing make, type and draw-
ing number
• drawing number of the diagram
Data of propeller and shafting
18.8. Turning gear
A mass-elastic diagram or propeller shaft drawing show-
ing: • A manual turning tool is provided with the engine.
• mass moment of inertia of all rotating parts including the
rotating part of the OD-box, SKF couplings and rotat-
ing parts of the bearings
• mass moment of inertia of the propeller at full/zero
pitch in water
• torsional stiffness or dimensions of the shaft
• material of the shaft including tensile strength and
modulus of rigidity
• drawing number of the diagram or drawing

Marine Project Guide W20 - 1/2002 129

 19. Engine room layout

19. Engine room layout

19.1.Crankshaft distances
Minimum crankshaft distances have to be followed in or-
der to provide sufficient space between engines for mainte-
nance and operation.

19.1.1.In-line engines
Engine room arrangement, generating sets (2V69C0278d)

ENGINE A B C D E F
4L20 1800 700 1200 845 1970 1270
5L20 1800 700 1200 845 1970 1270
6L20 1800 1000 1200 845 1970 / 2020 1270 / 1420
8L20 1800 1300 1200 845 2020 / 2170 1420 / 1570
9L20 1800 1300 1200 845 2170/2400 1570/1800
A = Minimum height when removing a piston
B = Camshaft overhaul distance
C = Charge air cooler overhaul distance
D = Length for the door in the connecting box, from engine block
E = Min. distance of engines dependent on common base plate
F = Width of the common base plate dependent on width of the alternator

130 Marine Project Guide W20 - 1/2002

 19. Engine room layout

Engine room arrangement, main engines TC in free end (2V69C0275b)

Engine A B C D
4L20 1800 700 1200 845
5L20 1800 700 1200 845
6L20 1800 1000 1200 845
8L20 1800 1300 1200 845
9L20 1800 1300 1200 845
A = Minimum height when removing a piston
B = Camshaft overhaul distance
C = Charge air cooler overhaul distance
D = Length for the door on the connecting box, from engine block

Marine Project Guide W20 - 1/2002 131

 19. Engine room layout

Engine room arrangement, main engines TC in driving end (2V69C0276)

Engine A B C D
6L20 1800 1000 1200 1010
8L20 1800 1300 1200 1010
9L20 1800 1300 1200 1010
A = Minimum height when removing a piston
B = Camshaft overhaul distance
C = Charge air cooler overhaul distance
D = Length for the door on the connecting box, from engine block

132 Marine Project Guide W20 - 1/2002

 19. Engine room layout

19.1.2. Father-and-son arrangement longitudinal space, so that there is no need to transport

parts over insulation box or rocker covers.
When connecting two engines of different type and/or
size to the same reduction gear the minimum crankshaft Separate lifting arrangement for overhauling turbocharger
distance has to be evaluated case by case. However, some is required (unless overhead travelling crane, which also
general guidelines can be given: covers the turbocharger is used). Turbocharger lifting ar-
rangement is usually best handled with a chain block on a
• It is essential to check that all engine components can be rail located above the turbocharger axis.
d i s m o u n ted . The mos t c rit ic als are usua l l y
See Chapter for General data and outputs for the necessary
turbochargers and charge air coolers.
hook heights.
• Special care has to be taken checking the maintenance
platform elevation between the engines to avoid struc- 19.2.3. Maintenance platforms
tures that obstruct maintenance.
In order to enable efficient maintenance work on the en-
19.1.3. Distance from adjacent gine, it is advised to build the maintenance platforms on
intermediate/propeller shaft recommended elevations. The width of the platforms
should be at minimum 800 mm to allow adequate working
Some machinery arrangements feature an intermediate space. The surface of maintenance platforms should be of
shaft or propeller shaft running adjacent to engine. To al- non-slippery material (grating or chequer plate).
low adequate space for engine inspections and mainte-
nance there has to be sufficient free space between the
intermediate/propeller shaft and the engine. 19.3. Handling of spare parts and
To enable safe working conditions the shaft has to be cov- tools
ered. It must be noticed that also dimensions of this cover
have to be taken into account when determining the shaft Transportation arrangement from engine room to storage
distances in order to fulfil the requirement for minimum and workshop has to be prepared for heavy engine compo-
nents. This can be done with several chain blocks on rails
free space between the shaft and the engine.
or alternatively utilising pallet truck or trolley. If transpor-
tation must be carried out using several lifting equipment,
19.2. Space requirements for coverage areas of adjacent cranes should be as close as pos-
maintenance sible to each other.
Engine room maintenance hatch has to be large enough to
19.2.1. Working space around the engine allow transportation of main components to/from engine
room.
The required working space around the engine is mainly
It is recommended to store heavy engine components on
determined by the dismounting dimensions of some en-
slightly elevated adaptable surface e.g. wooden pallets. All
gine components, as well as space requirement of some
engine spare parts should be protected from corrosion and
special tools. It is especially important that no obstructive
excessive vibration.
structures are built next to engine driven pumps, as well as
camshaft and crankcase doors. On single main engine installations it is important to store
heavy engine parts close to the engine to make overhaul as
However, also at locations where no space is required for
quick as possible in an emergency situation.
any engine part dismounting, a minimum of 1000 mm free
space everywhere around the engine is recommended to be
reserved for maintenance operations. 19.4. Required deck area for
service work
19.2.2. Engine room height and lifting
equipment During engine overhaul some deck area is required for
cleaning and storing dismantled components. Size of the
It is essential for efficient and safe working conditions that service area is dependent of the overhauling strategy cho-
the lifting equipment are applicable for the job and they are sen, e.g. one cylinder at time, one bank at time or the whole
correctly dimensioned and located. engine at time. Service area should be plain steel deck
The required engine room height depends on space reser- dimensioned to carry the weight of engine parts.
vation of the lifting equipment and also on the lifting and
transportation arrangement. The minimum engine room
height can be achieved if there is enough transversal and

Marine Project Guide W20 - 1/2002 133

 20. Transport dimensions and weights

20. Transport dimensions and weights

20.1.Lifting of engines
Lifting of generating sets (3V83D0300c)

Lifting of main engines (3V83D0285b)

134 Marine Project Guide W20 - 1/2002

 20. Transport dimensions and weights

20.2. Engine components

Turbocharger and cooler inserts (4V92L1282)

Marine Project Guide W20 - 1/2002 135

 20. Transport dimensions and weights

Major spare parts (4V92L1283)

136 Marine Project Guide W20 - 1/2002

 21. Dimensional drawings

21. Dimensional drawings

Dimensional drawings can be found in the CD-ROM in-
cluded in the back cover pocket of this project guide. The
drawing formats are Adobe portable document file (.pdf)
and AutoCAD (.dxf).
List of the drawings:
3V58E0584 4L20 Diesel alternator set LF
3V58E0580a 5L20 Diesel alternator set LF
3V58E0553b 6L20 Diesel alternator set LF
3V58E0552b 8L20 Diesel alternator set LF
3V58E0549b 9L20 Diesel alternator set LF
4V58E0541e 6L20 Diesel engine LD
4V58E0533c 8L20 Diesel engine LD
4V58E0534d 9L20 Diesel engine LD
4V58E0564 4L20 Diesel engine LF
4V58E0568a 5L20 Diesel engine LF
4V58E0560b 6L20 Diesel engine LF
4V58E0559b 8L20 Diesel engine LF
4V58E0561a 9L20 Diesel engine LF

Marine Project Guide W20 - 1/2002 137

 22. ANNEX

22. ANNEX
22.1.Ship inclination angles
Inclination angles at which main and essential auxiliary machinery is to operate satisfactorily (4V92C0200a)

Lloyd’s Register of Det Norske American Bureau Germanischer Bureau Veritas

Classification society
Shipping 2000 Veritas 1999 of Shipping 2000 Lloyd 1998 2000
Main and aux. engines
Paragraph Pt.5 Ch.1 Sec.3 Pt.4 Ch.1 Sec.3 Pt.4 Ch.1 Sec.1 Pt.1 Ch.2 Sec.1 Pt.C Ch.1 Sec.1
Par.3.6 Par.B200 Par.7.9 Par.C 1.1 Par.2.4.1
Heel to each side 15 15 15 15 15
Rolling to each side 22.5 22.5 22.5 22.5 22.5
Ship length, L L < 100 L > 100 — — — —
Trim 5 500/L 5 5 5 5
Pitching 7.5 7.5 7.5 7.5 7.5
Emergency sets
Heel to each side 22.5* 22.5* 22.5* 22.5* 22.5*
Rolling to each side 22.5 22.5* 22.5* 22.5* 22.5*
Trim 10 10 10 10 10
Pitching 10 10 10 10 10
Electrical installation** ***
Paragraph Pt.6 Ch.2 Sec.1 Pt.4 Ch.4 Sec.2 Pt.4 Ch.1 Sec.1 Pt.1 Ch.3 Sec.1 Pt.C Ch.2 Sec.2
Par.1.9 Par.A101 Par.7.9 Par.E 1.1 Par.1.6.1
Heel to each side 15 15 15 15 15
Rolling to each side 22.5 22.5 22.5 22.5 22.5
Ship length, L L < 100 L > 100 — — — —
Trim 5 500/L 5 5 5 5
Pitching 7.5 10 7.5 7.5 7.5

Russian Maritime China Classifi- Korean Register

Classification society Reg. of Shipping Polsky Rejestr Registro Italiano cation Society of Shipping
Statkow 1990 Navale 1999
1995 1998 1995
Main and aux. engines
Paragraph VII-1.6 VII-1.6 Sec.C Ch.2 Pt.III Ch.1 5.1.103
Par.2.1.5 Sec.1.1.3.1
Heel to each side 15 15 15 15 15
Rolling to each side 22.5 22.5 22.5 22.5 22.5
Trim 5 5 5 5 5
Pitching 7.5 7.5 7.5 7.5 7.5
Emergency sets
Heel to each side 22.5* 22.5* 22.5* 22.5 22.5*
Rolling to each side 22.5* 22.5* 22.5* 22.5 22.5*
Trim 10 10 10 10 10
Pitching 10 10 10 10 10
Athwartships and fore-and-aft inclinations may occur simultaneously.
* In ships for the carriage of liquefied gases and of chemicals the emergency power supply must also remain operable to a final inclination up
to a maximum of 30 degrees
** Not emergency equipment.
*** Machinery and equipment relative to main electrical power installation require the same inclination angles as “Main and aux. engines”

138 Marine Project Guide W20 - 1/2002

 22. ANNEX

22.2. Unit conversion tables

Length
Length m in ft mile nautical mile
m 1 39.370 3.2808 6.2137e-04 5.3996e-04
in 0.0254 1 8.3333e-02 1.5783e-05 0.0000137149028078
ft 0.3048 12 1 1.8939e-04 1.6458e-04
mile 1609.3 63360 5280 1 0.86898
nautical mile 1852 72913 6076.1 1.1508 1
Values are rounded to five meaning digits where not accurate.

Length m in ft mile nautical mile

m 1 1/0.0254 1/(12*0.0254) 1/(0.0254*63360) 1/1852
in 0.0254 1 1/12 1/(63360) 0.0254/1852
ft 0.0254*12 12 1 1/(5280) 12*0.0254/1852
mile 0.0254*63360 63360 5280 1 63360*0.0254/1852
nautical mile 1852 1852/0.0254 1852/(12*0.0254) 1852/(63360*0.0254) 1
Equations are accurate.

Area
Area square m square inch square foot Area square m square inch square foot
square m 1 1550.0 10.764 square m 1 1/0.0254^2 1/(12*0.0254)^2
square inch 6.4516e-04 1 6.9444e-03 square inch 0.0254^2 1 1/144
square foot 9.2903e-02 144 1 square foot (12*0.0254)^2 144 1
Values are rounded to five meaning digits where not
accurate. Equations are accurate.

Volume

Volume cubic m l (liter) cubic inch cubic foot Imperial gallon US gallon
cubic m 1 1000 61024 35.315 219.97 264.17
l (liter) 0.001 1 61.024 3.5315e-02 0.21997 0.26417
cubic inch 1.6387e-05 1.6387e-02 1 5.7870e-04 3.6047e-03 4.3290e-03
cubic foot 2.8317e-02 28.317 1728 1 6.2288 7.4805
Imperial gallon 4.5461e-03 4.5461 277.42 0.16054 1 1.2009
US gallon 3.7854e-03 3.7854 231 0.13368 0.83267 1
Values are rounded to five meaning digits where not accurate.

Volume cubic m l (liter) cubic inch cubic foot Imperial gallon US gallon
cubic m 1 1000 1/0.0254^3 1/(12*0.0254)^3 1/0.00454609 1/(231*0.0254^3)
l (liter) 0.001 1 1/0.254^3 1/(12*0.254)^3 1/4.54609 1/(231*0.254^3)
cubic inch 0.0254^3 0.254^3 1 1/12^3 0.254^3/4.54609 1/231
cubic foot (12*0.0254)^3 (12*0.254)^3 12^3 1 (12*0.254)^3/4.54609 12^3/231
Imperial gallon 0.00454609 4.54609 4.54609/0.254^3 4.54609/(12*0.0254)^3 1 4.54609/(231*0.254^3)
US gallon 231*0.0254^3 231*0.254^3 231 231/12^3 231*0.254^3/4.54609 1
Equations are accurate but some of them are reduced in order to limit the number of decimals.

Marine Project Guide W20 - 1/2002 139

 22. ANNEX

Energy
Energy J BTU cal lbf ft
J 1 9.4781e-04 0.23885 0.73756
BTU 1055.06 1 252.00 778.17
cal 4.1868 3.9683e-03 1 0.32383
lbf ft 1.35582 1.2851e-03 3.0880 1
Values are rounded to five meaning digits where not accurate.

Mass
Mass kg lb oz
kg 1 2.2046 35.274
lb 0.45359 1 16
oz 0.028350 0.0625 1
Values are rounded to five meaning digits where not accurate.

Density
Density kg / cubic m lb / US gallon lb / Imperial gallon lb / cubic ft
kg / cubic m 1 0.0083454 0.010022 0.062428
lb / US gallon 119.83 1 0.83267 0.13368
lb / Imperial gallon 99.776 1.2009 1 0.16054
lb / cubic ft 16.018 7.4805 6.2288 1
Values are rounded to five meaning digits where not accurate.

Power
Power W hp US hp
W 1 0.0013596 0.0013410
hp 735.499 1 1.0136
US hp 745.7 0.98659 1
Values are rounded to five meaning digits where not accurate.

Pressure
Pressure Pa bar mmWG psi
Pa 1 0.00001 0.10197 0.00014504
bar 100000 1 10197 14.504
mmWG 9.80665 9.80665e-05 1 0.0014223
psi 6894.76 0.0689476 703.07 1
Values are rounded to five meaning digits where not accurate.

Massflow

Massflow kg / s lb / s
kg / s 1 2.2046
lb / s 0.45359 1
Values are rounded to five meaning digits where not accurate.

140 Marine Project Guide W20 - 1/2002

 22. ANNEX

Volumeflow
Volumeflow cubic m / s l / min cubic m / h cubic in / s cubic ft / s cubic ft / h USG / s USG / h
cubic m / s 1 60000 3600 61024 35.315 127133 264.17 951019
l / min 1.6667e-05 1 0.06 0.98322 1699.0 0.47195 227.12 0.063090
cubic m / h 0.00027778 16.667 1 0.058993 101.94 0.028317 13.627 0.0037854
cubic in / s 1.6387e-05 1.0171 16.951 1 1728 0.48 231 0.064167
cubic ft / s 0.028317 0.00058858 0.0098096 0.00057870 1 0.00027778 0.13368 3.7133e-05
cubic ft / h 7.8658e-06 2.1189 35.315 2.0833 3600 1 481.25 0.13368
USG / s 0.0037854 0.0044029 0.073381 0.0043290 7.4805 0.0020779 1 0.00027778
USG / h 1.0515e-06 15.850 264.17 15.584 26930 7.4805 3600 1
Values are rounded to five meaning digits where not accurate.

Temperature
Below are the most common temperature conversion for-
mulas:
°C = value[K] - 273.15
°C = 5 / 9 * (value[F] - 32)
K = value[°C] + 273.15
K = 5 / 9 * (value[F] - 32) + 273.15
F = 9 / 5 * value[°C] + 32
F = 9 / 5 * (value[K] - 273.15) + 32
Prefix
Below are the most common prefix multipliers:
T = Tera = 1 000 000 000 000 times
G = Giga = 1 000 000 000 times
M = Mega = 1 000 000 times
k = kilo = 1 000 times
m = milli = divided by 1 000
m = micro = divided by 1 000 000
n = nano = divided by 1 000 000 000

Marine Project Guide W20 - 1/2002 141

 22. ANNEX

22.3.Collection of drawing
symbols used in drawings

142 Marine Project Guide W20 - 1/2002

 22. ANNEX

22.4. Notes for the CD-ROM

Hardware requirements:
• CD-ROM drive
Software requirements:
• Adobe Acrobat Reader 4.0 or later or other application
capable of reading the files
• AutoCAD xx or later or other application capable of
reading the files
The files are organized in folders according to the engine
types.

Marine Project Guide W20 - 1/2002 143