ASIAN INSTITUTE OF MARITIME STUDIES

Introduction
The name Tug Boats gives a fair idea about the size and task of the vessel being

discussed. These are relatively smaller but very powerful for their size. These are primarily

used to tug or pull vessels that cannot move by themselves like disabled ships, oil

platforms and barges or those that should not move like a big or loaded ship in a narrow

canal or a crowded harbor. In addition to these, tug boats are also used as ice breakers

or salvage boats and as they are built with firefighting guns and monitors, they assist in

the firefighting duties especially at harbors and when required even at sea.

Tugboats are mainly divided according to their application and utility. The three

main categories in which the tugboats can be divided are: Seagoing Tugs, Escort Tugs

and Harbour Tugs.

Seagoing tugs have a wide range of applications as they are not constrained by

any port duties. Seagoing tugs perform the following tasks: (1) Seagoing tugs are

manufactured to stay away at the sea for a longer duration of time and yet retain power to

pull a vessel that is much larger in size than its own. (2) Used by environmentalist and

researchers for surveying a particular area, and for pulling offshore drilling platforms and

also for handling anchors in the offshore industry. (3) Used extensively in pulling structures

that needs to be relocated. For e.g. Partly completed ships that has to be shifted from one

port to another, pulling and erecting drilling rigs, moving ship wrecks away from the

waterways etc. and, (4) Used for averting a major disaster in case a ship has developed a

crack in the cargo hold or an accidental leakage. These tugboats are never used for

transporting purposes.

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 ASIAN INSTITUTE OF MARITIME STUDIES

Escort Tugs, this type of tugboats are used to escort huge vessels along narrow

or dangerous passages. This facilities are provided only to massive ships whose own

propulsion system is not capable of doing maneuverability in dangerous. This facility has

been introduces as a result of series of accidents in the past that had lead adverse effects

on both marine and human life. Escort tugs are small and sturdy vessels that generally

operate in the confined water. They have high maneuverability power and often

have azimuthing thrusters.

Harbor Tugs are multiple-utility boats that are used in ports and inland water

ways for assisting and towing vessels in and out of the ports. They are also used for

pulling barges used for carrying goods in inland water ways or along the ports. Harbor tugs

assist seagoing tugs when the later are pulling a very heavy object. The harbor tugs have

the highest maneuverability as they have to pull and tow huge ships within small area.

Apart from that, harbor tugs are used in firefighting and keeping ports free from ice in

winter season. They have a capacity to generate a towing force at zero velocity. They are

also equipped with firefighting arrangements and equipment for fighting marine pollution.

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 ASIAN INSTITUTE OF MARITIME STUDIES

History
Tugboat, small, powerful watercraft designed to perform a variety of functions,

especially to tow or push barges and large ships. In 1736 Jonathan Hulls of

Gloucestershire, Eng., patented a boat to be powered by a Newcomen steam engine to

move large vessels in and out of harbours. The first tugboat actually built was

the Charlotte Dundas, powered by a Watt engine and paddle wheel and used on the Forth

and Clyde Canal in Scotland. Screw propulsion for tugboats was introduced in the United

States about 1850, the diesel engine about 50 years later. Tugs are still indispensable in

berthing large ships. Oceangoing tugs are used for salvage missions.

Mission

To assists the merchant vessel in entering the port of Davao and to accompany

the dredger from port of Davao to port of Zamboanga vice versa. It has a fire fighting to

serve those who needs assistance in needs of emergency.

Statement of the Problem

The designer is assigned to design a push/pull/service harbour tug that will be

used in assisting large vessel. The tug is required to have 70 tons bollard pull and have

good maneuverability. Also, this tug must maximize its usefulness and earning power.

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 ASIAN INSTITUTE OF MARITIME STUDIES

OWNER’S REQUIREMENTS
OWNER'S REQUIREMENT

TYPE OF VESSEL: PUSH/PULL/SERVICE HARBOUR TUG

BOLLARD PULL: 70 TONNES

FREE RUNNING SPEED: 12 KNOTS

SERVICE SPEED: 7 KNOTS

PROPULSION: AZIMUTH PROPELLER

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 1

PARENTSHIP

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 1 : PARENTSHIP

Particulars VESSEL A1 VESSEL B1 VESSEL C2 AVERAGE

L.O.A 31.62 m 31.62 m 38 m 34 m
L.B.P 30.5 m 30.5 m 32.3 m 31 m
Breadth 12 m 12 m 10 m 11 m
Depth 5.2 m 5.2 m 4.6 m 5 m
draft 4.26 m 4.29 m 3.4 m 4 m
Deadweight 274.81 tonnes 274.81 m 411.481 m 320 m
Displacement 927.8 tonnes 934.4 tonnes 652.88 tonnes 838 tonnes
Lightship 653 tonnes 586 tonnes 241.399 tonnes 493 tonnes
Bollard Pull 73 tonnes 72 tonnes 64 tonnes 70 tonnes
Speed 13 knots 13 knots 13 knots 13 knots
ME (Kw) 1838 kW 1838 kW 1920 kW 1865 kW
No. of
4 blades 4 blades 4 blades 4 blades
Propeller
Propulsion 2 x Z-Peller - 2 x Z-Peller - KST200ZF - B1 -
Unit ZP41 ZP41 REXPELLER

Ratio and Parameters

VESSEL A VESSEL B VESSEL C AVERAGE
L/B 2.54 2.54 3.23 2.77
L/D 5.87 5.87 7.02 6.25
L/d 7.16 7.11 9.5 7.92
B/d 2.82 2.80 2.94 2.85
d/B 0.36 0.36 0.34 0.35
d/D 0.82 0.83 0.74 0.79

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 2

DETERMINATION
OF PARTICULARS

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 2: DETERMINATION OF THE PARTICULARS

SUMMARY OF THE PARENTSHIP:

Particulars Value
LOA 34 m
LBP 31 m RATIO AND PARAMETERS
BREADTH 11 m AVERAGE
DEPTH 5m L/B 2.77
DRAFT 4m L/D 6.25
DISPLACEMENT 838 tonnes L/d 7.92
DEADWEIGHT 320 tonnes B/d 2.85
LIGHTSHIP 493 tonnes d/B 0.35
BOLLARD PULL 70 tonnes d/D 0.79
SPEED 13 knots
MAIN ENGINE (Kw) 3730 kW

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 ASIAN INSTITUTE OF MARITIME STUDIES

CUBEROOT METHOD
•BLOCK COEFFICIENT
Reference: Elements of Ship Design by R. Munro - Smith, p 14

This coefficient, Cb, is the ratio of the volume of displacement in m3 to a given

waterline and the volume of the circumscribing block of constant rectangular
section having the same length (L), breadth (B) and draught (d) as the ship.

Cb=

where:
Δ- Displacement of the ship

L- Length (LBP)
B- Breadth molded
838 d- draft
1398.10 ρ- density, 1.025 tonnes/m 3

Cb= 0.599

•DEADWEIGHT COEFFICIENT
Reference: Elements of Ship Design by R. Munro - Smith, p 14

The ratio of the deadweight at the load draught to the corresponding

displacement is termed the deadweight coefficient, Cd.

Cd= DEADWEIGHT
DISPLACEMENT

320 tonnes
838 tonnes

Cd= 0.382

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 ASIAN INSTITUTE OF MARITIME STUDIES

•CUBEROOT METHOD
Reference: Ship Design and Performance for Masters and Mates by Dr C.B. Barras, p. 5
From the information on ships already built and in service, the Naval archihtect
can decide upon the relations of L/B and B/d for the new ship. Knowing these
values he can have a good first attempt at the Main Dimensions for the new
vessel. He can used the following formula:

(DEADWEIGHT)(L/B)²(B/D)
LBP= ( (ρ)(Cb) (Cd) )
where: L: Length (LBP)
L/B: Length -Breadth Ratio
B/d: Breadth-draft Ratio
ρ: Density of seawater (1.025 tonnes/m3)
Cb: Block Coefficient
Cd: Deadweight Coefficient

2
320 x 2.77 x 2.85
( 0.599 x 1.025 x 0.382 )

6997.6848
( 0.2346 )

LBP= 31 meters

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 ASIAN INSTITUTE OF MARITIME STUDIES

To get the remaining particulars:

• BREADTH MOULDED
L/B= 2.77
where:
B= L / 2.77 L= LBP, 31.01

31.01 / 2.77

B= 11.195 , 11 meters

• DEPTH MOULDED
L/D= 6.25
where:
D= L / 6.25 L= LBP, 31.01

31.01 / 6.25

D= 4.9616 , 5 meters

• DRAFT
L/d= 7.92
where:
D= L / 7.92 L= LBP, 31.01

31.01 / 7.92

D= 3.9154 , 4 meters

Note: Derived from the design ratios of the averaged particulars of the vessel to be designed.

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 ASIAN INSTITUTE OF MARITIME STUDIES

To check the gathered particulars, I will use the proportions of tugboats from Table 1 of
Modern Tug Design:

• BREADTH MOULDED
L/B= 2.7 to 3.7

= L / B

= 31.00 / 11.195

L/B = 2.8

• DEPTH MOULDED
B/d = 2.3 to 3.6
where:
= B / d L= LBP, 0.00

= 11.195 / 4.96

B/d = 2.3

• DRAFT
L/D = 5 to 30
where:
= L / D L= LBP, 0.00

31.00 / 3.915

D= 8

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 ASIAN INSTITUTE OF MARITIME STUDIES

PARTICULARS OF THE VESSEL TO BE DESIGNED

PARTICULARS VALUE
L.B.P. 31 METERS
BREADTH MOULDED 11 METERS
DEPTH MOULDED 5 METERS
DRAFT 4 METERS

*note: I round my particulars to whole number

SPEED COMPUTATION
• SERVICE SPEED (Vs)
Vs where:
= 0.60 TO 0.70
√L 0.60 to 0.70 adopt to 0.65
L - LBP in feet 101.744
Vs
= 0.65
√101.74

Vs = 0.65 x 10.0868

= 6.55643

Vs = 7 Knots

• FREE RUNNING SPEED (Vk)

Vk where:
= 1.1 TO 1.4
√L 1.1 to 1.4 adopt to 1.20
101.744
L - LBP in feet
Vk
= 1.2
√101.74

Vk = 1.2 x 10.0868

= 12.1042

Vk = 12 Knots

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 ASIAN INSTITUTE OF MARITIME STUDIES

• BLOCK COEFFICIENT (FOR TUGBOAT)

RANGES 0.45 TO 0.55

Vk
Cb = 1.08 -
2 √L

where: L - LBP in feet

12 101.68 ft (31 m)
= 1.08 -
2 √101.68 vk - free running speed
12 knots

= 1.08 - 0.595

Cb = 0.49

• VOLUME OF DISPLACEMENT (s )

s= LBP x B x d x Cb where: LBP - 31 m

B - 11
= 31m x 11m x 4m x 0.49 d-4
Cb - 0.49

s= 668.36 m 3

• DISPLACEMENT (Δ )

Δ= LBP x B x d x Cb x ρ where: LBP - 31 m

B - 11
3
= 31m x 11m x 4m x 0.49 x 1.025 tons/m d-4
Cb - 0.49
ρ - 1.025 tons
Δ= 685.069 tons
m3

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 3

LINES DRAWING
PLAN

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 ASIAN INSTITUTE OF MARITIME STUDIES

INTRODUCTION TO LINES DRAWING PLAN

A ship’s hull is three dimensional and, as is usually the case, it is assumed here to

be symmetrical about its middle line plane.

The shape is defined by its intersections with three mutually orthogonal planes.

The intersections with horizontal planes, known as waterplanes whether below or above

water, are known as water lines. Those with the athwartships planes define the transverse

sections of the hull and planes parallel to the middle line plane lead to what are termed

bow and buttock lines.

The external hull shape can be defined by the distances of the hull from the

centerline plane at each transverse section and waterplane. In tabular form these are

known as a table of offsets.

A set of lines consists essentially of three plans of view namely the elevation or the

profile of vessel, generally known as half breadth plan and the set of transverse section

Known as body plan and Naval architects use different methods for hull construction

keeping in mind the purpose and type of ship.

The form of a ship’s hull drawn to scale is called the lines drawing. Lines’ drawing

is the first step the ship design and is the foundation on which other ship design parameters

and plans will originate.

For an instance, the general arrangement plan, the lines drawing will provide the

amount of space that the naval architect can use to determine the arrangements of

machineries, equipments, cargoes and etc.

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 ASIAN INSTITUTE OF MARITIME STUDIES

Lines Drawing Process

The first step of the lines drawing is to draw a rectangular box with the length of

your vessel. This will be your size of your propose vessel and the existence of the lines

drawing. This body plans show the shape of the vessel from your lines drawing Project

lines from half Breadth plan to body plan then project body plan to Buttock line. The body

plan of ship design is to guide the designers for the desired displacement and Position of

LCB can be derived from the basic form by lifting sections for the new ship Design from

the basis at a revised spacing from the end. To visualize the projection of body plan, we

must imagine the ship’s hull is obtained at each cut when resulting curve or projected to

the body plan

Body plan (sectional)

To visualize the projection knows as body plan, we must imagine the ship’s hull at

transverse in several place. The shape of transverse plane intersection of the full is

obtained at each cut; when the resulting curves are project in to the body plan they show

the changing shape of transverse section of the hull

Half-breadth plan (Plan View)

To visualize the half-breadth plan, we must imagine the ship cut horizontally in

sever; place. The cuts are designated as “waterlines”, although the ship could not possibly

float at many of these lines. The base plane which serves as the point of origin for waterline

is usually horizontal plane that the coincides which the top of the keel.

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 4

SECTIONAL AREA
COMPUTATION

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 4: SECTIONAL AREA

PARTICULARS:
V ALUE
LENGTH OV ERALL 32.52 METERS
L.B.P. 31 METERS
BREADTH MOULDED 11 METERS
DEPTH MOULDED 5 METERS
DRAFT 4 METERS
DISPLACEMENT 685.0 TONNES
V OL. OF DISPLACEMENT 668.0 TONNES
STATION SPACING 3.1 METERS
WATERLINE SPACING 0.5 METERS

TABLE OF OFFSETS (FP TO 5)

STATIONS
FP 0.5 1 1.5 2 3 4 5
WL 4 0.000 2.458 3.214 3.780 4.269 4.976 5.337 5.446
WL 3.5 0.000 2.234 3.087 3.657 4.160 4.881 5.257 5.366
WL 3 0.000 1.689 2.736 3.439 4.061 4.796 5.178 5.287
WL 2.5 0.000 0.972 2.212 3.094 3.694 4.616 5.098 5.214
WL 2 0.000 0.209 1.576 2.544 3.308 4.291 4.796 4.940
WL 1.5 0.000 0.000 0.838 1.812 2.643 3.944 4.482 4.637
WL 1 0.000 0.000 0.000 0.924 1.662 2.814 3.562 3.919
WL 0.5 0.000 0.000 0.000 0.000 0.597 1.485 2.099 2.355
WL 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
TABLE OF OFFSETS (FP TO 5)
STATIONS
5 6 7 8 8.5 9 9.5 AP
WL 4 5.446 5.376 5.282 5.120 4.959 4.729 4.477 4.228
WL 3.5 5.366 5.307 5.192 4.990 4.795 4.456 3.358 0.000
WL 3 5.287 5.239 5.116 4.740 4.401 2.206 0.000 0.000
WL 2.5 5.214 5.170 4.867 3.285 0.551 0.000 0.000 0.000
WL 2 4.940 4.864 4.436 0.000 0.000 0.000 0.000 0.000
WL 1.5 4.637 4.558 2.011 0.000 0.000 0.000 0.000 0.000
WL 1 3.919 3.302 0.000 0.000 0.000 0.000 0.000 0.000
WL 0.5 2.355 1.410 0.000 0.000 0.000 0.000 0.000 0.000
WL 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

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 ASIAN INSTITUTE OF MARITIME STUDIES

STATION AND WATERLINE ORDINATES

STATION FP STATION 0.5

WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 0 0 4 1 2.458 2.458
3.5 4 0 0 3.5 4 2.234 8.936
3 2 0 0 3 2 1.689 3.378
2.5 4 0 0 2.5 4 0.972 3.888
2 2 0 0 2 2 0.209 0.418
1.5 4 0 0 1.5 4 0 0
1 2 0 0 1 2 0 0
0.5 4 0 0 0.5 4 0 0
0 1 0 0 0 1 0 0
∑ f(A) 0 ∑ f(A) 19.078
79

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 0 1/3 x 0.5 x 19.078
Area= 0 Area= 3.180

STATION 1 STATION 1.5

WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 3.214 3.214 4 1 3.780 3.78

3.5 4 3.087 12.348 3.5 4 3.657 14.628
3 2 2.736 5.472 3 2 3.439 6.878
2.5 4 2.212 8.848 2.5 4 3.094 12.376
2 2 1.576 3.152 2 2 2.544 5.088
1.5 4 0.838 3.352 1.5 4 1.812 7.248
1 2 0 0 1 2 0.924 1.848
0.5 4 0 0 0.5 4 0 0
0 1 0 0 0 1 0 0
∑ f(A) 36.386 ∑ f(A) 51.846

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 36.386 1/3 x 0.5 x 51.846
Area= 6.064 Area= 8.641

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 ASIAN INSTITUTE OF MARITIME STUDIES

STATION AND WATERLINE ORDINATES

STATION 2 STATION 3
WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 4.269 4.269 4 1 4.976 4.976

3.5 4 4.160 16.64 3.5 4 4.881 19.524
3 2 4.061 8.122 3 2 4.796 9.592
2.5 4 3.694 14.776 2.5 4 4.616 18.464
2 2 3.308 6.616 2 2 4.291 8.582
1.5 4 2.643 10.572 1.5 4 3.944 15.776
1 2 1.662 3.324 1 2 2.814 5.628
0.5 4 0.597 2.388 0.5 4 1.485 5.94
0 1 0 0 0 1 0 0
∑ f(A) 66.707 ∑ f(A) 88.482

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 66.707 1/3 x 0.5 x 88.482
Area= 11.12 Area= 14.75

STATION 4 STATION 5
WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 5.337 5.337 4 1 5.446 5.446

3.5 4 5.257 21.028 3.5 4 5.366 21.464
3 2 5.178 10.356 3 2 5.287 10.574
2.5 4 5.098 20.392 2.5 4 5.214 20.856
2 2 4.796 9.592 2 2 4.940 9.88
1.5 4 4.482 17.928 1.5 4 4.637 18.548
1 2 3.562 7.124 1 2 3.919 7.838
0.5 4 2.099 8.396 0.5 4 2.355 9.42
0 1 0 0 0 1 0 0
∑ f(A) 100.153 ∑ f(A) 104.026

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 100.153 1/3 x 0.5 x 104.026
Area= 16.69 Area= 17.34

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 ASIAN INSTITUTE OF MARITIME STUDIES

STATION AND WATERLINE ORDINATES

STATION 6 STATION 7
WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 5.376 4.976 4 1 5.282 4.882

3.5 4 5.307 20.828 3.5 4 5.192 20.368
3 2 5.239 10.078 3 2 5.116 9.832
2.5 4 5.170 20.28 2.5 4 4.867 19.068
2 2 4.864 9.328 2 2 4.436 8.472
1.5 4 4.558 17.832 1.5 4 2.011 7.644
1 2 3.302 6.204 1 2 0 0
0.5 4 1.410 5.24 0.5 4 0 0
0 1 0 0 0 1 0 0
∑ f(A) 94.766 ∑ f(A) 70.266

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 94.766 ` 70.266
Area= 15.79 Area= 11.71

STATION 8 STATION 8.5

WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 5.120 4.72 4 1 4.959 4.959

3.5 4 4.990 19.56 3.5 4 4.795 19.18
3 2 4.740 9.18 3 2 4.401 8.802
2.5 4 3.285 12.84 2.5 4 0.551 2.204
2 2 0 0 2 2 0 0
1.5 4 0 0 1.5 4 0 0
1 2 0 0 1 2 0 0
0.5 4 0 0 0.5 4 0 0
0 1 0 0 0 1 0 0
∑ f(A) 46.3 ∑ f(A) 35.145

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 46.3 1/3 x 0.5 x 35.145
Area= 7.717 Area= 5.858

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 ASIAN INSTITUTE OF MARITIME STUDIES

STATION AND WATERLINE ORDINATES

STATION 9 STATION 9.5

WATERLINE SM ORDINATES f(A) WATERLINE SM ORDINATES f(A)

4 1 4.729 4.729 4 1 4.477 4.477

3.5 4 4.456 17.824 3.5 4 3.358 13.432
3 2 2.206 4.412 3 2 0 0
2.5 4 0 0 2.5 4 0 0
2 2 0 0 2 2 0 0
1.5 4 0 0 1.5 4 0 0
1 2 0 0 1 2 0 0
0.5 4 0 0 0.5 4 0 0
0 1 0 0 0 1 0 0
∑ f(A) 26.965 ∑ f(A) 17.909

Area= 1/3 x S x ∑ f(A) Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 26.965 1/3 x 0.5 x 17.909
Area= 4.494 Area= 2.985

STATION AP
WATERLINE SM ORDINATES f(A)

4 1 4.228 4.228
3.5 4 0 0
3 2 0 0
2.5 4 0 0
2 2 0 0
1.5 4 0 0
1 2 0 0
0.5 4 0 0
0 1 0 0
∑ f(A) 4.228

Area= 1/3 x S x ∑ f(A)

1/3 x 0.5 x 4.228
Area= 0.705

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 ASIAN INSTITUTE OF MARITIME STUDIES

DISPLACEMENT BASED ON SECTIONAL AREA

STATION AREA SM F(V)

FP 0 0.5 0.000
0.5 3.180 2 6.359
1 6.064 1 6.064
1.5 8.641 2 17.282
2 11.118 1.5 16.677
3 14.747 4 58.988
4 16.692 2 33.384
5 17.338 4 69.351
6 15.794 2 31.589
7 11.711 4 46.844
8 7.717 1.5 11.575
8.5 5.858 2 11.715
9 4.494 1 4.494
9.5 2.985 2 5.970
AP 0.705 0.5 0.352
∑ f(V) 320.644

VOLUME OF DISPLACEMENT = ∑ f(V) x Station Spacing x 2 / 3

320.644 x 3.1 x 2 / 3

s= 662.7 m3

DISPLACEMENT = V OLUME OF DISPLACEMENT * 1.025

662.7 x 1.025

Δ= 679.2 TONNES

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 5

HYDROSTATIC
COMPUTATION

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 ASIAN INSTITUTE OF MARITIME STUDIES

INTRODUCTION TO HYDROSTATIC COMPUTATION

Ship Hydrostatics and Stability is a complete guide to understanding ship

hydrostatics in ship design and ship performance, taking you from first principles through

basic and applied theory to contemporary mathematical techniques for hydrostatic

modeling and analysis. Real life examples of the practical application of hydrostatics are

used to explain the theory and calculations using Excel.

The purpose of hydrostatic curves is to show the different statical characteristic

of vessel on water. It is very useful as a guide of chief mate

Hydrostatics is the branch of fluid mechanics that studies fluids at rest. It embraces the

conditions to which the vessel is subjected to while at rest in water and its ability to remain

afloat. This involves computing buoyancy and other hydrostatic properties, such as trim

and stability.

The purpose of hydrostatic curve is to show the different statically characteristics

of vessel in the water. It is very useful as a guide to chief-mate during loading and

unloading cargo operations.

Using hydrostatic calculations, you will get the values needed for plotting the

sectional area and bonjean curves. This part will also determine if block coefficient is

applicable for the plan of the proposed vessel.

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 ASIAN INSTITUTE OF MARITIME STUDIES

PART 5 : HYDROSTATIC CALCULATIONS

PARTICULARS:
VALUE
LBP 31 Meters
BREADTH 11 Meters
DEPTH 5 Meters
DRAFT 4 Meters
WATERLINE SPACING 0.5 Meter
STATION SPACING 3.1 Meters
DIVISOR 180

TABLE OF OFFSETS
STATION WL 0 WL 0.5 WL 1 WL 1.5 WL 2 WL 2.5 WL 3 WL 3.5 WL 4

FP 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

0.5 0.000 0.000 0.000 0.000 0.209 0.972 1.689 2.234 2.458

1.0 0.000 0.000 0.000 0.838 1.576 2.212 2.736 3.087 3.214

1.5 0.000 0.000 0.924 1.812 2.544 3.094 3.439 3.657 3.780

2 0.000 0.597 1.662 2.643 3.308 3.694 4.061 4.160 4.269

3 0.000 1.485 2.814 3.944 4.291 4.616 4.796 4.881 4.976

4 0.000 2.099 3.562 4.482 4.796 5.098 5.178 5.257 5.337

5 0.000 2.355 3.919 4.637 4.940 5.214 5.287 5.366 5.446

6 0.000 1.410 3.302 4.558 4.864 5.170 5.239 5.307 5.376

7 0.000 0.000 0.000 2.011 4.436 4.867 5.116 5.192 5.282

8 0.000 0.000 0.000 0.000 0.000 3.285 4.740 4.990 5.120

8.5 0.000 0.000 0.000 0.000 0.000 0.551 4.401 4.795 4.959

9 0.000 0.000 0.000 0.000 0.000 0.000 2.206 4.456 4.729

9.5 0.000 0.000 0.000 0.000 0.000 0.000 0.000 3.358 4.477

AP 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 4.228

Page | 27
 ASIAN INSTITUTE OF MARITIME STUDIES

DISPLACEMENT AND CENTER

DISPL. FROM WL 0 UP TO W.L. 1
HALF- BREADTH Section

STA SMs W.L. 0.00 W.L. 0.5 W.L. 1 F(A)s F(V)s LA F(LM)

SM 1 SM 4 SM 1 Area
0.000 0.000 0.000
FP 0.50 0.000 0.000 0.000 0.000 0.000 5 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.50 2.0 0.000 0.000 0.000 0.000 0.000 4.5 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
1.00 1.0 0.000 0.000 0.000 0.000 0.000 4 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.924
1.50 2.00 0.000 0.000 1.848 0.924 1.848 3.5 6.468 0.308
0.000 0.000 0.924
0.000 0.597 1.662
2 1.50 0.000 0.896 2.493 4.050 6.075 3 18.225 1.350
0.000 2.388 1.662
0.000 1.485 2.814
3 4.00 0.000 5.940 11.256 8.754 35.016 2 70.032 2.918
0.000 5.940 2.814
0.000 2.099 3.562
4 2.0 0.000 4.198 7.124 11.958 23.916 1 23.916 3.986
0.000 8.396 3.562
0.000 2.355 3.919
5 4.0 0.000 9.420 15.676 13.339 53.356 0 0.000 4.446
0.000 9.420 3.919
0.000 1.410 3.302
6 2.0 0.000 2.820 6.604 8.942 17.884 -1 -17.884 2.981
0.000 5.640 3.302
0.000 0.000 0.000
7 4.0 0.000 0.000 0.000 0.000 0.000 -2 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
8 1.5 0.000 0.000 0.000 0.000 0.000 -3 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
8.5 2.0 0.000 0.000 0.000 0.000 0.000 -3.5 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
9 1.0 0.000 0.000 0.000 0.000 0.000 -4 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
9.5 2 0.000 0.000 0.000 0.000 0.000 -4.50 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
AP 0.50 0.000 0.000 0.000 0.000 0.000 -5.00 0.000 0.000
0.000 0.000 0.000
Sum of
F(A)
0.0 23.3 45.001 F(V) 138.095 118.641 FWD
SM 1 4 1 -17.884 AFT
Sum of

F(V) 0 93.094 45.001 F(V) 138.095 100.757 DIFF

LA 0.00 0.5 1 CFwd 0.000 6.2 2xS

TOTAL F (V)
1/2F(VM) 0 46.547 45.001 276.190 624.6934 PROD.
DIVISOR
(3N3)/WL 0 C.FWD
SPA 180
1/2F(VM)x2 183.096 MEAN F(V) 1.534 624.6934 TOTAL F(LM)
C.FWD. 0

TOTAL F(VM) 183.096 0.50 WL. SPA. 3.1 STA. SPA

Page | 28
 ASIAN INSTITUTE OF MARITIME STUDIES

DISPLACEMENT AND CENTER

DISPL. FROM WL 1 UP TO W.L. 2
HALF- BREADTH Section

STA SMs W.L. 1.0 W.L. 1.5 W.L. 2 F(A)s F(V)s LA F(LM)

SM 1 SM 4 SM 1 Area
0.000 0.000 0.000
FP 0.50 0.000 0.000 0.000 0.000 0.000 5 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.209
0.50 2.0 0.000 0.000 0.418 0.209 0.418 4.5 1.881 0.070
0.000 0.000 0.209
0.000 0.838 1.576
1.00 1.0 0.000 0.838 1.576 4.928 4.928 4 19.712 1.643
0.000 3.352 1.576
0.924 1.812 2.544
1.50 2.00 1.848 3.624 5.088 10.716 21.432 3.5 75.012 3.880
0.924 7.248 2.544
1.662 2.643 3.308
2 1.50 2.493 3.965 4.962 15.542 23.313 3 69.939 6.531
1.662 10.572 3.308
2.814 3.944 4.291
3 4.00 11.256 15.776 17.164 22.881 91.524 2 183.048 10.545
2.814 15.776 4.291
3.562 4.482 4.796
4 2.0 7.124 8.964 9.592 26.286 52.572 1 52.572 12.748
3.562 17.928 4.796
3.919 4.637 4.940
5 4.0 15.676 18.548 19.760 27.407 109.628 0 0.000 13.582
3.919 18.548 4.940
3.302 4.558 4.864
6 2.0 6.604 9.116 9.728 26.398 52.796 -1 -52.796 11.780
3.302 18.232 4.864
0.000 2.011 4.436
7 4.0 0.000 8.044 17.744 12.480 49.920 -2 -99.840 4.160
0.000 8.044 4.436
0.000 0.000 0.000
8 1.5 0.000 0.000 0.000 0.000 0.000 -3 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
8.5 2.0 0.000 0.000 0.000 0.000 0.000 -3.5 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
9 1.0 0.000 0.000 0.000 0.000 0.000 -4 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
9.5 2 0.000 0.000 0.000 0.000 0.000 -4.50 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
AP 0.50 0.000 0.000 0.000 0.000 0.000 -5.00 0.000 0.000
0.000 0.000 0.000
Sum of
F(A)
45.00 68.87 86.03 F(V) 406.531 402.164 FWD
SM 1 4 1 -152.636 AFT
Sum of
F(V) 45.001 275.5 86.032 F(V) 406.531 249.528 DIFF
LA 1.00 1.5 2 CFwd 276.190 6.2 2xS
TOTAL F
1/2F(VM) 45.001 413.25 172.06 (V) 1089.252 1547.074 PROD.
DIVISOR
(3N3)/WL 624.6934 C.FWD
SPA 180
TOTAL F(LM)
MEAN F(V)
1/2F(VM)x2 1260.624 6.051 2171.767
C.FWD. 183.096

TOTAL F(VM) 1443.720 0.50 WL. SPA. 3.1 STA. SPA

Page | 29
 ASIAN INSTITUTE OF MARITIME STUDIES

DISPLACEMENT AND CENTER

DISPL. FROM WL 2 UP TO W.L. 3
HALF- BREADTH Section

STA SMs W.L. 2 W.L. 2.5 W.L. 3 F(A)s F(V)s LA F(LM)

SM 1 SM 4 SM 1 Area
0.000 0.000 0.000
FP 0.50 0.000 0.000 0.000 0.000 0.000 5 0.000 0.000
0.000 0.000 0.000
0.209 0.972 1.689
0.50 2.0 0.418 1.944 3.378 5.786 11.572 4.5 52.074 1.998
0.209 3.888 1.689
1.576 2.212 2.736
1.00 1.0 1.576 2.212 2.736 13.160 13.160 4 52.640 6.029
1.576 8.848 2.736
2.544 3.094 3.439
1.50 2.00 5.088 6.188 6.878 18.359 36.718 3.5 128.513 10.000
2.544 12.376 3.439
3.308 3.694 4.061
2 1.50 4.962 5.541 6.092 22.145 33.218 3 99.653 13.912
3.308 14.776 4.061
4.291 4.616 4.796
3 4.00 17.164 18.464 19.184 27.551 110.204 2 220.408 19.729
4.291 18.464 4.796
4.796 5.098 5.178
4 2.0 9.592 10.196 10.356 30.366 60.732 1 60.732 22.870
4.796 20.392 5.178
4.940 5.214 5.287
5 4.0 19.760 20.856 21.148 31.083 124.332 0 0.000 23.943
4.940 20.856 5.287
4.864 5.170 5.239
6 2.0 9.728 10.340 10.478 30.783 61.566 -1 -61.566 22.041
4.864 20.680 5.239
4.436 4.867 5.116
7 4.0 17.744 19.468 20.464 29.020 116.080 -2 -232.160 13.833
4.436 19.468 5.116
0.000 3.285 4.740
8 1.5 0.000 4.928 7.110 17.880 26.820 -3 -80.460 5.960
0.000 13.140 4.740
0.000 0.551 4.401
8.5 2.0 0.000 1.102 8.802 6.605 13.210 -3.5 -46.235 2.202
0.000 2.204 4.401
0.000 0.000 2.206
9 1.0 0.000 0.000 2.206 2.206 2.206 -4 -8.824 0.735
0.000 0.000 2.206
0.000 0.000 0.000
9.5 2 0.000 0.000 0.000 0.000 0.000 -4.50 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
AP 0.50 0.000 0.000 0.000 0.000 0.000 -5.00 0.000 0.000
0.000 0.000 0.000
Sum of
F(A)
86.0 101.2 118.8 F(V) 609.818 614.02 FWD
SM 1.0 4.0 1.0 -429.25 AFT
Sum of
F(V) 86.0 405.0 118.8 F(V) 609.818 184.775 DIFF
LA 2.0 2.5 3.0 CFwd 1089.252 6.2 2xS
TOTAL F
1/2F(VM) 172.1 1012.4 356.5 (V) 2308.89 1145.602 PROD.
DIVISOR
(3N3)/WL 2171.767 C.FWD
SPA 180
TOTAL
MEAN F(V)
1/2F(VM)x2 3081.887 12.827 3317.369 F(LM)
C.FWD. 1443.72

TOTAL F(VM) 4525.607 0.50 WL. SPA. 3.1 STA. SPA

Page | 30
 ASIAN INSTITUTE OF MARITIME STUDIES

DISPLACEMENT AND CENTER

DISPL. FROM WL 3 UP TO W.L. 4
HALF- BREADTH Section

STA SMs W.L. 3.0 W.L. 3.5 W.L. 4 F(A)s F(V)s LA F(LM)
SM 1 SM 4 SM 1 Area
0.000 0.000 0.000
FP 0.50 0.000 0.000 0.000 0.000 0.000 5 0.000 0.000
0.000 0.000 0.000
1.689 2.234 2.458
0.50 2.0 3.378 4.468 4.916 13.083 26.166 4.5 117.747 6.359
1.689 8.936 2.458
2.736 3.087 3.214
1.00 1.0 2.736 3.087 3.214 18.298 18.298 4 73.192 12.129
2.736 12.348 3.214
3.439 3.657 3.780
1.50 2.00 6.878 7.314 7.560 21.847 43.694 3.5 152.929 17.282
3.439 14.628 3.780
4.061 4.160 4.269
2 1.50 6.092 6.240 6.404 24.970 37.455 3 112.365 22.236
4.061 16.640 4.269
4.796 4.881 4.976
3 4.00 19.184 19.524 19.904 29.296 117.184 2 234.368 29.494
4.796 19.524 4.976
5.178 5.257 5.337
4 2.0 10.356 10.514 10.674 31.543 63.086 1 63.086 33.384
5.178 21.028 5.337
5.287 5.366 5.446
5 4.0 21.148 21.464 21.784 32.197 128.788 0 0.000 34.675
5.287 21.464 5.446
5.239 5.307 5.376
6 2.0 10.478 10.614 10.752 31.843 63.686 -1 -63.686 32.655
5.239 21.228 5.376
5.116 5.192 5.282
7 4.0 20.464 20.768 21.128 31.166 124.664 -2 -249.328 24.222
5.116 20.768 5.282
4.740 4.990 5.120
8 1.5 7.110 7.485 7.680 29.820 44.730 -3 -134.190 15.900
4.740 19.960 5.120
4.401 4.795 4.959
8.5 2.0 8.802 9.590 9.918 28.540 57.080 -3.5 -199.780 11.715
4.401 19.180 4.959
2.206 4.456 4.729
9 1.0 2.206 4.456 4.729 24.759 24.759 -4 -99.036 8.988
2.206 17.824 4.729
0.000 3.358 4.477
9.5 2 0.000 6.716 8.954 17.909 35.818 -4.50 -161.181 5.970
0.000 13.432 4.477
0.000 0.000 4.228
AP 0.50 0.000 0.000 2.114 4.228 2.114 -5.00 -10.570 1.409
0.000 0.000 4.228
Sum of
F(A)
118.832 132.240 139.731 F(V) 787.522 753.687 FWD
SM 1 4 1 -917.771 AFT
Sum of

F(V) 118.83 528.96 139.73 F(V) 787.522 -164.084 DIFF

LA 3.00 3.5 4 CFwd 2308.89 6.2 2xS
TOTAL F
1/2F(VM) 356.49 1851.4 558.92 (V) 3883.93 -1017.32 PROD.
DIVISOR
(3N3)/WL 3317.37 C.FWD
SPA 180
TOTAL
MEAN F(V)
1/2F(VM)x2 5533.553 21.577 2300.05 F(LM)
C.FWD. 4525.607

TOTAL F(VM) 10059.160 0.50 WL. SPA. 3.1 STA. SPA

Page | 31
 ASIAN INSTITUTE OF MARITIME STUDIES

MOMENTS, CENTERS, METACENTERS, AREAS, ETC.

Up to Waterplane No. 1

STA SMs B/2 F(A)s Ls F(LM) Ls F(LI)s SMs (B/2)3s F(TI)s

FP 0.50 0.000 0.000 5 0.000 5 0.000 0.50 0.000 0.000

0.50 2.0 0.000 0.000 4.5 0.000 4.5 0.000 2.00 0.000 0.000

1.00 1.0 0.000 0.000 4 0.000 4 0.000 1.00 0.000 0.000

1.50 2.00 0.924 1.848 3.5 6.468 3.5 22.638 2.00 0.789 1.578

2 1.50 1.662 2.493 3 7.479 3 22.437 1.50 4.591 6.886

3 4.00 2.814 11.256 2 22.512 2 45.024 4.00 22.283 89.132

4 2.0 3.562 7.124 1 7.124 1 7.124 2.00 45.194 90.388

5 4.0 3.919 15.676 0 0.000 0 0.000 4.00 60.190 240.761

6 2.0 3.302 6.604 -1 -6.604 -1 6.604 2.00 36.002 72.005

7 4.0 0.000 0.000 -2 0.000 -2 0.000 4.00 0.000 0.000

8 1.5 0.000 0.000 -3 0.000 -3 0.000 1.50 0.000 0.000

8.5 2.0 0.000 0.000 -3.5 0.000 -3.5 0.000 2.00 0.000 0.000

9 1.0 0.000 0.000 -4 0.000 -4 0.000 1.00 0.000 0.000

9.5 2 0.000 0.000 -4.50 0.000 -4.5 0.000 2.00 0.000 0.000

AP 0.50 0.000 0.000 -5.00 0.000 -5 0.000 0.50 0.000 0.000

F (As) 45.001 Fwd 43.583 F(LI's) 103.8270 F(TI's) 500.75

Minus Aft -6.604
NET F (LM's) 36.979

Page | 32
 ASIAN INSTITUTE OF MARITIME STUDIES

MOMENTS, CENTERS, METACENTERS, AREAS, ETC.

Up to Waterplane No. 2

STA SMs B/2 F(A)s Ls F(LM) Ls F(LI)s SMs (B/2)3s F(TI)s

FP 0.50 0.000 0.000 5 0.000 5 0.000 0.50 0.000 0.000

0.50 2.0 0.209 0.418 4.5 1.881 4.5 8.465 2.00 0.009 0.018

1.00 1.0 1.576 1.576 4 6.304 4 25.216 1.00 3.914 3.914

1.50 2.00 2.544 5.088 3.5 17.808 3.5 62.328 2.00 16.465 32.929

2 1.50 3.308 4.962 3 14.886 3 44.658 1.50 36.199 54.298

3 4.00 4.291 17.164 2 34.328 2 68.656 4.00 79.009 316.035

4 2.0 4.796 9.592 1 9.592 1 9.592 2.00 110.316 220.632

5 4.0 4.940 19.760 0 0.000 0 0.000 4.00 120.554 482.215

6 2.0 4.864 9.728 -1 -9.728 -1 9.728 2.00 115.075 230.150

7 4.0 4.436 17.744 -2 -35.488 -2 70.976 4.00 87.292 349.168

8 1.5 0.000 0.000 -3 0.000 -3 0.000 1.50 0.000 0.000

8.5 2.0 0.000 0.000 -3.5 0.000 -3.5 0.000 2.00 0.000 0.000

9 1.0 0.000 0.000 -4 0.000 -4 0.000 1.00 0.000 0.000

9.5 2 0.000 0.000 -4.50 0.000 -4.5 0.000 2.00 0.000 0.000

AP 0.50 0.000 0.000 -5.00 0.000 -5 0.000 0.50 0.000 0.000

F (As) 86.032 Fwd 84.799 F(LI's) 299.62 F(TI's) 1689.36

Minus Aft -45.216
NET F (LM's) 39.583

Page | 33
 ASIAN INSTITUTE OF MARITIME STUDIES

MOMENTS, CENTERS, METACENTERS, AREAS, ETC.

Up to Waterplane No. 3

STA SMs B/2 F(A)s Ls F(LM) Ls F(LI)s SMs (B/2)3s F(TI)s

FP 0.50 0.000 0.000 5 0.000 5 0.000 0.50 0.000 0.000

0.50 2.0 1.689 3.378 4.5 15.201 4.5 68.405 2.00 4.818 9.636

1.00 1.0 2.736 2.736 4 10.944 4 43.776 1.00 20.481 20.481

1.50 2.00 3.439 6.878 3.5 24.073 3.5 84.256 2.00 40.672 81.344

2 1.50 4.061 6.092 3 18.275 3 54.824 1.50 66.973 100.459

3 4.00 4.796 19.184 2 38.368 2 76.736 4.00 110.316 441.263

4 2.0 5.178 10.356 1 10.356 1 10.356 2.00 138.831 277.662

5 4.0 5.287 21.148 0 0.000 0 0.000 4.00 147.784 591.137

6 2.0 5.239 10.478 -1 -10.478 -1 10.478 2.00 143.795 287.591

7 4.0 5.116 20.464 -2 -40.928 -2 81.856 4.00 133.903 535.614

8 1.5 4.740 7.110 -3 -21.330 -3 63.990 1.50 106.496 159.745

8.5 2.0 4.401 8.802 -3.5 -30.807 -3.5 107.825 2.00 85.242 170.484

9 1.0 2.206 2.206 -4 -8.824 -4 35.296 1.00 10.735 10.735

9.5 2 0.000 0.000 -4.50 0.000 -4.5 0.000 2.00 0.000 0.000

AP 0.50 0.000 0.000 -5.00 0.000 -5 0.000 0.50 0.000 0.000

F (As) 118.832 Fwd 117.217 F(LI's) 637.7960 F(TI's) 2686.15

Minus Aft -112.367
NET F (LM's) 4.849

Page | 34
 ASIAN INSTITUTE OF MARITIME STUDIES

MOMENTS, CENTERS, METACENTERS, AREAS, ETC.

Up to Waterplane No. 4

STA SMs B/2 F(A)s Ls F(LM) Ls F(LI)s SMs (B/2)3s F(TI)s

FP 0.50 0.000 0.000 5 0.000 5 0.000 0.50 0.000 0.000

0.50 2.0 2.458 4.916 4.5 22.122 4.5 99.549 2.00 14.851 29.701

1.00 1.0 3.214 3.214 4 12.856 4 51.424 1.00 33.200 33.200

1.50 2.00 3.780 7.560 3.5 26.460 3.5 92.610 2.00 54.010 108.020

2 1.50 4.269 6.404 3 19.211 3 57.632 1.50 77.800 116.700

3 4.00 4.976 19.904 2 39.808 2 79.616 4.00 123.209 492.835

4 2.0 5.337 10.674 1 10.674 1 10.674 2.00 152.017 304.034

5 4.0 5.446 21.784 0 0.000 0 0.000 4.00 161.522 646.090

6 2.0 5.376 10.752 -1 -10.752 -1 10.752 2.00 155.374 310.748

7 4.0 5.282 21.128 -2 -42.256 -2 84.512 4.00 147.365 589.461

8 1.5 5.120 7.680 -3 -23.040 -3 69.120 1.50 134.218 201.327

8.5 2.0 4.959 9.918 -3.5 -34.713 -3.5 121.496 2.00 121.950 243.900

9 1.0 4.729 4.729 -4 -18.916 -4 75.664 1.00 105.757 105.757

9.5 2 4.477 8.954 -4.50 -40.293 -4.5 181.319 2.00 89.735 179.470

AP 0.50 4.228 2.114 -5.00 -10.570 -5 52.850 0.50 75.580 37.790

F (As) 139.731 Fwd 131.131 F(LI's) 987.2165 F(TI's) 3399.03

Minus Aft -180.540
NET F (LM's) -49.410

Page | 35
 COMPUTATION SHEET
Up to Waterline 0 - 1
1 LCB = F(LM) / F(V) = 624.69 / 276.19 = 2.26 M
2 VCB = F(VM) / F(V) = 183.10 / 276.19 = 0.66 M
3 VOL. OF DISPLACEMENT = MEAN F(V) x L = 1.53 x 31.00 = 47.57 M3
4 DISPLACEMENT OF S. W. = V x 1.025 = 47.57 x 1.025 = 48.76 tons
5 DISPLACEMENT OF F. W. = V x 1.000 = 47.57 1.000 = 47.57 tons
6 MIDSHIP AREA = 1/3WLS x F(A) x 2 + C.FWD = 0.17 x 13.3390 x 2.00 + 0.00 = 4.45 M2
7 AWP NO. ______
0.5 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 23.27 x 2.00 = 48.10 M2
8 AWP NO. ______
1.00 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 45.00 x 2.00 = 93.00 M2
9 T.P.C. NO. W.L. 0.5 = AWP / 97.5 = 48.10 / 97.50 = 0.49 ton
10 T.P.C. NO. W.L. 1 = AWP / 97.5 = 93.00 / 97.50 = 0.95 ton
11 BLOCK COEFFICIENT = V / (L x B x H) = 47.57 /( 31.00 x 11.00 x 1.00 )= 0.14
12 PRISMATIC COEFFICIENT = V / (L x MIDSHIP AREA) = 47.57 /( 31.00 x 4.45 )= 0.35
13 MIDSHIP COEFFICIENT = MIDSHIP AREA / (B x H) = 4.45 /( 11.00 x 1.00 = 0.40
14 WATERPLANE COEFFICIENT = AWP / (L x B) = 93.00 /( 31.00 x 11.00 = 0.27
15 C.F. about STA. 5 = NET F(LMs) / F(As) x S = ( 36.98 / 45.00 )x 3.10 = 2.55 M
3
16 IL about STA. 5 = 1/3 x S x 2 x F(LI's) = 0.33 x 29.79 x 2.00 x 103.83 = 2062.07 M4
17 IL CORRECTION = AWP x C.F. from STA 5 = 93.00 x 2.55 = 236.91 M4
18 IL OF C.F. = IL - IL CORRECTION = 2062.1 - 236.91 = 1825.16 M4
19 BML = IL of CF/ V = 1825.2 / 47.57 = 38.37 M
ASIAN INSTITUTE OF MARITIME STUDIES

20 M Tcm = S.W. DISPL. x BML / (100 x L) = 48.76 x 38.37 /( 100.00 x 31.00 )= 0.60 T
21 IT = 2/3 x S/3 x F(TI's) = 0.67 x 1.03 x 500.75 = 344.96 M4
22 BMT = IT / V = 344.96 / 47.57 = 7.25 M
23 KMT = VCB + BMT = 0.66 + 7.25 = 7.92 M
24 KML = VCB + BML = 0.66 38.37 = 39.03 M

Page | 36
25 FRESHWATER ALLOWANCE = DISPLACEMENT/4TPC = 48.76 /( 4.00 x 0.95 )= 12.78 mm
 COMPUTATION SHEET
Up to Waterline 1 - 2
1 LCB = F(LM) / F(V) = 2171.77 / 1089.25 = 1.99 M
2 VCB = F(VM) / F(V) = 1443.72 / 1089.25 = 1.33 M
3 VOL. OF DISPLACEMENT = MEAN F(V) x L = 6.05 x 31.00 = 187.59 M3
4 DISPLACEMENT OF S. W. = V x 1.025 = 187.59 x 1.025 = 192.28 tons
5 DISPLACEMENT OF F. W. = V x 1.000 = 187.59 1.000 = 187.59 tons
6 MIDSHIP AREA = 1/3WLS x F(A) x 2 + C.FWD = 0.17 x 27.4 x 2.00 + 4.446 = 13.58 M2
7 AWP NO. ______
1.5 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 68.87 x 2.00 = 142.34 M2
8 AWP NO. ______
2.00 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 86.03 x 2.00 = 177.80 M2
9 T.P.C. NO. W.L. 1.5 = AWP / 97.5 = 142.34 / 97.50 = 1.46 ton
10 T.P.C. NO. W.L. 2 = AWP / 97.5 = 177.80 / 97.50 = 1.82 ton
11 BLOCK COEFFICIENT = V / (L x B x H) = 187.59 /( 31.00 x 11.00 x 2.00 )= 0.28
12 PRISMATIC COEFFICIENT = V / (L x MIDSHIP AREA) = 187.59 /( 31.00 x 13.58 )= 0.45
13 MIDSHIP COEFFICIENT = MIDSHIP AREA / (B x H) = 13.58 /( 11.00 x 2.00 = 0.62
14 WATERPLANE COEFFICIENT = AWP / (L x B) = 177.80 /( 31.00 x 11.00 = 0.52
15 C.F. about STA. 5 = NET F(LMs) / F(As) x S = ( 39.58 / 86.03 )x 3.10 = 1.43 M
3
16 IL about STA. 5 = 1/3 x S x 2 x F(LI's) = 0.33 x 29.79 x 2.00 x 299.62 = 5950.62 M4
17 IL CORRECTION = AWP x C.F. from STA 5 = 177.80 x 1.43 = 253.60 M4
18 IL OF C.F. = IL - IL CORRECTION = 5950.62 - 253.60 = 5697.03 M4
19 BML = IL of CF/ V = 5697.03 / 187.59 = 30.37 M
20 M Tcm = S.W. DISPL. x BML / (100 x L) = 192.28 x 30.37 /( 100.00 x 31.00 )= 1.88 T
ASIAN INSTITUTE OF MARITIME STUDIES

21 IT = 2/3 x S/3 x F(TI's) = 0.67 x 1.03 x 1689.36 = 1163.78 M4

22 BMT = IT / V = 1163.78 / 187.59 = 6.20 M
23 KMT = VCB + BMT = 1.33 + 6.20 = 7.53 M
24 KML = VCB + BML = 1.33 30.37 = 31.69 M

Page | 37
25 FRESHWATER ALLOWANCE = DISPLACEMENT/4TPC = 192.28 /( 4.00 x 1.82 )= 26.36 mm
 COMPUTATION SHEET
Up to Waterline 2 - 3
1 LCB = F(LM) / F(V) = 3317.37 / 2308.89 = 1.44 M
2 VCB = F(VM) / F(V) = 4525.61 / 2308.89 = 1.96 M
3 VOL. OF DISPLACEMENT = MEAN F(V) x L = 12.83 x 31.00 = 397.64 M3
4 DISPLACEMENT OF S. W. = V x 1.025 = 397.64 x 1.025 = 407.58 tons
5 DISPLACEMENT OF F. W. = V x 1.000 = 397.64 1.000 = 397.64 tons
6 MIDSHIP AREA = 1/3WLS x F(A) x 2 + C.FWD = 0.17 x 31.1 x 2.00 + 13.58 = 23.94 M2
7 AWP NO. ______
2.50 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 101.24 x 2.00 = 209.23 M2
8 AWP NO. ______
3.00 = 1/3 S x F(A) x 2 = 0.33 X 3.10 x 118.83 x 2.00 = 245.59 M2
9 T.P.C. NO. W.L. 2.5 = AWP / 97.5 = 209.23 / 97.50 = 2.15 ton
10 T.P.C. NO. W.L. 3 = AWP / 97.5 = 245.59 / 97.50 = 2.52 ton
11 BLOCK COEFFICIENT = V / (L x B x H) = 397.64 /( 31.00 x 11.00 x 3.00 )= 0.39
12 PRISMATIC COEFFICIENT = V / (L x MIDSHIP AREA) = 397.64 /( 31.00 x 23.94 )= 0.54
13 MIDSHIP COEFFICIENT = MIDSHIP AREA / (B x H) = 23.94 /( 11.00 x 3.00 = 0.73
14 WATERPLANE COEFFICIENT = AWP / (L x B) = 245.59 /( 31.00 x 11.00 = 0.72
15 C.F. about STA. 5 = NET F(LMs) / F(As) x S = ( 4.85 / 118.83 )x 3.10 = 0.13 M
3
16 IL about STA. 5 = 1/3 x S x 2 x F(LI's) = 0.33 x 29.79 x 2.00 x 637.80 = 12667.05 M4
17 IL CORRECTION = AWP x C.F. from STA 5 = 245.59 x 0.13 = 31.07 M4
18 IL OF C.F. = IL - IL CORRECTION = 12667.05 - 31.07 = 12635.98 M4
19 BML = IL of CF/ V = 12635.98 / 397.64 = 31.78 M
20 M Tcm = S.W. DISPL. x BML / (100 x L) = 407.58 x 31.78 /( 100.00 x 31.00 )= 4.18 T
ASIAN INSTITUTE OF MARITIME STUDIES

21 IT = 2/3 x S/3 x F(TI's) = 0.67 x 1.03 x 2686.15 = 1850.46 M4

22 BMT = IT / V = 1850.46 / 397.64 = 4.65 M
23 KMT = VCB + BMT = 1.96 + 4.65 = 6.61 M
24 KML = VCB + BML = 1.96 31.78 = 33.74 M
25 FRESHWATER ALLOWANCE = DISPLACEMENT/4TPC = 407.58 /( 4.00 x 2.52 )= 40.45 mm

Page | 38
 COMPUTATION SHEET
Up to Waterline 3 - 4
1 LCB = F(LM) / F(V) = 2300.05 / 3883.93 = 0.59 M
2 VCB = F(VM) / F(V) = 10059.16 / 3883.93 = 2.59 M
3 VOL. OF DISPLACEMENT = MEAN F(V) x L = 21.58 x 31.00 = 668.90 M3
4 DISPLACEMENT OF S. W. = V x 1.025 = 668.90 x 1.025 = 685.62 tons
5 DISPLACEMENT OF F. W. = V x 1.000 = 668.90 1.000 = 668.90 tons
6 MIDSHIP AREA = 1/3WLS x F(A) x 2 + C.FWD = 0.17 x 32.2 x 2.00 + 23.94 = 34.68 M2
7 AWP NO. ______
3.50 = 1/3 S x F(A) x 2 = 0.33 x 3.10 x 132.24 x 2.00 = 273.30 M2
8 AWP NO. ______
4.00 = 1/3 S x F(A) x 2 = 0.33 x 3.10 x 139.73 x 2.00 = 288.78 M2
9 T.P.C. NO. W.L. 3.5 = AWP / 97.5 = 273.30 / 97.50 = 2.80 ton
10 T.P.C. NO. W.L. 4 = AWP / 97.5 = 288.78 / 97.50 = 2.96 ton
11 BLOCK COEFFICIENT = V / (L x B x H) = 668.90 /( 31.00 x 11.00 x 4.00 )= 0.490
12 PRISMATIC COEFFICIENT = V / (L x MIDSHIP AREA) = 668.90 /( 31.00 x 34.68 )= 0.622
13 MIDSHIP COEFFICIENT = MIDSHIP AREA / (B x H) = 34.68 /( 11.00 x 4.00 = 0.788
14 WATERPLANE COEFFICIENT = AWP / (L x B) = 288.78 /( 31.00 x 11.00 = 0.847
15 C.F. about STA. 5 = NET F(LMs) / F(As) x S = ( -49.41 / 139.73 )x 3.10 = -1.10 M
3
16 IL about STA. 5 = 1/3 x S x 2 x F(LI's) = 0.33 x 29.79 x 2.00 x 987.22 = 19606.78 M4
17 IL CORRECTION = AWP x C.F. from STA 5 = 288.78 x -1.10 = -316.55 M4
18 IL OF C.F. = IL - IL CORRECTION = 19606.78 - -316.55 = 19923.33 M4
19 BML = IL of CF/ V = 19923.33 / 668.90 = 29.79 M
20 M Tcm = S.W. DISPL. x BML / (100 x L) = 685.62 x 29.79 /( 100.00 x 31.00 )= 6.59 T
ASIAN INSTITUTE OF MARITIME STUDIES

21 IT = 2/3 x S/3 x F(TI's) = 0.67 x 1.03 x 3399.03 = 2341.55 M4

22 BMT = IT / V = 2341.55 / 668.90 = 3.50 M
23 KMT = VCB + BMT = 2.59 + 3.50 = 6.09 M
24 KML = VCB + BML = 2.59 29.79 = 32.38 M
25 FRESHWATER ALLOWANCE = DISPLACEMENT/4TPC = 685.62 /( 4.00 x 2.96 )= 57.87 mm

Page | 39
 SUMMARY
ITEM DRAFTS IN METER
HYDROSTATIC PARTICULARS
NO 1 2 3 4
1 FRESHWATER DISPLACEMENT in MT 47.57 187.59 397.64 668.90
2 SALTWATER DISPLACEMENT in MT 48.76 192.28 407.58 685.62
3 BLOCK COEFFICIENT, Cb 0.14 0.28 0.39 0.49
4 MIDSHIP COEFFICIENT, Cm 0.40 0.62 0.73 0.79
5 WATERPLANE COEFFICIENT, Cwp 0.27 0.52 0.72 0.85
6 PRISMATIC COEFFICIENT, Cp 0.35 0.45 0.54 0.62
7 TONNES PER CENTIMETER IMMERSION, TP cm 0.95 1.82 2.52 2.96
8 MOMENT TRIM BY 1 CENTIMETER, MT cm 0.60 1.88 4.18 6.59
9 TRANSVERSE METACENTER FROM CENTER OF BOUYANCY, BMT in M 7.25 6.20 4.65 3.50
10 TRANSVERSE METACENTRIC HEIGHT ABOVE KEEL, KMT in M 7.92 7.53 6.61 6.09
11 LONGITUDINAL METACENTER FROM CENTER OF BOUYANCY, BML in M 38.37 30.37 31.78 29.79
12 LONGITUDINAL METACENTRIC HEIGHT ABOVE KEEL, KML in M 39.03 31.69 33.74 32.38
ASIAN INSTITUTE OF MARITIME STUDIES

13 LONGITUDINAL CENTER OF BOUYANCY, LCB in M 2.26 1.99 1.44 0.59

14 VERTICAL CENTER OF BOUYANCY, VCB in M 0.66 1.33 1.96 2.59
15 LCF About Sta 5 (midship) 2.55 1.43 0.13 -1.10
16 WATER-PLANE AREA, AWP in sq. M 93.00 177.80 245.59 288.78

Page | 40
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 6

BONJEAN
CURVES OFFSET
AND PLAN

Page | 41
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 6:BONJEAN OFFSETS

PARTICULARS:
VALUE
LBP 31 Meters
BREADTH 11 Meters
DEPTH 5 Meters
DRAFT 4 Meters
WATERLINE SPACING 0.5 Meter
STATION SPACING 3.1 Meters
DIVISOR 180

STA WL 1 WL 2 WL 3 WL 4

FP
0.000 0.000 0.000 0.000
0.5
0.000 0.070 1.998 6.359
1
0.000 1.643 6.029 12.129
1.5
0.308 3.880 10.000 17.282
2
1.350 6.531 13.912 22.236
3
2.918 10.545 19.729 29.494
4
3.986 12.748 22.870 33.384
5
4.446 13.582 23.943 34.675
6
2.981 11.780 22.041 32.655
7
0.000 4.160 13.833 24.222
8
0.000 0.000 5.960 15.900
8.5
0.000 0.000 2.202 11.715
9
0.000 0.000 0.735 8.988
9.5
0.000 0.000 0.000 5.970
AP
0.000 0.000 0.000 1.409

DIVISOR = /15

Page | 42
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 7

STABILITY

Page | 43
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 7: STABILITY

• VERTICAL CENTER OF BUOYANCY (VCB)

Reference: Elements of Ship Design by R. Munro-Smith, Chapter 5, P. 64

FORMULA 1:
VCB = d x (0.9 - (0.36 x Cm))
where: d - draft, 4m
= 4 x (0.9 - (0.36 x 0.79)) Cm - 0.79

VCB = 1.8468 m

FORMULA 2:
VCB = d x (0.9 - 0.36 x Cm - 0.1 x Cb)
where: d - draft, 4m
= 4 x (0.9 - 0.36 x 0.79 - 0.1 x 0.49) Cm - 0.79
Cb - 0.49
VCB = 1.9938 m

FORMULA 3:
VCB = d x (0.78 - 0.285 x Cm / Cw)
where: d - draft, 4m
= 4 x (0.78 - 0.285 x 0.79/0.85) Cm - 0.79
Cw - 0.85
VCB = 1.545 m

FORMULA 4:
VCB = 0.52 x d

= 0.52 x 4 where: d - draft, 4m

VCB = 2.08 m

FORMULA 5:
VCB = 0.535 x d

= 0.535 x 4 where: d - draft, 4m

VCB = 2.14 m

VCB AVERAGE
VCB AVE. = 1.847 + 1.994 + 1.545 + 2.08 + 2.14
5

VCB AVE. = 1.921 m

Page | 44
 ASIAN INSTITUTE OF MARITIME STUDIES

• VERTICAL CENTER OF GRAVITY (VCG)

Reference: Elements of Ship Design by R. Munro-Smith, Chapter 5, P. 64

FORMULA 1:
VCG = 0.01D x ((46.6 + 0.135 x 0.81 - Cb) x (L/D)2)
where: D - depth, 5m
2
= 0.01(5) x ((46.6+0.135x0.81-0.49)x(31/5) ) Cb - 0.49
L - LBP, 31 m
= 0.01(5) x (46.6 + 0.135 x 0.32 x 38.44 )

VCG = 2.41 m

FORMULA 2:
VCG = 0.75 x D

= 0.75 x 5 where: D - depth, 5m

VCG = 3.75 m

VCG AVERAGE
VCG AVE. = 2.42 + 3.75
2

VCG AVE. = 3.085 m

• TRASNVERSE METACENTER (BMT)

Reference: Elements of Ship Design by R. Munro-Smith, Chapter 5, P. 64

FORMULA :
BMT= k x B2
h x Cb where: B - breadth, 11m
h - draft, 4 m
0.061 x 112 Cb - 0.49
=
4 x 0.49 k - constant, 0.061

BMT= 3.77 m

Page | 45
 ASIAN INSTITUTE OF MARITIME STUDIES

• LONGITUDINAL METACENTER FROM CENTER OF BUOYANCY (BML)

Reference: Theoretical Naval Architecture by Attwood & pangelly, P. 156

FORMULA 1:
2 2
3 x Cwl x LBP
BML =
40 x d x Cb
where: LBP - 31m
2 2
3 x 0.85 x 31 d - draft, 4 m
=
40 x 4 x 0.49 Cb - 0.49
Cwl - 0.85
BML = 26.57 m

FORMULA 2:
BML = 1.25 x LBP

1.25 x 31 where: LBP - 31m

BML = 38.75 m

BML AVERAGE
BML AVE. = 26.57 + 38.75
2

BML AVE. = 32.66 m

• HEIGHT OF METACENTER ABOVE KEEL (KMT)

Reference: Elements of Ship Design by R. Munro-Smith, Chapter 5, P. 63

FORMULA :
Cw
KB= H
Cwl + Cb
where: h - draft, 4 m
0.85 Cb - 0.49
= 4
0.85 + 0.49 Cwl - 0.85

KB = 2.595 m

KMT = KB + BMT

= 2.54 + 3.77 where: BMT - 3.72

KMT = 6.365 m

Page | 46
 ASIAN INSTITUTE OF MARITIME STUDIES

• LONGITUDINAL METACENTRIC HEIGHT ABOVE KEEL (KML)

Reference: Theoretical Naval Architecture by Attwood & pangelly, P. 156

FORMULA :
KML = VCB + BML
where: BML- 26.57 m
= 1.921 + 26.57 VCB - 1.921 m

KML = 28.491 m

• TRANSVERSE METACENTER HEIGHT (GMT)

Reference: Theoretical Naval Architecture by Attwood & pangelly

FORMULA :
BG = KG - KB
where: KG = VCG = 3.085 m
= 3.085 - 2.595 KB - 2.595 m

BG = 0.49 m

GMT = BMT - BG

= 3.77 - 0.49 where: BMT - 3.77m

GMT = 3.28 m

• TRANSVERSE MOMENT OF INERTIA

Reference: Ship Design and Performance for Masters and Mates, P. 48

FORMULA :
IT = BMT x Vol. of Displacement
where: BMT - 3.72m
3
= 3.72 x 668.90 Vol. of Displ. - 668.9 m

IT = 2488.308 m4

• LONGITUDINAL MOMENT OF INERTIA

Reference: Ship Design and Performance for Masters and Mates, P. 48

FORMULA :
IT = BML x Vol. of Displacement
where: BML - 32.66 m
= 32.66 x 668.90 Vol. of Displ. - 668.9 m 3

IT = 21.846.274 m4

• ROLLING PERIOD (s)

Reference: Elements of Ship Design

0.44 x B
T=
√GM where: GM - 3.28 m
B - breadth, 11 m
0.44 x 11
=
√3.28

= 2.67 x2

T= 5.34 s

Page | 47
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 8

SCANTLING
COMPUTATION

Page | 48
 ASIAN INSTITUTE OF MARITIME STUDIES

INTRODUCTION TO SCANTLING

The Midship section. The first thing needed for one to have an idea of the various

members that will compose the ship’s frame and hull the design that will compose the ship

frame and the hull is the design of amidship section. This is reference for it will determine

the frame spacing of the members.

The Classification process consists of a) the development of Rules, Guides,

standards and other criteria for the design and construction of marine vessels and

structures, for material, equipment and machinery, b) the review of design and survey

during and after construction to verify compliance with such Rules, Guides, standards or

other criteria and c) the assignment and registration of class when such compliance has

MidshipsSectionA drawing of the cross section of a ship halfway between theintersection

s of its stem and stern with the design waterline.

This is reference for it will determine the frame spacing of your members, the

scantling height, the unsupported span and others.

The most important duty of the ships structure design is to supply a strong enough

structure against the internal and external loads. It may be considered as the material

which provides the strength and stiffeners to withstand all of the loads which the ship may

reasonably be expected to experience. The Hull girder is the structure which resist

longitudinal bending, consisting basically of the shell plating, decks inner bottom,

longitudinal bulkheads and girders. The hull girder must withstand to both static and

dynamic storm sea conditions, as well as during launching and dry docking

Page | 49
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 8 : SCANTLING COMPUTATION

PARTICULARS:
VALUE
L.B.P. 31 METERS
BREADTH MOULDED 11 METERS
DEPTH MOULDED 5 METERS
DRAFT 4 METERS

FRAME SPACING
• FRAME SPACING (Chapter E, Section 7.01, page 85)
The standard spacing of frames is to be calculated in accordance with following formula
(whichever is lesser):
S = 720 (L / 100)1/4 mm

1/4 mm
= 720 (31 / 100) where: L - LBP, 31 m

S = 537.25, adopt to lowest frame spacing , 508 mm or 0.508 m

PLATINGS
• BOTTOM SHELL PLATING (Chapter E, 3.01 - (c), page 55)
In a ship transverse bottom framing, the thickness t of bottom shell plating within 0.4 L
amidship is not to be less than:

where: S - frame spacing - 508 mm

t = 7.839 mm, adopt to 8 mm

• KEEL PLATE (Chapter E, Section 3.01 - (a), page 54)

The width b of the keel plate is not to be less than obtained from the following formula:
The thickness t of the keel plate is not to be less than:
b = 900 + 3.5L mm t = 0.1 L + 5 mm

= 900 + 3.5 (31) = 0.1 (31) + 5 where: L = LBP, 31 m

b = 1008.5 mm t = 8.1, adopt to 9.525 mm

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

Page | 50
 ASIAN INSTITUTE OF MARITIME STUDIES

PLATINGS
• SIDE SHELL PLATING ( Chapter E, 3.02 - (b), No. 2, page 56)
Where the side shell is framed transversely, the thickness t of the side shell plating
within 0.4 L amidhips is not to be less than the greates of the folowwing values:

where: S - frame spacing - 508 mm

t = 7.44 mm, adopt to 8 mm

• SHEER STRAKE( Chapter E, 3.02 - (d), page 57)

The width b of sheerstrake is not to be less than that obtain from the following formula:
b = 870 + 4.5L mm
where: L - Length of vessel - 31 m
= 870 + 4.5 (31)
note: thickness of sheer strake is the same as
b = 1009.5 mm the thickness of side shell plating

• DECK PLATING (Chapter E, 4.02 - No. 4, page 62)

The thickness t of strength deck plating amidship outside the line openings is, in
additional to the compliance of the above requirments of section modulus, not to be less
than that obtrained from the following formula:
t = 0.05 L + 5, mm

= 0.05 (31) + 5 where: L - Length of vessel - 31 m

t = 6.55 mm

Chapter L, the thickness of strength deck plating is to satify the relevant requirements of
Section 1: Section 4, Chapter E, but the minimum thickness is to be increased by 1mm
Tugs
above the required by 4.02 of Chapter E. (page 253)

t = 7.55 mm, adopt to 8 mm

• STRINGER PLATE (Chapter E, 4.03, page 62)

The width b of stringer plate is not to be less than that obtain from the following formula:
b = 6.8 L + 500 mm
where: L - Length of vessel - 31 m
= 6.8 (31) + 500
note: thickness of stringer plate is the same as
b = 710.8 mm the thickness of deck plating

Reference: PRSRules
Reference: PRS Rulesforfor
thethe Contsruction
Contsruction andand Classification
Classification of Steel
of Steel VesselVessel

Page | 51
 ASIAN INSTITUTE OF MARITIME STUDIES

TRANSVERSE FRAMINGS
• SIDE STRINGER Chapter G, Section 7.05, page 200)
The section modulus W of side stringers is not to be less than that obtained from the
following formula:
W = 13b (h + 1.2) l2

2
W = 13(b) x ( h + 1.2) x l where: b - half breadth, B/2, 5.5 m
h - vertical distance measured from
= 13(5.5) x ( 1.524 + 1.2) x 22 the stringer deck at side, 1.524m
l - span of frame, 2 m
3
W = 779.064 cm

• LONGITUDINAL STRENGTH (WEB FRAME) (Chapter E, 7.03, page 88)

Web frames are to be fitted in the engine room, and are to be space not more than 5 or
not less than 2 frames apart. The section modulus W of web frames is not to be less than
obtained from the following fromula:

W = 0.2*n*C*W
where: n - 2 to 5 frames apart, 2 frames apart
W - sectional area of main frame
= 0.2*2*7.07*79.96 20 8.4
79.96 C
200 4.4
W = 226.127 cm 3 C = 7.0676
C - obtained through interpolation

• CENTER KEELSON (Chapter E, 5.01, page 67)

The depth of the center keelson is to be the same as that of floors, and the web thickness
t and the sectional area A of the face plate of the center are not to be less than

2
t = 0.06 * L + 6.2 mm A = 0.5 L + 2 cm

= 0.06 * 31 + 6.2 = 0.5*31 + 2 cm2 where: L - Length of vessel - 31 m

2
t = 8.06 mm, adopt to 9.525 mm A = 17.5 cm

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

Page | 52
 ASIAN INSTITUTE OF MARITIME STUDIES

TRANSVERSE FRAMINGS
• SIDE KEELSON (Chapter E, 5.04, page 70)
The depth of side keelson is to be the same as that of floors, and the web thickness t and the
sectional area A of the face plate of side keelsons are not to be less than the following values:

2
t = 0.05 * L + 5 mm A = 0.2 L + 4 cm

= 0.05 * 31 + 5 = 0.2*31 + 4 cm2 where: L - Length of vessel - 31 m

t = 6.55 mm A = 10.2 cm 2

• FLOORS (Chapter E, 5.07, page 71)

For ships having a transveresly framed single bottom, floors are to be fitted at every frame and
are to have a section modulus W, web thickness t and depth h not less than:

• W = 4.1 sdB2 + 340 cm3

= 4.1(245.872) + 340

W = 1348.08 cm3
where: s - frame spacing, 0.508 m
• h = kB mm
d - draft, 4m
= 51*11

h = 561 mm B - breadth, 11 m
*adopt to 930 mm adjustment from
the frame computation
2
• t = 0.01*h + 3, mm s*d*B = 245.872

= 0.01*561 + 3, mm k = obtained through interpolation

10 50
t = 8.61 mm 11 k
*adopt to 8 mm adjustment from 16 56
the bottom plating
k = 51
2 2
• A = 0.05 s*d*B + 8, cm

= 0.05*245.872 + 8, cm2 u

A = 20.29 cm 2

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel
Reference: PRS Rules for the Contsruction and Classification of Steel Vessel
Page | 53
 ASIAN INSTITUTE OF MARITIME STUDIES

TRANSVERSE FRAMINGS
• TRANSVERSE FRAMING (ORDINARY BOTTOM) (Chapter E, 6.17, page 77)
The thickness t of plate floors is not to be less than that obtained from the following formula:

t = 0.03 L + 5 s + 2.6 mm where: L - Length of ship in m, 31 m

S - frame spacing in m, 0.508 m
= 0.03(31) + 5(0.508) + 2.6

t =6.07, adopt to 6.350 mm

The section modulus of bottom ordinary is not to be less than obtained from the following
formula:

2 3
W = 5.5s*h*l cm
where: s - spacing of stiffeners, in m (1.5)
2
= 5.5 x (1.5) x (5.05) x (0.93) h - tank top to deck + height
of air pipe, 5.05 m
3
W = 36.03 cm l - height of floors, 0.930 m

• WATER HEAD (Chapter E, 8.01, page 90)

The calculated water head h of decks is to be determined in accordance with the following
requirements:
A. the calculated water head of the weather strength deck is not to be less than that
obtained from the following formula:
h = 0.0072*L + (d/D) - 0.21, m where: L - Length of vessel - 31 m
when L>140 m, it is to be taken as 140 m

= 0.0072*140 + (4/5) - 0.21

d/D s - the ratio of draft to the
h = 1.598 m calculated molded depth

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

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 ASIAN INSTITUTE OF MARITIME STUDIES

TRANSVERSE FRAMINGS
• DECK BEAMS (Chapter E, 8.02, page 91)
The section modulus W of deck beams for each deck in multi-deck ship is not to be less
than that obtained from the following formula:

W = C*s*h*l2 cm3 where: s - beam spacing, 6ft or 1.83m

h - water head in m
2
= 6.67*1.83*1.598*2.75 l - span of beam, (B/2)/2 = 2.75 m
C - coefficients, 6.67
3
W =147.51 cm
• DECK GIRDERS (Chapter E, 8.07, page 94)
The section modulus W of deck girders is not to be less than that obtained from the
following formula:

W = C*b*h*l2 cm3 where: C - coefficients, 6.67

h - water head in m
2 l - span of girder, 2.44 m
= 6.6*5.5*1.598*2.44
b - mean width of deck
W = 345.35 cm 3 supported by the girder, B/2 = 5.5 m

• DECK TRANSVERSE (Chapter E, 8.21, page 102)

The section modulus W of strength deck or tween deck transverse is not to be less than
that obtained from the following formula:

2 3
W = 7*S*h*l cm where: S - spacing of transverse in m, .508 m
h - water head in m
2 l - span of deck transverse, 1.375 m
= 7*0.508*1.598*1.83

W = 131.11 cm 3

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

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 ASIAN INSTITUTE OF MARITIME STUDIES

WATERTIGHT BULKHEAD
• PLANE BULKHEAD PLATING (Chapter E, 11.09, page 118)
The thickness t of the plating of plane watertight bulkheads is not to be less than that
obtained from the following formula:

.3 mm and is not to be less than 5.5 mm

where: s - spacing of stiffeners, in m
beam, (B/2)/2 = 2.75 m .3 h - vertical distance in m, from
lower edge of the plate in a strake to
t = 5.38 mm, adopt to 5.5 mm bulkhead deck on the center line

• PLANE BULKHEAD STIFFENERS (Chapter E, 11.09, page 118)

The section modulus W of vertical stiffeners of bulkheads is not to be less than that obtained
from the following:

W = C*s*h*l2 cm3 where: s - spacing of stiffener, in m (0.508)

h - vertical distance in m, 2 m
= 3.3*0.508*2*22 l - span of stiffeners, in m, 2 m
C - coefficients to be taken as 3.3
3
W =13.41 cm

*multiply the * -
computed W to 3
W = 16.76 cm
125%

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

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 ASIAN INSTITUTE OF MARITIME STUDIES

LONGITUDINAL FRAMINGS
• DECK LONGITUDINAL (Chapter E, Section 8.17, page 100)
Where the deck is frame longitudinally, the section modulus of deck longitudinal is to be
determined as follows:

W = C*s*h*l2 cm3 where: s - spacing of longitudinals, in m (0.508)

h - water head in m, 1.598 m
2 l - span of longitudinals in m, 2 m
= 16.802*0.508*1.598*2
C - coefficient, 16.802
3
W = 54.56 cm

• BOTTOM LONGITUDINAL (Chapter E, Section 6.33, page 81)

The section modulus W of bottom longitudinal is not to be less than that obtained from
the following formula:

W = 11.5 C*s*d*l2 cm3 where: s - spacing of longitudinals, in m (0.508)

d - molded draft in m, 4 m
2 l - span of longitudinals in m, 1.83 m
= 11.5(1) * 0.508 * 4 * 1.83
C - coefficient, 1 (no intermediate
3
W = 78.26 cm vertical strut)

Reference: PRS Rules for the Contsruction and Classification of Steel Vessel

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 ASIAN INSTITUTE OF MARITIME STUDIES

length (plate)
50.8

thickness
(plate)
0.8

H y=
9 2.716
thickness
(AB)
0.8

7.5
w
DECK LONGITUDINAL

SCANTLING/ SIZE
A dg Adg Adg2 Inertia
MEMBER t l
Deck Plating 0.8 50.8 40.640 0.4 16.256 6.502
Angle Bar 0.8 9 x 7.5 12.64 7.084 89.542 634.314 99.4
2
Total Area: 53.280 Total Adg: 105.798 Total Adg 740.216

New dg Adg / Area 1.986 REQUIRED:

New A(dg) Area x New dg

2
210.082 54.56

New Icg Total Adg 2 -New Adg 2 530.134

NEED SM VALUE:
Top "c" total height - New dg 7.814
Required*.3+Required
New SM New Icg / Top "c" 67.842
70.928
Percentage New SM - Req. / Req. 0.243

24%

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 ASIAN INSTITUTE OF MARITIME STUDIES

w
7.5

thickness
(AB)
0.8
H
y= 12.5
4.136

0.8
thickness
(plate)

50.8
length (plate)

BOTTOM LONGITUDINAL

SCANTLING/ SIZE
A dg Adg Adg2 Inertia
MEMBER t l
Deck Plating 0.8 50.8 40.640 0.400 16.256 6.502
Angel Bar 0.8 12.5 X 7.5 15.49 9.164 141.950 1300.833 247.3
Total Area: 56.130 Total Adg: 158.206 Total Adg 2 1554.635

New dg Adg / Area 2.819 REQUIRED:

2
New A(dg) Area x New dg 445.916 78.26

New Icg Total Adg 2 -New Adg 2 1108.720

NEED SM VALUE:
Top "c" total height - New dg 10.481
Required*.3+Required
New SM New Icg / Top "c" 105.779
101.738
Percentage New SM - Req. / Req. 0.352

35%

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 ASIAN INSTITUTE OF MARITIME STUDIES

w
7.5

thickness
(AB)
0.6
H
y= 10
4.036

0.8
thickness
(plate)

50.8
length (plate)

ORDINARY BOTTOM (TRANSVERSE)

SCANTLING/ SIZE
A dg Adg Adg2 Inertia
MEMBER t l
Deck Plating 0.8 50.8 40.640 0.400 16.256 6.502
Angel Bar 0.6 10x7.5 10.25 6.764 69.331 468.955 102.4
2
Total Area: 50.890 Total Adg: 85.587 Total Adg 577.857

New dg Adg / Area 1.682 REQUIRED:

2
New A(dg) Area x New dg 143.941 36.03

New Icg Total Adg 2 -New Adg 2 433.917

NEED SM VALUE:
Top "c" total height - New dg 9.118
Required*.3+Required
New SM New Icg / Top "c" 47.588
46.839
Percentage New SM - Req. / Req. 0.321

32%

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 ASIAN INSTITUTE OF MARITIME STUDIES

length (flange) length (web) thickness (plate)

11 22 0.8

thickness (web)
0.8

length (plate)
50.8

0.8
thickness (flange)

WEB FRAME/ TRANSVERSE FRAME

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.400 16.256 6.502 0
Web 0.8 22 17.600 11.800 207.680 2450.624 709.87
Flange 0.8 11 8.8 23.200 204.160 4736.51 0
Total A= 67.040 Total Adg= 428.096 Total Adg2= 7903.51

New dg Adg / Area 6.386 REQUIRED:

New A(dg) Area (new dg)^2 2733.684 226.127

New Icg Sum Adg2-New Adg2 5169.821

NEED SM VALUE:
Top "c" total height - New dg 17.214
Required*.3+Required
New SM New Icg / Top "c" 300.321
293.9651
PercentageNew SM - Req. / Req. 0.328

33%

note: all units used in frames are in centimeters

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 ASIAN INSTITUTE OF MARITIME STUDIES

length (plate) thickness (plate)

50.8 0.8

length
(web)
40

0.8
thickness
length (web)
(flange) .
22

0.8
thickness (flange)

SIDE STRINGER

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.4 16.256 6.502 0
Web 0.8 40 32.000 20.8 665.600 13844.48 4266.667
Flange 0.8 22 17.6 41.2 725.120 29874.9 0
Total A= 90.240 Total Adg= 1406.976 Total Adg2= 47992.59

New dg Adg / Area 15.591 REQUIRED:

New A(dg) Area (new dg)^2 21936.851 779.064

New Icg Sum Adg2-New Adg2 26055.742

NEED SM VALUE:
Top "c" total height - New dg 26.009
Required*.3+Required
New SM New Icg / Top "c" 1001.816
1012.7832
Percentage New SM - Req. / Req. 0.286

29%

note: all units used in frames are in centimeters

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 ASIAN INSTITUTE OF MARITIME STUDIES

length (plate)
50.8

thickness (plate)
0.8
thickness
(flange)
length (web) 0.6
27

0.6 17 `
thickness(web) length (flange)

DECK GIRDER

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.400 16.256 6.502 0
Web 0.6 27 16.200 14.300 231.660 3312.74 984.150
Flange 0.6 17 10.2 28.100 286.620 8054.02 0
Total A= 67.040 Total Adg= 534.536 Total Adg2= 12357.41

New dg Adg / Area 7.973 REQUIRED:

New A(dg) Area (new dg)^2 4262.063 345.35

New Icg Sum Adg2-New Adg2 8095.349

NEED SM VALUE:
Top "c" total height - New dg 20.427
Required*.3+Required
New SM New Icg / Top "c" 396.314
448.955
Percentage New SM - Req. / Req. 0.148

15%

note: all units used in frames are in centimeters

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 ASIAN INSTITUTE OF MARITIME STUDIES

thickness (web)
0.8
thickness (plate)
0.8

thickness (flange) 50.8

0.8 length
(plate)

16
length
(web)

10
length (flange)

DECK BEAM

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.400 16.256 6.502 0
Web 0.8 16 12.800 8.800 112.640 991.23 273.067
Flange 0.8 10 8 17.200 137.600 2366.72 0
Total A= 61.440 Total Adg= 266.496 Total Adg2= 3637.52

New dg Adg / Area 4.338 REQUIRED:

New A(dg) Area (new dg)^2 1155.926 147.51

New Icg Sum Adg2-New Adg2 2481.595

NEED SM VALUE:
Top "c" total height - New dg 13.263
Required*.3+Required
New SM New Icg / Top "c" 187.114
191.763
Percentage New SM - Req. / Req. 0.268

27%

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 ASIAN INSTITUTE OF MARITIME STUDIES

thickness (web)
0.8
thickness (plate)
0.8

thickness (flange) 50.8

0.8 length
(plate)

14
length
(web)

10
length (flange)

DECK TRANSVERSE

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.400 16.256 6.502 0
Web 0.8 14 11.200 7.800 87.360 681.41 182.933
Flange 0.8 10 8 15.200 121.600 1848.32 0
Total A= 59.840 Total Adg= 225.216 Total Adg2= 2719.16

New dg Adg / Area 3.764 REQUIRED:

New A(dg) Area (new dg)^2 847.631 131.11

New Icg Sum Adg2-New Adg2 1871.533

NEED SM VALUE:
Top "c" total height - New dg 11.836
Required*.3+Required
New SM New Icg / Top "c" 158.117
170.443
Percentage New SM - Req. / Req. 0.206

21%

Page | 65
 ASIAN INSTITUTE OF MARITIME STUDIES

length
(flange)
0.8

thickness 0.8
(web) thickness
0.8 (flange)
93
length
(web) thickness
(plate)
0.8
50.8
length
(plate)

FLOORS

MEMBERS/ SCANTLING SIZE (t x l) Area dg Adg Adg^2 Inertia

Plate 0.8 50.8 40.640 0.4 16.256 6.502 0
Web 0.8 93 74.400 47.3 3519.12 166454.4 53623.80
Flange 0.8 0.8 0.64 94.2 60.288 5679.13 0
Total A= 115.680 Total Adg= 3595.66 Total Adg2= 225763.81

New dg Adg / Area 31.083 REQUIRED:

New A(dg) Area (new dg)^2 111763.482 1348.08

New Icg Sum Adg2-New Adg2 114000.326

NEED SM VALUE:
Top "c" total height - New dg 63.517
Required*.3+Required
New SM New Icg / Top "c" 1794.796
1752.504
PercentageNew SM - Req. / Req. 0.331

33%

Page | 66
 ASIAN INSTITUTE OF MARITIME STUDIES

ABS RULES FOR BUILDING AND CLASSING

STEEL VESSELS UNDER 90 IN LENGTH
Part 3: Chapter 2: Hull Structure and Arrangements, Section 1 Longitudinal Strength
3 Longitudinal Hull Girder Strength

SM = C1xC2xL2xB(Cb + 0.7) m-cm2

where: C1 - 15.20-0.22L 24<or=L<35m

C2 - 0.01
L - LBP
B - Breadt h
Cb - 0.49 but is not t o be t aken as
less t han 0.60

2
SM = ( 15.20 - 0.22( 31 ) ) x 0.01 ( 31 ) x 11 ( 0.60 + 0.7 )

SM = 1151.60 m-cm2

DIMENSION 2
a*dg a*dg
2
Qty a (cm ) dg (M) 2 h (M) io
L T (cm -M) (cm -M2) 2

ABOVE A.N.A.
PLATING:
Deck Plating 2 479.3 0.8 766.88 2.154 1651.860 3558.11 0
Stringer Plate 2 71.08 0.8 113.728 1.987 225.978 449.02 0
Sheer Strake 2 100.95 0.8 161.52 1.462 236.142 345.24 0
Side Shell Plating 2 96.64 0.8 154.624 0.483 74.683 36.07 5
GIRDER:
Deck Girder
b. Flange 1 17 0.6 10.2 1.895 19.329 36.628 0 0
c. W eb 1 27 0.6 16.2 2.055 33.291 68.413 0.27 984.15
Deck Side Girder
b. Flange 2 17 0.6 20.4 1.895 38.658 73.3 0 0
c. W eb 2 27 0.6 32.4 2.033 65.869 133.9 0.54 984.15
Deck Side Girder
b. Flange 2 17 0.6 20.4 1.895 38.658 73.3 0 0
c. W eb 2 27 0.6 32.4 1.977 64.055 126.6 0.54 984.15
Deck Side Girder
b. Flange 2 17 0.6 20.4 1.895 38.658 73.3 0 0
c. W eb 2 27 0.6 32.4 1.892 61.301 116.0 0.54 984.15
LONGITUDINALS:
Deck Longitudinals 14 9 x 7.5 0.8 176.96 2.135 377.810 806.6 0 99.4

Page | 67
 ASIAN INSTITUTE OF MARITIME STUDIES

BELOW A.N.A.
PLATING:
Side Shell Plating 2 58.55 0.8 93.68 0.293 27.448 8.04 0 0
Chine 2 139.93 0.8 223.888 1.24 277.621 344.25 0 0
Bottom Shell Plating 2 405.02 0.8 648.032 2.932 1900.030 5570.89 0 0
Keel Plating 2 50.4 0.9525 96.012 2.991 287.172 858.93 0 0
STRINGER:
Side Stringer
b. Flange 2 22 0.8 35.2 0.140 4.928 0.7 0.44 709.867
c. W eb 2 40 0.8 64 0.140 8.960 1.3 0 0
LONGITUDINALS:
Bottom Longitudinals 2 12.5 x 7.5 0.8 30.98 2.42 74.972 181.4 0 247.3
Bottom Longitudinals 2 12.5 x 7.5 0.8 30.98 2.56 79.309 203.0 0 247.3
Bottom Longitudinals 2 12.5 x 7.5 0.8 30.98 2.787 86.341 240.6 0 247.3
Bottom Longitudinals 2 12.5 x 7.5 0.8 30.98 2.884 89.346 257.7 0 247.3
TOTAL
TOTAL AREA: 2843.24 TOTAL ADG 5753.46 2 19297.04
ADG

New dg Adg / Area 2.024

REQUIRED:
New A(dg) Area x (New dg) 2 11642.434
1151.6
New Icg Sum Adg 2 -New Adg 2 7654.603

Top "c" total height - New dg 5.306 NEED SM VALUE:

New SM New Icg / Top "c" 1442.510 Required*.3+Required

Percentage New SM - Req. / Req. 0.253 1497.08

25%

Page | 68
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 9

BOLLARD PULL
COMPUTATION

Page | 69
 ASIAN INSTITUTE OF MARITIME STUDIES

WHAT IS BOLLARD PULL?

Bollard pull is a conventional measure of the pulling (or towing) power of a vessel.

It is defined as the force (tons or kilonewtons (kN)) exerted by a vessel under full power,

on a shore-mounted bollard through a tow-line, commonly measured in a practical test (but

sometimes simulated) under test conditions that include calm water, no tide, level trim, and

sufficient depth and side clearance for a free propeller stream.

BOLLARD PULL CALCULATION

Since the bollard pull is given in owner's requirements. To calculate the
displacement of the tow, I will use the bollard pull formula to get the data I need. The

2/3 3
D xV
BP = (
120 x 60
+ Cmw x B x D1 )xK
Where: BP - Bollard Pull (tons, 70 tons)
D - Displacement of the tow (tons)
B - width of the tow (m, 31 m)
D1 - Height of the wind facing above water level
including deck cargo, freeboard + deck house

• 2 situations (for k, v, and Cmw)

Ordinary towing condition (BFT. 4)

V - 6 knots (I will use 7 knots as my ordinary towing
condition, equivalent to my service speed)
Cmw - 0.0025
K=>3

Keep on station during heavy weather (BFT 10 - 11)

V - 3 knots
Cmw - 0.015
K=8

Page | 70
 ASIAN INSTITUTE OF MARITIME STUDIES

• To get the Displacement of the barge, we are going to use the existing barge particulars to
determine the displacement.

Particulars: LOA 91.5 m d 5.5 m

B 24.4 m deck house 3.66 m
D 8m

2/3 3
D xV
BP = ( 120 x 60
+ Cmw x B x D1 )xK

D2/3 x V3
BP = ( 7200
+ Cmw x B x D1 )xK

BP x 7200 = D2/3 x V3 x K + Cmw x B x D1 x K x 7200

( BP x 7200 ) - ( Cmw x B x D1 x K x 7200 ) = D2/3 x V3 x K

2/3 3
( BP x 7200 ) - ( Cmw x B x D1 x K x 7200 ) =D xV xK
3 3
V xK V xK

(BP x 7200) - (Cmw x B x D1 x K x 7200)

(
3/2
3
V xK ) = ( D2/3 ) 3/2

(70 x 7200) - (0.0025 x 24.4 x 6.16 x 4 x 7200) =D

(
3/2
3
7 x4
)

504, 000 - 10 821.888

(
3/2
1372
) =D

6815.136 tonnes = D

Page | 71
 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 10

POWERING AND
PROPULSION

Page | 72
 ASIAN INSTITUTE OF MARITIME STUDIES

INTRODUCTION TO POWERING

One of the most important considerations for a naval architect is the powering

requirement for a ship. Once the hull form has been decided upon, it is necessary to

determine the amount of engine power that will enable the ship to meet its operational

requirements. Knowing the power required to propel a ship enables the naval architect to

select a propulsion plant, determine the amount of fuel storage required, and refine the

ship’s center of gravity estimate.

A moving ship experience resisting force from the water and air which must

overcome by a thrust supplied by some thrust-producing mechanism

One of the most important considerations for a naval architect is the powering requirement

for a ship. Once the hull form has been decided upon, it is necessary to determine the

amount of engine power that will enable the ship to meet its operational requirements.

Knowing the power required to propel a ship enables the naval architect to select a

propulsion plant, determine the amount of fuel storage required, and refine the ship’s

center of gravity estimate.

Testing of full-scale ships and models determined that the power required to propel

a ship through the water was directly related to the amount of resistance a hull experiences

when moving through the water.

Ship resistance is defined as the force required towing the ship in calm water at a constant

velocity.

Page | 73
 ASIAN INSTITUTE OF MARITIME STUDIES

POWERING

Length Between Perpendicular 31 M 101.68 ft

Breadth 11 M 36.08 ft
Depth 5 M 16.4 ft
Draft 4 M 13.12 ft
Block Coefficient (Cb) 0.49
Midship Coefficient (Cm) 0.79
Prismatic Coefficient (Cp) 0.62
Displacement 685.069 MT 673.85 LT
Trial Speed (Free running speed) 12 Knots 20.28 ft/sec
Bollard Pull 70
No of screw 2

In powering of tugboats, I'll be using the powering made by Capt. P. Zahalka, Association of
Hanseatic Marine Underwriters to determine the BHP I'm going to use to power my vessel

Recommended Initial Powering and Propeller selection procedure for towing

The requirement for this particular case is that it should have a Bollard Pull of about.
BHP
Fixed Pitch Propeller: (free wheeling) (BHP x 1.00/100) 7000
Fixed Pitch Propeller and Kort Nozzle (BHP x 1.08/100) 6481
Controllable Pitch Propeller: (free wheeling) (BHP x 1.125/100) 6222
Controllable Pitch Propeller and Kort Nozzle (BHP x 1.126/100) 6217

For this particular case we will use a Controllable Pitch Propeller and Kort Nozzle and please
note further that the limited aperture of the hull dictates that it should use 2 propellers. The
estimated BHP is calculated with reference to its bollard pull and on this condition the propeller
is design. The free running speed is also calculated as shown hereunder.

No. of Delivered
BHP EHP
Propeller HP
6217 3419.18
2
3108.35 1709.59 2412.08

To check the BHP and EHP recommened, I'll be using another way to determine the power of the
vessel to be designed by using the Speed and Power of Ships by D.W. Taylor tabular form

Page | 74
 ASIAN INSTITUTE OF MARITIME STUDIES

POWERING CALCULATION FROM D.W. TAYLOR

• WETTED SURFACE COEFFICIENT (CWS)

The wetted surface coefficient can be obtain from the graph in figure 20 - Contour of Wetted
Surface Coefficient

CWS = 15.45

• WETTED SURFACE

WS = CWS √Δ L

= 15.45 √(698.7)(101.68)

WS = 4118.05 ft2

• EFFECTIVE HORSEPOWER FACTOR

(a) = 0.00307 x Δ x √ L

= 0.00307 x (698.7) x √101.68

= 0.00307 x 698.7 x 10.08

(a) = 21.62

• WETTED SURFACE CORRECTION FACTOR

Ws = Cws / 15.4

15.45 / 15.4

Ws = 1.003

• LENGTH CORRECTION FACTOR (L)

0.085
f(design) x 150
λ= 0.085
L(design) x f150

to get the f, I need to interpolate the value of it from the Table V. Tideman's frictional constant
of ships in salt water

Length of ship (feet) f

100 0.0097
101.68 fx
150 0.00957

101.68 - 100
fX = 0.0097 + ( 150 - 100
)(0.009570 - 0.00970)

fX = 0.0097

0.085
f(design) x 150
λ= 0.085
L(design) x f150

0.009695 x 1500.085
=
(101.68)0.085 x 0.00957

λ= 1.047

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 ASIAN INSTITUTE OF MARITIME STUDIES

• BREADTH-DRAFT RATIO

B/d = 36.08 / 13.12

B/d = 2.75

• BREADTH-DRAFT CORRECTION FACTOR

= (B/d - 2.25) / 1.5

= 2.75 - 2.25 / 1.5

= 0.333

• FINAL Rf / Δ CORRECTION FACTOR (b)

( Cws )
b= xλ
15.4

15.45
b= xλ
15.4

b= 1.0503

• WEATHER AND APPENDAGE ALLOWANCE

Wa = 15%
Aa= 5%

Total = 20%

• HULL EFFICIENCY

(1 - t )
EH =
(1 - w)

where:
Wake Fraction:

(w) = -0.05 + 0.5Cb

= -0.05 + 0.5(0.49)

(w) = 0.195

(t) = thrust deduction factor

= 0.3Cb

= 0.3(0.49)

(t) = 0.147

(1 - t )
EH =
(1 - w)

(1 - .147 )
=
(1 - .195)

EH = 1.059

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 ASIAN INSTITUTE OF MARITIME STUDIES

•TRANSMISSION EFFICIENCY

ET = Loses between delivered power (at tailshaft) and that provided by engine)

ET = 0.98 for engine(s) abaft according to Ship Resistance and Propulsion, p. 10

•RELATIVE ROTATIVE EFFICIENCY

ER = range from 1.0 to 1.10 to all types of ship according to Baxter, Naval
Architecture, p. 212

ER = 1.05

•PROPELLER EFFICIENCY

EP = 60% to 75% according to Ship Design and Performance for Master

and Mates, p. 69
assume EP = 70%

•MECHANICAL EFFICIENCY

EM = 95% to 100%

EM = 98%

•AIR FOIL EFFICIENCY

EA = 96% to 98 %

EA = 97%

•PROPULSIVE COEFFICIENT

PC = EH x ET x ER x EP x EM x EA

= 1.059 x 0.98 x 1.05 x 0.7 x 0.98 x 0.97

PC = 0.725

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 ASIAN INSTITUTE OF MARITIME STUDIES

SUMMARY OF THE RESULTS:

Length L (ft) = 101.680 √L = 10.080
Breadth B (ft) = 36.080 ∆/(L/100)3 = 641.000
Draft d (ft) = 13.120 CP = 0.62
∆ tons = 673.850 B/H = 2.75
CM = 0.790 V/√L = 1.2
2
AM ft = 374.190
Wetted surface coefficient, cws = 15.45
WS correction factor = 1.003
Breadth-draft correction factor = 0.333
Length correction factor, α = 1.05
Final Rf/∆ correction factor, b = 1.050
EHP correction factor, a = 21.620
Propulsive Coefficient = 0.725

HORSEPOWER TABLE
1 2 3 4 5 6 7
Rr/∆ Rf/∆ from
Rr/Δ from contours
correction contours for
Difference Rf/∆
v/√L for B/H
(col.2-col.3)
150' ship
(col.6 * b)
B/H = 3.75 B/H = 2.25 (col.5x B-d and cws
corr.factor) 15.45
1.15 21.50 16.75 1.582 4.750 32.525 34.161
1.20 30.75 27.50 1.082 3.250 39.555 41.545
1.25 39.85 31.65 2.731 8.200 48.675 51.123

8 9 10 11 12 13 14

Rr/∆ Rt/∆ EHP EHP Total HP BHP

Vs
(col.3 + (col.7 + FACTOR (col.9 * (col.11 * (col.13 /
(col.1 * √L)
col.4) col.8) (col.1 * a) col.10) 1.25) PC)

18.332 52.493 24.863 1305.127 11.592 1631.409 2250.220

28.582 70.127 25.944 1819.371 12.096 2274.214 3136.847
34.381 85.504 27.025 2310.744 12.600 2888.430 3984.042
Reference: Speed and Power by D.W. Taylor
From this table, The Effective horse power (EHP) and The Break Horsepower (BHP) can be
obtained from the horsepower table, with the value of v/√Δ = 1.20, the EHP and BHP can be
determined

EHP from the table BHP from the table

1819.371 3136.847

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 ASIAN INSTITUTE OF MARITIME STUDIES

In conclusion, I'll be using the Powering Calculation from D.W. Taylor for it gives a specific
way to determine the required EHP and BHP of the vessel to be designed. From this, I'll be
using the BHP to check the Mechanical effenciency loss and to get the range of my required
main engine BHP requirements

Mechanical Efficiency 3136.847 3136.847

Loss (5%) = 100% - 5%
= 0.95
3301.944 hp 2462.26 kW

Mechanical Efficiency 3136.847 3136.847

Loss (10%) = 100% - 10%
= 0.90
3485.385 hp 2599.05 kW

Therefore, the designated engine BHP range is from 3301.944 (2462.26 kW) hp to
3485.385hp (2599.05kW)
ENGINE SELECTED:
MAN L27/38
BHP = 3426.311 hp RPM = 800

• SHAFT HORSEPOWER

SHP= BHP(engine selected) x 97%

3426.311 x 0.97

SHP= 3324 hp

• SHAFT HORSEPOWER

DHP = SHP x 98%

= 3323.52 x 0.98

DHP = 3257 hp

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ASIAN INSTITUTE OF MARITIME STUDIES

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 ASIAN INSTITUTE OF MARITIME STUDIES

PROPULSION
The basic idea behind an azimuth thruster is that the propeller can rotate 360 degrees round
a vertical axis providing omni-directional controlled thrust. This means superior
maneuverability for vessels equipped with azimuth thrusters. It also eliminates the need for a
rudder and a reverse gear.

The system consists of several different devices: azimuth thrusters, steering and control unit
levers and shaft lines. As a whole, they might well be more accurately referred to as
“propulsion and steering system”.

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 11

CAPACITY PLAN
COMPUTATION

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 ASIAN INSTITUTE OF MARITIME STUDIES

WATER BALLAST (P/S) WATER BALLAST (P)

FRAME NO. -2 - 0 FRAME NO. 50 - 56
ρ= 1.025 tons/m
3
ρ= 1.025 tons/m
3

S.M Area F(A) S.M Area F(A)

1 13.04 13.04 1 0.37 0.37
4 11.88 47.52 4 3.01 12.04
1 8.57 8.57 1 4.95 4.95
∑F(A) 69.13 ∑F(A) 17.36
Spacing (m) 1.31 0.66 Spacing (m) 3.05 1.53
3 3
Total Volume = 30.19 m Total Volume = 8.82 m
Capacity = 30.94 tons Capacity = 9.05 tons

WATER BALLAST (S) WATER BALLAST (P/S)

FRAME NO. 50 - 56 FRAME NO. 56 - 61
ρ= 1.025 tons/m
3
ρ= 1.025 tons/m
3

S.M Area F(A) S.M Area F(A)

1 0.37 0.37 1 3.38 3.38
4 3.01 12.04 4 4.57 18.28
1 4.95 4.95 1 9.81 9.81
∑F(A) 17.36 ∑F(A) 31.47
Spacing (m) 3.05 1.53 Spacing (m) 2.89 1.45
Total Volume = 8.82 m3 Total Volume = 30.32 m3
Capacity = 9.05 tons Capacity = 31.07 tons

FRESH WATER TANK (P/S) F.O. T. No. 1 (P)

FRAME NO. 11 - 22 FRAME NO. 14 - 20
ρ= 1 tons/m 3 ρ= 0.86 tons/m 3
S.M Area F(A) S.M Area F(A)
1 1 1.00 1 1.16 1.16
4 3.58 14.32 4 0.69 2.76
1 6.79 6.79 1 0.36 0.36
∑F(A) 22.11 ∑F(A) 4.28
Spacing (m) 5.59 2.80 Spacing (m) 3.05 1.53
3 3
Total Volume = 41.20 m Total Volume = 2.18 m
Capacity = 41.20 tons Capacity = 1.87 tons

F. O. T. No. 2 (S) F. O. T. No. 3 (P)

FRAME NO. 14 - 20 FRAME NO. 20 - 29
ρ= 0.86 tons/m
3
ρ= 0.86 tons/m
3

S.M Area F(A) S.M Area F(A)

1 1.16 1.16 1 0.88 0.88
4 0.69 2.76 4 1.63 6.52
1 0.36 0.36 1 2.77 2.77
∑F(A) 4.28 ∑F(A) 10.17
Spacing (m) 3.05 1.53 Spacing (m) 4.57 2.29
3
Total Volume = 2.18 m Total Volume = 7.75 m3
Capacity = 1.87 tons Capacity = 6.66 tons

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 ASIAN INSTITUTE OF MARITIME STUDIES

F. O. T. No. 4 (S) F. O. T. No. 5 (P/S)

FRAME NO. 20 - 29 FRAME NO. 23 - 29
ρ= 0.86 tons/m 3 ρ= 0.86 tons/m 3
S.M Area F(A) S.M Area F(A)
1 0.88 0.88 1 3.33 3.33
4 1.63 6.52 4 3.93 15.72
1 2.77 2.77 1 4.39 4.39
∑F(A) 10.17 ∑F(A) 23.44
Spacing (m) 4.57 2.29 Spacing (m) 3.05 1.53
Total Volume = 7.75 m3 Total Volume = 23.83 m3
Capacity = 6.66 tons Capacity = 20.49 tons

F. O. T. No. 6 (P/S) F. O. T. No. 7 (P/S)

FRAME NO. 45 - 50 FRAME NO. 50 - 56
ρ= 0.86 tons/m 3 ρ= 0.86 tons/m 3
S.M Area F(A) S.M Area F(A)
1 5.52 5.52 1 9.18 9.18
4 4.43 17.72 4 6.55 26.20
1 3.5 3.50 1 3.82 3.82
∑F(A) 26.74 ∑F(A) 39.20
Spacing (m) 2.54 1.27 Spacing (m) 3.05 1.53
Total Volume = 22.64 m3 Total Volume = 39.85 m3
Capacity = 19.47 tons Capacity = 34.27 tons

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 ASIAN INSTITUTE OF MARITIME STUDIES

SUMMARY

FUEL OIL TANK

NAME LOCATION LCG CU. M TONS
F. O. T. No. 1 FRAME 14 - 20 -7.37 2.18 1.87
F. O. T. No. 2 FRAME 14 - 20 -7.37 2.18 1.87
F. O. T. No. 3 FRAME 20 - 29 -2.29 7.75 6.66
F. O. T. No. 4 FRAME 20 - 29 -2.29 7.75 6.66
F. O. T. No. 5 FRAME 23 - 29 -3.04 23.83 20.49
F. O. T. No. 6 FRAME 45 - 50 8.25 22.64 19.47
F. O. T. No. 7 FRAME 50 - 56 11.11 39.85 34.27
Total : 91.30 tons

WATER BALLAST TANK

NAME LOCATION LCG CU. M TONS
Water Ballast Tank FRAME -2 - 0 -16.25 30.19 30.94
Water Ballast Tank FRAME 50 - 56 11.11 8.82 9.05
Water Ballast Tank FRAME 50 - 56 11.11 8.82 9.05
Water Ballast Tank FRAME 56 - 61 13.97 30.32 31.07
Total : 80.11 tons

FRESH WATER TANK

NAME LOCATION LCG CU. M TONS
Fresh Water Tank FRAME 11 - 22 -7.63 41.20 41.20
Total : 41.20 tons

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 12

MINIMUM SAFE
MANNING

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 ASIAN INSTITUTE OF MARITIME STUDIES

MANNING REQUIREMENTS

•GROSS TONNAGE (GT)

GT = (CGT x L x B x D x Cb ) / 2.83 where: L - Length
B - Breadth
(1.10 x 31 x 11 x 5 x 0.49) / 2.83 D - Depth
Cb - Block Coefficient
GT = 324.733 T C GT - 0.85 - 1.10
(for tug boat)

•NET TONNAGE (GT)

NT = CNT x GT
where: C NT - 0.5 - 0.75
0.75 x 324.733 T (for tug boat)

NT = 243.55 T

SHIPS ENGAGED IN HARBOR, BAY, LAKE AND RIVER VOYAGE

COMPLEMENTS
PMMRR 1997, Appendix A, 4.4 Tugs and Dredgers

4.4.1 DECK DEPARTMENT

TONNAGE NO. POSITION LICENSE/QUALIFICATION

1 Master 3rd Mate/MAP MIP
Over 250 1 Deck Officer
2 Deck Ratings

4.4.2 ENGINE DEPARTMENT

TONNAGE NO. POSITION LICENSE/QUALIFICATION

1 Chief Engr. Officer 4th Marine Engr.
Over 400
2 Engine Ratings

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ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 13

WEIGHT
ESTIMATE

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 ASIAN INSTITUTE OF MARITIME STUDIES

LIGHTSHIP WEIGHT
• STEEL HULL

SHULL = LBP x B x D x cB x 0.112

31m x 11m x 5m x 0.49 x 0.112

SHULL = 93.5704 T

• EQUIPMENT, WOOD AND OUTFIT

Reference: Naval Architecture as Art and Science by Liljegren, page 47

E.W.O. = C x (Eq. No.) 2/3 where:

C = 0.90
0.90 x 12.7875 2/3 Eq. No. = 0.75xLxBxD / 100
12.7875
E.W.O. = 4.923 T

• ALLOWANCE WEIGHT FOR SUPERSTRUCTURE AND DECKHOUSE FITTINGS

A weight = 20 % of E.W.O.

0.20 x 4.923 MT

A weight = 0.98 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

NON-PAYING

• FUEL OIL CONSUMPTION

A. Full Output 2 x 3108.5 BHP @ 800 rpm

2 x 2318 kW @ 800 rpm

B. Fuel Oil Consumption

1. Main Engine (32.5 tons dry weight x 2)

FOCME = Main Engine (100% MCR) x Fuel Output/ ρ fuel oil

1000

where: Main Engine 188 g /

(100% MCR ) = kW hr
Full Output = 2318 kW
ρ Fuel oil = 0.86 kg/L

= 188 g/kW hr x 2318 kW / 0.86 kg/L

1000

= 374.77 x 2 (twin screw)

FOCME = 749.54 L/hr

2. Auxiliaries

FOCAUX = 10 % of main engine consumption

0.10 x 749.54 L/hr

FOC AUX = 74.954 L/hr

TOTALFOC = FOCAUX + FOCME

749.54 L/hr + 74.954 L/hr

TOTALFOC = 824.494 L/hr

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 ASIAN INSTITUTE OF MARITIME STUDIES

3. Round Trip
No. of Hours = D (6080 ft / 1 NM)
S (6080 ft / 1 NM - hr)

where: D - Distance (from Zamboanga to Davao)

320 Nautical Miles x 2 (round trip)
640 Nautical Miles
S - Service Speed
7 Knots

No. of Hours = 6080 ft/ 640 Nautical Miles

6080 ft / 7 NM - hr

No. of Hours = 91.43 hrs or 3.81 days or 4 days

C. Required total Fuel Oil Consumption per Round Trip

FOCT = TOTALFOC x No. of Hours

= 824.494 L/hr x 91.43 hrs

= 75, 383.49 L

(convert to m 3 ) '= 75, 383.49 L x 1 m3 / 1000 L

= 75.38 m3 + 1.25% bad weather allowance

= 94.23 m3 x ρ fuel density (0.86 Kg/L = 860 kg/m3 = 0.86 tonnes / m3)

FOCT = 81.04 T

• LUBE OIL CONSUMPTION

5% of Fuel Oil Consumption

LOCT = 81.04 T x 0.05

LOCT = 4.052 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

• FRESH WATER CONSUMPTION

A. Drinking and Ordinary Use

1. Number of officers and crews - 8 men

2. Water consumption per peson per day - 45 lbs

3. Number of days per trip - 4 days

F.W.C. = No. of Person x Water Consumption x No. of days

= 8 men x 45 lbs/person/day x 4 days

= 1440 lbs

convert to kg = 1440 lbs x 1 kg / 2.205 lbs

= 653.06 kg

convert to tons = 653.306 kg x 1 ton / 1000 kg

F.W.C. = 0.65 T

B. Washing and Sanitary Purpose

Reference: Principles of Naval Architecture Vol. I, p. 66

Same as drinkining and ordinary use 0.65 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

• PROVISIONS
Reference: Principles of Naval Architecture Vol. I, table 4, p. 96

1. Number of officers and crews - 8 men

2. Provisions per Person per day - 10 lbs

3. Number of days per trip - 4 days

Required Provisions = No. of person x Provision x No. of days

= 8 men x 10 lbs/person/day x 4 days

= 320 lbs

convert to kg = 320 lbs x 1 kg / 2.205 lbs

= 145.12 kg

convert to tons = 145.12 kg x 1 ton / 1000 kg

Required Provisions = 0.15 T

• STORES

1. Number of officers and crews - 8 men

2. Stores per Person per day - 11 lbs

3. Number of days per trip - 4 days

Required Stores = No. of person x Stores x No. of days

= 8 men x 11 lbs/person/day x 4 days

= 352 lbs

convert to kg = 352 lbs x 1 kg / 2.205 lbs

= 159.64 kg

convert to tons = 159.64 kg x 1 ton / 1000 kg

Required Stores = 0.16 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

• CREW WEIGHT
Reference: Principles of Naval Architecture Vol. I, p. 96

1. Number of officers and crews - 8 men

2. Average weight per person - 160 lbs

Crew Weight = No. of person x Ave. Weight per person

= 8 men x 160 lbs / person

= 1280 lbs

convert to kg = 1280 lbs x 1 kg / 2.205 lbs

= 580.50 kg

convert to tons = 580.50 kg x 1 ton / 1000 kg

Crew Weight 0.58 T

• CREW EFFECT

1. Number of officers and crews - 8 men

2. Average weight of baggage per person - 1 / 12 of a ton

Crew Effect = No. of person x Ave. Weight of baggage per person

= 8 men x 1 / 12 of a ton / person

Crew Effect = 0.667 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

SUMMARY
• LIGHTSHIP WEIGHT

1. Steel hull 93.5704 T

2. E.W.O. (Equipment, Wood and Outfittings) 4.923 T

3. Allowance Weight for Superstructure and Deckhouse 0.98 T

4. Main Engine Weight 65 T

Total = 164.473 T

• NON-PAYING

1. Fuel Oil (Total fuel oil consumption per Round Trip) 81.04 T

2. Lube Oil 4.052 T

3. Drinking and Ordinary Use 0.65 T

4. Washing and Sanitary Purpose 0.65 T

5. Provisions 0.15 T

6. Stores 0.16 T

7. Crew 0.58 T

8. Crew Effect 0.667 T

Total = 87.949 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

• Deadweight

Lightship Displacement = Lightship weight + Non-paying

= 164.473 T + 87.949 T

Lightship Displacement = 252.422 T

Deadweight = Loaded Δ - Lightship Δ

685 T - 252.422 T

Deadweight = 432.578 T

• Paying Deadweight

DWT = Deadweight - Non-Paying

432.578 T - 87.949 T

DWT = 344.629 T

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 14

FIREFIGHTING
SYSTEM

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 ASIAN INSTITUTE OF MARITIME STUDIES

Fire Fighting System

29.1 General
Fire extinguishing system and fire protection equipment is to be provided in
accordance with the applicable requirements of the "Rules for Building and Classing Steel
Vessels" except where vessels are below 1,000 gross tons. The following alternative
requirements are applicable.

29.3 Fire Pumps

29.3.1 Number of Pumps
Two power driven fire pumps are to be installed one of which may be attached to
the propulsion unit. Where vessels are less than 20 m (65 ft) in length one power driven
pump which may be an attached and one hand operated fire pumps are to be provided.
Sanitary bilge and general service pumps may be accepted as fire pumps.

29.3.2 Capacity
Fire pump capacity is to be in accordance with the following:

Vessel's length Minimum Capacity

3
Below 20 m (65ft) 5.5 m / hr (25 gpm)

20 m (65 ft) or greater but

3
below 30.5 m (100 ft) 11.0 m / hr (50 gpm)

30.5 m (100 ft) or greater

3
but below 1, 000 gross tons 14.3 m / hr (66.6 gpm)

Power driven fire pumps are to have sufficient pressure to supply the effective
3
stream required. Hand-operated fire pumps are to have a minimum capacity of 1.1 m / hr
(5 gpm)

29.5 Hoses, Nozzles and Hydrants

Hoses are not to have a diameter greater than 38 mm(1.5 in. ). Hoses for vessels
under 20 m (65 ft) in length may be garden type of good commercial grade having a
diameter of not less than 16 mm (0.63 in. ). Nozzles size are to be in accordance with the
"Rules fir Building and Classing Steel Vessels". Fire hydrants are to be of sufficient
number and so located that anu part of the vessel may be reached with an effective
stream of water from a single length of hose not exceeding 15 m ( 50 ft ). All hoses
attached to hydrants serving machinery spaced of vessels over 20 m. (65 ft) are in
addition to be fitted wuth nozzles suitable for spraying water on oil or alternatively, dual
purpose nozzles.

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 ASIAN INSTITUTE OF MARITIME STUDIES

29.7 Fixed Systems

A fixed fire-estinguishing system is to be provided for the machinery space of
vessels over 300 gross tons and 1,000 horsepower. Fixed system on pleasure yachts and
supply vessels will be specially considered. A fixed fire extnguishing system is to be
provided for the cargo spcaes and pump room of tankers. The cargo space system is to
be of the gas or foam type.

29.9 Fireman's Outfits

Fireman's outfits are not required, however, one fire axe is to be provided.

29.9 Portable Extinguishers

Portable extinguishers are to be provided in the quantities and locations indicated:

Table 29.1
Classification of Portable and Semi-portable Extinguishers

Soda-acid and Foam Carbon Dry

Classification
water liters liters dioxide Chemical
Type Size (U.S. Gal.) (U.S. Gal.) (U.S. Gal.) (U.S. Gal.)
A II 9 (2.5) 9 (2.5) - -
B II - 9 (2.5) 6.8(15) 4.5(10)
C II - - 6.8(15) 4.5(10)

Table 29.2
Portable and Semi-portable Extinguishers

Space Classification Quantity and Location

•Safety Areas
1 in each main corridors not more
Communicating
A - II than 46 m (150 ft) apart. May be
corridors lcoated in stairways

Radio room C - II 1 in vicinity of exit

•Accomodations
1 in each sleeping accommodation
Sleeping
A - II space (where occupied by more than 4
Accommodations persons)

•Service Spaces
B - II or 1 for each 230 m2 (2,500 ft2) or
Galleys
C - II fraction therof for hazards involve

1 for each 230 m2 (2,500 ft2) or fraction

Storerooms A - II therof located in vicinity of exits, either
inside or outside of spaces

•Machinery Spaces
Internal combustion or
gas turbine engines B - II 1 for each engine

Electric motor or
generators of open C - II 1 for each motors or generators
type

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 15

GENERAL
ARRANGEMENT
PLAN

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 ASIAN INSTITUTE OF MARITIME STUDIES

CHAPTER 15

DRAWING PLAN

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