MARINE FUELS

 Residual oil: it is the heaviest fraction of the distillation of crude oil, with high viscosity (=> pre-heating

necessary => used only in large ships) and high concentration of pollutants (e.g. sulphur). Its combustion
produces a much darker smoke than other fuels and it needs specific temperature for storage and pumping. Due
to these drawbacks, it is also the cheapest liquid fuel on the market.
 IFO 180 (Intermediate Fuel Oil) : it is a mix of 98% of residual oil and 2% of distillate oil.

 IFO 380 (Intermediate Fuel Oil) : it is a mix of 88% of residual oil and 12% of distillate oil. Due to the higher

content in distillate oil, IFO 380 is more expensive than IFO 180.
 MDO (Marine Diesel Oil) : it mainly consists of distillate oil and has a lower sulphur content than the three fuels

described above.
 MGO (Marine Gas Oil) : it is pure distillate oil and has the lowest sulphur content.

(ICCT, Air Pollution and GHG Emissions from Ocean-going Ships: Impacts, Mitigation Options and Opportunities for Managing Growth, March 2007)  

************************************************************************************

Heavy Fuel Oil (HFO)

The generic term heavy fuel oil (HFO) describes fuels used to generate motion and/or fuels to generate heat that
have a particularly high viscosity and density. In the MARPOL Marine Convention of 1973, heavy fuel oil is defined
either by a density of greater than 900 kg/m³ at 15°C or a kinematic viscosity of more than 180 mm²/s at 50°C.
Heavy fuel oils have large percentages of heavy molecules such as long-chain hydrocarbons and aromatics with
long-branched side chains. They are black in color.

Heavy fuel oils are mainly used as marine fuel, and HFO is the most widely used marine fuel at this time; virtually
all medium and low-speed marine diesel engines are designed for heavy fuel oil. But older steam locomotives and
oil-fired power plants also generate energy from heavy fuel oils.

Heavy fuel oil is a residual fuel incurred during the distillation of crude oil. The quality of the residual fuel depends
on the quality of the crude oil used in the refinery. To achieve various specifications and quality levels, these
residual fuels are blended with lighter fuels such as marine gasoil or marine diesel oil. The resulting blends are
also referred to as intermediate fuel oils (IFO) or marine diesel oil. They are classified and named according to
their viscosity. The most commonly used types are IFO 180 and IFO 380, with viscosities of 180 mm²/s and 380
mm²/s, respectively. If there is a predominance of heavy fuel oil in a blend, it is assigned to the heavy fuel oil
category. As these are blends of heavy fuel oil and lighter fuels, they can also be referred to as a heavy marine
diesel oil. Heavy fuel oil cannot generally be pumped at a temperature of 20°C, and must therefore be preheated
in the ship's tanks. To ensure the fuel is or remains pumpable, it must be heated to at least 40°C. At a
temperature of 15°C, IFO has a bitumen-like consistency.

The ISO 8217 international standard divides marine fuels into distillate fuels and residual fuels. The latter are
collectively called heavy fuel oils. An exception is the lowest viscous quality level, RMA 10, which is no longer
referred to as an HFO, as its proportion of heavy fuel oil is so small. ISO 8217 stipulates that residual fuels, and
therefore all heavy fuel oils, may not contain old oil or lubricating oils.

A key differentiator of heavy fuel oils is their sulfur content. According to ISO 8217, their maximum sulfur content
must not exceed 3.5%. The following main classes with regard to the sulfur content can be distinguished:

Marine fuel Max. sulfur content

High sulfur fuel oil (HSFO) 3.5%

Low sulfur fuel oil (LSFO) 1.0%

Ultra low sulfur fuel oil (ULSFO) 0.1%

Low sulfur fuel oil (LSFO)

Heavy fuel oils are referred to as low sulfur fuel oil (LSFO) if their sulfur content is below 1%. Usually these are
marine fuel types IFO 180 or IFO 380, which have been desulfurized. Until the end of 2014, ships could still travel
through Emission Control Areas (ECAs) with this type of marine fuel. 

Ultra-low sulfur fuel oil (ULSFO)

Since January 1, 2015, in accordance with Annex VI of the MARPOL Conventions, ship emissions must contain no
more than 0.1% sulfur in such protected areas (ECAs). Due to these tightened restrictions, LSFOs no longer play an
appreciable role in these areas and have been virtually replaced with the ultra-low sulfur fuel oil (ULSFO) marine
fuel, which complies with those limits. Theoretically, heavily desulfurized IFO fuels could also be used here, but in
practice the desulfurization of such heavy fuel oils is too expensive to make economic sense. For this reason,
today the term ultra-low sulfur fuel oil usually refers not to desulfurized heavy fuel oils, but to marine gasoil,
which is already low in sulfur. It is composed exclusively of distillates and has a sulfur content of under 0.1%. This
marine fuel is also known as ultra-low marine gasoil. ULSFO is used in medium- to high-speed diesel engines.
When converting from LSFO to ULSFO, it must be ensured that the engine technology is compatible with ULSFO.

High-sulfur fuel oil (HSFO)

The alternative to using marine fuels with such low sulfur content in ECAs is the use of scrubbers. This technology
involves injecting water into the exhaust stream to reduce sulfur and other emissions. However, refitting a ship
with this technology costs several million euros and means that the ship is docked for a period of time, which
leads to a loss in revenue and income for the shipowners. On the other hand, a scrubber allows higher-sulfur
marine fuels to be used. In this context, such heavy fuel oils are designated as high-sulfur fuel oils (HSFO), which
have a maximum sulfur content of 3.5% as permitted under ISO 8217.

More information about global maritime regulations and the setting of emission limits can be found in the article
on Marine Fuels (Bunker Fuels).
Viscosity of Bunker Oil - Marine Fuel Oil
Distillate Fuels, residual Fuels

What is Bunker Oil? - Description and Classification Overview

Bunker oil is generally any type of fuel oil used aboard ships. We can distinguish between two main types:
distillate fuels and residual fuels.

Marine fuels are classified using the “Bunker ABC”:

 Bunker A corresponds to the distillate fuel oil No. 2

 Bunker B is a No. 4 or No. 5 fuel oil
 Bunker C corresponds to the residual fuel oil No. 6

No. 6 is the most common oil, that's why "bunker fuel" is often used as a synonym for the No. 6 residual fuel oil
which requires heating before the oil can be pumped.

No. 5 fuel oil is also called “navy special”. No. 5 or No. 6 also furnace fuel oil (FFO).

In the maritime field another classification is used:

 MGO (Marine Gas Oil): a distillate fuel oil (No. 2, Bunker A)

 MDO (Marine Diesel Oil): a blend of MGO and HFO
 IFO (Intermediate Fuel Oil): a blend of MGO and HFO, with less gasoil than MDO
 MFO (Medium Fuel Oil): a blend of MGO and HFO, with less gasoil than IFO
 HFO (Heavy Fuel Oil): a residual fuel oil (No. 6, Bunker C)

Marine fuels are traditionally classified according to their kinematic viscosity. This is a valid criterion for oil
quality as long as the oil is produced by atmospheric distillation only. Today, almost all marine fuels are based on
fractions from more advanced refinery processes and the viscosity itself says little about the oil's quality as fuel.
Despite this, marine fuels are still quoted on the international bunker markets with their maximum viscosity set
by ISO 8217 as marine engines are designed to use different viscosities of fuel.

The density is also an important parameter for fuel oils since marine fuels are purified before use to remove
water and dirt. Therefore, the oil must have a density which is sufficiently different from water.
Viscosity Tables – Measurement data

Distillate Bunker Oils (ISO 8217)

Distillate Fuel Kin. Viscosity [mm²/s] at 50°C Density [g/cm³] at 15°C

DMA 1.5 ... 6.0 < 0.890

DMB < 11 < 0.900
DMC < 14 < 0.920
DMX 1.4 ... 5.5 −

Residual Bunker Oils (ISO 8217)

Residual Fuel Kin. Viscosity [mm²/s] at 50°C

RMA 30 < 30
RMB 30 < 30
RMD 80 < 80
RME 180 < 180
RMF 180 < 180
RMG 380 < 380
RMH 380 < 380
RMH 700 < 700
RMK 380 < 380
RMK 700 < 700

Marine Diesel Oil (MDO) & Intermediate Fuel Oil (IFO)

 The term marine diesel oil (MDO) generally describes marine fuels that are composed of various blends of
distillates (also called marine gasoil) and heavy fuel oil. Unlike diesel fuels on land that are used for cars and
trucks, marine diesel oil is not a pure distillate. The different blending ratios of marine diesel oil can be controlled
directly by processes in the refinery or by blending ready-made marine fuels. Marine diesel is similar to diesel
fuel, but has a higher density. Unlike heavy fuel oil (HFO), marine diesel oil does not have to be heated during
storage.

Marine diesel oil is sometimes also used synonymously with the term “intermediate fuel oil” (IFO). In the strict
sense, the term marine diesel oil mainly refers to blends with a very small proportion of heavy fuel oil. This type
of marine diesel oil is therefore also classified as a distillate in some textbooks, which means it is also categorized
as a middle distillate. Intermediate fuel oils, on the other hand, have a higher proportion of heavy fuel oil.
Accordingly, IFO types with particularly high proportions of heavy fuel oil are sometimes classified as heavy fuel
oils in some textbooks, standards/norms and publications. This results in the following brief descriptions:

 Marine diesel oil in general: a blend of distillates and heavy fuel oil
 Marine diesel oil in a narrow sense: Blend of distillates and heavy fuel oil, but with very low heavy fuel oil
content 
 Intermediate fuel oil (IFO): Marine diesel with higher proportions of heavy fuel oil

According to the ISO 8217 "Petroleum Products – Fuel (class F)" international standard, marine diesel oil with a
lower proportion of heavy fuel oil include the DMB and RMA 10 fuels. The heavy fuel oil components in DMB
marine diesel oil – which is classified as a distillate according to ISO 8217 – come mainly from residues of heavy
fuel oil from tanks where DMB is stored. Due to this pollution by heavy fuel oil, its color changes can range from
light brown to black. As emission limits for Emission Control Areas (ECAs) become ever stricter, DMB with its
relatively high sulfur content of about 2% is being used much less frequently.

According to ISO 8217, marine diesel oil RMA 10 already counts as a residual fuel. It has a similarly low viscosity to
DMB, but a higher maximum permissible sulfur content of 3.5%, and also a higher proportion of heavy fuel oil.
Therefore, this type of fuel is also usually darker than DMB. Its color spectrum starts from dark brown and
likewise ends in black.

Intermediate fuel oils are black due to their higher proportion of heavy fuel oil. In ISO 8217, IFO fuels with RME,
RMG and RMK designations and viscosities of 180 mm²/s or 380 mm²/s count as residual fuels. These marine
diesel oils are already so viscous that they must be heated so that they can be pumped at all.

Marine diesel oil is sold with different sulfur content levels. For example, IFO 180 and IFO 380 can have a
maximum sulfur content of 3.5% according to ISO 8217. They are also sold in a low-sulfur variant, which has a
sulfur content of less than 1%. Ships could even enter an Emission Control Area (ECA) with the latter. However, if
ship-owners use an engine-fuel combination with a high sulfur content, the emission limit values can also be met
by using additional technology (filter systems, scrubbers).

Their different blending ratios make it possible to use marine diesel oil in many different engines. Lighter versions
like DMB and RMA 10 are used to power smaller medium- to high-speed marine engines and auxiliary power
units, as well as auxiliary engines on very large ships, while the viscous IFO 380 is mainly used in large aggregates.
Lightweight and low-sulfur marine diesel oil is sometimes burned in larger engines as well – whenever an area
with stricter emission limits is being crossed. Once outside the area, the ship will switch back to a marine fuel with
higher emissions.

More information about global maritime regulations and setting emission limit values can be found in the article
on Marine Fuels (Bunker Fuels).

Lighter marine gasoil (MGO) and marine diesel oil (MDO) fuels are significantly more expensive than heavy fuel oil
(HFO), so that commercial shipping still uses heavy fuel oil for the most part.
What is the difference between MDO and MGO ?
Difference between MDO and MGO

The term marine diesel oil (MDO) generally describes marine fuels that are composed of various blends of
distillates (also called marine gasoil) and heavy fuel oil. Unlike diesel fuels on land that are used for cars and
trucks, marine diesel oil is not a pure distillate. The different blending ratios of marine diesel oil can be controlled
directly by processes in the refinery or by blending ready-made marine fuels. Marine diesel is similar to diesel
fuel, but has a higher density. Unlike heavy fuel oil (HFO), marine diesel oil does not have to be heated during
storage.

Marine diesel oil is sometimes also used synonymously with the term “intermediate fuel oil” (IFO). In the strict
sense, the term marine diesel oil mainly refers to blends with a very small proportion of heavy fuel oil. This type
of marine diesel oil is therefore also classified as a distillate in some textbooks, which means it is also categorized
as a middle distillate. Intermediate fuel oils, on the other hand, have a higher proportion of heavy fuel oil.
Accordingly, IFO types with particularly high proportions of heavy fuel oil are sometimes classified as heavy fuel
oils in some textbooks, standards/norms and publications. This results in the following brief descriptions:

Marine diesel oil in general: a blend of distillates and heavy fuel oil
Marine diesel oil in a narrow sense: Blend of distillates and heavy fuel oil, but with very low heavy fuel oil content 
Intermediate fuel oil (IFO): Marine diesel with higher proportions of heavy fuel oil

According to the ISO 8217 "Petroleum Products – Fuel (class F)" international standard, marine diesel oil with a
lower proportion of heavy fuel oil include the DMB and RMA 10 fuels. The heavy fuel oil components in DMB
marine diesel oil – which is classified as a distillate according to ISO 8217 – come mainly from residues of heavy
fuel oil from tanks where DMB is stored. Due to this pollution by heavy fuel oil, its color changes can range from
light brown to black. As emission limits for Emission Control Areas (ECAs) become ever stricter, DMB with its
relatively high sulfur content of about 2% is being used much less frequently.

According to ISO 8217, marine diesel oil RMA 10 already counts as a residual fuel. It has a similarly low viscosity to
DMB, but a higher maximum permissible sulfur content of 3.5%, and also a higher proportion of heavy fuel oil.
Therefore, this type of fuel is also usually darker than DMB. Its color spectrum starts from dark brown and
likewise ends in black.

Intermediate fuel oils are black due to their higher proportion of heavy fuel oil. In ISO 8217, IFO fuels with RME,
RMG and RMK designations and viscosities of 180 mm²/s or 380 mm²/s count as residual fuels. These marine
diesel oils are already so viscous that they must be heated so that they can be pumped at all.

Marine diesel oil is sold with different sulfur content levels. For example, IFO 180 and IFO 380 can have a
maximum sulfur content of 3.5% according to ISO 8217. They are also sold in a low-sulfur variant, which has a
sulfur content of less than 1%. Ships could even enter an Emission Control Area (ECA) with the later. However, if
ship-owners use an engine-fuel combination with a high sulfur content, the emission limit values can also be met
by using additional technology (filter systems, scrubbers).

Their different blending ratios make it possible to use marine diesel oil in many different engines. Lighter versions
like DMB and RMA 10 are used to power smaller medium- to high-speed marine engines and auxiliary power
units, as well as auxiliary engines on very large ships, while the viscous IFO 380 is mainly used in large aggregates.
Lightweight and low-sulfur marine diesel oil is sometimes burned in larger engines as well – whenever an area
with stricter emission limits is being crossed. Once outside the area, the ship will switch back to a marine fuel with
higher emissions.

Marine gas oil (bunker fuel or bunker oil) is any type of diesel which is used in seagoing vessels. The term ‘bunker’
is used for a vessels fuel storage tank and a marina’s fuel storage tank which is where the name ‘bunker fuels’
comes from.

The Marine Gas Oil (MGO) can be used in four-stroke machines and generators. This fuel meets the ISO-F DMA
specifications and the sulphur limit required for all European ports.
MARPOL Annex VI "Regulations for the Prevention of Air Pollution from Ships" stipulate that Heavy Fuel Oil (HFO)
combustion is not permitted during port stay and in specific areas at sea. The switchover to lighter types like
Marine Diesel Oil (MDO) or Marine Gas Oil (MGO) requires monitoring and some modifications to the burner and
fuel systems.

 MDO & MGO - Fuel property comparision

If special fuel such as low-sulphur fuel oil is not available in a port, the obvious choice of fuel would be a good
quality Marine Diesel Oil (MDO) or Marine Gas Oil (MGO). These two fuels differ in their properties, however, and
should be handled differently as described in the following.

Heat value(calorific value)

The heat value of lighter fuel oils is typically a little higher than the heat value of HFO.The additional heat input to
the boiler is, however, considered to have an insignificant influence on the boiler itself. In some cases, it may
nevertheless be necessary to re-adjust the air/fuel ratio if the pre-set air amount is beyond the limit and grey
smoke is generated.

Viscosity

Lighter oils commonly have lower viscosity and need not be preheated. When operating on fuel oil types of low
viscosity, it must be ascertained that the fuel pumps are indeed able to operate with the low viscosity.

It should also be considered that the viscosity mentioned in the specification is indicated with
a reference temperature and that the actual operation temperature might be higher causing the viscosity to drop
further.

Heat tracing should be shut off as should oil pre-heaters that have not been bypassed.

Density

Typically the density of lighter fuels is lower than of HFO (and MDO), which may have the result that the amount
of (lighter) fuel to the burner will differ from the amount original pre-set and thus for instance cause ignition
problems or
increased smoke emission.

This can happen because most marine installations have the oil amount pre-adjusted based on a calculation of the
main fuel, and on a manual volume calculation/ adjustment that takes its density into account.

Flash point

The flash point for some lighter fuels is occasionally lower than the requirements from the classification societies,
which should be considered when storing in the traditional fuel tanks onboard.

Lubricating properties

Lighter fuel oils traditionally also have lower lubricating properties. The hydrodynamic lubrication can, by using
the well-known Sommerfeld number, be described as a function of the viscosity, So = f (v) x k, for a certain pump.
This means that when the viscosity is reduced, the lubricating properties are reduced, which is an important
aspect to consider too, with relation to fuel pumps

Fuel system

Most of the components in the fuel system will not be affected by operation on a lighter fuel oil, but some
considerations have to be made.

Fuel pumps
It must be ascertained that the fuel pump can actually operate with the new fuel under the given operating
conditions. As most fuel pumps are either screw pumps or gear pumps, it is important to check if the pumps are
able to operate with the lower viscosity of the new fuel, as there is a risk of increased wear and tear as well as
breakdown if the pump is unsuited for the viscosity.
Fuel pumps running continuously during periods when the boiler/ burner is in standby position may heat up,
causing the temperature of the fuel to increase and thereby the viscosity to decrease. In this case, the control of
the pumps should be considered, too. In case the pump control system is not preset to do it already, it may be
preferable to adjust the control system in such a way that the pumps are always shut off when not required.

Fuel preheaters

Light fuels rarely need to be preheated, and if heating is unnecessary, the fuel pre-heaters should be bypassed
during operation on light fuel to avoid the risk of the oil being overheated.

Fuel pipe tracing

If the fuel does not need preheating, the fuel pipes do not need to be heated, and consequently the tracing of the
fuel pipes should be shut off. If preheating is necessary, check if the tracing is sufficient. Be careful that the tracing
does not heat the fuel more than necessary.

Change-over between fuels

When changing over/switching between fuels, make sure that fuel in the return/recirculation pipes is returned to
the correct fuel tank. Make sure that the new fuel is not preheated in an unintended way.

Burners

The fuel change-over affects the three common burner types normally supplied for marine boiler installations in
various ways. It is recommended a post-purge of the furnace whenever MGO has been used.

It should be observed that the lower viscosity for fuel pumps in systems supplied by most manufacturers is
normally 4.5 cSt. This means that if a fuel with a lower viscosity is used, the fuel pumps must be changed or
modified.

Pressure jet burner

Pressure jet burners are typically used on smaller boiler types and run on MDO, MGO and HFO. Installations
delivered by most manufacturers will typically be able to operate on both MGO/ MDO and HFO.

A lower viscosity may also cause an increase in the fuel input through the nozzle, and the risk of increasing smoke
emission arises.

Rotary cup burner

Rotary burners are used on all boiler types and run on MDO, MGO and HFO. Installations delivered by most
manufacturers will typically be able to operate on both MGO/MGO and HFO.

For smaller burners there should be no problem with operation on a lighter fuel; however, the fuel amount
(pressure) should be checked/adjusted in order to obtain a reasonably smoke-free combustion.

For larger burners, there is a risk of coke deposit creation in the burner cup, if the installation is not fitted with a
suitable heat shield. This happens because the heat radiation into the rotary cup generates a too high
temperature of the fuel in the rotary cup causing the fuel to start coking. It is therefore recommended having the
rotary cup installation checked and if necessary modified.

Steam atomizing burner

Steam atomizing burners are typically used on medium and larger boiler types and run on MDO, MGO and HFO.
As the viscosity of the fuel burned in the steam atomizing burner is commonly in the range 15–30 cSt, the lower
viscosity of a lighter fuel may cause over-firing if the pressure alone controls the oil amount to the burner.

For continuous operation with lighter fuels, it is recommended to use, either compressed air as the atomizing
medium, or changing the lance to a type that does not heat the fuel in the same way as the traditional lance.

Due to easier evaporation of lighter fuels, it is recommended to  adjust the control system so that the main
burner does not accidentally ignite in case of a missing ignition flame/ source, just as unnecessarily vaporized fuel
should be avoided.

Modifications to the existing boiler/burner system

When having to operate a boiler/burner system on a lighter fuel than originally intended for the plant, the
complete boiler/burner installation should be examined by authorized personnel, as this is not just a matter of
complying with legislation but equally so a serious safety matter.

Steam atomized burner lance

There are two options for the atomization (compressed air and steam) and burner lance design, and it is
recommended to change  the existing lance to a modified type where internal volume has been reduced to an
absolute minimum and specially designed to operate with MDO/MGO and with steam as atomizing medium. The
lance is constructed so the steam piping is insulated from the fuel piping in the burner lance thus avoiding
preheating.

Flame supervision

On burner plants, usually only one flame scanner is installed (main flame supervision) from the outset. It is
recommended to have two flame scanners for the main flame supervision and in addition one separate flame
scanner to detect the operation of the ignition burner.

Effects on Main engine fuel oil system

The lowest viscosity suitable for two-stroke diesel engines is 2 cSt at engine inlet. However, this viscosity limit
cannot necessarily be used as a fuel specification for purchasing the fuel, as the viscosity in a purchase
specification is tied to a reference temperature.  This is due to the fact that the external fuel systems have an
individual effect on the heating of the fuel and, thereby, the viscosity of the fuel when it reaches the engine inlet.

The external fuel oil systems on board today have been designed to keep a high temperature for HFO operation.
This can make it difficult to keep the fuel system temperature as low as possible, and thereby as high a viscosity as
possible, when changing to DO and GO operation.
Many other factors influence viscosity and its influence on the engine, such as engine condition and maintenance,
fuel pump wear, engine adjustment, actual fuel temperature in the fuel system, human factors, etc. Although
achievable, it is difficult to optimise all of these factors at the same time. This complicates operation on viscosities
in the lowest end of the viscosity range.
To build in some margin for safe and reliable operation, engine manufacturers recommends operators to test the
engine’s and external systems’ sensitivity to low viscosity. Furthermore, the necessity for installation of a cooler
or cooler & chiller should be evaluated before purchasing fuels with the minimum level of viscosity necessary.

In principle, fuels according to the specified grades DMX/ DMA can be purchased, if the engine and external
system are designed to keep a minimum viscosity of 2 cSt at engine inlet. If 3 cSt can be obtained, this is preferred
to ensure a higher safety margin.
HFO
HFO, also known as “residual fuel oil”, is based on the high viscosity, tar-like mass, which remains after the
distillation and subsequent cracking of crude oil in order to produce lighter hydrocarbon products, such as petrol ,
distillate diesel fuels and heating oil or feedstocks for lubricants.
The main components are alkanes,  cycloalkanes and different carbon hydrides. The boiling range is between
300°C and ~700°C.
Due to its semi-fluid consistence, HFO has to be preheated to make it combustible in engines.
RMA, RMB, RMD, RME, RMG or RMK are the international trade names. Cheap, but challenging
As a residual product, HFO is a relatively inexpensive fuel – it typically costs 30% less than distillate fuels
(MDO/MGO) (Verlinkung). It thus became the standard fuel for large marine diesel engines during the oil crisis in
the 1970s and 1980s, and it required extensive adaptation of the injection system and other components of low
and medium speed engines – which are still the only reciprocating engines capable of running on HFO.
 Most of our MAN medium speed liquid fuel engines  can burn heavy fuel oil (HFO). Of course, our medium speed
dual  fuel engines are capable of burning HFO in liquid fuel mode as well.
Fuel oil specification
Heavy fuel oil

 ISO 8217, ISO-F-RM K700

Fuel-system related characteristics values

Viscosity (at 50 °C) mm /s (cSt)

2
max. 700

Viscosity (at 100 °C) mm /s (cSt)

2
max. 55

Density (at 15 °C) kg/m 3

max. 1,010

Flash point °C min. 60

Pour point °C max. 30

Hydrogen sulfide mg/kg max. 2

Acid number mg KOH/g max. 2.5

Total sediment aged mass % max. 0.10

Engine-related characteristic values

Carbon residues (Conradson) m% max. 20

Sulphur m% max. 5

Ash m% max. 0.15

Vanadium mg/kg (=ppm) max. 450

Water Vol.% max. 0.5

Additional parameters

Aluminium and silicon mg/kg max. 60

Asphalts m% max. 2/3 of carbon residues (Conradson)

Sodium mg/kg Sodium < 1/3 vanadium, sodium < 100

Used lubricating oil (ULO) mg/kg Ca >30 and Zn >15 or CA >30 and P >15
All data provided on this site is for information purposes only, explicitly non-binding and subject to changes without further notice.
Diesel
Marine Diesel Oil is a blend of different middle distillates derived from the crude oil refining process. It is usually
composed of light and heavy gas oil, light and heavy cycle oil, as well as vacuum gas oil. The chemical components
are alkenes, cyclo alkanes and different carbon hydrides. The boiling range is between 200°C and ~500°C.
The international trading names are DMA (Marine Gas Oil/MGO) and DMB (Marine Diesel Oil/MDO). The main
differences between these fuels are their viscosities, densities, as well as their sulphur content.
All of MAN’s liquid fuel engines are capable of burning distillated fuels. Of course, our medium speed dual fuel
engines  are capable of burning MFO blended with gas or if gas is not available, in 100% liquid fuel mode. 

 Marine Gas Oil (DMA)

 Property/feature Unit Test method Properties

Density at 15°C min. kg/m3 ISO 3675 820,0

max. kg/m 3
ISO3675 890,0

Cenimatic viscosity/40° min. mm2/s ISO 3104 2

max. mm /s 2
ISO 3104 6,0

Filterability in summer max. °C DIN EN 116 0

in winter max. °C DIN EN 116 -12

Flash point min. °C ISO 1523 60

Content of sediment max. % by weight ISO 3735 0,01

(Extraction method)

Water content max. % by volume ISO 3733 0,05

Sulphur content max. % by weight ISO 8754 1,5

Ash max. % by weight ISO 6245 0,01

Coke residue (MCR) max. % by weight ISO CD 10370 0,10

Cetane number min. - ISO 5165 40

Copper-strip test max. - ISO 2160 1

Hydrogen sulfide max. mg/kg IP 570 2

Acid number max. mg KOH/g ASTM D664 0,5

Oxidation stability max. g/m 3

ISO 12205 25

Lubricity max. µm ISO 12156-1 520

Marine Diesel Oil (DMB)

Property/feature Unit Test method Properties

Density  at 15°C kg/m 3

ISO 3675 < 900

Cinematic viscosity at 40°C mm2/s = cSt ISO 3104 2 - 11

Pour point winter quality °C ISO 3016 <0

summer quality °C <6

Flash point °C ISO 2719 > 60

Sediment content (extraction) % by weight ISO 3735 < 0,1

Water content % by volume ISO 3733 < 0,3

Sulphur content % by weight ISO 8754 < 2,0

Ash content % by weight ISO 6245 < 0,01

Coke residue (MCR) % by weight ISO CD 10370 < 0,30

Cetane number - ISO 5165 > 35

Copper-strip test - ISO 2160 <1

Hydrogen sulfide mg/kg IP 570 2

Acid number mg KOH/g ASTM D664 0,5

Oxidation stability g/m3 ISO 12205 25

Lubricity µm ISO 12156-1 520

All data provided on this site is for information purposes only, explicitly non-binding and subject to changes without further notice.