MAK M20, Руководство по эксплуатации

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Regulations and care
Heavy fuels
A4.05.07.02
M20-M601C
en / 15.12.1997 BA000170 1/5
Ĺ
Heavy fuels
(Viscosity in mm
2
/s (cSt) at 100 °C, in the past at 50 °C)
All fuels are called heavy fuels that consits in the main of residual oils from oil refining.
General Requirements:
The fuel must represent a homogenous mixture of hydro-carbon coming from the mineral oil pro-
cessing. The fuel must not contain other substances (e. g. mineral acids, alcali) if not explicitely
noted in the specification. Minor quantities of additives to improve special fuel properties are per-
mitted.
Depending on whether it is the highest available viscosity or a mixture with distillates to obtain the
required viscosity, the following designations are still used a lot at the present:
Bunker Fuel Oil (BFO)
Marine Fuel Oil (MFO)
Bunker C Fuel
Intermediate Fuel
(IF)
Light Fuel Oil (LFO)
Thin Fuel Oil (TFO)
Various organizations, such as:
BSI – British Standards Institution
CIMAC – Conseil International des Machines à Combustion
ISO – International Organisation for Standardisation
are busy to find internationally applicable limit value specifications for marine fuels, especially for
heavy fuel oils, and because of their activities new designations will be introduced to describe fuel
properties.
ISO-Specification (ISO 8217)
The ISO-Specification for Marine Fuels was issued in April 1987.
A revised edition was published in March 1996.
A classification according to quality characteristics and viscosities was introduced.
The classes difer from
ISO-F-RM
1)
A
2)
10
3)
(before, e. g. IF 30 with satisfactory data)
up to
ISO-F-RM H 55 (before, e. g IF 700 with in case using the maximum limit
values)
1)
RM = Residual Marine
2)
Quality classification
3)
Max. viscosity at 100 °C (mm
2
/s)
(see A4.05.07.05 ).