WÄRTSILÄ WARTSILA 20, Product Manual

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The diameter of the pipe between the fine filter and the engine should be the same as the
diameter before the filters.
Design data:
according to fuel specifications Fuel viscosity
50°C Design temperature
Larger than feed/circulation pump capacity Design flow
1.6 MPa (16 bar) Design pressure
37
μ
m (absolute mesh size) Fineness
Maximum permitted pressure drops at 14 cSt:
20 kPa (0.2 bar) - clean filter
80 kPa (0.8 bar) - alarm
6.3.5.5 Pressure control valve, MDF (1V02)
The pressure control valve is installed when the installation includes a feeder/booster unit for
HFO and there is a return line from the engine to the MDF day tank. The purpose of the valve
is to increase the pressure in the return line so that the required pressure at the engine is
achieved.
Design data:
Equal to circulation pump Capacity
50°C Design temperature
1.6 MPa (16 bar) Design pressure
0.4...0.7 MPa (4...7 bar) Set point
6.3.5.6 MDF cooler (1E04)
The fuel viscosity may not drop below the minimum value stated in Technical data. When
operating on MDF, the practical consequence is that the fuel oil inlet temperature must be
kept below 45°C. Very light fuel grades may require even lower temperature.
Sustained operation on MDF usually requires a fuel oil cooler. The cooler is to be installed in
the return line after the engine(s). LT-water is normally used as cooling medium.
If MDF viscosity in day tank drops below stated minimum viscosity limit then it is recommended
to install an MDF cooler into the engine fuel supply line in order to have reliable viscosity
control.
Design data:
1 kW/cyl Heat to be dissipated
80 kPa (0.8 bar) Max. pressure drop, fuel oil
60 kPa (0.6 bar) Max. pressure drop, water
min. 15% Margin (heat rate, fouling)
50/150°C Design temperature MDF/HFO installa-
tion
6-20 Wärtsilä 20 Product Guide - a13 - 6 September 2016
Wärtsilä 20 Product Guide 6. Fuel Oil System