Design data:
1000 cSt
Viscosity for dimensioning of electric motor
Pressure control valve, booster unit (1V03)
The pressure control valve in the feeder/booster unit maintains the pressure in the de-aeration tank by dir-
ecting the surplus flow to the suction side of the feed pump.
Design data:
Equal to feed pump
Capacity
1.6 MPa (16 bar)
Design pressure
100°C
Design temperature
0.3...0.5 MPa (3...5 bar)
Set-point
Automatic filter, booster unit (1F08)
It is recommended to select an automatic filter with a manually cleaned filter in the bypass line. The auto-
matic filter must be installed before the heater, between the feed pump and the de-aeration tank, and it
should be equipped with a heating jacket. Overheating (temperature exceeding 100°C) is however to be
prevented, and it must be possible to switch off the heating for operation on MDF.
Design data:
According to fuel specification
Fuel viscosity
100°C
Design temperature
If fuel viscosity is higher than 25 cSt/100°C
Preheating
Equal to feed pump capacity
Design flow
1.6 MPa (16 bar)
Design pressure
Fineness:
35
μ
m (absolute mesh size)
- automatic filter
35
μ
m (absolute mesh size)
- by-pass filter
Maximum permitted pressure drops at 14 cSt:
20 kPa (0.2 bar)
- clean filter
80 kPa (0.8 bar)
- alarm
Flow meter, booster unit (1I01)
If a fuel consumption meter is required, it should be fitted between the feed pumps and the de-aeration
tank. When it is desired to monitor the fuel consumption of individual engines in a multiple engine installation,
two flow meters per engine are to be installed: one in the feed line and one in the return line of each engine.
There should be a by-pass line around the consumption meter, which opens automatically in case of ex-
cessive pressure drop.
If the consumption meter is provided with a prefilter, an alarm for high pressure difference across the filter
is recommended.
De-aeration tank, booster unit (1T08)
It shall be equipped with a low level alarm switch and a vent valve. The vent pipe should, if possible, be led
downwards, e.g. to the overflow tank. The tank must be insulated and equipped with a heating coil. The
volume of the tank should be at least 100 l.
Circulation pump, booster unit (1P06)
The purpose of this pump is to circulate the fuel in the system and to maintain the required pressure at the
injection pumps, which is stated in the chapter Technical data. By circulating the fuel in the system it also
maintains correct viscosity, and keeps the piping and the injection pumps at operating temperature.
When more than one engine is connected to the same feeder/booster unit, individual circulation pumps
(1P12) must be installed before each engine.
64
Product Guide Wärtsilä 34DF - 3/2012
Product Guide
6. Fuel System
