MAN B&W L28/32H, Manual

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08028-0D\H5250\94.08.12
98.33
Description
The fuel changing system consist for GenSet of two
three-way valves (V1 and V2) with a electric/
pneumatically operated actuator of the simplex type
with spring return and a common valve control box
for the total GenSet plant.
The system facilitates a flexible selection of MDO
and HFO-operating at any load condition. This sy-
stem gives the advantage of individually choosing
MDO or HFO mode of operation of the GenSets.
General
HFO/MDO Changing Valves (V1 and V2) E 11 10 1
1624467-7.2
Page 1 (2)
To maintain recirculation in the HFO flow line when
the GenSet is operated on MDO a by-pass valve
must be installed between the inlet changing valve
(V1) and the outlet valve (V2) at each GenSet as
shown in fig. 1.
Valve Control Box
Electrical power supply to the valve control box is
380 Volt - 50 Hz, or 440 Volt - 60 Hz, depending on
the plant specification, and is established in form of
a single cable connection from the switchboard.
PI
Filter
MDO
Valve V2
Outlet engine Inlet engine
HFO HFO
Valve V1
MDO
Reduction
valve
Water trap
Valve con-
trol box
Air pressure: 6 bar
Air consumption
per stroke : 1.1 litre
ø6 ø6
*
*
*
*
MAN B&W Supply
A1 A2
Due to a built-in transformer, the power supply
voltage will be converted to a 24 Volt DC pilot voltage
for serving the relays, contactors, and indication
lamps. The three-way valves should be placed as near as
possible to the engines. The control box can be
placed in the engine room or in the engine control
room.
Fig. 1 Pneumatic diagram for 3-way changing valves V1 & V2.