WinGD X72DF, Installation Manual

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Marine Installation Manual 2021-08 4-83
4 Ancillary Systems
4.7 Air supply system
X72DF
4.7.1 Capacities of air compressor and receiver
The capacity of the air compressor and receiver depends on the total inertia ( J
tot
)
of the propulsion system’s rotating parts.
•
Total inertia = engine i shafting and propeller inertia
1)
:
•
Engine inertia ( J
eng
): refer to GTD
2)
•
Relative inertia:
4.7.2 System specification
Starting air compressors
The discharge air temperature must not exceed 90 °C and the air supply to the
compressors is to be as clean as possible without oil vapour.
Starting air receivers
1) Propeller inertia includes the part of entrained water.
2) The
GTD application enables the capacities of compressors and air receivers to be op -
timised for the inertia of the engine and shaft line.
tot eng
S P
J J J
+
= +
tot
rel
eng
J
J
J
=
Capacity Refer to GTD .
Delivery gauge pressure 25 or 30bar
Type Fabricated steel pressure vessels with domed ends and inte -
grated pipe fittings for isolating valves, automatic drain valves,
pressure reading instruments and safety valves
Capacity Refer to GTD .
Working gauge pressure 25 or 30bar