MAN B&W L28/32H, Руководство пользователя

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B 14 00 0
Further, the system is equipped with an emergency
starting valve which makes it possible to activate the
air starter manually in case of a power failure.
Safety System
As standard the engine is equipped with a pneuma-
tically/mechanically overspeed device, which starts
to operate if the maximum permissible RPM is ex-
ceeded. This device is fitted to the end cover of the
engine driven lubricating pump and is driven from the
pump through a resilient coupling.
When the maximum permissible RPM is exceeded,
the overspeed device will activate a pneumatically
controlled stop cylinder, which will bring the fuel
index to zero and stop the engine.
A microswitch will be activated too and give a stop
signal to the safety system.
Pneumatic Start Sequence
When the starting valve is opened, air will be sup-
plied to the drive shaft housing of the air starter.
The air supply will - by activating a piston - bring the
drive pinion into engagement with the gear rim on the
engine fly wheel.
Compressed Air System
L28/32H
99.34
1613520-6.4
Page 2 (2)
When the pinion is fully engaged, the pilot air will flow
to, and open the main starting valve, whereby air will
be led to the air starter, which will start to turn the
engine.
When the RPM exceeds approx. 140, at which firing
has taken place, the starting valve is closed whereby
the air starter is disengaged.
Optionals
Besides the standard components, the following
standard optionals can be built-on:
– Main stop valve, inlet engine
Pressure transmitting
– PT 70 Compressed air inlet
Position switching, stop
– ZS75 Microswitch on flywheel
Data
For air consumption pr. start, see D 10 05 0 "List of
Capacities".
Operating levels and set points, see B 19 00 0, "Ope-
rating Data and Set Points.