Winterthur Gas X40-B, Maintenance Manual

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Maintenance
2751 − 4/A1
Winterthur Gas & Diesel Ltd.
1/ 2
Exhaust Valve
Grinding the Seating Surface on the Valve Head
Tools:
1 Feeler gauge 94122
1 Valve grinding device 94291
1 Gauge 94292
1. General
Grinding in a valve together with its valve seat with grinding paste is not per-
mitted.
Valves which have had the seating surfaces badly damaged by pitting or corrosion have
to be reground by machine. It is strongly recommended that a suitable grinding device
94291 be made available.
Note: A valve spindle with missing rotation wing may not be reground. The wing
hub must be shrink-fitted on the valve shaft by heating it to 480 _ C. Grinding
may first begin after the whole unit has cooled down.
The devices from the makers ’HUNGER’ and ’CHRIS - MARINE’ are well proven for
valve grinding and can also be ordered directly from Wärtsilä Services Switzerland Ltd.,
Winterthur.
2. Grinding the seating surface
D
Only as little material as necessary
should be ground off the valve seating
surface to provide a clean and smooth
finished surface.
Only grind with cooling (wet).
D In order to avoid the appearance of
chatter marks on the seating surface,
the grinding machine should be placed
in an area which is free of vibration from
running machinery or engines, etc. If
necessary the grinding machine should
be stood on a rubber mat.
Note: For the application of the grinding
device refer to the operating
instructions.
2016
SEATING SURFACE ANGLE ON VALVE
a
016.744/08
+4’
a = 30 _
+6’
94291
EXAMPLE DRAWN WITH PNEUMATICAL-
LY POWERED DEVICE FROM CHRIS-MA-
RINE
Fig. 1