WÄRTSILÄ RT-flex50-D, Maintenance Manual

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Maintenance
2751−3/A1
RT-flex50-D
Wärtsilä Switzerland Ltd
5/ 5
5. Checking the valve seat
After grinding it is necessary to check whether the new or
re-ground valve makes correct contact with the valve
seat. For this the spindle head seat face is spread with a
thin coating of blueing paste, then inserted vertically into
the valve guide bush.
Remark: The angle difference is chosen such that in the
hot operating condition the valves makes contact by
50 −100% from the outer edge (Fig. ’F’). The blueing
check should show that the cold valve makes contact
only from inside around the whole circumference. The
angle difference can be checked at gap ’S’ on the outer
edge with a feeler gauge (Fig. ’G’).
⇒
The blueing on the valve seat must be checked by
tapping the valve head three or four times with a
hammer on a wooden block! (Fig. ’E’).
Do not rotate the valve spindle on the valve seat
face, as this risks seizure of the seating.
CHECK
F
G
30
2’ +
0
_
HA RC
E
50−100%
003.455/00
003.456/00
003.457/00
S = 0.029 − 0.048 mm
Exhaust Valve: Replacing and Grinding the Valve Seat
2010