WÄRTSILÄ RT-flex50-D, Руководство по обслуживанию

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Maintenance
3403−1/A1
RT-flex50-D
Wärtsilä Switzerland Ltd
8/ 8
5.1 Fitting
⇒
Turn crank of the cylinder concerned to T.D.C.
⇒
Slightly lift piston by crane. Loosen screwed con-
nections 14 (Fig. ’F’) and push both supports 10
outwards. Then lift the piston including piston rod
gland 12 so far that the two hinged covers 11 can
be turned up.
⇒
Bring the piston over the cylinder liner and then
slowly lower it (Fig. ’I’).
D
When the piston is lowered into the cylinder liner
until the lowest piston ring is at the upper level of
the insertion funnel, arrange the piston rings so
that their gaps alternate by 180
_
to each other (see
3425−1 ).
⇒
Slowly lower the piston further till its piston rod foot
has arrived just above the crosshead pin. While
one person directs the further lowering of the pis-
ton from the top, another directs the piston rod
progress from the engine interior and how it must
be turned to guide the piston rod foot, without jam-
ming, into centring pins 6 (Fig. ’A’) in the crosshead
pin.
⇒
Slacken the crane rope a bit and remove the sus-
pension device.
⇒
Turn piston to B.D.C. (loosen crane correspond-
ingly) and direct the insertion of the piston rod
gland into its seating bore in the cylinder block (see
2303−1 ).
⇒
Loosen and remove both distance holders from
the piston foot.
⇒
Firmly tighten all screws fastening the piston rod
gland housing.
⇒
Tension waisted studs 3 for the piston foot fasten-
ing as described in section 3.
⇒
Refit the antipolishing ring (see 2124−2 ).
I
018.391/09
94342
94345
6. Leak test
A leak test must be carried out after every fitting of a piston in the cylinder. For this,
start the bearing lubrication pump and set the bearing lubricating pressure. Check
through the scavenge space on the fuel side in the cylinder block (piston under-
side) whether cylinder liner running surface and piston rod remain dry.
Any increase in the dirty oil level in the scavenge air space may be caused by a
faulty O-ring in the piston.
2010 / 50−D
Piston: Removal and Fitting