WinGD WARTSILA RT-flex58T-D, Maintenance Manual

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Maintenance
9403 − 4/A1
RT-flex58T-D
Winterthur Gas & Diesel Ltd.
3/ 6
2. Working procedure for loosening
2.1. Loosening procedure − > jack with limiting groove
⇒ Thread the jack with opened vent screw 4 onto the extending thread end of
bolt 5 to be loosened until it is landed on the part and piston 2 on cylinder 1 if
possible without clearance at ’x’.
⇒ Reset, i.e. turn the jack correspondingly back (see table).
D
The clearance ’SA’ thus obtained between jack and landing surface of the part
or piston and cylinder is essential. It enables the loosening of the nut until total
relaxation of the bolt in one single working sequence.
⇒ Shut relief valve (’EV’) at the HP oil pump.
⇒ Connect the jack to the HP oil pump or hydraulic unit and actuate the latter.
Close vent screw 4 as soon as oil flows out bubble-free.
⇒ Slowly raise the pressure approx. 20...30 bar beyond the nominal pressure
(see table). The nut is now slack, loosen it correspondingly with round bar
’RS’, while keeping the pressure constant.
Never move piston 2 of the pre-tensioning jack further up than to the red limiting
groove ’BN’.
⇒ Release the pressure at HP oil pump or hydraulic unit to zero and remove the
jack.
PRE-TENSIONING JACK SCREWED ON FOR
TENSIONING LOOSENING
A
016.696/08
x
4
3
KO
RS
5
6
BN
SA
2
1
2013
Hydraulic Pre-tensioning Jacks: General Application Instructions Jack with Limiting Groove