WinGD WARTSILA RT-flex58T-D, Maintenance Manual

Page: 117 / 498

Maintenance
1903 − 1/A2
RT-flex58T-D
Winterthur Gas & Diesel Ltd.
3/ 5
3. Loosening and tensioning the tie rods
Should tie rods have to be removed or fitted, the following points have to be ob-
served:
⇒ Remove clamp screws 10 (Fig. ’D’).
D
If the tie rods have been newly tensioned, then the elastic studs of the main
bearings also have to be checked for correct pretensioning (see 1132 − 1 ).
D Tensioning has to be carried out in one procedure.
D
The sequence in which the tie rods are to be loosened or tensioned is shown in
Fig. ’B’, i.e. in pairs, first tie rods a/a, then b/b, etc.
Never move pistons 5 of the pre-tensioning jacks further up than to the red limiting
grooves ’BN’ (Fig. ’A’).
3.1 Loosening
The procedure for loosening the tie rods is the same as the one described in sec-
tion 2 ’Checking the pre-tension’, except that pre-tensioning jacks must be turned
back by 3
½
turns after being completely screwed down the pre-tensioning jacks
(gap ’SA’ in Fig. ’A’). At this starting point connect the jacks with hydraulic unit
94942 and operate it until a pressure of approx. 1530 bar is reached.
⇒ Screw back nuts 3 by 3
½
turns with rod 94005F.
⇒ Release pressure to zero and remove the pre-tensioning jacks.
3.2 Tensioning
Preliminary works:
D
Clamp screws 10 must not be tightened up.
D Lower tie rod nut 14 is screwed on.
⇒ Clean the seating surface for intermediate ring 2 and upper tie nut 3 and
smear them with MOLYKOTE G paste.
⇒
Smear the tie rod thread lavishly with MOLYKOTE G paste and screw on up-
per tie nut with the marking TOP upwards (check for easy threading).
⇒ Screw eye bolt into the tie rod and lift it carefully until the lower tie rod nut rests
snugly against the bearing girder.
Risk of accident! Use a manual ratchet hooked onto the crane, with which the tie
rod can be lifted manually until the lower nut is snug on its seating, as with the crane
alone the landing of the nut cannot easily be felt and the rope might break.
⇒ In this position tighten the upper tie rod nut with rod 94005F until firmly seated
on the intermediate ring, and separate the manual ratchet from the tie rod.
There must now be no clearance between bearing girder and lower tie rod nut and
the lower tie rod nut must be flush with the tie rod end (Fig. ’D’).
⇒ Place pre-tensioning jacks GF 94180 onto tie rods a/a .
⇒ Screw pre-tensioning jacks completely down with vent screws 6 open until
there is only little or no clearance at ’x’ (Fig. ’A’).
If necessary, turn the pre-tensioning jack back a little so that the holes in the tie
rod nuts are accessible.
Checking the Pre-tension and Tensioning the Tie Rods with M80x6 Thread Diameter
V2 / 2013
CHECK