GE PHI 530.1425.2500 Operating And Maintenance Instructions Manual page 13

Bolts and nuts of the lifting tools must be tightened at torque values listed in the following Table 7.
To lift and install the bushings on the transformer the lifting crane shall have the following minimum
characteristics:
Solution with one overhead crane
• Single grinder crane.
• Crane capacity ≥ 2.5 t.
• Hoist lifting height ≥ 12m.
• Slow hoisting speed ≤1.3 m/min.
Or, as an alternative:
N. 1 mobile telescopic crane with the following technical characteristics:
• Single crane.
• Lifting boom working length ≥ 17m.
• Hoist lifting height ≥12m.
• The capacity of the crane must comply with the characteristics indicated in with the following Figure 6.
The crane operative working conditions must be within the limits set by the red area.
HVDC TRANSFORMER BUSHINGS
Screw / nut
type
M12
M24
M30
Table 7 – Screws and nut tightening torques
Figure 6 – Mobile crane working characteristics
PHI 530.1425.2500
PHI 265.850.1500
Kepco project
Tightening
Torque
[Nm]
60
229
460
IS 2664 GB
Page 13 of 70