4 Installation
4.4
General Instructions for Installation
For assembling the circuit-breaker use only the bolts supplied. Spare bolts are included in the accessories pack,
in case any are lost during assembly work.
WARNING
If unsuitable bolts are used, they can malfunction and cause severe personal injury.
If the number of bolts supplied for the pressure vessels is insufficient, spare bolts must be ordered from
the factory only.
Grease the threads of all hot-galvanized bolts with Molykote Longterm 2 plus.
Attention
Unchecked tightening can result in damage to or loosening of bolt joints.
Use torque wrench for assembly. Tightening torque see Table 11.
Bolts are of 8.8 grade or higher.
i.e. Minimum tensile strength 800 N/mm2 Minimum yield strength ReH = 640 N/mm2
Screwed joint
Tightening torque
M6
8 + 1 Nm
M8
20 + 2 Nm
M10
40 + 4 Nm
M12
70 + 7 Nm
M16
170 + 20 Nm
M20
340 + 30 Nm
M24
600 + 60Nm
Table 11
Tightening torques required for screw joints
Screw on all union nuts with a tightening torque of 40 ± 4 Nm.
Differing torques are indicated in the text.
Any locking washers and gaskets loosened or exposed during assembly must be replaced.
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