Maintenance
66
Tightening torques
for screwed
connections
Note the strength class specification for screws, nuts and bolts. Refer
to the table for the corresponding tightening torque. Securely tighten
screws, nuts and bolts to the specified values, provided that no other
value is specified. The torque specifications refer to a dry coefficient
of friction (0.12).
Tighten safety bolts and lock nuts to a 10% higher value.
Specification of strength class
Use the correct screw and bolt tightening torque
Securely tighten screws, nuts and bolts to the specified torques.
Otherwise, damage to the machine and serious or fatal injury may
be caused as a result.
8.8
10.9
12.9
M6
9.9 Nm (7.3 ft.lbs)
14 Nm (10.3 ft.lbs)
17 Nm (12.5 ft.lbs)
M8
24 Nm (17.7 ft.lbs)
34 Nm (25 ft.lbs)
41 Nm (30.3 ft.lbs)
M10
48 Nm (35.4 ft.lbs)
68 Nm (50.2 ft.lbs)
81 Nm (59.8 ft.lbs)
M12
85 Nm (62.7 ft.lbs)
120 Nm (88.6 ft.lbs)
145 Nm (104 ft.lbs)
M14
135 Nm (99.6 ft.lbs)
190 Nm (140 ft.lbs)
230 Nm (166 ft.lbs)
M16
210 Nm (155 ft.lbs)
290 Nm (214 ft.lbs)
350 Nm (258 ft.lbs)
M20
410 Nm (302 ft.lbs)
580 Nm (428 ft.lbs)
690 Nm (509 ft.lbs)
