00-6
OVERVIEW
TIGHTENING TORQUE
Tightening Torque
The common tightening torque is shown in the list.
Tightening torque of special parts is shown at the beginning of each group.
Tightening torque of bolts and nuts
Thread Dimension
Torque (Kg. M)
Light alloy
Cast iron, steel
NPTF
1/16
0.5
0.8
0.8
1.2
PT
1/8
0.8
1.2
1.5
2.2
PT
1/4
2.0
3.0
3.5
4.5
NPTF
1/4
2.0
3.0
3.5
4.5
PT
3/8
4.0
5.5
5.5
7.5
PT
1/2
7.0
10.0
12.0
16.0
Tightening torque of taper thread
Torque (Kg. M)
Bolt (with spring washer)
Valve bolt
Head mark 4
Head mark 7
Head mark 10
Head mark 4
Head mark 7
M6
1.0
0.9
1.3
1.1
M8
1.25
1.1
1.8
3.0
1.4
2.4
M10
1.25
2.0
3.4
6.0
3.0
5.0
M12
1.25
3.6
6.2
10.8
5.5
9.0
Diameter
of bolt
Thread
pitch
