English
15
M12
×
45
kgf·cm
1200
1000
800
600
400
200
0
N·m
120
100
80
60
40
20
0
0 1 2 3
M10
×
30
kgf·cm
1000
800
600
400
200
0
N·m
100
80
60
40
20
0
0 1 2 3
M8
×
30
kgf·cm
1000
800
600
400
200
0
N·m
100
80
60
40
20
0
0 1 2 3
Tightening torque
Tightening torque
Tightening torque
Tightening time: sec.
(Steel plate thickness
t = 10 mm)
Tightening time: sec.
(Steel plate thickness
t = 25 mm)
Tightening time: sec.
(Steel plate thickness
t = 25 mm)
1400
1200
1000
800
600
400
200
0
140
120
100
80
60
40
20
0
M14
×
50
0
1
2
3
kgf·cm
N·m
1400
1200
1000
800
600
400
200
0
140
120
100
80
60
40
20
0
M12
×
45
0
1
2
3
kgf·cm
N·m
1000
800
600
400
200
0
0
1
2
3
100
80
60
40
20
0
M10
×
30
kgf·cm
N·m
Ordinary bolt
High tension bolt
Ordinary bolt
High tension bolt
High tension bolt
Ordinary bolt
Fig. 22
For WH12DM2
(5) Using optional parts (WR12DM2, WR9DM2)
The tightening torque is reduced a little when an
extension bar, universal joint or a long socket is
used.
(6) Clearance of the socket (WR12DM2, WR9DM2)
A worn or deformed hex. or a square-holed socket
will not give an adequate tightness to the fitting
between the nut or anvil, consequently resulting in
loss of tightening torque.
Using an improper socket which does not match to
the bolt will result in an insufficient tightening torque.
Matching socket and bolt sizes are shown in
Table 1,
2, 3
and
4
.
(7) Tightening torque varies, depending on the battery’s
charge level. (WR12DM2, WR9DM2)
Fig. 28
and
29
show examples of the relationship
between tightening torque and the number of
tightenings, for WR12DM2 and WR9DM2. As shown,
tightening torque gradually weakens with the increase
in the number of tightenings. In particular, as the
torque decreases very close to the complete discharge
(“a” margin in graph), the unit’s impact weakens, the
number of time impacts declines and tightening
torque drops off abruptly. If this occurs, check torque
level, then recharge the battery if necessary.
For WH9DM2
Tightening time: sec.
(Steel plate thickness
t = 10 mm)
Tightening time: sec.
(Steel plate thickness
t = 25 mm)
Tightening time: sec.
(Steel plate thickness
t = 25 mm)
Tightening torque
Tightening torque
Tightening torque
High tension bolt
High tension bolt
Fig. 23
High tension bolt
Ordinary bolt
Ordinary bolt
