Hitachi WR 12DM - Manual (Page 14)

13
English
Tightening torque
Number of tightenings (PCS)/charging
kgf•cm
1600
1200
800
400
0
0 20 40 60 80 100 120 140
N•m
160
120
80
40
0
a
When full recharged
When completely discharged
Explanation of strength grade:
4 — Yield point of bolt: 320 N/mm 2 {32.6 kgf/mm 2 }
8 — Pulling strength of bolt: 400 N/mm 2 {40.8 kgf/mm 2 }
* The following bolt is used.
Ordinary bolt: Strength grade 4.8
High tensile bolt: Strength grade 12.9
(
Bolt
Nut Fig. 18
Steel plate thickness t
)
Tightening time: sec
(Steel plate thickness
t = 10 mm)
Tightening time: sec
(Steel plate thickness
t = 10 mm)
Tightening time: sec
(Steel plate thickness
t = 25 mm)
M8
×
30 kgf•cm
800
600
400
200
0
N•m
80
60
40
20
0
0 1 2 3
High tension bolt
Ordinary bolt
M10
×
30 kgf•cm
1000
800
600
400
200
0
N•m
100
80
60
40
20
0
0 1 2 3
High tension bolt
Ordinary bolt
M12
×
45
kgf•cm
1000
800
600
400
200
0
N•m
100
80
60
40
20
0
0 1 2 3
High tension
bolt
Ordinary bolt
Fig. 17
Fig. 19
M16
×
55 F10T (tighening time 3 sec)
Tightening torque
Tightening torque
Tightening torque