Maintenance And Inspection - Hitachi Koki WH 12DM2 Instrucciones De Manejo

Bolt
Nut
For WR12DM2
For WR9DM2

MAINTENANCE AND INSPECTION

1. Inspecting the driver bit (WH12DM2, WH9DM2,
WH12DMR)
Using a broken bit or one with a worn out tip is
dangerous because the bit can slip. Replace it.
2. Inspecting 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. Pay attention to wear of a
socket holes periodically, and replace with a new one
if needed.
Steel plate thickness t
kgf·cm N·m
M16 × 55 F10T (tighening time 3 sec)
2000 200
1600 160
1200 When full recharged
120
When completely
800 80 discharged
400 40
0 0
0 20
Number of tightenings (PCS)/charging
M14 × 50 High tension bolt
kgf·cm
N·m
(tightening time 3 sec)
160
1600
120
1200
When full recharged
80
800
When completely
400
40
discharged
0
0
0 20 40
Number of tightenings (PCS)/charging
*The following bolt is used.
Ordinary bolt: Strength grade 4.8
High tensile bolt: Strength grade 12.9
(
Explanation of strength grade:
4 — Yield point of bolt: 32 kgf/mm
8 — Pulling strength of bolt: 40 kgf/mm
Fig. 27
a
40 60 80 100 120
Fig. 28
60 80 100 120
Fig. 29
3. Inspecting the mounting screws
Regularly inspect all mounting screws and ensure
that they are properly tightened. Should any of the
screws be loose, retighten them immediately. Failure
to do so may result in serious hazard.
4. Maintenance of the motor
The motor unit winding is the very "heart" of the
power tool.
Exercise due care to ensure the winding does not
become damaged and/or wet with oil or water.
140
a
140 160
English
)
2
2
16