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7
Hold the tool firmly and place the socket over the bolt or
nut. Turn the tool on and fasten for the proper fastening
time.
007461
The proper fastening torque may differ depending upon
the kind or size of the bolt, the material of the workpiece
to be fastened, etc. The relation between fastening
torque and fastening time is shown in the figures.
160
140
120
100
80
60
40
20
0
0
0.5
1.0
1.5
2.0
Standard bolt
N m
(ft lbs)
Fastening torque
Fastening time (S)
Proper fastening torque
M16(5/8")
M14(9/16")
M12(1/2")
(116)
(101)
(87)
(72)
(58)
(43)
(29)
(14)
M16(5/8")
M14(9/16")
M12(1/2")
007538
0
High tensile bolt
N m
(ft lbs)
Fastening torque
Fastening time (S)
Proper fastening torque
160(116)
140(101)
120(87)
100(72)
80(58)
60(43)
40(29)
20(14)
180(130)
200(145)
1.0
2.0
3.0
M14(9/16")
M14
M12(1/2")
M12
M10(3/8")
M10
(9/16")
(1/2")
(3/8")
007537
NOTE:
•
Hold the tool pointed straight at the bolt or nut.
•
Excessive fastening torque may damage the
bolt/nut or socket. Before starting your job, always
perform a test operation to determine the proper
fastening time for your bolt or nut.
•
If the tool is operated continuously until the battery
cartridge has discharged, allow the tool to rest for
15 minutes before proceeding with a fresh battery
cartridge.
The fastening torque is affected by a wide variety of
factors including the following. After fastening, always
check the torque with a torque wrench.
1.
When the battery cartridge is discharged almost
completely, voltage will drop and the fastening
torque will be reduced.
2. Socket
•
Failure to use the correct size socket will cause
a reduction in the fastening torque.
•
A worn socket (wear on the hex end or square
end) will cause a reduction in the fastening
torque.
3. Bolt
•
Even though the torque coefficient and the
class of bolt are the same, the proper fastening
torque will differ according to the diameter of
bolt.
•
Even though the diameters of bolts are the
same, the proper fastening torque will differ
according to the torque coefficient, the class of
bolt and the bolt length.
4.
The use of the universal joint or the extension bar
somewhat reduces the fastening force of the
impact wrench. Compensate by fastening for a
longer period of time.
5.
The manner of holding the tool or the material of
driving position to be fastened will affect the torque.
6. Operating the tool at low speed will cause a
reduction in the fastening torque.
MAINTENANCE
CAUTION:
•
Always be sure that the tool is switched off and the
battery cartridge is removed before attempting to
perform inspection or maintenance.
•
Never use gasoline, benzine, thinner, alcohol or the
like. Discoloration, deformation or cracks may
result.