2.1 BASIC OPERATION
2.1.2 TORQUE CONTROL FUNCTION
The tightening torque for the work target is calculated by the torque sensor of the tool.
When the calculated torque value reaches the preset target value, the tool is supposed to
stop (shut off) automatically.
(For how to set the Shut-Off Torque,
WARNING
Make a daily management of torque performance.
Otherwise, bolts will be loosened by torque change, causing an accident.
CAUTION
• During work, the trigger switch should be pulled all the way in. If the trigger switch
is not pulled in enough, torque control will not function and the tool will not stop
automatically.
• At work where a load on the way is higher than the target torque, bolts may not be
tightened up because the load on the way is judged to be the target torque.
• At work where members vary, the tightening torque may vary even at the same set
torque.
• If you tighten the same bolt twice, overtightening may cause the bolt to break or the
bolted member to deform.
• The tightening torque varies with the work conditions. Adjust it in the actual work.
• The bolt tightening torque might change according to the following factors.
Bolt
Socket
Condition of
member to
tighten
Working
method
EN
Refer to 2.2.8
Bolt diameter (generally, as the diameter becomes large, the
tightening torque will increase), torque coefficient (shown by the bolt
manufacturer), grade, length, washer presence and type, etc.
Length, quality of material, deterioration degree, use of universal
joint, use of socket adapter, use of extension socket, etc.
Quality of material, bearing surface finish, etc.
How you put the tool to a bolt, force that holds the tool, how you pull
the trigger switch, etc.
.)
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