2)Tightening time
Longer tightening time results in increased tightening torque. Excessive tightening, how- ever, adds no value and reduces the life of the tool.
3)Different bolt diameters
The size of the bolt diameter affects the tight- ening torque.
Generally, as the bolt diameter increases, tightening torque rises
4)Tightening conditions
•Tightening torque will vary, even with the same bolt, according to grade, length, and torque coefficient (the fixed coefficient indi- cated by the manufacturer upon produc- tion).
•Tightening torque will vary , even with the same bolting material (e.g. steel), accord- ing to the surface finish.
•Torque is greatly reduced when the bolt and nut start turning together.
5)Socket play
•Torque is lowered as the
6)Switch (Variable speed control trigger) Torque is lowered if the unit is used with the switch not fully pulled out.
7)Effect of Connecting Adaptor
The tightening torque will be lowered through the use of a universal joint or a connecting adaptor.
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