What is torque electric screwdriver

First of all to explain, to tighten a screw torque is not needed to by a screwdriver to determine (whether it is electric or pneumatic or manual), but by the screw (or nut, same below) itself, tighten the target and condition to determine.

Screw factors mainly consider screw size, length, screw material;

Tighten the objective factors mainly consider the target size (mainly the thickness), the target material;

Working condition of factors to consider when using the temperature, humidity, vibration condition, and so on.

The above factors should be considered, so there is no unified calculation formula can be applied, for example: with M2.5 screw two pieces of thickness of 2 mm plate, a kind of screw is 12.9, is 45 # steel plate, screw is 4.8, and another case board is PVC printing plate. The tightening torque may be 2 ~ 3 times!

If you screw is 12.9, need to tighten the artifact is steel or similar material, and use condition is mild, moderate, then tighten the cow moment about 1 + / - 0.1 N.M