Friction: To ensure the quality of the production line assembly work, and can be controlled and to achieve consistency. You must consider the impact generated by friction joints. As friction screw bearing surface, thread, and gaskets caused. In the process of tightening the screws, usually 90% torque loss due to friction can really tighten the screw axis force torque generated, only 10%.

Impact tool is driven by rotation of the impact hammer spindle body, produce a torque, this design makes hammering group easy to wear, so that the tool life is too short; oil pulse tool is rotated by the hydraulic cylinder, the use of oil pressure generating torque, and therefore the durability of its drive member much longer than the impact tool.

Material: Material decide what type of screws or tightening tool and screwed tight size forces, the most commonly used material for iron, aluminum, plastic and wood, such as different species.