use

Steel structure with high strength large  combination screw, mainly used in railway and road Bridges, boiler steel structure, industrial plants, high-rise civil buildings, tower mast structure, lifting machinery and steel structure need to use friction type high strength bolt combination screw occasions. It is characterized by a bolt, which is also called a dodecagon at the end of the bolt. When installing, a special electric wrench must be used, which has two socket heads above and below, one set on the hexagon body of the nut, and the other set on the ten corner body of the outer hexagon screw. 

When tightening, apply a clockwise torque to the nut and an equal counterclockwise torque to the dodecagon body of the bolt, so that the connecting neck between the end of the outer hexagonal screw and the dodecagon body is subjected to torsion shear until the neck is cut, and the installation is finished. This torsional high-strength outer hexagonal screw is a one-time screw, which can not be removed after installation.

Scope of application

In general, the combination of  is widely used in electrical, electrical, mechanical, electronic, household appliances, furniture, boats and so on. But it says that different combinations of screws have different functions. For example, cross pan head combination screws are generally used in small electronic products. The larger cross hexagon combination screws are used in larger electrical products, such as frequency converters, and many cross hexagon combination screws are useful in some large frequency converters. Hit on the inverter housing. 

To loosen the tightening action. In the case of two combination screws with flower teeth, this is used in the frequency converter, the role is used to break the paint, so that the two combination screws on the shell surface are all energized. There are such as the square pressure line two combination screw, which is itself a pan head screw with a square pad two combination screw. It is generally used on the surface of the terminal. It's for wiring, for pressing wires.