The hexagon socket head screw is usually composed of a hexagonal socket head screw, and the elastic washer of the socket socket cup head screw and the flat washer combination screw are fastened together. General material is 8.8. The main factory uses silk thread 10B21 for production. Hardness up to 8.8, but requires dehydrogenation to prevent gasket and socket head cap bolts from breaking.

Some are classified as iron and stainless steel. 10101018~10B21 etc. are generally used for the inner hexagon combined spiral wire. 10B21 is used to make 8. 8 combination screws. Just like 8.8 hexagon socket head combination screws, commonly used 10B21 wire. After heat treatment, hydrogen gas is removed and electroplating. This is to prevent the hexagon socket head combination screw pad from breaking. Stainless steel combination screw, generally refers to stainless steel SUS 304. SUS 201 combination screws are generally done very little. Due to the poor hardness control of 201 stainless steel threads, cracks are prone to occur. Hexagon combination screws are used to connect thin metal sheets. When connecting, make a threaded bottom hole for the connector, and then screw the hex combination screw into the threaded bottom hole of the connector. Due to the high surface hardness of the combined screw thread, the internal thread can be separated from the threaded bottom hole of the connector, and is mainly used in railways, highway bridges, boiler steel structures, industrial plants, high-rise civil buildings, tower structures, hoisting machinery and Its steel structure requires the use of friction high-strength socket head cap screws. A special electric wrench should be fitted with upper and lower sockets, one on the hexagon of the nut and the other on the ten corners of the socket head cap screw. When tightening, a clockwise force distance is applied to the nut and a counterclockwise force distance is applied to the dodecagon body of the bolt, so that the end of the combination socket head cap screw and dodecagon body is connected to the neck to withstand torsional shear, Installation is complete until the neck shears break.