The standards of Flange Nut include national standard GB (GB/T), German standard (DIN), British standard (BS), and Japanese standard (JB). A weld nut is a nut suitable for welding outside the nut. It is generally made of weldable materials and is thicker and suitable for welding. Welding is equivalent to turning two separate parts into a whole, melting the metals at high temperature and then mixing them. After cooling together, the alloy will be added in the middle, and the internal force is the effect of molecular force, and the strength is generally greater than that of the parent body [1]. The experiment of welding parameters depends on the fusion size of the weld, and the welding parameters are adjusted according to the fusion size until the defects are eliminated. Of course, the quality of welding is related to the pre-welding treatment, such as dust removal, oil stains, etc.

It is used in conjunction with bolts and screws to connect and fasten parts. Among them, I-type carbon steel hex nuts are widely used, and C-grade nuts are used for machines, equipment or structures with rough surfaces and low precision requirements; A-grade and B-grade nuts are used for relatively smooth surfaces and high precision requirements. machinery, equipment or structures. Type II carbon steel hex nuts have a thicker thickness m, and are mostly used in occasions that often need to be assembled and disassembled. The thickness m of the carbon steel hex nut is relatively thin, and it is mostly used in occasions where the surface space of the connected parts is limited. Carbon steel hexagon nuts are fasteners with internal threads and used in conjunction with bolts.