Today, advanced manufacturing represented by large aircraft, large power generation equipment, automobiles, high-speed trains, large ships, and large complete sets of equipment has entered an important development direction. As a result, fasteners will enter an important stage of development. High-strength bolts are used for the connection of important machinery. Repeated disassembly or various installation torque methods require extremely high-strength bolts.
Therefore, the surface condition and thread accuracy will directly affect the service life and safety of the host. In order to improve the coefficient of friction and avoid corrosion, seizure or jamming during use, the technical requirements stipulate that the surface should be treated with nickel-phosphorus plating. The thickness of the coating is guaranteed to be within the range of 0.02～0.03mm, and the coating is uniform, dense and without pinholes.
Heavy hex bolts must be quenched and tempered according to technical requirements. Heat treatment and tempering is to improve the comprehensive mechanical properties of fasteners to meet the specified tensile strength value and yield ratio of the product. The heat treatment process has a vital influence on high-strength fasteners, especially its internal quality. Therefore, to produce high-quality high-strength fasteners, advanced heat treatment technology and equipment are necessary.https://www.ydfastener.com/product/bolts/