High frequency welding uses solid resistance heat as energy source. During welding, the resistance heat generated by high-frequency current in the workpiece heats the surface of the workpiece welding area to a molten or nearly plastic state, and then imposes (or does not impose) the forging force to achieve the metal combination.

The cross shaft is also called ten-byte universal joint. The English name is universal joint. It is a part that realizes variable-angle power transmission. It is used to change the position of the transmission axis. It is the universal transmission device of the automobile drive system.