heat treated in order to obtain high hardness. cold rolling processing the thread ends to achieve good pressure-bearing ability, anti wearing out and longer life-span. thread phosphor or copper coated to achieve good resistant-wearing ability and anti-thread gluing ability. screw thread numerical controlled...
heat treated in order to obtain high hardness. cold rolling processing the thread ends to achieve good pressure-bearing ability, anti wearing out and longer life-span. thread phosphor or copper coated to achieve good resistant-wearing ability and anti-thread gluing ability. screw thread numerical controlled...