... purlins, in no need of roller changing.2.PLC CONTROL: The production of hole-punching, cutting-off and roll ... , hydraulic cutter, quick-changed-roller roll-former, electronic control system, hydraulic system, etc.4.DRIVEN METHOD: It ... and converter, under reliable punching position control, speed control and length control.5.ROLL FORMING PRODUCTION PROCESS: Steel Material Coil -- Decoiler -- Manual ...