... the beginning of winding, and then getting loose, to avoid the problems that the cores are loose from the rolls after ... perforation knife. With 4 perforation blades to make clear perforating. The perforating pitch controlled by gear box.Three backstands, pneumatic jumbo ... 3 HP air compressor, mini pressure 5kg/cm2 Pa(Provided by client)PowerVariable frequency speed control, 7.5KWMachine Size6200×4200× ...