The machlnes are used for punching shear the cold crimped engine bed with the thickness of 0.4- 6mm the width of 2000mm Material strength of 450N/mm2The specifications of punching shear are su~eyed by the bit of TB5-20 mesh grid plate:if the TB TL are changed the punching shear knife is also changed;TB,TL are increased,the punching shear strength is reduced:TB,TL are reduced,the punching shear strength is increased In order not to damage components for the excess load.