The metal shredder mainly relies on the principle of “shear and cut” to complete the process of crushing scrap metal. The motor drives the reducer to transmit the torque to the movable knife of the crusher through the knife roller shaft, and the knife hook of the movable knife hooks the material down. Tear, the blade of the opposite roller cuts up solid waste like scissors, and the crushed materials and pre-screened materials are discharged from the bottom of the crusher.