Abstract: Since the safety device functions as a necessary protective measure for the MPM with a mechanical feeding roll structure,its reasonableness and operation stability directly affect the safe running of the rolling mill proper and the maintenance costs for the equipment and the product yield as well.Addressing the existing problems of the MPM safety device,design modification of the structure thereof is conducted,involving changing the protective breaking type of the safety block from the original tensile failure into shearing failure.The operational effectiveness of the modified safety device is satisfactory