φ50mm THREE-ROLL PIERCING-ROLLING MILL FOR SEAMLESS STEEL PIPES

The paper describes the process and technological characteristics of a φ50mm piercing-rollingmill for seamless pipes developed by Taiyuan Heavy Machinery Institute.The employment of the millmakes it possible to hot-roll steel pipes with wall-thickness tolerances of ±4~5.8% and with ODtolerances of ±0.4~0.51% through only one operation procedure as piercing-rolling.