PIERCING ROLLING METHOD OF SEAMLESS STEEL PIPE

摘要

PURPOSE:To produce a seamless steel pipe having high quality with high efficiency by performing piercing while supplying a liquid paint mixture composed of metallic oxide powder and granules and a binder to the circumferential surface of disc roll type guide shoes of an inclined roll piercer. CONSTITUTION:A material 4 to be rolled is pierced while a liquid paint mixture composed of a seizure preventing material consisting of metallic oxide powder and granules and a binder is continuously supplied to and coated on the circumferential surfaces of disc roll type guide shoes 5, 5' provided to face each other with an inclined roll piercer which pierces the material 4 by means of main rolls 1, 1' for rolling which are inclined and positioned to face each other while receiving the restriction from the shoes 5, 5' and a plug 3 and produces a seamless steel pipe. The seizure between the shoes 5, 5' and the material 4 is thereby prevented and the slip between both is suppressed. The seamless steel pipe having high quality without any guide shoe mark is produced with high efficiency.