Tube shell for manufacturing a seamless steel pipe and a method for its manufacture

摘要

A pierced shell of an austenitic stainless steel having a good inner surface condition is provided, and a means is established which can perform mass production on an industrial scale of a good quality seamless steel pipe of stainless steel. An austenitic stainless steel billet with a P content of at most 0.040% and an S content of at most 0.020% is pierced under conditions such that the pipe expansion ratio H (outer diameter of shell/diameter of billet to be worked) satisfies the following equation to obtain a tube shell of an austenitic stainless steel. {P(%)/(0.025xH-0.01)}²+{S(%)/(0.015xH-0.01)}²<=1 When manufacturing a seamless steel pipe of an austenitic stainless steel, the above-described shell is rolled to form a pipe.