Sumitomo Metal Industries, Inc.

Tsuneo Kondo

Kazuhiro Shimoda

Tomio Yamakawa

Hiroyuki Semba

Hirofumi Hori

K Shimoda

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(%)/(0.025&#xd7;H&#x2212;0.01)}+{S(%)/(0.015&#xd7;H&#x2212;0.01)}&#x2266;1. When manufacturing a seamless steel pipe of an austenitic stainless steel, the above-described shell is rolled to form a pipe.

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Wakayama, Japan

Tsuneo Kondo