摘要 |
A thread joint capable of economically imparting effective sealability to a metal surface contact seal section and preventing seizure during fastening is composed by fastening a steel pipe (1) having a male thread (1b) at an end and a non-threaded seal surface (1a) to a coupling (2) having a female thread (2b) in the inner peripheral surface and a non-threaded seal surface (2a). |