| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of a pipe having a screw thread, which method can significantly reduce the production cost by improving productivity through a mass production and using an inexpensive metal strip. SOLUTION: Ridges or grooves 2a corresponding to threads are formed at least on one face of the metal strip 1 so that the ridges or grooves form a predetermined angle relative to the longitudinal direction of the metal strip. The cylindrical pipe is formed by spirally rolling up, with a predetermined angle, the metal strip 2 having the ridges or grooves 2a.
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