Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4645893 | Method for manufacturing spiral-welded steel pipe | Yasumi Shimazaki, Hiroyo Haga, Manabu Hanzawa | 1987-02-24 |
| 4603806 | Method of manufacturing metal pipe with longitudinally differentiated wall thickness | Kazuo Watanabe, Hiromi Seki, Kenji Yamada | 1986-08-05 |
| 4436239 | Method and apparatus for manufacturing spiral pipe | Yasumi Shimazaki, Kazutoshi Kakita, Toshio Hirokawa | 1984-03-13 |