Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4842816 | High toughness steel | Akihiro Miyasaka, Takeshi Terasawa | 1989-06-27 |
| 4804021 | Highly tough ERW steel pipe with distinguished sour resistance | Yasushi Hasegawa | 1989-02-14 |
| 4802270 | Apparatus for passing optical fibers through tubular products | Kunio Kashiwaya, Nobuo Saeki, Youichi Yabuki, Kuniyuki Ozoe, Shinichi Fukushima +1 more | 1989-02-07 |