Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4828294 | Threaded joint for steel pipes containing a sealing device located at the level of the threading | Bernard Plaquin | 1989-05-09 |
| 4828295 | Steel tube threaded joint having an impervious device at the level of the threading | Bernard Plaquin | 1989-05-09 |