Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4884633 | A hydraulic remotely-controlled bleeder valve for a well head | Denis Devilleger, Philippe Majewski | 1989-12-05 |
| 4848401 | Isolation chamber valve | Denis Devilleger | 1989-07-18 |