Issued Patents All Time
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4931612 | Device for forming a closed chamber inside two metal pipes to be connected together by arc welding under a protective gas | Maurice Duhamel | 1990-06-05 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4931612 | Device for forming a closed chamber inside two metal pipes to be connected together by arc welding under a protective gas | Maurice Duhamel | 1990-06-05 |