Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4830123 | Mounting means for cutting elements in drag type rotary drill bit | Percy W. Schumacher | 1989-05-16 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4830123 | Mounting means for cutting elements in drag type rotary drill bit | Percy W. Schumacher | 1989-05-16 |