Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4875530 | Automatic drilling system | Tommy S. Frink, Dwayne V. Cochran, Will L. McNair | 1989-10-24 |
| 4836300 | Method of performing drilling operations from a derrick | — | 1989-06-06 |
| 4796863 | Dual cluster crown block | — | 1989-01-10 |