Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5746279 | Method and apparatus for changing bits while drilling with a flexible shaft | Kenneth L. Havlinek, Thomas D. MacDougall, Alan J. Sallwasser, Duane LaDue, Wayne A. Tyler +4 more | 1998-05-05 |
| 5692565 | Apparatus and method for sampling an earth formation through a cased borehole | Thomas D. MacDougall, Andrew Kurkjian, Aaron Flores, Duane LaDue | 1997-12-02 |
| 5687806 | Method and apparatus for drilling with a flexible shaft while using hydraulic assistance | Alan J. Sallwasser, Kenneth L. Havlinek, Thomas D. MacDougall, Duane LaDue, Wayne A. Tyler +4 more | 1997-11-18 |