Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5139094 | Directional drilling methods and apparatus | Warren Askew, Alan Martyn Eddison | 1992-08-18 |
| 4947944 | Device for steering a drilling tool and/or drill string | Trevellyn M. Coltman, Alfred Fletcher | 1990-08-14 |