Issued Patents 2002
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6412579 | Two stage drill bit | — | 2002-07-02 |
| 6401845 | Cutting element with stress reduction | — | 2002-06-11 |
| 6340064 | Bi-center bit adapted to drill casing shoe | Rogerio H. Silva | 2002-01-22 |