Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4618269 | Hardened bearing surface and method of forming same | Robert P. Badrak | 1986-10-21 |
| 4323284 | Thrust face bearing structure for rolling cutter drill bit | John S. Childers | 1982-04-06 |
| 4293167 | Rolling cutter drill bit with improved journal configuration | John D. Parrish | 1981-10-06 |