Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4858707 | Convex shaped diamond cutting elements | George Fyfe | 1989-08-22 |
| 4846290 | Underreamer with revolving diamond cutter elements | — | 1989-07-11 |
| 4813500 | Expendable diamond drag bit | — | 1989-03-21 |