Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4887629 | Plug valve and method of assembly | John V. Ballun | 1989-12-19 |
| 4863144 | Plug valve | John V. Ballun | 1989-09-05 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4887629 | Plug valve and method of assembly | John V. Ballun | 1989-12-19 |
| 4863144 | Plug valve | John V. Ballun | 1989-09-05 |