Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5143381 | Pipe joint seal | — | 1992-09-01 |
| 4297780 | Method for connecting sewer pipes to manholes or other pipes | — | 1981-11-03 |
| 4203190 | Method for connecting sewer pipes to manholes | Richard L. Williams | 1980-05-20 |