Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4340344 | Apparatus for manufacture of thermoplastics pipe | Derek Walker | 1982-07-20 |
| 4323535 | Manufacture of thermoplastics pipe | Derek Walker | 1982-04-06 |
| 4318681 | Manufacture of thermoplastics pipe | Derek Walker | 1982-03-09 |