Issued Patents All Time
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4989752 | Frangible roof joint for storage tanks | John V. Birtwistle, Marvin W. Ringer, Jr. | 1991-02-05 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4989752 | Frangible roof joint for storage tanks | John V. Birtwistle, Marvin W. Ringer, Jr. | 1991-02-05 |