Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5237793 | Elongated prestressed concrete tank and method of constructing same | — | 1993-08-24 |
| 5129413 | Self washing storage tank | Charles S. Hanskat | 1992-07-14 |
| 4843778 | Elongated prestressed concrete tank and method of constructing same | — | 1989-07-04 |