Issued Patents All Time
Showing 1–17 of 17 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11976542 | Frac distribution tower | Rex E. Duhn | 2024-05-07 |
| 8863829 | Wellhead isolation tool and wellhead assembly incorporating the same | Rex E. Duhn | 2014-10-21 |
| 8333237 | Wellhead isolation tool and wellhead assembly incorporating the same | Rex E. Duhn | 2012-12-18 |
| 8272433 | Wellhead isolation tool and wellhead assembly incorporating the same | Rex E. Duhn | 2012-09-25 |
| 7726393 | Wellhead isolation tool and wellhead assembly incorporating the same | Rex E. Duhn | 2010-06-01 |
| 7520322 | Wellhead isolation tool and method of fracturing a well | Rex E. Duhn | 2009-04-21 |
| 7493944 | Wellhead isolation tool and method of fracturing a well | Rex E. Duhn | 2009-02-24 |
| 7416020 | Wellhead isolation tool, wellhead assembly incorporating the same, and method of fracturing a well | Rex E. Duhn | 2008-08-26 |
| D573484 | Steam releasing package | — | 2008-07-22 |
| 7322407 | Wellhead isolation tool and method of fracturing a well | Rex E. Duhn | 2008-01-29 |
| 6920925 | Wellhead isolation tool | Rex E. Duhn | 2005-07-26 |
| 6588510 | Coil tubing hanger system | Gary Andrew Card | 2003-07-08 |
| 6543533 | Well tubing rotator | Rex E. Duhn | 2003-04-08 |
| 5908134 | Tubular above ground gas storage vessel | George Carl Hale, Charles Michael Coldren | 1999-06-01 |
| 5429268 | Tubular above ground gas storage vessel | George Carl Hale, Charles Michael Coldren | 1995-07-04 |
| 4687018 | Jacketed valve | Duane M. Eagen | 1987-08-18 |
| 4469122 | Modular check valve | — | 1984-09-04 |