Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4869319 | Wellhead structure | Edward J. Szymozak, Thomas G. Cassity, William M. Taylor, Peer H. Tiemer, Larry M. Hoes +1 more | 1989-09-26 |
| 4828293 | Wellhead slip and seal assembly | Delbert Edwin Vanderford | 1989-05-09 |
| 4825945 | Wellhead valve | — | 1989-05-02 |