Issued Patents All Time
Showing 76–86 of 86 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5314015 | Stage cementer and inflation packer apparatus | Steven G. Streich, John T. Brandell, Lee W. Stepp | 1994-05-24 |
| 5277253 | Hydraulic set casing packer | Alan B. Duell, Anthony M. Badalamenti | 1994-01-11 |
| 5178216 | Wedge lock ring | John T. Brandell | 1993-01-12 |
| 5137087 | Casing cementer with torque-limiting rotating positioning tool | David D. Szarka, Joseph B. Crump | 1992-08-11 |
| 5109925 | Multiple stage inflation packer with secondary opening rupture disc | Lee W. Stepp, Joseph B. Crump, Jerome F. Borges | 1992-05-05 |
| 5038862 | External sleeve cementing tool | John T. Brandell | 1991-08-13 |
| 4880059 | Sliding sleeve casing tool | John T. Brandell | 1989-11-14 |
| 4875524 | Casing centralizer | Billie J. Bradley, Allen T. Joyce | 1989-10-24 |
| 4712619 | Poppet valve | Lee W. Stepp | 1987-12-15 |
| 4315543 | Seal system for wellhead isolation tool diffuser | Thomas J. Luers | 1982-02-16 |
| 4278130 | Access valve for drill stem testing | Robert T. Evans | 1981-07-14 |