Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7363967 | Downhole tool with navigation system | Kenneth L. Schwendemann, Phillip M. Starr, Michael Linley Fripp, John J. Goiffon, John H. Hales +2 more | 2008-04-29 |
| 7322416 | Methods of servicing a well bore using self-activating downhole tool | Kenneth L. Schwendemann, Phillip M. Starr, Michael Linley Fripp, John J. Goiffon, John H. Hales +2 more | 2008-01-29 |
| 6328118 | Apparatus and methods of separation of materials in an under-balanced drilling operation | Joseph Michael Karigan | 2001-12-11 |
| 6328055 | Annulus pressure referenced circulating valve | — | 2001-12-11 |
| 6148919 | Apparatus having a releasable lock | Neal G. Skinner | 2000-11-21 |
| 6145595 | Annulus pressure referenced circulating valve | — | 2000-11-14 |
| 4753292 | Method of well testing | Paul D. Ringgenberg | 1988-06-28 |
| 4735264 | High pressure gauge carrier | Vincent P. Zeller, Jon B. Christensen, William H. Shoffner | 1988-04-05 |
| 4689744 | Control method for a recording device | Vincent P. Zeller | 1987-08-25 |
| 4655288 | Lost-motion valve actuator | Paul D. Ringgenberg | 1987-04-07 |
| 4618000 | Pump open safety valve and method of use | — | 1986-10-21 |
| 4457377 | Sliding valve float collar | — | 1984-07-03 |