Issued Patents All Time
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| RE41759 | Lockable swivel apparatus and method | — | 2010-09-28 |
| RE39509 | Top entry sub arrangement | Charles W. Bleifeld | 2007-03-13 |
| 7131497 | Articulated drillstring entry apparatus and method | Vernon E. Kauffman, Douglas B. Leeth, John Lemke, Max H. Smith | 2006-11-07 |
| 7100699 | High tensile loading top entry sub and method | Vernon E. Kauffman, Billy Dan Jones | 2006-09-05 |
| 6244345 | Lockable swivel apparatus and method | — | 2001-06-12 |
| 5735351 | Top entry apparatus and method for a drilling assembly | — | 1998-04-07 |
| 5284210 | Top entry sub arrangement | Charles W. Bleifeld | 1994-02-08 |