| 6659204 |
Method and apparatus for recovering core samples under pressure |
Craig R. Hyland |
2003-12-09 |
| 6378631 |
Apparatus for recovering core samples at in situ conditions |
Craig R. Hyland |
2002-04-30 |
| 6305482 |
Method and apparatus for transferring core sample from core retrieval chamber under pressure for transport |
Craig R. Hyland |
2001-10-23 |
| 6230825 |
Apparatus for recovering core samples under pressure |
Craig R. Hyland |
2001-05-15 |
| 6216804 |
Apparatus for recovering core samples under pressure |
Craig R. Hyland |
2001-04-17 |
| 5253720 |
Method and apparatus for taking an undisturbed core sample |
Steven R. Radford, Haraldur Karlsson |
1993-10-19 |
| 4577704 |
Bearing system for a downhole motor |
— |
1986-03-25 |
| 4573539 |
Hydraulically pulsed indexing system for sleeve-type core barrels |
Jimmy L. Carroll |
1986-03-04 |
| 4512419 |
Coring device with an improved core sleeve and anti-gripping collar |
David S. Rowley |
1985-04-23 |
| 4512423 |
Coring device with an improved weighted core sleeve and anti-gripping collar |
Michael Filshtinsky |
1985-04-23 |
| 4391328 |
Drill string safety valve |
— |
1983-07-05 |
| 4278138 |
Composite heavy metal drill collar |
David S. Rowley, Lothar H. Waldes |
1981-07-14 |
| 4272987 |
Pressure core barrel flushing system |
Harold G. White |
1981-06-16 |
| 4256192 |
Pressure core barrel |
— |
1981-03-17 |
| 4186569 |
Dual spring drill string shock absorber |
— |
1980-02-05 |