| Patent Number |
Title Of Patent |
Date Issued |
| 4694917 |
Mechanical jarring devices for use in drilling |
September 22, 1987 |
| A jarring device for use in drilling comprises first and second members longitudinally relatively movable between a locked position and a released position said device comprising control means including a pair of locking devices each arranged to prevent relative movement between said mem |
| 4523765 |
High pressure sealing means for longitudinally movable parts of deep-well drilling tools |
June 18, 1985 |
| A high-pressure sealing means for two parts of deep-well drilling tools which are longitudinally movable in relation to one another consists of a wearing sealing ring (7) which is disposed in an annular groove in a first part (1) and bears against the second part (2) and prestressed radi |
| 4511007 |
Locking device for a tool with telescopically displaceable parts |
April 16, 1985 |
| A locking device for a tool with telescopically displaceable parts such as the various tools including a drilling jar used in the deep-well drilling art comprises thickened spindle portion (1) and a sleeve portion (2) with a displaceable sleeve (11) displaceable therein to and away from |
