| Patents for E21B 4 - Drives for drilling, used in the borehole (6,032) |
|---|
| 06/29/1976 | US3966369 Inlet and outlet ports and sealing means for a fluid driven motor |
| 06/29/1976 | US3965995 Machine for boring a large diameter blind hole |
| 06/22/1976 | US3964558 Fluid actuated downhole drilling device |
| 06/22/1976 | US3964555 Apparatus for obtaining earth cores |
| 06/22/1976 | US3964551 Pneumatic impact drilling tool |
| 06/15/1976 | US3963228 Drill string shock absorber |
| 05/25/1976 | US3958645 Bore hole air hammer |
| 05/11/1976 | US3955631 Soil sampler |
| 04/27/1976 | US3952819 Fatigue resistant anvil bit for percussion rock drill |
| 04/27/1976 | US3952816 Drilling system and method of pulling it up |
| 04/27/1976 | US3952813 Percussive device for driving holes in soil |
| 04/20/1976 | US3951219 Drill tool comprising a core barrel and a removable central portion |
| 04/06/1976 | US3948588 Swivel for core drilling |
| 04/06/1976 | US3948058 Device for soil sampling under water |
| 03/30/1976 | US3946819 Well tool and method of use therefor |
| 03/23/1976 | US3945445 Boring apparatus provided with drill bits freely rotatable around their own axis |
| 03/23/1976 | US3945444 Split bit casing drill |
| 03/16/1976 | US3944303 Thrust support for a fluid motor used in drilling wells |
| 03/16/1976 | US3944003 Bore hole air hammer |
| 03/09/1976 | US3942595 Self-propelled percussive machine for boring holes |
| 03/02/1976 | US3941423 Method of and apparatus for extracting oil from oil shale |
| 03/02/1976 | US3941196 Percussive air hammer and core bit apparatus |
| 02/17/1976 | US3938598 Belling apparatus |
| 02/17/1976 | US3938596 Turbo-drill |
| 02/03/1976 | US3936247 Floating flow restrictors for fluid motors |
| 02/03/1976 | US3935910 Method and apparatus for moulding protective tubing simultaneously with bore hole drilling |
| 01/27/1976 | US3934662 Core bit |
| 01/27/1976 | US3934660 Flexpower deep well drill |
| 01/20/1976 | US3933210 Drill head assembly |
| 01/20/1976 | US3933209 Drilling apparatus and technique using down-hole motor |
| 01/06/1976 | US3930749 Turbodrill |
| 01/06/1976 | US3930545 Tiltable coupling |