| Patents for E21B 4 - Drives for drilling, used in the borehole (6,032) |
|---|
| 03/07/1991 | WO1991002880A1 Drill |
| 03/05/1991 | US4997292 Vertical bearing assembly |
| 02/28/1991 | DE3927952A1 Drilling for blasting - uses cradle and washing nozzle together with carriage mounted drive and hydraulic hammer |
| 02/28/1991 | DE3927625A1 Deep well diamond boring head - with high-speed central drill bit and slow-speed outer drill bit driven by moineau motor |
| 02/26/1991 | CA1280797C Diamond bearing and manufacture thereof |
| 02/12/1991 | US4991669 Device for controlling the passage of a flushing medium in impact machines |
| 01/17/1991 | DE3919719A1 Hydrostatic rotary drive for deep boring - has hydraulic motor and removable hydraulic supply line in casing string |
| 01/09/1991 | EP0406411A1 Down-hole mud actuated hammer. |
| 01/08/1991 | US4982801 Flexible coupling for downhole motor |
| 01/01/1991 | US4981181 Ram boring machine for laying service lines without excavation |
| 12/27/1990 | WO1991000410A1 Device for guiding a drilling tool into a well and for exerting thereon a hydraulic force |
| 12/13/1990 | DE3918799A1 Core drilling in rock and ice - uses hydraulic breaker flat jacks as side cutters to enlarge boreholes and to remove debris |
| 12/12/1990 | EP0193618B1 Apparatus and method for assembling and matching the working components of a sectional screw downhole motor |
| 12/11/1990 | US4976655 Connecting rod assembly for downhole drilling |
| 12/11/1990 | CA1277696C Bearing sleeves |
| 12/06/1990 | DE3917688A1 Drainage pipe advance system for dug wells - uses drilling rods, with drilling head and retainer jaws for pipe |
| 12/05/1990 | EP0400921A2 Drill bit assembly with concentric rotatable cutting elements and method of drilling |
| 12/04/1990 | US4974687 For driving holes in the ground |
| 11/28/1990 | CN2066480U Wet type sealing inverse circulation pneumatic down-hole hammer |
| 11/20/1990 | US4971162 Continuous drill feed apparatus |
| 11/15/1990 | DE3915538A1 Rotary hard-rock drill - has eccentrically-mounted hammer in housing with milling teeth on bottom edge |
| 11/14/1990 | EP0397627A1 Tunnel boring machine |
| 11/14/1990 | CN1010421B Reversible underground piercing device |
| 11/14/1990 | CN1010420B Gang drill construction |
| 11/13/1990 | US4969528 Method and apparatus for continuous pilot hole coring |
| 10/31/1990 | EP0395167A1 Device and method for making a borehole in the ground |
| 10/31/1990 | EP0394567A1 Steerable drilling mole |
| 10/23/1990 | US4964477 Pneumatic percussive device |
| 10/23/1990 | US4964474 Flexible tunneling apparatus and method |
| 10/18/1990 | WO1990012164A1 Device for making holes in the ground |
| 10/17/1990 | EP0392544A2 Drilling tool |
| 10/17/1990 | EP0392237A2 Self-propelled boring ram |
| 10/17/1990 | EP0392013A1 Bearing unit for vertical support |
| 10/16/1990 | US4962818 Downhole motor with an enlarged connecting rod housing |
| 10/13/1990 | CA2014570A1 Drilling tool with retractable pilot drilling unit |
| 10/11/1990 | DE3911469A1 Drilling installation |
| 10/10/1990 | EP0391161A2 Automatic ram drill device |
| 10/04/1990 | DE3910266A1 Direct electric bit drives |
| 10/03/1990 | CN1009849B Percussing device for percussion revolution drill |
| 10/03/1990 | CN1009848B Down hole drill improvement |
| 10/03/1990 | CN1009847B Air pressure impact drilling method and apparatus for same |
| 10/02/1990 | CA1274818A1 Device for simultaneously boring a well and inserting a casing string |
| 10/02/1990 | CA1274817A1 Steering and control system for percussion boring tools |
| 09/26/1990 | EP0388627A1 Drop-hammer |
| 09/25/1990 | US4958692 Downhole stabilizers |
| 09/25/1990 | US4958691 Fluid operated vibratory jar with rotating bit |
| 09/25/1990 | US4958690 Drilling device with hydraulic percussion generator for earth drilling purposes |
| 09/25/1990 | US4958689 Method of providing a high pressure surge of working fluid to an underground percussive mole |
| 09/18/1990 | US4957175 Soil drilling equipment |
| 09/12/1990 | EP0387218A1 Device in impact machines |
| 09/12/1990 | EP0387217A1 Device in impact machines |
| 09/11/1990 | US4955439 Self-propelled subsoil penetrating tool system |
| 09/05/1990 | EP0385959A2 Percussion drill |
| 09/05/1990 | CN1009469B Borehole drill construction |
| 09/04/1990 | US4953626 Ram boring machine having a pull-and-turn reversing gear |
| 09/04/1990 | CA1273624A1 Device for submerged drilling of foundations |
| 09/02/1990 | CA2011265A1 Percussion drill |
| 08/23/1990 | DE3905106A1 Deep-hole hammer drill with water-flushing arrangement |
| 08/22/1990 | EP0383737A1 Drill bit |
| 08/13/1990 | CA2009861A1 Drill bit |
| 08/08/1990 | EP0380909A2 Method and coring apparatus for subterranean rock drilling |
| 08/01/1990 | EP0379584A1 Instrument for percussion-rotary drilling |
| 08/01/1990 | CA2008975A1 Method and apparatus for directional coring |
| 07/26/1990 | WO1990008004A1 Down-hole mud actuated hammer |
| 07/11/1990 | EP0266386B1 Improvements in drilling using downhole drilling tools |
| 07/11/1990 | CN2059178U Earth hole maker |
| 07/10/1990 | US4940097 Fluid powered rotary percussion drill with formation disintegration inserts |
| 07/04/1990 | EP0376585A2 Downhole surge valve for earth boring apparatus |
| 07/03/1990 | US4938297 Ram boring machine |
| 06/30/1990 | CA2005522A1 Downhole surge valve for earth boring apparatus |
| 06/26/1990 | US4936397 Earth drilling apparatus with control valve |
| 06/13/1990 | EP0372225A2 Boring ram |
| 06/12/1990 | US4932483 Down hole hammer |
| 06/12/1990 | US4932482 Downhole motor with an enlarged connecting rod housing |
| 05/29/1990 | US4928775 Downhole surge valve for earth boring apparatus |
| 05/29/1990 | US4928770 Mechanical manipulation tool with hydraulic hammer |
| 05/22/1990 | US4926949 Thermal shield for drilling motors |
| 05/17/1990 | WO1990005235A1 Directional drilling apparatus and method |
| 05/15/1990 | US4924948 Shock absorbing bit retaining ring |
| 05/08/1990 | US4923018 Percussion drill |
| 05/03/1990 | WO1990004726A1 Bearing unit for vertical support |
| 05/02/1990 | EP0365612A1 Drill. |
| 05/01/1990 | US4921056 Hammer drills for making boreholes |
| 05/01/1990 | US4921052 Downhole recirculating hammer |
| 04/18/1990 | EP0363424A1 Apparatus for working in pipes |
| 04/17/1990 | US4917194 Improved downhole hammer |
| 04/11/1990 | EP0362481A2 Boring ram |
| 04/05/1990 | WO1990003488A1 Improvements in pneumatic percussion hammers |
| 04/03/1990 | US4913243 Percussion drill and method of controlling same |
| 03/28/1990 | CN1040845A Percussion-rotary drilling tool |
| 03/27/1990 | US4911250 For rock drilling |
| 03/22/1990 | WO1990002864A1 A borehole, as well as a method and an apparatus for forming it |
| 03/20/1990 | US4909337 Rotor of a screw hydraulic downhole motor, method for its production and a device for its production |
| 03/07/1990 | EP0357317A1 Electric motor |
| 03/07/1990 | EP0356666A2 Boring ram for laying service lines without excavation |
| 03/06/1990 | US4905775 Drilling system and flow control apparatus for downhole drilling motors |
| 03/06/1990 | US4905773 Self-propelled subsoil penetrating tool system |
| 02/27/1990 | CA1266208A1 Valveless pneumatic hammer |
| 02/21/1990 | CN2053264U Hydrodynamic mono-screw pump |
| 02/20/1990 | EP0327575A4 A pneumatic percussion hammer. |