Patents
Sitemap › E21 - Earth or rock drilling; Mining › E21B - Earth or rock drilling; Obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells › E21B 21 - Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
Patents for E21B 21 - Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor (13,780)
02/1991
02/05/1991US4989673 Lost circulation fluid for oil field drilling operations
02/05/1991US4989522 Separation, combustion using plasma arc
01/1991
01/30/1991CN2070354U Washing liquid-saving petroleum pipe end
01/30/1991CN1011430B Process for avoiding the equipment of well-drilling to block up in the well
01/23/1991CN1048738A Lost circulation fluid for oil field drilling operations
01/22/1991US4986122 Fluid velocity measurement instrument
01/15/1991US4984641 Swivels
01/01/1991US4981182 Sealed rotary blast hole drill bit utilizing air pressure for seal protection
01/01/1991US4981037 Method for determining pore pressure and horizontal effective stress from overburden and effective vertical stresses
12/1990
12/27/1990EP0403538A1 Process for treatment of drilling mud
12/26/1990CN1048076A Method of managing prodn. well
12/25/1990US4979577 Flow pulsing apparatus and method for down-hole drilling equipment
12/25/1990US4979562 Float equipment including float collars and modular plugs for well operations
12/19/1990EP0403437A2 Oil based drilling fluids
12/19/1990EP0403025A2 Method of drilling and lining a borehole
12/19/1990CN2067748U Long pipe water closing type pumping recycle back device for residue extraction
12/18/1990US4977967 Steering and lubricating apparatus for portable earth boring machine with steering head
12/13/1990WO1990015220A1 Rock drilling bit
12/12/1990EP0402337A2 Drill tool
12/09/1990CA2018445A1 Drill tool
12/05/1990EP0400137A1 Dual wall well development tool
12/04/1990US4974690 Adapter for drilling strings with controllable air passage
12/04/1990US4974672 Gravel packing system for a production radial tube
11/1990
11/20/1990US4971157 Apparatus for the removal of spoil when making trenches of great depth
11/14/1990CN1010422B Drill pipes and castings utilizing mult-conduit tubulars
11/13/1990US4969513 High pressure automatic kelly valve
11/06/1990US4967841 Horizontal well circulation tool
11/06/1990CA1275959C Method and apparatus for treating oil-water-solids sludges and refinery waste streams
11/06/1990CA1275793C Carboxymethyl guar based drilling fluids
10/1990
10/30/1990CA1275714C Method and apparatus for determining fluid circulation conditions in well drilling operations
10/23/1990US4964918 Grouting composition
10/23/1990US4964465 Method employing liquidized sand for controlling lost circulation of drilling fluids
10/23/1990CA1275525C Polymeric viscosifier for water-immiscible liquids
10/18/1990WO1990012193A1 Coupling for drilling machine with dust extractor
10/17/1990CN1046176A Water-wettable drilling mud additives containing uintaite
10/16/1990US4962819 Mud saver valve with replaceable inner sleeve
10/11/1990DE3911159A1 Coupling for drill pipe with force transmission
10/10/1990EP0391874A2 Flushing means for drilling tools
10/06/1990CA2062316A1 Eccentric drilling tool
10/03/1990CN1009847B Air pressure impact drilling method and apparatus for same
10/02/1990US4960740 Adducts of smectite clay with phosphoglycerides, such as soybean lecithin; oil well working fluids
09/1990
09/27/1990DE4007907A1 Lenkvorrichtung fuer eine bohrerspitze in einem bohrloch Steering device for a drill tip in a borehole
09/25/1990US4958685 Method for plugging lost circulation areas and lost circulation material to be used therefor
09/20/1990DE3909058A1 Dry-drilling extraction system
09/19/1990CN2062378U Gas-removing and sand-removing device
09/18/1990US4957187 Gear-driven lubricant circulation system
09/18/1990US4957166 Lost circulation treatment for oil field drilling operations
09/13/1990CA2011972A1 Device for steering a drill bit
09/12/1990EP0387218A1 Device in impact machines
09/12/1990EP0387217A1 Device in impact machines
09/12/1990EP0386810A2 Method for improving a drilling process by characterizing the hydraulics of the drilling system
09/11/1990US4956104 Organophilic polymers
09/11/1990US4955949 Mud saver valve with increased flow check valve
09/07/1990WO1990010138A1 Well forming process
09/05/1990CN1009469B Borehole drill construction
09/04/1990US4953622 Subterranean well casing float tool
09/04/1990US4953595 Mud pulse valve and method of valving in a mud flow for sharper rise and fall times, faster data pulse rates, and longer lifetime of the mud pulse valve
09/04/1990CA1273624A1 Device for submerged drilling of foundations
08/1990
08/31/1990CA2009114A1 Process and apparatus for recovering reusable water from waste drilling fluid
08/29/1990EP0384792A2 Method and apparatus for measuring the coefficients of adhesion and viscosity of a drilling fluid
08/29/1990EP0384378A1 Method and installation for the continuous disposal and processing of water-based, fluid and solid drilling residues
08/28/1990US4951760 Remote control actuation device
08/27/1990CA2010943A1 Method for improving a drilling process by characterizing the hydraulics of the drilling system
08/25/1990WO1990010043A1 Water-wettable drilling mud additives containing uintaite
08/25/1990CA2046879A1 Water-wettable drilling mud additives containing uintaite
08/23/1990WO1990009507A1 Oil removal from hydrocarbon contaminated cuttings
08/23/1990DE3905106A1 Deep-hole hammer drill with water-flushing arrangement
08/22/1990EP0383737A1 Drill bit
08/21/1990US4949575 For investigating properties of subsurface formations
08/14/1990US4948925 Apparatus and method for rotationally orienting a fluid conducting conduit
08/13/1990CA2009861A1 Drill bit
08/09/1990CA2009606A1 Drilling fluid adhesion and friction coefficients measuring apparatus and cell
07/1990
07/31/1990US4944347 Method and apparatus for direct high velocity preparation of completion/workover systems
07/24/1990US4942929 Disposal and reclamation of drilling wastes
07/18/1990EP0378045A1 Hydraulic drill hammer
07/17/1990US4941951 Method for improving a drilling process by characterizing the hydraulics of the drilling system
07/12/1990DE3900453A1 Drill head of a horizontal heading machine
07/11/1990EP0266386B1 Improvements in drilling using downhole drilling tools
06/1990
06/28/1990WO1990007048A1 Dual wall well development tool
06/28/1990WO1990006981A1 Use of selected diester oils as drilling fluids, in particular for exploiting off-shore petroleum or natural gas deposits (ii)
06/28/1990WO1990006980A1 Use of selected ester oils in bore-flushing fluids, particularly for the development of offshore oil and gas fields (i)
06/27/1990EP0374672A1 Use of selected fatty esters in drilling fluids, especially in offshore oil or gas recovery
06/27/1990EP0374671A1 Use of selected ester oils in drilling fluids, especially for off-shore oil or gas recovery
06/26/1990US4936397 Earth drilling apparatus with control valve
06/26/1990CA1270810A1 Method of drilling a borehole
06/21/1990DE3841871A1 Method for drilling holes in masonry or concrete
06/20/1990EP0373695A1 Monitoring drilling mud
06/19/1990US4934466 Device for borehole hydraulic mining
06/15/1990CA2005195A1 Monitoring drilling mud
06/14/1990WO1990004699A3 Float collar and plug for use in wells
06/14/1990CA2005605A1 Dual wall well development tool
06/05/1990US4930586 Hydraulic drilling apparatus and method
05/1990
05/30/1990EP0370709A1 Flow pulsing apparatus for drill string
05/22/1990US4926949 Thermal shield for drilling motors
05/16/1990EP0368563A2 Drilling fluid additives
05/16/1990CN1007990B Polymeric compositions and methods of using them
05/15/1990US4925344 Method and apparatus for replacing buried pipe
05/15/1990US4924950 Method of drilling a well by utilizing AE/MA measurement
05/15/1990US4924949 Drill pipes and casings utilizing multi-conduit tubulars
05/15/1990US4924942 Using thixotropic preflush fluid of water, cement, calcium sulfate and hardener
1 ... 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 ... 138