| Patents for E21B 34 - Valve arrangements for boreholes or wells (14,685) |
|---|
| 03/25/1992 | CN2099836U Oil well digital-controlled production distribution valve |
| 03/24/1992 | CA1297786C Sub surface safety valve block, particularly suitable for the risers of offshore platforms |
| 03/17/1992 | US5095994 Flow actuated safety valve with retrievable choke and metal seals |
| 03/17/1992 | US5095808 Sequential remote control plug release system |
| 03/17/1992 | CA1297400C Hydraulic lock alleviation device for a well cementing stage tool, such a tool and a method of alleviating an hydraulic lock |
| 03/11/1992 | CN2098549U Blow-out device of eccentric mouth of oil well |
| 03/11/1992 | CN1015811B Subsurface safety valve block, particularly suitable for risers of off shore platform |
| 03/11/1992 | CN1015809B Core plugging notifying mechanism of rope core drilling tool |
| 03/10/1992 | US5094294 Well pump assembly and packer |
| 03/10/1992 | CA1296997C Subsurface well safety valve |
| 03/04/1992 | CN1015727B Combined multifunctional oil wellhead assembly |
| 03/03/1992 | US5092406 Apparatus for controlling well cementing operation |
| 03/03/1992 | US5092359 Handle enclosure for valves |
| 02/25/1992 | US5090481 Fluid flow control apparatus, shifting tool and method for oil and gas wells |
| 02/18/1992 | CA1295983C Ball valve |
| 02/13/1992 | DE4027414C1 Tubular rock bore drill stem - has concentric channels for fluids and has spring-loaded control valves |
| 02/12/1992 | EP0470160A1 Well control apparatus. |
| 02/12/1992 | CN2095934U Slurry pump screw valve for petroleum drill |
| 02/11/1992 | US5086808 Balanced sleeve control choke |
| 02/11/1992 | US5086802 Safety check valve |
| 02/04/1992 | US5085277 Sub-sea well injection system |
| 01/28/1992 | US5083582 Valve with removable insert |
| 01/28/1992 | CA2040013A1 Blowout preventer |
| 01/22/1992 | EP0467573A2 Subsurface pressure actuated well apparatus |
| 01/21/1992 | US5082062 Horizontal inflatable tool |
| 01/21/1992 | US5081909 Releasable latch mechanism for attaching an actuator to a valve |
| 01/15/1992 | EP0466472A2 Annulus pressure responsive downhole testing tool |
| 01/15/1992 | EP0465543A1 Method and apparatus for monitoring well fluid parameters. |
| 01/15/1992 | EP0465503A1 Drill stem test tools. |
| 01/14/1992 | CA1294214C Apparatus for retaining axial movement relative to a cylindrical housing |
| 01/11/1992 | CA2046698A1 Hydraulic system for electronically controlled pressure activated downhole testing tool |
| 01/10/1992 | CA2046470A1 Method and apparatus for actuating a downhole tool |
| 12/26/1991 | WO1991019883A1 Tools for wells |
| 12/24/1991 | US5074717 Clamped body replacement tool |
| 12/24/1991 | US5074519 Fail-close hydraulically actuated control choke |
| 12/24/1991 | US5074518 Proportional annular B.O.P. controller |
| 12/11/1991 | EP0460902A2 Drill pipe bridge plug and method of use |
| 12/10/1991 | US5070950 Remote controlled actuation device |
| 12/10/1991 | US5070944 Down hole electrically operated safety valve |
| 12/10/1991 | US5070902 Lateral orifice water regulator |
| 12/10/1991 | US5070595 Method for manufacturing electrIc surface controlled subsurface valve system |
| 12/07/1991 | WO1991019073A1 Soil displacement hammer with reversing mechanism |
| 12/07/1991 | CA2084650A1 Soil displacement hammer with reversing mechanism |
| 12/04/1991 | CN1056729A Oil field deep-well pump ceramic valve |
| 11/21/1991 | EP0457653A1 Safety sleeve and device for wells, particularly for a subterranean reservoir of fluid under pressure |
| 11/20/1991 | CN2089067U Check valve for drill pipe |
| 11/13/1991 | EP0456415A2 Control apparatus and method responsive to a changing stimulus |
| 11/13/1991 | EP0456397A1 Sequential remote control plug release system for wells |
| 11/12/1991 | CA2042256A1 Safety sleeve for a borehole communicating with an underground reserve of fluid under pressure, and associated safety system, and an associated borehole operating method |
| 11/12/1991 | CA1291923C Hydraulic power system |
| 11/06/1991 | EP0454947A1 Boring ram |
| 11/05/1991 | US5062480 Self actuated intake valve assembly for insert subsurface reciprocating pumps |
| 10/30/1991 | EP0454465A2 External sleeve downhole cementing tool |
| 10/30/1991 | CN1014537B Drill stem test method and apparatus |
| 10/22/1991 | US5058684 Drill pipe bridge plug |
| 10/22/1991 | US5058682 Equalizing means for a subsurface well safety valve |
| 10/22/1991 | US5058667 Reciprocating water well pump |
| 10/22/1991 | CA1291026C Safety valve for oil well, and tool for mounting said valve |
| 10/19/1991 | CA2038649A1 Catalytic downhole reactor and steam generator |
| 10/16/1991 | EP0452033A2 A fluid flow control system, assembly and method for oil and gas wells |
| 10/16/1991 | CN1014335B Drilling tool for core-taking with rope |
| 10/15/1991 | US5056600 Control apparatus and method responsive to a changing stimulus |
| 10/15/1991 | US5056599 Method for treatment of wells |
| 10/13/1991 | CA2037791A1 Fluid flow control system, assembly and method for oil and gas wells |
| 10/08/1991 | US5054558 Equalizing blank valve apparatus and methods |
| 10/08/1991 | US5054510 Selective valve to pass fluids |
| 10/08/1991 | CA1290242C Polished rod stuffing box with safety valve for a beam pumped production well |
| 10/01/1991 | US5052482 Catalytic downhole reactor and steam generator |
| 10/01/1991 | CA1289869C Well head with adjustable flow for the exploitation of biogas |
| 09/25/1991 | EP0447707A1 Valve with removable insert |
| 09/24/1991 | US5050839 Valve |
| 09/24/1991 | US5050681 Hydraulic system for electronically controlled pressure activated downhole testing tool |
| 09/24/1991 | CA2037696A1 Valve with removable insert |
| 09/24/1991 | CA1289464C Perforate, test and sample tool and method of use |
| 09/19/1991 | WO1991014076A1 Well clearing and cleaning device |
| 09/17/1991 | US5048611 Pressure operated circulation valve |
| 09/17/1991 | US5048604 Sucker rod actuated intake valve assembly for insert subsurface reciprocating pumps |
| 09/10/1991 | CA1288685C Cement control valve device or sub |
| 09/03/1991 | US5044602 Blowout preventer |
| 09/03/1991 | US5044444 Method and apparatus for chemical treatment of subterranean well bores |
| 09/03/1991 | US5044443 Method and apparatus for producing wells |
| 09/03/1991 | US5044441 Pack-off well apparatus and method |
| 08/27/1991 | US5042584 Injecting liquids |
| 08/20/1991 | US5040621 Flushing means for drilling tools |
| 08/20/1991 | US5040606 Annulus safety valve |
| 08/20/1991 | US5040603 Sequential remote control plug release system |
| 08/20/1991 | CA1287848C Equipment for rod string, namely a drill string, having a coupling with a side light for insertion of a cable |
| 08/14/1991 | CN2082758U Single-flow production sharing device of oil producing pipe column |
| 08/13/1991 | US5038862 External sleeve cementing tool |
| 08/13/1991 | CA1287567C Circulation valve and method for operating the same |
| 08/13/1991 | CA1287566C Injection mandrel |
| 08/08/1991 | WO1991011736A1 Apparatus for inductively coupling signals between a downhole sensor and the surface |
| 07/30/1991 | US5035292 Whipstock starter mill with pressure drop tattletale |
| 07/30/1991 | US5035258 Valve with removable insert |
| 07/30/1991 | CA1286998C Modular wireline tool connector with swivel coupling |
| 07/09/1991 | US5029646 Orifice well safety valve with release mechanism |
| 07/09/1991 | US5029643 Drill pipe bridge plug |
| 07/09/1991 | CA1285863C Foot valve for pumping wells |
| 07/03/1991 | EP0435856A2 Multi-mode testing tool |
| 07/03/1991 | CN2080098U Anti-freezing device for air discharg pipe of wellhead casing |