| Patents for E21B 34 - Valve arrangements for boreholes or wells (14,685) |
|---|
| 09/29/1981 | US4291722 Drill string safety and kill valve |
| 09/29/1981 | CA1109783A1 Control system for subsea well-heads |
| 09/29/1981 | CA1109782A1 Tubing retrievable surface controlled subsurface safety valve |
| 09/29/1981 | CA1109781A1 Flapper valve |
| 09/15/1981 | US4289294 Wellhead flow control devices |
| 09/15/1981 | US4289205 Well safety system method and apparatus |
| 09/15/1981 | US4289201 Well test apparatus |
| 09/15/1981 | US4289165 Equalizing ball valve member |
| 09/08/1981 | US4287954 Subsurface safety valve |
| 09/01/1981 | US4286662 Tubing drain |
| 09/01/1981 | US4286661 Equalizing valve for use in a well tool string |
| 08/18/1981 | US4284152 Pump in core breaker carrier |
| 08/18/1981 | US4284141 Subsurface well apparatus and method |
| 08/04/1981 | US4281715 Bypass valve |
| 07/28/1981 | US4280561 Valve |
| 07/28/1981 | US4280524 Apparatus and method for closing a failed open fluid pressure actuated relief valve |
| 07/21/1981 | US4279272 Flow line monitor pilot valve assembly |
| 07/21/1981 | CA1105352A1 Subsurface safety valve |
| 07/14/1981 | US4278131 Port apparatus for well piping |
| 07/14/1981 | US4278130 Access valve for drill stem testing |
| 07/14/1981 | CA1104922A1 Tubing manipulated test valve and latch assembly |
| 07/07/1981 | US4276937 Well safety system |
| 06/30/1981 | US4275795 Fluid pressure actuated by-pass and relief valve |
| 06/23/1981 | US4274490 Internal fluid control valve for use in oil well remedial operations |
| 06/23/1981 | US4274486 Apparatus for and method of operating a well |
| 06/23/1981 | US4274485 Method and system for well testing |
| 06/23/1981 | US4274484 Dump valve |
| 06/16/1981 | US4273194 Annular flow control safety valve |
| 06/16/1981 | US4273190 Method and apparatus for gravel packing multiple zones |
| 06/16/1981 | US4273186 Well safety valve system |
| 06/09/1981 | US4271903 Retrievable annulus and tubing flow control valves |
| 06/02/1981 | US4270620 Constant bottom contact tool |
| 06/02/1981 | US4270610 Annulus pressure operated closure valve with improved power mandrel |
| 06/02/1981 | US4270606 Apparatus for selective disengagement of a fluid transmission conduit and for control of fluid transmission from a well zone |
| 06/02/1981 | CA1102235A1 Control line exiting coupling |
| 05/27/1981 | EP0029353A2 Apparatus for and method of testing and completing wells |
| 05/19/1981 | US4268283 Fluid control means for geothermal wells |
| 05/12/1981 | US4266614 Valve |
| 05/12/1981 | US4266605 Wireline safety check valve |
| 04/30/1981 | WO1981001181A1 Kelly valving apparatus |
| 04/28/1981 | US4263936 Erosion resistant check valve assembly |
| 04/21/1981 | US4262693 Kelly valve |
| 04/14/1981 | CA1099188A1 Flow line monitor pilot valve assembly |
| 04/08/1981 | EP0026188A1 Apparatus for well logging while drilling |
| 04/07/1981 | US4260021 Plug catcher tool |
| 04/07/1981 | US4260020 Method and tool for controlling fluid flow from a tubing string into a low pressure earth formation |
| 04/07/1981 | US4260017 Cementing collar and method of operation |
| 04/01/1981 | EP0026105A2 A valve for use in well testing and a method of utilising said valve |
| 03/31/1981 | US4259041 High flow standing valve |
| 03/31/1981 | US4258793 Oil well testing string bypass valve |
| 03/31/1981 | US4258786 Safety valve operating apparatus |
| 03/24/1981 | US4257484 Pressure differential circulating valve |
| 03/17/1981 | US4256282 Subsea valve apparatus having hydrate inhibiting injection |
| 03/17/1981 | US4256180 Method of moving a through-the-flowline installed safety valve through a curved flow line |
| 03/17/1981 | US4256179 Indexing tool for use in earth borehole drilling and testing |
| 03/10/1981 | US4254836 Methods and apparatus for controlling fluid flow |
| 03/10/1981 | US4254832 Sampler and measurement apparatus |
| 03/10/1981 | CA1097214A1 Check valve for fluid-producing wells |
| 03/03/1981 | US4253525 Retainer valve system |
| 03/03/1981 | US4253524 High flow check valve apparatus |
| 03/03/1981 | US4253522 Gravel pack tool |
| 03/03/1981 | CA1096953A1 Remote istrumentation apparatus |
| 02/25/1981 | EP0024214A2 A by-pass valve for a well testing apparatus |
| 02/24/1981 | US4252197 Piston actuated well safety valve |
| 02/24/1981 | US4252195 Well test systems and methods |
| 02/24/1981 | US4252188 Actuator |
| 02/24/1981 | US4252143 Actuator |
| 02/17/1981 | US4251191 Method for lifting oil in a well |
| 02/11/1981 | EP0023765A1 Valves, especially for a tubing string |
| 02/10/1981 | US4249611 Marine conductor string provided with a connector and a connector for use in such a marine conductor string |
| 02/10/1981 | US4249599 Well safety system |
| 02/10/1981 | US4249598 Outdoor well depth indicator |
| 02/04/1981 | EP0023399A2 Method and apparatus for testing petroleum wells |
| 02/03/1981 | US4248308 Externally adjusted spring actuated well valve |
| 02/03/1981 | US4248265 Adjustable relief valve |
| 02/03/1981 | CA1094948A1 Self-adjusting liquid spring operating apparatus and method for use in an oil well valve |
| 02/03/1981 | CA1094943A1 Reclosable circulating valve for use in oil well testing |
| 01/28/1981 | EP0023113A1 Actuator for use in a tubing string to operate a foot valve |
| 01/28/1981 | EP0023112A1 Valve, especially for a tubing-string |
| 01/27/1981 | US4246968 Cementing tool with protective sleeve |
| 01/27/1981 | CA1094448A1 Actuator module for wireline cutting safety valve |
| 12/30/1980 | US4241797 Impact tool for dislodging stuck drill bits |
| 12/30/1980 | CA1092483A1 Valve actuator and pilot assembly therefor |
| 12/23/1980 | US4240767 Valving methods and apparatus for flooding and grouting offshore jacket sleeves |
| 12/16/1980 | CA1091578A1 Safety valve for drill stem testing |
| 12/10/1980 | EP0020155A1 Valve with actuator for use in wells |
| 12/09/1980 | US4237980 Check valve for fluid-producing wells |
| 12/02/1980 | CA1090699A1 Vent assembly |
| 11/18/1980 | US4234043 Removable subsea test valve system for deep water |
| 11/11/1980 | CA1089375A1 Bottom-hole gas-liquid separator |
| 10/28/1980 | US4230299 Pressure balanced gate valve having selective actuator systems |
| 10/28/1980 | US4230192 Core sampling apparatus and method |
| 10/28/1980 | US4230187 Methods and apparatus for sensing wellhead pressure |
| 10/28/1980 | US4230185 Rod operated rotary well valve |
| 10/14/1980 | CA1087519A1 Well tools |
| 10/07/1980 | CA1087150A1 Sub-surface gate valve |
| 10/07/1980 | CA1087090A1 Thermostatically controlled valve for automatically regulating the flow of a cooling liquid for gases obtained by underground gasification of solid fuels or by "in situ" combustion of underground hydrocarbons |
| 10/02/1980 | WO1980002051A1 Apparatus for well logging while drilling |
| 09/30/1980 | US4224993 Dewaxing valve for use in oil wells |
| 09/30/1980 | CA1086638A1 Sliding valve |