| Patents for E21B 34 - Valve arrangements for boreholes or wells (14,685) |
|---|
| 05/30/1989 | US4834177 Unidirectional filter for hydraulic systems |
| 05/30/1989 | US4834176 Well valve |
| 05/23/1989 | US4832126 Diverter system and blowout preventer |
| 05/23/1989 | CA1254504A1 Well cementing apparatus |
| 05/16/1989 | US4830107 Well test tool |
| 05/16/1989 | CA1254130A1 Pump open safety valve |
| 05/09/1989 | US4828025 Blowout control means |
| 05/09/1989 | US4828024 Diverter system and blowout preventer |
| 05/02/1989 | US4825953 Well servicing system |
| 05/02/1989 | US4825945 Wellhead valve |
| 05/02/1989 | US4825895 Water injection choke valve |
| 04/25/1989 | US4823880 Gaswell dehydrate valve |
| 04/25/1989 | US4823877 Open hole pipe recovery circulation valve |
| 04/18/1989 | US4823125 Method and apparatus for stabilizing a communication sensor in a borehole |
| 04/18/1989 | US4821817 Actuator for an appliance associated with a ducted body, especially a drill rod |
| 04/11/1989 | CA1252382A1 Method of well testing |
| 04/04/1989 | US4817723 Apparatus for retaining axial mandrel movement relative to a cylindrical housing |
| 04/04/1989 | US4817718 Hydraulically activated firing head for well perforating guns |
| 03/28/1989 | US4815546 Top head drive assembly with axially movable quill |
| 03/21/1989 | US4813493 Hydraulic top drive for wells |
| 03/21/1989 | US4813481 Expendable flapper valve |
| 03/21/1989 | CA1251391A1 Valve for oil or gas well |
| 03/15/1989 | EP0307266A1 Method and apparatus for driving specialised intervention equipment into a borehole with at least one section strongly inclined relative to the vertical |
| 03/15/1989 | EP0161261B1 Cylindrical gate valve apparatus and method |
| 03/14/1989 | US4811652 Constant differential overpressure device |
| 03/07/1989 | US4809733 Fail-safe gate valve with separated actuators |
| 02/28/1989 | US4807700 Wireline downhole annulus valve |
| 02/28/1989 | US4807699 Tubing sleeve |
| 02/23/1989 | WO1989001584A1 Apparatus for maintenance of ball valve |
| 02/14/1989 | US4804045 Oil and gas well diversionary spool assembly |
| 02/14/1989 | US4804044 Perforating gun firing tool and method of operation |
| 02/14/1989 | CA1249966A1 Retrievable landing method and assembly for a well bore |
| 02/07/1989 | US4802359 Tool for measuring pressure in an oil well |
| 02/07/1989 | CA1249772A1 Drill stem testing system |
| 02/01/1989 | EP0301734A2 Downhole circulation valve |
| 01/31/1989 | US4800958 Annulus pressure operated vent assembly |
| 01/31/1989 | CA1249509A1 Submerged valve control apparatus |
| 01/25/1989 | EP0300627A1 Method and apparatus for stabilizing a communication sensor in a borehole |
| 01/19/1989 | DE3723044A1 Safety valve |
| 01/17/1989 | US4798247 Solenoid operated safety valve and submersible pump system |
| 01/17/1989 | CA1248936A1 Device for the remote actuation of an appliance associated with a duct in which an incompressible fluid circulates, particularly a device for actuating a stabilizer of a set of drill rods |
| 01/10/1989 | US4796708 Electrically actuated safety valve for a subterranean well |
| 01/10/1989 | US4796705 Subsurface well safety valve |
| 01/10/1989 | US4796704 Drop ball sub-assembly for a down-hole device |
| 01/10/1989 | US4796699 Well tool control system and method |
| 01/10/1989 | CA1248441A1 Pressure operated test valve |
| 01/05/1989 | DE3720573A1 Tool which can be releasably inserted in a borehole casing string |
| 01/03/1989 | US4794989 Well completion method and apparatus |
| 01/03/1989 | US4794957 Bending strain relief for hose bundle |
| 12/28/1988 | EP0296268A1 Single acting hydraulic actuator with variable return force |
| 12/28/1988 | EP0296207A1 Method and device for taking measurements and/or carrying out interventions in a well subjected to a hydraulic compression. |
| 12/28/1988 | CA1247519A Production tube and its connection, facilitating the completion of an oil well |
| 12/27/1988 | US4793417 Apparatus and methods for cleaning well perforations |
| 12/21/1988 | EP0295922A2 Downhole tool and method for perforating and sampling |
| 12/21/1988 | EP0295734A2 Polished rod stuffing box with safety valve for a beam pumped production well |
| 12/20/1988 | US4791991 Subsurface well safety valve with hydraulic strainer |
| 12/20/1988 | US4791990 Liquid removal method system and apparatus for hydrocarbon producing |
| 12/20/1988 | US4791856 Single acting hydraulic actuator with variable return force |
| 12/20/1988 | CA1246988A1 Method and apparatus for gravel packing a well |
| 12/20/1988 | CA1246987A2 Multi-mode testing tool and method of testing |
| 12/13/1988 | US4790378 Well testing apparatus |
| 12/06/1988 | US4789032 Orienting and circulating sub |
| 11/30/1988 | CN88210331U Circulating valve under oil well exploited by thermodynamic method of pouring vapor |
| 11/29/1988 | US4787446 Inflatable packer and fluid flow control apparatus for wellbore operations |
| 11/29/1988 | CA1245742A1 Well production controller system |
| 11/29/1988 | CA1245548A1 Tubing drain valve useful with heavy, sand-bearing oil |
| 11/17/1988 | WO1988008917A1 Blowout preventer |
| 11/17/1988 | WO1988008069A3 Apparatus for use in drilling |
| 11/17/1988 | EP0290560A1 Shut down valve for use in a subwater position. |
| 11/17/1988 | EP0233209B1 Drop ball sub-assembly for a down-hole device |
| 11/15/1988 | US4784225 Well valve assembly method and apparatus |
| 11/08/1988 | US4782897 Multiple indexing J-slot for model E SRO valve |
| 11/08/1988 | US4782896 Retrievable fluid flow control nozzle system for wells |
| 11/08/1988 | US4782895 Pumped oil well bottom safety valve |
| 11/08/1988 | CA1244342A1 Stage cementing apparatus |
| 11/01/1988 | US4781607 Electrical connector assembly |
| 11/01/1988 | CA1243942A1 Surface controlled subsurface safety valve |
| 10/26/1988 | EP0288239A2 Perforating gun firing tool |
| 10/26/1988 | EP0288238A2 Method and apparatus for perforating well bores |
| 10/25/1988 | CA1243599A1 Well apparatus |
| 10/20/1988 | WO1988008069A2 Apparatus for use in drilling |
| 10/12/1988 | EP0286302A2 Top head drive assembly with axially movable quill |
| 10/11/1988 | US4776401 Foot valve for pumping wells |
| 10/11/1988 | US4776400 Oil-well flap-type safety valve |
| 10/11/1988 | US4776399 Oil-well safety-valve and tool for installing the same |
| 10/11/1988 | US4776395 Well bore treating fluid tool |
| 10/11/1988 | CA1242969A1 Injection control device for subterranean well conduit |
| 10/04/1988 | US4774980 Piloted wellhead flow control valve |
| 09/27/1988 | USRE32755 Accelerated downhole pressure testing |
| 09/27/1988 | CA1242472A1 Annular seal with v-cut |
| 09/20/1988 | US4771982 Slidable electric valve device having a spring |
| 09/20/1988 | US4771831 For use in a well tubing in a well casing |
| 09/20/1988 | US4771633 Cell for testing the sealing quality of an oil-well safety-valve, a testing process and valve for use therein |
| 09/14/1988 | EP0203172B1 Non-return valve for bore hole sleeves |
| 09/14/1988 | CN87213600U Arbitrary moving oil jet under well |
| 09/13/1988 | US4770389 For use with subsea production trees |
| 09/13/1988 | US4770243 Device for regulating the rate of flow of water which is separated from its mixture with hydrocarbons and reinjected into the bottom of the well |
| 09/06/1988 | US4768594 Valves |
| 09/06/1988 | US4768539 Pipeline safety valve |
| 08/30/1988 | US4766960 Standing and injection valve |