Patents for E21B 31 - Fishing for or freeing objects in boreholes or wells (3,788)
07/1980
07/01/1980CA1080822A1 Well testing downhole tool apparatus and method
05/1980
05/27/1980CA1078368A1 Downhole connector for use with drill string telemetering system
04/1980
04/29/1980US4200158 Fluid retarded accelerating jar with negative and positive pressure chambers
04/08/1980US4196782 Temperature compensated sleeve valve hydraulic jar tool
04/01/1980CA1074697A1 Method and apparatus for recovery of subsea well equipment
03/1980
03/04/1980US4191255 Method and apparatus for cutting and pulling tubular and associated well equipment submerged in a water covered area
02/1980
02/05/1980US4186807 Optional up-blow, down-blow jar tool
02/05/1980CA1071093A1 Methods and apparatus for determining the stuck point of a conduit in a borehole
01/1980
01/29/1980US4185865 Releasable wireline overshot
01/01/1980US4181344 Running tool
01/01/1980US4181196 Method and apparatus for recovery of subsea well equipment
01/01/1980US4181186 Sleeve valve hydraulic jar tool
12/1979
12/18/1979US4179002 Variable hydraulic resistor jarring tool
09/1979
09/11/1979CA1062155A1 Knock-out tool
08/1979
08/14/1979CA1060501A1 Fluid pressure article gripper
07/1979
07/31/1979US4162691 Tubular valve device
07/31/1979CA1059435A2 Annular blowout preventer
07/31/1979CA1059434A1 Well tubing drain
07/17/1979US4161224 Fluid dump mechanism
06/1979
06/12/1979CA1056365A1 Well jar having a time delay section
06/05/1979US4157199 Apparatus for retrieving a tubular member from a well
05/1979
05/01/1979CA1053656A1 Hydraulic jar
03/1979
03/06/1979US4142597 Mechanical detent jars
01/1979
01/23/1979CA1046933A1 Subsurface well apparatus having flexing means and method of using same
12/1978
12/19/1978US4130169 Downhole connector for use with drill string telemetering system
11/1978
11/28/1978US4127297 Releasable overshot
11/14/1978US4125167 Big hole bit
11/07/1978US4124245 Well tool
10/1978
10/31/1978US4123367 Method of reducing drag and rotating torque in the rotary drilling of oil and gas wells
09/1978
09/12/1978US4113038 Drilling jar
09/05/1978US4111271 Hydraulic jarring device
09/05/1978US4111262 Junk boot
08/1978
08/29/1978US4109736 Double acting jar
08/22/1978US4108245 Well cable stop for stripping operations
08/08/1978US4105082 Jarring tool
08/08/1978US4105070 Methods for determining the stuck point of a conduit in a borehole
08/08/1978US4104911 Methods and apparatus for determining the stuck point of a conduit in a borehole
07/1978
07/18/1978US4101157 Tool for fishing an object from a bore hole
07/18/1978US4100968 Technique for running casing
07/11/1978US4099561 Overshot cutter with flexible release cage
07/04/1978US4098338 Jarring method and apparatus for well bore drilling
06/1978
06/06/1978US4093294 Releasable wireline spear
04/1978
04/25/1978US4085808 Self-driving and self-locking device for traversing channels and elongated structures
04/18/1978US4084636 Hydraulic junk retriever
03/1978
03/28/1978US4081043 Hydraulic jars for bore hole drilling
02/1978
02/28/1978US4076086 Fishing jar for accommodation of excess tensile load
01/1978
01/10/1978US4067387 Subsurface well apparatus having flexing means and method of using same
12/1977
12/20/1977US4063603 Drilling fluid lubricant
12/06/1977US4061389 Combination wire line releasable overshot and pull tool
11/1977
11/22/1977US4059167 Hydraulic fishing jar having tandem piston arrangement
11/22/1977US4059164 Self-stabilizing drilling tool
11/22/1977US4059155 Junk basket and method of removing foreign material from a well
10/1977
10/04/1977US4051899 Reset and pulling tool for manipulating well safety valve
09/1977
09/27/1977US4050731 Shifting apparatus
09/13/1977US4047568 Method and apparatus for cutting and retrieving casing from a well bore
08/1977
08/23/1977US4043410 Anti-sticking tool for drill pipe
08/16/1977US4042024 Subsurface well apparatus having flexing means and method of using same
07/1977
07/19/1977US4036312 Well jar
07/12/1977US4035011 Soft set running tool
07/05/1977US4033414 Method and apparatus for releasing a drill string held by differential pressure
07/05/1977US4033413 Wire line well tool and method
06/1977
06/21/1977US4030745 Tool retriever for wells
05/1977
05/17/1977US4023847 Overshot tool
05/17/1977US4023630 Well jar having a time delay section
05/10/1977US4023092 Apparatus for sensing metal in wells
04/1977
04/26/1977US4019574 Subsurface well apparatus having flexing means and method of using same
04/12/1977US4017113 Electrical cable overshot-grappling tool
03/1977
03/15/1977USRE29151 Repulsing clays on drill bits
02/1977
02/15/1977US4007798 Hydraulic jar
02/15/1977US4007790 Back-off apparatus and method for retrieving pipe from wells
01/1977
01/25/1977US4004835 Overshot
01/25/1977US4004643 Mechanical drilling jar
01/11/1977US4002202 Fail-safe safety cut-off valve for a fluid well
10/1976
10/26/1976US3987858 Hydromechanical drilling jar
10/05/1976US3983936 Method of and apparatus for cutting and recovering of submarine surface casing
09/1976
09/21/1976US3981360 Well tubing drain
09/14/1976US3980146 Fishing tool energizer and polymer energy storage element embodied therein
07/1976
07/27/1976US3971543 Tool and kit for electrical fishing
06/1976
06/15/1976US3963081 Double acting mechanical jar
06/01/1976US3960399 Setting and retrieval device for down-hole equipment
05/1976
05/11/1976US3955634 Hydraulic well jar
05/11/1976US3955624 Safety valve for controlling flow in a flow conductor
04/1976
04/13/1976USRE28768 Jarring and bumping tool for use in oilfield drilling strings
04/13/1976US3950021 Pulling and running tool
04/13/1976US3949821 Drill string jarring and bumping tool with piston disconnect
03/1976
03/09/1976US3942833 Running tools
03/09/1976US3942373 Well tool apparatus and method
01/1976
01/06/1976US3930679 Dry hole wire core barrel apparatus
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