Abstract: A drilling jar in an oil and gas drilling operation or fishing operation includes a control unit having one or more transceivers configured to communicate wirelessly with a surface control unit. The control unit is configured to receive an activation signal from the surface control unit, and cause to activate the drilling jar in response to the activation signal. The wireless transceivers may communicate using any wireless communication technology, including but not limited to Wi-Fi, Wi-Fi Direct, and BLE. A method for operating a drilling jar includes receiving, by a control unit comprising one or more transceivers configured to communicate wirelessly with a surface control unit, an activation signal from the surface control unit, and causing to activate the drilling jar in response to the activation signal.

Abstract: A plug assembly, an anchor tool for a plug, and methods for deploying a plug in a wellbore, of which the anchor tool includes a body, engaging members coupled with the body and configured to expand outward from the body, and a sliding sleeve positioned at least partially around the body. When the sliding sleeve is in a first position, the sliding sleeve covers the engaging members and restrains the engaging members from expanding, and when the sliding sleeve is in a second position, the sliding sleeve uncovers the engaging members and permits the engaging members to expand. The anchor tool also includes a friction-inducing member positioned around the body, and a shearable member coupled with the friction-inducing member and the body. The shearable member restrains the friction-inducing member, causing the friction-inducing member to maintain the sliding sleeve in the first position, until the shearable member is sheared.

Abstract: A spear head assembly includes a spear point having a proximal end and an opposite pointed end. A sleeve has an axial passage and a first end from which the spear point extends, the spear point coupled to the sleeve wherein the spear point can pivot relative to the sleeve and move axially relative to the sleeve. The first end of the sleeve has a smooth continuous abutment surface for the spear point, and the abutment surface forms a funnel like structure which reduces in inner diameter in a direction inward of the sleeve, with the funnel like structure extending between an outer circumferential surface and an inner circumferential surface of the sleeve.

Abstract: In one embodiment, a tubular lifting system for lifting a wellbore tubular includes an outer tubular; an inner tubular disposed in the outer tubular; an annular chamber defined between the inner tubular and the outer tubular; and a tubular piston selectively movable in the annular chamber, wherein the wellbore tubular is connected to the tubular piston and movable thereby.

Abstract: Apparatuses and methods for retrieving a tool or bottom hole assembly. The apparatus may include a latching device that couples to a tool or bottom hole assembly to be retrieved and at least one seal extending radially from the apparatus to engage an inner diameter of a tubular, such as a casing string. A pump inlet is disposed in or through an outer surface of the apparatus uphole of the at least one seal. A pump outlet is disposed in or through an outer surface of the apparatus downhole of the at least one seal. The apparatus may also include a pump for pumping a drilling fluid from the pump inlet to the pump outlet in order to generate a differential pressure across the at least one seal and provide a hydraulic force to effect retrieval of the tool or bottom hole assembly.

Abstract: A retrieval tool may include a body having a first end portion and a second end portion. A protrusion may extend laterally from the body proximate the second end portion of the body. The protrusion may have an engaging surface, two opposing side surfaces, and an outer surface. A path of fluid communication may extend from the first end portion of the body, through the body and the protrusion, to an engaging surface of the protrusion. A method for moving a downhole tool in a wellbore may include running a retrieval tool into a wellbore and pumping fluid to the retrieval tool. The retrieval tool may be engaged with the downhole tool, which may cause a path of fluid communication to experience a change in fluid pressure.

Abstract: A hang-off tool for supporting a tool inside a tubular member includes a logging string configured to generate logging data, a computing system coupled to the logging string and configured to communicate the logging data to another tool, and a radially expandable member having a retracted position and an expanded position. The radially expandable member is configured to engage a radially-increased profile of an inner surface of the tubular member in the expanded position to support the hang-off tool. The radially expandable member is also configured not to engage the radially-increased profile in the retracted position.

Abstract: A method for reverse circulating a tool upwardly through a wellbore, the method including: providing a manipulator tool including an upper end and a lower end, conveying the manipulator tool down hole to a position adjacent a downhole tool, using the manipulator tool to manipulate a the downhole tool, and reversing fluid flow through the well to create a pressure differential about at least one of the manipulator tool and the downhole tool such that the at least one of the manipulator tool and the downhole tool is lifted upwardly through the wellbore. A manipulator tool for use in a reverse circulating method is also described as are a tool catcher, a tool catching assembly and a tool catching method.

Abstract: A device and a method for handling rod-shaped elements on drilling gear are disclosed. The device for handling rod-shaped elements on drilling gear includes a drill rod magazine on which the rod components are deposited between a center of a drill hole and a center of a drilling mast, an elevator with a guide that lifts the drill rods above a drill hole, and a drive for displacing the elevator, a gripper attached to the elevator for picking up the rod component from the drill rod magazine, and a plurality of monitors. The plurality of monitors automatically monitor the movement of the rod-shaped components amongst the magazine, the elevator, and the gripper.

Abstract: A downhole tractor assembly that is configured for open-hole applications. The assembly includes a force monitoring mechanism to help monitor and control forces imparted through a drive mechanism of the tractor in real time. As such, damage to open-hole formations due to excessive tractoring forces may be minimized along with mechanical damage to the tractor. Furthermore, the drive mechanism of the tractor may include multiple sondes and bowsprings with gripping saddles specially configured for contacting the well wall across a large area in a non-point and line manner so as to avoid digging into and damaging the well wall during tractoring.

Abstract: In one embodiment, a tubular lifting system for lifting a wellbore tubular includes an outer tubular; an inner tubular disposed in the outer tubular; an annular chamber defined between the inner tubular and the outer tubular; and a tubular piston selectively movable in the annular chamber, wherein the wellbore tubular is connected to the tubular piston and movable thereby.

Abstract: An overshot (10, 100, 200) for handling equipment (12) defining a spearhead point (14). The overshot (10, 100, 200) includes: a substantially elongated overshot body (16); a pair of lifting dogs (18) pivotally mounted to the overshot body (16) so as to be movable between a dog closed configuration and a dog open configuration; and a dog control element (26) operatively coupled to the lifting dogs (18) for selectively controlling the movement of the lifting dogs (18) between the dog closed and open configurations, the dog control element (26) being operable between an armed configuration, a locked configuration and a released configuration. In the armed configuration, the lifting dogs (18) are movable between the dog closed and open configurations for allowing insertion of the spearhead point (14) therebetween; in the locked configuration, the lifting dogs (18) are locked in the dog closed configuration; and in the released configuration, the lifting dogs (18) are positioned in the dog open configuration.

Abstract: The present invention relates to a pulling tool (1) for latching onto an object (30), such as a plug, downhole in a wellbore The pulling tool comprises a base element (10) extending in a longitudinal direction from a proximal end (10a) for being connected to a wireline tool to a distal end (10b) adapted to engage the object, and a latching mechanism (13) encircling the base element and being movable in the longitudinal direction between a deactivated position and an activated position, comprising a piston sleeve (13), a key element (17) for latching onto the downhole object, the key element being slidably received inside the piston sleeve and extending from an end of the piston sleeve towards the distal end of the base element, and a piston spring forcing (16a) the piston sleeve in the longitudinal direction towards the proximal end of the base element.

Abstract: A grapple device is secured to a mill to allow relative rotation between them. The grapple has an outward bias to allow it to grip the packer bore or an extension from the packer. The mandrel has a wedge adjacent its lower end and torque fingers that fit between grapple segments when relative longitudinal movement occurs between the mandrel and the grapple assembly. The grapple assembly has a left hand thread so that it comes out of the packer if the mandrel engages the grapple assembly in a manner for tandem rotation. The torque fingers on the wedge on the mandrel support the grapple fingers over their length as rotation to the right removes the grapple assembly from the packer bore. Reverse circulation takes away the cuttings into the mill bore where they are separated from the reverse circulating fluid.

Abstract: A hang-off tool for supporting a tool inside a tubular member includes a logging string configured to generate logging data, a computing system coupled to the logging string and configured to communicate the logging data to another tool, and a radially expandable member having a retracted position and an expanded position. The radially expandable member is configured to engage a radially-increased profile of an inner surface of the tubular member in the expanded position to support the hang-off tool. The radially expandable member is also configured not to engage the radially-increased profile in the retracted position.

Abstract: A casing gripper is stabbed into a casing and energized by a top drive, gripping the casing. The casing gripper includes a load bearing mandrel that has external threads. The casing gripper also includes a nut threaded over the external threads, and a wrench having a portion of the upper end of the load bearing mandrel inserted into an opening of the wrench. The wrench is configured to prevent rotation of the nut but allow axial movement while the op drive rotates the mandrel. The casing gripper includes a grapple coupled to the nut and extending along a portion of the lower end of the load bearing mandrel. The grapple moves axially with the nut an is configured to radially expand and engage a casing member.

Abstract: A tubular member handling apparatus is a gripping tool (100) in the form of a body (110) having a longitudinal axis (202) and formed by a plurality of sleeves (750) connected end to end, each sleeve including a frusto-conical bore 752 centered on said longitudinal axis; a clamp member (700) in each sleeve formed by clamp-segments (740), each having side faces (168), end faces (743), a frusto-conical exterior surface (741) adapted to match said frusto-conical bore, and a cylindrical interior surface (745); cage-segments (220) connected to said interior surface and having a plurality of windows (222) partially closing recesses (214) in said interior surface, which recesses are elongate in said longitudinal direction, house a roller (230) and have a base (236) inclined in said longitudinal direction so that, at a lower end (232) of each recess the roller protrudes through said window and at an upper end (234) thereof the roller protrudes less or not at all; a bias mechanism 780, urging said clamp-segments apart

Abstract: A grapple for controlling, monitoring and stopping the flow of oil, natural gas and the like from a broken, flanged pipe. A housing encloses a ring of material that is more ductile than the broken pipe flange. The force applied by a weight, presses a driving device against the broken pipe flange periphery, the force so applied distorts the ductile ring, thereby establishing a fluid-tight seal between the flange and the housing.

Abstract: A grapple for use in an overshot has a tension ring with a reduced helix diameter but the helix diameter is not reduced on either sides of the control finger slot. One embodiment includes expansion blades on the inner diameter (“ID”) of the tension ring to allow the grapple to expand substantially before the fish reaches the segments. An embodiment provides for a control with an offset finger to allow the guide thread ID to be smaller than the bowl helix major ID. Also provided is grapple control for a spiral grapple that has at least one gap to allow the grapple control to be more compliant during fishing operations. The control may include one or more bridges of reduced thickness. Alternate embodiments include gaps and support bands with or without bridges and/or a backup ring to help eliminate misalignment of the grapple control with the support shoulder of the overshot guide.

Abstract: An overshot has an articulated seal that can be set against the fish when the fish is engaged by the tool. The seal can be actuated from swelling due to exposure to well fluid or mechanically or hydraulically from the string that supports it. The use of spears or overshots with the articulated seal feature is contemplated. If a swelling design is used it can respond to water or hydrocarbons that are found at the subterranean location.

Abstract: A release assembly (200) for releasing a portion of a tool string in a wellbore. The release assembly (200) includes an outer housing (202) having a fishing receptacle (206) disposed therein. The fishing receptacle (206) includes a fishing neck (208). A support assembly (214) is disposed within the housing (202). The support assembly (214) has a first position wherein the support assembly (214) engages the fishing neck (208) to prevent separation of the fishing receptacle (206) from the housing (202) and a second position wherein the support assembly (214) is disengaged from the fishing neck (208) no longer preventing separation of the fishing receptacle (206) from the housing (202). An actuator (224), disposed within the housing (202), maintains the support assembly (214) in the first position until actuation thereof allows the support assembly (214) to shift to the second position.

Abstract: A method of sealing a well comprising introducing a plug axially into the well, with a mouth of the plug turned up and a bottom wall part turned down, the plug being positioned in the well at a desired depth, after which the plug is inflated by injecting a high-pressure liquid into it via its mouth so that a tubular wall part of the plug expands radially beyond its elastic limit and presses firmly and tightly against the wall of the well by a crimping effect, while its bottom wall part serves as a sealing partition, forming a tight barrier between lower and upper parts of the well that it separates, the plug having an internal axial mandrel that connects its mouth to its bottom wall, the mandrel being pierced with channels that allow injection of high-pressure liquid inside the plug via the mouth and channels.

Abstract: A completion assembly of a top packer and zone isolation packers separated by screens has a disconnect in a selected zone to be fractured or gravel packed that is armed before such a procedure starts. Initially when the assembly of the outer completion and the inner string are properly located and all the screens valved off, all the packers are pressure set and the packer set release device associated with each packer is armed. Before starting a fracturing or gravel packing operation from a given zone isolation packer, a disconnect for that zone packer is armed so that if the inner string sticks in that packer, the inner string is sheared and removed and another trip is used to grab the top packer and pick up. Such picking up releases all the packers down to the one armed disconnect. The disconnect releases bringing up the remnant of the inner string stuck in the packer just above the actuated disconnect.

Abstract: A fishing tool is provided to enable retrieval of fish from a mineral extraction system. The fishing tool includes a frustoconical member, an outer tubular member, and an inner tubular member. The inner tubular member includes a plurality of receptacles configured to receive a plurality of jaws. Each of the jaws may include teeth on an inward facing surface of the jaw. The outer tubular member may be hydraulically actuated to cause the jaws to move radially inward and engage the fish, enabling removal of the tool and the fish. Systems and methods that include the fishing tool are also provided.

Abstract: A hydraulically powered fishing tool is provided for retrieving another tool or tubular stuck in a well. A tool housing is supported in a well on a work string, and the housing encloses a plurality of pistons (16, 28, 34) each movable in response to pressurized fluid transmitted through the work string. An anchor (52) axially fixes the position of the tool in the well, and a tool mandrel (40) is axially movable relative to tool housing when the anchor is set. A fishing device (82) engages the another tool or tubular, so that axial movement of the mandrel in response to the plurality of pistons dislodges the stuck tool or tubular.

Abstract: A retrievable stimulation frac (retrievable stimulation frac) plug for a well casing having an elongate mandrel having a fluid flow bore, a check valve mandrel seal moveable between an open position and a closed position for selectively sealing the fluid flow bore, a sealing mechanism for sealing between the mandrel and the casing, and a locking mechanism for axially locking the retrievable stimulation frac plug in the casing.

Abstract: A tubular retrieval method comprises applying a cyclically varying fluid pressure to the interior of a section of cut bore-lining tubular (20). The tubular may be casing which it is desired to remove from a bore. A pulling force may also be applied to the tubular.

Abstract: The present invention relates to a tool for installation of units in connection with oil wells, comprising a housing (1) with an attachment device (12) for attachment to a well installation, a telescopic device (30, 31, 32) for extension of the tool, a torsional force transmission device (13) for rotation of an internal movable element (2) of the tool. According to the invention the internal movable element (2) comprises a pressure face (21), which in an operative condition is exposed to a well pressure and a counter-pressure face (22), with a sealing arrangement (26) between the housing (1) and the internal movable element (2) provided between these pressure faces (21, 22) and devices (23) which are arranged in such a manner that a pressure can be applied to the counter-pressure face.

Abstract: The retrieving tool engages an equalizing sleeve on a jar down movement while the packer or bridge plug release sleeve is held fixed with a locking dog. The initial jarring down allows the tool to engage the equalizing sleeve and pull it up subsequent to the initial engagement by jarring down. Pulling or jarring up then opens the equalizing ports while still holding the release sleeve locked using a trapped collet. A subsequent jarring down allows engagement of a second sleeve so that a subsequent pulling or jarring up moves the second sleeve away from the collet that had otherwise held the set position of the packer or bridge plug. A pull or jar force up brings up the now released packer or bridge plug.

Abstract: A well fishing method and system is described. In at least one example of the invention, a method of retrieval of material (e.g., a tubing string) having broken control or monitoring lines from a cased well is provided. The method comprises: isolating, from the well casing, broken lines above the material to be retrieved, thereby creating a substantially axial work passage; grasping the material to be removed through the substantially axial work passage; and pulling the material to be retrieved and the restrained lines from the well. Example shrouds, probes and other members are also described.

Abstract: A jarring device includes an outer housing which defines an axial flow path therethrough. An impact rotator is retained within the housing and is rotatable therewithin between a first rotational position and a second rotational position to create a jarring impact. A torsional spring biases the impact rotator toward the first rotational position. Fluid flow through the housing rotates the impact rotator from the first to the second rotational position.

Abstract: A cobble and small boulder debris removal device including a quiescently open 3 prong claw, and a series of springs and cables within or affixed to a shaft to close the prongs in gripping and holding such cobbles when encountered in the pre-clearance of a borehole, to be then removed by being lifted away and released via a relaxation of a lever connected with a main actuating cable.

Abstract: A fishing tool includes a grapple and an exciter in vibration transmissive communication with the grapple and method.

Abstract: A method and apparatus for a debris barrier assembly having a sleeve, an outer housing assembly coupled to the sleeve, and first and second biasing members disposed within the outer housing assembly. A support member is coupled to the sleeve and is in contact with an end of the first and second biasing members. The debris barrier assembly is coupled to a polished bore receptacle to prevent debris from entering the PBR. The debris barrier assembly is operable to compensate for a pressure differential between the internal region of the PBR and the external region of the surrounding wellbore. The debris barrier assembly and the PBR may be run in the wellbore on a work string, and the sleeve may be actuated to actuate a downhole tool connected to the sleeve to perform a downhole operation. The debris barrier assembly may be retrieved from the wellbore using the work string.

Abstract: A staging tool arrangement for gas well production assistance, comprising an elongated staging tool having an elongated upper portion and an elongated lower portion. The upper portion has a sliding relationship with the lower portion thereof. A displaceable annular seal is arranged about the lower portion. A displaceable enclosure is arranged on the elongated lower portion so as to slidably expose and to slidably enclose the annular seal.

Abstract: A rope socket comprises a slip cone subassembly having a straight outer diameter and a tapered inner diameter. A plurality of slips is positioned within the slip cone body. A retainer ring holds the slips together. A guide plug is positioned within the slips to maintain the slips in an opening position during insertion of a cable. A spring stabilizer having a spring thereon is coupled above the slip cone assembly to ensure even compression of the spring. A safety slot is located on the body of the rope socket in order to provide a visual indication of the cable position.

Abstract: A shifting tool is run on slickline and has an on board power supply. Rotary motion of the motor is converted to linear motion of the shifting tool using a ball screw device. The grip is obtained with longitudinal motion of a grip linkage and an on board jar then can do the shifting. Alternatively a linear motor can be used to extend and retract the grip assembly and shift using the jar tool. Optionally the tool can be anchored and linear motion from the on board power source operating a motor can do the shifting.

Abstract: A method of installing a drilling tool at a lower end of a string of casing suspended in a borehole employs a setting tool run by wireline. The setting tool is latched to a drilling tool connected a drill lock assembly. After landing in a profile sub at the lower end of the casing, fluid pressure is applied to the interior of the string of casing to actuate the setting tool. The setting tool moves to latch the drill lock assembly to the sub so that torque may be transmitted between the profile sub and the drill lock assembly. The setting tool movement also releases the setting tool from the drill lock assembly for retrieval.

Abstract: A method of raising a tubular, comprising attaching a lifter to a tubular associated with a wellbore, and operating the lifter to transmit a downward force to a subterranean formation via a surface of the wellbore formed in the subterranean formation while also operating the lifter to transmit an upward force to the tubular. A lifter for lifting a tubular associated with a wellbore comprising a securing mechanism configured to restrict movement of the securing mechanism relative to an upper tubular portion, and a piston configured to be received within a lower tubular portion and configured to promote a seal between the piston and the lower tubular portion.

Abstract: Coiled tubing spears for retrieving a section of cut coiled tubing comprises a mandrel having attachment members, e.g., spears, at upper and lower ends for facilitating connection of the upper end of the mandrel to a spooled section of coiled tubing and the lower end of the mandrel to a section of cut coiled tubing disposed in a wellbore. Coiled tubing spears comprise one or more centralizers that are releasably secured to the mandrel. The centralizer(s) facilitate lining up a lower attachment member, or spear, with the bore of the section of cut coiled tubing so that the mandrel can be secured to the cut coiled tubing for retrieval. During retrieval of the cut coiled tubing, the centralizer(s) are released from the mandrel so that the mandrel and attachment members can continue through an injector head.

Abstract: An overshot tool is provided for interconnecting and sealing between a lower tubular (C) in a well and an upper tubular (30). A tubular expander sleeve (36) and an overshot sleeve (26) are supported in a well on an upper tubular. The tool housing (60) encloses a plurality of axially stacked pistons (58, 68, 74), which generate an axial force to move the expander sleeve downward and radially expand a portion of a lower tubular to seal between an outer diameter of the lower tubular and an inner diameter of the overshot sleeve.

Abstract: A hydraulic overshot apparatus designed to slide over plain end tubing and set by applying hydraulic fluid, under pressure, via a hydraulic setting port, into a center chamber which allows pressure to direct to two different piston areas. The setting piston compresses packer elements and tubing slips against the outer diameter (O.D.) of the tubing. The test piston compresses tubing test elements against the inner diameter (I.D.) of the tubing. The setting pressure is ported through the upper setting and test portion to allow pressure to move from the center chamber to the lower outer portion. The lower outer portion includes a body lock ring and a setting piston for setting the packer elements. Setting pressure moves the setting piston down through the body lock ring. As the setting piston moves down, it ratchets down through the body lock ring.

Abstract: A completion assembly of a top packer and zone isolation packers separated by screens has a disconnect in a selected zone to be fractured or gravel packed that is armed before such a procedure starts. Initially when the assembly of the outer completion and the inner string are properly located and all the screens valved off, all the packers are pressure set and the packer set release device associated with each packer is armed. Before starting a fracturing or gravel packing operation from a given zone isolation packer, a disconnect for that zone packer is armed so that if the inner string sticks in that packer, the inner string is sheared and removed and another trip is used to grab the top packer and pick up. Such picking up releases all the packers down to the one armed disconnect. The disconnect releases bringing up the remnant of the inner string stuck in the packer just above the actuated disconnect.

Abstract: A grapple for use in an overshot has a tension ring with a reduced helix diameter. However, the helix diameter is not reduced on either sides of the control finger slot to allow the grapple to remain in contact with the control. In the alternative, a composite helix member may be utilized. Another embodiment comprises the inclusion of expansion blades on the inner diameter (“ID”) of the tension ring which allow the grapple to expand substantially before the fish reaches the segments. Another embodiment provides for a control with an offset finger to allow the guide thread ID to be smaller than the bowl helix major ID. Yet another embodiment provides a spiral grapple having grooves along its axis to provide the ability to catch a larger range of fish.

Abstract: A latching mechanism for selectively disengaging an upper pump from a motor in an ESP. The latching mechanism comprises barbs formed on an upper end of an upper shaft that are engaged by a tool to lift the upper shaft until a lower end of the upper shaft disengages from an upper end of a motor shaft. When the upper pump is disengaged from the motor shaft, only a lower pump is driven by the motor and flow of well fluid is circulated past the disengaged upper pump via a bypass line. The upper pump shaft may reengage the motor shaft if additional lift is required.

Abstract: A hydraulically powered fishing tool is provided for retrieving another tool or tubular stuck in a well. A tool housing is supported in a well on a work string, and the housing encloses a plurality of pistons (16, 28, 34) each movable in response to pressurized fluid transmitted through the work string. An anchor (52) axially fixes the position of the tool in the well, and a tool mandrel (40) is axially movable relative to tool housing when the anchor is set. A fishing device (82) engages the another tool or tubular, so that axial movement of the mandrel in response to the plurality of pistons dislodges the stuck tool or tubular.

Abstract: A downhole tool is provided that includes a grip assembly for contacting a well formation. The grip assembly includes a gripper body; and a centralizer that is attached to and radially expandable with respect to the gripper body and that has a geometry which is lockable by a locking device. The grip assembly also includes a force amplifier in force transmitting relation with the centralizer, wherein the force amplifier transfers a force in a first direction to a much larger force in a second direction when the centralizer is locked by the locking device.

Abstract: A casing-while-drilling bottom hole assembly is releasably connected with a casing string. A retrieval tool is run into the casing string and latched to the bottom hole assembly. Slips are mounted to the retrieval tool, the slips being retracted during running in. Differential pressure moves the retrieval tool and bottom hole assembly upward, and the slips engage the casing string to prevent downward movement if the pressure differential drops too low. A flow passage extends through the retrieval tool and the bottom hole assembly. A check valve in the retrieval tool allows downward flow through the flow passage but prevents upward flow, so that fluid may be circulated through the retrieval tool and bottom hole assembly while suspended with the slips.

Abstract: A well tool for applying a pulling or a pushing force to an object in an interior of a well bore comprising: a) an inner member comprising a first elongated member, a second elongated member and an actuation means axially interconnecting the first elongated member and the second elongated member; b) an outer elongated member longitudinally moveably engaged with the inner member; c) a first seal defined between the first elongated member and the outer elongated member; d) a second seal defined between the second elongated member and the outer elongated member; e) a first piston area defined at a first end portion of the outer elongated member between an outer diameter of the outer elongated member and a sealed outer diameter of the first elongated member; f) a second piston area defined at a second end portion of the outer elongated member between the outer diameter of the outer elongated member and a sealed outer diameter of the second elongated member; and g) a sealed chamber defined between the first seal a

Abstract: An extension sub for a downhole fishing tool, the extension sub comprising a tubular having a threaded pin end and a threaded box end, the tubular having an interior wall defining a bore, and cutting elements fixed to the interior wall of the tubular and extending into the bore of the tubular. Such a device may be referred to as a string shoe.