Abstract: A downhole device, adapted for use in wireline or stickline applications, is provided for incorporation into a downhole string and movement in a wellbore. The device comprises means to orient the device in a well-bore, and one or more conveying means arranged to engage the inner surface of the wellbore and reduce the frictional coefficient. It may also incorporate an eccentric weight and/or a vibrator.

Abstract: Grip and guiding device for directional drilling, in order to drill straight or curved holes with a predetermined path. The device includes a drill string (11-21) comprising parts which rotate during drilling, including a drill bit (11) or a water hammer on its front end and a non-rotating packer unit (14) with a packer tubing (28) comprising one or several projecting pressure pads (25,31-32) arranged behind the drill bit (11) or the water hammer. The pressure pad or pads are arranged to be pressed out towards the drill hole wall by means of the pressure from a drill fluid when this exceeds a certain level. The pressure pad (25) or the pressure pads (25A-25C) may be arranged asymmetrically and/or affects the packer tubing (28) asymmetrically, e.g. by having different heights. The pressure pad(s) force guiding ribs on the opposite side into the hole wall in order to prevent rotation of the packer unit (14). The pressure pad or pressure pads can on deactivation be withdrawn for performing linear drilling.

Abstract: An apparatus for reducing abrasive wear within a housing that includes a body having at least one protrusion selectively positioned and extending outwardly from the outer surface thereof, the body being placed concentrically within the housing and rubbing against the inside surface thereof as the body is moved within the housing. The body is provided with a plurality of slides residing in a like number of grooves formed on the outside surface thereof, each of the slides having a groove formed in at least one side surface thereof The slides are affixed to the body by deforming the material comprising the body into the groove formed in the slide by striking the surface of the material comprising the body adjacent the groove in which the slide resides with enough force to deform the material comprising the body into the groove formed in the side surface of the slide. The apparatus is particularly effective for use with the sucker rod of a pump jack for a subterranean petroleum well.

Abstract: A dual diameter centralizing sub for maintaining stand-off and/or centralizing a tubular member inside a larger diameter tubular member, for instance, in a wellbore. The centralizer is provided with bow springs that compress into grooves between radially outwardly-extending vanes that are spaced around the outer diameter of the sub when compressive force is applied to the bow springs. The vanes extend radially outwardly far enough that the effective diameter of the sub in the area of the vanes is greater than the diameter of the sub and/or the tubing to which it is mounted to provide stand-off even under conditions in which the bow springs are fully compressed.

Abstract: A threaded coupling that has a pair of threaded ends. A number of rigid centralizer ribs are attached or formed on the coupler. Because the coupler has a small length, a special wrench-adapter is used to attach the coupler to the casing string. This adapter fits around the coupler and allows an ordinary wrench to hold the coupler while the casing string is being made up. The coupling also has a gas seal to contain natural gas within the casing without allowing leakage and a torque limiter to ensure that the coupler does not destroy the casing when the casing is rotated in the earth.

Abstract: The present invention provides a down-hole tool guide apparatus 6 suitable for use in controlling movement of a down-hole apparatus 1 provided with a pressurised working fluid supply in a borehole P. The apparatus comprises: a body 7 having a chamber 13 in which is slidably mounted a piston 14. A high pressure end 13a of the chamber 13 is connected 36 to the pressurised working fluid supply 10 for supplying pressurised working fluid to a high pressure side 32 of said piston 14. A low pressure end 13b of the chamber 13 is connected with the outside of the guide apparatus 6 and is provided with a spring 16 for applying a biasing force to the low pressure side 17 of the piston 14 corresponding to a predetermined threshold pressure of the pressurised fluid supply at the high pressure side of the piston 14. The body 7 mounts at least one shoe 25 having an engagement face 26.

Abstract: The present invention relates to a centralizer for use downhole in a well. The centralizer body has one or more contact arms attached to a movable collar. The body is run into the well to a selected depth within the well and the collar is moved to move the contact arms radially outwardly from the body. The collar can be moved sequentially with hydraulic fluid pressure to control the contact arm movement. The contact arm movement can also be locked to retain the centralizer radial force within the well.

Abstract: A subterranean cavity positioning system includes a down-hole device and a cavity positioning device rotatably coupled to a well portion of the down-hole device. The cavity positioning device includes a counterbalance portion operable to automatically rotate the cavity positioning device from a retracted position to an extended position as the cavity positioning device transitions from a well bore into the subterranean cavity. The counterbalance portion is also operable to align the cavity positioning device with the well bore as the down-hole device is withdrawn from the subterranean cavity.

Abstract: A casing centraliser and assembly comprising a tubular and a centraliser, the centraliser comprising a plastics material.

Abstract: A drillable, anti-rotation device for limiting the rotation of a downhole tool, such as a cement plug, when drilling out the down hole tool. The drillable, anti-rotation device comprises a drillable sleeve connected within a non-drillable outer tubular member connected within a pipe string. The sleeve has one or more grooves or other indentations, and/or one or more ribs or other protrusions extending inwardly within the interior of the device for gripping or otherwise retarding the rotation of such downhole tool.

Abstract: A centralizer for guiding a well servicing tool through the bore of a BOP stack or the like and into a radially eccentric position within a wellhead assembly, the centralizer comprising a mandrel having a top end which is connected to a running string and a bottom end to which the well servicing tool is connected, a collar having at least one eccentric hole through which the mandrel extends, the collar being rotatably connected to the mandrel, and an energy absorbing bumper supported above the collar and having at least one opening in alignment with the hole in the collar through which the top end of the mandrel projects; wherein the distance between the center of the collar and the center of the eccentric hole is selected to correspond to the radial distance between the center of the BOP bore and the eccentric position within the wellhead assembly; and wherein the outer diameters of both the collar and the bumper are selected to be only slightly smaller than the diameter of the BOP bore; such that the collar

Abstract: Methods for wellbore operations in an earth wellbore with tubing within casing in an earth wellbore, the wellbore extending down into earth from an earth surface, the tubing including a tubing string with a lower end and extending down within the casing with the lower end at a point above a lower end of the casing, a tubing-casing annulus between the tubing and the casing sealed by a first sealing apparatus, the method including sealing the lower end of the tubing string with a sealing device to prevent fluid flow therethrough, and sealing the tubing casing annulus with a second sealing apparatus above and spaced apart from the first sealing apparatus. In certain aspects the sealing apparatuses provide upper and lower spaced-apart primary barriers. The methods in additional aspects include making an exit opening through the tubing and an exit opening through the casing, each exit opening located between the first sealing apparatus and the second sealing apparatus.

Abstract: A novel multiple configuration hand assembly centralizer system adaptable to virtually all known rock and soil anchoring applications is presented. The primary components to the centralizer include a plurality of straps and two collars which hold the straps in place utilizing a unique locking mechanism. Most preferably the standardized parts will be made from a petroleum based material. The straps are easily and manually inserted into slots in each of the collars. Each collar may be molded to provide slots for three or more straps. The collars are molded with grout passages between slots thereby allowing more than the required amount of grout to be fed through the centralizer. On a multiple configuration centralizer system, a housing assembly and retainer clip are used to frictionally hold the straps at user defined intervals on a standard zip tie.

Abstract: A tie-back insert is installed in a primary wellbore and includes a housing which includes one or more axial bores therethrough and a lateral bore which extends laterally out the side of the housing. The lateral bore allows a liner to pass through the top of the insert, through the lateral bore and into the lateral borehole to a new producing formation. The annulus formed between the housing and the casing is sealed at the upper end of the housing by an upper packer and the lower end of the housing is sealed by stabbing into a lower packer. The upper and lower packers seal around the window cut in the casing. The axial bores allow production fluid from the primary wellbore to be transmitted through the insert to the surface of the well. The insert is placed within the primary wellbore so that the lateral bore is located and oriented adjacent the lateral borehole allowing production fluid from the lateral borehole to transmitted to the surface of the well.

Abstract: A casing centralizer and assembly comprising a tubular and a centralizer, the centralizer comprising a plastics material.

Abstract: A tool is provided for preventing the rotation of a downhole tool or rotary pump stator, the tool comprising a tubular housing and a jaw which is biased radially outwardly from the tool to engage the casing wall for arresting tool rotation and providing significant stabilization of a rotary pump. In doing so, the tool housing moves oppositely to rest against the casing opposite the jaw. The tool housing and the downhole tool are thereby restrained and stabilized by the casing wall. The tool's jaw is released by opposite tool rotation. Preferably, the jaw is biased outwardly from the tool housing to a casing-engaging position by a torsional member, housed along the axis of the hinge of the jaw. The tool is released from the casing by opposite tool rotation which increasingly compresses the jaw toward the housing, twisting the torsional member into torsion, which then acts to urge the jaw outwardly again.

Abstract: A new method and apparatus have been developed which inserts and withdraws tubing from pipes without bending or kinking the tubing. Beneficially, the new method and apparatus may be employed to insert and withdraw tubing to depths greater than ever possible before. The method involves using a thruster pig to provide force to inject the tubing, and skate apparatuses to reduce coiling and friction of the tube. Advantageously, the apparatus is portable, easily handled, and adaptable to handle tubing of differing diameters.

Abstract: Methods are disclosed for wellbore operations in an earth wellbore with tubing within casing in an earth wellbore, the wellbore extending down into earth from an earth surface, the tubing including a tubing string with a lower end and extending down within the casing with the lower end at a point above a lower end of the casing, a tubing-casing annulus between the tubing and the casing sealed by a first sealing apparatus, the method including sealing the lower end of the tubing string with a sealing device to prevent fluid flow therethrough, and sealing the tubing casing annulus with a second sealing apparatus above and spaced apart from the first sealing apparatus. In certain aspects the sealing apparatuses provide upper and lower spaced-apart primary barriers. The methods in additional aspects include making an exit opening through the tubing and an exit opening through the casing, each exit opening located between the first sealing apparatus and the second sealing apparatus.

Abstract: A new method and apparatus have been developed which inserts and withdraws tubing from pipes without bending or kinking the tubing. Beneficially, the new method and apparatus may be employed to insert and withdraw tubing to depths greater than ever possible before. The method involves using skate apparatuses to reduce coiling and friction of the tube. Advantageously, the apparatus is portable, easily handled, and adaptable to handle tubing of differing diameters.

Abstract: A centralised segment (1) comprising a first collar portion (3), a second collar portion (5), and bows (7) extending between the first collar portion (3) and the second collar portion (5). First connectors (9) are provided at first locations of the first collar portion (3) and the second collar portion (5), respectively. Second connectors (11) are provided at second locations of the first collar portion (3) and the second collar portion (5), respectively. The first connectors (9) are engageable with the second connectors (11) of the same or another centraliser segment (1). In this way, one or more centraliser segments (1) are connectable together to form a centraliser around a borehole casing.

Abstract: A centralizer for use in centralizing casing or other tubulars such as tubulars in an oil or gas well comprising an annular body with a bore extending through the body and one or more blades, the centralizer being adapted to fit around a tubular to be centralized, and comprising a tempered metal such as austemperized ductile iron (ADI).

Abstract: Apparatus and method are provided for protecting a reciprocating polish rod from suffering circumferential scoring when it is rotated by a rod-rotator while misaligned and in contact with the carrier bar of a pump jack. A cylindrical sleeve is inserted through the bore of the carrier bar and any additional stacked components supported thereon. An upset at the top of the sleeve retains it within the bore of the carrier bar and any stacked components. The bottom end of the sleeve extends substantially to the bottom of the carrier bar. The polish rod is installed through the bore in the sleeve and can slide and rotate therein. The polish rod is suspended from the carrier structure with a rod clamp. The sleeve guides the polish rod through the carrier structure without permitting accidental contact of the polish rod and the carrier structure and thereby prevents circumferential scoring of the polish rod when the rod is rotated by the rod-rotator.

Abstract: A stand-off device for tubulars comprising a sleeve adapted to fit around a tubular, the sleeve comprising an outer surface and a plurality of blades extending along the outer surface of the sleeve, the blades comprising a bearing surface, wherein the bearing surface of each blade is curved longitudinally. The device may be metallic or non-metallic. Non-metallic devices further comprise a protective coating to inhibit abrasion, corrosion, sparking, and electrolysis. The stand-off device is particularly suitable for use with casing in deviated wellbores.

Abstract: A polymeric centralizer for casing having a body adapted to fit closely about the casing, a plurality of blades extending substantially longitudinally along an outer surface of body, a slit through a blade and opposing groove to allow the centralizer to be spread apart and a fastener to pulling the slit together and tightening the centralizer about the casing. The polymeric centralizer having strength characteristics capable of withstanding the forces encountered in casing operations. The polymeric centralizer is non-sparking for use in hazardous environments, abrasion and wear resistant, and provides protection from electrolysis between adjacent casing strings. The polymeric centralizer is light weight, allowing increased transportation capacity at a economical cost and allows easy attachment to broken down or made-up piping, production string or casing and including hole or cutaways for receiving surface cabling.

Abstract: A downhole tractor is provided that includes a housing and a first wheel assembly coupled to the housing that is operable to translate away from the housing in a first direction. The first wheel assembly has a first electric motor, a first wheel, and a first reduction gear assembly coupled between the first electric motor and the first wheel. A second wheel assembly is coupled to the housing and is operable to translate away from the housing in a second direction that is opposite to the first direction. The second wheel assembly has a second electric motor, a second wheel, and a second reduction gear assembly coupled between the second electric motor and the second wheel. A fluid ram is coupled to the first and second wheel assemblies for selectively translating the first and second wheel assemblies toward and away from the housing. A first controller is provided for controlling the flow of current to the first and second electric motors.

Abstract: The present invention provides an active downhole cutting tool guide device 14 for use in a hole 17 with sides between which a hole-cutting tool 15 mounted on a drill string and provided with said device may be disposed. The guide device 14 comprises at least one elongate longitudinally extending hole-side engagement member 20 mounted on a body 19 disposable, in use of the device, in-line with the drill string, so as to be movable relative to said body 19 between a retracted position and a radially outwardly displaced position for hole-side engagement. Each engagement member 20 has pressurised-fluid operable actuator means 24 formed and arranged for driving said hole-side engagement member 20 between its retracted and hole-aide engagement positions. The guide device 14 includes preasurised fluid supply means 28,18 formmed and arranged for controlling the supply of pressurised fluid to the actuator means 28,18 for operation thereof.

Abstract: Casing accessory equipment especially adapted for restricted diameter applications. The present invention comprises casing accessory equipment, including casing string centralizers, float shoes and float collars, comprising a tubular member having a recessed central section with enlarged diameter end sections. A bow spring centralizer comprising two spaced apart bands connected by a plurality of circumferentially positioned bow spring blades is mounted in the central section. A plurality of lugs are disposed on the recessed central section. Windows in the bands fit over the lugs, restraining rotational and longitudinal movement of the bow spring centralizer within the central recessed section. The bow spring centralizer may collapse to a diameter substantially equal to the diameter of the enlarged end sections, and in the collapsed position retains some longitudinal movement within the central recessed section.

Abstract: A method and apparatus of orienting a tool in a wellbore includes running an orientation string into the wellbore, the orienting string including a positioning device, a measurement device (e.g., a gyroscope), and the tool. The orientation string is positioned in a predetermined interval in the wellbore. The azimuthal orientation of the orientation string is measured with the measurement device. The orientation string is removed from the wellbore, and a tool string is run into the wellbore, the tool string including substantially similar components as the orientation string such that the tool string follows substantially the same path as the orientation string.

Abstract: An electrical cable has helically attached bristles for supporting the electrical cable when pulled through a string of coiled tubing to connect to an electrical submersible pump. The electrical cable and helically attached bristles have a circumscribed diameter greater than the inner diameter of the coiled tubing. The bristles deflect in a direction opposite the direction of pulling the electrical cable so that they grip the wall of the coiled tubing. The bristles apply a resistive frictional force to the wall of the coiled tubing, thereby transferring the weight of the electrical cable to the coiled tubing.