Abstract: An apparatus and method are disclosed that allow for downhole expansion of long strings of rounded tubulars, using a technique that expands the tubular from the top to the bottom. The apparatus supports the tubular to be expanded by a set of protruding dogs which can be retracted if an emergency release is required. A conically shaped wedge is driven into the top of the tubing to be expanded. After some initial expansion, a seal behind the wedge contacts the expanded portion of the tube. Further driving of the wedge into the tube ultimately brings in a series of back-up seals which enter the expanded tube and are disengaged from the driving mandrel at that point. Further applied pressure now makes use of a piston of enlarged cross-sectional area to continue the further expansion of the tubular. When the wedge has fully stroked through the tubular, it has by then expanded the tubular to an inside diameter larger than the protruding dogs which formerly supported it.

Abstract: Downhole apparatus is disclosed for use in expanding liner or tubing. The apparatus comprises a body for connection to a string and an expansion portion on the body. The expansion portion includes a plurality of radially movable parts for defining an outer surface thereof. The parts are initially arranged in an axially and circumferentially offset first configuration in which the parts may assume a smaller diameter first configuration. The apparatus is then run Into a borehole and through a length of expandable tubing. The parts are the moved radially outwardly and axially aligned such that the parts assume a larger diameter second configuration and define a substantially continuous outer circumference. The expansion portion is then pulled through the tubing to expand the tubing.

Abstract: A method and a device for replacing a seal element in an undersea blowout preventer is provided. A complete system includes a control center on the surface, an umbilical from the control center to a remotely operated vehicle (ROV), and a seal element carrier manipulated by the ROV. The carrier includes either retrieving tool or a running tool, which retains a cartridge which is to be inserted into or has been retrieved from a BOP. The cartridge is split along a vertical plane, with each half of the cartridge becoming a temporarily integral part of a pipe ram on either side of the BOP. Alignment ramps on the cartridge mate with complementary surfaces on the respective faces of the pipe rams.

Abstract: A stroke indicator has been invented for indicating that a movable inner member of an hydraulically activated wellbore tool or apparatus has moved, particularly that movement of such a member indicating that a stroke of the tool or apparatus has occurred. In one aspect such an indicator is used to indicate that the stroke of a wellbore tubular patch expander system has been completed. A tubular patch has been invented which includes two or more connected tubular patch members. A tubular patch system has been invented for patching operations which, in one aspect, is useful as a "through tubing" tubular patch system and has a body and a series of selectively expandable members which, once having passed through a tubular of a first diameter, are expandable in a tubular of a second diameter larger than the first diameter and then operable to expand a liner patch to seal a leak in the tubular of the second diameter.

Abstract: A system designed to patch single and multiple casing leaks that occur in an injection well annulus where there is direct communication from the outermost casing string to the original open-hole wellbore and the adjacent earth strata. This system utilizes a four-stage process which consists of four separate types of fluids. The first injection stage is a CaCl.sub.2 solution in water. The second injection stage utilizes H.sub.2 SiO.sub.3, Na.sub.2 in a solution of water to create sodium metasilicate Na.sub.2 SiO.sub.3 in water. These two react in a double replacement chemical reaction to yield an aqueous phase and a solid phase. The third injection stage is then implemented, the same including a bentonite/attapulgite/diatomaceous earth slurry with large plugging materials suspended therein. The fourth stage utilizes covalently bonded N.sub.2 in a gaseous state. After injection of the first three stages N.sub.

Abstract: A damage-resistant filter for use in subterranean wells has at least one layer of a filter medium, such as a sintered supported porous membrane, coaxially disposed about a perforated support member. The filter may also include a drainage layer disposed between the inner support member and the filter medium, and a protective covering, such as a perforated cage, surrounding the filter medium. The filter is particularly suitable for removal of sand and other particulates from fluids produced in a well.

Abstract: A gas diverter tool is disclosed for use in improving the operation of an oil and gas well that has cracks, holes or leaks in the casing. The tool includes a thick walled tubular body for in-line threaded connection within a tubing string below a packer carried by the tubing string. The thick wall of the tubular body includes four circumferentially spaced passageways extending longitudinally therethrough to provide gas inlet openings. The upper ends of the passageways are removably closed, and the lower ends are diametrically reduced to provide valve seats. Spherical check valves are loosely received within the passageways above to seat downwardly against the valve seats. Elongated wiper rods are loosely slidable in the passageways and downwardly abut against the ball valves to hold the check valves closes.

Abstract: An apparatus for sealing non-regular holes in a perforation in a wall, including a sealing member configured to be forcibly pressed into an inner surface of the perforation, an expandable member for forcing the sealing member against the inner surface of the perforation, and an expander member for causing the expandable member to force the sealing member against the inner surface of the perforation.

Abstract: An apparatus and method for sealing an inner wall of a portion of a casing positioned in a well employs an inflatable sleeve having an outer surface and a conformable composite sleeve of curable composition extending around the outer surface of the inflatable sleeve. The inflatable sleeve is inflated to compress the composite sleeve against the surface of the inner casing wall. A local, activatable energy source, positioned downhole to deliver heat to the composite sleeve, is activated to cure the composite sleeve to form a hardened sleeve. The hardened sleeve presses against the inner wall of the casing portion to create a fluid seal. The embodiments shown have a number of preferred features. The local energy source includes an exothermic heat energy source for generating heat energy to cure the composite sleeve. The composite sleeve includes a mixture of resin and a curing agent, and the exothermic heat source includes thermite. The thermite includes a composition having a metal oxide and a reductant.

Abstract: A casing patch is disclosed which uses one or more fins which elastically flex to accept a casing stub. The casing stub is prepared with a dressing tool containing a special mill to obtain the requisite finish on its outer surface prior to insertion of the casing patch. The flexible fin or fins provide a metal-to-metal seal to the outer surface of the casing patch and a grip assembly holds the joint together. In certain applications, the fins can be combined with a resilient seal where the fins preferably provide a complete extrusion barrier to the resilient seals. Using the fins which preferably are integral to the body, alone or in combination with a resilient seal or seals, the wall thickness of the joint can be maintained at thicker values for a given size as compared to prior designs, thus, ensuring a sufficient pressure rating for the joint which is at least equal to the rating of the casing stub.

Abstract: The present invention relates to a method for casing a well (1) from a tubular preform (2) lowered into a well in folded state. The preform comprises seal means (3, 4) at both ends so that it can be inflated in order to take on a second, unfolded state in which the preform is polymerized.Means (30) for disconnecting lower seal means (3) in order to take the latter up to the surface in a receptacle (11) are inserted into the casing.The invention also relates to a casing device comprising disconnecting means (30) and a receptacle (11) for the lower seal means (3).FIG. 1 to be published.

Abstract: A tubular patch system has been invented for patching operations which, in one aspect, is useful as a "through tubing" tubular patch system and has a body and a series of selectively expandable members which, once having passed through a tubular of a first diameter, are expandable in a tubular of a second diameter larger than the first diameter and then operable to expand a liner patch to seal a leak in the tubular of the second diameter. Such a system may be used in a tubular disposed within a wellbore or in a tubular on the earth surface.

Abstract: A perforating gun connector is provided for downhole use in oil and gas fields. The perforating gun connector includes a stinger and a stinger receptacle. The stinger is adapted to be stabbed into the stinger receptacle. A loaded engaging member movable between a running position before the stinger is stabbed into the stinger receptacle and a latched position when the stinger is stabbed into the stinger receptacle to latch the stinger and the stinger receptacle together. A release member retains the loaded engaging member in the running position. When the stinger is stabbed into the stinger receptacle and a set force is applied to the stinger and stinger receptacle, the release member releases the loaded engaging member to move to the latched position and latch the stinger and the stinger receptacle together. According to a second aspect of the invention, the perforating gun connector is releasable, further including a releasable stop member to stop the engaging member in the latched position.

Abstract: A method and apparatus for servicing a Christmas tree on a completed well as set forth. It incorporates a tub or bucket which fits around the casing below the Christmas tree. With the use of chilled liquid in the tub, a cold temperature region is created. A chilled water supply is connected through a flexible injection line, injection orifice, and is sprayed into the Christmas tree to flow downwardly through the chilled region. And ice plug is formed on the interior of the pipes defining the casing and production tubing strings. Ice is formed from the exterior to the interior, thereby plugging the well and enabling servicing.

Abstract: Perforations and other openings in well casings, liners and other conduits may be substantially blocked or sealed to prevent fluid flow between the casing or liner interior and an earth formation by placing a radially expansible sleeve adjacent the perforations or openings and urging the sleeve into forcible engagement with the casing or inner wall using an explosive charge. An apparatus including a radially contracted sleeve formed by a coiled plate member or a tubular member having flutes defined by external and internal folds, may be deployed into a well casing or liner through a production or injection tubing string and on the end of a flexible cable or coilable tubing. An explosive charge disposed on the apparatus and within the sleeve may be detonated to urge the sleeve into forcible engagement with the casing inner wall.

Abstract: A method for zone isolation or replacing a damaged or corroded casing with a solid plastic is described herein. A resin/curing agent mixture sufficient to form a hardened plastic or solid, underwater and/or at low wellbore temperatures that is also able to withstand downhole stresses, is placed into the wellbore so as to bind with the undamaged casing and close off any thief zone. Subsequently, the resin/curing agent mixture forms a hardened solid. The hardened solid is milled out if necessary so as to form a resinous casing the size of the original casing. Later, the hardened resinous casing is perforated to communicate with a targeted zone. Perforation is not required when isolating a zone. The hardened solid is of a strength sufficient to withstand stresses generated during EOR operations such as carbon dioxide or steam-flooding. Said solid is also resistant to workover acids and other chemicals used in EOR operations.

Abstract: A method and apparatus for repairing or isolating holes, ruptures, splits or old perforations in marginal oil and gas wells from producing perforations. The apparatus includes two packer assemblies, a tube assembly and a slip assembly. The packer assemblies further include expandable packer elements and a vent cone mounted on a mandrel. The mandrels of the packer assemblies are connected to opposite ends of the tube assembly. The slip assembly is housed on the mandrel of one packer assembly and is used to create a positive mechanical set of the repair apparatus when positioned over the damaged area. Once the packer apparatus is positioned and the packer elements expanded, gas from producing formations flow to the wellhead through the tube assembly without interfering with the operation of down-hole pumps. The length of the gas vent packer apparatus can be varied between the packer elements depending upon the depth of damaged casing requiring repair or isolation.

Abstract: The present invention relates to a method of terminating undesirable gas migration in a well through one or more passages such as channels and microannuli in the cement sheath holding the casing in the well bore. The methods basically comprise forming one or more lateral openings through the casing and the cement sheath into a substantially gas impermeable formation penetrated by the well bore. One or more horizontal fractures are created in the formation extending from the lateral openings, and a fluid which sets into a substantially gas impermeable solid is deposited in the openings and fractures. The fluid is permitted to set into a substantially gas impermeable solid in the openings and fractures whereby passages in the cement sheath are plugged and gas migration is terminated.

Abstract: To seal the connection between an internal lining and external borehole, casing or pipeline, one or more elastically deformable annular seals are placed on the preform in a contracted state, in a configuration which does not impede insertion of the preform into the borehole, casing or pipeline. During expansion of the preform the seal itself forms an annular groove for receiving it in the exterior surface of the preform. After hardening of the preform a rigid lining is obtained having an integral seal. Applications include repair of boreholes, casings, especially in oil wells, or pipelines, by internal lining.

Abstract: This invention provides a method and system for logging an earth formation with a logging tool that is stuck (lodged) in a well bore traversing the earth formation while fishing for the stuck logging tool. This procedure is accomplished by re-establishing communication between the stuck logging tool and surface equipment during the fishing process. Communication is established by reconnecting the electrical conductors in the supporting cable after the cable has been severed in order to install fishing equipment in the well bore around the cable supporting the logging tool. The procedure to reconnect the electrical conductors requires identifying conductors in each end of the severed cable and appropriately matching conductors from each cable end to achieve electrical communication. Once there is electrical communication between the stuck logging tool and surface logging equipment, logging procedures can be continued even during the fishing for the stuck logging tool.

Abstract: A method of lining a casing affixed in a well bore for repairing breaches in the casing with a continuous string of tubular polymeric material is provided. The tubular polymeric material has an outer diameter greater than the inner diameter of the casing. The outer diameter of the tubular polymeric material is reduced and such reduced material is injected into casing such that the polyethylene pipe remains in a reduced state until the polyethylene pipe is run to a preselected depth. After the polyethylene pipe is run to the desired depth, the reduced pipe is allowed to rebound thereby forming a fluid tight seal with the casing and effectively sealing any breaches in the casing.

Abstract: A sintered metal screen is releasably suspended from a packer mandrel by a locking mandrel and a landing nipple. The sintered metal screen and locking mandrel are retrievable with the assistance of a running tool which is insertable into the bore of the locking mandrel. According to this arrangement, the sintered metal sand screen may be removed and replaced without retrieving the packer or the production tubing. In one embodiment, the sintered metal screen is enclosed within the bore of a sliding side valve. The sliding side valve may be opened and closed as desired for selectively admitting formation fluid from various producing zones, or for isolation of a damaged screen. In another embodiment, an auxiliary sintered metal screen is inserted into the bore of a primary screen, for example, a conventional wire-wrap sand screen.

Abstract: A method for zone isolation or replacing a damaged or corroded casing with a solid plastic is described herein. A resin/curing agent mixture sufficient to form a hardened plastic or solid, underwater and/or at low wellbore temperatures that is also able to withstand downhole stresses, is placed into the wellbore so as to bind with the undamaged casing and close off any thief zone. Subsequently, the resin/curing agent mixture forms a hardened solid. The hardened solid is milled out if necessary so as to form a resinous casing the size of the original casing. Later, the hardened resinous casing is perforated to communicate with a targeted zone. Perforation is not required when isolating a zone. The hardened solid is of a strength sufficient to withstand stresses generated during EOR operations such as carbon dioxide or steam-flooding. Said solid is also resistant to workover acids and other chemicals used in EOR operations.

Abstract: A longitudinally spaced series of tubular nipple structures are installed in a well flow conductor operatively extended through a subterranean well bore. Each nipple structure has a thinned-wall, increased interior diameter longitudinal section through which a plurality of fluid flow openings laterally extend, and an interior side surface annular tool locator recess, with each such recess having a profile different than those of all of the other tool locator recesses. The thinned-wall longitudinal sections of the nipples facilitate the formation of the flow openings therein. To seal off the flow openings in any selected one of these longitudinal nipple sections, a radially expandable tubular metal patch is supported on a setting tool which is lowered into the well flow conductor. A locator member complementarily and lockably receivable by the locator recess of the selected nipple is also supported on the tool.

Abstract: A method for zone isolation, profile modification, remedial cementing, or replacing a damaged or corroded casing with a solid plastic is described. A solidifiable epoxy resin mixture, containing a critical amount of a hardener and curing agent for improved pumpability, is placed into a wellbore so as to bind with undamaged casing and close off any thief zones. Subsequently, the epoxy resin mixture forms a hardened solid underwater and/or at low wellbore temperatures that is able to withstand downhole stresses. The hardened solid is milled out if necessary so as to form a resinous casing the size of the original casing. Later, the hardened resinous casing is perforated to communicate with a targeted zone. Perforation is not required when isolating a zone. The hardened solid is of a strength sufficient to withstand stresses generated during EOR operations such as carbon dioxide or steam-flooding. Said solid is also resistant to workover acids and other chemicals used in EOR operations.

Abstract: Well casing is repaired using a guide string for maintaining contact with a lower casing section disposed in the well, particularly an open hole portion of such well. The guide string is connected to a swivel and milling tool and lowered into the casing section remaining in the open hole portion of the well for machining the upper end of the casing section. The swivel prevents build-up of angular momentum of the guide string which may decouple the guide string from the milling tool when the milling tool rotatably decelerates or snags during the machining or milling operations. The milling tool and swivel may be retrieved and the guide string, with a safety joint or fishing head, reinserted in the well during installation of a new casing section.

Abstract: Method of completing an uncased section (10) of a borehole (1) in an underground formation (2) comprising the steps of:(a) placing at a predetermined position in the borehole (1) a slotted liner (11) provided with overlapping longitudinal slots (12);(b) fixing the upper end of the slotted liner (11); and(c) moving upwardly through the slotted liner (11) an upwardly tapering expansion mandrel (15) having a largest diameter which is larger than the inner diameter of the slotted liner (11).

Abstract: A method and apparatus for reaming foreign deposits from the flow passage of well production tubing and cleaning deposits from the completion profiles within the tubing as well as for drifting the production tubing while located within a well bore. A reaming tool is extended through the tubing string and is rotated for reaming operations. A plurality of reaming dogs of the tool are selectively and radially expanded to tubing and tubing completion profile reaming positions by cams of a hydraulically operated linearly removable actuator mandrel. The actuator mandrel is spring-urged toward a position permitting spring-urged retraction of the reaming dogs so that the reaming tool may be introduced into or withdrawn from the tubing string by linear movement.

Abstract: According to the invention, the tubular preform is radially deformable between a longitudinally folded state and substantially cylindrical unfolded state to form a length of rigid tube in situ. The preform comprises a flexible and watertight inner envelope (6) whose peripheral extent is equal to the internal extent of the length of tube, and, formed on the outside of said inner envelope, reinforcement (2) made of filamentary structure comprising a plurality of fibers impregnated with a settable resin, including fibers (3) oriented mainly in the peripheral direction of the preform, each of these fibers (3) extending over more than one turn and co-operating with adjacent fibers by making contact therewith such that adjacent fibers can slide over one another while the preform is in any state other than its unfolded state where, under internal pressure, the fibers are locked together by the friction between them due to a capstan effect.

Abstract: A method for continuing a measuring operation using a sonde immobilized in the well which method involves lowering, concentric to the cable, a length of tubular elements until the sonde is engaged by a special coupling fitted at the end of the length of tubular elements, the length of tubular elements serving to protect the cable. In addition, a coupling at an upper end of the length of tubular elements is equipped with a lateral window to minimize maneuvering time. After engagement, the sonde is used to carry out measurements by displacing the length of tubular elements.

Abstract: A method for replacing a damaged or corroded casing with a solid plastic is described herein. After removing the corroded or damaged casing from the wellbore, the borehole is underreamed to a desired diameter. Thereafter, a resin/curing agent mixture sufficient to form a hardened plastic or resin able to withstand downhole stresses, is placed into the wellbore so as to bind with the undamaged casing and close off any thief zone. Subsequently, the resin/curing agent mixture forms a hardened solid. The hardened solid is milled out so as to form a resinous casing the size of the original casing. Later, the hardened resinous casing is perforated to communicate with a targeted zone. Perforation is not required when isolating a zone.

Abstract: An emergency casing hanger can be lowered over casing collars and into a wellhead housing to support a string of casing. The casing hanger has a slip bowl which is slotted so that it can be radially expanded to insert over the casing collar. Slips are carried in the interior of the bowl for gripping the casing once the slip bowl is in position. The running tool has an inner sleeve that holds the slips in a retracted position and holds the slip bowl in an expanded position until the slip bowl clears the collar. Once the running tool has been removed, a honing tool is then lowered over the casing. The honing tool has honing stones mounted in a housing and biased inward for smoothing the exterior of the casing to receive a seal.

Abstract: An apparatus is disclosed for perforating, testing, and repairing casing in an earth borehole. A device is moveable through the casing. The device can be mounted on a wireline, on tubing, or on both. A perforator is mounted in the device for producing a perforation in the casing. The device will also generally include components for hydraulic testing/sampling from the formations behind the casing. A plugger is mounted in the device for plugging the perforation with a solid plug or a non-solid sealant.

Abstract: An apparatus for providing access to the casing of a burning oil well near the wellhead includes a sled-like carriage which is moved over the ground surface into a position straddling the well casing. A heat shield carried by the sled shields personnel and equipment thereon from the well fire. An excavator is mounted on the sled behind the heat shield for movement toward and beneath the heat shield to excavate a cavity around the well casing. A platform apparatus on the sled, including a pair of jaws openable to allow receipt of the casing, covers the excavated cavity into which a known well plugging device is moved for attachment to the well production pipe after the outer casing is cut away.

Abstract: In a well treatment method, a fluid is positioned in a wellbore have formation perforations in alignment with the portion thereof to be treated. A gas generator is positioned in proximity with the fluid and is actuated to disperse the fluid within the wellbore in accordance with a pressure/time relationship. In the preferred embodiment of the invention, the fluid is a fluid resin material which is polymerized following operation of the gas generator to form a consolidated, porous, permeable matrix which retains sand and other fine materials while permitting the flow of production fluid into the well.

Abstract: This invention relates to a method of repairing holes, channels, voids and microannuli in a cement sheath situated in the annular space between a casing and the wall of a wellbore penetrating a subterranean earth formation, which method involves the use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement, which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.

Abstract: This invention relates to a method of repairing a hole in and thereby terminating the undesirable flow of fluid through a hole in a casing disposed in a wellbore penetrating a subterranean earth formation which method involves the same use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement, which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.

Abstract: Gas leakage from oil wells through casing thread connections and other small leakage spaces is reduced or eliminated by injecting into the lift gas flowstream a sealant composition comprising a carrier liquid, such as diesel fuel or water, an ethoxylated phenol surfactant and particulate silica and/or Gilsonite. A liquid sealant composition is injected into oil wells on artificial gas lift comprising arctic diesel fuel, a surfactant and solubilized Gilsonite in a weight ratio of about 10:1 diesel fuel to Gilsonite and diesel fuel to surfactant, respectively. Effective reduction in leakage flow rates is obtained over a relatively short time period (one to ten hours).

Abstract: The arrangement for patching off troublesome zones in a well has a string of profile pipes with cylindrical portions at their ends, and a device for setting the string of profile pipes in a well, mounted for longitudinal reciprocation inside the string of profile pipes.Said device includes a reamer of the cylindrical portions of the profile pipes, positioned inside the uppermost cylindrical portion of the string of profile pipes, rigidly connected with an expander positioned above the string of profile pipes and having a housing with expanding elements mounted thereon.

Abstract: An improved device and process for creating a lining in a bore transfers strip wrapped in overlapping spiral fashion about a mandrel to the bore wall such that the edge-to-edge relation of the spirally-wrapped strip is maintained from the mandrel to the bore wall. Adhesive is applied to the strip surface during wrapping thereof on the mandrel. The invention provides a new bore with a thin, strong, corrosion resistant lining over a preselected portion of its length that is substantially pressure tight internally and externally and leak proof thus permitting substantial reuse of the lined bore.

Abstract: A body of shape memory metal is placed within a tubing by a running sub which transports the body to a desired location within the tubing while the shape memory metal is in its martensitic phase whereupon the shape memory metal is heated so as to regain its original shape which is tailored to its application inside the tubing.

Abstract: A geothermal wellhead repair unit including a mechanically set packer to isolate the wellhead for removal and repair thereof. The packer is run into the well string using a running tool. The packer is set by placing tension on the mandrel to set the packing elements and the slip assembly. Once the packer is set, the running tool can be disengaged without fear of collapsing the packer and the wellhead removed for repair or replacement. Upon replacement of the wellhead, the running tool can be used to unset and retrieve the packer.

Abstract: A geothermal wellhead repair unit including a mechanically set packer to isolate the wellhead for removal and repair thereof. The packer is run into the well string using a running tool. The packer is set by placing tension on the mandrel to set the packing elements and the slip assembly. Once the packer is set, the running tool can be disengaged without gear of collapsing the packer and the wellhead removed for repair or replacement. Upon replacement of the wellhead, the running tool can be used to unset and retrieve the packer.

Abstract: A downhole pump filter filters sand and other solid particles from well fluids prior to passage of the fluids through the intake nut of a well pump. A cylindrical coupling has an externally threaded upper end which coaxially screws into the pump intake nut. The coupling also has an externally threaded lower end. A tubular member coaxially secured within the lower end of the coupling has a plurality of perforations dispersed at least along its lower portion. A filter sock may encase the perforated portion of the tubular member to block smaller sand or other solid particles from entry into the tubular member perforations. A cylindrical casing with a closed lower end and an internally threaded upper end coaxially screws onto the exxternally threaded lower end of the coupling with the tubular member and the filter sock disposed within the casing. The casing has a plurality of perforations dispersed at least along its lower poriton.

Abstract: The method of well construction includes the steps of drilling the rock and consolidating it with a conductor casing, a surface casing string and a flow string, and isolating the troublesome zones of the well with profile pipes being reamed in the course of their setting. The reaming of the profile pipes is effected by building up a pressure drop across them and subsequently expanding them. The drilling of the rock after the casing-in of the well with the conductor casing and the surface casing string is preformed with a bit of one and the same diameter, with the troublesome zones being reamed to a diameter equalling the outer diameter of the reamed profile pipes which are successively set in all the troublesome zones of the well as they are exposed by the drilling.

Abstract: The process involves creating an internal lining in a bore, e.g., for repairing well casings. A plurality of layers of resilient strip material having an adhesive material, in uncured condition and interspersed between overlapping surfaces of the strip material and between the outer surface thereof and the bore, are applied in spiral fashion by means of a mandrel to the portion of the bore to be lined. Pressure is then applied to the internal surface of the liner to force the liner against the inner surface of the bore, preferably by inflation of a packer or packer assembly whose length is substantially the length of the liner, until the adhesive is cured. The mandrel for creating the liner in a bore includes a portion adapted to receive the spirally-wrapped strip material, a packer at the upper end of the wrappable portion of the mandrel and a packer terminating at the lower end of the wrappable portion of the mandrel and extending therebelow.

Abstract: An improved device and process for creating a lining in a bore transfers strip wrapped in overlapping spiral fashion about a mandrel to the bore wall such that the edge-to-edge relation of the spirally-wrapped strip is maintained from the mandrel to the bore wall. Adhesive is applied to the strip surface during wrapping thereof on the mandrel. The invention provides a new bore with a thin, strong, corrosion resistant lining over a preselected portion of its length that is substantially pressure tight internally and externally and leak proof thus permitting substantial reuse of the lined bore.

Abstract: The invention relates to a compact valve removal tool with a fixed crosshead (18) to be mounted on a pipeline end, such as a wellhead spool outlet (3), and a moving crosshead (19) which is axially slidable, the fixed crosshead accommodating an axially slidable and rotatable rod (16) and gripping means (50) for holding the rod, and the moving crosshead having drive means (23, 24) for advancing and retracting it to enable rod extension pieces (17) to be fitted or removed, the fixed crosshead also having safety stops (58) movable into the line behind the rod or behind a rod extension to block the path of the rod if the griping means failed. Preferably, the moving crosshead (10) cooperates with further safety means (60-72) to prevent operation of the gripping means except in predetermined, safe positions. The tool could be useful for operations other than plug insertion, such as milling a valve gate.

Abstract: Thread leaks, small holes, and leaks around packers in well casings and production tubing are repaired by applying a compressed foam mixture which includes discrete solid particles of various sizes for forcing the suspended particles into the opening to provide a high friction seal. The foam mixture is moved along the inside of the conduit sandwiched between fluid bodies for maintaining the foam mixture intact. Back pressure is applied to the foam mixture for aiding the mixture to be forced through the openings.

Abstract: The invention relates to a method and apparatus for relining bores such as oil wells, using multiple layers of spiral wrapped, resilient lining material which expands to form a continuous liner for the bore.