Abstract: Embodiments of the present invention generally provide methods and apparatus for forming a tubular-lined wellbore which does not decrease in diameter with increasing depth or length. Methods and apparatus for forming a substantially monobore well while drilling with casing are provided. In one aspect, a portion of a second casing is expanded into a portion of a first casing having a larger inner diameter than the remaining portion of the first casing string. In another aspect, the portion of the second casing is expanded into a portion of the first casing having a compressible member therearound. In another aspect, a lined lateral wellbore may be constructed by forming a lateral wellbore extending from a main wellbore lined with casing. A diameter of at least a portion of the lateral wellbore may be expanded. An expandable tubular element may be run into lateral wellbore and expanded to have an inner diameter equal to or larger than an inner diameter of the main wellbore casing.

Abstract: A weight spacer apparatus has a carrier which is tubular in shape and a spacer tube which is also tubular in shape for insertion into the carrier. The weight spacer apparatus also has a plurality of weight bars which may be inserted into the spacer tube after the spacer tube is inserted into the carrier and which are also removable from the spacer tube. In one embodiment, a weight tray is inserted into the spacer tube for receiving the weight bars, and the weight tray may be fabricated from half-round tubing with a welded plate to cover the diametric opening. In another embodiment, a center plate is attached inside the spacer tube along the length of the spacer tube to divide the spacer tube into first and second compartments.

Abstract: A wireline drill train is used to drill an elongated, small diameter, lateral branch borehole from near the base of a main well. The drill train, includes a drill module, a first self-propelled thrust module coupled to the drill module, and a second self-propelled thrust module pivotally coupled to the first self-propelled thrust module. Each thrust module includes at least two extendible thrusters. Each extendible thruster includes a six-bar mechanism and a traction tread. The drill train further includes a first articulated linkage linking the first self-propelled thrust module to the drill module, and a second articulated linkage linking the second thrust module to the first thrust module. The second articulated linkage includes a thrust-transmission bar and three retractable stiffener bars.

Abstract: A method is shown for fracturing a subterranean formation from a deviated well bore. A plurality of spaced fracture initiation points are created in the well bore. Hydraulic pressure is applied to all of the sets of perforations at the fracture initiation points to extend a plurality of spaced fractures in the formation in directions substantially perpendicular to the deviated well bore direction. The same perforated interval in the wellbore is shot two or more times, using a conventional perforating gun in order to achieve a desired hole count over a shorter distance. The perforating technique is combined with a pumping protocol which better insures that the fracturing fluid being pumped flows more evenly through each set of perforations upon the application of hydraulic pressure rather than the majority of the fluid entering only the first perforated interval of the wellbore.

Abstract: A process for improved safety and productivity when undertaking oil recovery from an underground reservoir by the toe-to-heel in situ combustion process employing a horizontal production well. Water, steam, and/or a non-oxidizing gas, which in the preferred embodiment substantially comprises carbon dioxide which acts as a gaseous solvent, is injected into the reservoir for improving recovery in an in situ combustion recovery process, via either an injection well, a horizontal well, or both.

Abstract: A method of re-entering a previously-installed tubular in a lateral borehole from a primary borehole connected to the lateral borehole includes passing a downhole tool from the primary borehole into the lateral borehole, activating one or more radial thrust elements proximate to a nose portion of the downhole tool to apply a radial thrust to the downhole tool and lift the nose portion into alignment with the tubular, and inserting the nose portion of the downhole tool into the tubular.

Abstract: The present invention provides for high volume flow from a well. A retrievable formation isolation valve allows high volume flow through the remaining casing or tubing. Alternatively, a large bore valve configuration that is not retrieved, but remains as part of the casing, can be used. The present invention also includes methods to allow for high volume flow using retrievable isolation valves or large bore valves.

Abstract: A hydraulically actuated anchor and a mechanically actuated packer are used in combination to secure a production tubing system in a lateral prior to injection of a cement to line the lateral borehole in which the production tubing is positioned. The packer is expanded to prevent fluid cement material from flowing past the packer into a junction area of the lateral with other laterals and aid the removal of superfluous cement material after hardening of the injected cement material around the production tubing system.

Abstract: A well bore liner is carried on a working string into a main bore of a well. A well bore liner is directed from the main bore into an auxiliary bore of the well with a whipstock. The whipstock is coupled to a working string without withdrawing the working string from the main bore. The whipstock is then relocated in the well using the working string.

Abstract: A wellbore completion design is provided, which creates a convective flow action that separates water and sand from hydrocarbons during production of the hydrocarbons from a subterranean formation. A deviated section of the wellbore creates the desired effect. The wellbore completion design may include a secondary bore, which intersects the deviated section of the wellbore at an acute angle, to accumulate the separated water and sand. An injection pump disposed in the toe section of the secondary bore can also be employed to pump the water back into the water containing portion of the subterranean formation. If solids are present in more than trace amounts, the toe section of the secondary bore may be formed at an acute angle to the remaining portion of the secondary bore to prevent blockage of the pump. Alternatively, a tertiary bore may be provided, so that the solids can accumulate in the secondary bore and the water can flow into the tertiary bore.

Abstract: A well system for producing fluid from an earth formation. A primary wellbore section produces the fluid from the well system to the surface. The primary wellbore section includes a cylindrical member having a number of apertures. At least one flanking wellbore runs substantially alongside the primary wellbore section. The flanking wellbore is in fluid communication with the apertures on the primary wellbore section through the porous earth formation. At least one lateral wellbore section joins the flanking wellbore section. Formation fluid flows into the lateral wellbore sections and then into the flanking wellbore section. The fluid is then transmitted from the flanking wellbore, through the porous earth formation, and is received by the apertures in the primary wellbore section. The fluid flows through the primary wellbore section to the surface.

Abstract: A method for underground treatment of subsurface materials comprises providing an injection pattern and a recovery pattern, the injection pattern and the recovery pattern located proximate to a subsurface treatment zone and at least one of the injection pattern and the recovery pattern comprising a plurality of lateral bores extending from a main bore. A treatment solution is injected through the injection pattern and recovered through the recovery pattern.

Abstract: A method and apparatus for completing a lateral channel from an existing oil or gas well includes a well perforating tool for perforating a well casing at a preselected depth, and a lateral alignment tool for directing a flexible hose and blaster nozzle through a previously made perforation in the casing to complete the lateral channel. The disclosed apparatus eliminates the need to maintain the precise alignment of a downhole “shoe” in order to direct the flexible hose and blaster nozzle through a previously made perforation through the well casing.

Abstract: A subterranean zone can be accessed from the surface by forming a well bore extending from the surface into the subterranean zone. A tubing string is provided within the well bore, and an underreamer passed over the tubing string to a specified location within the subterranean zone. The underreamer is operated in forming an enlarged cavity in the well bore, and the subterranean zone about the tubing string is collapsed. Pressure within the enlarged cavity my be reduced to facilitate collapse of the subterranean zone about the tubing. The tubing string is provided with apertures, either before being positioned in the well or after, to allow passage of fluids into an interior of the tubing string. The fluids from the subterranean zone may be withdrawn through the tubing string.

Abstract: An apparatus for isolating a selected leg of a wellbore from the remainder of the wellbore includes a packer positionable in the selected leg of the wellbore, a tube extending through the packer from an uphole side of the packer to a downhole side of the packer to permit a fluid flow communication to the selected leg of the wellbore past the packer and a valve positioned in the tube to control fluid flow through the tube. In a method for isolating a selected leg of a wellbore, the apparatus is positioned in the selected wellbore leg and the packer set to permit fluid flow communication past the apparatus only through the tube and the valve of the apparatus.

Abstract: The present invention discloses a whipstock assembly (100) for use in forming a lateral borehole from a parent wellbore. The whipstock assembly comprises a body (122) and a deflection member 120) above the body. The deflection member includes a concave portion (111) for deflecting a milling bit during a milling operation. Disposed on a perforation plate (110) portion of the concave portion is a raised surface feature (116). The raised surface supports a milling bit above the perforation plate portion during a milling operation. This, in turn, substantially prevents frictional contact between the milling bits and the perforation plate portion during a milling operation. The present invention also provides a novel method for manufacturing a whipstock in which a cavity portion is formed behind the perforation plate by milling out the backside of the deflection member and then joining a second back cover member to the whipstock body to complete the assembly.

Abstract: A surface controlled subsurface lateral branch safety valve provides flow control for each branch wellbore in a multilateral well. In a described embodiment, a completion system for a well having an intersection between parent and branch wellbores includes an apparatus having multiple passages formed therethrough. One passage provides fluid communication between opposite ends of the apparatus in the parent wellbore, and another passage provides guidance for drilling the branch wellbore. The apparatus further includes a flow control device, such as a surface controlled subsurface safety valve, which selectively controls fluid communication with the branch wellbore.

Abstract: A modified toe-to-heel waterflooding (TTHW) process is provided for recovering oil from a reservoir in an underground formation. After establishing the conventional TTHW waterflood, the process includes placing a chemical blocking agent at the watered out producing toe portion of the horizontal leg of the production well to create a blockage in the producing toe portion and to create a new producing toe portion in an open portion of the horizontal leg adjacent the blockage through which most of the production takes place. Production is then continued through the new producing toe portion and the open portion of the horizontal leg of the production well. These blocking and producing steps can be continued to progressively block producing toe portions in a direction toward the vertical pilot portion of the production well.

Abstract: A system and method for assembly of downhole equipment in a subterranean well. In a described embodiment, a method of assembling an apparatus in a subterranean well includes the steps of: positioning an expandable shell in the well; expanding the shell in the well; and then interconnecting multiple portions of the apparatus to each other within the expanded shell.

Abstract: A method and apparatus for recovering viscous hydrocarbons from a subsurface reservoir holding the same using an essentially horizontal well bore having a production inlet and containing steam injection tubing that carries a plurality of jet nozzles oriented to emit steam along said injection tubing towards said production inlet.

Abstract: Methods of enhancing at least partially the structural integrity of a longitudinal portion of a deviated well bore are provided. The methods include providing a gravel matrix composition; providing a longitudinal portion of a deviated well bore; and placing a sufficient amount of the gravel matrix composition in the longitudinal portion to enhance the structural support of the longitudinal portion. Optional additives may include curable resins, tackifiers, and/or the incorporation of a degradable material in the gravel matrix composition.

Abstract: The present invention generally relates to an apparatus and method for improving production from a wellbore. In one aspect, a downhole pump for use in a wellbore is provided. The downhole pump includes two or more chambers for the accumulation of formation fluids and a valve assembly for filling and venting gas to and from the two or more chambers. The downhole pump further includes a fluid passageway for connecting the two or more chambers to a production tube. In another aspect, a downhole pump including a chamber for the accumulation of formation fluids is provided. In another aspect, a method for improving production in a wellbore is provided. In yet another aspect, a method for improving production in a steam assisted gravity drainage operation is provided. Additionally, a pump system for use in a wellbore is provided.

Abstract: In a WAG flood oil is displaced from a subterranean formation by injecting water alternately with gas into a single injection completion per pattern. The ratio of water to gas injected is the WAG ratio. In this invention, two separate injection completions are used in each pattern, with one placed directly above the other. A very low WAG ratio is used for injection into the bottom extremity of the formation. A very high WAG ratio is injected into the upper interval, at as high a rate as can safely be used without fracturing the formation. In the preferred embodiment, two horizontal well bores serve as the two completion intervals. Proper design of this method gives a vertical sweep efficiency of the gas that is several-fold greater than the best of previous WAG flood designs, especially in thin formations.

Abstract: A high pressure multiple branch wellbore junction. A wellbore junction system includes a wellbore junction with at least three bores extending therethrough. Exits of the three bores are axially spaced apart. At least two deflectors are formed on the wellbore junction. The deflectors are axially spaced apart, and each of the deflectors is aligned with a respective lateral exit of the bores.

Abstract: A system for lining a junction between a main bore and an auxiliary bore includes a first tubing adapted to line at least a portion of the main bore. The first tubing has a lateral opening therein. A second tubing has a junction shield extending outward therefrom. The junction shield has a larger transverse dimension than the lateral opening and is adapted to contract to a smaller transverse dimension to pass through the lateral opening into the auxiliary bore.

Abstract: A wellbore system for simultaneously drilling a wellbore into an earth formation and producing hydrocarbon fluid from the wellbore, is provided. The system comprises a production tubing extending into the wellbore and having a hydrocarbon fluid inlet arranged in a first part of the wellbore in fluid communication with a hydrocarbon fluid bearing zone of the earth formation, and a drilling riser extending through the production tubing and having a drilling fluid inlet in fluid communication with a second part of the wellbore, said second wellbore part being scaled from said first wellbore part. A drill string extends through the drilling riser and into said second wellbore part so as to allow further drilling of the wellbore.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: A gas restrictor for an intake of a horizontally oriented submersible well pump has a tubular housing and a number of apertures. A sleeve is mounted within the housing for rotation relative to the housing. The sleeve has an axially extending row of slots. At least one weight in the sleeve causes the sleeve to rotate to a position with the row of slots at the bottom of the sleeve while the well pump is oriented horizontally. The slots and apertures are arranged so that regardless of the particular orientation of the housing relative to the sleeve, at least one of the apertures will be in registry with one of the slots.

Abstract: A method and system of forming a lateral wellbore in a time and trip saving manner using a mill/drill to locate and place a casing window. In one aspect of the invention, a lateral wellbore is drilled with liner which is subsequently left in the lateral wellbore to line the sides thereof. In another aspect, the mill/drill is rotated with a rotary steerable system and in another aspect, the mill/drill is rotated with a downhole motor or a drill stem.

Abstract: A method for accessing a subterranean zone from the surface includes drilling a substantially vertical well bore from the surface to the subterranean zone and forming a slot cavity in the substantially vertical well bore proximate to the subterranean zone. The slot cavity comprises a substantially non-cylindrical shape. The method also includes drilling an articulated well bore from the surface to the subterranean zone. The articulated well bore is horizontally offset from the substantially vertical well bore at the surface and intersects the substantially vertical well bore at a junction proximate to the subterranean zone. The method may include drilling the articulated well bore to intersect the slot cavity of the substantially vertical well bore and drilling a substantially horizontal drainage pattern from the slot cavity into the subterranean zone. The subterranean zone may comprise a coal seam.

Abstract: A system for producing gas and water from a gas bearing strata during and after drilling completion. The system includes a directional drilling system, a main bore and pump. The directional drilling system includes a drill and a drill string. The main bore intersects the gas bearing strata and has an upper vertical portion, a lower horizontal portion and a curve portion connecting the vertical portion and the horizontal portion. Waste material collects temporarily until pumped to the surface by the pump installed in the bore.

Abstract: The invention provides a novel method of recovering oil by injecting oxygen into a chamber within an oil deposit thereby combusting oil at the chamber walls. The heated oil to drains towards the reservoir floor and is recovered oil via a production well.

Abstract: The present invention provides a method of recovering stranded oil wherein heated fluid is injected into a reservoir containing stranded oil in a region near the reservoir ceiling. The heated oil drains toward the reservoir floor and is recovered via a production well.

Abstract: A process for underbalanced drilling into multiple coal and shale formations, and dewatering the drilled formations, which includes drilling a first borehole through several coal seams to a certain depth; lowering an upstock on the end of a carrier string to the depth of the upper coal seam; lowering a drill string in the carrier string, and angling off of the upstock, to drill a lateral or horizontal borehole within the coal seam; repeating the process for the second coal seam; setting a packer in place above the first coal seam in the annulus between the cased borehole and the carrier string; forming perforations in the wall of the carrier string below the packer; retrieving the upstock from the carrier string; lowering an electrical submersible pump to the bottom of the principal borehole; pumping water from the sump portion to the surface within the annulus of the second drill string.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: A self orienting liner hanger system including a bent sub, an indexing sub in operable communication with the bent sub, a hanger assembly in operable communication with the indexing sub, and a profile connected with the hanger assembly. Yet further disclosed herein is a method for constructing a junction between a primary borehole and a lateral borehole. The method includes installing a window sleeve at the junction, running a liner hanger into the sleeve, cycling an indexing sub of the hanger until a bent sub of the hanger exits the window, and running the hanger into engagement with the sleeve.

Abstract: A short radius exit from a window milled in casing is possible using a whipstock with a sloping surface in excess of 3.5° and a window mill whose diameter is reduced to a percentage generally below about 95% of the casing inside diameter in a mono-bore or non-through tubing application. The system provides a greater flexibility in choosing the window location and eliminates having to penetrate adjacent formations as compared to previous techniques using a longer exit radius. The decrease in mill diameter, as compared to previous techniques, limits stresses on the milling equipment to minimize equipment failures during window milling and subsequent drilling of the lateral.

Abstract: A multi-layered wellbore junction. In a described embodiment, a method of forming an expanded chamber in a subterranean well includes the steps of: positioning multiple chamber sidewall layers in the well; and expanding the layers in the well to form the expanded chamber.

Abstract: A system for accessing a subterranean zone from an entry well including an entry well extending from the surface. The entry well has a substantially vertical portion. A one or more drainage wells extend from the entry well to a subterranean zone. A one or more articulated wells extend from the entry well to the subterranean zone. At least one of the articulated wells intersects at least one of the one or more drainage wells at a junction proximate the subterranean zone. A drainage pattern is formed coupled to the junction and operable to conduct fluids from the subterranean zone to the junction.

Abstract: A casing junction member connects in a well between a main casing and a lateral branch casing. The junction member has an upper end section which connects to the main casing extending above the member. It has a lower end section that is coaxial and connects into the main casing below the junction member. The junction member has a lateral section which extends downward for connecting to lateral branch casing. The junction between the main section and the lateral section has enlarged sections that are formed by opposed cones. A removable or drillable closure member blocks the lateral passage while in the collapsed and expanded positions. The casing junction uses internal fluid pressure to move from collapsed position to expanded position.

Abstract: A method and apparatus for completing a wellbore junction, wherein, in one embodiment, a first leg of a screen is fastened within a first tubular with a preformed window. The first tubular houses a whipstock with a cut-out portion containing a folded second leg of the screen. The first tubular is lowered into a junction of a central and a lateral wellbore. A second tubular is lowered within the first tubular and catches an end of the folded second leg of the screen thereby unfolding and expanding the screen as the second tubular is guided into the lateral wellbore.

Abstract: A sealed branch wellbore transition joint. In a described embodiment, a completion system for a well having a branch wellbore extending outwardly from a window in a parent wellbore includes a tubular string having a portion positioned within the window, and a sealing material on the tubular string portion. The sealing material swells in the well to thereby form a seal between the tubular string portion and the window.

Abstract: In accordance with one embodiment of the present invention, a method for lining a lateral wellbore includes drilling a main wellbore extending from a surface to a subterranean zone, casing the main wellbore with a main casing having a plurality of lateral wellbore windows formed therein, positioning a whipstock having a longitudinal bore running therethrough adjacent a respective one of the lateral wellbore windows, forming a lateral wellbore through the respective lateral wellbore window using the whipstock, lining the first lateral wellbore with a lateral liner and a portion of a tie-back assembly that has a pre-milled lateral wellbore window formed therein, aligning the pre-milled lateral wellbore window with the longitudinal bore, and coupling the tie-back assembly to the main casing.

Abstract: A formation testing tool is described herein, including a formation probe assembly having an extendable sampling probe surrounded by a cylindrical sleeve. The sleeve is configured to engage a metal skirt having an elastomeric seal pad coupled thereto. The skirt and seal are configured to be field replaceable. The elastomeric pad has a non-planar outer surface which engages a borehole wall in preparation for formation testing. The seal pad may be donut-shaped, having an aperture through the middle of the seal pad. The seal pad and its surface may include numerous different embodiments, including having a curved profile. The seal pad may also include numerous different embodiments of means for coupling the seal pad to the metal skirt. The formation testing tool also includes formation probe assembly anti-rotation means, a deviated non-circular flowbore, and at least one closed hydraulic fluid chamber for balancing fluid pressures.

Abstract: A highly flexible, wireline survey tool has roller knuckle joints that enable the survey tool string to penetrate and survey horizontal wells having inclinations of about 80° and more from vertical. The survey tool string includes a nose, roller stems, roller knuckle joints, and a highly accurate electronic gauge embedded in a roller cage. Each component has external wheels that are free to contact and roll when they make contact with the inner surfaces of the well. The wheels act as both friction-reducing elements and stand-offs for the survey tool string with respect to the inner surfaces of the well.

Abstract: A method and system of drilling straight directional and multilateral wells utilizing hydraulic frictional controlled drilling, by providing concentric casing strings to define a plurality of annuli therebetween; injecting fluid down some of the annuli; returning the fluid up at least one annulus so that the return flow creates adequate hydraulic friction within the return annulus to control the return flow within the well. The hydraulic friction should be minimized on the injection side to require less hydraulic horsepower and be maximized on the return side to create the desired subsurface friction to control the well.

Abstract: A method and apparatus that allows communications of electrical power and signaling from downhole component to another downhole component employs an inductive coupler assembly. In one arrangement, one portion of the inductive coupler assembly is attached to a production tubing section and the other portion of the inductive coupler assembly is attached to a casing or other liner section. The production tubing inductive coupler portion is electrically connected to a cable over which electrical power and signals may be transmitted. Such power and signals are magnetically coupled to the inductive coupler portion in the casing or liner section and communicated to various electrical devices mounted outside the casing or liner section. In other arrangements, inductive coupler assemblies may be used to couple electrical power and signals from the main bore to components in lateral branches of a multilateral well.

Abstract: A multilateral completion system utilizing an alternate passage. In a described embodiment, a wellbore junction includes a first passage extending from a first opposite end to a second opposite end of the wellbore junction. A window is formed through a sidewall of the wellbore junction and provides fluid communication between the first passage and an exterior of the wellbore junction. A second passage is in communication with the first passage on a first side of the window, and in communication with the first passage on a second side of the window.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: Single horizontal wells drilled through heterogeneous reservoirs are capable of greater oil productivity than vertical wells, often with lower produced GOR and WOR. Multiple drainholes tied-in to a vertical cased well are even more beneficial. Completion of such drainholes in many sandy reservoirs must use cemented liners. Well configurations comprising multiple drainholes liners, each of them tied-in to a vertical casing by pressure-tight connections require novel technologies making use of some novel downhole equipment, tools and procedures for drilling, tie-in and completion of such wells. These may be for newly-drilled wells or may be obtained by re-entry into an existing vertical cased well. Specific equipment, including novel casing joints, whipstocks, intermediate liners and tubing completion assembly components applicable to new wells are described herein.