Abstract: A downhole assembly comprises a whipstock and an expandable anchoring tool connected to the whipstock, wherein the tool comprises a body including a plurality of angled channels formed into a wall thereof and a plurality of moveable slips, wherein the slips translate along the angled channels between a collapsed position and an expanded position. A method for performing a thru tubing operation in a well bore comprises running a downhole assembly comprising a whipstock and an expandable anchoring tool in a collapsed position through a first diameter section of the well bore, orienting the whipstock, and translating a plurality of pairs of slips of the expandable anchoring tool to an expanded position into gripping engagement with a casing lining a second diameter section of the well bore that is larger than the first diameter section, wherein the pairs of slips are axially spaced apart along the expandable anchoring tool.

Abstract: The whipstock face below the mounting lug is initially curved with a fairly long radius to protect the whipstock body initially. After moving down the minimally sloping curved face a transition to a greater angle is presented to increase the lateral forces on the window mill and to force the mill laterally to exit the tubular through the window. The transition after the curved portion is preferably to a flat inclined surface to the ramp bottom.

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: The present invention relates to a downhole method and apparatus for locating a window in a wellbore casing and determining the depth and orientation of said window. Apparatus of the present invention comprises a body (4) and a window engaging member (6) mounted on said body (4) so as to be movable between a retracted position and an extended position. The engaging member (6) is adapted to project into a wellbore window when in the extended position during use and is further adapted to engage with a first position of said window in such a way that, when pressed against said window portion, the engaging member (6) tends to slide along wellbore edge defining said window portion so as to locate the engaging member (6) centrally in said window portion before preventing movement of the apparatus in the direction of pressing. The invention thereby allows the depth and orientation of a window in a wellbore to be determined.

Abstract: An assembly for sidetracked drilling in a wall of a borehole previously drilled or cored in a formation includes a guide element and an expansible device fixed to the front end of the guide element operable to be selectively expanded by an actuation means. A sidetracking channel is formed in the guide element in alignment with an internal space, upstream of the expansible device in the direction of advance. A longitudinal cavity is formed in the guide element parallel to the longitudinal axis and arranged to allow passage from the internal space to the actuation means of the expansible device. Within the internal space of the guide element, an external tube of the core barrel includes a core bit fixed to the front end of the external tube and arranged to slide, after having been released, in the internal space and in the sidetracking channel and then progress to the formation.

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: 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 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: 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 downhole tool is disclosed that functions as an expandable anchoring tool, capable of passing through a restricted wellbore diameter while in a collapsed position and thereafter translating to an expanded position for grippingly engaging a larger wellbore diameter. An embodiment of the tool includes a body including a plurality of angled channels formed into a wall of the body and a plurality of moveable slips. The plurality of moveable slips translates along the plurality of angled channels between a collapsed position and an expanded position. The slips may include a plurality of extensions corresponding to and engaging the plurality of channels.

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 whipstock assembly includes a tubular anchor 36 which is expanded into engagement with the casing string 8, and a tubular expander 24 which is forcibly moved into the tubular anchor to expand the tubular anchor downhole into secure engagement with the casing string. The tubular anchor and tubular expander remain downhole. An orientation sleeve 18 at the upper end of the expander 24 includes an orientation surface 20. A whipstock 70 engages the sleeve 18 to orient the whipstock face for diverting a tool into a hole in the side of the casing string. Once the whipstock 70 is removed from the well, the orientation sleeve may receive a sealing nipple 130 at the lower end of a production tubing string.

Abstract: One or more subterranean zones are isolated from one or more other subterranean zones using a combination of solid tubulars and perforated tubulars.

Abstract: An assembly for sidetracked drilling in a wall of a borehole previously drilled or cored in a formation includes a guide element and an expansible device fixed to the front end of the guide element operable to be selectively expanded by an actuation means. A sidetracking channel is formed in the guide element in alignment with an internal space, upstream of the expansible device in the direction of advance. A longitudinal cavity is formed in the guide element parallel to the longitudinal axis and arranged to allow passage from the internal space to the actuation means of the expansible device. Within the internal space of the guide element, an external tube of the core barrel includes a core bit fixed to the front end of the external tube and arranged to slide, after having been released, in the internal space and in the sidetracking channel and then progress to the formation.

Abstract: The present invention relates to methods and equipment for recovering use of a well-bore in circumstances where the well bore has become blocked by downhole equipment. The invention provides a method comprising the steps of separating, at a release joint, a portion of equipment from a jammed portion (6) of equipment; running the separated portion of equipment uphole out of the wellbore (100); running a deflector assembly (60) downhole into the wellbore (100); and deflecting a milling tool (64) from the wellbore into surrounding formation. The method is characterised by restricting relative movement between the deflector assembly (60) and the wellbore (100) by engaging, prior to deflecting the milling tool (64), the deflector assembly (60) with said jammed portion (6) of equipment.

Abstract: A section mill is positioned below an exit guide in a drill string assembly used to mill a section of steel casing below the whipstock and which as the section mill moves down and mills along the section of casing, causes the whipstock to be lowered down adjacent the milled-out casing and allows the drill bit and drill string to be run along the surface of the exit guide and into the earth formation. Alternatively, the section mill is positioned above the exit guide in a drill string assembly after the section mill has milled out in an appropriate length of the steel casing, the tubing string pulls both the section mill and the exit guide up to a position where the exit guide is adjacent the area of formation which has been exposed by milling along the steel casing.

Abstract: A sealed multilateral junction system provides fluid isolation between intersecting wellbores in a subterranean well. In a described embodiment, a method of forming a wellbore junction includes the steps of sealing a tubular string in a branch wellbore to a tubular structure in a parent wellbore. The tubular string may be secured to the tubular structure utilizing a flange which is larger in size than a window formed in the tubular structure. The flange may be sealed to the tubular structure about the window by a metal to metal seal or by adhering the flange to the tubular structure.

Abstract: The present invention provides apparatus and methods for controlling and/or powering downhole components without the need for control and/or power lines extending from the components to the surface of the well and without the need for power or control lines to be inserted into the wellbore along with the components. In one aspect of the invention, a borehole is lined with a casing, the casing having at least one aperture disposed. Adjacent the aperture, on the outer surface of the casing, is a docking station, which is permanently attached to the casing and includes a socket. After the casing is installed in the borehole, a downhole component can be lowered into the wellbore. The downhole component is equipped with a connector extending from an outer surface thereof. The connector assembly is disposable through the aperture in the casing and, the connector assembly can be connected to the socket of docking station.

Abstract: A downhole force generator (60) adapted to be moved to a target location within a wellbore (70) for interaction with a well tool (74) previously positioned in the wellbore (70) comprises a downhole power unit (62) having a moveable shaft (68). An anchor (64) is operably associated with the downhole power unit (62). The anchor (64) has an anchoring configuration and a running configuration. In the anchoring configuration, the anchor (64) longitudinally secures the downhole force generator (60) within the wellbore (70). An operating tool (66) is operably associated with the downhole power unit (62) and is operably engageable with the well tool (74) such that when the operating tool (66) is operably engaged with the well tool (74) and the anchor (64) is in the anchoring configuration, movement of the moveable shaft (68) will transmit a force to the well tool (74).

Abstract: The present invention relates to downhole drilling operations, and more particularly, to the completion of lateral boreholes. Apparatus (100) is provided comprising a tubular liner portion (108) for lining a portion of a lateral borehole adjacent an opening of a borehole into the lateral borehole. An end portion of said tubular liner portion (108) is provided with a flange element (102) having a curved surface for locating in abutment with an area of main borehole surrounding said opening. A method of using said apparatus (100) is also provided.

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: In accordance with one embodiment of the present invention, a method for drilling wellbores includes drilling a main wellbore and disposing a casing string in the main wellbore. The casing string has a deflecting member and a sealing member coupled thereto. The method further includes disposing a drill string having a drill bit coupled at a lower end thereof in the casing string and drilling, from the main wellbore, a first lateral wellbore at a first depth with the drill bit. The method further includes removing the drill bit from the first lateral wellbore, transferring the casing string and the drill bit to a second depth that is higher than the first depth, drilling, from the main wellbore, a second lateral wellbore at the second depth with the drill bit, and preventing, using the sealing member, a fluid from the first lateral wellbore from flowing above approximately the second depth while drilling the second lateral wellbore.

Abstract: In accordance with one embodiment of the present invention, a method for drilling wellbores includes drilling a main wellbore, disposing a casing string having a deflecting member at a lower end thereof in the main wellbore, disposing a drill string having a drill bit at a lower end thereof in the casing string, and drilling, with the drill bit, a first lateral wellbore at a first depth in the main wellbore. The method further includes transferring the casing string to a second depth in the main wellbore that is less than the first depth, disposing a first temporary plug in the main wellbore at the second depth to prevent gas from flowing up the main wellbore past the second depth, transferring the casing string to a third depth in the main wellbore that is less than the second depth, and drilling, with the drill bit, a second lateral wellbore at the third depth.

Abstract: The present invention provides an apparatus and methods for seating a whipstock. The apparatus comprises an expandable seat, or nipple, configured to receive a whipstock. The seat is run into a cased wellbore, and is set by expanding it into frictional contact with the inner surface of the casing. Thereafter, a whipstock is seated onto the seat. The seat includes a keyway configured to receive an orientation member extending from the whipstock. In this manner, the orientation of the seat can be determined. An orientation member of the whipstock can be adjusted to properly orient the face of the whipstock in the seat, and the whipstock lowered onto the seat so that it automatically seats in the proper direction. The whipstock then serves as a diverter tool for drilling a lateral wellbore such as a horizontal well.

Abstract: A whipstock assembly includes a whipstock body 8 having a whipstock center of gravity offset radially from the central axis of the whipstock body, a counterweight to releasably secured to the whipstock body, with a counterweight having an offset counterweight center of gravity, an orientation device 5, and a neutralizer 11. The neutralizer causes the combined whipstock/neutralizer center of gravity to be substantially closer to the central axis of the whipstock body compared to the whipstock center of gravity. An attaching mechanism 6, 12 allows the neutralizer to be returned to the surface after the whipstock body is set in the well.

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 lockable motor assembly for use in a well bore comprises a PDM motor having a rotor and a stator. A locking member has a splined projection which is received within a splined recess of the rotor and external splines which mate with splines provided on a sub connected to the stator. The components are held in this configuration by a shear ring until the fluid pressure within a chamber defined between the locking member and the sub is sufficient to cause the shear ring to shear. The locking member may then move out of the engagement with the rotor to free the motor for operation. The locking member is held in this position by a ratchet mechanism.

Abstract: Apparatus and methods for anchoring and orienting equipment in a well provide a latch assembly having a substantially unobstructed bore, thereby increasing access and flow therethrough while the latch assembly is operatively engaged with an anchoring and orienting profile in the well. The latch assembly may include a generally tubular collet structure having multiple collets integrally formed thereon.

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: An apparatus for drilling one or more holes at an angle to a wellbore. The apparatus includes a tubular housing defining one or more openings. Each opening is configured to provide an exit through which a drilling assembly drills to form a hole at an angle to the wellbore. The apparatus further includes one or more deflectors. Each deflector defines a surface for guiding the drilling assembly through an opening, and each deflector is positioned inside the tubular housing such that the surface is facing the opening. The apparatus further includes an anchor having a bottom portion attached to a top portion of the tubular housing and having a top portion configured to be removably fixed to a conveyance tubular.

Abstract: A gravel packing system for re-entry of a screen assembly by a completion tool having an inflate packer as an isolation barrier for minimizing the necessary height of the gravel pack within the casing and thus maximizing the production interval of a well to permit a higher rate of production. The invention assures re-entry of tools to a gravel pack screen assembly for well completion following a gravel pack operation. A guiding and anchoring tool is run through a casing restriction and/or well tubing to a desired position below the restriction and/or tubing and within the casing and is actuated for anchoring. Guide fingers are formed downhole into a tool guiding configuration and the tool is left anchored within the well casing. Subsequently, a well completion tool is and guided into and latched within the guiding and anchoring tool and the inflate packer is set to enable optimum well production.

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 method of anchoring a whipstock on the mill or drill body using an anchor extendible to engage an eyelet formed or provided on the whipstock to run in a mill and whipstock in one trip. The anchor is retractable into the body of the drill so that the drill can pass by the whipstock during lateral drilling and out the casing wall without interference. The anchor preferably is extended and retracted by hydraulic force controlled remotely by the operator. The anchor is preferably shaped to match and conform to the outer wall of the drill so that in the closed position, the anchor is contiguous with and does not extend beyond the outer diameter of the drill body. Part of the drill body is preferably removed to allow the anchor to nest within the space provided by the removal of the drill body.

Abstract: A latching system for maintaining the position of a component within a downhole drill string section during operation of a drill string. One preferred latching system embodiment has a shoe member including a cavity for receiving a component, a chamber opening into the shoe member cavity, an engagement member movable in the chamber between a retracted position and an engagement position, a first passage in fluid communication with the chamber and extending to an end surface of the shoe member, and a second passage extending from an outer side surface of the shoe member to the first passage. A pressure differential between pressure in the first passage and pressure in the second passage alters the position of the engagement member.

Abstract: A sealed multilateral junction system provides fluid isolation between intersecting wellbores in a subterranean well. In a described embodiment, a method of forming a wellbore junction includes the steps of sealing a tubular string in a branch wellbore to a tubular structure in a parent wellbore. The tubular string may be secured to the tubular structure utilizing a flange which is larger in size than a window formed in the tubular structure. The flange may be sealed to the tubular structure about the window by a metal to metal seal or by adhering the flange to the tubular structure.

Abstract: This invention relates to a whipstock casing milling system and, more particularly, to such a system in which a window mill is secured to a whipstock so that the system may be run into a well, set and operated to open a window in a casing during a single trip. The milling system of the present invention comprises a protrusion (B) provided on the whipface of the whipstock wherein the protrusion (B) forms an extension of a relatively steep ramp surface (45) of the whipface so as to reduce damage to said surface (45) at a juncture (A) of said surface (45) with a relatively shallow ramp surface or parallel surface (46) during use of the system. The protrusion (B) thereby avoids an undercutting of a casing and a thinning of the whipstock.

Abstract: An apparatus and method for connecting a lateral well bore to a vertical well bore using a tieback liner while providing full bore access in the vertical well bore casing. The tieback liner is rotationally aligned with respect to a window of the casing by locating a key slot formed above the window and longitudinally aligned by using a no-go device to locate the bottom edge of the window. The tieback liner includes a snap sleeve that extends into a window of the main well bore casing and connects the tieback liner to the casing. The section of the casing receiving the snap sleeve is of a larger inner diameter than the other sections of casing. The connection between the tieback liner and casing prevents the tieback liner from rotating, tilting, or moving laterally with respect to the casing. The connection imparts significant resistance to formation loading applied at the junction.

Abstract: A one-trip through tubing window milling system is disclosed. The whipstock is delivered with the mill and downhole motor in a downhole assembly which further includes MWD equipment for proper whipstock orientation. The entire assembly is run through tubing and the MWD equipment orients the whipstock. A motor lock prevents the downhole motor from turning as fluid pressure is applied to properly anchor the whipstock below the production tubing. The motor lock is defeated and the milling commenced using the downhole motor. At the conclusion of the window milling, the bottom hole assembly, including the mill, is removed and a retrieving tool releases the whipstock for retrieval through the production tubing.

Abstract: A junction for the intersection of a main borehole and a lateral borehole includes a main tubular having a main window with a ramp aligned with the main window and a lateral tubular adapted to be telescopingly received within the main tubular and having a lateral window. The main tubular and lateral tubular each have an orientation surface. The lateral tubular has a first position with one end partially disposed within the main tubular. The lateral tubular is telescoped into the main tubular with the end of the lateral tubular engaging the ramp which guides the end of the lateral tubular through the main window and into the lateral bore. The orientation surfaces engage to orient the lateral window with the main window and form a common opening between the tubulars.

Abstract: A technique for facilitating the use of a variety of completion elements in a wellbore environment. The technique utilizes an insertion guide disposed within an open-hole section of a wellbore. The insertion guide may be radially expanded towards the surrounding formation to remove excess annular space. The expansion of the insertion guide further allows the use of a completion element having a greater diameter than would otherwise be afforded.

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: 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: 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: 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.

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.

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.

Abstract: Single horizontal wells drilled through heterogeneous reservoirs are capable of greater oil productivity than vertical wells, often with lower produced GOR with 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.

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.