Abstract: Wellbore apparatus has been invented which, in at least certain aspects, includes a wellbore apparatus having a tubular member with a top end, a bottom end, a hollow portion, and a window therethrough, a sleeve positioned within the hollow portion of the tubular member, the sleeve having a top end and a bottom end, a diverter apparatus within or outside the tubular member amd, optionally, below the bottom end of the sleeve, the sleeve movable so that the diverter, and the diverter directs the sleeve to the window and through the window into a bore extending beyond the window, and the window having an edge therearound to which the top end of the sleeve is weldable to sealingly secure the sleeve at the window.

Abstract: The reference member provides a permanent reference for the depth and orientation of all well operations and includes a body with an engaging surface for an attaching engagement to the interior surface of an existing casing in a borehole and an orienting surface for orienting well tools within the cased borehole. No sealing engagement is required with the casing. The engaging surface on the body has a first non-engaged position where the engaging surface does not engage the casing and an engaged position where the engaging surface does engage the casing which causes adequate engagement between the body and the casing to permanently dispose the well reference member within the casing. The well reference member further includes an actuation member for actuating the engaging surface from the non-engaged position to the engaged position.

Abstract: A method for controlling entry from a main bore of a casing into a lateral bore of a producing well which incorporates (i) means for surface-actuated flow control in the lateral bore (ii) a flow control means located in the casing adjacent to the lateral bore, and said method comprising the steps of: a) removing the flow control means when entry to the lateral bore is required, said flow control means having an internal passage allowing upward flow of produced fluid from the main bore and through said passage; b) mounting a locating nipple on the casing adjacent to the lateral bore; c) engaging the flow control means with the nipple to locate the flow control means in the casing; and d) providing diverter means in the casing which engages with and is orientable relative to the nipple and operates to guide entry to the lateral bore from above the nipple following removal of said flow control means.

Abstract: The retrieval tool includes a cylindrical member having a body, an inner passage, a guide cylinder and an engaging member. The engaging member may slide within the cylindrical member in order to engage a whipstock against an inner surface of the guide cylinder, facilitating removal of the whipstock from a borehole. A actuating member, piston, retainer and swivel sub may be used to connect the engaging member to the retrieval tool and enhance the mobility of the engaging member within the cylindrical member. A spring may also facilitate locking engagement of the engaging member and whipstock. Contact between the retrieval tool and the whipstock may lead to an increase of pressure within the inner passage, such pressure increasing the engagement between the engaging member and whipstock.

Abstract: Apparatus and methods are provided which enhance drilling and completion of wellbore intersections. In a described embodiment, a cutting tool diverter is used to drill a branch wellbore extending outwardly from a main wellbore. The diverter is provided with an outer easily millable portion which reduces the amount of time needed to retrieve the diverter. In another embodiment, a substance is injected into a formation surrounding the intersection of the main and branch wellbores, to thereby facilitate sealing of the intersection.

Abstract: A switch device (1) which sequentially conducts one hydraulic fluid stream (2) to two or more independently operated hydraulic units, where the switch device (1) with one or more channel throughputs (11, 12, 13 and 14) travels helically in a holding cylinder and transfers pressure streams in rotational sequence via fixed channels (8 and 8′) in the holding cylinder to separately operated hydraulic devices. With activation and deactivation in succession with alternate pressure and pressure relief combined with corresponding spring device (4), the switch device (1) in the surrounding cylinder is simultaneously forced to perform a one-way helical and axial forward and backward movement, resulting in altered fluid communication. Full switch rotation is achieved with, for example, six equiangular waves, each at 60°, or with six different angular waves, such as 90°+60°+45°+60°+60°+45°.

Abstract: A downhole system includes a deflector with a reaction surface that is engageable to a mill. The deflector is coupled to a motion mechanism that is activable to move the deflector generally along a longitudinal direction. During operation, the mill is engaged to a surrounding downhole structure, and the mill is rotated. As the mill cuts an opening in the downhole structure, the motion mechanism moves the deflector, which allows the mill to move with the deflector. A smooth motion is provided by the motion mechanism to enable a more accurate cutting of the downhole structure (e.g., casing or liner).

Abstract: A whipstock for mono-bore applications is disclosed which could be run in on wireline. The setting mechanism allows for a predetermined setting force to be applied to the anchor slip or slips before and automatic release from the running tool. The slips are further retained in position by a ratchet block, which is mounted to the whipstock body to work with the slips against release during removal of the milling equipment. The whipstock body is formed to place the upper end against the casing after the slips are driven out so that the onset of milling will not result in damage to the upper end. A retrieval tool engages an opening in the whipstock to release the grip of the slips and bring the assembly to the surface.

Abstract: The well reference apparatus and method of the present invention includes a reference member preferably permanently installed within the borehole at a preferred depth and orientation in one trip into the well. The reference member provides a permanent reference for the location of all operations, particularly in a multi-lateral well. The assembly of the present invention includes disposing the reference member on the end of a pipe string. An orienting tool such as an MWD collar is disposed in the pipe string above the reference member. This assembly is lowered into the borehole on the pipe string. Once the preferred depth is attained, the MWD is activated to determine the orientation of the reference member. If the reference member is not oriented in the preferred direction, the pipe string is rotated to align the reference member in the preferred direction. This process is repeated for further corrective action and to verify the proper orientation of the reference member.

Abstract: The present invention discloses a whipstock assembly for use in a wellbore to form a lateral wellbore therefrom. In one aspect, a whipstock is attached to a cutting tool by a shearable connection whereby the whipstock and cutting tool assembly may be run into the wellbore simultaneously. Upon compressive force from above, the shearable connection fails and the cutting action can begin. The shearable connection is designed to fail in compression but to withstand forces in tension brought about by the whipstock, accessories and extensions required to properly place the whipstock above a preset packer in the wellbore. In one aspect, the shearable connection means provides a first set of shearable members with equal shear resistance in tension and in compression. Another set of shearable members provide shear resistance against tensile forces but do not provide shear resistance against compressive forces.

Abstract: A method and apparatus for predictable downhole milling of a casing window having predetermined location, orientation, dimension and contour geometry. An elongate substantially rigid milling shaft has at least one casing window milling element in fixed relation therewith and has a pilot mill in articulated and rotary driven connection with the milling shaft. The milling shaft is in articulated and rotary driven connection with a rotary drive mechanism. The articulated connection of the pilot mill and milling shaft may incorporate an articulation control system to permit the pilot mill to be maintained substantially coaxial with the milling shaft so that its trajectory at a predetermined stage of window milling can be controlled by the milling shaft when positive guiding by a deflecting tool can no longer be ensured.

Abstract: A reference sleeve is used to orient a whipstock assembly to direct a pipe string into a new borehole section. The whipstock assembly may be removed such that a pipe string may enter the original borehole through the relatively large inner diameter of the expanded reference sleeve. The reference sleeve provides a permanent reference without forming an obstruction in the wellbore. To go back into the new borehole section, the whipstock assembly will be oriented automatically within the reference sleeve such that a pipe string will be reliably directed into the new borehole section, even years later. The reference sleeve is preferably run into the hole in a running position that is radially compressed. After orientation, the reference sleeve is expanded to thereby engage the wellbore and be affixed in position. Orientation surfaces include sloping guide surfaces and a slot that mate to a key on the whipstock assembly. The reference sleeve may be used for any reference purpose in the wellbore, e.g.

Abstract: The present invention discloses and claims a system for forming an opening, or window, in a downhole tubular for the subsequent formation of a lateral wellbore. In the system of the present invention, an apparatus is run into the parent wellbore which includes at least a tubular having a drill bit, a diverter such as a whipstock releasably connected to the drill bit, an anchoring device such as a packer, and a milling device. This apparatus allows for the milling of a window in the parent wellbore, and the drilling of a lateral wellbore through that window, in a single trip.

Abstract: The present invention generally provides an apparatus and method for forming a pilot hole in a formation. In one aspect of the present invention, the apparatus may comprise a starter mill connected to a bearing mill by a body joint. The apparatus may further comprise a lead bearing connected to a starter mill by a lead joint. Preferably, an outer diameter of the bearing mill is about the same as an inner diameter of a wellbore. As the lead bearing travels along the concave, the apparatus will bend between the bearing mill and the lead bearing. The bend urges the starter mill into contact with the wellbore wall. In another aspect of the present invention, a method for forming a pilot hole in a wellbore includes running a tool into the wellbore, the tool comprising a starter mill disposed between a first bearing and a second bearing. While running the tool along a concave of a whipstock, the tool bends between the first and second bearing and urges the starter mill to form the pilot hole.

Abstract: The present invention provides a method and apparatus for plugging a wellbore in a trip saving manner. In one aspect, the invention includes a cement retainer disposed on a run-in string and a radially expanded perforating assembly disposed below the cement retainer. In a single run, the apparatus provides for perforating a wellbore and squeezing cement through the perforations and into the formation therearound. In another aspect, a method of plugging the wellbore includes running a cement retainer and a radially expanded perforating assembly into a wellbore on a run-in string. After the cement retainer is set, a firing head is actuated to cause the perforating gun to discharge. After perforations are formed, cement is introduced from the cement retainer into the isolated area and squeezed through the perforations. Thereafter, the run-in string disengages from the cement retainer leaving behind the plug formed.

Abstract: A downhole drilling apparatus for interconnection in a casing or liner string having a drill bit disposed thereon for enabling the drilling of intersecting wellbores without removal of the drill bit is disclosed. In a disclosed embodiment, the apparatus comprises a housing having a window. A whipstock is disposed within the housing. Between the window and the whipstock is a filler. The whipstock and the filler define a central bore providing a fluid path through the apparatus. A back pressure valve may be disposed within the central bore to prevent back flow of fluids through the apparatus. Once the total depth of an initial wellbore is reached, the casing or liner string, including the apparatus, may be cemented in place. Thereafter, an intersecting wellbore may be drilled by laterally deflecting a second drill bit with the whipstock through the window of the housing.

Abstract: The well reference apparatus and method of the present invention includes a reference member preferably permanently installed within the borehole at a preferred depth and orientation in one trip into the well. The reference member provides a permanent reference for the location of all operations, particularly in a multi-lateral well. The assembly of the present invention includes disposing the reference member on the end of a pipe string. An orienting tool such as an MWD collar is disposed in the pipe string above the reference member. This assembly is lowered into the borehole on the pipe string. Once the preferred depth is attained, the MWD is activated to determine the orientation of the reference member. If the reference member is not oriented in the preferred direction, the pipe string is rotated to align the reference member in the preferred direction. This process is repeated for further corrective action and to verify the proper orientation of the reference member.

Abstract: The present invention discloses a whipstock assembly for use in a wellbore to form a lateral wellbore therefrom. In one aspect, a whipstock is attached to a cutting tool by a shearable connection whereby the whipstock and cutting tool assembly may be run into the wellbore simultaneously. Upon compressive force from above, the shearable connection fails and the cutting action can begin. The shearable connection is designed to fail in compression but to withstand forces in tension brought about by the whipstock, accessories and extensions required to properly place the whipstock above a preset packer in the wellbore. In one aspect, the shearable connection provides a first set of shearable members with equal shear resistance in tension and in compression. Another set of shearable members provides shear resistance against tensile forces but do not provide shear resistance against compressive forces.

Abstract: Method and apparatus for producing multiple zones from a single wellbore wherein a hollow whipstock is used to complete a lateral into an upper zone which lies above a lower producing zone. The whipstock has openings through its tapered face which, in turn, are sealed by dissolvable plugs (e.g. aluminum). Once the lateral has been completed, a reagent (e.g. hydrochloric acid) is pumped down the wellbore to dissolve the plugs and open the openings through the face of the whipstock thereby allowing the flow from the lower zone to pass through the whipstock to be produced up through the wellbore along with the flow from the upper production zone.

Abstract: A system and method for setting an anchor and/or whipstock attached to a downhole motor having a cutting tool attached to a tubular member, such as coiled tubing. In one aspect, the motor allows flow therethrough sufficient to actuate an upstream MWD or other position measuring tool, and an orienter if so equipped, and retain the orientation of the motor with the attached whipstock. An increased flow rate or pressure actuates the motor once the whipstock is set and rotation of the cutting tool or other equipment can begin.

Abstract: A method and apparatus for completing a junction of plural wellbores includes providing a casing junction assembly having plural outlets for communicating with corresponding wellbores. A tool has plural extendable conduits for engaging in the outlets. The casing junction assembly has an integral diverter with guiding surfaces to guide the conduits into the outlets.

Abstract: A liner hanger assembly has a slip actuation system which is locked for run-in. A piston assembly bolts onto the mandrel in a sealable manner to actuate a mechanical lock. Upon release of the lock, a plurality of springs actuate a sleeve which is in turn attached to the slips to move them relative to their slip seats. The slip seats are preferably mounted to the mandrel without welding and have longitudinal spaces for mud or cement flow therebetween. Load is distributed from each slip through its slip seat into the mandrel without interaction from an adjacent slip or slip seat. A rupture disk ensures that a predetermined pressure is built up before the piston can actuate to defeat the lock. The lock can come in a variety of configurations. One of which is a sliding sleeve over a dog and another is a yoke over a split ring which, when shifted, allows the split ring to expand, thus unlocking the parts.

Abstract: A method for controlling entry from a main bore of a casing into a lateral bore of a producing well which incorporates (i) means for surface-actuated flow control in the lateral bore (ii) a flow control means located in the casing adjacent to the lateral bore, and said method comprising the steps of:

Abstract: A system and method are disclosed for forming and reentering multiple lateral wells through a wall of a common well bore. The system includes an anchor, an orienting member, an extension member, a diverter and a probe releasably connected by one or more unilateral connections and a multilateral connection. The unilateral connection restricts rotational and translational movement of the system upon makeup, and maintains alignment between components thus joined in a single direction. The multilateral connection also restricts rotational and translational movement of the system upon makeup, however, enables alignment between components thus joined in multiple directions. Thus, use of the system enables lateral orientation of the diverter at multiple positions, positioning the diverter at multiple longitudinal positions and selective reentry of each lateral well formed.

Abstract: A downhole coiled tubing recovery apparatus and method which utilizes vibration and resonant vibration in particular, to remove coiled tubing and/or other objects which are stuck or jammed downhole in a well. In a preferred embodiment the coiled tubing recovery apparatus includes an oscillating apparatus suspended from a rig and fitted with a coiled tubing bail for mounting the coiled tubing and the method includes guiding the coiled tubing from a reel through the bail and into and from an injector head and the well, responsive to raising and lowering of the oscillating apparatus and the tubing bail. One or more rod clamps are typically used in connection with the coiled tubing bail for manipulating the coiled tubing through the injector head to and from the reel. In another embodiment of the invention the coiled tubing bail is omitted and the coiled tubing is suspended directly from a fitting attached to the oscillator and extends through the injector head into the well.

Abstract: An assembly for formation and completion of deviated wellbores is disclosed which includes a toolguide and a casing section which can be used together or separately. The toolguide includes a lower orienting section and a whipstock having a sloping face, commonly known as the directional portion of a whipstock. The toolguide is coated with a material such as epoxy or polyurethane to provide a repairable surface and one which can be removed to facilitate removal of the toolguide from the well bore. The lower orienting section has a latch which extends radially outwardly from the section and can be locked in the outwardly biased position.

Abstract: An assembly for formation and completion of deviated wellbores is disclosed which includes a toolguide and a casing section which can be used together or separately. The toolguide includes a lower orienting section and a whipstock having a sloping face, commonly known as the directional portion of a whipstock. The toolguide is coated with a material such as epoxy or polyurethane to provide a repairable surface and one which can be removed to facilitate removal of the toolguide from the well bore. The lower orienting section has a latch which extends radially outwardly from the section and can be locked in the outwardly biased position.

Abstract: Method and apparatus for producing multiple zones from a single wellbore wherein a hollow whipstock is used to complete a lateral into an upper zone which lies above a lower producing zone. The whipstock has openings through its tapered face which, in turn, are sealed by dissolvable plugs (e.g. aluminum). Once the lateral has been completed, a reagent (e.g. hydrochloric acid) is pumped down the wellbore to dissolve the plugs and open the openings through the face of the whipstock thereby allowing the flow from the lower zone to pass through the whipstock to be produced up through the wellbore along with the flow from the upper production zone.

Abstract: A method and apparatus for predictable downhole milling of a casing window having predetermined location, orientation, dimension and contour geometry. An elongate substantially rigid milling shaft has at least one casing window milling element in fixed relation therewith and has a pilot mill in articulated and rotary driven connection with the milling shaft. The milling shaft is in articulated and rotary driven connection with a rotary drive mechanism. The articulated connection of the pilot mill and milling shaft may incorporate an articulation control system to permit the pilot mill to be maintained substantially coaxial with the milling shaft so that its trajectory at a predetermined stage of window milling can be controlled by the milling shaft when positive guiding by a deflecting tool can no longer be ensured.

Abstract: A whipstock assembly and method of operation is disclosed that automatically orients itself within a wellbore to a known first rotational position. The whipstock assembly is mounted on bearings that permit free rotation of the whipstock assembly within the wellbore. Due to gravitational forces, the eccentric weight load of the whipstock will automatically orient itself on the low side of the wellbore. Most wellbores are angled and the angle, azimuth, depth and other information about the wellbore is known so that the operator will know what position the whipstock assembly will automatically assume. A lower orientation section of the whipstock assembly is clamped into that first rotational position such as by a lower packer and/or slips. The whipstock is then rotated to the desired orientation by reciprocating the wellbore string. The whipstock is then clamped into the desired rotational position by activating an upper packer and/or slips. The running tool is removed and drilling or milling can be initiated.

Abstract: A combined casing mill and whipstock or other exit guide is positioned in a drill string assembly used to mill a section of steel casing, which as the section mill mills along the section of casing, allows the exit guide to be transported adjacent the milled-out casing and allows a drill bit and drill string to be run along the surface of the exit guide and into the earth formation. In an alternative embodiment, the combination of the section mill with the exit guide is used in open hole operations having no casing.

Abstract: In one embodiment, the invention relates to a method for location, or location and entry, of a lateral wellbore from a main wellbore of a multilateral hydrocarbon well, the method being characterized by unique operation of a controllably bent sub. The invention further relates to a system for location, or location and entry of a lateral wellbore, including a specialized controllably bent sub, and most preferably, to a controllably bent sub designed for efficient lateral wellbore location and/or entry.

Abstract: The reference member provides a permanent reference for the depth and orientation of all well operations and includes a body with an engaging surface for an attaching engagement to the interior surface of an existing casing in a borehole and an orienting surface for orienting well tools within the cased borehole. No sealing engagement is required with the casing. The engaging surface on the body has a first non-engaged position where the engaging surface does not engage the casing and an engaged position where the engaging surface does engage the casing which causes adequate engagement between the body and the casing to permanently dispose the well reference member within the casing. The well reference member further includes an actuation member for actuating the engaging surface from the non-engaged position to the engaged position.

Abstract: The invention provides an apparatus for actuating a downhole tool by utilizing a pressure differential created by fluid flowing through a conduit. The conduit is in communication with a pressure sensing line that is selectively exposable to areas of the conduit having different pressures. By exposing the pressure sensing line to a portion of the conduit having a predetermined pressure therein, the pressure sensing line causes actuation of a hydraulic tool therebelow.

Abstract: The side tracking system includes a window mill having a full diameter cutting surface and a reduced diameter tapered cutting surface and a whipstock having a ramp engaging the reduced diameter cutting surface. The materials of the whipstock have a first cutablity and the materials of the casing have a second cutability. The reduced diameter cutting surface contacts the whipstock ramp at a first contact area and the full diameter cutting surface contacts the wall of the casing at a second contact area. As weight is applied to the mill, there is a first contact stress at the first contact area and a second contact stress at the second contact area. A cutability ratio is the first cutability divided by the second cutability and a contact stress ratio is the first contact stress divided by the second contact stress. The mill cuts the casing rather than the whipstock by maintaining the product of the cutability ratio and the contact stress ratio less than one.

Abstract: A wellbore casing, including a casing section, for deployment in a subterranean wellbore. The casing section includes a pre-milled windowed opening. A liner is disposed within the casing section covering the window opening from the inside. In addition, a rigid material is disposed outside of the casing section covering the window opening. A filer is located intermediate the casing section and the liner. The liner, filler and rigid material prevent cement from affecting the window opening when the casing section is being cemented in the wellbore.

Abstract: A method and apparatus for creating multiple branch wells from a parent well is disclosed. According to a first embodiment of the invention a multiple branching sub is provided for placement at a branching node of a well. Such sub includes a branching chamber and a plurality of branching outlet members. The outlet members, during construction of the branching sub, have previously been distorted into oblong shapes so that all of the branching outlet members fit within an imaginary cylinder which is coaxial with and substantially the same radius as the branching chamber. According to one embodiment, the distorted outlet members are characterized by an outer convex shape. In another embodiment, the distorted outlet members are characterized by an outer concave shape when in a retracted state. After deployment of the branching sub via a parent casing in the well, a forming tool is lowered to the interior of the sub.

Abstract: The present invention relates to a method and a device to stabilize the production of oil wells. The device is used in a tubing of an oil well and it is intended to overcome the harmful effects provoked by the unstable flow of multiphase flows which are produced by some oil wells.

Abstract: A whipstock assembly 10, 110 for setting within a casing C includes a whipstock body 12, 112 having a whipstock diversion face 24, 124 for diverting a tool with respect to the casing. At least one wedge member 32, 132, 133 is moveable relative to the whipstock body and supports one or more wedge slips, 34, 36, 134, 136 thereon for anchored engagement with the casing. The wedge member has a whipstock body engaging surface 98 for sliding engagement with a lower wedge engaging surface 96 on the whipstock body. An elongate rod or other actuation member 40 moves the at least one wedge member from the run in position to the set position. According to the method of the invention, the whipstock and anchor assembly may be run into the well through a tubing string then set in the casing. The whipstock assembly may be of the type which is retrievable to the surface after having been set in the casing.

Abstract: An assembly for formation and completion of deviated wellbores is disclosed which includes a toolguide and a casing section which can be used together or separately. The toolguide includes a lower orienting section and a whipstock having a sloping face, commonly known as the directional portion of a whipstock. The toolguide is coated with a material such as epoxy or polyurethane to provide a repairable surface and one which can be removed to facilitate removal of the toolguide from the well bore. The lower orienting section has a latch which extends radially outwardly from the section and can be locked in the outwardly biased position.

Abstract: An assembly for formation and completion of deviated wellbores is disclosed which includes a toolguide and a casing section which can be used together or separately. The toolguide includes a lower orienting section and a whipstock having a sloping face, commonly known as the directional portion of a whipstock. The toolguide is coated with a material such as epoxy or polyurethane to provide a repairable surface and one which can be removed to facilitate removal of the toolguide from the well bore. The lower orienting section has a latch which extends radially outwardly from the section and can be locked in the outwardly biased position.

Abstract: A method and apparatus to from a branch well includes a branching sub defining a branching chamber and multiple branching outlet members connected to the branching chamber. A stiffening structure or rib is provided at least at a juncture between two of the branching outlet members. The stiffening structure is adapted to reduce deformation of the branching chamber at the juncture as the branching outlet members are being deformed (such as being expanded).

Abstract: Apparatus for boring a hole from an inside of a casing outwardly at an angle relative to a longitudinal axis of the casing comprises a drill shoe having a longitudinal axis and being positionable in the casing, the shoe having first and second passageways which converge into a third passageway exiting the shoe, a torsional load transmitting element and a cutting element connecting to one end of the torsional load transmitting element, the torsional load transmitting element and cutting element being positioned in the first passageway during non-use and in the third passageway during use, and a fluid conduit and a nozzle connected to one end of the fluid conduit, the fluid conduit and nozzle being positioned in the second passageway during non-use and in the third passageway during use.

Abstract: A method and apparatus for creating multiple branch wells from a parent well is disclosed. According to a first embodiment of the invention a multiple branching sub is provided for placement at a branching node of a well. Such sub includes a branching chamber and a plurality of branching outlet members. The outlet members, during construction of the branching sub, have previously been distorted into oblong shapes so that all of the branching outlet members fit within an imaginary cylinder which is coaxial with and substantially the same radius as the branching chamber. According to one embodiment, the distorted outlet members are characterized by an outer convex shape. In another embodiment, the distorted outlet members are characterized by an outer concave shape when in a retracted state. After deployment of the branching sub via a parent casing in the well, a forming tool is lowered to the interior of the sub.

Abstract: A method and apparatus for creating multiple branch wells from a parent well is disclosed. According to a first embodiment of the invention a multiple branching sub is provided for placement at a branching node of a well. Such sub includes a branching chamber and a plurality of branching outlet members. The outlet members, during construction of the branching sub, have previously been distorted into oblong shapes so that all of the branching outlet members fit within an imaginary cylinder which is coaxial with and substantially the same radius as the branching chamber. According to one embodiment, the distorted outlet members are characterized by an outer convex shape. In another embodiment, the distorted outlet members are characterized by an outer concave shape when in a retracted state. After deployment of the branching sub via a parent casing in the well, a forming tool is lowered to the interior of the sub.

Abstract: A milling system has been invented for milling an opening in a tubular in a tubular string in a wellbore extending down from a surface of the earth, the milling system, in one aspect, has a whipstock connected to an anchor assembly and a mill apparatus releasably connected to the whipstock, the mill apparatus having auto fill apparatus therein. A mill has been invented with a mill body with a top end and a bottom end, a flow bore through the mill body, and an auto fill apparatus in the flow bore. A valve assembly has been invented for selectively controlling fluid flow through a hollow tubular in a string of hollow tubulars in a wellbore extending from a surface of the earth into the earth, the valve assembly in one aspect having positions limited to at rest, circulate, and anchor set positions so that a fluid pressure indicating at the surface indicates only either a pressured up position for anchor setting or a pressured up position for fluid circulation.

Abstract: An assembly for formation and completion of deviated wellbores is disclosed which includes a toolguide and a casing section which can be used together or separately. The toolguide includes a lower orienting section and a whipstock having a sloping face, commonly known as the directional portion of a whipstock. The toolguide is coated with a material such as epoxy or polyurethane to provide a repairable surface and one which can be removed to facilitate removal of the toolguide from the well bore. The lower orienting section has a latch which extends radially outwardly from the section and can be locked in the outwardly biased position.

Abstract: Methods and apparatus are described for forming a window of optimum dimensions in casing wall. A window of maximum width is cut when the center line of the mill tool is located inside of the inner diameter of the casing where a maximum amount of casing is drilled away by the mill tool. A whipstock is described which deviates the mill tool outwardly so that the center line of the mill tool is in approximately this position. The whipstock then maintains the mill tool at this approximate location until a window of desired length is cut having a substantially maximum width.

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

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.