Abstract: The present invention discloses a whipstock assembly for use in forming a lateral borehole from a parent wellbore. The whipstock assembly comprises a body and a deflection member above the body. The deflection member includes a concave portion for deflecting a milling bit during a milling operation. Disposed on a perforation plate portion of the concave portion is a raised surface feature. 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 method of removing a restriction in a tubular located in a well includes providing a drilling assembly with a drill bit and a reamer, the reamer having a cutting structure for removing the restriction; drilling through a lower portion of the tubular; expanding the reamer at a location below the restriction; and urging the reamer back toward the restriction to remove the restriction.

Abstract: A method and apparatus for stabilizing a downhole tool during a downhole operation. The method and apparatus include a stabilizer having a stabilization member adapted to move between a retracted position and an extended position in order to engage a surface in a wellbore. The stabilizer also includes a plurality of actuators adapted to move the stabilization members from the retracted position to the extended position.

Abstract: Embodiments of the invention relate to an assembly for forming a cased well. The assembly may include an undercut drillable cementing shoe with a casing string connection at a first end. The shoe includes external tubing that forms a second end of the shoe and has a first section defining an enlarged inner diameter relative to a second section of the external tubing. The assembly may also include an earth removal member coupled to the second end of the shoe. The first section of the shoe is disposed between the earth removal member and the second section of the shoe. In another embodiment, the assembly may include a casing string having a first portion with a larger inner diameter than a second portion. The assembly may also include an earth removal member coupled to an end of the casing string. The first portion of the casing string is disposed between the earth removal member and the second portion of the casing string.

Abstract: A method is provided that allows the operator to re-enter a primary wellbore from a lateral wellbore after the lateral wellbore has been completed. The method generally comprises the steps of locating a cutting device such as a milling bit adjacent a tubular such as a liner within a wellbore, rotating the milling bit while maintaining an axial position of the milling bit relative to the liner to initiate an opening, and rotating and axially advancing the milling bit to complete the opening. In addition, a bottom hole assembly that facilitates re-entry into the primary wellbore from a lateral wellbore is provided. The bottom hole assembly generally includes a drill collar or other heavy pipe structure, and a mill. The mill has a body and cutting structures. The cutting structures apply lateral force against a surrounding pipe to form an initial lip through the wall of the pipe.

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 method of removing a restriction in a tubular located in a well includes providing a drilling assembly with a drill bit and a reamer, the reamer having a cutting structure for removing the restriction; drilling through a lower portion of the tubular; expanding the reamer at a location below the restriction; and urging the reamer back toward the restriction to remove the restriction.

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: The present invention discloses a whipstock assembly for use in forming a lateral borehole from a parent wellbore. The whipstock assembly comprises a body and a deflection member above the body. The deflection member includes a concave portion for deflecting a milling bit during a milling operation. Disposed on a perforation plate portion of the concave portion is a raised surface feature. 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 method and apparatus for stabilizing a downhole tool during a downhole operation is described herein. The method and apparatus include a stabilizer having a stabilization member adapted to move between a retracted position and an extended position in order to engage a surface in a wellbore. The stabilizer also includes a plurality of actuators adapted to move the stabilization members from the retracted position to the extended position.

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: 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: 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: A new wellbore apparatus has been invented which, in certain aspects, has anchor apparatus for anchoring the wellbore apparatus in a bore, the anchor apparatus actuated by fluid under pressure supplied thereto, and sealing apparatus selectively inflatable to close off the bore to fluid flow therethrough, and temperature compensating apparatus for maintaining a desired fluid pressure in the sealing apparatus to prevent it from bursting or deflating.

Abstract: A wellbore mill has been invented that, in certain aspects, has a body having a top and a bottom and, optionally, a fluid flow channel extending therethrough from top to bottom with, optionally, one or more fluid jetting ports in fluid communication with the fluid flow channel, milling apparatus on the body including a plurality of milling inserts, each insert mechanically secured in a corresponding recess in the body, said mechanical securement sufficient for effective milling in a wellbore. A wellbore milling method for milling an opening in a selected tubular of a tubular string in a wellbore has been invented that includes installing and using such a mill.

Abstract: A wellbore mill has been invented having a flexible main body, and at least one milling apparatus secured on the flexible main body. A wellbore mill has been invented having a main body with a top end and a bottom end, at least one milling structure on the mill body, and a stinger projecting down from and releasably secured to the bottom end of the mill body. Methods have been invented for milling wellbore tubulars with such mills. A method for eliminating tubular offset in a wellbore has been invented, and the method includes positioning a wellbore mill in a tubular offset of a tubular string in a wellbore, the wellbore mill comprising a flexible main body and at least one milling apparatus secured on the flexible main body, and rotating the wellbore mill to mill at least part of the tubular offset.

Abstract: A wellbore mill has been invented which has milling apparatus with a starting mill and a finishing mill, the starting mill having a central channel extending longitudinally therethrough, the central channel having an interior surface with carbide cutters thereon. A milling method has been invented for finishing a window in a casing in a wellbore, the window having been begun with a first mill, the method including inserting a second mill apparatus into the wellbore adjacent the window, the second mill apparatus having a milling system with a starting mill and a finishing mill, the starting mill having a central channel extending longitudinally therethrough, the central channel having an interior surface with carbide cutters thereon, rotating the second mill apparatus to finish the window.

Abstract: A wellbore motion control apparatus for controlling the motion of a tubular wellbore string (in one aspect with an additional item and/or apparatus connected thereto) in a wellbore extending from a surface down into the earth has been invented which has, in one aspect, a central mandrel connected to the tubular wellbore string, a housing with a hollow interior and fluid therein, at least one fluid passage apparatus disposable in the hollow interior and having a fluid flow channel extending therethrough, and the at least one fluid passage apparatus secured to the central mandrel, the housing surrounding the central mandrel, the at least one fluid passage apparatus disposed for movement in a chamber defined by an inner surface of the housing and an outer surface of the central mandrel, the at least one fluid passage apparatus positioned within the chamber so that fluid therein is flowable therethrough permitting movement of the fluid passage apparatus within the chamber and thereby controlling movement of the m

Abstract: Wellbore apparatus has been invented that includes a whipstock with a top and a bottom, the whipstock disposed in a wellbore extending down from an earth surface into the earth, the wellbore having an inner surface, a mill guide with a body having an upper end, a lower end, and a channel therethrough from the upper end to the lower end, and a portion of the lower end of the mill guide disposed between and held between the inner surface of the wellbore and an outer surface of the top of the whipstock.

Abstract: A wellbore motion control apparatus for controlling the motion of a tubular wellbore string in a wellbore extending from a surface down into the earth and methods for using it. Such an apparatus, in one aspect, has a housing with a top end, a bottom end, and a hollow interior having an interior volume with fluid therein. There is at least one fluid passage apparatus having a top end and a bottom end and disposable in the hollow interior of the housing, the at least one fluid passage apparatus having a fluid flow channel extending therethrough from the top end to the bottom end.