Abstract: The present invention generally relates to a cutting insert for use with wellbore milling tools. The cutting insert forms an angle between a milling surface of the insert and a surface of the tool that the insert is attached to in order to provide the proper cutting incline, and substantially perpendicular sides of the insert relative to the milling surface of the insert provide continuous support for the milling surface. In addition, the inserts can comprise spacers and legs that evenly distribute bonds formed between inserts and bonds formed between the inserts and the surface of the tool, respectively. Selecting the dimensions of the spacers and legs alters the strength of the bonds.

Abstract: The present invention generally relates to a cutting insert for use with wellbore milling tools. The cutting insert forms an angle between a milling surface of the insert and a surface of the tool that the insert is attached to in order to provide the proper cutting incline, and substantially perpendicular sides of the insert relative to the milling surface of the insert provide continuous support for the milling surface. In addition, the inserts can comprise spacers and legs that evenly distribute bonds formed between inserts and bonds formed between the inserts and the surface of the tool, respectively. Selecting the dimensions of the spacers and legs alters the strength of the bonds.

Abstract: A wellbore mill system having a first mill with a main body with a top end and a bottom end, milling structure on the main body, and a hook portion projecting from the bottom end of the main body for supporting at least one member below the first mill, the hook portion having a lip. One such system has a whipstock having a top lug, the top lug resting on the lip of the hook portion of the first mill, the top lug having a hole therethrough, the hook portion of the main body of the first mill having a hole therethrough, a shear stud with a portion extending through the hole in the top lug and a portion extending through the hole in the hook portion thereby releasably securing the first mill to the whipstock.

Abstract: A system has been invented for cutting wellbore casing and retrieving casing and a wellbore device connected thereto, the system, in one aspect, including engaging apparatus for releasably holding the wellbore device, casing cutting apparatus interconnected with and below the engaging apparatus for cutting casing in a wellbore, the wellbore device connected to the casing, and locking apparatus for selectively and releasably locking the engaging apparatus holding the wellbore device. In one aspect the engaging apparatus has one or more movable latching arms for releasably holding a wellbore device, e.g. but not limited to a wellhead and the arms are mounted below a top bonnet that holes therethrough so that the flushing of debris and/or cutting from the tops of the arms is facilitated. In one aspect, a drain sub is used to reduce flow to the casing cutter so that the circulation of debris and/or cuttings is inhibited.

Abstract: Wellbore operations (e.g. for milling and/or drilling) are disclosed which require a reduced number of tool trips into a wellbore to create a cut-out pocket, opening, or window in a tubular such as casing in the wellbore; and, in some aspects, to continue into a formation adjacent a main wellbore forming a lateral wellbore in communication with the main wellbore. Preferably one trip is required to complete a window or a window and the lateral wellbore. In one aspect a full gauge tool body is used so that the completed lateral wellbore is of a substantially uniform diameter along its entire length, which, in one aspect is suitable for the passage therethrough of full gauge tools, pipe, devices, and apparatuses. In one aspect a cutting system has cutting apparatus initially covered with a wearable away material which is worn away by contacting a tubular to be milled, exposing the cutting apparatus for milling and/or for drilling formation adjacent the wellbore.

Abstract: New systems and methods have been invented for explosively forming openings, ledges, windows, holes, and lateral bores through tubulars such as casing, which openings may, in cerain aspects, extend beyond the casing into a formation through which a wellbore extends. In certain aspects openings (e.g. ledges, initial, or completed windows) in wellbore tubulars (e.g. tubing or casing) are made using metal oxidizing systems, water jet systems, or mills with abrasive and/or erosive streams flowing therethrough and/or therefrom.

Abstract: A wellbore sidetracking method has been invented which includes, in certain embodiments, milling out a casing section from a cased, cemented wellbore; placing a deflection device, e.g. a whipstock, so that, upon pivoting of the upper concave portion of the whipstock at least a top portion thereof extends up into and abuts casing above the milled out section and, in certain aspects, a portion of the whipstock also extends down into and abuts casing below the milled out section; introducing a mill into the wellbore to mill out a part of the casing above the milled out section which would interfere with the introduction of a drill bit; removing the mill; introducing a drilling system into the wellbore to be deflected into the milled out area; and drilling a new sidetracked bore with the drilling system from the milled out area. In one aspect a mill is provided which mills out the part of the casing above the milled out area without contacting the formation or with only minimal contact thereof.

Abstract: The present invention, in one embodiment, discloses a whipstock system having an orientation device; a flexion member releasably secured to the orientation device; co-acting lower and upper body members, the lower body member interconnected with the flexion member; a connecting bar which connects the upper and lower body members permitting the upper body member to move downwardly with respect to the lower body member while preventing separation of the two body members; and a concave member secured to and above the upper body member. In one preferred embodiment, one or more movable pawls on the connecting bar move to engage surfaces on one or both body members to prevent upward movement of the upper body member with respect to the lower body member, or conversely movement of the lower body member downwardly away from the upper body member; and movement of the one or more pawls in contact with both body members also forces the two body members apart further stabilizing the system in a tubular.

Abstract: A whipstock assembly which includes a guide section and a setting section, wherein the setting section is configured to facilitate slight rotation of said setting section when the whipstock is set within a well, which rotation urges the guide section securely against the sidewall of the wellbore. Setting section includes a surface which will serve as a fulcrum, and a radially moveable element which serves to apply a force to one side of the whipstock, allowing the whipstock assembly to move as a lever, wherein the guide section is caused to meet the wellbore sidewall.

Abstract: The invention relates to an improved drill string member having at least one spiral groove formed in its outside surface and incorporating a combination of engineering considerations and criteria such that the invention member will have an extraordinarily high performance capacity in directional drilling. The invention member can make bends in the well on radii as short as 25-50 feet and is particularly suitable for operation together with downhole motor driven bits.