Abstract: A section mill for milling wellbore tubulars has a tubular mill body, a pivotally mounted mill carrier having a beveled interior profile and a cutter blade on its exterior profile, and a translatable piston having an elongated driveshaft with a radially extending nose cone with a compression spring positioned around the elongated driveshaft. A hook on the elongated driveshaft configured to mate with a corresponding hook catch in the mill carriers maintains the mill carrier in a retracted position. The nose cone of the translatable piston moves upward and downward along the beveled interior profile of the mill carrier in response to fluid pressure. Rotation of the mill body rotates the attached mill carrier and cutter blade for milling.

Abstract: A cutting insert having an insert body with an upper surface. The upper surface of the insert body has an exterior cutting surface having an exterior cutting edge and an interior cutting surface having an interior cutting edge. The exterior cutting surface extends peripherally around and is coplanar with the upper surface of the insert body. The interior cutting surface is also coplanar with the upper surface of the insert body and is positioned within and is concentric with the exterior cutting surface. An exterior chip break separates the exterior cutting surface from the interior cutting surface.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: A section mill for milling wellbore tubulars has a tubular mill body, a pivotally mounted mill carrier having a beveled interior profile and a cutter blade on its exterior profile, and a translatable piston having an elongated driveshaft with a radially extending nose cone with a compression spring positioned around the elongated driveshaft. A hook on the elongated driveshaft configured to mate with a corresponding hook catch in the mill carriers maintains the mill carrier in a retracted position. The nose cone of the translatable piston moves upward and downward along the beveled interior profile of the mill carrier in response to fluid pressure. Rotation of the mill body rotates the attached mill carrier and cutter blade for milling.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: A multi-string section milling tool has a longitudinally extending tubular body with mill carriers carrying hardened cutters that pivotally extend from a mill window in the tubular body by upward movement of a drive plunger. A downwardly biased piston mounted to the upper end of a flow tube is slidably inserted through a stationary thimble below the piston. The lower end of the flow tube is attached to a drive plunger which is pivotally attached to drive yoke links pivotally attached the mill carriers. The piston and thimble creates a pressure chamber in the milling tool. Fluid pressure in the pressure chamber moves the piston, flow tube and drive plunger upward to pivotally extend the drive yoke links and mill carriers radially outward through the mill window. Cessation of fluid pressure in the pressure chamber retracts the mill carriers.

Abstract: A multi-string section milling tool has a longitudinally extending tubular body with mill carriers carrying hardened cutters that pivotally extend from a mill window in the tubular body by upward movement of a drive plunger. A downwardly biased piston mounted to the upper end of a flow tube is slidably inserted through a stationary thimble below the piston. The lower end of the flow tube is attached to a drive plunger which is pivotally attached to drive yoke links pivotally attached the mill carriers. The piston and thimble creates a pressure chamber in the milling tool. Fluid pressure in the pressure chamber moves the piston, flow tube and drive plunger upward to pivotally extend the drive yoke links and mill carriers radially outward through the mill window. Cessation of fluid pressure in the pressure chamber retracts the mill carriers.

Abstract: A casing mill for downhole casing milling has multiple elongated cutter bases hingedly connected to a main body by a plurality of positioning arms. An operating mechanism within the main body of the casing mill, actuated by fluid flow, moves the cutter bases to an extended position. Multiple cutters fixed to the cutter bases are then positioned to engage a casing surface. An internal fluid operated locking mechanism can be selectively actuated to secure the cutter bases in an extended position.

Abstract: A multi-string section milling tool has a longitudinally extending tubular body with mill carriers carrying hardened cutters that pivotally extend from a mill window in the tubular body by upward movement of a drive plunger. A downwardly biased piston mounted to the upper end of a flow tube is slidably inserted through a stationary thimble below the piston. The lower end of the flow tube is attached to a drive plunger which is pivotally attached to drive yoke links pivotally attached the mill carriers. The piston and thimble creates a pressure chamber in the milling tool. Fluid pressure in the pressure chamber moves the piston, flow tube and drive plunger upward to pivotally extend the drive yoke links and mill carriers radially outward through the mill window. Cessation of fluid pressure in the pressure chamber retracts the mill carriers.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: A casing section mill has a main body with cut-outs to accommodate casing section mill blades mounted thereon, and stabilizer inserts mounted in the cut-outs below the blades. The stabilizer inserts yield an outer diameter substantially the same as the drift inner diameter of the casing being milled, thereby providing positive centralization and stabilization of the blades. The casing section mill may be rotated by a downhole positioned positive displacement motor in the drillstring, by drillstring rotation from the surface, or a combination of downhole positive displacement motor and drillstring rotation.

Abstract: An apparatus for cutting and/or milling of tubulars in a wellbore, especially using coiled tubing. An elongated main body has a longitudinal bore, with a piston slidably positioned in the bore. The piston is connected to one or more operating arms which are rotatably connected to the main body. The connection between the piston and the operating arms may be a pinned connection or a geared connection, both of which provide for a positive connection between the piston and the operating arms. Cutter bases are connected to the cutter arms, with a number of cutters mounted to the cutter bases. Fluid flow down the coiled tubing and through the main body bore pushes the piston downwardly, opening the operating arms and cutter bases and permitting the apparatus to be pulled up into the lower end of a tubular string for cutting and/or milling.

Abstract: A downhole release mechanism for a drillstring. A first, uphole section and a second, downhole section comprise longitudinal bores and are rotationally locked together via a spline. A collet assembly is connected to the first section, with collet fingers extending into the bore of the second section when the first and second sections are joined. The collet fingers are biased outwardly, and an external shoulder on the collet fingers mates with an internal shoulder in the second section, locking the sections together. A piston is slidably disposed in a bore of the collet, and spring biased uphole. Fluid flow moves the piston to a downhole position, in which the collet fingers are held outwardly and the shoulders locked together. With fluid flow stopped, the piston moves uphole, and sufficient tension on the mechanism shears shear screws and snaps the collet fingers out the internal shoulder, releasing the mechanism.

Abstract: A casing mill for downhole casing milling has multiple elongated cutter bases hingedly connected to a main body by a plurality of positioning arms. An operating mechanism within the main body of the casing mill, actuated by fluid flow, moves the cutter bases to an extended position. Multiple cutters fixed to the cutter bases are then positioned to engage a casing end surface. Preferably, the cutters are arranged in vertically spaced apart rows, such that when one row is worn out in the milling process a visual indication is seen at the surface, as the casing mill drops to the next row of cutters.

Abstract: A downhole cutting tool for cutting sections or “windows” in tubular strings in wellbores has rotating cutters and a lower stabilizer section, both actuated by a fluid operated mechanism. The stabilizer section keeps the downhole cutting tool centralized in the tubular string. The cutters may have a robust profile and structure which enhances the window cutting function and permits passage of an operating rod to operate the stabilizer section.

Abstract: A casing mill for downhole casing milling has multiple elongated cutter bases hingedly connected to a main body by a plurality of positioning arms. An operating mechanism within the main body of the casing mill, actuated by fluid flow, moves the cutter bases to an extended position. Multiple cutters fixed to the cutter bases are then positioned to engage a casing surface. An internal fluid operated locking mechanism can be selectively actuated to secure the cutter bases in an extended position.

Abstract: A casing mill having a main body with cutter bases with cutters mounted on the cutter bases. The cutter bases are moved radially by operating arms which are rotatably attached to the main body, which are in turn moved by an operating mechanism in response to fluid flow through. One or more of the operating arms are extended to form a cutout arm, which enables cutting an initial window in a casing string, from which milling can continue. The operating arms are mounted to the main body by pins, which are held in the main body by a pin retaining arrangement.

Abstract: A casing mill having a main body with cutter bases with cutters mounted on the cutter bases. The cutter bases are moved radially by operating arms which are rotatably attached to the main body, which are in turn moved by an operating mechanism in response to fluid flow through. One or more of the operating arms are extended to form a cutout arm, which enables cutting an initial window in a casing string, from which milling can continue. The operating arms are mounted to the main body by pins, which are held in the main body by a pin retaining arrangement.