A wireline cutting tool. The wireline cutting tool comprises an elongated tubular body. A knife housing resides within the tubular body proximate an upper end, while a plunger resides within the tubular body proximate a lower end. An electric wireline passes through a bore of the knife housing and the plunger en route to an electrical connection sub. The electrical connection sub includes a pin that transmits signals from the electric wireline down to a downhole tool. The plunger is configured to slide up the bore of the lower sub in response to a first upward shear load applied by the wireline. This causes the plunger to act against knives residing within the knife housing. The knives are configured to travel up the bore of the upper sub in response to a second upward shear load applied by the plunger, pinching the wireline until severed. The second shear load is greater than the first shear load, creating a two-stage cutting tool.

A casing mill including a first milling configuration having a first blade for milling a first casing section, and a second milling configuration having a second blade, the second blade being an ultra-high expansion blade for milling a second casing section. A wellbore system including a borehole in a subsurface formation, two nested casings disposed within the borehole, a string disposed within the casings, a casing mill disposed within or as a part of the string and including a first milling configuration having a first blade for milling a first casing section, and a second milling configuration having a second blade, the second blade being an ultra-high expansion blade for milling a second casing section, the second casing section being radially outwardly disposed of the first casing section, and a stroking tool disposed between the first milling configuration and the second milling configuration.

A mill for a single casing string including a housing, a first blade section having a blade of a first profile disposed in the housing and positionable to axially mill the single casing string, a second blade section having a blade of a second profile disposed in the housing and positionable to axially mill the single casing string, the first and second blades deployable simultaneously, the second blade configured to ride on an inside diameter surface of the single casing string while the second blade in the deployed position.

Disclosed is an apparatus and system, and a method of using the same, comprising An apparatus comprising: a first outer pipe; a central housing attached to the first outer pipe, an annular piston that can impact a brittle barrier, the annular piston comprising an impact surface; a brittle barrier, wherein the brittle barrier is separated from the impact surface by a distance, and wherein the brittle barrier comprises a set of materials; and a second outer pipe attached to the central housing, wherein the central housing is positioned between the first outer pipe and the second outer pipe; wherein the brittle barrier is positioned within one or more of the central housing and the second outer pipe; wherein the annular piston is attached to one or more of the first outer pipe and the central housing via a releasable fastener.

Disclosed is an apparatus and system, and a method of using the same, comprising An apparatus comprising: a first outer pipe; a central housing attached to the first outer pipe, an annular piston that can impact a brittle barrier, the annular piston comprising an impact surface; a brittle barrier, wherein the brittle barrier is separated from the impact surface by a distance, and wherein the brittle barrier comprises a set of materials; and a second outer pipe attached to the central housing, wherein the central housing is positioned between the first outer pipe and the second outer pipe; wherein the brittle barrier is positioned within one or more of the central housing and the second outer pipe; wherein the annular piston is attached to one or more of the first outer pipe and the central housing via a releasable fastener.

A wellbore system includes method of cutting a casing in a wellbore. A string is disposed in the casing, the string including a cutting tool and an activation sub coupled to the cutting tool. The cutting tool includes a ball seat and a cutter. The activation sub includes a control piston disposed therein. The control piston has a ball at an end thereof. The control piston is configured to move within the activation sub to engage the ball to the ball seat when a flow rate of a fluid through the control piston is above a flow rate activation threshold, wherein engaging the ball to the ball seat creates a pressure differential across the ball seat that moves the ball seat to extend the cutter from the cutting tool.

A method to facilitate the extraction of hydrocarbon from a coal seam gas formation is described that includes. : (a) drilling a wellbore using a drill string to access the coal seam gas formation; (b) perforating a section of the drill string; (c) abandoning a section of the drill string in the wellbore; (d) setting a temporary plug to isolate the abandoned section of the drill string and the wellbore; (e) installing a production tubing string above the temporary plug to create a fluid passageway ; (f) displacing a fluid above the temporary plug ; (g) removing the temporary plug to create an initial stimulated reservoir volume and, resultantly, at least partially filling an annulus formed between the abandoned section of the drill string and the wellbore wall with coal fragments; and (h) extracting hydrocarbon from the coal seam gas formation via the fluid passageway to create an expanding stimulated reservoir volume.

An anchor for securing a well tool can include a longitudinally extending central axis, an outwardly extendable grip member, and a mechanical linkage including multiple pivotably connected links. The links pivot relative to each other in a plane laterally offset from the central axis. A method of anchoring a well tool can include flowing a fluid through an anchor connected to the well tool, thereby outwardly extending a grip member into contact with a well surface, and applying a tensile force to the anchor, thereby increasingly biasing the grip member against the well surface and securing the well tool relative to the well surface. A method of anchoring a tubing cutter in a tubular string can include applying a tensile force from an anchor to the tubular string, and cutting the tubular string while the tensile force is applied from the anchor to the tubular string.

An anchor for securing a well tool can include a longitudinally extending central axis, an outwardly extendable grip member, and a mechanical linkage including multiple pivotably connected links. The links pivot relative to each other in a plane laterally offset from the central axis. A method of anchoring a well tool can include flowing a fluid through an anchor connected to the well tool, thereby outwardly extending a grip member into contact with a well surface, and applying a tensile force to the anchor, thereby increasingly biasing the grip member against the well surface and securing the well tool relative to the well surface. A method of anchoring a tubing cutter in a tubular string can include applying a tensile force from an anchor to the tubular string, and cutting the tubular string while the tensile force is applied from the anchor to the tubular string.

A well tool for generating a shaped perforation in a cased wellbore includes a tool body. The told body has at least one wall, a fluid channel, a first perforation device, and a second perforation device. The at least one wall defines an opening and an interior volume. The fluid channel extends from the opening of the at least one wall into the interior volume. The first perforation device is configured to form a perforation tunnel in the cased wellbore disposed in a formation. The second perforation device is coupled to the first perforation device and to the fluid channel. The second perforation device is configured to form the shaped perforation in the formation by flowing fluid received through the fluid channel to the formation through the perforation tunnel.