A mill including a housing having a fluid bypass pathway, a milling feature at a longitudinal end of the housing, a chamber defined by the housing, and a piston disposed in communication with the chamber, the piston defining a fluid passageway initially aligned with the fluid bypass pathway, the piston responsive to pump pressure to move toward the milling feature, the movement misaligning the fluid passageway with the fluid bypass pathway.

The present disclosed technology relates to a downhole tool activation device, and a method of using the device, where the valve is configured to open when the counter device has moved an activation distance in an activation direction, a piston engaged with the counter device, having a wellbore pressure from a fluid source applied to a first side, and a pressure in a fluid reservoir applied to the second side, the piston configured to move a step distance in a first direction when the wellbore pressure exceeds the pressure in the fluid reservoir, and configured to move a step distance in an opposite direction driven solely by a greater pressure in the fluid reservoir than the wellbore pressure, and a flow restrictor in fluid communication with the fluid reservoir and fluid source, configured to restrict the flow of fluid between the fluid source to the fluid reservoir.

A gripper mechanism for a downhole tool is disclosed that includes an eccentric linkage mechanism. In operation, an axial force generated by a power section of the gripper expands the linkage mechanism, which applies a radial force to the interior surface of a wellbore or passage. A sliding portion allows the gripper to slide along a surface of the formation in response to the radial force applied to the interior surface of the wellbore or passage.

A frac dart including an electric counter in the frac dart, an inductor in the frac dart, in electrical communication with the counter, the inductor generating a voltage responsive to the dart moving through a magnetic field. A method for selectively landing a dart on a landing feature in a well including sensing a landing feature by generating an inductor signal with an inductor pursuant to the inductor passing through a magnetic field associated with the landing feature in the well. generating a count in an electrical counter of the dart responsive to the inductor signal, applying a count signal to a switch of the dart based upon the count, selectively passing the count signal to an activator or an actuator of the dart based upon switch position.

A liner hanger running system including a liner hanger having a body including a wall defined by an outer surface and an inner surface. The body includes an opening that extends through the outer surface and the inner surface. A piston housing including a wall portion defined by an outer surface portion and an inner surface portion is spaced from the outer surface of the body to define a piston Chamber exposed to the opening. A piston is arranged in the piston chamber. A liner hanger running tool including a dog key extends into the opening and engages the piston. The dog key is selectively shiftable relative to the liner hanger to release the piston and expose the opening to a setting pressure.

A liner string for a wellbore includes a liner hanger assembly (LHA) and a liner hanger deployment assembly (LHDA) releasably attached to the LHA. The LHDA includes a central bore and a running tool moveable from a locked position to an unlocked position, the running tool including a flow path in communication with the central bore. The liner string further includes a chamber disposed between the LHDA and LHA, wherein the chamber is in selective fluid communication with the flow path. Wherein, when the flow path is closed, the chamber is isolated from the central bore, and when the flow path is open, the flow path provides fluid communication between central bore and chamber.

A braking and setting device is configured to slow down a movement of a tool in a well and to fix the tool relative to the well. The braking and setting device includes two or more arms configured to extend from the tool, toward the well, to brake the movement of the tool along a longitudinal axis X; a movable piston configured to be hosted fully within the tool and to move only when a well fluid acts on a base portion of the movable piston, while a tip portion of the movable piston pushes away the two or more arms; and an actuation mechanism configured to establish a fluid communication between the well fluid and the base portion of the movable piston. The movable piston moves exclusively due to a force exerted by the well fluid on the movable piston.

A thru-tubing recover string (10) and method of moving a stuck object (14) in tubing in a well (16). A bottom hole assembly (22) is connected to a work string and includes a first (32) and a second tool (34), each tool configured to apply a force to the object in order to move the object (14), the first force being an impulse force, the second force being a static force, and the tools being operable independently so that an operator can apply either force in the event that application of one type of force on the object fails to move the object. Embodiments are described for the first tool (32) being a hammer tool or a jar and the second tool being a pulling tool such as a jack. The invention finds application in removing stuck objects such as plugs or actuating elements on tools such as sliding sleeves in production tubing.

A method and apparatus for casing recovery for well abandonment. A string is run-in, the string including a hydraulic jack (18), an anchor (28), a casing spear (20), a downhole flow pulsing device (22) and a pressure drop sub (24). The casing spear grips an upper end of the length of casing to be pulled. The anchor is set in casing of a greater diameter above the length of cut casing. Fluid pumped through the string and through the pressure drop sub will increase fluid pressure at the hydraulic jack to a first fluid pressure (78). Fluid pumped through the downhole flow pulsing device will vary the fluid flow superimposing a cyclic pressure (82) on the first pressure (78), causing oscillation of an inner mandrel (30) of the hydraulic jack. The jack moves the oscillating inner mandrel upwards relative to the anchor to pull the length of casing.

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.