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.

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 apparatus for applying a magnetic pressure to a work piece includes an inductor configured to be disposed in proximity to the work piece and a controller electrically connected to the inductor and configured to control a supply of electrical power in order to output a first voltage over a selected frequency range to determine a frequency that provides a maximum current or a frequency that provides a current within a selected range of the maximum current to the inductor.

An apparatus for applying a magnetic pressure to a work piece includes an inductor configured to be disposed in proximity to the work piece and a controller electrically connected to the inductor and configured to control a supply of electrical power in order to output a first voltage over a selected frequency range to determine a frequency that provides a maximum current or a frequency that provides a current within a selected range of the maximum current to the inductor.

A method of recovering casing from a wellbore in which: a logging tool is run to an estimated stuck point of the casing through the central bore of the casing spear and casing cutter; the casing spear is attached to the casing and tension applied so that logging can be performed over a length at an estimated stuck point both with and without tension to provide the verified stuck point; and the casing cutter is positioned relative to this to cut the free casing; and the spear used to remove it. The method can be performed on a single trip. Embodiments include incorporating a packer to circulate fluid during casing cutting; a disconnect, anchor mechanism and motor to allow use of a motor to operate the cutter; and a Down Hole Power Tool with a method of establishing the required force to recover a length of stuck casing.

A method of recovering casing from a wellbore in which: a logging tool is run to an estimated stuck point of the casing through the central bore of the casing spear and casing cutter; the casing spear is attached to the casing and tension applied so that logging can be performed over a length at an estimated stuck point both with and without tension to provide the verified stuck point; and the casing cutter is positioned relative to this to cut the free casing; and the spear used to remove it. The method can be performed on a single trip. Embodiments include incorporating a packer to circulate fluid during casing cutting; a disconnect, anchor mechanism and motor to allow use of a motor to operate the cutter; and a Down Hole Power Tool with a method of establishing the required force to recover a length of stuck casing.

A system and apparatus for applying and removing weight from a tool string over an installed wireline, including a weight section having a longitudinal slot and a removable closure bar.

A system and apparatus for applying and removing weight from a tool string over an installed wireline, including a weight section having a longitudinal slot and a removable closure bar.

A convertible fishing tool is provided for removing an object (fish) from a wellbore. The fishing tool includes an elongated hollow main housing and a plurality of slip blades that are disposed distal to the main housing and move radially between fully retracted positions and fully extended positions. In the fully retracted positions, the fishing tool is in spear configuration and in the fully extended positions, the fishing tool is in an overshot configuration. The fishing tool also includes an actuation system configured to move the plurality of slip blades in a radial direction between the fully retracted positions and the fully extended positions.

A convertible fishing tool is provided for removing an object (fish) from a wellbore. The fishing tool includes an elongated hollow main housing and a plurality of slip blades that are disposed distal to the main housing and move radially between fully retracted positions and fully extended positions. In the fully retracted positions, the fishing tool is in spear configuration and in the fully extended positions, the fishing tool is in an overshot configuration. The fishing tool also includes an actuation system configured to move the plurality of slip blades in a radial direction between the fully retracted positions and the fully extended positions.