An apparatus includes a tubular, pressure sensors, expandable pads, a hydraulic chamber, and a computer system. The apparatus can be run in a wellbore. The apparatus is configured to detect whether the tubular is stuck within the wellbore. In response to determining that the tubular is stuck within the wellbore, the apparatus can determine a local of sticking of the tubular in the wellbore and can transmit a signal to the hydraulic chamber to pressurize one or more of the expandable pads, thereby causing the one or more expandable pads to expand and exert a force necessary to free the tubular.

An apparatus includes a tubular, pressure sensors, expandable pads, a hydraulic chamber, and a computer system. The apparatus can be run in a wellbore. The apparatus is configured to detect whether the tubular is stuck within the wellbore. In response to determining that the tubular is stuck within the wellbore, the apparatus can determine a local of sticking of the tubular in the wellbore and can transmit a signal to the hydraulic chamber to pressurize one or more of the expandable pads, thereby causing the one or more expandable pads to expand and exert a force necessary to free the tubular.

An embodiment relates to a composition comprising an amorphous alloy having a low coefficient of friction (COF) of 0.15 or less, wherein the amorphous alloy is substantially free of phosphor (P) and substantially free of boron (B). An embodiment relates to a method comprising solidifying a molten layer of an amorphous feedstock on a preexisting layer by controlling a heating source and a cooling rate so as to avoid formation of crystals in the molten layer and not affect a crystalline structure of the preexisting layer, and forming a specimen; wherein, the at least a portion specimen has the low COF. Another embodiment relates to a system comprising a drill string, wherein the drill string comprises a drilling bit and a drill pipe connected thereto, wherein at least a portion of the drill pipe comprises a coating having the low COF.

A method of recovering casing in a wellbore using a vibratory casing recovery bottom hole assembly. In a vibratory casing recovery bottom hole assembly having a casing spear, a flow modifier and one or more further elements including a shock sub. The flow modifier produces cyclic variations in fluid flow through the assembly at a first frequency and at least one of the elements is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. By tuning elements of the bottom hole assembly to be close or at the frequency of the output of the flow modifier, the dynamic amplification factor of the system is maximised and longer lengths of casing can be recovered. A method of recovering casing using the vibratory casing recovery bottom hole assembly is also described. Further embodiments include a casing cutter and a hydraulic jack.

A vibratory casing recovery bottom hole assembly and a method of recovering casing in a wellbore. The vibratory casing recovery bottom hole assembly includes a casing spear, a flow modifier and a dynamic amplification tool. The flow modifier produces cyclic variations in fluid pressure through the assembly at a first frequency and the bottom hole assembly is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. The dynamic amplification tool induces vibration in the bottom hole assembly while ensuring the dynamic amplification factor of the system is greater than one so as to transmit maximum vibration to the casing at the casing spear. Embodiments of dynamic amplification tools are described.

A welding tool consisting of a tubular body having a lateral end and a pin end. The pin end has external threads disposed around an external circumferential surface of the pin end. The lateral end comprises an inner wall defining an orifice. Additionally, a heat proof shell is disposed circumferentially around the lateral end. The welding tool further includes a battery housing. The battery housing encloses a plurality of batteries which store energy. The welding tool further includes a welding element disposed on an inner surface of the orifice and an electric line. The electric line is coiled within the tubular body and physically contacts the welding element and is electrically connected to the plurality of batteries. The welding tool further includes a controller. The controller is capable of receiving and parsing mud pulse signals and controlling the release of stored energy from the batteries to the electric line.

A junk crusher device for crushing junk in a fluid stream includes a circular plate and a shaft. The circular plate includes fluid stream discharge holes and a bearing. The shaft is disposed within the bearing and includes detachably connected tear blades that are configured to rotate with the shaft. The junk crusher device further includes an impeller, hydraulically driven by the fluid stream, configured to rotate the shaft, an internal housing including fixed blades, and a body configured to receive the internal housing such that the internal housing is secured to an interior of the body. The rotating tear blades and fixed blades are configured to crush junk in the fluid stream. The fluid stream discharge holes disposed in the circular plate are configured to filter crushed junk.

An agitator deployable in a wellbore includes a housing including a central axis and a central passage, a valve including a first valve body having a first contact face and a second valve body permitted to rotate relative to the first valve body and having a second contact face configured to contact the first contact face, a first valve adapter including a first receptacle which receives at least a portion of the first valve body to couple the first valve adapter to the first valve body, and a flexible valve configured to permit the first valve body to flex relative to the first valve adapter whereby an angular misalignment may form between a central axis of the first valve body and a central axis of the first valve adapter.

A method and apparatus for single-trip casing cutting and pulling for well abandonment and slot recovery. Perforations (28) are made in the casing (12) at a maximum depth using a punch tool (18) and fluid circulated through the perforations to determine a return at surface. In the event of a return at surface being detected, the casing (12) is cut and pulled. When no return is detected, perforations are made at increasingly shallower depths until a return is detected and the casing (12) is then cut and pulled. This ensures the maximum length of casing (12) is cut and pulled on a single trip in the well bore (10).

A diffuser assembly is provided, comprising a diffuser adapted to reside within a conduit, having an upper member mountable within the conduit and having a fluid inlet port, and a lower section having a diffuser screen; a plurality of stationary diffusing members below the fluid inlet port, wherein the diffusing members are radially oriented relative to a central axis of the diffuser; and (c) a centralizing member above the diffuser screen having a diameter greater than the diffuser screen. The diffuser screen is a cylinder having a plurality of diffuser slots formed therein and a bottom cap having a fluid port; and each of the plurality of diffusing members extends substantially parallel to the central axis.