A mechanical jar including a housing, a piston disposed in the housing and responsive to applied fluid pressure to move in a first direction relative to the housing, a biasing arrangement disposed in the housing and configured to bias the piston in a second direction opposite the first direction, and a restraint configured to prevent movement of the piston in the second direction until a threshold force is applied to the restraint by the piston, whereafter the piston suddenly moves in the second direction.

One method includes temporarily sealing and isolating a portion of a wellbore with a reusable sealing and isolation element, performing a fracturing process in the portion of the wellbore that is isolated, and after the fracturing process is complete, unsealing or de-isolating the portion of the wellbore by temporarily changing a configuration of the reusable sealing and isolation element. Use of the reusable sealing and isolation element may reduce, or eliminate, the need for remediation operations, such as the removal of sealing plugs.

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.

The present invention relates to a downhole self-propelling wireline tool string for being connected to and powered by a wireline for propelling a tool forward in a well and/or for providing weight on a bit while performing an operation, comprising a first downhole self-propelling wireline tool, comprising a first tool body, a first electric motor operating at a rotational speed, a first electric control unit for controlling the rotational speed of the electric motor, one first drive section, comprising a plurality of projectable arm assemblies movably connected at a first arm end with the tool body and projectable from the tool body by means of a first fluid having a first fluid pressure, and a plurality of wheels for contacting a wall of the well, each wheel comprising a hydraulic motor for rotation of the wheel to provide a self-propelling movement, and each wheel being connected with a second arm end of one of the arm assemblies, a first hydraulic pump driven by the electric motor for generation of a second fluid pressure for driving the hydraulic motor(s) rotating the wheel(s), and wherein the downhole self-propelling wireline tool string further comprises a second downhole self-propelling wireline tool, comprising a second tool body, a second electric motor operating at a rotational speed, a second electric control unit for controlling the rotational speed of the electric motor, one second drive section comprising a plurality of projectable arm assemblies movably connected at a first arm end with the tool body and projectable from the tool body by means of a first fluid having a third fluid pressure, and a plurality of wheels for contacting the wall of the well, each wheel comprising a hydraulic motor for rotation of the wheel, and each wheel being connected with a second arm end of one of the arm assemblies, at least one second hydraulic pump driven by the second electric motor for generation of a fourth fluid pressure for driving the hydraulic motor(s) rotating the wheel(s), and wherein each electric motor comprises a power-limiting unit in order to distribute a first part of the current from the wireline to power the first electric motor and a second part of the current to power the second electric motor.

The present invention relates to a method for controlling a tool string having a downhole self-propelling wireline tool having wheels rotated by means of hydraulics and connected to projectable arm assemblies projected by hydraulics, comprising running a downhole self-propelling wireline tool into a wellbore, the downhole self-propelling wireline tool being connected to a second end of a wireline, and a first end of the wireline being connected to a power supply, the downhole self-propelling wireline tool having a tool body and a plurality of wheels rotated by means of hydraulics, and each wheel being connected to a projectable arm assembly projectable from the tool body by means of hydraulic fluid from a first hydraulic pump, the downhole self-propelling wireline tool having an electric motor rotating at an operational rotational speed for driving the first pump; supplying electric power to the downhole self-propelling wireline tool to operate the downhole self-propelling wireline tool at a first speed to urge the downhole self-propelling wireline tool through the wellbore at a first force; determining a motor output torque of the electric motor; determining a maximum allowable motor rotational speed based on the motor output torque; and comparing the operational rotational speed with the maximum allowable motor rotational speed, wherein the method further comprises adjusting the operational rotational speed of the electric motor based on the comparison in order to adjust the first speed to a second speed if the operational rotational speed is higher than the maximum allowable motor rotational speed. The invention also relates to a hydraulically driven downhole self-propelling wireline tool configured to perform the method.

An electric submersible pump (ESP) assembly. The ESP assembly comprises an electric motor; a seal section; a fluid intake; a charge pump assembly located downstream of the fluid intake and having an inlet in fluid communication with an outlet of the fluid intake, having a fluid mover coupled to a drive shaft, and having a fluid reservoir located downstream of the fluid mover; a gas separator located downstream of the charge pump assembly and having an inlet in fluid communication with an outlet of the charge pump assembly; an inverted shroud coupled at an upper end to the gas separator or to the charge pump assembly and coupled at a lower end to the ESP assembly below the fluid intake; and a production pump assembly located downstream of the gas separator and having an inlet in fluid communication with a liquid phase discharge port of the gas separator.

A tool assembly, a method and a system to be used in a downhole environment for downhole operations such as runs and retrieval of features are disclosed. A tool assembly include an outer tool profile, an inner matching profile, and a first interfacing surface. The inner matching profile is to be associated with an interfacing profile of a tool body and is to allow axial sliding for a first lock of the tool assembly to the tool body. A second lock is provided at a first shoulder-surface interface between the first interfacing surface and the tool body. The tool assembly is to be changeably associated with the tool body for use in the downhole operations.

A tool assembly, a method and a system to be used in a downhole environment for downhole operations such as runs and retrieval of features are disclosed. A tool assembly include an outer tool profile, an inner matching profile, and a first interfacing surface. The inner matching profile is to be associated with an interfacing profile of a tool body and is to allow axial sliding for a first lock of the tool assembly to the tool body. A second lock is provided at a first shoulder-surface interface between the first interfacing surface and the tool body. The tool assembly is to be changeably associated with the tool body for use in the downhole operations.

Disclosed is a pipeline pulling tool having an elongate housing. First and second roller wheel sections have at least two freely rotating roller wheels extending out from a sidewall of the housing. An attachment for a tool string is fixed to one of the roller wheel sections. A main section with a retractable propulsion wheel and at least one actuator for actuating the propulsion wheel between an extended position, out from the sidewall of the housing, and a retracted position, inside the housing, is located between the first roller wheel section and the second roller wheel section. A method of actuating a pipeline pulling tool is also disclosed.