An impression tool for providing an impression of an object in a borehole includes a block held by a gripper. The block has a plurality of discrete elements that can deform or move so as to create an impression of an impacted object. The bock can be formed of knitted wire mesh. The tool is impacted on an object such that an impression is formed in the block.

In certain embodiments, a downhole swivel sub includes a first swivel part configured to connect to a first section of a workstring, and a second swivel part configured to connect to a second section of the workstring. The second swivel part is rotatable relative to the first swivel part. The downhole swivel sub also includes a locking sleeve rotationally coupled with the first swivel part and movable axially between a locking position wherein the first swivel part and the second swivel part are rotationally coupled and an unlocking position wherein the first swivel part is rotatable relative to the second swivel part. The locking sleeve includes at least two first rows of teeth disposed at a same radial position and separated axially on the locking sleeve. The at least two first rows of teeth are configured to engage and disengage with at least two second rows of teeth located on the second swivel part.

A downhole tool for use in a gas or oil well is provided. The tool comprising a length of tubing having at least one annular sealing means mounted on the outer surface thereof. The annular sealing means, which are formed from a eutectic/bismuth based alloy, serve to secure the downhole tool in position within an oil or gas well during so that the tool can carry out its function.

Methods and apparatus for controlling drill string rotation. The apparatus may be a control system for controlling a driver operable to rotate a drill string to form a wellbore extending into a subterranean formation. The control system may include a first controller operable to control rotation of the driver and a second controller communicatively connected with the first controller. During the drilling operations the first and/or second controller may be operable to generate a rotational speed command based on status information indicative of operational status of the drill string, and thereby cause the driver to rotate the drill string based on the rotational speed command

There is provided an axial vibration tool with a flow control element, a rotary motor that provides an actuation force to the flow control element, a first flow path with at least a portion in fluid communication with the rotary motor and providing fluid to drive the rotary motor. A shock tool is carried by the outer housing and generates an oscillating force based on fluid pressure applied to an activation element. A high pressure flow path is between a source of high pressure fluid and the activation element, and a low pressure flow path is between a source of low pressure fluid and the activation element. The low pressure fluid source has a lower pressure than the high pressure fluid source. The flow control element controls flow through at least the high pressure path by applying pressure fluctuations to the activation element when actuated by the rotary motor.

An unbalanced sub-assembly includes a turbine and a shaft coupled to the turbine at a first end of the shaft. The unbalanced sub-assembly is capable of rotating and imparting a vibration to the casing in response to a fluid being passed through the casing. A rupture disc is positioned on one end of the unbalanced sub assembly. The rupture disc is configured to rupture above a specified differential pressure threshold caused by fluid flowing through the vibration assembly. The rupture disc is capable of allowing the fluid to bypass the unbalanced sub assembly when the rupture disc is in a ruptured state. The rupture disc directs fluid through the unbalanced sub assembly when the rupture disc is in an un-ruptured state.

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.

A shock and agitator tool assembly vibrates a drill string to overcome stick slip and other friction-based problems that may occur during directional drilling. The agitator tool portion of the assembly, which can be used without the shock tool, allows for controlled activation and deactivation of the agitator tool by the use of one or more darts pumped downhole. The darts can be retrieved with a wireline tool. When activated, the agitator portion creates alternating pressure pulses. These pulses cause axial movement of the drill string above the agitator. A shock tool is described which utilizes a telescoping mandrel to amplify the axial movement created by the agitator tool.

Systems and methods for fishing a metal object from a subterranean well include a fishing tool with housing, the housing being an elongated member having an internal bore. A first electromagnetic assembly is located within the internal bore of the housing and a second electromagnetic assembly is located at an outer diameter surface of the housing, the second electromagnetic assembly being moveable between a contracted position and an extended position where the second electromagnetic assembly extends outward from the housing. The first electromagnetic assembly is operable to generate a first magnetic force with an adjustable magnitude. The second electromagnetic assembly is operable to generate a second magnetic force with an adjustable magnitude, the first magnetic force and the second magnetic force having a same magnetic polarity.