A down-hole packer is provided for positioning in a wellbore to establish a seal with a surrounding surface. The packer includes a sealing element that is responsive to compression by a setting piston to radially expand into the wellbore. An actuator is provided to longitudinally move the setting piston in response to a telemetry signal received by the down-hole packer. The actuator can include a hydraulic pump, an electromechanical motor or valves operable to control hydraulic energy to apply a down-hole force to the setting piston.

A degradable downhole isolation tool for use in hydrocarbon well completion. The tool sets and isolates zones for fracking, and then degrades without leaving residual parts and without milling or introducing a new degrading fluid. The plug's mandrel and other parts are a solid polymer which hydrolyzes in aqueous downhole fluid to produce an acid which degrades degradable metal slips and other metal parts. The plug's seal may be degradable metal pedals or split rings. The plug is delivered to the well site as an interchangeable parts kit for adaption to the well's requirements.

A downhole tool for sealing a well includes a push ring, a first slip ring located adjacent to the push ring, a first wedge located adjacent to the first slip ring and configured to radially push the first slip ring and separate the first slip ring into individual parts, and a sealing element located adjacent to the first wedge and configured to seal the well. An upstream end of the first slip ring and a downstream end of the push ring form a wavy interface when in contact. The wavy interface locks the first slip ring relative to the push ring to prevent a rotation of the first slip ring relative to the push ring.

A frac plug apparatus has a plug body that comprises a central bore and separable elements. The central bore extends axially through the plug body. The separable elements are joined by relatively weak bridging portions adapted to break in a controlled manner, the separable elements thereby forming an integral component comprised of the separable elements. The separable elements comprise a wedge element and an array of slip elements. The slip elements are joined to the wedge element by first bridging portions.

A slip assembly for a downhole tool, such as a composite plug, has a slip body and at least one insert. The slip body has an incline at one end that interfaces with an inclined surface of a cone. As this occurs, the slip body is pushed away from the tool's mandrel against a surrounding casing wall. The insert is disposed in the slip body with the axis of the insert angled away from the cone. In particular, the insert's axis is preferably angled normal to the slip body's incline and the inclined surface of the cone.

A plug for well drilling comprising a mandrel and members attached on an outer circumferential surface orthogonal to an axial direction of the mandrel, wherein at least one of the members or the mandrel is formed from a degradable material; a ring-shaped ratchet structure formed from a plurality of interlocking parts that allows movement of the member in one direction along the axial direction of the mandrel and restricts movement in the opposite direction is provided on an inner circumferential surface of the member and the outer circumferential surface of the mandrel; preferably further comprising a pushing jig including a ratchet structure and a ring-shaped plate adjacent to the axial direction leading side of the pushing jig. Additionally, a well drilling method using the plug for well drilling, comprising degrading a part or all of the plug after blocking a borehole.

A slip release mechanism provides for undermining the slip cone in the set position of the slips so that the grip of the slips can be released subsequent to allowing the cone ramp to flex. The slips can be pulled back down the cone ramp as the completion of the same motion that undermines the support for the cone.

A technique facilitates plugging of a wellbore during, for example, a fracturing operation. A frac plug is constructed with an unobstructed internal passage and comprises a seal member combined with a plurality of slips for engaging a surrounding wall, e.g. a surrounding wellbore wall. Additionally, the frac plug comprises a lower sub having raised edges arranged to catch a ball during a flow back stage without blocking flow along the unobstructed internal passage.

A method and apparatus for a downhole tool including a slip assembly having a plurality of slips configured to engage a downhole surface. The slip assembly includes a plurality of slip segments. Each slip segment includes a slip body, a plurality of profile elements coupled to the slip body, and a first coating disposed on the plurality of profile elements, wherein the first coating is formed from a plasma electrolytic oxidation treatment. The first coating and the plurality of profile elements form a plurality of gripping elements configured to grip the downhole surface.

An anchor device having a tubular body with a longitudinal axis, the tubular body being divided into a first body portion and a second body portion which are interconnected by means of a rigid connection so that movement between the first body portion and second body portion is substantially prevented, the anchor device further comprising an actuator having an actuation part which, by operation of the actuator, moves relative to the body, wherein the anchor device further comprises a first linkage set and second linkage set each of which includes at least one linkage, each linkage comprising a first, second and third link, the second link lying between the first and third links, and being pivotally connected to both, each linkage further comprising means to releasably pivotally connect the first link to the first body portion, and means to releasably pivotally connect the third link to the actuation part, the first and third links of each linkage in the first set being shorter than the first and third links of each linkage in the second set, and the second link of each linkage in the first set being longer than the second link of each linkage in the second set.