A downhole plugging system that includes a setting tool, and adapter, and a downhole tool coupled with the setting tool via the adapter. The setting tool includes a setting tool housing; a tension mandrel; and a setting sleeve coupled with the setting tool housing. The downhole tool includes a slip having a slip body; an outer slip surface; an inner slip surface; and at least two slip segments adjoined by a first portion of slip material at a first slip end, and the two slip segments separated by a slip groove therebetween.

A subsurface tool adapted to extend within a wellbore includes an integrally formed single-component body that defines an external surface and an internal chamber isolated from the external surface. When the tool is subjected to one or more stresses, a stress concentration is created within a stress zone of the single-component body, the stress zone being adjacent the internal chamber.

A system and method for a composite cement retainer. A composite cement retainer has various components. When these various components comprise composite where feasible, or a drillable metal, the retainer can be easily placed and quickly drilled if necessary.

A downhole coupling mechanism for use in downhole tools that find application in wells exploited by a hydraulic refracturing process. The downhole coupling mechanism connects first and second tubular sections via a tensile load arrangement of wires located in complimentary grooves, a torque arrangement of interlocking lugs and notches on opposite ends, and a seal arrangement. The downhole coupling mechanism provides a thin walled coupling where a screw-threaded connection could not achieve the required tensile load, torque and sealing properties needed. Embodiments of a thin walled anchor and packer including the downhole coupling mechanism are described.

A composite downhole tool, such as a frac plug or a bridge plug, having a composite sleeve located around a composite mandrel and defining an overlapping or overlapped section between the two. One or more shear pins with each shear pin having a pin hole is provided with the downhole tool to reinforce the downhole tool from interlaminate shear. The one or more shear pins can further be reinforced from rotation by overlapping at least part of the one or more pins with a lip of a ring.

A transforming bridge-to-flow-through frac plug has a mandrel, a retaining sleeve, a pair of cones, a pair of slips, a packing element, and a keeper ring. The mandrel is concentrically connected within the retaining sleeve, and is constructed of a dissolvable material such that the mandrel is dissolvable through application of a solvent in order to form a big bore flow-through frac plug if removal of the frac plug by milling is not possible. The pair of cones, pair of slips, packing element, and keeper ring are positioned on the exterior of the retaining sleeve in order to secure the frac plug in place after a setting operation, even if the mandrel is dissolved in order to form the big bore flow-through frac plug.

Valve systems and methods for inserting into a casing in a downhole environment are provided. A valve system includes a tool mandrel, a check valve assembly, and a setting system. The setting system includes a sealing element, wedges, slips, and a set nut. Each of the wedges and slips includes an inner surface slidable along the outer surface of the tool mandrel. Each wedge includes a primary angled surface and a secondary angled surface. The wedges are located between the slips and the secondary angled surface of one wedge is in contact to the secondary angled surface of the other wedge. Each of the slips includes an outer surface including gripping elements configured to grip an inner surface of the casing. Also, each of the slips includes an angled side surface configured to engage with the primary angled surface of the wedge.

A subsurface tool adapted to extend within a wellbore includes an integrally formed single-component body that defines an external surface and an internal chamber isolated from the external surface. When the tool is subjected to one or more stresses, a stress concentration is created within a stress zone of the single-component body, the stress zone being adjacent the internal chamber.

A downhole plug for well completion is provided, which rapidly degrades after hydraulic fracturing, so that the flow path is recovered in a short time. A downhole plug (10) is provided, which includes: a mandrel (1) made of a degradable material; and a plurality of peripheral members (2, 3, 4, 5, 6a, 6b, 8a, 8b) made of a degradable material and disposed on an outer peripheral surface of the mandrel (1), where at least one of the plurality of peripheral members (6a, 6b) includes: a hollow portion (64) through which a fluid flowing along an axial direction of the mandrel (1) can pass; or a groove in at least a portion of, a surface serving as an outer surface of the downhole plug (10), or a surface in contact with the mandrel (1).

A backup including a radially inwardly disposed circumferentially continuous ring; a radially outwardly disposed circumferentially discontinuous ring, the circumferentially discontinuous ring comprising a plurality of segments arranged to overlap adjacent ones thereof about a circumference of the circumferentially discontinuous ring.