Aspects of the disclosure relate to convertible float valve assemblies, and associated components thereof, and methods of using convertible float valve assemblies. A convertible float valve assembly may comprise a sleeve, one or more valves and valve bodies coupled to the sleeve, and a collet coupled to the sleeve. A method may comprise lowering the convertible float valve assembly and a ball downhole, seating the ball on the collet, and releasing the sleeve from the one or more valve bodies.

A downhole tool for transmitting rotation to a casing string includes a tool body having a bore extending from a first end to a second end. The downhole tool also includes a cam positioned within the tool body, the cam being axially translatable along an axis of the bore. The downhole tool further includes a recess, formed in an outer diameter of the cam. The downhole tool includes a locking mechanism, positioned at least partially within the tool body. The locking mechanism includes a tool key. The locking mechanism also includes a biasing member, the biasing member driving the tool key toward the retracted position.

A downhole system for multistage fracturing having a first cluster of valves, and a second cluster of valves downhole from the first cluster. Each of the first and second cluster of valves has a frac valve. At least one of the first and the second cluster of valves has a flex valve. A single plugging device is used to open all of the valves in the second cluster, but leaves all valves in the first cluster closed.

Provided, in one aspect, is a ball seat release apparatus. The ball seat release apparatus, according to this embodiment, includes a shear sleeve, and a ball seat body located at least partially within the shear sleeve, a shear feature releasably coupling the ball seat body to the shear sleeve. The ball seat release apparatus according to this aspect further includes a ball seat slidingly engaged within the ball seat body, the ball seat configured to move from a first linear position to a second linear position, and further wherein a locking dog releasably couples the ball seat with the ball seat body.

Apparatus, systems, and methods are used for activating a downhole tool, powered by an exothermic reaction, for operation, while deploying a tubing string from a wellbore surface. The tubing string comprises a coupling for enabling pressurized activation of the downhole tool, which comprises a fuel (e.g., thermite) for producing the exothermic reaction. The coupling enables fluid to flow into an interior of the coupling through a first flow passage, during descent of the downhole tool. A stopper is dropped and/or seated to cause the coupling interior to pressurize to an activation pressure, which causes an activator to activate a burn within the downhole tool. Once the downhole tool completes its operation, the coupling interior is further pressurized to burst a burst disc, which opens a second flow passage for fluid to flow from the interior to exterior of the coupling, while downhole tool and coupling are raised to the surface.

Provided is an downhole actuation mechanism, the actuation mechanism comprising: a first part having a guiding surface; a second part defining a passageway; the second part being movable with respect to the guiding surface between a first position and a second position; the second part defining a first clearance of the passageway in the first position; the second part defining a second clearance of the passageway in the second position, the second clearance being larger than the first clearance.

A frac dart includes a body having an outer surface and an end including at least one opening. A cutter support is mounted at the end adjacent the at least one opening. A cutter is moveably mounted at the cutter support. A counter support is slideably mounted on the outer surface, and a counter is arranged between the counter support and the cutter support. The cutter is operable to sever a portion of the counter.

A plug assembly includes an expandable assembly, a locking ring and a cup. The expandable assembly is adapted to be deformed radially over the locking ring and the cup. The locking ring has a stopping inner surface. The plug assembly is used with one or more untethered objects, the untethered objects having an outer surface adapted to couple with the cup, and the cup having an outer surface adapted to couple with the stopping inner surface of the locking ring. The combination of cup and untethered objects is also adapted to contact an inner surface of the plug assembly and, using well fluid pressure, to apply forces to the plug assembly. The forces cause the longitudinal movement of the cup and untethered objects while contacting the inner surface of the plug assembly until the cup contacts the stopping inner surface of the locking ring.

A hydraulic casing centralizer device includes a cylindrical housing having a central chamber extending through a portion of the cylindrical housing and along a central axis thereof. The hydraulic casing centralizer device includes a locking mechanism that reacts to a hydraulic force when the hydraulic force is applied from an inside of the central chamber. The hydraulic casing centralizer device includes a threaded section that is configured for screwing the device into a casing joint. The threaded section may be disposed in the cylindrical housing.

A technique facilitates reducing or eliminating the risk of premature actuation of a liner hanger system and/or premature release of a miming tool. According to an embodiment, the technique utilizes a running string for deploying a liner hanger assembly having a liner hanger which may be actuated at a desired location to suspend a liner/casing from a surrounding casing string. An anti-preset module may be used in cooperation with the liner hanger to prevent premature actuation of the liner hanger. By way of example, the anti-preset module may use pressure equalization between a region within the miming string and a region between the miming string and the liner hanger to prevent pressure imbalances which could actuate the liner hanger. Additionally, a locking mechanism, e.g. releasable lock dogs, may be used to temporarily lock the liner hanger against premature actuation.