A tubing rotator and a drive therefor. The tubing rotator includes an input shaft to a tubing rotator gear; an electric motor including an output shaft; and a plurality of worm drives arranged in series and configured to (i) receive input from the electric motor and (ii) output torque to the input shaft of the tubing rotator. The worm drives may be identical speed reducers, such as with an input to output reduction ratio of from 25:1 to 40:1.

A system that includes a hanger orientation system that orients a tubing hanger within a wellhead. The hanger orientation system includes a conduit defining a first end and a second end opposite the first end. A sleeve couples to the conduit. The sleeve defines a spiral groove that engages a pin to rotate the tubing hanger.

One illustrative apparatus (1) disclosed herein includes a helix structure (20) that comprises at least one helical surface (15), a plurality of orientation slots (17) positioned around a perimeter of the helix structure, each of the orientation slots (17) being adapted to receive an orientation key (18), a component orientation slot (21) positioned adjacent a bottom end of the at least one helical surface (15) and a threaded bottom recess (43). The apparatus (1) also includes a threaded adjustable nut (30) that is adapted to be at least partially positioned in the bottom recess and threadingly coupled to the threaded bottom recess (43).

A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

A wellhead assembly that includes a wellhead disposed at a surface of a wellbore, a production tree fluidically coupled to the wellhead, and a telescopic adaptor assembly residing between and fluidically coupled to the wellhead and the production tree. The telescopic adaptor assembly extends or retracts to change an elevation of the production tree with respect to the wellhead and rotates to change a radial position of the production tree with respect to the wellhead. The telescopic adaptor assembly includes a flange attached to the wellhead and a first pipe rotationally coupled to the flange. The first pipe is rotational about a longitudinal axis of the first pipe. The telescopic adaptor assembly includes a second pipe attached to the production tree and is disposed concentrically inside the first pipe. The second pipe is movable along the longitudinal axis with respect to the first pipe.

A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

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 wellhead assembly that includes a wellhead disposed at a surface of a wellbore, a production tree fluidically coupled to the wellhead, and a telescopic adaptor assembly residing between and fluidically coupled to the wellhead and the production tree. The telescopic adaptor assembly extends or retracts to change an elevation of the production tree with respect to the wellhead and rotates to change a radial position of the production tree with respect to the wellhead. The telescopic adaptor assembly includes a flange attached to the wellhead and a first pipe rotationally coupled to the flange. The first pipe is rotational about a longitudinal axis of the first pipe. The telescopic adaptor assembly includes a second pipe attached to the production tree and is disposed concentrically inside the first pipe. The second pipe is movable along the longitudinal axis with respect to the first pipe.