A well tool can include an annular seal and a radial expansion mechanism having radially retracted and radially expanded configurations, the annular seal being longitudinally displaceable relative to the radial expansion mechanism in the radially retracted configuration. A method of setting a well tool can include positioning the well tool in a well, the well tool including an annular seal and a radial expansion mechanism, and then longitudinally displacing the annular seal to a radially outward position relative to the radial expansion mechanism. A well system can include a well tool including an annular seal, a radial expansion mechanism, an inner mandrel assembly and a setting sleeve, and a setting tool that produces a relative longitudinal displacement between the setting sleeve and the inner mandrel assembly, the annular seal radially outwardly overlying the radial expansion mechanism in response to the relative longitudinal displacement.

A composite circular connector seal, or an assembly comprising a plurality of such seals, may be engineered to seal across a predetermined tolerance band for such seals by using two substantially circular seal elements sized to slidingly fit about a tubular that has a positive and negative outer diameter tolerance range, where each seal element is terminated at one circumferential edge with a packer cap, and a core element disposed intermediate the two substantially circular seal elements at their respective non-packer cap terminated circumferential edges. The two substantially circular seal elements comprise an organic thermoplastic polymer and the core seal element, which typically comprises a synthetic rubber, is also typically molded to the two seal elements at their respective non-packer cap terminated circumferential edges.

A pressure control device may include a body having a central axis extending therefrom; at least one rotatable seal within the body, the rotatable seal configured to seal against a tubular extending through the pressure control device along the central axis and rotate within the body with the tubular; at least one coil within the body wrapped at least once around the central axis, wherein the at least one coil is configured to send characteristics of the tubular to a controller; an outlet to divert fluid from an annulus, wherein the outlet being located axially below the at least one rotatable seal, wherein the controller is configured to control the at least one rotatable seal and its engagement against the tubular based on the characteristics of the tubular received by the controller.

A pressure-energized ring joint gasket such as a CX gasket for a clamp or other connector includes a cylindrical inner surface oriented toward adjacent sections of a subsea stack that are to be joined by the connector, wings that taper away from the cylindrical inner surface and end in a rectangular shoulder, wherein a portion of the rectangular shoulder is removed to create a boss, an upper groove, and a lower groove, and D-rings in the upper and lower grooves. The gasket can be used to connect adjacent sections of the stack and to maintain a seal between the sections whether the external sea water pressure is greater or less than the internal well pressure. A method for using the gasket for connecting adjacent sections of a subsea stack in offshore drilling environments is also provided.

A well tool can include an annular seal and a radial expansion mechanism having radially retracted and radially expanded configurations, the annular seal being longitudinally displaceable relative to the radial expansion mechanism in the radially retracted configuration. A method of setting a well tool can include positioning the well tool in a well, the well tool including an annular seal and a radial expansion mechanism, and then longitudinally displacing the annular seal to a radially outward position relative to the radial expansion mechanism. A well system can include a well tool including an annular seal, a radial expansion mechanism, an inner mandrel assembly and a setting sleeve, and a setting tool that produces a relative longitudinal displacement between the setting sleeve and the inner mandrel assembly, the annular seal radially outwardly overlying the radial expansion mechanism in response to the relative longitudinal displacement.

Sealing assemblies with rolling annular seals are provided. In one embodiment, an apparatus includes a stuffing box having a rolling seal positioned in a body for sealing against a tubing or wireline cable received in a bore of the body. The rolling seal can rotate within the body to roll along the tubing or wireline cable in response to movement of the tubing or wireline cable through the body and friction between the rolling seal and the tubing or wireline cable. Additional systems, devices, and methods are also disclosed.

A metal to metal seal and method including a first sealing member and a second sealing member, wherein the first and second sealing members are attached together to form a cylindrical sealing device; a first sealing surface and a second sealing surface on the first sealing member and the second sealing member, wherein the first and second metal sealing surfaces form a metal to metal seal with an internal cylindrical sealing surface and an external cylindrical sealing surface respectively; a transverse facing recess positioned between the first and second metal sealing surfaces; a nonmetal seal received in the transverse facing recess; and at least one pressure communication hole on each of the first and second sealing members, wherein the nonmetal seal is in fluid communication with the pressure communication holes, and a pressure differential across the sealing device energizes the nonmetal seal.

Compositions and methods are beneficial for use in downhole applications, especially oil and gas well bores. A composition includes an elastomer doped with a dopant. The presence of the dopant increases a rate of microbial degradation of the elastomer by a microbe. A method includes forming an article including a doped polymer. The doped polymer includes an elastomer doped with a dopant. The method also includes placing the article in a service environment. The presence of the dopant in the doped polymer increases a rate of microbial degradation of the elastomer by a microbe in the service environment.

This disclosure provides a completion tool that uses a rolling seal to actuate a flow valve or replace a piston in a down hole tool. The rolling seal is located in a fluid chamber of the completion tool and divides the fluid chamber into first and second smaller fluid chambers and fluidly seals the first smaller fluid chamber from the second smaller fluid chamber. The rolling seal responds to a fluid pressure within the fluid chamber that causes the closed end of the rolling seal to invert thereby transferring fluid pressure between the first and second fluid chambers, which actuates a flow valve actuation assembly.

A drill piping or tubing pressure seal includes a diameter-spanning body portion. The diameter-spanning body portion includes a high-pressure side, a low-pressure side and a plug receptacle passing through the diameter-spanning body portion from the high-pressure side to the low-pressure side. The high-pressure side and the low-pressure side of the diameter-spanning body portion include a protective coating; however, an interior surface of the plug receptacle located between the high-pressure side and the low-pressure side does not include the protective coating. In addition, a plug is configured to be located within the plug receptacle, and the plug is configured to be retained within the plug receptacle by an anchor element to maintain the plug within the plug receptacle until a breakaway force of the anchor element is exceeded. A gasket is located between a portion of the plug and the plug receptacle.