A seal having a cylindrical body; a plurality of exterior sealing elements disposed on an exterior surface of the body; and a plurality of interior sealing elements disposed on an interior surface of the body, wherein the exterior sealing elements are offset from the interior sealing elements along the body.

A system for cementing a wellbore penetrating an earth formation into which a pipe extends. A cement material is positioned in the space between the wellbore and the pipe by circulated capsules containing the cement material through the pipe into the space between the wellbore and the pipe. The capsules contain the cementing material encapsulated in a shell. The capsules are added to a fluid and the fluid with capsules is circulated through the pipe into the space between the wellbore and the pipe. The shell is breached once the capsules contain the cementing material are in position in the space between the wellbore and the pipe.

A method for abandonment of a subsea well includes: setting a packer of a lower cementing tool against a bore of an inner casing at a location adjacent to an outer casing; fastening a pressure control assembly (PCA) to the subsea wellhead; hanging an upper cementing tool from the PCA and stabbing the upper cementing tool into a polished bore receptacle of the lower cementing tool; perforating a wall of the inner casing below the packer; perforating the inner casing wall above the packer by operating a perforator of the upper cementing tool; and pumping cement slurry followed by a release plug through bores of the cementing tools. The release plug engages and launches a cementing plug from the lower cementing tool. The cementing plug drives the cement slurry through the perforations below the packer and into an inner annulus formed between the inner casing and the outer casing.

A method for abandonment of a subsea well includes: setting a packer of a lower cementing tool against a bore of an inner casing at a location adjacent to an outer casing; fastening a pressure control assembly (PCA) to the subsea wellhead; hanging an upper cementing tool from the PCA and stabbing the upper cementing tool into a polished bore receptacle of the lower cementing tool; perforating a wall of the inner casing below the packer; perforating the inner casing wall above the packer by operating a perforator of the upper cementing tool; and pumping cement slurry followed by a release plug through bores of the cementing tools. The release plug engages and launches a cementing plug from the lower cementing tool. The cementing plug drives the cement slurry through the perforations below the packer and into an inner annulus formed between the inner casing and the outer casing.

Some examples of a packet setting method using disintegrating plug can be implemented as a method for setting a packer in a wellbore. A disintegrating plug is installed in a tubing. The disintegrating plug blocks flow through the tubing in response to pressure. A packer is installed above the disintegrating plug in the tubing. The tubing including the packer and the disintegrating plug is run into a wellbore. The packer is positioned at a wellbore location to create an annular area between the packer and the wellbore wall. Downhole pressure is applied in the tubing to set the packer.

Some examples of a packet setting method using disintegrating plug can be implemented as a method for setting a packer in a wellbore. A disintegrating plug is installed in a tubing. The disintegrating plug blocks flow through the tubing in response to pressure. A packer is installed above the disintegrating plug in the tubing. The tubing including the packer and the disintegrating plug is run into a wellbore. The packer is positioned at a wellbore location to create an annular area between the packer and the wellbore wall. Downhole pressure is applied in the tubing to set the packer.

A wellhead assembly includes a wellhead housing, the wellhead housing including a lock screw receptacle. The wellhead assembly includes an outer nested wellhead component positioned within the wellhead housing, the outer nested wellhead component including a lock screw aperture. The wellhead assembly includes an inner nested wellhead component, the inner nested wellhead component including an inner receptacle. The wellhead assembly includes a nested lock screw. The nested lock screw includes an outer sleeve, the outer sleeve having external threads formed on an outer surface thereof, the outer sleeve threadedly coupled to the lock screw receptacle of the wellhead housing. The nested lock screw includes an inner lock screw, the inner lock screw positioned within and threadedly coupled to the outer sleeve, the inner lock screw passing through the lock screw aperture and engaging the inner receptacle.

An apparatus for drilling a subterranean wellbore using a drill string. The apparatus includes a riser, a sealing device arranged in the riser so as to form a first riser chamber and a second riser chamber, and a riser booster pump. The riser at least partly contains the drill string and defines a substantially annular space around the drill string. The second chamber is in a fluid communication with the riser booster pump so that a kill fluid stored in the second riser chamber may be maintained at a first pressure which is greater than a second pressure of a drilling fluid in the first riser chamber.

An apparatus for drilling a subterranean wellbore using a drill string. The apparatus includes a riser, a sealing device arranged in the riser so as to form a first riser chamber and a second riser chamber, and a riser booster pump. The riser at least partly contains the drill string and defines a substantially annular space around the drill string. The second chamber is in a fluid communication with the riser booster pump so that a kill fluid stored in the second riser chamber may be maintained at a first pressure which is greater than a second pressure of a drilling fluid in the first riser chamber.

A throttling valve formed by introducing an elongate tubular body into a tubular member through which fluid is flowing. The tubular body is provided with first and second ends, the first end being adapted for engaging a flow control device and the second end having a beveled end that enables fluid communication between the tubular member and the tubular body. The tubular body is provided with a tapered stem, the outside diameter of the stem proximate the first end of the tubular body being greater than the outside diameter of the stem proximate the second end, for seating against the opening in the end of the tubular member and effecting a seal between the outside surface of the stem and the margin of the opening in the tubular member. An elastomeric or other seal may be mounted on the outside surface of the stem for this same purpose.