Abstract: An annulus seal system includes a retention plate mounted to a tubing in a wellbore at an uphole longitudinal end of the tubing and an annular isolation system coupled to the retention plate. The annular isolation system includes a bottom holding plate positioned in an annulus between two tubings, a seal element residing on the bottom holding plate to seal the annulus between the tubings, a torque plate, and a top holding plate. The seal element is positioned between the bottom holding plate and the torque plate, and the torque plate moves in a longitudinal direction toward the bottom holding plate to compress the seal element between the bottom holding plate and the torque plate. The top holding plate mounts to the retention plate, and includes an adjustment mechanism engaged with the torque plate to control movement of the torque plate in the longitudinal direction.

Abstract: A method of installing a mechanical barrier in a wellhead includes receiving a false bowl within a bowl of a casing head housing of the wellhead, generating a first sealed interface between the false bowl and the bowl with one or more first seals arranged about an exterior of the false bowl, receiving a plug within the false bowl, generating a second sealed interface between the plug and the false bowl with one or more second seals arranged about an exterior of the plug, and receiving a back-pressure valve within the plug.

Abstract: A wellhead assembly includes a production tree, a sacrificial fluid control assembly, an adaptor assembly, and a sleeve. The sacrificial fluid control assembly is fluidly coupled to the production tree. The adaptor assembly resides between the production tree and the sacrificial fluid control assembly. The adaptor assembly forms, with the adaptor assembly attached to the production tree and the sacrificial fluid control assembly, a common bore. The sleeve is disposed within the common bore and extends from the adaptor assembly to the tubing spool. The sleeve includes i) a first end that forms, with the adaptor or the sacrificial fluid control assembly, a first fluid seal, and ii) a second end opposite the first end and forming, with the tubing spool, a second fluid seal such that the sleeve fluidly isolates a first section of the common bore from a second section of the common bore.

Abstract: A downhole tool includes a top sub-assembly configured to couple to a downhole conveyance operable to move the downhole tool through a wellbore; a housing coupled to the top sub-assembly and including a retention sub-assembly mounted in the housing and a slot formed in a downhole end of the housing and shaped to engage a mudline abandonment cap; and a locking sleeve coupled to the retention sub-assembly and moveable, by the retention sub-assembly, to adjustably lock the slot to the mudline abandonment cap.

Abstract: A downhole tool includes a top sub-assembly configured to couple to a downhole conveyance operable to move the downhole tool through a wellbore; a housing coupled to the top sub-assembly and including a retention sub-assembly mounted in the housing and a slot formed in a downhole end of the housing and shaped to engage a mudline abandonment cap; and a locking sleeve coupled to the retention sub-assembly and moveable, by the retention sub-assembly, to adjustably lock the slot to the mudline abandonment cap.