An offshore well-processing system includes a mobile offshore drilling unit and a remote well-processing device configured to be positioned on an offshore platform different from the mobile offshore drilling unit, the mobile offshore drilling unit defining at least one well center and comprising at least one primary drill rig including at least one drill floor and at least one hoisting system for raising and lowering tubular equipment through the at least one well center from/into a well in the seafloor. The mobile offshore drilling unit and the remote well-processing device are configured to be operationally coupled to each other; and the mobile offshore drilling unit is configured to assist in performing concurrent well-processing tasks on respective wells, including the first well processing task performed by the remote well-processing device on a first well and a second well-processing task concurrently performed by the offshore well-processing system on a second well.

An offshore well-processing system includes a mobile offshore drilling unit and a remote well-processing device configured to be positioned on an offshore platform different from the mobile offshore drilling unit, the mobile offshore drilling unit defining at least one well center and comprising at least one primary drill rig including at least one drill floor and at least one hoisting system for raising and lowering tubular equipment through the at least one well center from/into a well in the seafloor. The mobile offshore drilling unit and the remote well-processing device are configured to be operationally coupled to each other; and the mobile offshore drilling unit is configured to assist in performing concurrent well-processing tasks on respective wells, including the first well processing task performed by the remote well-processing device on a first well and a second well-processing task concurrently performed by the offshore well-processing system on a second well.

A ball valve is provided. The ball valve includes a housing, a ball seat arranged in the housing, a ball member mounted within the housing and being rotatable relative to the ball seat between open and closed positions, the ball seat and ball member defining respective through bores, the ball member including a sealing surface, a bore surface and a leading edge surface extending between the sealing surface and the bore surface, the leading edge surface being configured to cut a body extending at least partially through the valve upon closure of the ball member, wherein said leading edge surface is truncated. The ball member may include a relief region proximate the leading edge surface.

A ball valve is provided. The ball valve includes a housing, a ball seat arranged in the housing, a ball member mounted within the housing and being rotatable relative to the ball seat between open and closed positions, the ball seat and ball member defining respective through bores, the ball member including a sealing surface, a bore surface and a leading edge surface extending between the sealing surface and the bore surface, the leading edge surface being configured to cut a body extending at least partially through the valve upon closure of the ball member, wherein said leading edge surface is truncated. The ball member may include a relief region proximate the leading edge surface.

A method and apparatus for tapping into a pressurized multiple strings of coaxially situated tubulars for wells and/or platforms which have overturned wherein the tapping occurs underwater via a diver or remotely operated vehicle. The assembly includes a tapping tool connectable to the tubular via a saddle connection and an adjustable tapping clamp with adjustable support/locking feet, compression plate with view ports, and angularly adjustable hot tapping system, along with a drill/saw system.

A method and apparatus for tapping into a pressurized multiple strings of coaxially situated tubulars for wells and/or platforms which have overturned wherein the tapping occurs underwater via a diver or remotely operated vehicle. The assembly includes a tapping tool connectable to the tubular via a saddle connection and an adjustable tapping clamp with adjustable support/locking feet, compression plate with view ports, and angularly adjustable hot tapping system, along with a drill/saw system.

In one system, there is an emergency pipe stroker tool, wherein the emergency pipe stroker tool is configured to act as a first mechanical barrier for a well. Further, there is an emergency quick disconnect tool in communication with the emergency pipe stroker tool, wherein the emergency quick disconnect tool comprises a connector assembly and a fluid conduit in communication with the well, and further wherein the connector assembly is configured to simultaneously detach from the well and to seal the well. Further still, there is a cement retainer in communication with the emergency quick disconnect tool and the emergency pipe stroker tool, wherein the cement retainer is configured to act as a second mechanical barrier for the well, wherein, the emergency pipe stroker tool, the emergency quick disconnect tool, and the cement retainer act in coordination to seal a well while establishing the multiple mechanical barriers.

In one system, there is an emergency pipe stroker tool, wherein the emergency pipe stroker tool is configured to act as a first mechanical barrier for a well. Further, there is an emergency quick disconnect tool in communication with the emergency pipe stroker tool, wherein the emergency quick disconnect tool comprises a connector assembly and a fluid conduit in communication with the well, and further wherein the connector assembly is configured to simultaneously detach from the well and to seal the well. Further still, there is a cement retainer in communication with the emergency quick disconnect tool and the emergency pipe stroker tool, wherein the cement retainer is configured to act as a second mechanical barrier for the well, wherein, the emergency pipe stroker tool, the emergency quick disconnect tool, and the cement retainer act in coordination to seal a well while establishing the multiple mechanical barriers.

A wellbore is plugged using a bismuth alloy. The wellbore is arranged so that a liquid bismuth alloy sets with an excess pressure of the plug relative to the borehole fluid pressure along a desired seal height distance.

A wellbore is plugged using a bismuth alloy. The wellbore is arranged so that a liquid bismuth alloy sets with an excess pressure of the plug relative to the borehole fluid pressure along a desired seal height distance.