Abstract: An apparatus for circulating well fluids in an intervention system is described. The apparatus comprises at least one subsea storage vessel adapted to be located adjacent a subsea intervention system, a first conduit adapted to provide fluid communication between the at least one storage vessel and the intervention system, a second conduit adapted to provide fluid communication between the at least one storage vessel and the intervention system and at least one pump adapted to pump fluid from the at least one storage vessel to the intervention system or from the intervention system to the at least one storage vessel through said first and/or second conduits.

Abstract: A wellbore control device for use in a blow out preventer is described. The control device comprising a housing defining a throughbore, a gate, the gate being movable between a throughbore open position and a throughbore closed position, a first stem attached to the gate and a second stem releasably engageable with the gate, the first and second stems being arranged such that a portion of each stem is exposed to an internal housing pressure and a portion of each stem is exposed to an external housing pressure. When the internal pressure is greater than the external pressure, the pressure differential results in a force being applied to the gate to move the gate to, or retain the gate in, the throughbore closed position.

Abstract: A well containment system is described, the system comprises a blow out preventer, the blow out preventer defining a throughbore and including at least one well containment barrier adapted to seal the throughbore, at least one first seal adapted to seal against the lower end of a riser, and at least one second seal adapted to seal against the upper end of a downhole tubular wherein the at least one first seal is located above the at least one well containment barrier and the at least one second seal is located below the at least one well.

Abstract: A subsea winch is described. The subsea winch comprises a housing adapted to be attached to a well intervention system, the housing having an inlet and an outlet and at least one powered sheave arranged between the inlet and the outlet, the or each powered sheave having a surface adapted to form a frictional engagement with a cable passing between the inlet and the outlet via the at least one sheave. In use, a pull force pulling the cable in a downhole direction applied to the cable by a tool string being lowered into the well intervention system is increased by the winch such that the downhole pull force on the cable at the housing inlet is greater than the downhole pull force at the housing outlet.

Abstract: A tensioning apparatus for applying a substantially constant tension to a workover riser (12) includes a first portion (40) adapted to be coupled to a workover riser, a second portion (44) adapted to be coupled to a marine riser (14) and tensioning means (46) for providing relative movement between the first portion and the second portion to, in use, tension the workover riser.

Abstract: An apparatus (10) for remotely running a subsea production tree (12) and desuspending a well is described. The apparatus comprises a tree running tool (16) adapted to be connected to a production tree, at least one downhole tool, at least one of the tools being a plug retrieval tool (22) and a tool deployment device (18) in hydraulic communication with at least the plug retrieval tool to hydraulically operate the plug retrieval tool.

Abstract: A well intervention system is described which has a riser access drive adapted to be located below a vessel, or a rig, work floor. The riser is tensioned and extends from a subsea wellhead to the access device which, in use, is attached to the riser at the location below the work floor. Embodiments of the invention are described.

Abstract: A control mechanism for use with a safety valve adapted to seal a wellbore is described. The control mechanism comprises at least one valve actuator for engaging with the safety valve, the at least one actuator being moveable, in use, between a valve open position in which the safety valve is open and a valve closed position, in which the safety valve is closed. The control mechanism further comprises biasing apparatus adapted to bias the at least one valve actuator to the valve closed position, wherein, in use, the at least one valve actuator extends from the safety valve up to a wellbore wellhead. In one described embodiment, the safety valve is moved between the open and closed positions by movement of the at least one valve actuator with respect to the wellbore.

Abstract: A blow out preventer (10) includes a housing (40) defining a longitudinal throughbore (16) and a ram cavity (34) and at least one pair of opposed rams (12, 14) located in the ram cavity. Each ram includes a seal (18, 24) disposed on an upper surface (20, 26) and the rams are movable transversely across the bore. The blow out preventer further includes at least one seal seat (30) having a seal surface (36) for engaging with the ram seals. There is a seal seat associated with each at least one pair of rams, the seal seat being moveably mounted in the ram cavity. In one embodiment the seal seat continuously engages the rams as the rams move from a cavity open position to a cavity closed position.

Abstract: A tensioning apparatus for applying a substantially constant tension to a workover riser (12) includes a first portion (40) adapted to be coupled to a workover riser, a second portion (44) adapted to be coupled to a marine riser (14) and tensioning means (46) for providing relative movement between the first portion and the second portion to, in use, tension, the workover riser.

Abstract: A control mechanism for use with a safety valve adapted to seal a wellbore is described. The control mechanism comprises at least one valve actuator for engaging with the safety valve, the at least one actuator being moveable, in use, between a valve open position in which the safety valve is open and a valve closed position, in which the safety valve is closed. The control mechanism further comprises biasing apparatus adapted to bias the at least one valve actuator to the valve closed position, wherein, in use, the at least one valve actuator extends from the safety valve up to a wellbore wellhead. In one described embodiment, the safety valve is moved between the open and closed positions by movement of the at least one valve actuator with respect to the wellbore.

Abstract: A wellbore control device for use in a blow out preventer is described. The control device comprising a housing defining a throughbore, a gate, the gate being movable between a throughbore open position and a throughbore closed position, a first stem attached to the gate and a second stem releasably engageable with the gate, the first and second stems being arranged such that a portion of each stem is exposed to an internal housing pressure and a portion of each stem is exposed to an external housing pressure. When the internal pressure is greater than the external pressure, the pressure differential results in a force being applied to the gate to move the gate to, or retain the gate in, the throughbore closed position.

Abstract: A control mechanism for use with a safety valve adapted to seal a wellbore is described. The control mechanism comprises at least one valve actuator for engaging with the safety valve, the at least one actuator being moveable, in use, between a valve open position in which the safety valve is open and a valve closed position, in which the safety valve is closed. The control mechanism further comprises biasing apparatus adapted to bias the at least one valve actuator to the valve closed position, wherein, in use, the at least one valve actuator extends from the safety valve up to a wellbore wellhead. In one described embodiment, the safety valve is moved between the open and closed positions by movement of the at least one valve actuator with respect to the wellbore.

Abstract: Computer workstation includes a mounting bracket for attachment to a wall, and a cabinet connected to the mounting bracket. A track, attached to the cabinet, is engaged with the mounting bracket to vertically guide the cabinet. A non-contacting sensor detects a computer operator. An input device tray is rotatably connected to the cabinet, and has i) an operating position that holds computer input device(s) in an input position and ii) a stowed position substantially preventing access. First electromagnet selectively retains the tray in the stowed position. Second electromagnet selectively retains the tray in the operating position. An electronic lock control panel accepts authentication input from the operator. An electronic lock control module, in a lockable compartment of the cabinet, is connected to the lock control panel and the sensor. The lock control module separately controls electric current flow through the electromagnets in response to authentication by the lock control module.

Abstract: A ball valve (10) for sealing a conduit (12) is described. The ball valve includes a housing having a throughbore and a valve seat. An apertured ball element (18) is mounted within the housing and is rotatable about an axis of rotation (38) between a throughbore open and a throughbore closed position. The apertured ball element (18) has a first portion (20) and a second portion (22) coupled together which are rotatable and moveable relative to each other. The first portion has a sealing surface for engaging with the valve seat. In use, in the throughbore closed position, the second portion is moveable relative to the first portion to axially displace the first portion from the axis of rotation towards the valve seat such that the sealing surface on the first portion of the apertured ball forms a seal with valve seat.

Abstract: The well bore control valve comprises a housing (12) defining a throughbore (14), the throughbore adapted to receive a first tubular. The valve further comprises first (18) and second gates (20) located within the housing, the gates being movable in different directions transverse to the throughbore between the throughbore open position and the throughbore closed position. Movement of the gates from the throughbore open position to the throughbore closed position, in use, shares a tubular located between the gates. The valve also comprises a first seal seat (22) performing a seal of one of the gates in the throughbore closed position to seal the throughbore. In one embodiment, the gates are axially movable with respect to the throughbore.

Abstract: A tensioning apparatus for applying a substantially constant tension to a workover riser (12) includes a first portion (40) adapted to be coupled to a workover riser, a second portion (44) adapted to be coupled to a marine riser (14) and tensioning means (46) for providing relative movement between the first portion and the second portion to, in use, tension, the workover riser.

Abstract: A completion suspension valve system is described which allows a well to be suspended and desuspended remotely without a dual bore riser to the surface. This is achieved by incorporating a remotely actuatable valve into the production bore of a tubing hanger. The valve is hydraulically operable and may be controlled via the tubing hanger running tool or via the xmas tree. The valve can be closed and tested after the tubing hanger has been installed, thereby isolating the well. The dual bore riser and running tool are retrievable and the MODU type vessel is then free to continue drilling and completion operations elsewhere. The xmas tree can therefore be deployed from a workclass supply boat instead of a MODU type vessel.

Abstract: A bearing mounted ball valve (10) comprises a housing (12) having a throughbore and a valve seat (16) and an apertured ball (18) mounted within the housing in continuous engagement with the valve seat. The apertured ball is rotatable by rotation means (20), about an axis of rotation, between a throughbore open position and a throughbore closed position. The bearing mounted ball valve further comprises bearing means (26) coupled between the apertured ball and the housing for constraining the rotation of the apertured ball about the axis of rotation between the throughbore open and the throughbore closed position. In the throughbore closed position, the bearing means is adapted to release the apertured ball from the axis of rotation to permit the apertured ball to float into a sealing engagement with the valve seat.

Abstract: A lubricator system for receiving the intervention tool string includes a tubular body defining a tubular bore, and the tubular bore having a wall portion defining an aperture with a tool guide disposed in said aperture. A first sleeve surrounds the tubular body and is moveable between a first position where said aperture is covered by the first sleeve and a second position where said aperture is uncovered whereby access is provided to said tubular bore via said aperture. The system also includes a seal to allow the lubricator system to withstand operating pressures when the first sleeve is in the first position.