Abstract: An electrically actuated fail-safe valve for controlling fluid flow in deepwater drilling operations comprises a body having a bore therethrough, a closure element mounted in the bore and actuable between a closed position and an open position, a flow tube slidably mounted in the bore, the tube being actuable between a first position in which it does not interfere with the normal bias of the closure and a second position in which it opposes the normal bias of the closure, and a drive mechanism causing the tube to advance from its first to its second position. The drive mechanism comprises a gear drive, a rotating sleeve including a helical groove, and a follower pin on the flow tube and received in the helical groove. Power supplied to the drive causes the sleeve to rotate, bearing on the follower pin and advancing the flow tube to its second position.

Abstract: A subsea actuator for operating a valve (20) or the like comprises a movable wall member (19) fixed to an axially slidable stem and separating a pressure chamber (2) from a space (3) which is subjected to the hydrostatic pressure of ambient seawater. A selector valve (11) is operable to connect the chamber (2) to a source of pressurised fluid, e.g. a source of pressurised gas (14), or to a drain e.g. connected to atmosphere by a pressure vessel (12) and pipe (15). A blowdown valve (16) and dump valve (13) are provided for ejecting liquid collected in the vessel (12). The space (3) may be connected to an open-bottomed container (17) to provide a gas barrier between the seawater and the interior of the actuator. Supply of pressurised gas to the chamber (2) causes the member (19) to be driven forwards, gas being allowed to flow past the member into the space (3) during this movement to assist the expulsion of water from the container (17) and the expulsion of any contaminants from within the actuator.

Abstract: A system for deflecting through-the-flowline ("TFL") tools from a main flowline into a selected branch line comprises a diverter tool which is movable through the main flowline until it locks itself near a selected branch line. The tool is equipped with a diverter head which orients itself in the main flow line such that smooth bore is formed from the main flowline in the branch line.

Abstract: A structure or template forms a tubular support structure for subsea equipment used in drilling and producing offshore oil and/or gas wells. The template contains production manifolding, remote and safety shut-in control, pump-separator, and pipeline connector subsystems. Certain of the structural tubes are segregated to form compartmented ballast chambers capable of being selectively flooded and dewatered. Certain other structural tubes form piling sleeves. The truss or framework of structural tubes include vertical and horizontal tubes, the latter forming circumferential members as well as interstitial supports. The uppermost of the circumferential members or "ring" also functions as a fender to protect the equipment within the template. The template is made negatively buoyant upon launch by flooding the compartmented ballast chambers, keelhauled (swung to a position underneath the keel of the drilling vessel), and then lowered to the subsea floor.

Abstract: A structure or template forms a tubular support structure for subsea equipment used in drilling and producing offshore oil and/or gas wells. The template contains production manifolding, remote and safety shut-in control, pump-separator, and pipeline connector subsystems. Certain of the structural tubes are segregated to form compartmented ballast chambers capable of being selectively flooded and dewatered. Certain other structural tubes form piling sleeves. The truss or framework of structural tubes include vertical and horizontal tubes, the latter forming circumferential members as well as interstitial supports. The uppermost of the circumferential members or "ring" also functions as a fender to protect the equipment within the template. The template is made negatively buoyant upon launch by flooding the compartmented ballast chambers, keelhauled (swung to a position underneath the keel of the drilling vessel), and then lowered to the subsea floor.

Abstract: Apparatus for use in removing paraffin from a well tubing string above a wireline operated subsurface safety valve assembly installed in the tubing string and its method of operation. The safety valve assembly controls the flow of production oil and/or gas fluids through the tubing string. During normal production operations a wireline connects the paraffin cutting apparatus to surface facilities which include apparatus for maintaining sufficient tension on the wireline to hold the safety valve assembly in open position and for releasing tension on the wireline to permit the safety valve assembly to close. The paraffin cutter apparatus contains means for releasably connecting it to the safety valve assembly. Manipulation of the wireline actuates means on the paraffin cutting apparatus to open an equalizer port in the tubing string. Paraffin cut from the tubing string wall is removed by flow of production fluids through the open equalizer port.