Abstract: An anti-rotational joint for connecting sections of cnduits together to form a flowline or the like wherein the joint includes a means that prevents the joint from accidentally unscrewing after it is made up to its desired torque.

Abstract: A riser connector system for securing a marine riser to a marine bottom. The system is comprised of a landing base which is preset on the marine bottom and a connector means which is connected to the lower end of the core of the riser. The landing base has an inverted 45.degree. cone-shaped cover plate which overlies and protects connector heads on the base. The cover plate has openings therethrough in vertical alignment with the connector heads which are normally closed by spring-biased doors to prevent trash from accumulating in the heads. The connector means has an inverted cone-shaped funnel which is adapted to cooperate with the cover plate when assembled and has flowline guidelines therethrough vertically aligned with the openings in the cover plate. A target on the underside of the connector means is viewed by a TV camera positioned on the base to orient the riser during assembly.

Abstract: A subsea flowline connector for remotely connecting and releasing a first flowline such as a peripheral flowline on a marine riser to a complementary second flowline at a submerged location without the use of divers. Further, the seals in the connector may be remotely replaced without the need to bring the connector to the surface. Further, in one embodiment of present invention, a bundle of control/supply lines can be remotely connected to respective submerged lines at the same time as the flowline is connected.

Abstract: A subsea connector system for connecting the lower end of a structural core of a marine riser to a base which has been preset on the marine bottom. The box member of the connector system forms an integral part of a tapered section which, in turn, forms the lower end of the riser. The connector system, in a preferred embodiment, incudes a self-contained source of hydraulic fluid under pressure which actuates the connector to a locked position upon command. The connector also includes a back-up means for remotely locking the connector and three separate means for remotely unlocking the connector.

Abstract: A marine riser system is connected through flowlines and a moonpool plug assembly to a marine vessel. The moonpool plug assembly, when removed from the marine vessel, maintains a fully submerged position due to its having a buoyancy which is less than the net weight of the flowlines to which it is connected.

Abstract: An offshore process vessel is described for connecting service and production hoses to a deepwater production riser system and for performing subsea maintenance thereon without major equipment support. The vessel has a pair of longitudinally aligned moonpools, a derrick above the forward moonpool, a rotary powered turret within the aft moonpool, and tension-maintaining assemblies for terminal hoses in combination with a rotary fluid transfer system for transferring production fluids, electrical power, hydraulic power, and control signals across a rotating interface between the vessel and a flowline bundle of the service and production hoses. The turret supports a coaxially disposed and selectively ejectable plug through which the service and production hoses pass. These hoses are joined together in a linear array along the length of the flowline bundle which hangs as a catenary from the plug while being attached to the riser system.

Abstract: A rotary transfer subsystem is described for transferring production fluids, electrical power, hydraulic power, and control signals across a rotating interface between an offshore process vessel and a flowline bundle of service hoses and high-pressure hoses which are connected to a deepwater production riser system. Tensioning devices are also described for maintaining a selected tension on terminal hoses between the interface and the vessel while the vessel weathervanes during maintenance of position in a watch circle above the riser system. The subsystem and the tensioning devices are mounted on the vessel which is equipped with a powered turret within a circular moonpool and is capable of performing most subsea service functions on the riser system without major equipment support.

Abstract: A marine compliant riser system is provided for attaching a flexible flowline to a buoyed conduit riser section. The improved system includes a yoke assembly for receiving flexible flowline with a means for retaining a terminal portion of the flexible flowline at a substantially normal catenary departure angle. Support means are mounted at the top of the buoyed section, and gooseneck connection means mounted on the support means for establishing fluid communication between the flexible flowline and conduit in the buoyed riser section.An installation method is disclosed for completing the improved riser system in deepwater.

Abstract: A marine compliant riser system connects a subsea hydrocarbon source to a floating surface facility through a lower multi-conduit riser section to a submerged buoy section located below a turbulent water zone and a flexible flowline. Fluid connection is established between corresponding lower riser conduits and the surface facility by a plurality of flexible conduits. Connection assembly means connects individual upwardly-directed flexible conduits with corresponding upwardly-directed lower riser conduits in fluid flow relationship. A yoke assembly mounted on the buoy section, includes beam means for holding a plurality of spaced apart flexible conduit terminations, with each of the flexible conduits being connected individually in catenary arrangement between the yoke assembly and the surface facility. The flexible conduits are attached to the surface facility in compact, non-linear array and to the yoke assembly in substantially linear array.

Abstract: A free-standing, marine production riser and a method of installing same for use in deep-water areas to conduct fluids between the marine bottom and the surface. The riser system is comprised of a lower rigid section and an upper flexible section. The lower rigid section has a casing extending from a preset base on the marine bottom to a point just below the zone of turbulence which exists near the surface of the water. A variable-buoyant buoy having a curved upper surface and a central passage therethrough is mounted on the upper end of the casing to support the casing in a substantially vertical position when the casing is in position on the preset base. A remotely actuated connector assembly is provided on the lower end of the casing for connecting the casing to the preset base. A plurality of conduits are run through the passage in the buoy and through guide means in the casing and are remotely connected to mating conduits on the base.