Abstract: An ocean thermal energy conversion facility includes a long pipe assembly which is supported at its upper end by the hull of the floating facility. Cold water flows to the facility from deep in the ocean. The pipe assembly comprises an elongate pipe construction and a weight connected to the lower end of the construction by a line of selected length. A floatation collar is connected to the construction at its upper end to cause the construction to have positive buoyancy and a center of buoyancy closer to the upper end of the construction than its center of mass. The weight renders the entire pipe assembly negatively buoyant. In the event that support of the pipe assembly should be lost, as by release of the assembly from the facility hull in an emergency, the assembly sinks to the ocean floor where it is moored by the weight. The pipe construction floats submerged above the ocean floor in a substantially vertical attitude which facilitates recovery of the assembly.

Abstract: Apparatus is provided for connecting to a floating structure the upper end of a pipe assembly disposed substantially vertically in an ocean and the like. The pipe can be an upwelling pipe in an ocean thermal energy conversion installation. Gimbal apparatus are coupled between the pipe and the structure concentrically about the pipe. The gimbal apparatus define two orthogonal gimbal axes about which the pipe can move relative to the structure. The gimbal apparatus carry essentially all of the load between the pipe and the structure. Ball joint apparatus are coupled between the upper end of the pipe and the structure to define the boundaries of a path of fluid flow between the pipe and the structure. The ball joint apparatus includes an element associated with the pipe and an element associated with the structure. The ball joint apparatus is centered in the intersection of the gimbal axes.

Abstract: Apparatus is provided for connecting to a floating structure the upper end of a pipe assembly disposed substantially vertically in an ocean or the like. The pipe can be an upwelling pipe in an ocean thermal energy conversion installation. A downwardly open, elongate hollow socket is connected to the structure, and a mating elongate hollow pin member is connected to the upper end of the pipe assembly. Mating of the pin member in the socket requires only upward linear motion of the pin into the socket. Separate tethers are connectible in parallel to the pin and socket between the pipe assembly and the floating structure for holding the pin member in mated engagement with the socket. The tethers are severable for releasing the pipe assembly, which is negatively buoyant, from the floating structure in the event of an emergency or otherwise.

Abstract: An ocean thermal energy conversion facility includes a long pipe assembly which is supported at its upper end by the hull of the floating facility. Cold water flows to the facility from deep in the ocean. The pipe assembly comprises an elongate pipe construction and a weight connected to the lower end of the construction by a line of selected length. A floatation collar is connected to the construction at its upper end to cause the construction to have positive buoyancy and a center of buoyancy closer to the upper end of the construction than its center of mass. The weight renders the entire pipe assembly negatively buoyant. In the event that support of the pipe assembly should be lost, as by release of the assembly from the facility hull in an emergency, the assembly sinks to the ocean floor where it is moored by the weight. The pipe construction floats submerged above the ocean floor in a substantially vertical attitude which facilitates recovery of the assembly.

Abstract: Apparatus for drilling a well at a location submerged below a body of water includes a buoyant foundation structure. The foundation structure is floatable on the surface of the body of water and is subject to vertical motion in response to waves and the like. A riser handling and tensioning mechanism is mounted to the foundation structure and is operable for moving a riser pipe along a substantially vertical line from and to the foundation into and out of connection with the submerged location. The riser handling and tensioning mechanism is also operable for applying tension to a riser pipe connected to the submerged location. The handling and tensioning mechanism includes vertically disposed hydraulic rams mounted to the foundation structure. Holding means are releasably engageable with a riser pipe adjacent its upper end and are connected to the rams for movement along the riser line by the rams.