Abstract: A constant motion pipe swivel joint having a greatly improved useful life without leakage of fluid from the joint. The swivel joint includes a plurality of sealing discs rotatably positioned between an outer joint member and an inner joint member. One side of each disc is coated with a material having a low coefficient of friction and the other side of each disc is bonded to a layer of elastomeric material such as rubber. The discs are pressed together by the inner and outer members to provide a seal which prevents leakage of fluid from the joint. The rubber stretches to allow small degrees of rotation of the joint without any slippage of one disc over another, and the surfaces of the discs are free to slip over each other to allow a large amount of rotation of the outer joint member relative to the inner joint member.

Abstract: Method and apparatus for hydraulically controlling subsea well equipment, such as valve operators, connectors, and other hydraulically actuated devices, with a significantly reduced number of hydraulic pressure source lines from the surface to the subsea location of said well equipment. The apparatus includes a multi-mode subsea switching valve having a plurality of module-like sections, each section having an inlet port, a vent port and a plurality of outlet ports. When installed, this valve preferably is located near the subsea well, and a source of hydraulic pressure and a plurality of hydraulic switches, all located on a surface vessel or other surface facility, are connected to the valve's inlet ports by means of a relatively small number of hydraulic pressure source lines. A relatively large number of hydraulic outlet lines interconnect the valve's outlet ports and the subsea well equipment so that in each of its functional modes the valve directs fluid pressure to a different set of subsea devices.

Abstract: Method and apparatus for hydraulically controlling subsea well equipment, such as valve operators, connectors, and other hydraulically actuated devices, with a significantly reduced number of hydraulic pressure source lines from the surface to the subsea location of said well equipment. The apparatus includes a multi-mode subsea switching valve having a plurality of module-like sections, each section having an inlet port, a vent port and a plurality of outlet ports. When installed, this valve preferably is located near the subsea well, and a source of hydraulic pressure and a plurality of hydraulic switches, all located on a surface vessel or other surface facility, are connected to the valve's inlet ports by means of a relatively small number of hydraulic pressure source lines. A relatively large number of hydraulic outlet lines interconnect the valve's outlet ports and the subsea well equipment so that in each of its functional modes the valve directs fluid pressure to a different set of subsea devices.

Abstract: Method and apparatus for hydraulically controlling subsea well equipment, such as valve operators, connectors, and other hydraulically actuated devices, with a significantly reduced number of hydraulic pressure source lines from the surface to the subsea location of said well equipment. The apparatus includes a multi-mode subsea switching valve having a plurality of module-like sections, each section having an inlet port, a vent port and a plurality of outlet ports. When installed, this valve preferably is located near the subsea well, and a source of hydraulic pressure and a plurality of hydraulic switches, all located on a surface vessel or other surface facility, are connected to the valve's inlet ports by means of a relatively small number of hydraulic pressure source lines. A relatively large number of hydraulic outlet lines interconnect the valve's outlet ports and the subsea well equipment so that in each of its functional modes the valve directs fluid pressure to a different set of subsea devices.

Abstract: A subsea riser system for conducting petroleum or other fluid from the ocean floor to a floating loading and storage terminal or other facility at the water surface. The bottom end of the riser is connected to a subsea base by a hydraulic connector, and the lower portion of the riser is supported in tension between the subsea base and a submerged tension leg platform. The portion of the riser between the submerged platform and the floating terminal is flexible to accommodate relative movement between the platform and terminal, this flexibility accomplished by means of a series of pipe swivel joints spaced along the riser.