HIGH PRESSURE SWIVEL SYSTEM FOR TURRET-MOORED VESSEL

摘要

A high pressure swivel system provides fluid communication on a turret-moored vessel between a swivel core member being in fixed rotational alignment with a seabed mooring system and a swivel revolving member being in fixed rotational alignment with the hull of the vessel. The revolving member has upper and lower radially extending surfaces. On each of the radially extending surfaces are a series of radially spaced apart pressure seals. Hydraulic barrier fluid pressure is regulated in each of the volumes formed between the pressure seals. The pressures in the volumes are regulated such that a process fluid pressure higher than could be tolerated by any one individual pressure seal is safely accommodated by sharing the high process fluid pressure between or among two or more of the radially spaced apart pressure seals.

主权项

1. A high pressure swivel system for a turret-moored vessel comprising:
a central core member extending axially along a central longitudinal axis, adapted to transfer a high pressure process fluid between a subsea location and the vessel, the core member configured to remain in a fixed rotational alignment with a seabed mooring system; a revolving member having upper and lower revolving member sealing faces extending radially away from the axis, the revolving member having a high pressure fluid port in fluid communication with the process fluid in the core member and configured to revolve about the axis with respect to the core so as to remain in a fixed rotational alignment with a hull of the vessel; upper and lower fixed members each having a fixed sealing face extending radially away from the axis and being configured to remain in fixed rotational alignment with the mooring system; a plurality of upper pressure seals spaced at different radii from the axis, each upper pressure seal configured to form a pressure seal between the fixed sealing face of the upper fixed member and the upper sealing face of the revolving member; a plurality of lower pressure seals spaced at different radii from the axis, each lower pressure seal configured to form a pressure seal between the fixed sealing face of the lower fixed member and the lower sealing face of the revolving member; and a hydraulic barrier fluid supply system configured to supply a pressurized barrier fluid to volumes defined between each of the upper pressure seals and to volumes defined between each of the lower pressure seals such that a pressure of the process fluid is distributed among at least two pressure seals, thereby allowing the pressure of the process fluid to safely exceed operating limits for each of the upper and lower pressure seals.