Abstract:
Apparatus and method for operating a subsea compression system is disclosed, the subsea compression system comprising a separator (3), a compressor ( 1) and a pump (2), wherein the compressor is operable for compression and discharge of gas that is separated from a well stream fed into the separator, and the pump is operable for pumping liquid that is separated from the well stream. According to the invention, compressed gas is recycled from the compressor discharge side to the compressor intake side via a turbo-expander unit (10) which is drivingly connected to the pump, the pump operable in response to circulation of compressed gas from the compressor discharge side to the compressor intake side.
Abstract:
An electrical gear (1) is disclosed, configured for supply of electrical drive power to a machinery (2) to be rotated at high speed, such as a subsea motor /pump or a subsea motor/ compressor assembly, the electrical gear comprising a high input voltage AC-motor (4) having a low pole number, the AC-motor drivingly connected to a medium output voltage AC-generator (90) having inverted design, wherein in the AC-generator the field windings are supported on a rotor (92) which is journalled for rotation inside an outer stator (91) carrying a high number of magnet poles, the AC- motor is configured to run on high voltage alternating current at a first frequency, and the AC-generator is configured to deliver medium voltage alternating current at a second frequency, higher than said first frequency, to an AC-motor to be energized (3; 30) having a low pole number. A method of operating a subsea machinery at high rotational speed in accordance herewith is likewise disclosed.
Abstract:
A self-burying foundation arrangement is described being arranged to lower itself into the seabed by removal of seabed material, wherein a pressure source is operable to apply suction to effect transport of seabed material via at least one passageway (12) communicating with suction chambers (14) mouthing in a digging end (4) in operation facing the seabed, characterized in that the suction chambers (14) are separated by baffle walls (15), the lower edges (16) of which defines the mouths of a number of suction chambers adjoining each other in array configuration.
Abstract:
An electrical gear (1) is disclosed, configured for supply of electrical drive power to a machinery (2) to be rotated at high speed, such as a subsea motor /pump or a subsea motor/ compressor assembly, the electrical gear comprising a high input voltage AC-motor (4) having a low pole number, the AC-motor drivingly connected to a medium output voltage AC-generator (90) having inverted design, wherein in the AC-generator the field windings are supported on a rotor (92) which is journalled for rotation inside an outer stator (91) carrying a high number of magnet poles, the AC- motor is configured to run on high voltage alternating current at a first frequency, and the AC-generator is configured to deliver medium voltage alternating current at a second frequency, higher than said first frequency, to an AC-motor to be energized (3; 30) having a low pole number. A method of operating a subsea machinery at high rotational speed in accordance herewith is likewise disclosed.
Abstract:
A compensated motor barrier and pump lubrication fluids pressure regulation system for a subsea motor and pump module is disclosed, comprising a hydraulic fluid supply providing barrier fluid and lubrication fluid to the motor and pump module, a barrier fluid circuit (14, 15, 17) in which the hydraulic fluid is pre- tensioned towards the motor by a pressure applied from a first separating pressure compensator (19), a lubrication fluid circuit (21, 22, 24) in which the hydraulic fluid is pre-tensioned towards the pump by a pressure applied from a second separating pressure compensator (26). The second pressure compensator (26) is responsive to the pumped medium pressure at a suction or at a discharge side of the pump and applies the sum of that pressure and its inherent pre-tensioning pressure to the lubrication fluid circuit, and the first pressure compensator (19) is responsive to the pressure in the lubrication fluid circuit and applies the sum of that pressure and its inherent pre-tensioning pressure to the barrier fluid circuit.