Abstract: A compressor includes impellers each having its chord angle less than its stall angle. The impellers can be used in a contra-rotating impeller arrangement without static diffusers. The contra-rotating impeller arrangement provides for much larger nominal flow rates than conventional single rotating impeller arrangements with the same chord angles. Accordingly, a surge free design is provided without excessively compromising the nominal flow rate. Techniques for enhancing stall characteristics of the impellers are also described.

Abstract: An electrostatic separator including a separator vessel having an oil collection portion at its upper end, a water collection portion at its lower end, at least one electrode generating an electric field, and an inlet through which an emulsion mixture enters the separator vessel before exposure to the electric field in the upper part of the vessel, wherein the separator vessel further comprises at least one routing blade located proximate to the at least one electrode to route coalesced water droplets downwardly and away from the electric field.

Abstract: A subsea water injection pump includes components that are cooled and lubricated by the process fluid. The pump includes opposing stages of impellers in a “back-to-back” arrangement such that the axial forces of the impeller stages partially or nearly fully offset each other. In some cases, a combination of barrier fluid and process fluid is used for lubrication and cooling.

Abstract: An apparatus includes a seabed-disposed pump that includes an inlet to receive a fluid flow and an outlet. The apparatus includes a liquid retainer that is adapted to receive a fluid flow that is produced by a subsea well. The liquid retainer selectively retains and releases liquid from the fluid flow to regulate a gas volume fraction of the fluid flow that is received at the inlet of the pump.

Abstract: A subsea system includes in-riser equipment, and a surrounding structure configured to be coupled to a marine riser and a subterranean well. The in-riser equipment is positioned within the surrounding structure, and the surrounding structure comprises a power connection extending radially therethrough. The system also includes a power supply located outside of the surrounding structure. The power supply is connected to the in-riser equipment via the power connection through the surrounding structure, to communicate with the in-riser equipment.

Abstract: An apparatus includes a subsea flow line and a two stage heat exchanger. The subsea flow line communicates a process flow that is associated with a subsea well, and the heat exchanger transfers thermal energy between the process flow and an ambient sea. The heat exchanger includes a primary circuit in communication with the flow line to transfer thermal energy with the process flow; and the heat exchanger includes a secondary circuit in thermal communication with the primary circuit to transfer thermal energy with the primary circuit.

Abstract: A fluid system includes a pumping flowline, wherein the pumping flowline is in selectable fluid communication with a production flowline, a cylinder including a first port and a second port, a piston slidably disposed in the cylinder, the piston sealing against an inner surface of the cylinder to form a first chamber and a second chamber, wherein the first chamber is in fluid communication with the first port and the second chamber is in fluid communication with the second port, and a first flowline in fluid communication with the first port of the cylinder and the pumping flowline, the first flowline including a first flowline valve, wherein, in response to opening the first flowline valve, the piston is displaced through the cylinder in a first direction to expand a volume of the first chamber of the cylinder.

Abstract: A technique facilitates coupling of an electrical actuator (20) with a subsea host (22). Effectively, mechanical and electrical connections are both formed during movement of the electrical actuator into engagement with the host. The electrical actuator is moved to a desired host location, and then the electrical actuator is guided into mechanical engagement with the host. During movement of the electrical actuator into mechanical engagement, a drive member (60) and at least one electrical connector (56, 58) of the actuator are operatively coupled with corresponding features of the host, thus enabling engagement of the actuator and host with a simple installation motion.

Abstract: A fluid processing machine that includes a stator capable of generating an electromagnetic field and a first rotor section having at least one impeller and at least one permanent magnet. The stator is configured to electromagnetically engage with the first rotor section so as to rotate the first rotor section about a central axis in a first rotational direction. Further rotor sections can also be included that are induced to rotate in the first rotational direction. Other rotator sections with impellers and permanent magnets can also be included that are driven in a second, contra-rotating, direction by a second stator. Several of the fluid processing machine can be distributed within a surface system or subsea system that transports produced fluid from wells to a surface facility.

Abstract: A vertical multi-bore jumper. The jumper is outfitted with interfaces that include rotatable hubs accommodating perimeter bore terminations that may be rotated about a central production bore. In this manner, the multiple bores may be flexibly aligned with corresponding couplers at equipment located on the seabed. As a result, undue torque is not placed on the jumper in attempting to align multiple bores at the interfaces which may be frequently misaligned at the outset of such installations.

Abstract: A technique facilitates deployment of equipment, e.g. an electric submersible pumping system, in a subsea production operation. According to an embodiment, a subsea tree assembly, e.g. a horizontal subsea tree assembly, comprises a spool body housing having a channel extending therethrough. A production receptacle structure is secured within the channel and provides a reduced internal profile for securing wellbore equipment. For example, the internal profile may be constructed to sealably receive a cable hanger used to support power cable by which an electric submersible pumping system may be suspended. The production receptacle structure also may be equipped with a production stab for interfacing with a tubing hanger located below the production receptacle structure.

Abstract: A controls module for use with a subsea landing string, a blowout preventer (BOP) stack and a lower marine riser package (LMRP) is disclosed. The controls module can be integrated into the BOP stack or the LMRP or between the BOP stack and the LMRP. The controls module includes an input line that is coupled to control the subsea landing string through the BOP or the LMRP. The input line can be a hydraulic line, an electrical line, or a combination.

Abstract: Low frequency power is transmitted over long distances from a surface power supply to a subsea rotating machine, such as a pump or compressor. The low frequency power is used to rotate a motor at low speed. A liquid filled magnetic step-up gear module might be used to increase the low speed motor shaft to a higher speed output shaft that can be used to operate the rotating machine. The magnetic gear module can be configured as a fixed ratio, and the surface power supply can be configured to adjust the power frequency to change the speed of a single subsea rotating machine. In other embodiments, the magnetic gear module can provide a variable gear ratio. A fixed low frequency might be transmitted from the surface and multiple subsea loads can be operated from the same power source, each having their own variable magnetic gear module.

Abstract: A technique which enables construction and operation of a subsea landing string system having a system manifold or manifolds unprotected by a dielectric fluid compensated enclosure. The manifolds contain directional control valves and corresponding solenoids which are able to operate while being exposed to environmental fluids such as seawater. The ability to operate manifolds in an unprotected environment enables the manifolds to be positioned in a variety of locations along the subsea landing string system or in cooperation with the subsea landing string system. The subsea landing string system also may be a modular system in which manifolds are added or removed according to the parameters of a given operation.

Abstract: A technique facilitates continued operation of a position indicator which may be used with a valve or other types of actuatable components. The technique utilizes a housing and a stem driver mounted for rotation within the housing to actuate the valve/component to a desired position. The stem driver has a threaded region which is threadably engaged with a clutch collar located in the housing. When the stem driver is rotated relative to the clutch collar, the clutch collar moves in an axial direction along the interior of the housing. The clutch collar is coupled with a bracket which moves during axial translation of the clutch collar. The clutch collar comprises a flexible portion which enables slippage of threads at the region of coupling between the clutch collar and the stem driver if movement of the bracket becomes sufficiently restricted.

Abstract: A method is provided for determining the flow rate of formation water and/or the total rate of produced water in a gas well. More particularly, a method and system is provided to determine the flow rates of gas, condensate, and water in gas production using a flowmeter.

Abstract: A method for determining flow rate of a multiphase fluid. The method includes measuring a first pressure differential (316) of the multiphase fluid flowing through a rotodynamic pump (310) operating at a rotational speed thereby driving the multiphase fluid, measuring a second pressure differential (326) of the multiphase fluid flowing through a portion (320) of a fluid conduit positioned in series with said rotodynamic pump, and determining, based on the first and second pressure differentials and the rotational speed of said rotodynamic pump, a flow rate of the multiphase fluid.

Abstract: A proximity sensing system is configured to sense proximity of a rotating component in subsea rotating equipment such as pumps, compressors and separators. A plurality of sensing probe modules are included to sense proximity at various locations of the rotating shaft. The probe modules can include a fixed length stinger that can be gas-filled to maintain atmospheric pressure. The probe modules can also be a stinger-less design were the sensor is fixed to an inner pump housing and flexible cable is run through a channel of an outer pump pressure casing to a high pressure penetrator.

Abstract: A subsea pipeline system may include a subsea pipeline station configured to establish fluid communication between a first pipeline and a second pipeline. The first pipeline may have a first diameter, and the second pipeline may have a second diameter different from the first diameter. Additionally, the subsea pipeline station may be configured to removably couple to one or more pig launching assemblies having different configurations.

Abstract: Systems and methods for subsea fluid phase separation. A two phase embodiment of the subsea fluid separation system separates a multiphase flow into gas and liquid phases. A three phase embodiment of the subsea fluid separation system separates multiphase flow into gas, oil, and water phases. The subsea fluid separation systems include a wellhead desander system to remove solids from the multiphase flow, a vertical gas-liquid separation module having associated valves disposed in series with a horizontal gas-liquid separation module having associated valves, one or more pumps to provide fluid flow to the vertical and horizontal separators, and a control system to control operation of the valves and pumps. The three phase embodiment further includes oil-water separators and multi-stage hydrocyclones for produced water treatment in a subsea environment.