Abstract: A system for compressing a multi-phase fluid made up of at least one gaseous phase and at least one liquid phase, the system having at least one pair of pumping elements. The system includes an axial-flow pump P1 and a centrifugal pump P2 arranged after the axial-flow pump P1. The two elements are linked by an element which adjusts the fluid from the axial-flow pump to optimize the effect of the centrifugal pump.

Abstract: The present invention relates to a device to compress a multiphase fluid such as petroleum effluent comprising a liquid phase and a gaseous phase and a method to use the device. The device comprises a housing (1), an impeller having an inlet section and an outlet section. The impeller comprises an axisymmetric hub (28) with an axis Ox and a number n of blades rotating around the axis. The blades have a leading edge (C1, C2) and a trailing edge (C'1, C'2). The fluid enters the impeller va the inlet section (41) and leaves via the outlet section (42). The axis is orientated in the direction of advance of the fluid. The number of rotating blades (29, 30) is equal to or greater than 2. At least one channel or passage is defined by two successive blades (29, 30) whose orthoradial section S(x) is of the form, within 5% and preferably within less than 3%:S(x)=ax.sup.2 +b(c-x.sup.2).sup.1/2 +don at least one portion of its length.

Abstract: Device, in particular for regulating and reducing the fluctuations in the composition of a polyphasic flow including at least one liquid phase and one gaseous phase. This device comprises a container for separating said phases and at least one admission opening for the polyphasic mixture, as well as means for extracting the content of the container. The extraction means (3, 7, 40, 41) extend into said container (2, 39, 56) in such a manner that during normal operation, they extend through the liquid-gas interface (6). Said extraction means include extraction openings (4, 16, 19, 50, 51) arranged on both sides of the interface in normal operation; the sum of the throughflow sections of said openings, estimated from a reference position on at least a portion of a vertical axis, varies as a function of the slope, considered on said axis and for said portion, said portion extending during normal operation on both sides of said interface.

Abstract: This invention comprises a device and method for producing and conveying a diphasic fluid. The method comprises mixing the gas with a liquid to produce a diphasic fluid which is forced into a pipe by diphasic fluid pumping means, the amount of the added liquid depending on the maximum value of the gas-to-liquid volumetric ratio of the diphasic fluid which can be processed by the pumping means. A further refinement is achieved by separating a portion of the liquid phase from the pressurized diphasic fluid and recycling it to the mixing stage. The device comprises means for mixing the substantially gaseous fluid with sufficient liquid to form a diphasic fluid having the predetermined gas-to-liquid ratio for the pump. The means for mixing also includes means for equalizing the pressure of the gas and liquid prior to mixing and conveying through the pipe.

Abstract: A two-phase fluid is rotated around a longitudinal axis so as to generate a coaxial flow having a tubular layer (15) formed by the gaseous phase surrounded by a tubular layer (16) formed by the liquid phase. The thicknesses of the tubular layers of the liquid phase and gaseous phase, and the flow velocity of at least the liquid phase (VL) is measured. The flow of each phase can then be determined from empirical data.

Abstract: A method for producing a flow of fluid comprised of at least phases from at least two primary flowing fluids, one of which has at least one liquid phase, and the other at least one gaseous phase, wherein the two primary fluids flow out respectively through one and another orifice, both of which may be streamlined, then a multiphase mixture is produced because the various flows are made to flow out through a third orifice and the channel sections of the orifices are adjusted in such a way so as to regulate at least one of the rate and pressure of the different flows, whereby a homogeneous multiphase flow is produced while minimizing the loss in energy of the different fluids.

Abstract: A feed device for a two-phase fluid pump enabling the pump to be supplied with a two-phase fluid having characteristics, especially the volumetric ratio of the gaseous phase to the liquid phase, compatible with the operating characteristics of the pump. The device has a main pipe (10a) and a plurality of auxiliary pipes (10b, . . . 10i) parallel to the main pipe. Each of the pipes can be connected to an upstream supply line of two-phase fluid, and to the downstream pump (6), each of the pipes having an isolation and flow regulating gate (11a, . . . 11i) at its upstream inlet and an isolation and flow regulating gate (12a, . . . 12i) at its downstream outlet, each of the pipes also having means (16a, . . . 16i; 17a; 17i) for introducing a carrier liquid, such as water.

Abstract: A process for performing a series of hydrodynamic functions or operation on a flow of fluids comprised of at least two phases includes the following steps: separating the fluid phases that comprise the initial flow; reducing the turbulence of the flows of each of the fluid phases which have been separated from each other; and recombining the fluid phases to form a new polyphasic flow with a predetermined structure.

Abstract: A method for ensuring fluid-tightness is applicable to a submersible motor for operation under conditions of total and permanent immersion, especially in oil wells and geothermal boreholes. The emergent end of the drive shaft of the motor is fitted with a rotary packing-gland. The motor casing is filled with oil which is circulated via an axial duct of the drive shaft, the impulse being produced by a disk pierced by radial ducts. A second circuit constituted by a system of ducts including radial ducts comes into contact with the packing-gland which is at overpressure with respect to the external medium. This results in a controlled leakage flow between the two portions of the packing-gland.

Abstract: A motor pump set having two coaxial shafts is provided with a fluid circuit for protecting the rotary packing-gland against any ingress of solid particles such as sand. Pumped fluid is withdrawn from an intermediate space of the pump and returned upstream via a duct within the pump shaft in order to lubricate the bearings as it passes. The fraction of the fluid stream which is discharged from the last bearing flows in the vicinity of the packing-gland and is driven through radial discharge ducts under the action of centrifugal force.

Abstract: A tubular centrifugal separator for immiscible fluids of different specific gravities comprises a tubular body provided with at least one concentric internal partition and fed at one end with the mixture of fluids to be separated. Included are also, at least two separate means for driving the fluid in rotation, the second of which is placed downstream from the end of an internal partition inside the tubular body. Extraction ducts are provided to withdraw the separated fluids and means to feed back remaining fractions of the mixture.

Abstract: A tubular centrifugal separator for immiscible fluids of different specific gravities comprises a tubular body provided with at least one concentric internal partition and fed at one end with the mixture of fluids to be separated. Included are also at least two separate means for driving the fluid in rotation, the second of which is placed downstream from the end of an internal partition inside the tubular body. Extraction ducts are provided to withdraw the separated fluids and means to feed back remaining fractions of the mixture.

Abstract: A mooring station and transfer terminal for offshore hydrocarbon production is provided, comprising a coaxial riser linking underwater production and safety manifolds to surface lines. An underwater connector and quick release means are provided to facilitate rapid connection and disconnection of the riser pipes.

Abstract: This device relates to a pump for diphasic fluids and comprises an impeller having a hub which carries blades of a special design. The intersection of the outer surface of each blade with a cylindrical surface coaxial with the hub is a line whose angle of inclination, relative to a plane perpendicular to the hub axis, has a substantially constant value over about one third of the hub length. Furthermore, the intersection of the inner surface of each blade with said cylindrical surface forms a curve, or profile, which can be divided into four successive portions with different law of variations of the angle of inclination of this profile relative to a plane perpendicular to the hub axis.

Abstract: This invention comprises a device and method for producing and conveying a diphasic fluid. The method comprises mixing the gas with a liquid to produce a diphasic fluid which is forced into a pipe by diphasic fluid pumping means, the amount of the added liquid depending on the maximum value of the gas-to-liquid volumetric ratio of the diphasic fluid which can be processed by the pumping means. A further refinement is achieved by separating a portion of the liquid phase from the pressurized diphasic fluid and recycling it to the mixing stage. The device comprises means for mixing the substantially gaseous fluid with sufficient liquid to form a diphasic fluid having the predetermined gas-to-liquid for the pump. The means for mixing also includes means for equalizing the pressures of the gas and liquid prior to mixing and conveying through the pipe.

Abstract: A method and device for conveying a diphasic fluid of high free gas content through a pipe includes separating a liquid of reduced free gas content from the diphasic fluid. The pressure of the separated liquid and the remaining gas are separately simultaneously increased to the same value and at least some of the increased pressure gas is remixed with the increased pressure liquid to obtain a new fluid of reduced free gas content. This new fluid is then introduced and conveyed through a pipe. Alternatively the steps of the method can be repeated before introducing the new fluid into the pipe for further reducing the free gas content thereof.

Abstract: A mooring station and transfer terminal for offshore hydrocarbon production comprises a watertight caisson topped by a rotatable arm which supports a pipe for loading oil tankers. The caisson houses manifolds and a T F L (Through Flow Line) switching device connected to the different underwater producing wellheads. A T F L - servicing pipe supported by the rotatable arm and connected to the switching device through a rotary coupling at the top of the caisson permits introduction of T F L tools or instruments from the water surface into a selected well through the switching device.

Abstract: An offshore terminal connected to different underwater producing wellheads which comprises an aerial part provided with a rotatable arm which supports a T F L-servicing pipe and two further pipes including a loading pipe for discharging crude into oil tankers.This aerial part is supported via an upright riser by a submerged caisson housing manifolds and a T F L-switching barrel.The riser comprises a plurality of coaxial pipes, which are releasably connected to the top of the caisson by telescopic means, the central conduit of this riser connecting the T F L-servicing pipe to the T F L-switching barrel and the other pipes to different manifolds in the caisson.