Abstract: A technique is provided for pumping fluid in subsea applications. A self-contained pumping module is created by mounting a pumping unit on a skid that can be lowered to a sea floor. The skid comprises a support structure designed to hold the pumping unit in a desired orientation, such as an inclined orientation with respect to a base of the skid. The self-contained nature of the pumping module facilitates deployment to a sea floor/retrieval from the sea floor to enable use of the pumping module in a variety of subsea applications with reduced complexity and cost.

Abstract: An electric submersible pump (“ESP”) module is disclosed for producing fluids from subsea wells. The ESP module includes at least two ESPs positioned side by side and connected in parallel to discharge into a common manifold. The ESPs and manifold can be enclosed in a housing and deployed to a subsea location. At the subsea location, the ESP module can be operationally connected to an electric source, the production fluid, and to an export conduit. The production fluid from the well(s) is drawn from within the housing into one or more of the at least two ESPs which energize and discharge the production fluid into the manifold and through the export conduit to a collection point. Each of the ESPs may be selectively operated to provide the desired flow rate and/or lifting head.

Abstract: A pump system for producing fluids from a reservoir using a wellbore having a vertical section with a casing defining an annulus, a transitional section and a horizontal section, and a production tubing having a vertical section and a horizontal section, wherein the system includes a completion with an isolation device in the annulus near the bottom of the vertical section, a gas/liquid separator for receiving produced fluids from the horizontal section, and a vertical lift pump; a continuous flow path from the terminus of the production tubing to the vertical section; a plurality of horizontal pumps in the horizontal section, each having an intake exposed to the reservoir and an outlet in the continuous flow path. The horizontal length of the production tubing is closed to the reservoir except through the horizontal pumps.

Abstract: A basin for use in liquid handling, such as sewage handling. The basin is comprised of a bottom wall, a side wall, and an open top, and a hanging feature formed in the body of the basin. A basin assembly for liquid handling may include the basin, and a hanging member suspended from the hanging feature within the basin. One or more level switches may be attached to the hanging member. A sewage handling system may include the basin assembly, a top cover fastenable to the open top of the basin, and a pump disposed in the basin.

Abstract: An apparatus, system and method for sealing an electrical submersible pump assembly are described. An electric submersible pump (ESP) system for pumping solid-laden fluid comprises a thrust chamber of an ESP seal section, the thrust chamber sealed from well fluid on a downstream side by a stationary sand barrier and on an upstream side by a mechanical seal, the thrust chamber further comprising, a rotatable shaft extending axially through the thrust chamber, a head tubularly encasing the thrust chamber and threadedly coupled to a centrifugal pump intake, and a diamond-coated hydrodynamic bearing set inside the thrust chamber, wherein well fluid enters and exits the chamber through cross-drilled apertures in the head of the chamber, and wherein the well fluid forms a hydrodynamic film between the bearing set.

Abstract: This invention relates generally to a high volume, buoyancy controlled submersible pump assembly designed to sit on the bottom of a body of water or other liquid substance and move a large volume of water or liquid substance. Alternatively, the submersible pump assembly is capable of achieving and maintaining neutral buoyancy or near neutral buoyancy in a particular body of water or liquid substance. The neutrally buoyant version includes maintaining the pump assembly at a given depth without requiring it to sit on the bottom of the body of water or other liquid substance. This invention also relates to linear electrofusion for thermoplastic components.

Abstract: An electric submersible pump device having a motor part, a pump part, and a protector part. The protector part includes redundant shaft seal parts.

Abstract: A pump is provided featuring a housing and battery configuration, where the housing is configured with a battery receiving portion having electrical terminals for receiving power to the pump, and where the battery has a protruding portion with corresponding electrical terminals configured to contact the electrical terminals to provide power to the pump when the protruding portion of the battery is inserted into the battery receiving portion of the housing and rotated in one direction to an “ON” position, and also configured not to contact the electrical terminals when the battery is not rotated to the “ON” position.

Abstract: A sump pump reservoir is disclosed, the sump pump reservoir having a housing of oblong cross-section having an interior arranged for housing at least two level-activated water pumps supported on adjacent floor areas thereof for non-interfering operation, the housing having a length substantially greater than its width and the housing having a top oblong reinforcing rim; and a cover section enclosing the interior.

Abstract: Vibration of a rotor positioned within a stator of an electric motor of an electric submersible pump assembly is attenuated in a first embodiment by adjusting the length of the rotor to position rotor bearings supporting the rotor within the stator at locations of low amplitude vibration. In a second embodiment, hydraulic pressure is applied to a fluid chamber supporting a thrust bearing that supports the rotor. When hydraulic fluid pressure is applied, the thrust bearing and the rotor move axially. Thus, moving the rotor bearings away from areas of high amplitude vibration of the rotor. In a third embodiment, a sliding mass affixed to the motor is moved in response to vibration of the motor. Movement of the sliding mass changes the vibration profile of the motor.

Abstract: A thrust module and a seal module for use in an electric submersible pump assembly is provided. The thrust module provides increased lubrication and heat dissipation while increasing sealing redundancies within the module. The thrust module includes a thrust bearing that absorbs thrust from the primary pump. A circulation pump assembly is coupled to the thrust bearing to circulate fluid through the thrust bearing and dissipate heat generated in the thrust bearing through a plurality of fins formed on an exterior surface of the circulation pump assembly. The seal module has labyrinth discs positioned within the seal module that inhibit fluid flow through the seal module. The seal module also includes check valves that release fluid from and allow fluid into the seal module at predetermined pressures. The sealing assembly is interposed between the thrust bearing and a primary pump of the electric submersible pump.

Abstract: The present invention concerns a submerged pump with electrical cables external of the cylindrical lateral wall wherein the protection means, conformed for the lodging of said cables, are predisposed to be restrained to the pump body by means of quick fixing devices associable to bayonet sliding triggers for quick and stable locking and releasing, between said means of protection and the lateral wall of the pump, with possibly interposed fixed lantern elements and a resilient protection band as a suction filter.

Abstract: An immersion motor includes a housing (3) having a wall (4) with a watertight cable penetration (5, 6; 5, 6?). The cable penetration includes an inlet (5) in the wall (4) for a cable (25) and a sealing collar (6; 6?) that can be released from the inlet (5) having a penetration (20) for the cable (25). The sealing collar (6; 6?) includes a first seal (45; 45?) disposed on the penetration (20) and means for applying force (75, 85, 90) to the first seal (45; 45?), which is designed for permanently applying force to the first seal (45; 45?) radially in the penetration (20). The cable penetration (5, 6; 5, 6?) further includes means for releasably attaching (35, 40) the sealing collar (6; 6?) to the inlet (5). At least one second seal (120, 125) is provided between the sealing collar (6; 6?) and the inlet (5).

Abstract: Systems and methods for employing gauge packages for use with a wet-connect ESPs. In one embodiment, a modular gauge package includes a body, a gauge electronics assembly housed within the body, and a pair of electrical connectors at the upper and lower ends of the body, where power is passed through the body from one connector to the other. The electrical connector at the top of the body engages a complementary electrical connector on the bottom of a pump motor. The electrical connector at the bottom of the body engages a complementary electrical connector at the end of a production conduit. The connector at the bottom of the body may be identically configured with the connector at the bottom of the pump motor, and the connector at the top of the body may be identically configured with the connector at the end of the production conduit.

Abstract: A multistage electric motor includes a plurality of motor stages connected in series, each motor stage comprising a stator, and a rotor; a plurality of cooling fluid paths, each cooling fluid path forming a recirculating loop independent of the other cooling fluid paths, each cooling fluid path in communication with the stator of one of motor stages; and a cooling fluid flowing through each cooling fluid path, the cooling fluid removing heat from the stator of each motor stage. A submersible pump including the multistage electric motor, and a method of cooling the multistage electric motor are also described.

Abstract: An oil filter can include porous material that acts to filter solid particulate matter from motor oil, that forms a chamber and that defines a central bore for receipt of a drive shaft of an electric motor forming part of a downhole device; and, disposed in at least a portion of the chamber, sorbent for removing aqueous liquids from the motor oil. A downhole device may be an electric submersible pump.

Abstract: A system, method and device may be used to monitor fluid levels in a borehole. The system includes a pulse generator to generate a pulse of electromagnetic energy to propagate along the wellbore towards a surface of the fluid, a detector to detect a portion of the electromagnetic pulse reflected from the surface of the fluid and propagated along the wellbore towards the detector, a processor to analyze detected signals to determine a level of the surface of the fluid, and a pump controller to control the operation of a pump located in the wellbore based on the fluid surface level.

Abstract: The invention is a submersible battery-operated water pump system comprised of a water pump with a plug connector that attaches to a rechargeable battery via a receptacle connector for the purpose of water recirculation as used in decorative water fountains. The submersible water pump system is designed to rest at the bottom of a water reservoir (with a minimum depth of 2 inches) to recirculate water, thus producing water flow. The plug and receptacle connectors attach to distribute electrical power from the rechargeable battery to the water pump to allow operation. The submersible, rechargeable, battery-operated water pump system is cordless, thus providing safe, portable, independent operation without the use of electrical cords or outlets.

Abstract: An apparatus includes a pump, a motor operatively coupled to the pump, and a flushing system. The motor includes a stator and a rotor disposed in a rotor cavity isolated from the stator. The flushing system is operable to provide a flushing medium to the rotor cavity.

Abstract: An electrical submersible pump motor has motor oil flowing through external circulation tubes for cooling the motor. A substantial portion of the exterior of each tube is submerged in and exposed to wellbore fluid. Heat is transferred from the motor to the motor oil, and then circulated through the external circulation tubes to conduct heat to the wellbore fluid. Internal or external motor oil pumps may be used to propel the motor oil through the circulation tubes. Guards or baffles may be used to protect the circulation tubes and to influence the flow of production fluid over the circulation tubes.

Abstract: The present invention concerns a cooling apparatus for subsea applications with a shell and tube heat exchanger. The heat exchanger includes a longitudinal shell. The shell forms a cavity with a fluid inlet port and fluid outlet port. A bundle of tubes extends from an inlet plenum chamber with an inlet port and into the shell on the same side of the shell as a bundle of tubes extending from an outlet plenum chamber with an outlet port. At least one tube sheet seals against the shell cavity and the inlet and outlet plenum chambers. The bundle of tubes extending from the inlet plenum chamber is in fluid connection with the bundle of tubes extending from the outlet plenum chamber. A retrievable pump module with a sealed pump module housing is placed adjacent the heat exchanger and includes a motor driving an ambient sea water pump.

Abstract: A system wherein cold water from near the sea floor is pumped through a primarily vertical pipe (12) to a body (14) floating at the sea surface so energy can be obtained from water temperature differences. A pump (50) located at the bottom of the pipe, is part of a pump module (46) that can be inserted and removed horizontally through a slot (44) in a bottom structure (22) lying at the bottom of the pipe. The top of the pipe is sealed to a movable pipe connector, by a U-shaped elastomeric seal (110). The pipe can include a short top pipe section (126) and a long bottom pipe section (127) of smaller diameter (D), whose upper portion can be pulled up through the top pipe section when the top pipe section is damaged.

Abstract: A heat exchanger to serve ESP equipment installed on the seabed located in either a caisson or skid. A hot oil line connects the base of the ESP motor with the externally located heat exchanger, allowing hot motor oil to be circulated through coils externally exposed to seawater. The heat from the oil is rejected to the seawater and the cooled oil is reintroduced to the motor via a cold oil line that communicates with the seal section. The heat exchanger arrangement reduces the temperature of an ESP motor, thus allowing the motor to operate longer and more reliably.

Abstract: A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well. In one embodiment, the pumping system comprises a rotary induction motor, a motor casing, one or more pump stages, and a cooling system. The rotary induction motor rotates a shaft about a longitudinal axis of rotation. The motor casing houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted. The pump stages are attached to the shaft outside of the motor casing, and are configured to impart fluid being extracted from the well with an increased pressure. The cooling system is disposed at least partially within the motor casing, and transfers heat generated by operation of the rotary induction motor out of the motor casing.

Abstract: A submersible pump system includes a submersible pump assembly having one or more stages of impellers and a submersible motor assembly that drives the pump assembly. The submersible pump assembly includes a motor housing, a motor within the motor housing for driving the pump assembly and a control module mounted to the motor housing for operating the motor. The control module is electrically connected to a power line and comprises a controller and a variable frequency drive driven by the controller. The controller operates the variable frequency drive to drive the motor to maintain a constant pressure output condition from the pump assembly.

Abstract: An immersion pump is provided, the pump having an integral housing with an inlet opening on an intake side, an outlet opening on a delivery side, a passage for electrical lines, an electronic unit for processing power and optionally information signals, an electric motor, a pressure chamber and a pump unit. The electronic unit, the electric motor, the pressure chamber and the pump unit may be pre-assembled to an insert, with the pre-assembled insert being supported on one end of the housing. An axial clamping and/or fastening system, in particular a tapered locking arrangement, is provided on the opposite end of the housing.

Abstract: A fuel pump for LPG (liquefied petroleum gas), may include a main bracket that may be mounted at a fuel tank, an integrated bracket that an end thereof may be fixed to the main bracket, the other end thereof may be extended to an inner side of the fuel tank, and the whole of the bracket may be integrally formed, and a pump unit that may be fixed to the other end of the integrated bracket with a space therebetween so as to pump liquefied fuel to an engine.

Abstract: A method of running a down hole rotary pump using a top drive, sucker rod or any drive shaft from surface. A first step involves providing a gear box having an input end and an output end. The gear box is being capable of receiving an input of a first speed at the input end and producing an output of a second speed which is one of either faster or slower than of the first speed at the output end. A second step involves positioning the gear box down hole with the input end coupled to a remote lower end of a sucker rod and the output end coupled to a rotary activated pump. A third step involves applying a driving force to the sucker rod to rotate the sucker rod at the first speed, with the rotational force being transmitted to the rotary activated pump through the gear box which rotates the rotary activated pump at the second speed.

Abstract: Systems and methods of cooling a motor of an electrical submersible pump (ESP) assembly employed in an electrical submersible subsea booster pumping system, are provided. A supporting frame structure such as an ESP mounting skid or top end assembly of a caisson having structural members exposed to environmental seawater, is modified or designed to include fluid conduits within the structural members to establish lubricant pathways for lubricant to flow. A heated/hot lubricant line connects between a supporting structure lubricant inlet port and an ESP motor lubricant outlet port. A cooled lubricant line connects between a supporting structure lubricant outlet port and an ESP motor lubricant inlet port. A pump or other fluid moving device circulates lubricant from the ESP motor to the lubricant pathways within the supporting frame structure, whereby the seawater cools the lubricant contained therein, which is then circulated back into the motor to assisting cooling the motor.

Abstract: An electric submersible progressing cavity pump (ESPCP) assembly that restricts reverse rotation of the pump motor and provides for efficient motor shutdown in the event of reverse rotation is disclosed. When the ESPCP rotates in a reverse direction, components associated with the rotating motor shaft stop rotation of the shaft to increase the torque and current of the motor, and the increased torque/current on the motor actuates a torque or current limit switch to shut off the motor. Also, particle and gas separation mechanisms are disclosed, which separate particulates and gas from the fluid flowing into the pump so that the fluid that reaches the rotor and stator assembly has a higher proportion of liquid than the resident well fluid.

Abstract: A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well. In one embodiment, the pumping system comprises a rotary induction motor, a motor casing, one or more pump stages, and a cooling system. The rotary induction motor rotates a shaft about a longitudinal axis of rotation. The motor casing houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted. The pump stages are attached to the shaft outside of the motor casing, and are configured to impart fluid being extracted from the well with an increased pressure. The cooling system is disposed at least partially within the motor casing, and transfers heat generated by operation of the rotary induction motor out of the motor casing.

Abstract: A pump unit includes a motor, a pump, a shaft spanning the motor and the pump, and at least a first magnetic bearing supporting the shaft. A hydrocarbon production system includes an underwater well and a pump unit exposed to an underwater environment. The pump unit is operable to pump a production fluid from the well and includes a motor, a pump, a shaft spanning the motor and the pump, and at least a first magnetic bearing supporting the shaft.

Abstract: An electrical submersible pump motor has motor oil flowing through external circulation tubes for cooling the motor. A substantial portion of the exterior of each tube is submerged in and exposed to wellbore fluid. Heat is transferred from the motor to the motor oil, and then circulated through the external circulation tubes to conduct heat to the wellbore fluid. Internal or external motor oil pumps may be used to propel the motor oil through the circulation tubes. Guards or baffles may be used to protect the circulation tubes and to influence the flow of production fluid over the circulation tubes.

Abstract: Subsea turbomachine for boosting the pressure of petroleum fluid flow from subsea petroleum productions wells or systems, comprising an electric motor and a compressor or pump driven by the electric motor, a fluid inlet and a fluid outlet, distinctive that the turbomachine comprises a pressure housing common for the electric motor or stator, and compressor, pump or rotor; a magnetic gear inside the common pressure housing for operative connection between the motor or stator and compressor, pump or rotor; and a partition inside the common pressure housing, arranged so as to separate a motor or stator compartment from a compressor, pump or rotor compartment.

Abstract: Apparatus for monitoring an Electrical Submersible Pump (ESP) are provided, and example of an apparatus includes a rotation rate or other sensor located in, for example, an ESP gauge. When the ESP is started the rotating elements rotate in a first direction whilst the static elements will experience an opposing torque in a second opposite direction. The small rotational movement of the ESP gauge housing, for example, is sensed by the sensor and is used to determine the direction of rotation of the motor and pump to ensure proper ESP motor and/or ESP assembly configuration.

Abstract: A shaft-locating device can include a cylindrical inner collet having an engaging surface on an inner diameter and an outward-facing tapered portion on an outer surface and an outer nut, concentrically located around the inner collet. The outer nut can have an inward-facing tapered portion that engages the outward-facing tapered portion of the inner collet, causing the inner diameter of the inner collet to become smaller, thus engaging, for example, a shaft around which the inner collet is located. In embodiments, a shoulder on the inner collet can prevent axial movement of a shaft-mounted component such as, for example, a bearing.

Abstract: An electric submersible well pump assembly includes a rotary pump and an electrical motor. The motor has a motor housing filled with a dielectric lubricant. A stator formed of a stack of stator disks with a stator bore is stationarily mounted within the motor housing. A motor shaft extends through the bore. A rotor is mounted to the shaft for rotating the shaft and has a stack of rotor disks. Axially spaced-apart radial stabilizing portions along the rotor have outer peripheries that are greater in outer diameter than remaining portions of the rotor. The outer peripheries of the stabilizing portions rotate with the rotor and are closely spaced to the inner diameter of the stator to radially stabilize the shaft.

Abstract: Provided is a fuel pump module used for a car, and more particularly, to a fuel pump module with a driver equipped inside a fuel tank capable of solving a problem of space limitation due to the installation of the driver by disposing the driver for controlling a BLDC fuel pump between a flange and a reservoir and mounting it in the fuel tank, minimizing the degradation in performance of the BLDC fuel pump caused by voltage drop and efficiency degradation due to a wire by reducing a length of a wire for electrically connecting the driver with the BLDC fuel pump, and achieving a sufficient heat radiation effect by directly transferring the heat energy generated from electrical devices such as FET, MCU, or the like, mounted in the driver to the fuel in the fuel tank through the case cover.

Abstract: A bore-hole pump formed of stainless steel comprises a head part and a foot part, between which one or more pump stages are incorporated. The foot part serves to connect the pump to a drive motor. The pump includes inlet openings for fluid to be delivered. The foot part consists of at least two components which are separated in one or more essentially radial planes and are formed with different manufacturing methods.

Abstract: An electrical submersible pumping (ESP) system for use in a wellbore having a pressure equalization system that employs modules with a bellows. The bellows axially expands and contracts in response to pressure fluctuations encountered in the wellbore. The modules are attachable in series on a lower end of a motor of the ESP to form the string, where the string can range from a single module to a multiplicity of modules, depending on the application. The bellows has a conduit axially inserted through the bellows that includes an umbilical and has an end in pressure communication with the motor.

Abstract: An electrical submersible pump assembly has a motor module coupled to a centrifugal pump module by a seal section module. A shaft assembly extends through each of the modules for causing the motor module to rotate the pump module. At least one of the modules has a sleeve extending around the shaft that is of a harder material than the shaft. A torque transmitting ring is deformed between an inner diameter of the sleeve and an exterior portion of the shaft. The inner diameter of the sleeve is a continuous cylindrical surface free of any torque transmitting shoulders. Friction created by the torque transmitting ring transmits the entire rotational force from the shaft to the sleeve.

Abstract: A labyrinth type seal section for use with an electrical submersible pump assembly having a guide tube with an axial bore to port wellbore fluid to a lower end of the seal section. Lubricating fluid fills substantially all of the seal section above an interface between the lubricating fluid and the wellbore fluid. The guide tube circumscribes a drive shaft that extends between a motor and a pump. The guide tube and shaft form an annulus filled with lubricating fluid that communicates to the well fluid and to the motor, so that pressure in the motor can be equalized to pressure of the ambient well fluid.

Abstract: A waste water lifting installation has a collection container and a pump assembly. The pump assembly is fastened on a flange plate which closes an opening on the upper side of the collection container. The flange plate, on a first side edge which faces the middle region of the waste water lifting installation, is releasably fixed on the collection container with a single locking element.

Abstract: A liquid transfer device having a housing with a top end, a bottom end, a sidewall, and an inner cavity. The sidewall has an inner surface and an outer surface. There is a plurality of openings traversing said sidewall. Also present is a filtering surface that covers the openings. The water or other liquids are pumped or transferred with a pump contained inside the inner cavity, with a fluid exit used for carrying the water out towards exterior hosing.

Abstract: A submersible turbine pump (STP) comprising a manifold, a yoke assembly including a yoke sleeve integrally connected to the manifold, and a packer removably secured to the manifold is provided. The manifold includes an electrical cavity that receives electrical wiring from an external source. The yoke sleeve has a hollow interior and is integrally connected to manifold, and a first end of the yoke sleeve is within the electrical cavity. The packer includes a chamber having a yoke sleeve inlet port and an electrical conduit inlet port. The yoke sleeve inlet port receives a second end of the yoke sleeve extending from the manifold, and the electrical conduit inlet port receives an electrical conduit extending from a pump within an underground storage tank. The electrical wiring passes from the electrical cavity to the chamber through the yoke sleeve and then to the pump through the electrical conduit.

Abstract: Systems and methods in which output power that would conventionally be provided by surface equipment to drive downhole equipment, is transformed to increase the voltage before transmitting the power over a power cable to downhole equipment. The downhole equipment includes a step-down transformer that receives power from the power cable at a voltage which is too high to drive the motor or other downhole equipment and reduces the voltage to a level that is suitable for use by the downhole equipment. The step-down transformer may utilize toroidal transformers that are positioned around other components of the system, such as the shaft that couples a motor to an electric submersible pump. The step-down transformer may be configured as a modular unit that can be inserted between components (e.g. motor and seal) that are manufactured using conventional designs.

Abstract: A submersible pumping system for use downhole, wherein the system includes a pump, a pump motor, a seal section, a shaft coupling the pump motor to the pump, and bearing assemblies for radially retaining the shaft in place that are offset with respect to an axis of the shaft. The offset bearing assemblies produce side loads in the shaft that reduce shaft vibration during use. The bearing assemblies can be a combination of symmetric and asymmetric assemblies set in an alternating pattern along the length of the shaft.

Abstract: A system for monitoring an Electrical Submersible Pump is disclosed comprising a rotation rate sensor located in an ESP gauge (6). When the Electrical Submersible Pump is started the rotating elements rotate in a first direction while the static elements will experience an opposing torque in a second opposite direction. The small rotational movement of the ESP gauge housing is sensed by the sensor and is used to determine the initial direction of rotation of the motor (5) and pump (6).

Abstract: A bearing assembly for use in a deepwell submersible pump, the pump and a method of pumping a geothermal fluid. The bearing assembly is constructed to include a lubricant conveying mechanism, a bearing sleeve and a multilayer bushing. The lubricant is forced between the bushing and a bearing sleeve by the lubricant conveying mechanism that cooperates with the rotation of a shaft used to connect a power-providing motor with one or more pump impellers. In this way, there exists a substantially continuous lubricant environment between the sleeve and bushing to act in a hydrodynamic fashion.

Abstract: This invention relates to a pump system, especially for boosting the flow rate of a fluid through a pipe (1, 2, 6), comprising a pump positioned in a pump chamber (10) for pumping at a chosen rate, and a motor driving said pump, the motor being positioned in a chamber (9) being provided with a pressurized fluid, the pressure of which being higher than the pressure in the pump chamber, the motor and the pump chambers being separated by a seal (8), the seal allowing a leakage of said pressurized fluid between them, wherein the pressurized fluid is acceptable to the pump environment and the system comprises a discharge branch line (3) coupled to the pipe(6) and positioned downstream from said pump, the discharge branch line having an outlet into the environment.