Abstract: A system includes a vertical charge pump assembly. The vertical charge pump assembly includes a top portion adjacent to a first end of the vertical charge pump assembly and a bottom portion adjacent to a second end of the vertical charge pump assembly. A pump motor is disposed in the top portion and an impeller is disposed in the bottom portion within a bowl casing. A shaft is disposed within a central passageway and connects the pump motor with the impeller. The vertical charge pump assembly also includes an inlet at the second end below the bowl casing. The pump inlet and the bowl casing are configured to be immersed in a fluid, and the vertical charge pump assembly is configured to pump the fluid into the inlet and upwards through the central passageway by rotation of the impeller. A vibration sensor is disposed on an external surface of the bottom portion, on or proximate to the bowl casing and the pump inlet.

Abstract: A centrifugal compressor comprises an impeller including a hub and a plurality of blades. Each blade has a positive pressure surface and a negative pressure surface extending from one side of an external radial surface toward the other side of the external radial surface and being of a positive pressure and a negative pressure, respectively, when the impeller rotates. The hub has a lightening hole that opens to the external radial surface between the positive pressure surface and the negative pressure surface of the plurality of blades. The lightening hole is provided closer to the positive pressure surface of the blade than the negative pressure surface of the blade.

Abstract: A centrifugal compressor comprises an impeller including a hub and a plurality of blades. The hub is provided with a through hole. The hub has an external radial surface having an inner external radial surface and an outer external radial surface. The outer external radial surface is formed closer to a back surface than an imaginary curved surface having as a radius a radius of curvature of the inner external radial surface at a radially outer edge thereof.

Abstract: A thrust balancing apparatus for a pump includes a housing, a balancing chamber, a connecting tube, a balancing disk, a bushing, a washer, and a pair of upthrust washers. The balancing chamber defines an upper cavity and a lower cavity. The connecting tube is configured to establish fluid communication between the balancing chamber and an exterior of the housing. A first portion of the balancing disk is disposed within the upper cavity. A second portion of the balancing disk passes through the lower cavity. A third portion of the balancing disk is external to the balancing chamber. The washer is disposed between the balancing disk and the bushing. The pair of upthrust washers are disposed between the balancing disk and the balancing chamber.

Abstract: A bearing system includes a bearing housing that includes a sleeve and a mounting structure for connecting the bearing system to a compressor housing. The sleeve has a radial inner surface that defines a cylindrical bore, and includes a locking feature located along the radial inner surface. The mounting structure is located radially outward from the sleeve. The bearing system also includes a foil bearing assembly positioned within the cylindrical bore. The foil bearing assembly includes an outer foil, an inner foil, and a bump foil positioned between the outer foil and the inner foil. At least one of the outer foil and the inner foil includes a bearing retention feature cooperatively engaged with the locking feature to maintain the foil bearing assembly within the bearing housing at a fixed rotational position.

Abstract: The preferred embodiments of the present invention provide two advantageous features, which are especially beneficial in combination, but which can be advantageously and beneficially employed independently of one another: (1) firstly, a self-cooling motor bearing system; and (2) secondly, a self-lubricating motor bearing system. In the preferred embodiments, one or both of these two advantageous features are integrated inside an electric motor (e.g., within the electric motor's enclosure housing) in such a manner as to greatly enhance bearing operating conditions (e.g., maintaining adequate bearing lubrication and/or bearing operating temperature) without the use of external lubrication units and/or external cooling units.

Abstract: An impeller includes a base plate, a hub protruding from the base plate, and a number of blades connected to the base plate and extending from a lateral surface of the hub toward an edge of the base plate. Opposite sides of each of the blades are a working surface and a non-working surface. The base plate is divided into a plurality of sub-plates by the plurality of blades. Each of the sub-plates is located between two adjacent blades and connected to the non-working surface of one of the two adjacent blades and the working surface of the other one of the two adjacent blades. A distance from an edge of each of the sub-plates to a center of rotation of the impeller is varied.

Abstract: An impeller designed for use in radial pumps. The impeller compensates for axial forces during pumping operations. The impeller utilizes vanes having 3D geometry which extend from the impeller intermediate plate eye to the external diameter of the intermediate plate. On the backside of the intermediate plate, the vanes define a plurality of hydraulic passages. The hub plate also includes a series of balancing holes.

Abstract: A rotary machine includes a seal device capable of restricting a flow of a fluid in a clearance between a stationary member and a rotational member. The seal device includes a pressure loss element mounted to the stationary member, a first non-contact type seal protruding from the rotational member toward the pressure loss element and facing the pressure loss element via a first gap, and a second non-contact type seal protruding from the stationary member toward the rotational member, facing the rotational member via a second gap, and being positioned on one side of the pressure loss element in a flow direction of the fluid. The seal device also includes a contact type seal protruding from the stationary member toward the rotational member and being disposed downstream of the pressure loss element and the second non-contact type seal in the flow direction of the fluid.

Abstract: A multi-stage pump featuring first and second stages, each stage having an impeller arranged on a rotor of the pump, each impeller having a hub-side and an eye-side, and each impeller configured to pump a liquid through the pump that applies an axial thrust load caused by a pressure difference in an axial direction from the hub-side to the eye-side of each impeller; and a first and second stage pump casing, each casing configured to form a casing enclosure to contain components of the first stage and the second stage, including each impeller, and configured with one or more pump casing openings formed therein and passing thru the pump casing to leak at least some liquid being pumped from inside to outside the casing enclosure to reduce substantially the axial thrust load caused by the pressure difference in the axial direction from the hub-side to the eye-side of each impeller.

Abstract: A centrifugal pump includes a motor having a shaft, and an impeller engaged with an end portion of the shaft such that a rotation of the impeller relative to the shaft is limited. The impeller includes a main panel engaged with the shaft, a plurality of passage walls extending from the main panel in an axial direction, a side panel in contact with end surfaces of the passage walls that face away from the main panel, the side panel having an inflow opening at a radially center part, and a fluid passage that is defined by the passage walls adjacent to each other in a circumferential direction, the fluid passage communicating with the inflow opening. The side panel includes an engagement portion configured to be engaged with a fixation jig that limits a rotation of the impeller during fixing the impeller to the shaft by screwing a nut.

Abstract: A pump arrangement, particularly a magnetic clutch pump arrangement, includes a containment can with a central longitudinal axis which hermetically seals an enclosed chamber with respect to the inner chamber formed by the pump housing. The containment can has a base with at least one bead extending into the inner chamber. The at least one bead is radially spaced from the central longitudinal axis of the containment shell by at least one defined distance relationship. A method for producing a containment can for a pump arrangement is also provided.

Abstract: An object is to provide a rotary fluid element and a method of correcting unbalance of a rotary fluid element, whereby unbalance of the rotary fluid element can be corrected multiple times in a necessary and sufficient amount without sacrificing strength of blades. A rotary fluid element includes: a plurality of blades extending in a centrifugal direction on an outer peripheral surface of a boss portion and disposed at intervals in a circumferential direction; and a cut-remove portion for reducing unbalance disposed in a blade gap between the blades adjacent in the circumferential direction. The cut-remove portion includes a first cut-remove portion which is cut and removed on a radially-outer rim portion between the blades, and an additional cut-remove portion which is cut and removed on a radially-inner portion disposed inside the first cut-remove portion with respect to a radial direction.

Abstract: An outer wall surface of an output end portion includes a pair of first plane surfaces which are formed at different positions in its circumferential direction. An inner wall surface of a fitting hole includes a pair of second plane surfaces which are formed at different positions in the circumferential direction. A clearance between one of the pair of first plane surfaces and one of the pair of second plane surfaces is made larger from one side toward the other side in an axial direction in a state that a rotary shaft and an impeller are concentric with each other.

Abstract: An impeller for used in a fluid pump device includes a shaft controlled to revolve in a first direction; an impeller body coupled to the shaft and driven by the revolving shaft to rotate, the impeller body having a top surface, a bottom surface and a circumferential surface; a first set of fluid-guiding members disposed on the top surface of the impeller body for driving a fluid to flow along a centrifugal direction of the revolving shaft; and a second set of fluid-guiding members disposed on the circumferential surface of the impeller body. Each or at least one of the second set of fluid-guiding members has a titling structure for driving the fluid to flow from the top to the bottom of the impeller along a designated path on the circumferential surface.

Abstract: A compressor (22) has a housing assembly (50) with a suction port (24) and a discharge port (26). An impeller (54) is supported by a shaft (70) which is mounted for rotation to be driven in at least a first condition so as to draw fluid in through the suction port (24) and discharge the fluid from the discharge port (26). A magnetic bearing system (66, 67, 68) supports the shaft (70). A controller (84) is coupled to an axial position sensor (80) and is configured to control impeller position.

Abstract: The present invention relates to a centrifugal pump, the impeller of which comprises a shroud (34) with at least one solid and rigid working vane (36), and at least one solid and rigid rear vane (38), the at least one working vane (36) having a leading edge region (46), a trailing edge region (48), a central region (C), a side edge, a pressure face (42) and a suction face (44), the at least one solid and rigid rear vane (38) having a trailing edge region, a side edge, a pressure face and a suction face. The trailing edge region (48) of the at least one working vane (36) is rounded by means of a rounding to have a thickness greater than that in the central region (C).

Abstract: A compressor that includes a frame, a rotor assembly, and a heat sink assembly. The rotor assembly includes a bearing assembly to which the heat sink assembly is secured. The compressor is configured such that, during use, air is drawn through the interior of the frame. The heat sink assembly then extends radially from the bearing assembly into the air path through the frame such that the air flows over the heat sink assembly.

Abstract: A shock absorber comprising a generally tubular body defining a working chamber. A piston is slidable in the working chamber and separates a compression chamber from a rebound chamber of the working chamber. The working chamber contains damping fluid. The shock absorber comprises an electric generator fitted thereto. The generator comprises a turbine rotatably coupled to at least one magnet and coils adjacent the magnet. The shock absorber comprising a turbine flow path between the compression chamber and the rebound chamber, the turbine being supported for rotation in the turbine flow path driven to rotate by flow of damping fluid. Preferably the turbine flow path comprises a compression flow path and a rebound flow path and a turbine chamber, the compression flow path providing for flow of damping fluid from the compression chamber though the turbine chamber to the rebound chamber.

Abstract: A centrifugal compressor including: a casing; at least one impeller supported for rotation in the casing and provided with a hub, a shroud and an impeller eye; an impeller-eye sealing arrangement, for sealing the impeller in the region of said impeller eye. The centrifugal compressor further includes at least one cooling-medium portlocated at the impeller-eye sealing arrangement, arranged for delivering a cooling medium around the impeller eye.

Abstract: A turbomachine having a cooling device for supplying cooling air onto a compressor region from an air distribution chamber is disclosed, the air distribution chamber being arranged between an outlet diffuser of a compressor and a combustion chamber, where the cooling device has cooling air pipes for supplying cooling air from the air distribution chamber into a cavity between the outlet diffuser and a rotor segment of the compressor.

Abstract: A compressor that includes an impeller, a diffuser and a shroud. The diffuser includes vanes and one or more projections, each of which extends from a top of a vane. The shroud includes one or more holes. The shroud covers the impeller and the diffuser such that each projection protrudes through one of the holes. The shroud is then secured to the projections by an adhesive.

Abstract: A cooling option for a steam turbine is provided, wherein the steam turbine includes a high-pressure zone and a medium-pressure zone, wherein the saturated steam streaming out of the high-pressure zone is discharged via a saturated steam conduit to a first pressure chamber in a second flow channel of the medium-pressure zone and thus the possibility of the saturated steam causing damage by corrosion and erosion in the high-pressure zone is prevented.

Abstract: Apparatus, including a vertical double-suction pump, is provided featuring a pump casing and a double suction impeller arranged therein on a shaft. The pump casing has a pump casing wall. The double suction impeller has upper and lower shrouds with metal rims configured to form upper and lower isolating annuli between the double suction impeller and the wall of the pump casing in order to impede a recirculation flow from an impeller discharge to be able to act of the upper and lower shrouds and create a controlled axial thrust load from differentiated hydraulic pressure on the upper and lower shrouds. The upper and lower isolating annuli may also be geometrically varied between the upper and lower shrouds of the double suction impeller to create a pressure differential in a direction parallel to an axis of rotation of the double suction impeller.

Abstract: A multi-stage axial compressor for counter rotation. A first series of rotor blade assemblies are mounted on and rotate with the driveshaft, each rotor blade assembly of the first series comprising a rotating stage of the multi-stage axial compressor. A second series of rotor blade assemblies provide a counter-rotating stage of the multi-stage axial compressor. An accessory drive links the second series of rotor blade assemblies to the driveshaft and causes counter-rotation of the second series of rotor blade assemblies.

Abstract: The pump includes a stator and a rotor having an impeller in which a fluid duct passes. An axial balancing device arranged on this wheel includes a rear balancing chamber and a passage arranged between the wheel and the stator, enabling evacuation of fluid from the fluid duct to the balancing chamber. The pressure of fluid in the balancing chamber compensates the pressures exerted by the fluid on the rest of the rotor allowing axial balancing of the rotor. The passage includes an upstream nozzle and a downstream nozzle, as well as an intermediate annular chamber, arranged between walls of the wheel and of the stator, the intermediate chamber being arranged downstream of the upstream nozzle and upstream of the downstream nozzle.

Abstract: A mechanical coolant pump for an internal combustion engine includes a pump rotor wheel comprising a blocking ring and rotor blades. The rotor blades are configured to pump a coolant radially outwardly. Variable pump stator blades are pivotably supported by a static blade holding ring at a first axial blade end. The variable pump stator blades are arranged radially outwardly of the pump rotor wheel. The blocking ring is arranged to partially overlap a second axial blade end.

Abstract: A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

Abstract: An impeller includes a plurality of vanes formed around a hub, each of the plurality of vanes defines an offset between a leading edge and a trailing edge.

Abstract: A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

Abstract: An impeller or axial stage compressor disk backface shroud for use with a gas turbine engine is disclosed. The backface shroud includes, but is not limited to, a substantially funnel shaped body having a surface. The substantially funnel shaped body is configured to be statically mounted to the gas turbine engine substantially coaxially with the impeller or axial stage compressor disk. The surface and a backface of the impeller or axial stage compressor disk form a cavity that guides an airflow portion to a turbine when the substantially funnel shaped body is mounted coaxially with the impeller or axial stage compressor disk and axially spaced apart therefrom. The airflow portion has a tangential velocity and a recessed groove in the surface of the backface shroud is oriented generally transversely to the tangential velocity to at least partially interfere with the airflow portion, thus affecting static pressure in the cavity.

Abstract: A slinger shield structure is provided and includes a first annular disc, having a body, opposing faces defining an aperture extending through the body and through-holes extending through the body, which are arrayed around the aperture, a second annular disc having a body and opposing faces defining an aperture extending through the body, a hub for connection with the first and second annular discs at the respective apertures and radial vanes suspended between the first and second annular discs at a distance from the hub to define radial channels between adjacent radial vanes and drainage channels between the radial vanes and the hub.

Abstract: The invention provides a supercharger which is provided with a thrust bearing in an outer side of a radial bearing, and can smoothly discharge a fed lubricating oil from a bearing portion so as to reduce a resistance generated by the lubricating oil. The supercharger is provided with a thrust bearing (30) rotatably supporting a thrust force applied to a turbine shaft (12). The thrust bearing (30) is constituted by a disc-shaped thrust collar (32) rotating together with the turbine shaft, and a turbine side thrust bearing (34) and a compressor side thrust bearing (36) inhibiting a movement in an axial direction of the thrust collar.

Abstract: An electrical submersible pumping system having a pump, a motor, a shaft connecting the pump and motor. Coaxially stacked rotating impellers and stationary diffusers are coaxially housed within the pump. Radial ports are formed in a hub of the diffusers that direct fluid pressurized by an impeller to a cavity formed on the shroud of the impeller. Axial ports are formed in the shrouds of the impellers that direct fluid from the cavity to a fluid flow passage within the impeller. Strategic placement and sizing of the radial and axial ports balances thrust forces exerted onto the impeller.

Abstract: A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

Abstract: A fluid machine and method of operating the same includes a pump portion having a pump impeller chamber, a pump inlet and a pump outlet and a turbine portion having a turbine impeller chamber, a turbine inlet and a turbine outlet. A shaft extends between the pump impeller chamber and the turbine impeller chamber. The shaft has a shaft passage therethrough. A turbine impeller is coupled to the impeller end of the shaft disposed within the impeller chamber. The turbine impeller has vanes at least one of which comprises a vane passage therethrough. A thrust bearing is in fluid communication with said vane passage.

Abstract: Systems and methods for improving seal performance in a centrifugal water pump for an internal combustion engine increase static pressure at the seal by incorporating a combination of slots and ribs into a seal cavity of the pump housing that are positioned to convert dynamic fluid pressure into static pressure at the seal while reducing coolant velocity at the seal. Vent holes in the impeller having an appropriate size and location may also be used to increase the static pressure at the seal to enhance seal performance.

Abstract: A rotary-type fluid machine which enables practical and effective operation in an extremely low specific speed range. The rotary-type fluid machine (1, 1?) has an impeller (10, 10?) integrally connected to a rotating drive shaft (2). The impeller is accommodated in a casing (3). Fluid (a) of a suction fluid passage (4) to be pumped flows into a center part (11) of the impeller. The fluid (b) is discharged from a peripheral portion (12) of the impeller by the effect of the centrifugal force of the rotating impeller, so that the fluid is delivered through a delivery fluid passage (5) outside of the casing. Many grooves (15) extending toward a peripheral edge of the impeller from the center part of the impeller are formed on the impeller. The groove opens on an outer circumferential surface (18) of the impeller, and causes strong recirculation vortices (R) to be formed in the vicinity of the peripheral edge of the impeller when the impeller rotates.

Abstract: A turbomachine arranged with a rotor and a stator, including a radial positioning device ensuring that the rotor is radially positioned; and a contactless axial balancing device arranged on at least one bladed wheel for axially balancing the rotor at high speed. The turbomachine includes a thrust bearing distinct from the radial positioning device serving to balance the rotor axially at low speed, and without contact at high speed. In addition, the radial positioning device is constituted by hydrostatic bearings, the turbomachine including hydrostatic bearing feed circuits suitable for connecting the bearings to a source of fluid under pressure. As a result, it is possible to obtain operation at high speeds with a very long lifetime.

Abstract: A fuel pump has a casing and an impeller. The impeller is substantially disk shaped having an upper surface and a lower surface The impeller is rotatable within the casing around a rotational axis. A plurality of impeller depressions is formed in at least the lower surface of the impeller. The plurality of impeller depressions is located on at least one of the inside and the outside of a group of concavities. The plurality of impeller depressions is arranged on a circle around the rotational axis of the impeller. Each of the impeller depressions has its deepest portion in a rear half thereof with respect to the rotational direction of the impeller.

Abstract: A turbo-machine including a volute casing, a rotating shaft, an impeller, seals, an axial thrust control member and a bellows unit. The volute casing defines therein a fluid passage. The rotating shaft is rotatably provided in the volute casing. The impeller is coupled to the rotating shaft to draw fluid using centrifugal force. The seals are provided around the front and rear ends of the impeller to prevent leakage of fluid. The axial thrust control member is installed in the volute casing behind the impeller. The bellows unit includes the piston installed in the volute casing in a shape surrounding a circumferential outer surface of the axial thrust control member; and a bellows connected with one surface of the piston, the bellows having the predetermined elasticity; and an internal space, between the piston and the volute casing, isolated from the fluid drawn behind the impeller.

Abstract: In one embodiment a centrifugal impeller has an axis of rotation, a plurality of blades, and a plurality of pitches defined between the blades. A cavity may be formed in a back side of the impeller, opposite with at least one of the plurality of pitches. In one form the cavity may not extend below a radius determined according to a stress criteria or stress limitation.

Abstract: An impeller for a centrifugal pump that includes a disk-shaped shroud having a central axis, a front surface, a rear surface, and a circular perimeter, and a hub at the center of the shroud, the hub having an axial bore. The impeller further includes a first set of vanes on the front surface of the shroud, the first set of vanes extending radially inward from the perimeter towards the hub, a second set of vanes on the rear surface of the shroud, the second set of vanes extending radially inward from the perimeter towards the hub, a balancing area on the rear surface of the shroud, the balancing area extending radially outward from the hub, and a number of openings in the shroud, the number of openings configured to allow a fluid to pass from one side of the shroud to the other.

Abstract: Disclosed is a steam turbine comprising an exterior housing and an interior housing. The exterior housing and the interior housing are provided with a fresh steam supply duct. A rotor that encompasses several impeller blades and a thrust-compensating piston is rotably mounted within the interior housing. The interior housing is equipped with several guide blades that are disposed such that a flow duct comprising several blade stages, each of which comprises a series of impeller blades and a series of guide blades, is formed along a specific direction of flow. The interior housing is further equipped with a recirculation duct which is embodied as a pipe that communicates between a space located between the interior housing and the exterior housing and the flow duct downstream of a blade stage.

Abstract: Disclosed is a steam turbine with a casing, wherein a turbine shaft having a thrust-compensating piston is rotatably mounted inside the casing and directed along a rotation axis, wherein a flow passage is formed between the casing and the turbine shaft. The turbine shaft has in its interior a cooling line for directing cooling steam in the direction of the rotation axis. The cooling line, on one end, is connected to at least one inflow line for the inflow of cooling steam into the cooling line from the flow passage, and on the other end, is connected to an outflow line for directing cooling steam onto a lateral surface of the thrust-compensating piston. An essential aspect is, the cooling steam discharging onto the lateral surface of the thrust-compensating piston mixes with some of the live steam and is directed back into the flow passage via a return line arranged in the casing.

Abstract: A high pressure first stage turbine and seal assembly are described. In one embodiment, a high pressure turbine section is provided. The turbine section includes at least one stage, at least one rotor and a bucket assembly. The bucket assembly includes a bucket and an attachment fixture. The stage has a high root reaction during operation. An intermediate space is between the bucket assembly and a stationary component of the turbine section. A seal is provided between the stationary member and the rotor to facilitate preventing leakage from the intermediate space toward an end of the stage. Steam balance holes are provided in the rotor or the bucket to facilitate feeding steam towards an end of the turbine stage.

Abstract: A centrifugal pump includes a casing having an impeller chamber, an inlet, an outlet, and a bearing chamber. A shaft disposed within the casing has an impeller end and a motor end. The impeller is coupled to the impeller end of the shaft and is disposed within the impeller chamber. A bearing is disposed within the bearing portion. The bearing has an inboard end with an inboard-bearing surface and an outboard end with an outboard-bearing surface. The bearing and the shaft have a bearing clearance therebetween. A disc is coupled to the shaft on the impeller end which is spaced apart from the inboard-bearing surface. A seal ring is disposed between the disc and the inboard-bearing surface. The shaft, the seal ring, the disc, and the inboard-bearing surface define a thrust chamber therebetween. The thrust chamber is in fluid communication with the impeller chamber through the bearing clearance so that an axial thrust in an inboard direction is generated by the thrust chamber.

Abstract: A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller.

Abstract: A machine for recovering power from a flow of compressed gas, for example, natural gas includes a turbo-expander having a turbo-expander wheel, and a generator having a rotor able to be driven by the turbo-expander wheel and a stator about the rotor. The turbo-expander and the generator are housed in a length of pipe. The turbo-expander wheel has an obverse side facing the generator. There is a flow passage for the flow of expanded gas that places the obverse side of the wheel in gas flow communication with an outer surface of the stator. This outer surface typically carries fins to facilitate cooling of the stator by expanded gas from the turbo-expander.

Abstract: A first centrifugal impeller and a second centrifugal impeller are arranged in such an orientation that back sides of the first centrifugal impeller and the second centrifugal impeller face to each other. Bearings are cylindrical roller bearings and a thrust bearing. The cylindrical roller bearings are arranged at two axially spaced supporting positions respectively, and support a radial load applied to the rotating shaft. The thrust bearing supports a thrust load applied to the rotating shaft.