Abstract: A centrifugal pump has a stationary diffuser with a bore. A thrust bearing has a tubular portion that inserts into the bore. The thrust bearing has an external shoulder that contacts a support surface in the bore of the diffuser for transmitting downward thrust from an upstream impeller to the diffuser. The thrust bearing has an internal shoulder for transmitting upward thrust from a downstream impeller to the diffuser.

Abstract: An exemplary clamp for clamping a bearing cartridge and shaft subassembly of a turbocharger includes an upper portion, a lower portion where the upper portion and the lower portion form a bore having a bore diameter sized to clamp a bearing cartridge and a fluid passage defined in part by the upper portion, the lower portion or the upper portion and the lower portion where the fluid passage includes an opening to the bore. Various other exemplary devices, systems, methods, etc., are also disclosed.

Abstract: A method for axial thrust control of a gas turbine, and a gas turbine with a device for controlling axial thrust are provided. A gas turbine, with regard to aerodynamic forces and pressure forces, which exert an axial force upon the rotor, is configured such that at no-load and low partial load it has a negative thrust, and at high load it has a positive thrust. In order to ensure a resulting positive thrust upon the thrust bearing within the entire load range of the gas turbine, an additional thrust is applied in a controlled manner. The additional thrust for example can be controlled in dependence upon the gas turbine load. The resulting thrust force at full load is consequently less than in the case of a conventionally designed gas turbine without thrust balance.

Abstract: An air-guiding system between a compressor and a turbine of a gas turbine engine includes an air chamber (5) being delimited by the inner casing of the combustion chamber (4) and first and second seals (7, 8) towards the rotating compressor shaft cone (12). An axial thrust compensation chamber (6) is adjoined to said second seal (8) and respectively loaded with the turbine cooling air (B?, C) branched-off from the compressor air. Due to the higher pressure in said axial thrust compensation chamber with respect to said air chamber, the high axial forces are compensated. The air flowing back into said air chamber through said second seal (8) is guided and separated from components (10) and flowing-off air masses by a flow-guiding means (16) in said air chamber. This results in a high rinsing effect, a reduced vortex formation and finally, a reduced thermal stress.

Abstract: An air cycle machine includes a housing having a compressor housing portion. A shaft is supported by the housing and includes a thrust runner. A hydrodynamic thrust bearing is arranged adjacent to the thrust runner and includes upstream and downstream sides. A compressor rotor is mounted on the shaft. A seal is arranged between the compressor rotor and the compressor housing portion. An orifice is provided in the compressor housing portion at the downstream side of the hydrodynamic bearing. The orifice vents hot compressed air that may leak past the seal prior to reaching the hydrodynamic thrust bearing.

Abstract: The non-axial force exerted on a pneumatic tool by a non-axial air supply is balanced to allow for uniformly radially distributed compliance forces on the tool. An annular air ring is disposed around the pneumatic tool, covering an air inlet port. Air is supplied by any route to a first air passage that supplies the air to the interior of the annular air ring, exerting a force on the annular air ring. Air flows in the annular space of the air ring, entering the tool air inlet port to drive the pneumatic tool. One or more second air passages are connected to the annular air ring in an even radial distribution. Each second air passage is connected to the air source, or terminates in an air blockage, creating a column of pressurized air that exerts a force on the annular air ring equal to the first air passage. The forces exerted on the air ring are thus balanced with respect to the axis of the tool.

Abstract: A method of assembling a gas turbine engine includes providing a gas turbine engine including a compressor, a combustor downstream from the compressor, and a turbine coupled to the compressor, and coupling a seal assembly aft of the compressor such that air discharged through the seal assembly facilitates reducing the cavity pressure, and therefore reducing the axial forces induced to an aft side of the compressor.

Abstract: A pump for the transporting of fluids and/or of mixtures of fluids includes a housing (1) and at least one restrictor gap seal which is provided in the housing (1) to reduce the pressure in a restrictor gap along a rotatable part (2) of the pump, wherein the restrictor gap seal is formed as a brush seal arrangement (8). The brush seal arrangement (8) contains one or more individual brush seals (8?) which include as sealing members a plurality of sealingly arranged fibers, bristles and/or wires (8a) which are distributed and fastened in ring form and whose free ends extend towards the surface to be sealed.

Abstract: A turbine shaft may be used to remove a heat load from pliant bearings without requiring the use of a process fluid for cooling the turbine shaft. The turbine shaft comprises a heat conductive sleeve disposed between an outer surface of a tie rod shaft and an inner surface of a bearing journal; the heat conductive sleeve having a sleeve inner surface separated from a sleeve outer surface by a sleeve thickness; the heat conductive sleeve having a first end separated from a second end longitudinally about a center axis; the sleeve outer surface being in physical contact with the inner surface of the bearing journal; and the heat conductive sleeve having a thermal conductivity that is greater than a thermal conductivity of the bearing journal.

Abstract: A method and system for actively controlling thrust pressure in a steam turbine is disclosed. The method may comprise monitoring a thrust pressure affecting a thrust fitting in a steam turbine, and adjusting the thrust pressure to maintain a desired thrust pressure on the thrust fitting in the steam turbine.

Abstract: The rotor (5) of a gas turbine containing a compressor part (1) and a turbine part (3) is mounted in an axial thrust bearing (19) and in two radial journal bearings (16, 17). One of the bearings is a journal bearing (16) arranged in the intake area of the compressor part (1) and the other journal bearing (17) together with the thrust bearing (19) is arranged in the area of the turbine part (3).

Abstract: A front cover 5 of a converter cover 4 is formed with a punched hole 12, a thrust bearing 13 having the same outer shape as that of the punched hole 12 is fitted to the punched hole 12, a bearing housing 14 is fitted to the outside, thereby tightly closing the converter cover 4 to support the thrust bearing 13. A thrust applied from a turbine hub 9 to the thrust bearing 13 is received by a flange 14b of the bearing housing 14.

Abstract: A rotor and bearing system for a turbomachine. The turbomachine includes a drive shaft, an impeller positioned on the drive shaft, and a turbine positioned on the drive shaft proximate to the impeller. The bearing system comprises one gas journal bearing supporting the drive shaft between the impeller and the turbine. The area between the impeller and the turbine is an area of increased heat along the drive shaft in comparison to other locations along the drive shaft. The section of the drive shaft positioned between impeller and the turbine is also a section of the drive shaft that experiences increased stressed and load in the turbomachine. The inventive bearing machine system positions only one radial bearing in this area of increased stress and load.

Abstract: An axial thrust balancing system for a centrifugal compressor, having improved safety characteristics, the centrifugal compressor comprising a rotor having impellers adjacent to each other and connected by a shaft, the rotor rotating in a stator, the centrifugal compressor additionally including a balancing piston, a balancing line being provided between an intake of a first compression stage and an area downstream of the balancing piston; this system comprises an intake mechanical gas seal around the shaft upstream of the first compression stage and an outlet mechanical gas seal downstream of the balancing piston, the balancing line being closable by blocking elements.

Abstract: An axial thrust balancing system (10) for a centrifugal compressor (12), having improved safety characteristics, the centrifugal compressor (12) comprising a rotor (14) having impellers (16) adjacent to each other and connected by a shaft (18), the rotor (14) rotating in a stator (20), the centrifugal compressor (12) additionally including a balancing piston (22), a balancing line (24) being provided between an intake of a first compression stage and an area downstream of the balancing piston (22); this system (10) comprises an intake mechanical gas seal (26) around the shaft (18) upstream of the first compression stage and an outlet mechanical gas seal (28) downstream of the balancing piston (22), the balancing line (24) being closable by means of blocking elements (32).

Abstract: The invention relates to a turbine (1) having a rotor (2), which has a bladed area (3) for rotor blades (4) and a thrust compensation piston (5). The thrust compensation piston (5) has a hot side (6), which faces the bladed area (3), and a cold side (7), which is remote from the bladed area (3). On one side, a feed (14) for sealing fluid (15), which is assigned to the cold side (7), and a leakage fluid feed (12), which is flow-connected to the bladed area (3), open out into a mixing area (13), and on the other side a discharge line (16) branches off from the mixing area. The invention also relates to a method for discharging hot leakage fluid (17). In a turbine (1), the leakage fluid (17) passes through a radial gap (12) between a thrust compensation piston (5) of a rotor (2) and a stationary turbine part (11) and is mixed with a cooler sealing fluid (15) and discharged.

Abstract: This invention relates to rotary pumps adapted, but not exclusively, for use as artificial hearts or ventricular assist devices and, in particular, discloses in preferred forms a seal-less shaft-less pump featuring open or closed (shrouded) impeller blades with the edges of the blades used as hydrodynamic thrust bearings and with electromagnetic torque provided by the interaction between magnets embedded in the blades and a rotating current pattern generated in coils fixed relative to the pump housing.

Abstract: A steam cooling system (30) and associated methods are provided which have a first high pressure (HP) steam turbine (12) having a straight through configuration, a second intermediate pressure (IP) steam turbine (16) having a straight through configuration positioned adjacent the first HP steam turbine (12), and a balance piston (40) positioned adjacent the inlet (17) of the second IP steam turbine (16) and between the second IP steam turbine (16) and the first HP steam turbine (12). A steam cooling conduit (32) is preferably positioned to have an inlet adjacent the first HP steam turbine (12) and an outlet adjacent the balance piston (40) for providing a steam cooling path therebetween.

Abstract: A gas turbine arrangement includes a compressor (2) with a compressor rotor (7), a turbine (3) with a turbine rotor (12) and connected with the compressor (2), and a balancing member (18) connected with the turbine rotor (12) and arranged to counteract axial forces generated by the compressor rotor (7) and the turbine rotor (12). The balancing member (18) is arranged to be activated by a pressure fluid. The arrangement includes at least one channel (26) which is arranged to lead at least a part of the pressure fluid used for activation to at least a part of the turbine (3) for influencing the temperature of the turbine part, and where the part of the turbine (3) is a rotor portion (13), wherein the balancing member (18) is attached to that end of the turbine rotor (12) which is located downstream, and where the channel (26) leads to a space (25) which is formed between the end of the turbine rotor (3) and the balancing member (18).

Abstract: A steam turbine has a turbine shaft directed along a turbine axis. A plurality of turbine stages, each include a guide-blade structure and a moving-blade configuration located axially downstream of the guide-blade structure. The guide-blade structure and the moving-blade configuration are provided along the turbine shaft. Each stage has an average reaction degree achievable between 5% and 70%. The reaction degree of at least two turbine stages is of different values.

Abstract: A steam turbine has a high-pressure turbine section and a medium-pressure turbine section fluidically connected to the high-pressure turbine section. The high-pressure turbine section is a chamber configuration and the medium-pressure turbine section is a drum configuration. Alternatively, the high-pressure turbine section is a drum configuration and the medium-pressure turbine section is a chamber configuration. Alternatively, or additionally, the high-pressure turbine section is a double-flow configuration and the medium-pressure turbine section is a double-flow configuration.

Abstract: A thrust control system for use with a turbocompressor having gas bearings. More specifically, the system concerns an arrangement of gas bearings for use in a turbocompressor or other device where a large temperature difference between the turbine and the compressor housing could cause unacceptable performance of the turbocompressor thrust bearings if located in proximity of the turbine and compressor wheels. This danger is obviated in the system by relocating the gas thrust bearings so as to minimize the axial distance between them. This configuration affords the additional advantage that gasses of different composition may be separately used as a seal gas in cases where the process gas in the turbine and compressor are incompatible.

Abstract: The present invention contemplates an internally reinforced high-speed magnetic thrust disk. In one embodiment the internally reinforced composite thrust disk comprises a plurality of high strength fibers coupled together by a soft magnetic alloy. Further, in one aspect the disk having internally reinforced zones for controlling bore growth and counteracting forces associated with the reaction between the stator and the rotor of the electromagnetic thrust bearing system.

Abstract: This invention relates to rotary pumps adapted, but not exclusively, for use as artificial hearts or ventricular assist devices and, in particular, discloses in preferred forms a seal-less shaft-less pump featuring open or closed (shrouded) impeller blades with the edges of the blades used as hydrodynamic thrust bearing and with electromagnetic torque provided by the interaction between magnets embedded in the blades and a rotating current pattern generated in coils fixed relative to the pump housing.

Abstract: A flow channel and pressure equalizing sections introduce a fluid having substantially no angular momentum into a thrust balance chamber of a thrust balance device. The introduction of this fluid reduces the angular momentum of the fluid in the thrust balance chamber, facilitating the discharge of fluid out of the thrust balance chamber through a variable orifice. The thrust balance chamber exerts a variable pressure onto a rear surface of an impeller of a centrifugal pump. This pressure prevents significant displacement of the impeller during pump operation. The result is a centrifugal pump having good thrust balance properties regardless of flow rate and impeller speed.

Abstract: A low friction bearing comprises a first element having a first surface. A second element having a second surface is rotatable about a centerline relative to the first element. A flow passage extends radially outward between the first surface and the second surface. The first surface and the second surface are separated by a fluid flow. The two surfaces are complementary and positioned in close proximity. The bearing finds a preferred application in a fluid cooled turbine to create a high temperature, high efficiency turbine.

Abstract: A gas turbine engine includes a plurality of seal stages minimizing leakage of high pressure air from a high pressure cavity into a low pressure cavity. The plurality of seal stages includes an upstream seal stage, substantially adjacent to the high pressure cavity, and a downstream seal stage, substantially adjacent to the low pressure cavity. Each seal stage includes a seal plate and at least one seal. The downstream seal plate includes a plurality of bleeding holes for metering higher pressure air into the low pressure cavity, thereby balancing a pressure drop between the seal stages. Substantial equalization of the pressure drop among the seal stages reduces wear of the downstream seal and therefore, increases useful life an effectiveness thereof.

Abstract: A submersible centrifugal pump is claimed which includes an inner downthrust washer for receiving the downthrust load from the upward movement of the produced fluid, and an outer sealing washer, which is a non-load bearing washer, for allowing the repositioning of the impeller to prevent gaps that create recirculation.

Abstract: In a turbine construction which includes a rotor having at least one radial step formed therein, and at least one packing ring assembly mounted in a stationary turbine component and axially spanning the radial step, a thrust balancing arrangement for the rotor which includes an axial passage in the stationary component extending from a high pressure side of the stationary component and in fluid communication with an area adjacent the radial step on the rotor. A removable restrictor in the passage permits adjustment of the step thrust.

Abstract: A thrust bearing for a rotating member that is subject to axial forces causing movement in an axial direction of a rotating member. A sealing surface is positioned on at least a portion of the rotating member. A bearing is positioned adjacent the rotating member. A sealing face is positioned on the bearing. The sealing face is disposed to be in opposed relationship with the sealing surface on the rotating member. A bearing space is located between the sealing face and the sealing surface. A fluid reservoir is positioned in the bearing and is in communication with the bearing space. A passageway extends through the bearing to a volute adjacent the rotating member to supply a fluid to the fluid reservoir. A plurality of pockets are positioned on the sealing face of the bearing. The pockets are positioned to be in communication with the fluid reservoir. A plurality of wedge shaped depressions are positioned on the sealing face of the bearing.

Abstract: An integrated bearing system with journal and thrust bearings is incorporated in a single unit centrally pinned to the bearing housing and having integral thrust surface and journal surface lubrication grooves in combination with turbine and compressor wheel thrust surfaces. The bearing employs a first aperture substantially equidistant from the ends to engage the locating pin to prevent rotation of the bearing within the bearing case bore, while allowing the bearing to be free to symmetrically wobble within the bearing case bore.

Abstract: A submerged motor pump (4) has an auxiliary bearing assembly (19, 20) for supporting a rotatable main shaft (9) when the submerged motor pump is not in an operating condition or operates in a transient condition. The submerged motor pump includes a pump casing (6), at least one impeller (12), a motor (10,11), and a thrust balancing mechanism (15) for balancing thrust forces. The submerged motor pump further includes hydrostatic bearings (16, 17, 18) for supporting the main shaft at axially spaced locations by a pressurized fluid pumped by the submerged motor pump. The auxiliary bearing assembly has tapered support surfaces (FL, FU) for supporting the main shaft at the axially spaced locations.

Abstract: A thrust bearing assembly for a surface mounted centrifugal pump utilizes the pump liquid for lubrication of a thrust bearing and radial bearings. The thrust bearing mounts to the rearward end of the intake chamber. A communication passage extends between the thrust chamber and the intake chamber. A circulation tube leads from the intake chamber to the rearward end of the thrust chamber. A portion of the water being delivered to the intake chamber is diverted through the circulation tube, where it circulates through the thrust bearing and back to the intake of the pump. The shaft passes through the thrust chamber to an electrical motor. A mechanical seal seals the shaft at the rearward end of the thrust chamber.

Abstract: A high temperature pump is compact in size, reasonable in manufacturing cost and capable of stable pumping operation. The high-temperature motor pump includes a pump portion for pumping a liquid, a motor portion integrated with the pump portion for driving the same, and a rotatable shaft for transmitting rotation of the motor portion to the pump portion. A magnetic bearing is provided within the motor portion for supporting one end of the rotatable shaft by actively controlling a position thereof in a radial direction. A hydrostatic bearing is provided within the pump portion for supporting the other end of the rotational shaft in a radial direction by using a hydrostatic pressure of a portion of the liquid pumped by the pump portion.

Abstract: A gas turbine engine comprises turbine and compressor elements on a rotary shaft. The shaft is rotably mounted on preloaded axial thrust bearings. As it rotates in use the turbine and compressor elements create an axial thrust load on the bearings. According to the invention that axial thrust load is opposed by an electromagnetic coil which is energised to exert an axial force on the shaft in opposition to the axial thrust load and preferably completely balancing the axial thrust load. Bearing life is much extended.

Abstract: A system to hydrostatically augment the thrust load capacity of a bilateral compliant foil hydrodynamic fluid film thrust bearing for a turbomachine is disclosed. A plurality of channels and fixed orifices are provided in the bearing thrust plate to deliver and regulate compressor bleed air flow to the compressor side of the bilateral compliant foil hydrodynamic fluid film thrust bearing which includes additional channels and orifices to direct the bleed air against the bearing rotor thrust disk. After impinging on the rotor thrust disk, the bleed air flow exits the thrust bearing through a plurality of variable orifices comprised of the hydrodynamic thrust bearing elements which are controlled in their flow conductance by the axial position of the rotor thrust disk. The bleed air may then pass through the adjacent journal bearing which functions as a fixed orifice.

Abstract: A damping device is provided for damping the vibration of a rotatable shaft. The shaft has a shaft end portion and a detachable thrust collar. The thrust collar has an elongated portion which extends in the direction of the axis of the rotatable shaft and is hollow. Further, the elongated portion overhangs the shaft end portion. The damping device also has a stationary portion which is associated with the elongated portion of the thrust collar.

Abstract: A thrust load compensating system for a compliant foil hydrodynamic fluid film thrust bearing is disclosed. The system includes an end cap over the free end of a rotary machine shaft, a compliant foil hydrodynamic fluid film journal bearing located at the free end of the shaft, and a source of air whose pressure varies with the square of turbomachine speed. The compliant foil hydrodynamic fluid film journal bearing located at the free end of the shaft serves as a non-contacting rotary shaft seal and, together with the end cap and free end of the shaft forms a thrust piston chamber. The thrust load compensating system of the present invention can be utilized in high speed rotary machines that have a compressor wheel and a turbine wheel that generate large axial aerodynamic forces that increase with speed.

Abstract: A thrust bearing assembly for a surface mounted centrifugal pump utilizes the pump liquid for lubrication of a thrust bearing and radial bearings. The thrust bearing mounts to the rearward end of the intake chamber. A communication passage extends between the thrust chamber and the intake chamber. A circulation tube leads from the intake chamber to the rearward end of the thrust chamber. A portion of the water being delivered to the intake chamber is diverted through the circulation tube, where it circulates through the thrust bearing and back to the intake of the pump. The shaft passes through the thrust chamber to an electrical motor. A mechanical seal seals the shaft at the rearward end of the thrust chamber.

Abstract: A single stage centrifugal compressor is disclosed having a drive shaft with two thrust bearing collars disposed in a casing. The thrust collars are coupled to two sets of pads tiltingly engaged to two respective base plates. One or both of these base plates are coupled to the casing by a resilient member. This resilient member, by deflecting with the load allows the force applied to the thrust bearings to be balanced between the thrust bearings. It may be formed as two arcuate portions extending partially around the drive shaft or as a single ring. It may be formed as an annular portion with slots extending substantially radially outward from the rotational axis of the drive shaft outward to an outer surface facing away from the drive shaft, or may be made of two substantially parallel plates with an elastomeric layer sandwiched in between. The elastomeric layer may be either a single solid sheet or several elastomeric elements separated by gaps that allow the elastomer to expand outward when compressed.

Abstract: Fluid-flow machine having shaft (1) which is mounted in an axially fixed fashion, and a balancing piston (6) firmly arranged thereon. In order to reduce the leakage flow, the balancing piston (6) is partially replaced by a porting ring (12) which forms with the balancing piston a choke gap (11), through which radial flow occurs, and a cylindrical upstream throttle (13) through which axial flow occurs.

Abstract: A centrifugal pump adapted to be positioned in a wellbore in an inverted position to pump fluids downhole includes a pump housing, a rotatable shaft positioned within the pump housing, at least one pump stage positioned within the pump housing, with each pump stage comprising an impeller connected to and fixed relative to the shaft, and a stationary diffuser, and an upthrust bearing assembly positioned within the pump housing and comprising a rotatable thrust plate connected to the shaft and cooperating with a stationary thrust plate supported to the pump housing. The upthrust bearing assembly eliminates the need for a separate costly bearing assembly, such as would be included within an additional motor protector, when a centrifugal pump is positioned in a wellbore in an inverted position to pump fluids downhole.

Abstract: A pressurized bearing assembly for turbomachines like gas turbine engines wherein pressurized oil is used to apply an axial force to the outer bearing race of a ball bearing assembly. The force is transmitted through the race to the ball bearings and to the inner race of the bearing assembly, and is further transmitted, via the engine shaft, to the bearings of another, axially spaced apart bearing assembly. The force moves the balls in both assemblies into line-on-line running contact with their respective bearing races, and minimizes vibration in the assemblies.

Abstract: A condensing turbine includes a live-steam inlet, an exhaust-steam outlet and at least two seals for sealing off a turbine casing in the region of a turbine shaft carrying a turbine rotor. At least one of the seals is disposed on the live-steam side and one of the seals is disposed on the exhaust-steam side. The overall construction is substantially simplified by constructing at least one respective seal as a gas-lubricated mechanical surface seal on both the live-steam side and the exhaust-steam side. The outermost mechanical surface seals in each case on the live-steam side and the exhaust-steam side seal off separate seal spaces which are acted upon through a balancing line by an identical vacuum lying below the outer atmospheric pressure. These mechanical surface seals are constructed and fitted in such a way that a flow which is necessary for gas lubrication can occur through the mechanical surface seals from the outer atmosphere into the interior of the casing.

Abstract: A multistage centrifugal pump for increasing the pressure of a product fluid passing through it. The pump includes a casing, an impeller shaft mounted for rotation within the casing and a plurality of impellers mounted back-to-back on the impeller shaft. A canned magnetic radial bearing is mounted around the outboard end of the impeller shaft and a magnetic thrust bearing and a magnetic radial bearing are mounted around the drive end of the impeller shaft. The pump is free of any product fluid return line connecting the product fluid chambers at the drive and outboard ends of the shaft.

Abstract: A multi-stage centrifugal pump is described having a linear series of impellets mounted on a common impeller shaft, with axial thrusts imparted to the shaft by the impellets being balanced by a sealed high-pressure thrust bearing assembly secured to the pump casing. The pump is particularly suitable for using in pumping an abrasive fluid. A clean lubricating oil is supplied to the thrust bearing assembly at a pressure slightly greater than that of the abrasive pumped fluid, to ensure that the fluid that migrates across a mechanical seal interposed between the impeller assembly and the thrust bearing assembly is the lubricating oil, not the abrasive pumped fluid. High pressure differentials across a breakdown bushing involving the abrasive pumped fluid, and a resulting wear and erosion of pump components, thereby are avoided.

Abstract: In a turbo machine with magnetic bearings on both sides and dry gas seals for the rotor, the axial thrust acting upon the rotor and generated by the pressure difference between the pressure side and the suction side is compensated for in that a dry gas seal provided on the suction side and the end of the shaft are acted upon by a certain pressure, which generates a compensating axial thrust, so that the resultant axial thrust becomes as slight as possible. Advantageously, this pressure is regulated via the bearing gap of an axial magnetic bearing of the rotor such that the bearing gas assumes a predetermined value.

Abstract: A turbo compressor in which a rotor having impellers is supported by a magnetic bearing is constructed such that a control valve is provided in a thrust balancing line connecting a suction line of the compressor to a balancing chamber formed outside a balancing drum provided at one end side of a rotor. The control valve serves to regulate a rate at which a gas flows through the thrust balancing line, and is adapted to be controlled in relation to a load imposed upon the magnetic thrust bearing.

Abstract: A thrust control system for fluid handling rotary machines, such as turbo expanders equipped with a magnetic thrust bearing, includes a magnetic thrust control circuit for providing a thrust signal which is a measure of the magnitude and direction of the thrust force on the thrust bearing. The rotor and stator of the machine have generally axially opposed thrust areas separated by a thrust cavity. Valves are connected between the thrust cavity and high and low pressure fluid sources. A controller, responsive to the thrust signal, controls the valves to selectively conduct fluid between the cavity and the high and low pressure sources to increase or decrease the fluid pressure in the cavity to minimize variations of the thrust force from a preset value which could be zero, for example.

Abstract: An industrial gas turbine engine includes in serial flow relationship a first compressor, a second compressor, a combustor, a first turbine, and a second turbine. The first compressor and the second turbine are fixedly joined together by a first shaft, and a turbine rear frame having a hub is disposed downstream of the second turbine for rotatably supporting the first shaft. A balance piston is fixedly joined to the first shaft, and means for channeling a fluid first to the balance piston for balancing thrust force on the first shaft and then to the turbine rear frame for heating the hub are provided. The apparatus is effective for carrying out a method including channeling a fluid first to the balance piston for thrust balancing the first shaft and then channeling the fluid to the turbine rear frame for heating the frame hub.