An arrangement for compensating the axial thrust of a fluid-flow machine is provided. A load-relieving element is non-rotatably connected to a shaft. A flow-restrict gap is formed by the load-relieving element and a counter-element secured to a housing of the fluid-flow machine. The counter-element is provided with a device for maintaining the distance between the load-relieving element and the counter-element. The device includes at least one force-generating element that generates a force that acts in opposition to the axial thrust in order to avoid component contact.

The turbomachine comprises a stationary casing with a rotating member configured to rotate about a rotation axis in the stationary casing. The turbomachine further includes a rotating balance drum, arranged for co-rotation with the rotating member. A stationary sleeve is arranged in a fixed relationship with the stationary casing and surrounds the balance drum. The stationary sleeve comprises a plurality of consecutively arranged sleeve sections. A fluid channel is defined by an outer surface of the balance drum and an inner surface of the stationary sleeve. Between at least one pair of sequentially arranged upstream sleeve section and downstream sleeve section an annular chamber is provided, fluidly coupled to the fluid channel. Shunt holes are arranged on the upstream sleeve section, each shunt hole having a shunt hole inlet on an inner surface of the upstream sleeve section, and a shunt hole outlet in the annular chamber.

A centrifugal compressor includes a rotation shaft, an impeller, a housing including a first chamber, a second chamber of which pressure is lower than the first chamber, and a partition wall that partitions the first chamber and the second chamber and includes a through hole through which the rotation shaft is inserted, and a seal member arranged in the housing. The seal member includes a gas seal and a support. When the rotation shaft is rotating, the gas seal surrounds an outer circumferential surface of the rotation shaft in a non-contact state in which dynamic pressure forms a gap between the gas seal and the outer circumferential surface of the rotation shaft. The support supports the gas seal in a state in which the gas seal is movable in a direction intersecting an axial direction of the rotation shaft.

The use of externally-pressurized porous media in shaft sealing for turbomachinery is provided for single seals, tandem seals, double-opposed seals, and a ventless seal. These arrangements provide for significant benefits, such as the following: (a) external pressurization allows frozen seal faces to lift open before rotation, (b) pressure is distributed uniformly across the seal face, as opposed to allowing leakage to pass over it, (c) low flow rates of injected gas are possible, (d) the seal faces are self-defending due to the uniform pressure in the gap, and (e) complete elimination of venting process gas is possible. By employing externally-pressurized porous media sealing, a drastic simplification of seal design, as well as gas treatment and seal panel design, is possible.

A turbo compressor is provided that may include an impeller housing having an impeller accommodation space, an inlet formed at a first side of the impeller accommodation space, and an outlet formed at a second side of the impeller accommodation space that communicates with the inlet; an impeller accommodated in the impeller accommodation space of the impeller housing, rotated together with a rotary shaft by being coupled to the rotary shaft, and configured to centrifugally-compress a fluid suctioned through the inlet of the impeller housing and discharge the compressed fluid outside of the impeller housing through the outlet; a back pressure space formed between a rear surface of the impeller and the impeller housing; a back pressure passage connected between the outlet of the impeller housing and the back pressure space; and a back pressure control valve installed between the back pressure passage and the back pressure space, and configured to selectively open and close a region therebetween.

A balance piston seal assembly for a balance piston of a compressor is provided. The balance piston seal assembly may include a balance piston seal, a stationary support, and a gripping assembly disposed between the balance piston seal and the stationary support. The balance piston seal may be configured to be disposed about the balance piston such that an inner radial surface of the balance piston seal and an outer radial surface of the balance piston define a radial clearance therebetween. The stationary support may be configured to be coupled or integral with a casing of the compressor. The gripping assembly may be configured to secure the balance piston seal with the stationary support and to maintain concentricity between the balance piston seal and the balance piston during thermal radial expansion of the balance piston seal relative to the balance piston.

A rotating machine including a rotor operable to rotate about a centerline axis and subjected to axial thrust loads along the centerline axis during operation; a balance piston engaged with the rotor; a stator positioned around the balance piston and the rotor wherein a fluid passageway extends between the internal face of the stator and the external face of the balance piston; the fluid passageway including at least one cavity. A balance piston for a rotating machine including at least two segments arranged with a shift in diameter between each other.

A compressor for a motor-compressor set, comprising, on a rotating shaft, a balancing piston, a set of bladed wheels, a rear cavity of the piston adjacent to the balancing piston on a side opposite to the set of bladed wheels, a regulation valve suitable for coupling the rear cavity to the input of the set of bladed wheels, a suction pressure chamber coupled to the input of the set of bladed wheels, the rear cavity being arranged between the balancing piston and the suction pressure chamber. The compressor comprises a discharge pressure chamber arranged between the rear cavity of the piston and the suction pressure chamber, the discharge pressure chamber being coupled via a discharge line to a discharge area between the set of bladed wheels and the balancing piston.

A balancing and sealing piston system for an integrated motor compressor is described. The system comprises a balancing piston designed to be mounted on a shaft of a motor compressor to compensate for the differential pressure applied to the impellers of the compression section of the motor compressor, and a sealing device surrounding the balancing piston and designed to be mounted on a case of the motor compressor to seal part of the compression section. The system further comprises a gas extraction port, the axial position of which is determined such that the pressure value of extracted gas is equal to a predetermined value that is less than the value of the discharge pressure.

An apparatus and method for providing a pressurized air supply to a balance piston assembly to balance an axial load on a gas turbine engine compressor. The pressurized air supply can be supplied by mixing valve mixing a primary and secondary pressure bleed air supply relative to feedback received from the balance piston assembly to maintain a predetermined pressure at the balance piston assembly.