A method and apparatus using a cooler to selectively cool P3 air directed into an impeller rear cavity of a gas turbine engine during engine high power levels, may include connection of the cooler to a low pressure compressor bleed-off valve apparatus that is modulated to be closed during engine high power levels to create a pressure differential over the bleed-off valve apparatus, to drive a stream of low pressure compressor air as a cooling work fluid under such pressure differential to selectively flow through the cooler.

A magnetic bearing centrifugal compressor includes a magnetic bearing spindle having a thrust disk, front and rear axial bearings, an impeller and at least one labyrinth seal. The front and the rear axial bearings are disposed individually to opposing sides of the thrust disk. First and second clearances exist axially between the rear and front axial bearings, respectively, and the thrust disk. The impeller connects a front end of the magnetic bearing spindle. The labyrinth seal pairs the magnetic bearing spindle into an oblique arrangement with respect to the axial direction, and each the labyrinth seal is spaced from the magnetic bearing spindle or the impeller by a labyrinth-seal clearance. By controlling the thrust disk axially, a clearance ratio of the first clearance to the second clearance can be varied to adjust the labyrinth-seal clearance. In addition, a magnetic bearing centrifugal compressor controlling method is also provided.

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 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 balance piston seal assembly may also include a plurality of heaters in thermal communication with the balance piston seal and configured to heat and thermally expand the balance piston seal and thereby increase a radial length of the radial clearance.

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.

An axial thrust balancing mechanism for a rotating shaft apparatus such as a rotary pump provides self-regulating thrust compensation while avoiding contact and wear between rotating and static elements. A rotor fixed to the shaft includes a cylindrical male section proximal to but not extending within a cylindrical female section of a non-rotating stator, such that a gap formed therebetween is varied in width by shaft displacements caused by axial thrusts. Pressurized fluid within the female section applies a thrust-compensating force to the rotor that is controlled by the gap size. The female section is larger in diameter than the male section, thereby preventing any contact therebetween. The disclosed mechanism can be combined with a thrust-compensating drum so as to reduce the thrust to a residual level that can be regulated. The rotor and stator can be stepwise varied to provide a plurality of gaps and intermediate chambers therebetween.

A multistage centrifugal pump (1) has impellers (9) arranged on a common shaft (8), which is rotatably arranged within a pump casing (2-4). One end of the shaft (8) is led out of the casing (2-4) for connection to a drive motor and another shaft end (15) is rotatably mounted in the pump casing (2-4). The shaft end (15) which is mounted within the pump casing (2-4) is subjected to a counter-force which is produced by way of pressure subjection via a conduit connection to a delivery side of the pump. An axial seal (11) is provided on the shaft end (15) arranged within the pump casing (2-4). The rotating part of the axial seal is led on the shaft end and the non-rotating part is led, axially movably, within the pump casing (2-4). A sealing arrangement is provided between the pump casing and the axially movably mounted part.

An apparatus for adjusting an axial thrust force acting on a rotor of an integrally geared compressor (IGC) is provided. In the present disclosure, the axial thrust force acting on the rotor of the IGC may be adjusted in two opposite directions by tandem seals having different effective sealing diameters, and a thrust force generated in compressors located at both sides of a gear may be effectively offset. Furthermore, since a thrust load acting on the rotor of the IGC is offset, an operating pressure level at which the IGC operates may be increased.

A rotating machine includes: a rotary shaft that is configured to rotate about a center axis; an impeller that is fixed to the rotary shaft and that is configured to compress a working fluid by integrally rotating with the rotary shaft; a casing that covers the rotary shaft; a first seal portion that is disposed at a position away from the impeller in a center axis direction of the rotary shaft and that is configured to seal a portion between the rotary shaft and the casing with a seal gas; a second seal portion that is disposed between the impeller and the first seal portion and that is configured to seal a portion between the rotary shaft and the casing; and a gas supply path through which the seal gas is introduced into the first seal portion.

A multistage pump for installation on a sea ground includes a common housing, a pump unit arranged in the common housing, a drive unit arranged in the common housing, and a coupling. The common housing includes a pump inlet and a pump outlet, the pump unit including a plurality of impellers to convey a compressible fluid from the pump inlet to the pump outlet, and a pump shaft, on which each impeller is mounted, each impeller being a radial or semi-axial impeller. The drive unit includes a drive shaft to drive the pump shaft, and an electric motor configured to rotate the drive shaft about an axial direction. The coupling couples the drive shaft to the pump shaft. The pump unit conveys the fluid in a dense phase at the pump outlet, and at least two impellers of the plurality of impellers have a different specific speed.