The shaft seal arrangement for a rotating turbomachine shaft having a rotation axis, comprises a rotor part and a stationary part. A dry gas seal is further provided, in combination with a cooling fluid volume arranged for receiving a cooling fluid and in heat exchange relationship with the dry gas seal. A venting arrangement collectively vents exhaust cooling fluid and dry sealing gas from the shaft seal arrangement.

A sealing structure includes: an insertion hole formed in a sealing plate; a sealing ring provided in the insertion hole; a first rotating body provided to the shaft, at least a part of the first rotating body positioned inside the insertion hole; a second rotating body disposed at a position apart from the compressor impeller than the first rotating body and having a maximum outer diameter larger than a minimum inner diameter of the insertion hole; and an annular receiving groove formed by the first rotating body and the second rotating body and receiving an inner circumferential surface side of the sealing ring.

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 seal structure includes a rotary shaft that is provided inside a housing, a metal-made surrounding portion of the housing that surrounds the rotary shaft in a radial direction of the rotary shaft, and a resin-made seal member that faces an inner circumferential surface of the surrounding portion and rotates together with the rotary shaft.

A sealing device includes: a sealing body that seals a gap between a rotor and the sealing body; a fastening bolt that fixes the sealing body to a stator; and a bolt sealing part that seals a gap around the fastening bolt. The sealing body includes: a facing surface that faces a fixing surface of the stator facing in an axial direction; and a body through-hole that penetrates the sealing body and opens on the facing surface. The bolt sealing part is disposed in a gap between a head portion and the inner peripheral surface of the body through-hole, or between the fixing surface and the facing surface.

There is disclosed a compressor comprising a case comprising a discharging part provided one side and configured to discharge a refrigerant, the case defining a predetermined space for storing oil; a drive part comprising a rotor coupled to an inner circumferential surface of the case and having coils wound there around and configured to generate a rotation magnetic field, and a rotor mounted in the rotor and configured to be rotatable by the rotation magnetic field; a shaft extending in a state of being coupled to the rotor; a compression part lubricated by the oil in a state of being coupled to the shaft and configured to compress and discharge the refrigerant; and a sealing part extending from the stator towards the compression part and configured to induce the winding of the coil.

The centrifugal compressor includes an hermetic housing; a drive shaft (4); a first and a second compression stage (8, 9) configured to compress a refrigerant, the first and second compression stages (8, 9) respectively including a first and a second impeller (18, 19), the first and second impellers (18, 19) being connected to the drive shaft (4) and being arranged in a back-to-back configuration; a radial annular groove (27) formed between the back-sides (25, 26) of the first and second impellers (18, 19); an inter-stage sealing arrangement (35) provided between the first and second compressor stages (8, 9) and in the radial annular groove (27); a radial bearing arrangement configured to rotatably support the drive shaft (4); and a thrust bearing arrangement configured to limit an axial movement of the drive shaft (4) during operation. The diameter of the inter-stage sealing arrangement (35) is configured to minimize the amplitude of the axial load applying on the thrust bearing arrangement during operation of the centrifugal compressor (2).

A centrifugal compressor includes a low-speed shaft, an impeller, a speed increaser, a housing, a separation wall, a shaft insertion hole, a seal member, an oil pan, an oil supply passage, an oil return passage, and a pressure reduction passage. The impeller is integrally rotated with a high-speed shaft. The housing has therein an impeller chamber accommodating the impeller and a speed increaser chamber accommodating the speed increaser. The centrifugal compressor includes a bypass passage having a first end communicating with the speed increaser chamber and a second end communicating with the oil pan.

A bearing apparatus includes a cylindrical sleeve, a shaft rotatably inserted in the sleeve, lubricating oil arranged in a gap defined between an inner circumferential surface of the sleeve and an outer circumferential surface of the shaft, a seal member arranged at an axially upper end portion of the sleeve projecting from the sleeve, and an annular member fixed to an outer circumferential surface of the axially upper end portion of the shaft to rotate together with the shaft. The annular member includes a projecting portion projecting axially downward. The seal member and an axially lower end portion of the projecting portion overlap each other when viewed in at least one of the axial direction or a radial direction.

The compressor arrangement comprises a main compressor having a suction side, a delivery side, and at least one dry gas seal. The dry gas seal is fluidly coupled to a sealing gas feed circuit adapted to receive sealing gas from the delivery side of the main compressor and feed the sealing gas to the at least one dry gas seal. An auxiliary compressor unit is further provided, including a sealing gas inlet fluidly coupled to the sealing gas feed circuit, and a sealing gas outlet fluidly coupled to the sealing gas feed circuit and adapted to booster the sealing gas pressure in the sealing gas feed circuit. The auxiliary compressor unit is further adapted to receive a gas flow from the main compressor, for instance a primary vent from the dry gas seal for recovery purposes.