Abstract: A coupling to attach an impeller of a compressor to a shaft of an electric motor. The coupling has a coupling body that is attached at a first of the ends thereof to the impeller and at the opposite second end, to the motor shaft. The coupling body has a deformable section between the first and second ends of the coupling body. The deformable section is configured such that under an unbalanced loading exerted against the coupling body upon a failure of the impeller, the deformable section will permanently deform without the ultimate strength of a material forming the coupling body being exceeded and prior to a permanent deformation of the shaft. In such manner, the electric motor is protected from damage upon a failure of the impeller.

Abstract: A compression train system and method for compressing air for an air separation unit is provided. The system includes at least one initial air compressor configured to receive and compress a flow of ambient pressure air and driven by a variable speed motor. The system further includes a plurality of downstream compressors or compression turbo-machines disposed in a series arrangement with the at least one initial compression stage. The desired flow rates to the compression system is controlled by adjusting the speed of the variable speed motor and the position of inlet guide vanes to increase or decrease the flow rate of the ambient pressure air and keep the speed of the variable speed motor above or below a restricted speed zone.

Abstract: A method and apparatus for producing and controlling flow rate of a compressed gas produced by a compression system having one or more stages of compression formed by a centrifugal compressor or compressors, inlet guide vanes to control flow through the compression stage or stages and an electric motor directly coupled to the stage or stages having a restricted speed zone within which vibrational modes can damage the electric motor. A desired flow rate is obtained by speed adjustment alone and with the inlet guide vanes positioned at 0° when the speed will lie above or below the restricted speed zone. Where a desired flow rate would require extended operation of the electric motor at a speed within the restricted speed zone, the speed is set to the uppermost level of the restricted speed zone and the desired flow rate is obtained through appropriate positioning of the inlet guide vanes.

Abstract: The present invention provides a method and apparatus of inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event in which a thrust bearing is biased with a biasing force to increase the thrust bearing overload margin between the capacity of thrust bearing to absorb axial forces and the greatest force produced during the surge event. This biasing force can be produced by appropriately sizing the high pressure seal on the side of the impeller opposite to the inlet of a compressor of the compression system so that the back disk force produced in the high pressure region of the high pressure seal and the low pressure region located inwardly of the high pressure region creates the desired bias force value and direction.

Abstract: A coupling to attach an impeller of a compressor to a shaft of an electric motor. The coupling has a coupling body that is attached at a first of the ends thereof to the impeller and at the opposite second end, to the motor shaft. The coupling body has a deformable section between the first and second ends of the coupling body. The deformable section is configured such that under an unbalanced loading exerted against the coupling body upon a failure of the impeller, the deformable section will permanently deform without the ultimate strength of a material forming the coupling body being exceeded and prior to a permanent deformation of the shaft. In such manner, the electric motor is protected from damage upon a failure of the impeller.

Abstract: The present invention provides a method and apparatus of inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event in which a thrust bearing is biased with a biasing force to increase the thrust bearing overload margin between the capacity of thrust bearing to absorb axial forces and the greatest force produced during the surge event. This biasing force can be produced by appropriately sizing the high pressure seal on the side of the impeller opposite to the inlet of a compressor of the compression system so that the back disk force produced in the high pressure region of the high pressure seal and the low pressure region located inwardly of the high pressure region creates the desired bias force value and direction.

Abstract: A method and apparatus for producing and controlling flow rate of a compressed gas produced by a compression system having one or more stages of compression formed by a centrifugal compressor or compressors, inlet guide vanes to control flow through the compression stage or stages and an electric motor directly coupled to the stage or stages having a restricted speed zone within which vibrational modes can damage the electric motor. A desired flow rate is obtained by speed adjustment alone and with the inlet guide vanes positioned at 0° when the speed will lie above or below the restricted speed zone. Where a desired flow rate would require extended operation of the electric motor at a speed within the restricted speed zone, the speed is set to the uppermost level of the restricted speed zone and the desired flow rate is obtained through appropriate positioning of the inlet guide vanes.

Abstract: The present invention provides a method and apparatus of inhibiting a thrust bearing capacity of a compression system from being exceeded during a surge event in which a thrust bearing is biased with a biasing force to increase the thrust bearing overload margin between the capacity of thrust bearing to absorb axial forces and the greatest force produced during the surge event. This biasing force can be produced by appropriately sizing the high pressure seal on the side of the impeller opposite to the inlet of a compressor of the compression system so that the back disk force produced in the high pressure region of the high pressure seal and the low pressure region located inwardly of the high pressure region creates the desired bias force value and direction.

Abstract: A fluid impeller blade with lowered stress and increased useful life has an edge extending from the hub of the blade and forming, in part, a boundary for axial fluid flow. The edge, at least at its extremity, is spaced axially into the blade, at an angle of about 0.5.degree. to about 20.degree. from the radial line through the edge at the hub of the blade, whereby the mass of blade material exerting centrifugal force on the edge at the blade hub during rotation of the impeller is reduced.