Abstract: Compressor bodies, an accelerator and a main motor are disposed on a base, while an innercooler, an aftercooler an oil cooler and a coolant cooler are disposed perpendicular to the axial direction of the motor so that the directions, in which the tube nests of the gas coolers are drawn out, are made to be the same. A control panel having a maintenance display is mounted on a front panel composed of panel portions which are mounted pivotally around respective remote or opposite side ends. Portions to be inspected daily are disposed near the front panel and one side panel adjacent thereto.

Abstract: A controller of magnetic bearing controls the rotor speed with a reduced drive current while suppressing the rotor vibration. The controller implements the ABS control, N-cross control, N-straight control and FF control in proper combination in addition to the basic PID control. A computer in the controller determines the activation of each control in accordance with a predetermined table of control plan in response to the detected rotor speed.

Abstract: Compressor bodies, an accelerator and a main motor are disposed on a base, while an intercooler, an aftercooler, an oil cooler and a coolant cooler are disposed perpendicular to the axial direction of the motor so that the directions, in which the tube nests of the gas coolers are drawn out, are made to be the same. A control panel having a maintenance display is mounted on a front panel composed of panel portions which are mounted pivotally around respective remote or opposite side ends. Portions to be inspected daily are disposed near the front panel and one side panel adjacent thereto. The compressor bodies including rotors that have been coated with a melted and solidified substantially homogeneous and continuous layer of a tetrafluoroethylene-perfluoroalkylvinylether copolymer that is substantially devoid of pinholes.

Abstract: A single-shaft multi-stage centrifugal compressor has a multiplicity of impellers for compressing a main gas and an impeller for compressing an intermediate suction gas which are carried by the same impeller shaft. The suction pressure of the impeller constituting the final stage for the compression of the main gas is maintained higher than the suction pressure of the impeller for compressing the intermediate suction gas. With this arrangement, a part of the main gas of a pressure slightly higher than the intermediate suction gas is introduced into the shaft seals, and the shaft seals and drainers are protected from any corrosive and toxic components which may be contained by the intermediate suction gas.

Abstract: A head flange mounting device for mounting a head flange on a casing in a turbo-machine, such as a centrifugal compressor, is disclosed which includes a plurality of slide keyways formed on the inner surface of the casing and on the outer circumferential surface of the head flange in such a manner that each slide keyway formed on the casing and each slide keyway formed on the casing and each slide keyway formed on the head flange are in juxtaposed relation to form a pair of slide keyways. A slide key is held in each pair of slide keyways so as to keep the center axis of the head flange in alignment with the center axis of the casing at all times.