MULTISTAGE CENTRIFUGAL COMPRESSOR

A multistage centrifugal compressor is described. The compressor comprises a casing and a shaft rotatingly supported in the casing by at least a first bearing and a second bearing. At least one in-between-bearing impeller is mounted on the shaft, between the first bearing and the second bearing. An overhung impeller is mounted at one end of the shaft. A first diaphragm arrangement is further located in the casing. The first diaphragm arrangement comprises return a channel assembly with a plurality of stationary return channel blades defining a plurality of return vanes for redirecting compressed gas from an exit location of the overhung impeller to an inlet location of the in-between-bearings impeller. The first diaphragm arrangement houses one of the first bearing and second bearing.