Multi-impeller centrifugal compressor

The invention discloses a multi-impeller centrifugal compressor and relates to the technical field of the structural design of centrifugal compressors. A plurality of impellers are arranged on a spindle; the spindle comprises a first half spindle, a second half spindle and a connecting rod, wherein the first half spindle and the second half spindle are detachably fixedly connected with the two ends of the connecting rod; a first through hole penetrates through the second half spindle; a heating hole is formed along the central axis of the connecting rod, is coaxial with the first through holeand has the same pore diameter as the first through hole; the impellers are sequentially arranged on the connecting rod; a positioning seam allowance is formed between each of the impellers and the first half spindle, between each of the impellers and the second half spindle and between every two adjacent impellers; and every two adjacent impellers are in key limiting connection. According to themulti-impeller centrifugal