Volute Structure, Centrifugal Compressor and Refrigeration Equipment

Abstract

The present application discloses a volute structure, a centrifugal compressor and a refrigeration device. The volute structure comprises: a cabinet ( 8 ), a volute casing ( 1 ) and a backflow device ( 5 ); the volute casing ( 1 ) comprises an inner volute and an outer volute separately provided, a fluid flow passage being formed between the inner volute and outer volute, and the inner volute and backflow device ( 5 ) being disposed together. The present application increases the length of the first-stage diffuser, improving the diffusion effect of air entering the first-stage diffuser and thus enhancing the unit performance of the centrifugal compressor.

1 . A volute structure, comprising: a cabinet, a volute housing, and a backflow device;
 the volute housing comprising an inner volute and an outer volute which are separately provided, a fluid passage being formed between the inner volute and the outer volute; and   the inner volute being arranged with the backflow device.   
     
     
         2 . The volute structure according to  claim 1 , wherein the inner volute and the backflow device are casted integrally. 
     
     
         3 . The volute structure according to  claim 1 , wherein the outer volute and the cabinet are casted integrally. 
     
     
         4 . The volute structure according to  claim 1 , wherein a connection portion between the inner volute and the outer volute is rounded. 
     
     
         5 . The volute structure according to  claim 1 , wherein the volute structure further comprises a curve passage that is fixed on the backflow device. 
     
     
         6 . The volute structure according to  claim 5 , wherein the curve passage and the backflow device are casted integrally. 
     
     
         7 . A centrifugal compressor, comprising a volute structure having a cabinet, a volute housing, and a backflow device; the volute housing comprising an inner volute and an outer volute which are separately provided, a fluid passage being formed between the inner volute and the outer volute; and the inner volute being arranged with the backflow device. 
     
     
         8 . The volute structure according to  claim 7 , wherein the centrifugal compressor also comprises a housing, and the volute structure further comprises a one-stage diffuser; and
 wherein the housing, the cabinet, the one-stage diffuser, and the backflow device enclose a one-stage gas supply cavity.   
     
     
         9 . The volute structure according to  claim 7 , wherein the centrifugal compressor is a double-stage or multi-stage centrifugal compressor. 
     
     
         10 . A refrigerant device, comprising a centrifugal compressor having a volute structure having a cabinet, a volute housing, and a backflow device; the volute housing comprising an inner volute and an outer volute which are separately provided, a fluid passage being formed between the inner volute and the outer volute; and the inner volute being arranged with the backflow device.