Steam turbine exhaust diffuser

Abstract

An axial flow steam turbine includes an exhaust diffuser in the form of a volute for diffusing the exhaust steam and turning the exhaust steam from a generally axial flow direction to a generally radial direction. The volute exit may be at the bottom or to one side of the steam turbine. The volute and casing are independently mounted relative to one another on a foundation with a flexible joint therebetween.

1 . An axial flow steam turbine flow path comprising: 
 a rotor and a casing defining the axial steam flow path; and    an exhaust diffuser for the turbine including a volute for diffusing the exhaust steam and turning the exhaust steam from a generally axial flow direction to a generally transverse and tangential direction.    
   
   
       2 . A flow path according to  claim 1  wherein said volute has an axis generally parallel to an axis of the flow path.  
   
   
       3 . A flow path according to  claim 1  wherein said exhaust diffuser and said casing are independently mounted relative to one another on a foundation.  
   
   
       4 . A flow path according to  claim 1  including a flexible joint between said exhaust diffuser and said casing.  
   
   
       5 . A flow path according to  claim 1  wherein said volute has an axis generally parallel to an axis of the flow path, said volute terminating in an outlet facing in a downward, upward or transverse direction.  
   
   
       6 . A flow path according to  claim 1  wherein said volute has an axis generally parallel to an axis of the flow path, said exhaust diffuser and said casing being independently mounted relative to one another on a foundation.  
   
   
       7 . A flow path according to  claim 6  including a flexible joint between said exhaust diffuser and said casing.