Pressure casing of a turbomachine

Abstract

The invention relates to a pressure casing, which includes a plurality of casing shells which are connected in a pressure-tight manner in a parting plane by means of a flange. The casing shells are pressed together with sealing effect in the parting plane in the region of the flange by means of at least one threaded bolt which extends in a through hole through the flange perpendicularly to the parting plane. Reduced temperature differences between the flange and the connecting bolts of the flanged joint are achieved by the at least one threaded bolt being charged with a heat transfer medium over a part of its length. The heat transfer medium is supplied via holes extending through the flange.

1 . A pressure casing of a turbomachine comprising at least two casing shells which are connected in a pressure-tight manner in a parting plane by means of a flange, wherein the casing shells are pressed together with sealing effect in the parting plane in the region of the flange by means of at least one threaded bolt which extends through a through hole in the flange perpendicularly to the parting plane, and wherein the at least one threaded bolt is charged by a heat transfer medium, in that at least one of feed holes or outlet holes for the heat transfer medium are passed through the flange. 
     
     
         2 . The pressure casing as claimed in  claim 1 , wherein one or more feed holes for the heat transfer medium start at a source for the heat transfer medium, extend through the flange and end in a lateral surface of the through hole. 
     
     
         3 . The pressure casing as claimed in  claim 1 , wherein one or more outlet holes for the heat transfer medium start at the through hole, extend through the flange and end in a volume of a relatively low pressure compared to the pressure of the source. 
     
     
         4 . The pressure casing as claimed in  claim 1 , further comprising an annular space is provided between the inner lateral surface of the through hole and the shaft of the threaded bolt, this annular space is sealed in a tight manner on its both longitudinal ends and this annular space is charged by the heat transfer medium. 
     
     
         5 . The pressure casing as claimed in  claim 4 , wherein at least one of the feed holes or the outlet holes are open to the annular space. 
     
     
         6 . The pressure casing as claimed in  claim 5 , wherein the at least one feed hole and the at least one outlet hole lead to opposite ends of the annular space. 
     
     
         7 . The pressure casing as claimed in  claim 1 , wherein at at least a portion of the passages for the heat transfer medium are arranged in the parting line of the flange. 
     
     
         8 . The pressure casing as claimed in  claim 1 , wherein the heat transfer medium is air. 
     
     
         9 . The pressure casing as claimed in  claim 1 , wherein the heat transfer medium is steam. 
     
     
         10 . The pressure casing as claimed in  claim 1 , wherein the source for the fresh heat transfer medium is a plenum or the flow channel of the turbomachine. 
     
     
         11 . The pressure casing as claimed in  claim 10 , wherein both the source of the fresh heat transfer medium and the volume for the exhausted heat transfer medium is the flow channel of the turbomachine 
     
     
         12 . The pressure casing as claimed in  claim 11 , wherein the turbomachine is a compressor. 
     
     
         13 . Pressure casing as claimed in  claim 1 , wherein the casing is an inner carrier of a gas turine.