Steam turbine

Abstract

A steam turbine with an operating temperature of more than 650° C. includes a thermally highly-loaded housing (G) which is produced by a casting technique at least partially from a nickel-based alloy. Production of such a steam turbine is simplified by the housing (G) being divided into a multiplicity of smaller housing sections (G 1 , . . . , G 8 ; G 21 , G 22 , G 31 , G 32 ) which are interconnected and together form the housing (G).

1 . A steam turbine with an operating temperature of more than 650° C., the steam turbine defining an axis, which steam turbine comprises a thermally highly-loaded housing which is produced by a casting technique at least partially from a nickel-based alloy, wherein the housing is divided into a plurality of smaller housing sections which are interconnected and together form the housing to simplify production of the housing. 
   
   
       2 . The steam turbine as claimed in  claim 1 , wherein at least some of the plurality of housing sections are welded to each other to form the housing. 
   
   
       3 . The steam turbine as claimed in  claim 2 , wherein the welded housing sections are welded to each other in planes which are oriented perpendicularly, parallel, or both, to the direction of flow of the steam through the housing at the welded housing section. 
   
   
       4 . The steam turbine as claimed in  claim 1 , wherein the steam turbine is a medium-pressure steam turbine having an inner housing, and wherein said housing with a plurality of smaller housing sections is said inner housing of the medium-pressure steam turbine. 
   
   
       5 . The steam turbine as claimed in  claim 4 , wherein the inner housing is divided into at least two shell sections along a parting plane which lies parallel to the steam turbine axis, and further comprising:
 reinforcing elements configured and arranged to mechanical reinforce the inner housing.   
   
   
       6 . The steam turbine as claimed in  claim 5 , wherein the reinforcing elements comprise axially arranged shrink-rings which tightly encompass the housing. 
   
   
       7 . The steam turbine as claimed in  claim 1 , wherein the steam turbine is a medium-pressure steam turbine having an inlet, and further comprising:
 at least one valve unit arranged at the medium-pressure steam turbine steam inlet configured and arranged to control the steam feed to the medium-pressure steam turbine; and   wherein said housing, which is divided into a plurality of smaller housing sections, is the housing of the at least one valve unit.   
   
   
       8 . The steam turbine as claimed in  claim 7 , further comprising:
 two steam inlets opposite each other on the medium-pressure steam turbine;   two valve units, each associated with one of the two steam inlets, each of said two valve units comprising a housing; and   wherein the housings of the two valve units are each divided into a plurality of smaller housing sections.   
   
   
       9 . The steam turbine as claimed in  claim 7 , wherein each valve unit comprises a housing, a first valve, and a second valve, the first and second valves being connected in series in the direction of flow and are positioned together in the housing; and
 wherein the first valve comprises a stop valve and the second valve comprises a control valve.   
   
   
       10 . The steam turbine as claimed in  claim 9 , wherein:
 each valve unit housing comprises a spherical housing section for the first valve and the second valve; and   said spherical housing sections are each divided into a plurality of shell sections which are each interconnected by at least one weld seam which extends in the direction of flow.   
   
   
       11 . The steam turbine as claimed in  claim 10 , wherein:
 each valve unit housing comprises a steam feed line which leads to the first valve; and   each steam feed line is formed as a one-piece housing section and is connected to the first valve housing by a circumferential weld seam.   
   
   
       12 . The steam turbine as claimed in  claim 10 , wherein:
 each valve unit housing comprises a connecting port which projects from the second valve; and   each connecting port is formed as a one-piece housing section and is connected to the second valve housing section by a circumferential weld seam.   
   
   
       13 . The steam turbine as claimed in  claim 10 , further comprising:
 reinforcing elements configured and arranged to mechanically reinforce the housing, which tightly encompass the housing at different points.   
   
   
       14 . The steam turbine as claimed in  claim 13 , wherein the reinforcing elements comprise shrink-rings. 
   
   
       15 . The steam turbine as claimed in  claim 14 , wherein the shrink-rings are positioned in the region of the spherical housing sections. 
   
   
       16 . The steam turbine as claimed in  claim 10 , further comprising:
 double-walled housing constructions each having an inner section and an outer section, wherein each valve unit housing is the inner section of one of the double-walled housing constructions, and wherein each inner section is formed of a nickel-based alloy and each outer section is formed of a steel.   
   
   
       17 . The steam turbine as claimed in  claim 1 , wherein the steam turbine is a medium-pressure steam turbine, and further comprising:
 at least one valve unit arranged on the medium-pressure steam turbine configured and arranged to control the steam feed to the medium-pressure steam turbine, and wherein the at least one valve unit comprises at least two parallel-operating valves of the same type.   
   
   
       18 . The steam turbine as claimed in  claim 17 , wherein the at least two parallel-operating valves comprise control valves to which steam is fed separately, and downstream of which the steam from both of the at least two parallel-operating valves is merged. 
   
   
       19 . The steam turbine as claimed in  claim 17 , wherein the at least two parallel-operating valves each comprise a stop valve to which steam is separately fed, and further comprising:
 a third, control valve arranged downstream of the at least two stop valves in the direction of flow and at which the steam from the at least two stop valves is merged.   
   
   
       20 . The steam turbine as claimed in  claim 19 , further comprising:
 connecting lines connecting the at least two stop valves to the control valve;   a connecting port connecting the control valve to the steam turbine; and   wherein the connecting lines are oriented perpendicularly to the connecting port.   
   
   
       21 . The steam turbine as claimed in  claim 19 , further comprising:
 connecting lines connecting the at least two stop valves to the control valve;   a connecting port connecting the control valve to the steam turbine; and   wherein the connecting lines and the connecting port form a Y-configuration.   
   
   
       22 . The steam turbine as claimed in  19 , further comprising:
 connecting lines connecting the at least two stop valves to the control valve;   a connecting port connecting the control valve to the steam turbine; and   wherein the connecting lines and the connecting port form a fork-shaped configuration.