Method for producing a turbine rotor

Abstract

A method of producing a turbine rotor, in particular a steam turbine rotor, is provided. A forged and machined existing steam turbine rotor having partially larger dimensions as dimensions of an intended rotor is provided. The form of the existing rotor is compared with the form of the intended rotor and a position of the intended rotor within the existing rotor is chosen. Material is applied by build-up welding on portions of the existing rotor where not enough material is present for machining the intended rotor at the chosen position. The intended rotor is produced at the chosen position by machining the existing rotor.

1 . Method for producing a turbine rotor comprising:
 a) providing at least one forged and machined existing steam turbine rotor having partially larger dimensions as dimensions of an intended rotor to be produced;   b) comparing the form of said at least one existing rotor with the form of the intended rotor and choosing a position of the intended rotor within said at least one existing rotor;   c) applying material by build-up welding on portions of said at least one existing rotor, where not enough material is present for machining the intended rotor at the chosen position; and   d) producing the intended rotor at the chosen position by machining the existing rotor.   
     
     
         2 . Method according to  claim 1 , wherein a choice of the position of the intended rotor within said at least one existing rotor in step b) is made taking into consideration production-orientated aspects, in particular the amount of material to be applied in step c) and/or the amount of material to be machined in step d). 
     
     
         3 . Method according to  claim 1 , wherein the machining in step d) is performed by means of turning and/or milling and/or grinding. 
     
     
         4 . Method according to  claim 1 , wherein at least two forged and machined existing steam turbine rotors are provided and joined to each other in step a). 
     
     
         5 . Method according to  claim 4 , wherein said at least two existing rotors are joined to each other by welding. 
     
     
         6 . Method according to  claim 4 , wherein one or both of said at least two forged and machined existing steam turbine rotors are shortened prior to their joining. 
     
     
         7 . Method according to  claim 5 , wherein one or both of said at least two forged and machined existing steam turbine rotors are shortened prior to their joining.