Blade for a gas turbine and casting technique method for producing same

Abstract

A blade for a gas turbine has a leading edge and a trailing edge, and an interior cavity, which is delimited by internal surfaces, for guiding cooling air therethrough. A multiplicity of turbulators or pins, which are formed on the wall, are arranged in a distributed manner in the region of the trailing edge and project from the internal surfaces into the cavity, to improve the transfer of heat between the wall of the blade and the cooling air. An improvement of the internal cooling is achieved by the turbulators or pins extending into the cavity in a direction which can be freely selected within an angular range.

What is claimed is: 
     
         1 . A method for producing a blade for a gas turbine by a casting technique, the blade having a leading edge and a trailing edge, and an interior cavity, which is delimited by internal surfaces, for guiding cooling air therethrough, wherein for improving the transfer of heat between the wall of the blade and the cooling air, a multiplicity of members, which are formed on the wall to improve cooling, are arranged in a distributed manner in the region of the trailing edge and project from the internal surfaces into the cavity, the members extending into the cavity in a direction which can be freely selected within an angular range, the method comprising:
 providing a core mold for forming a casting core which keeps the cavity of the blade free;   producing the casting core by means of the core mold;   removing the casting core from the core mold; and   casting the blade by the casting core, wherein:   the provided core mold comprises two mold halves, which during demolding are drawn apart in a first direction;   at least one mold insert, which is provided for forming the members, is arranged in the mold halves in the trailing edge region, and   in the removing of the casting core from the core mold, after the parting of the mold halves in the first direction, the at least one mold insert is withdrawn from the formed casting core in a second direction which differs from the first direction.   
     
     
         2 . The method as claimed in  claim 1 , wherein the second direction is perpendicular to the internal surface which is associated with the members. 
     
     
         3 . The method as claimed in  claim 2 , wherein a plurality of mold inserts are arranged in the mold halves and during demolding are withdrawn from the formed casting core in different directions which differ from the first direction.