Method and device for polishing the surface of a gas turbine blade

Abstract

The invention relates to a method and device for polishing the surface of a gas turbine blade. According to the invention, a metallic anticorrosive layer is polished by using a stream of dry ice whereby preventing the surface from becoming contaminated and obtaining cost advantages.

1 - 10 . (canceled)  
     
     
         11 . A process for removing ceramic material from the surface of a gas turbine component, comprising: 
 compressing air;    drying the compressed air;    cooling the compressed air;    feeding the dried cooled compressed air to a dry ice supply device;    feeding dry ice to the dry ice supply device;    releasing a mixture of the compressed air and the dry ice towards the surface to remove from the ceramic material from the surface by the impinging dry ice particles.    
     
     
         12 . The process as claimed in  claim 11 , wherein the dry ice particles are fed to the compressed air stream by a star feeder.  
     
     
         13 . The process as claimed in  claim 11 , wherein the air is compressed to a pressure level of 3 to 12 bar.  
     
     
         14 . The process as claimed in  claim 11 , wherein a compensation vessel is used to stabilize a constant mass flow.  
     
     
         15 . The process as claimed in  claim 11 , wherein the ceramic material comprises zirconium dioxide.  
     
     
         16 . The process as claimed in  claim 11 , wherein the surface is smoothed by the removal of the ceramic material.  
     
     
         17 . The process as claimed in  claim 16 , wherein a predetermined maximum roughness of the surface is set by the removal of the ceramic material.  
     
     
         18 . The process as claimed in  claim 11 , wherein a cooling passage that extends through the surface having a production-related burr formed at least in part in an opening region of the cooling passage is removed by the dry ice particles.  
     
     
         19 . The process as claimed in  claim 18 , wherein the cooling passage is formed by a laser beam.  
     
     
         20 . The process as claimed in  claim 17 , wherein a multi-axis manipulation device for moving the dry ice jet relative to the gas turbine blade or vane is used to remove the ceramic material and achieve the predetermined maximum roughness.  
     
     
         21 . The process as claimed in  claim 11 , wherein the dry ice jet exits a nozzle at a pressure of from 10 bar to 30 bar.  
     
     
         22 . The process as claimed in  claim 11 , wherein the ceramic material is completely removed by the dry ice particles.  
     
     
         23 . The process as claimed in  claim 11 , wherein the dry ice is provided in pellet form.  
     
     
         24 . The process as claimed in  claim 11 , wherein the mixture of compressed air and dry ice pellets is released towards the surface at near the speed of sound.  
     
     
         25 . The process as claimed in  claim 11 , wherein the mixture of compressed air and dry ice is passed over the surface a plurality of times.  
     
     
         26 . An apparatus for removing ceramic material from the surface of a gas turbine component, comprising: 
 a gas turbine component holder;    a compressor for compressing air;    a dryer for drying the compressed air;    a cooler for cooling the compressed air;    a dry ice supply device to receive the dried cooled compressed air;    a dry ice emitter for emitting a stream of dry ice within the compressed air; and    a multi-axis manipulation device for moving the dry ice jet relative to the gas turbine component.    
     
     
         27 . The apparatus as claimed in  claim 26 , wherein the gas turbine component is a blade or vane.  
     
     
         28 . The apparatus as claimed in  claim 26 , wherein the air is compressed to a pressure level from 3 to 12 bar.  
     
     
         29 . The apparatus as claimed in  claim 26 , wherein the surface is smoothed by the removal of the ceramic material.  
     
     
         30 . The apparatus as claimed in  claim 29 , wherein a predetermined maximum roughness of the surface is set by the removal of the ceramic material.  
     
     
         31 . The apparatus as claimed in  claim 26 , wherein a cooling passage that extends through the surface having a production-related burr is formed at least in part in an opening region of the cooling passage is removed by the dry ice jet.  
     
     
         32 . The apparatus as claimed in  claim 31 , wherein the cooling passage is formed by a laser beam.  
     
     
         33 . The apparatus as claimed in  claim 30 , wherein the multi-axis manipulation device removes the ceramic material from the surface and achieves the predetermined maximum roughness.  
     
     
         34 . The apparatus as claimed in  claim 26 , wherein the dry ice jet exits the supply device with an initial pressure of from 10 bar to 30 bar.  
     
     
         35 . The apparatus as claimed in  claim 26 , wherein the ceramic material is completely removed by the dry ice jet.  
     
     
         36 . The apparatus as claimed in  claim 26 , wherein the dry ice is provided in pellet supply form.  
     
     
         37 . The apparatus as claimed in  claim 26 , wherein the mixture of compressed air and dry ice pellets is released towards the surface at near the speed of sound.  
     
     
         38 . The apparatus as claimed in  claim 26 , wherein the mixture of compressed air and dry ice pellets is passed over the surface a plurality of times.