Method for modifying a airfoil shroud and airfoil

Abstract

According to one aspect of the invention, a method is provided for modifying an airfoil shroud located at a tip of an airfoil of a airfoil, the airfoil shroud having a first end edge, a second end edge, a leading edge and a trailing edge. The method includes locating a reference location in the first end edge of the airfoil shroud, the reference location being proximate a seal rail extending circumferentially from the substantially horizontal surface and forming a relief cut in the airfoil shroud to remove the reference location, wherein a modifying of the airfoil shroud is complete following forming of the relief cut.

1 . A method for modifying an airfoil shroud located at a tip of a blade of an airfoil, the airfoil shroud having a first end edge, a second end edge, a leading edge and a trailing edge, the method comprising:
 locating a reference location in the first end edge of the airfoil shroud, the reference location being proximate a seal rail extending circumferentially from a radially outer surface of the airfoil shroud; and   forming a relief cut in the airfoil shroud to remove the reference location, wherein a modifying of the airfoil shroud is complete following forming of the relief cut.   
     
     
         2 . The method of  claim 1 , wherein locating the reference location comprises locating a reference location proximate a fillet of the seal rail. 
     
     
         3 . The method of  claim 1 , wherein no welding occurs during modifying of the airfoil shroud. 
     
     
         4 . The method of  claim 1 , wherein forming the relief cut comprises forming a recess of a selected geometry in the first end edge of the airfoil shroud. 
     
     
         5 . The method of  claim 4 , wherein forming the recess of the selected geometry comprises forming an arc-shaped recess. 
     
     
         6 . The method of  claim 1 , wherein forming the relief cut comprises machining the relief cut. 
     
     
         7 . The method of  claim 1 , comprising replacing the airfoil in a second stage of a turbine engine after forming the relief cut. 
     
     
         8 . A bucket comprising:
 an airfoil having an airfoil axis;   a shroud disposed at a tip of the airfoil, the shroud having a first end edge, a second end edge, a leading edge and a trailing edge;   a seal rail extending circumferentially from a radially outer surface of the shroud; and   a recess formed in the first end edge proximate the seal rail and a trailing edge of the airfoil.   
     
     
         9 . The bucket of  claim 8 , wherein the recess comprises a relief cut of a selected geometry. 
     
     
         10 . The bucket of  claim 9 , wherein the selected geometry comprises an arc-shaped recess. 
     
     
         11 . The bucket of  claim 10 , wherein the arc-shaped recess is formed by machining. 
     
     
         12 . The bucket of  claim 9 , wherein the relief cut is formed to remove a reference location located in the first end edge proximate a fillet of the seal rail. 
     
     
         13 . The bucket of  claim 12 , wherein the reference location is serviced without a welding operation. 
     
     
         14 . The bucket of  claim 8 , wherein the bucket is configured to be placed in a second stage of the turbine engine. 
     
     
         15 . A turbine engine comprising:
 a rotor;   bucket to be placed on the rotor, the bucket comprising:   an airfoil having an airfoil axis;   a shroud disposed at a tip of the airfoil, the shroud having a first end edge, a second end edge, a leading edge and a trailing edge;   a seal rail extending circumferentially from a radially outer surface of the shroud; and   a recess formed in the first end edge proximate the seal rail and a trailing edge of the airfoil.   
     
     
         16 . The turbine engine of  claim 15 , wherein the recess comprises an arc-shaped relief cut. 
     
     
         17 . The turbine engine of  claim 16 , wherein the arc-shaped relief cut is formed by machining. 
     
     
         18 . The turbine engine of  claim 16 , wherein the arc-shaped relief cut is formed to remove a reference location located in the first end edge proximate a fillet of the seal rail. 
     
     
         19 . The turbine engine of  claim 18 , wherein the reference location is serviced without a welding operation. 
     
     
         20 . The turbine engine of  claim 15 , wherein the bucket is located in a second stage of the turbine engine.