Turbomachine rotor blade milling machine system and method of field repairing a turbomachine rotor blade

Abstract

A turbomachine rotor blade milling machine system includes a fixture having a body including first and second opposing surfaces and a slot. The fixture is configured and disposed to connect with first and second rotor blade sections mounted in a rotor wheel. A mounting system includes at least one mounting element coupled to one of the first and second opposing surfaces of the body at the slot. A milling machine is coupled to the one of the first and second opposing surfaces through the at least one mounting element. The milling machine includes a cutter and is configured and disposed to form an opening extending axially through a dovetail portion of a third rotor blade section arranged between the first and second rotor blade sections.

What is claimed is: 
     
         1 . A turbomachine rotor blade milling machine system comprising:
 a fixture including a body having first and second opposing surfaces and a slot, the fixture being configured and disposed to connect with first and second rotor blade sections mounted in a rotor wheel;   a mounting system including at least one mounting element coupled to one of the first and second opposing surfaces of the body at the slot; and   a milling machine coupled to the one of the first and second opposing surfaces through the at least one mounting element, the milling machine including a cutter and being configured and disposed to form an opening extending axially through a dovetail portion of a third rotor blade section arranged between the first and second rotor blade sections.   
     
     
         2 . The turbomachine rotor blade milling machine system according to  claim 1 , wherein the body includes a mounting section having a first mounting member configured and disposed to align with the first rotor blade section and a second mounting member configured and disposed to align with the second rotor blade section. 
     
     
         3 . The turbomachine rotor blade milling machine system according to  claim 2 , wherein the body includes a guide section extending substantially perpendicularly from the mounting section, the slot extending through each of the mounting section and the guide section. 
     
     
         4 . The turbomachine rotor blade milling machine system according to  claim 1 , wherein the other of the first and second opposing surfaces of the body includes at least one radiused portion configured and disposed to cooperate with a surface of the rotor wheel. 
     
     
         5 . The turbomachine rotor blade milling machine system according to  claim 1 , further comprising: a milling machine guide member mounted to the body through the at least one mounting element. 
     
     
         6 . The turbomachine rotor blade milling machine system according to  claim 5 , wherein the milling machine guide member includes a first guide element fixedly mounted to the body and a second guide element shiftably mounted to the first guide element, the milling machine being coupled to the second guide element. 
     
     
         7 . The turbomachine rotor blade milling machine system according to  claim 6 , wherein the second guide element is mounted to the first guide element through a dovetail interface. 
     
     
         8 . The turbomachine rotor blade milling machine system according to  claim 1 , further comprising: a dummy dovetail member configured and disposed to be mounted in an empty dovetail slot of the rotor wheel, the dummy dovetail member providing an interface between the fixture and the rotor wheel. 
     
     
         9 . A method of repairing a turbomachine rotor blade, the method comprising:
 removing an airfoil portion of a first turbomachine rotor blade, a second turbomachine rotor blade and a third turbomachine rotor blade mounted to a rotor wheel;   aligning a slot formed in a fixture with a root portion of the airfoil portion removed from the second turbomachine rotor blade;   mounting the fixture to the first turbomachine rotor blade and the third turbomachine rotor blade with the root portion of the second turbomachine rotor blade aligned with the slot;   positioning a cutter of a milling machine in the slot;   securing the milling machine to the fixture; and   guiding the cutter through a dovetail portion of the second turbomachine rotor blade to perform a repair of a turbomachine.   
     
     
         10 . The method of  claim 9 , further comprising: removing any remaining portions of the second turbomachine rotor blade from the rotor wheel. 
     
     
         11 . The method of  claim 9 , further comprising: inserting a dummy dovetail member into a dovetail slot formed in the rotor wheel previously occupied by the second turbomachine rotor blade. 
     
     
         12 . The method of  claim 11 , further comprising: mounting the fixture to the dummy dovetail member and a fourth rotor blade with a root portion of the airfoil portion removed from the third turbomachine rotor blade being aligned with the slot. 
     
     
         13 . The method of  claim 9 , wherein removing the airfoil portion of the first turbomachine rotor blade, the second turbomachine rotor blade and the third turbomachine rotor blade mounted to a rotor wheel includes removing the airfoil portion from first, second, and third compressor rotor blades. 
     
     
         14 . The method of  claim 13 , wherein removing the airfoil portion of first, second and third compressor rotor blades includes removing the airfoil portion of first, second and third compressor blades provides on one of a first stage rotor wheel and a second stage rotor wheel. 
     
     
         15 . A turbomachine comprising:
 a compressor portion including at least one compressor rotor wheel having a plurality of compressor rotor blades;   a turbine portion including at least one turbine rotor wheel having a plurality of turbine rotor blades; and   a turbomachine rotor blade milling machine system mounted to one of the compressor rotor wheel and turbine rotor wheel, the turbomachine rotor blade milling machine system comprising:
 a fixture including a body having first and second opposing surfaces and a slot, the fixture being mounted to the one of the compressor rotor wheel and the turbine rotor wheel; 
 a mounting system including at least one mounting element coupled to one of the first and second opposing surfaces of the body at the slot; and 
 a milling machine coupled to the one of the first and second opposing surfaces through the mounting system, the milling machine including a cutter and being configured and disposed to form an opening extending axially through a dovetail portion of a corresponding one of the plurality of compressor rotor blades and the turbine rotor blades. 
   
     
     
         16 . The turbomachine according to  claim 15 , wherein the body is mounted to the a first stage compressor rotor wheel through first and second compressor rotor blade sections, the body includes a mounting section having a first mounting element configured and disposed to align with the first rotor blade section and a second mounting element configured and disposed to align with the second compressor rotor blade section. 
     
     
         17 . The turbomachine according to  claim 16 , wherein the body includes a guide section extending substantially perpendicularly from the mounting section, the slot extending through each of the mounting section and the guide section. 
     
     
         18 . The turbomachine according to  claim 15 , further comprising: a milling machine guide member mounted to the body through the at least one mounting element, the milling machine guide member including a first guide element fixedly mounted to the body and a second guide element shiftably mounted to the first guide element, the milling machine being coupled to the second guide element. 
     
     
         19 . The turbomachine according to  claim 18 , wherein the second guide element is mounted to the first guide element through a dovetail interface. 
     
     
         20 . The turbomachine according to  claim 16 , further comprising: a dummy dovetail member configured and disposed to be mounted in an empty dovetail slot of the one of the compressor rotor wheel and the turbine rotor wheel, the dummy dovetail member providing an interface between the fixture and the one of the compressor rotor wheel and the turbine rotor wheel.