Repair of Aircraft Fan Blade

Abstract

Systems and methods for repairing hollow fan blades. The hollow fan blade has a concave portion and a convex portion secured together by a joint. An interior cavity of the hollow fan blade is charged with a vacuum. The method includes removing material from a damaged portion of the hollow fan blade and welding the damaged portion such that a temperature of the joint does not exceed a distortion temperature.

The disclosure claimed is: 
     
         1 . A method of repairing a hollow fan blade, the hollow fan blade including a first portion and a second portion secured together by a joint, an interior cavity of the hollow fan blade being charged with a vacuum, the method including:
 removing material from a damaged portion of a leading edge of the hollow fan blade; and   welding the damaged portion such that a temperature of the joint does not exceed a distortion temperature.   
     
     
         2 . The method of  claim 1 , further including arranging a thermocouple on at least one of the first portion and the second portion. 
     
     
         3 . The method of  claim 2 , further comprising monitoring a temperature of a portion of the hollow fan blade during the welding using the thermocouple. 
     
     
         4 . The method of  claim 1 , further comprising arranging a plurality of thermocouples on each of the first portion and the second portion. 
     
     
         5 . The method of  claim 4 , further comprising arranging each of the plurality of thermocouples using at least one item selected from the group consisting of spot welding and adhesive. 
     
     
         6 . The method of  claim 1 , further comprising securing the hollow fan blade within a purge box prior to the welding. 
     
     
         7 . The method of  claim 1 , further comprising arranging a gas pad on at least one of the first portion and the second portion for dispersing an inert gas during the welding. 
     
     
         8 . The method of  claim 1 , further comprising cooling the blade using a cooling system during the welding. 
     
     
         9 . The method of  claim 8 , wherein the cooling system includes at least one of a copper block and a water-cooled block. 
     
     
         10 . The method of  claim 1 , wherein the welding includes Tungsten Inert Gas (TIG) welding. 
     
     
         11 . The method of  claim 1 , wherein the interior cavity further includes a honeycomb structure. 
     
     
         12 . The method of  claim 1 , further comprising applying
 a finishing process after the welding.   
     
     
         13 . The method of  claim 1 , wherein the joint includes a braze joint. 
     
     
         14 . A system for repairing a leading edge of a hollow fan blade, the hollow fan blade including a first portion and a second portion secured together by a joint, an interior cavity of the hollow fan blade being charged with a vacuum, the system comprising:
 a purge box having a mount for securing the hollow fan blade; and   a temperature sensor configured for monitoring of a temperature of the hollow fan blade during welding.   
     
     
         15 . The system of  claim 14 , further comprising a cooling system configured for cooling the first portion and the second portion of the blade during the welding. 
     
     
         16 . The system of  claim 14 , further comprising at least one gas pad arranged on at least one of the first portion and the second portion for dispersing an inert gas during the welding. 
     
     
         17 . The system of  claim 14 , wherein the hollow fan blade further includes a honeycomb structure within the interior cavity. 
     
     
         18 . A method of repairing a hollow fan blade, the hollow fan blade including a concave portion and a convex portion secured together by a joint, an interior cavity of the hollow fan blade being charged with a vacuum, the method comprising:
 removing material from a damaged portion of the hollow fan blade; and   welding the damaged portion such that a temperature of the joint does not exceed a distortion temperature.   
     
     
         19 . The method of  claim 18 , further comprising monitoring a temperature of the joint during the welding using a temperature sensor. 
     
     
         20 . The method of  claim 18 , further comprising arranging at least one gas pad proximate the joint on at least one of the concave portion and the convex portion for dispersing an inert gas during the welding.