Method for manufacturing aircraft engine cases with bosses

Abstract

A method of manufacturing turbine engine casings having at least one boss includes, in one exemplary embodiment, forming an engine casing having an outer wall, machining a tapered opening through the casing outer wall, and machining a tapered portion in a metal plug where the tapered portion is sized to mate with the tapered opening in the casing outer wall. The method also includes inserting the metal plug into the tapered opening in the casing outer wall, and welding the metal plug to the casing.

1 . A method of manufacturing turbine engine casings having at least one boss, said method comprising: 
 forming an engine casing having an outer wall;    machining a tapered opening through the casing outer wall;    machining a tapered portion in a metal plug, the tapered portion sized to mate with the tapered opening in the casing outer wall;    inserting the metal plug into the tapered opening in the casing outer wall; and    welding the metal plug to the casing.    
   
   
       2 . A method in accordance with  claim 1  wherein the metal plug comprises a first portion adjacent the tapered portion, said inserting the metal plug comprises inserting the metal plug into the tapered opening in the casing outer wall so that the first portion extends beyond an outer surface of the casing outer wall.  
   
   
       3 . A method in accordance with  claim 2  wherein the metal plug comprises a second portion adjacent the tapered portion, said inserting the metal plug comprises inserting the metal plug into the tapered opening in the casing outer wall so that the second portion extends beyond an inner surface of the casing outer wall.  
   
   
       4 . A method in accordance with  claim 1  further comprising machining the metal plug to form a boss on the casing outer wall.  
   
   
       5 . A method in accordance with  claim 4  wherein the metal plug comprises a contoured shape that mirrors a predetermined shape of the boss, said machining the metal plug comprises machining the contoured shaped metal plug to the predetermined shape of the boss.  
   
   
       6 . A method in accordance with  claim 1  wherein welding the metal plug to the casing comprises inertia welding the tapered portion of the metal plug to the casing outer wall.  
   
   
       7 . A method of manufacturing turbine engine casings having at least one boss, said method comprising: 
 forging an engine casing having an outer wall;    machining a tapered opening through the casing outer wall;    machining a tapered portion in a metal plug, the tapered portion sized to mate with the tapered opening in the casing outer wall;    inserting the metal plug into the tapered opening in the casing outer wall;    welding the metal plug to the casing; and    machining the metal plug and at least a portion of the engine casing forging to form a boss on the casing outer wall.    
   
   
       8 . A method in accordance with  claim 7  wherein the metal plug comprises a first portion adjacent the tapered portion, said inserting the metal plug comprises inserting the metal plug into the tapered opening in the casing outer wall so that the first portion extends beyond an outer surface of the casing outer wall.  
   
   
       9 . A method in accordance with  claim 8  wherein the metal plug comprises a second portion adjacent the tapered portion, said inserting the metal plug comprises inserting the metal plug into the tapered opening in the casing outer wall so that the second portion extends beyond an inner surface of the casing outer wall.  
   
   
       10 . A method in accordance with  claim 7  wherein the metal plug comprises a contoured shape that mirrors a predetermined shape of the boss, said machining the metal plug comprises machining the contoured shaped metal plug to the predetermined shape of the boss.  
   
   
       11 . A method in accordance with  claim 7  wherein welding the metal plug to the casing comprises inertia welding the tapered portion of the metal plug to the casing outer wall.  
   
   
       12 . A turbine engine casing comprising: 
 an outer wall having a tapered opening extending therethrough; and    a metal plug having a tapered portion located at least partially in said tapered opening, said tapered portion of said metal plug mating with a side wall of said tapered opening in said outer wall.    
   
   
       13 . A turbine engine casing in accordance with  claim 12  wherein said metal plug is welded to said outer wall to form a unitary structure.  
   
   
       14 . A turbine engine casing in accordance with  claim 12  wherein said metal plug comprises a first portion adjacent said tapered portion, said metal plug located in said tapered opening with said first portion extending beyond an outer surface of said outer wall.  
   
   
       15 . A turbine engine casing in accordance with  claim 14  wherein said metal plug comprises a second portion adjacent said tapered portion, said metal plug located in said tapered opening with said second portion extending beyond an inner surface of said outer wall.  
   
   
       16 . A turbine engine casing in accordance with  claim 12  wherein said metal plug comprises a contoured shape that mirrors a predetermined shape of a boss.  
   
   
       17 . A gas turbine engine comprising: 
 a compressor;    a high pressure turbine; and    an engine casing extending circumferentially around said compressor and high pressure turbine, said casing comprising:    an outer wall having a tapered opening extending therethrough; and    a metal plug having a tapered portion located at least partially in said tapered opening, said tapered portion of said metal plug mating with a side wall of said tapered opening in said outer wall.    
   
   
       18 . A gas turbine engine in accordance with  claim 17  wherein said metal plug is welded to said outer wall to form a unitary structure.  
   
   
       19 . A gas turbine engine in accordance with  claim 17  wherein said metal plug comprises a first portion adjacent said tapered portion, said metal plug located in said tapered opening with said first portion extending beyond an outer surface of said outer wall.  
   
   
       20 . A gas turbine engine in accordance with  claim 19  wherein said metal plug comprises a second portion adjacent said tapered portion, said metal plug located in said tapered opening with said second portion extending beyond an inner surface of said outer wall.  
   
   
       21 . A turbine engine casing in accordance with  claim 17  wherein said metal plug comprises a contoured shape that mirrors a predetermined shape of a boss.