Plug Assembly for Borescope Port Cooling

Abstract

A removable plug assembly modified for port cooling plugs a borescope port but allows controlled leakage to cool surfaces adjacent the port below oxidation limits. The plug assembly has a plunger and plug wherein the plug includes a plurality of flow recesses allowing bypass air to cool the surface having the port, as well as the borescope plug.

What is claimed is: 
     
         1 . A removable plug assembly modified for port cooling, comprising:
 a plunger having a first end, a second end and shaft defined therebetween;   a sealing plug at said second end of said plunger having a first diameter;   said plug having a tapered surface tapering to a second diameter which is less than said first diameter;   a plurality of flow recesses along an outer surface of said plug between at least one surface of said first diameter and at least one surface of said second diameter;   said flow recesses allowing by-pass air to reach a lower surface wherein a port is disposed.   
     
     
         2 . The removable plug assembly of  claim 1 , said plug disposed in a port for a borescope. 
     
     
         3 . The removable plug assembly of  claim 1 , said assembly passing through a first wall. 
     
     
         4 . The removable plug assembly of  claim 3 , said first wall being a combustor casing. 
     
     
         5 . The removable plug assembly of  claim 3 , said assembly passing through a second wall. 
     
     
         6 . The removable plug assembly of  claim 5 , said second wall being a turbine casing. 
     
     
         7 . The removable plug assembly of  claim 1 , said first end of said plunger passing through a bearing. 
     
     
         8 . The removable plug assembly of  claim 1 , said second diameter having a thickness in an axial direction. 
     
     
         9 . The removable plug assembly of  claim 1 , said flow recesses extending through at least one surface. 
     
     
         10 . The removable plug assembly of  claim 1 , said flow recesses extending through two surfaces. 
     
     
         11 . The removable plug assembly of  claim 1 , said flow recesses extending through three surfaces. 
     
     
         12 . The removable plug assembly of  claim 1 , said flow recesses having a first leg and a second leg. 
     
     
         13 . The removable plug assembly of  claim 12 , said first leg being at an angle to an axis of said plunger. 
     
     
         14 . The removable plug assembly of  claim 12 , said second leg extending in an axial direction. 
     
     
         15 . A removable plug assembly, comprising:
 a plunger having an upper end, a lower end and a shaft therebetween;   a sealing plug at a lower end of said shaft said plug having a sealing surface therealong and plurality of flow recesses along said sealing surface;   said plurality of flow recesses allowing by-pass air to move from a first end of said sealing surface to a second end of said sealing surface.   
     
     
         16 . The removable plug assembly of  claim 15  wherein said flow recesses are formed by at least one linear segment. 
     
     
         17 . The removable plug assembly of  claim 15  wherein said flow recesses are curved about said sealing surface. 
     
     
         18 . The removable plug assembly of  claim 15  wherein said flow recesses are formed of linear segments. 
     
     
         19 . The removable plug assembly of  claim 15  wherein said sealing surface is tapered from a first diameter to a second diameter. 
     
     
         20 . A removable plug assembly allowing for port cooling, comprising:
 a plunger for positioning within a borescope port of a gas turbine engine;   said plunger having a first end, a second end and a shaft therebetween;   a plug disposed at said second end of said shaft, said plug having a first diameter disposed on a first side of said port, a second diameter passing into said port and a tapered surface therebetween;   said plug further comprising a sealing surface to engage said port;   at least one flow recess extending from said first side of said portion to said second diameter on a second side of said port allowing cooling air to pass along said tapered surface.