Fuel Nozzle of Gas Turbine Combustor and Manufacturing Method Thereof, and Gas Turbine Combustor

Abstract

To provide a fuel nozzle for a gas turbine combustor, offering favorable durability and strength reliability. In a fuel nozzle for a gas turbine combustor, jetting fuel into a combustion chamber of the gas turbine combustor, the fuel nozzle is metallurgically and integrally bonded with a base plate that supports the fuel nozzle, and an interface between the fuel nozzle and the base plate includes a surface in which bonding is performed by a fusion joint or a brazing joint and an inside part in which bonding is performed by pressure bonding.

1 . A fuel nozzle for a gas turbine combustor, the fuel nozzle jetting fuel into a combustion chamber of the gas turbine combustor,
 the fuel nozzle being metallurgically and integrally bonded with a base plate that supports the fuel nozzle,   an interface between the fuel nozzle and the base plate including a surface in which bonding is performed by a fusion joint or a brazing joint and an inside part in which bonding is performed by pressure bonding.   
     
     
         2 . The fuel nozzle for a gas turbine combustor according to  claim 1 , wherein
 a fusion joint is formed by electron beam welding in the interface between the fuel nozzle and the base plate on a surface of the base plate,   a fusion zone is formed in an annular shape along a circumference of a root portion of the fuel nozzle fixed to the base plate, and   the fusion zone has a width and a depth of 1 mm or less each.   
     
     
         3 . The fuel nozzle for a gas turbine combustor according to  claim 1 ,
 wherein the pressure bonding is performed by a hot isostatic pressing process.   
     
     
         4 . The fuel nozzle for a gas turbine combustor according to  claim 2 ,
 wherein the fusion zone is machined to a flat or smooth curved surface with respect to the surface of the fuel nozzle and the base plate.   
     
     
         5 . The fuel nozzle for a gas turbine combustor according to  claim 1 ,
 wherein the inside part of the bonding interface between the fuel nozzle and the base plate is linear and free of undeposited portions.   
     
     
         6 . A gas turbine combustor including the fuel nozzle for a gas turbine combustor according to  claim 1 , the gas turbine combustor being a multi-hole coaxial jet type, wherein:
 a plurality of fuel nozzles are provided in the base plate;   the base plate has a fuel distribution function for distributing fuel to the fuel nozzles; and   an air hole plate is installed, the air hole plate being disposed downstream of the fuel nozzles and having a plurality of air holes through which combustion air is introduced into the combustion chamber,   the fuel nozzles and the air holes being coaxially disposed at fuel jet positions.   
     
     
         7 . A gas turbine combustor including the fuel nozzle for a gas turbine combustor according to  claim 1 , wherein:
 a plurality of fuel nozzles are disposed in the base plate; and   the fuel nozzles are for use with a premixed combustion burner being arranged so as to surround a diffusion combustion burner provided at a central portion of the base plate.   
     
     
         8 . A method for manufacturing a fuel nozzle for a gas turbine combustor, the method comprising:
 (a) fitting a fuel nozzle having an internal through hole into a through hole or a recess provided in a base plate;   (b) bonding, by a fusion joint or a brazing joint, the fuel nozzle to the base plate in an interface therebetween on a surface of the base plate; and   (c) following the step of (b), subjecting the fuel nozzle and the base plate to a pressure bonding process to thereby pressure bond the fuel nozzle and the base plate in the interface therebetween.   
     
     
         9 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 8 , the method further comprising:
 between the step of (a) and the step of (b), (d) covering with a bottom plate a surface of the base plate, the surface being opposite to the surface in which the fuel nozzle is fitted, wherein   in the step of (b), the base plate and the bottom plate are bonded by a fusion joint or a brazing joint in an interface therebetween.   
     
     
         10 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 9 , the method further comprising:
 following the step of (c), (f) drilling a hole in the bottom plate to thereby causing the through hole in the fuel nozzle to pass through the bottom plate.   
     
     
         11 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 9 , the method further comprising:
 prior to the step of (a), (e) closing a bottom surface portion of the through hole in the fuel nozzle, wherein   following the step of (b), each of interfaces of the fuel nozzle, the base plate, and the bottom plate is vacuum evacuated using a vacuum evacuation hole formed in the bottom plate.   
     
     
         12 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 11 ,
 wherein the interface in each of the fuel nozzle, the base plate, and the bottom plate is subjected to a vacuum leak test using the vacuum evacuation hole.   
     
     
         13 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 8 , wherein
 the fusion joint in the step of (b) is formed by electron beam welding,   a fusion zone is formed in an annular shape along a circumference of a root portion of the fuel nozzle fixed to the base plate, and   the fusion zone has a width and a depth of 1 mm or less each.   
     
     
         14 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 8 , wherein the pressure bonding process of the step of (c) is a hot isostatic pressing process. 
     
     
         15 . The method for manufacturing a fuel nozzle for a gas turbine combustor according to  claim 8 , further comprising:
 following the step of (c), (g) applying a flattening process, or a machined curvature process on the surface of the base plate in the interface between the fuel nozzle and the base plate.