| 摘要 |
PROBLEM TO BE SOLVED: To facilitate repair welding for cracking by repairing cracking generated on a nozzle by an overlaying layer having multilayers in a welding crosswise direction with a specified pass numbers, in a nozzle for a gas turbine provided with a blade part and a side wall. SOLUTION: In the case where cracking 30, 31 generated on a gas turbine nozzle are repaired, a multilayered overlaying layer having 3 pass or more is formed in a crosswise direction by means of TIG welding after the cracking 30, 31 are completely cut by means of carbide cutter. In the case where cracking generated o the nozzle is repaired by the overlaying layer by a gas turbine nozzle made of Co-base casting alloy including C: 0.20 to 0.30% by weight, Si: 1.0% or less, Mn: 1.0% or less, Cr: 20 to 32%, Ni: 9 to 12%, W: 5 to 10%, Fe: 5% or less, and B: 0.0005 to 0.015%, the overlaying layer is formed of Co- base alloy including C: 0.03 to 0.10% by weight, Si: 1.0% or less, Mn: 1.0% or less, Cr: 20 to 30%, Ni: 15% to 23%, W: 3 to 10%, Ta: 5 to 15%, and Zr: 0.05 to 0.7%. |
