Method of closing working hole in gas turbine blade top

Abstract

A tip plug is capped on a boss section so as to fit to a hole which is used for detaching a core which is formed in a blade tip section of the gas turbine blade. A butt-section T is melted so as to form a butt-welding section by using a YAG laser beamthere; thus, the hole is plugged by the tip plug. Also, parameters such as an interval between the butt-section T, a member for forming the tip plug, condition for a laser welding operation, and a defocus position of the laser beam are optimized. By doing this, it is possible to control the entering heat amount and prevent the solidification cracking and the liquation cracking reliably. Furthermore, it is possible to melt and weld the butt-welding section more strongly by using a laser having a narrow bead width; thus, it is possible to improve the manufacturing process efficiently and produce a product in uniform quality repeatedly.

Dependencies are inferred from the claim text.