WELDING METHOD FOR ALLOY COATED BOILER COMPONENT AND SELF-FLUXING ALLOY COATED BOILER COMPONENT

摘要

PPROBLEM TO BE SOLVED: To provide an alloy coated boiler component preventive of thermal shock cracking even when welded and connected by applying a welding coating of an alloy material having improved erosion and/or corrosion resistance over a whole region of a protection required portion. PSOLUTION: A superalloy coating 15 is applied to the end to be welded and connected over a quick temperature rise region C including its vicinity where thermal shock cracking may occurs during welding work. On the other hand, a self-fluxing alloy coating 16 is applied to the other remaining regions than the quick temperature rise region C. The alloy coatings 15, 16 each have Ni-rich Ni-Cr components accounting for the majority, but the superalloy coating 15 contains B of 0.1% or less and Si of 0.5% or less and the self-fluxing alloy coating 16 contains B and Si of 1-5% each. PCOPYRIGHT: (C)2006,JPO&NCIPI