Abstract: Several bended tubes of #1 boiler second stage superheater of the Xiamen Houkeng Refusefired Power Plant were failed due to cracking during operation. The reason of tube cracking was analyzed, and the feasible solving scheme was proposed and accomplished; then similar fault was avoided effectively. So the safety operation of boiler had been ensured.

Key words: bended tube crack, alternating thermal stress, sealing plate, spray type desuperheater