Abstract:

Thermal power plant boilers heatabsorbing tube sometimes may explode due to long overtemperature or shortterm overheating in the daily operation. This paper analyzes the case that after the analysis and solution of the explosion of the heatabsorbing tube, other place which had been affected by the proexplosion had been damaged by a sudden secondleakage. By means of macro analysis, material analysis, metallographic analysis and other methods, the weld organization where the leakage was caused and the nearby tube samples were analyzed. The reason for the second leakage is due to the large burst stress at the fillet weld at the upper header after the first burst, and the secondary leakage from the fillet weld zone occurred after the start of boiler. Therefore, after the treatment of bursting tube, a nondestructive testing should be made on relevant metal parts comprehensively to eliminate hidden dangers.

Key words:

">">thermal power plant；boiler；heat">">absorbing surface tube；explode；secondary leakage