During the operation of a boiler in a power plant, the water wall tube burst and leaked. In order to find out the reason of tube rupture, a comprehensive experimental study was made on the sample with macro morphology, chemical composition, metallography, SEM and EDS. The results show that due to the high sulfur content in the combustion medium of the boiler, a large amount of sulfate containing sulfur elements will deposit on the outer wall of the water wall tube during the long-term operation. In the high temperature environment of the boiler, the thermal corrosion of sulfate deposit, that is, high temperature sulphur corrosion, is formed on the side of the water wall wall steel tube, which leads to the continuous thinning of the wall thickness. And finally, explosion leakage occurs under the action of the internal high-temperature and high-pressure medium.

No abstract

Temperature regulation by desuperheater spray is an important part to ensure the stable operation of utility boiler. However, due to the bad working conditions, the spray pipe of Desuperheater will produce strong vibration, and the connected equipment will have alternating stress. At the same time, due to design or manufacturing reasons, abrasion or cracking occurs at the welding part or the contact part between the water spray pipe and other parts. Taking measures to ensure stable operation, reasonable design and qualified manufacturing can effectively guarantee the safe operation of power plant equipment.