Causes leading to overtemperature deformation and tubeburst leakage of adjusting heating surface

hightemperature superheater

and hightemperature reheater in four boilers made from former Soviet Uninion in Zhangze Power Plant have been analysed

pointing out the main causes resulting in overtemperature tubeburst of hightemperature heating surface

such as faulty organization of combustion in the furnce

shiftup of combustion centre

comparatively large heat deviation along width and height of the furnace

too small outlet furnace arch

serious ash deposition on hightemperature heating surface

and unreasonable connection of tertiaryair pipelines in pulverized coal preparation system etc.. Through combustion optimization adjusting test

strictly control outlet flue gas temperature of the furnace

reducing heat deviation along outlet of the furnace

and properly retrofitting the system

the overtemperature leakage of heating surface has been effectively restrained

greatly enhancing safety of boiler operation.