The factors affecting the slagging on tubes of superheaters and reheaters were analyzed.Reducing the heat absorption deviation between each panel was pointed out as the key points to prevent slagging.Improving the uniformity of temperature and speed of flue gas in boiler width direction was the effective way to eliminate the heat deviation of superheaters and reheaters.The high temperature panel safeguard supervisory system(PSSS)was applied to investigate the temperature field variation and slagging on tube panel of superheater and reheater in boiler of ultra supercritical 1036MW unit in Huaneng Haimen Power Plant phase I.After several measures were taken

such as optimizing the aerodynamic field in furnace

preventing the flame swepting and adhereing the water wall

effectively controlling the formation of reducing gas in furnace

decreasing the flue gas temperature

and conducting soot blowing

the ash deposition and slagging on high temperature reheater was eliminated.