| Tube bursting of superheater or reheater is often happened in large capacity power plants, which severely threatens safety of boiler. There are many reasons resulting in tube bursting, such as veracity of design standard, choice of boiler type and tube materials, arrangement of superheater and steam tempering system, quality of Boiler manufacturing, building and repairing, rationality of operating manner and so on. A large proportion of tube bursting is caused by flow rate deviation induced by incorrect configuration of superheater and reheater system. Aiming at the frequently tube bursting of roof superheater, many aspects as configuration of superheater system, crystal lattice of bursting tube, thickness of ferric oxide, combustion in furnace are discussed. Especially flow rate distribution in heated tubes of roof superheater with bend near inlet header is experimentally studied in detail. It is found that flow rate deviation is not same at different locations in bend tube and flow rate in straight tube near bend tube outlet also affected by the bend. Finally, based on the analysis, technical schemes to eliminate flow rate deviation and avoid tube bursting are given. Further more, the schemes have been carried into execution and settled the problem, which assures economically operating of power plant with safety.
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