Abstract:For a certain power plant, lowtemperature reheaters of two boilers leak many times and the reheat steam temperature is lower. This paper introduces the problems, comprehensively analyzes their reasons, and proposes solving idea and concrete method, that is, to reduce the number of tubes of lowtemperature reheater and enlarge the flow sectional area of flue gas while keeping the designed flue gas distribution value between sides of lowtemperature reheater and lowtemperature super heater constant in order to decrease flue gas velocity and reduce wearing. In addition, through expanding the heating surface to enlarge the heat exchange area of lowtemperature reheater, it could reduce the wearing and increase the reheat steam temperature of lowtemperature reheater.

Keywords:coalfired boiler, lowtemperature reheater, reheat steam temperature, wear, leakage, flue gas, comprehensive treatment