燃煤锅炉内含尘烟气的冲蚀作用是换热器失效的主要原因之一。本文设计加速试验，研究燃煤锅炉常见换热材质20g在不同飞灰冲击速度(40~120 m/s)、飞灰粒径(65、180和320 μm)以及不同温度(300、350和400 ℃)下的冲蚀磨损情况并分析其冲蚀机理。结果表明：磨损量随冲刷速度的增加呈指数增长，温度升高，速度对冲蚀的影响在逐渐减弱；磨损量随着温度的升高先降低后增高，在300 ℃冲蚀量最小。粒度对磨损量的影响随冲刷速度的增大变得越加明显，冲蚀量随飞灰粒径的增加逐渐减小，在粒径大于180 μm后，冲蚀磨损量不再受粒径影响。

The erosion of dusty flue gas in coalfired boilers is one of the main reasons for the failure of heat exchangers.In this paper,an accelerated test was designed to study the erosion wear of 20g of common heat transfer materials of coalfired boilers under different fly ash impact velocity(40~120 m/s),fly ash particle size(65、180 and 320 μm) and different temperature(300、350 and 400 ℃),and then the erosion mechanism was analyzed.The results show that the wear rate increases exponentially with the increase of the scouring speed,and when the temperature increases,the effect of velocity on erosion is gradually weakened.The wear rate decreases first and then increases with the increase of temperature,and the erosion rate is the smallest at 300 ℃.The effect of particle size on the wear rate becomes more and more evident with the increase of the scouring speed.The erosion rate decreases with the increase of the fly ash particle size.When the particle size is larger than 180 μm,the erosion wear is no longer affected by the particle size.

TK224.9

国家重点研发计划（2016YFB0600701）