某厂硫焚化炉出口处的手动高温阀在使用一个月后发生断裂。采用宏观观察、化学成分分析、金相检验、扫描电镜及能谱分析、有限元分析等方法分析了该高温阀断裂的原因。结果表明:该高温阀的阀轴中存在严重的非金属夹杂物和较多的碳化物,使材料的耐腐蚀性能下降;在焚化炉实际运行过程中,高温阀的工作应力已经超出材料的屈服强度和强度极限,最终导致高温阀断裂。

The manual high-temperature valve at the outlet of a sulfur incinerator in a certain factory broke after one month of use. The causes of the fracture of the high-temperature valve were analyzed by macroscopic observation, chemical composition analysis, metallographic examination, scanning electron microscopy and energy spectrum analysis and finite element analysis. The results show that there were serious non-metallic inclusions and a large amount of carbides in the valve shaft of the high-temperature valve, which reduced the corrosion resistance of the material. In the actual operation process of the incinerator, the working stress of the high-temperature valve had exceeded the yield strength and strength limit of the material, ultimately led to the fracture of the high-temperature valve.