摘要
采用金相检验、化学分析、力学性能和扫描电镜对某钢厂锅炉顶棚过热器管爆裂原因进行了分析。结果表明,过热器长期过热导致管胀粗、局部减薄,最终形成裂纹。由于裂纹引起泄漏,使回路其余段内冷却工质的流量减小,导致泄漏处的下游发生短时过热爆管,出现大破口。锅炉短期使用的情况下爆管,且显微组织严重球化,证明失效过热器运行时内管壁温度远远超过额定温度318℃,20G钢安全余量不足是导致爆管的主要原因。
The burst of a superheater tube in the roof of a steel mill＇s boiler was analyzed by metallography inspection, chemical composition analysis, mechanical properties test, and SEM observation. The resuhs show that the superheater tube is swelled and its thickness decrease because of long-term over-temperature operation, leading to crack. Microstructure of the tube burst used for a short time is serious spheroidized structure,it is shown that operation temperature of the burst tube exceeds far from the nominal temperature 318 ℃. That is the main reason leading to the tube burst.
出处
《金属热处理》
CAS
CSCD
北大核心
2009年第9期105-107,共3页
Heat Treatment of Metals
