平阴尿素合成塔起爆源处层板应力腐蚀开裂分析

Analysis on stress corrosion cracking of layer plates in initiating explosion location of Pingyin's urea reactor

为了仔细分析平阴尿素合成塔发生爆炸的原因,分析了该塔起爆源——热电偶下方层板上裂纹的开裂形貌,发现存在明显的应力腐蚀裂纹和爆炸生成裂纹。分析了引起应力腐蚀开裂的介质因素,表明检漏蒸汽的泄漏和敏感元素的存在是造成层板应力腐蚀的根本原因。

For analyzing the cause of urea reactor explosion in Pingyin Chemical Fertilizer Plant to prevent the similar accident recurring, the fracture appearance of layer-plates＇ cracks in initiating explosion location under the thermocouple were analyzed. Both stress corrosion cracks （SCC） and explosion induced cracks were found. The sensitive medium which induced the SCC was analyzed. The results show that the release of the leakage detection steam and sensitive substance are the primary reason for the SCC of layer-plates.