采用化学成分分析、金相检验和断口分析等方法,对304L钢D210塔筒体泄漏原因进行了分析。结果表明:D210塔筒体泄漏原因是由于氯离子的存在而产生应力腐蚀开裂所致。由于敏感材料、应力腐蚀环境及应力三个条件共同存在,在一定温度下使其产生应力腐蚀裂纹,裂纹起始于筒体外壁角焊缝处,而后向内壁扩展,最终穿透筒壁,致使该塔筒体在角焊缝处产生破裂泄漏。

The leakage reason in cylinder of the tower D210 was analyzed by chemical composition analysis,metallographic examination and fracture analysis. The analysis result showed that the leakage was caused by stress corrosion cracking which resulted from existing chloride ion. Under the certain temperature,stress corrosion crack produced at the combined effect conditions of sensitive materials,stress corrosion circumstance and tensile stress. The crack,which initiating in fillet weld on outer cylinder,extended to the wall and eventually penetrated the tube wall. Then towers cylinder leaked on the fillet weld.