锅炉水冷壁腐蚀失效的原因

Corrosion Failure Reason of Boiler Water-cooling Wall

某石化厂三台高压锅炉因水冷壁腐蚀爆管引起锅炉机组停机,严重影响机组安全稳定运行。经检测分析,三台锅炉水冷壁腐蚀主要原因是碱性腐蚀,高含量的碱性介质腐蚀水冷壁迎火面内表面上的钝化氧化保护膜,形成腐蚀溃疡,管壁不断减薄,因不能承受高温高压水蒸气的压力而发生爆管。

Three high peressuer boilers in a petrochemical factory were shut down because of corrosion bursting of water wall,which affected the safety of operation of the unite.A analysis results showed that,the boiler corrosion was mainly caused by alkali corrosion,the inner surface passivation protective films of boiler water-wall tubes corroded by high concentration alkaline medium,and corrosive ulcer formed in the tube wall,which led to coutineous thinning of the tube wall.Finaly the tube bursted when the pressure and the temperature of steam were overloaded.