计量分离器至加热炉生产汇管腐蚀失效分析

计量分离器至加热炉的生产汇管,由于其输送介质的特殊性,汇管出现腐蚀失效。通过对腐蚀失效油管进行的化学成分分析、金相分析、腐蚀区域微观分析和油腐蚀产物评价,结果表明失效与材质无关,其化学成分均符合技术协议要求并由铁素体+珠光体组成。腐蚀介质中由于含有溶解氧,钢材表面发生了氧还原反应,钢材表面形成酥松的α-FeOOH,并由于氯离子的存在,最终导致生产汇管由内腐蚀发展为腐蚀穿孔。

The Analysis for Corrosion Failure of Manifold from Metering Separator to Heating Furnace

The production manifold from the metering separator to the heating furnace has corrosion failure due to the particularity of conveying medium.The corrosion failure is analyzed through chemical composition analysis,metallographic analysis,micro analysis of corrosion area and evaluation of oil corrosion products.The results show that the failure has nothing to do with the material and the chemical composition of the failure conforms to the technical protocol and consists of ferrite and pearlite.Due to the presence of dissolved oxygen in the corrosive medium,oxygen reduction reaction takes place on the steel surface,resulting in the formation of de-loosened carbon-feooh on the steel surface,and the presence of chlorine ions eventually leads to the development of corrosion perforation of the production manifolds from internal corrosion.