Owing to the corrosive, flammable, and explosive properties of pipeline materials in alkylation units, corrosion failure may result in leakage, fire, and explosion accidents. A bursting accident occurred in the 90° elbow of an alkylation unit pipeline. Failure analysis was performed by macroscopic analysis, metallographic analysis, chemical composition, corrosion form analysis, and corrosion product analysis. Finite element software was used to analyse the flow velocity, turbulence intensity, pressure, and wall stress distribution. The fault tree was combined with the analytic hierarchy process to realise the transformation of the structural importance-judgement factor-judgement matrix and to weight the events that may cause device corrosion failure. The results showed that uniform corrosion and stress corrosion of hydrofluoric acid occur in the pipeline and uniform corrosion is the dominant effect. Hydrofluoric acid corrosion leads to severe thinning of the pipe wall, making its strength drop below the bearing strength and rupture occurs. Quality of internal anticorrosion coating, water content of the medium and working temperature are the key factors to prevent pipeline leakage in alkylation unit.

由于烷基化装置管道材料具有腐蚀性、易燃性和爆炸性，腐蚀失效可能导致泄漏、火灾和爆炸事故。某烷基化装置管道90°弯头发生爆裂事故。失效分析通过宏观分析、金相分析、化学成分分析、腐蚀形态分析和腐蚀产物分析进行。有限元软件用于分析流速、湍流强度、压力和壁面应力分布。将故障树与层次分析法相结合，实现结构重要性-判断因素-判断矩阵的变换，并对可能导致装置腐蚀失效的事件进行加权。结果表明，氢氟酸在管道中发生均匀腐蚀和应力腐蚀，均匀腐蚀是主导作用。氢氟酸腐蚀导致管壁严重减薄，使其强度低于承载强度而发生破裂。内防腐涂层的质量、介质的含水量和工作温度是防止烷基化装置管道泄漏的关键因素。