【摘要】 某高压聚乙烯装置在转产乙烯-醋酸乙烯共聚物(EVA)后,聚合反应器出口处高压调节阀出现严重损伤。通过荧光光谱分析、金相分析、扫描电镜(SEM)分析、能谱分析(EDS)和流场数值模拟等分析手段对材料的组织结构、成分和形貌进行了分析,结合阀门运行工况,认为造成高压阀门损伤的原因主要为空蚀。浸泡法和电化学方法分析表明,醋酸乙烯的腐蚀性较小;针对失效原因,在试验室内对候选材料和工艺进行了抗空蚀性和抗冲蚀性试验评价,通过与母材的性能对比,最终优选出抑制阀门损伤最佳的候选材料和工艺。更多还原

【Abstract】 Serious damage arose in high pressure regulating valve at the outlet of polymerization reactor after converting to produce ethylene vinyl acetate copolymer( EVA). Combined with the operation of valve,main cause of the damage was found to be cavitation,depending on the analysis of microstructure,composition and morphology of materials with the means of fluorescence spectrum analysis,metallographic analysis,scanning electron microscopy,energy spectrum analysis and flow field numerical simulation. The corrosion of vinyl acetate was weak,which was proved by immersion method and electrochemical method. The cavitation resistance and erosion resistance of the candidate materials and processes were evaluated,and the optimal material and process were confirmed ultimately by comparing with the parent material.更多还原