马惠线储罐沉积水中常用管线钢的腐蚀性对比

摘要

[Objective]Proper material selection is significant for internal corrosion protection of newly-constructed pipelines.[Methods]Corrosion behavior of 5 types of commonly used pipeline steels X42,X52,X60,X65 and X70 were investigated through corrosion weight loss test carried out in storage tank water of Mahui pipeline.Corrosion products were analyzed through surface analysis technology SEM and XPS.[Results]The results of this test showed that the corrosion rates of these 5 types of pipeline steels first arose then decreased with the increase of test temperature and reached their maximum at 48℃.The corrosion rates of these 5 types of pipeline steels first arose then decreased with the increase of the flow velocity of the test water and reached their maximum at 0.18 m/s.Under static conditions,the corrosion rates of different strength grade pipeline steels showed little difference,and pipeline steels with higher strength grade showed higher pitting sen-sitivity.However,under the conditions of flow-ing water,pipeline steels with higher strength grade showed higher corrosion resistance.[Conclusion]Taking corrosion resistance,erosion resistance and pitting resistance into consideration,X60 and X65 pipeline steels were recom-mended for Mahui crude oil pipeline.%【目的】通过腐蚀评价进行合理选材,预防新建长输原油管道内腐蚀。【方法】通过腐蚀失重实验,研究X42、X52、X60、X65和 X70共5种常用管线钢在马惠线储罐沉积水中的腐蚀行为,并结合 SEM和 XPS表面分析技术分析其腐蚀产物特性。【结果】随着温度的升高,5种管线钢腐蚀速率先升高后降低,在48℃时腐蚀速率最高。随着流速的增加,腐蚀速率先升高后降低,在流速为0.18 m/s 时腐蚀速率最大。在静态下,不同钢级管线钢腐蚀速率差别不大,钢级较高的管材点蚀倾向性较高；而在流动的腐蚀环境中,钢级较高的管材耐蚀性相对较高。【结论】综合考虑管线钢的耐腐蚀、耐冲蚀和耐点蚀性能,在马惠线内腐蚀环境中建议选用X60和 X65钢。