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[1]李铁明,王志彬,石红艳.氢致微裂纹应力腐蚀损伤管道的寿命预测[J].油气储运,,30():637-639.[doi:10.6047/j.issn.1000-8241.2011.08.010]
 Li Tieming,Wang Zhibin,Shi Hongyan.Service life prediction of pipeline under hydrogen-induced microcrack stress corrosion[J].Oil & Gas Storage and Transportation,,30():637-639.[doi:10.6047/j.issn.1000-8241.2011.08.010]

氢致微裂纹应力腐蚀损伤管道的寿命预测    ( 打印/导出/复制)
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[摘要]管道的断裂损坏常常始于微裂纹,研究微裂纹的形成原因、分布情况、扩展规律、扩展速率和影响因素等对于管道的寿命预测有重要的参考价值。基于损伤力学原理分析了管道应力腐蚀损伤演
化模型,根据微裂纹扩张的位能和动能计算式以及能量守恒原理,推导得出氢致微裂纹扩展速率与管道剩余寿命的关系:微裂纹扩展速率与氢压有关,随着氢压的增大而增大。结合实例计算了管输
介质H2S 和CO2 含量对管道剩余寿命的影响规律,结果表明:当管道中同时存在CO2 和H2S 时,管道腐蚀加剧;当输送压力和其他参数不变时,随着H2S 和CO2 含量增加,管道剩余寿命逐渐减小。

[中图分类号]TE988[文献标志码] A [doi]A
Li TiemingWang ZhibinShi HongyanLi Tieming:Oilfield Construction Engineering Company of Southwest Petroleum Bureau,Sinopec,Deyang,Sichuan,618000.
[Abstract]Fracture of pipeline usually begins with microcracks,and it is very important to study its formation,distribution,propagation in
the service life prediction of pipeline. The evolution model of stress corrosion damage of pipe is analyzed based on the damage
mechanics theory. The relationship between the residual life of pipeline and the growth rate of hydrogen microcrack is derived
according to energy conservation law and the calculation formula for the expansion of potential energy and kinetic energy.
Result shows that crack growth rate is increased with the increase of hydrogen pressure. The effect of H2S and CO2 contents(two
main corrosion factors) on the residual life of pipeline is analyzed through a case. The results are as follows:(1)the corrosion of
pipeline is aggravated when both H2S and CO2 exist in the pipeline;(2)the residual life of pipeline will decrease if H2S and CO2
contents are increased and the operation pressure and other parameters are constant.

????? ?在氢压的作用下,不同层面的相邻氢鼓泡裂纹相互连接,形成具有阶梯状特征的内部裂纹,即氢致微裂纹,微裂纹有时可扩展到金属表面[1]引起管道氢致微裂纹的原因是:在H2S 溶液中产生的氢原子通过金属表面,深入基体内部,氢原子在金属内部沿轧制方向在非金属夹杂物和晶体缺陷等处聚集,结合成氢分子,产生巨大的内压力,导致形成微裂纹。可见,形成氢致微裂纹必须具备的条件[2-3]包括:其一,材料内部存在夹杂、夹层或微裂纹缺陷,这是内因;其二,介质中H2O和H2S 同时存在且H2S 含量较高,氢离子是形成氢致微裂纹的外因;其三,材料表面为活性状态。氢致开裂涉及氢的来源、传输、去处及造成的结果等过程。管道的应力腐蚀寿命包括起始寿命期,即从管道与环境接触直至微裂纹产生的时间,用损伤力学的方法可以建立应力微裂纹起始寿命的计算损伤模型;扩展期是微裂纹延伸扩展的时间;快断期为单纯机械性断裂的最后一段很短的时间,可以通过预制微裂纹试件的应力腐蚀试验,结合断裂力学确定。
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