近中性土壤溶液中X65管线钢应力腐蚀开裂研究  

Study on the Stress Corrosion Cracking of X65 Pipeline Steel in Near-neutral p H Soil Solution

作　　者：涂圣文[1] 帅健[1] 刘德绪[2] 

机构地区：[1]中国石油大学机械与储运工程学院,北京102249 [2]中原石油勘探局勘察设计研究院,河南濮阳457001

出　　处：《焊管》2015年第1期5-10,共6页Welded Pipe and Tube

基　　金：国家重大科技专项(2011ZX05017-004-HZ04)

摘　　要：将中国西部某管线现场取得的土壤样品配制成土壤溶液,对X65管线钢在该土壤溶液中进行氢渗透、慢拉伸和应力波动试验。通过观察试验数据和试件主断面及表面扫描电镜图,评价X65管线钢在该土壤溶液中发生SCC的敏感性及其他力学因素对SCC的影响。结果表明:X65管线钢在试验土壤溶液中对SCC是敏感的,氢原子的渗入使得敏感性提高,且提升的幅度较大,CO2气体能够促进氢在管线钢中的渗透;应力波动对应力腐蚀开裂初始阶段裂纹的萌生有重要的影响,二次应力波动试验表明,交变载荷的作用能够导致裂纹的进一步扩展。Soil solution was taken from soil samples which were obtained from some western pipeline field in China.Hydrogen immersion test, slow tensile test and stress fluctuation test were conducted in soil solution for X65 pipeline steel.Test data were calculated and SEM of fracture surface and lateral surface of specimens were observed. The susceptibility of SCC of X65 pipeline steel in soil solution was assessed and effects of other mechanical factors on SCC were also studied. Test results showed that X65 pipeline steel is susceptible to SCC in soil solution and hydrogen immersion promotes the susceptibility greatly, and CO2 gas promotes the hydrogen immersion in pipeline steel. Stress fluctuation is with great influence on crack initiation during the preliminary stage of SCC. The secondary stress fluctuation indicated that the effect of alternating load can lead to further extension of crack.

关 键 词：X65管线钢 近中性土壤溶液 应力腐蚀开裂 氢渗透 慢拉伸 应力波动 

分 类 号：TE988.2[石油与天然气工程—石油机械设备]