含硫气井套管变形与修整对其性能的影响  

Effects of deformation and trimming on the performances of casings in sulfur gas wells

作　　者：邵理云[1] 李国平[1] 赵军[1] 曾德智[2] 张智[2] 施太和[2] 

机构地区：[1]中国石化中原油田普光分公司,四川达州636156 [2]西南石油大学油气藏地质及开发工程国家重点实验室,成都610500

出　　处：《中国科技论文》2012年第8期603-606,共4页China Sciencepaper

基　　金：国家自然科学基金资助项目(51004084);高等学校博士学科点专项科研基金资助项目(20105121120002)

摘　　要："5·12"汶川大地震诱导下三叠统嘉陵江组膏盐层蠕变,导致四川地区一些气井不同程度地产生了套管变形。为保证气井正常生产,对套管进行了适度整形,套变井段经历反复修磨和胀管。若含硫天然气窜入油套环空,经冷作硬化后的C110套管是否会发生环境开裂值得高度关注。笔者通过模拟套管变形和整形,研究了冷作硬化前后管材拉伸力学性能、硬度的变化情况,采用示波冲击测试方法研究了冷作硬化和NACEA溶液浸泡对材料性能的影响,采用NACE0177DCB法得出了环空保护液中冷作硬化对材料环境开裂的影响。研究结果表明,C110经多次挤压和胀管修磨冷变形后,屈服强度增加,硬度略增加;在经NACEA溶液浸泡后,冲击功降低,示波冲击特性显示其抗环境开裂性能变差;在环空保护液中,H2S分压为1 MPa,模拟井下温度和压力条件下,C110套管冷作硬化前后DCB测试结果无变化,且未见环境开裂裂纹。当环空保护液防护效果良好时,冷作硬化的C110套管可安全服役。The creep of the Triassic Jialing group salt layers induced by the ＂5.12＂ Wenchuan earthquake results in different degrees of clefbrmation in some casings in Sichuan oilfield. Moderate trimming and repeated grinding and expanding of these deformation casings were performed to ensure normal production of gas wells, ff sour gas channels into the annulus between the tubing and the casing, whether environmental cracking occurs in C110 casing after cold hardening is worthy of attention. By simulating the deformation and trimming of the casing, the tensile mechanical properties and hardness were studied before and after the cold hardening process. We studied the effects of cold hardening and NACE A solution soaking on the material properties using the instrumented impact testing method as well as the influence of the cold hardening process on the environmental cracking in the annulus protection fluid using the NACE 0177 DCB method. The results show that the yield slrength of Cll0 casing increases significantly, and the hardness increases slightly after repeated extrusion, expanding and grinding. The impact energy decreases after soaking in NACE A solution, and the ~ented impact properties show its poor resistance to environmental cracking. In the protection fluid, the HzS partial pressure is 1 MPa, the DCB test remalts of ClIO casing do not change before and alter the cold hardening process and no environmental cracking occurs under the simulated downhole temperature and pressure conditions. When the annulus protection fluid has better effects, the cold hardening C 110 casing can serve reliably.

关 键 词：油井套管 变形 冷作硬化 硫化氢 整形 力学性能 环境开裂 

分 类 号：TE931.2[石油与天然气工程—石油机械设备]