基于有限元法的热采井套损机理研究  

RESEARCH ON CASING FAILURE MECHANISM OF THERMAL PRODUCTION WELL BASED ON FINITE ELEMENT METHOD

作　　者：张宇[1] 况雨春[2] 伍开松[2] 魏春禺[1] 

机构地区：[1]中石化河南油田分公司石油工程技术研究院 [2]西南石油大学

出　　处：《钻采工艺》2008年第4期102-104,1,共3页Drilling & Production Technology

基　　金：四川省青年科技基金项目(项目编号:07ZQ026-014);教育部留学回国人员科研启动基金"山前推覆体钻具防断与打快机理研究"(教外司留[2007]24号)

摘　　要：注汽井套管既受到注汽温度所产生的热应力的影响,又受到套管、水泥环和岩层等结构应力的影响。文章对注汽井套管的失效机理和原因进行分析,归纳总结影响失效的因素;然后利用ANSYS软件建立了套管、水泥环和岩层系统的热—结构耦合的二维平面有限元分析模型。研究了参数变化对热-结构耦合的套管强度的影响。分析结果表明,在小于14mm之前套管壁厚增加会明显降低套管最大峰值应力,此后套管壁厚增加套管最大峰值应力下降速度会减缓。仅从热膨胀角度来看,套管最大峰值应力随蒸汽温度增加而增加。310°C以后套管最大峰值应力随蒸汽温度增加会加剧。The casing damage of steam injection well is not only influenced by the thermal stress, but also by the structural stress of casing, cement, rock and so on. At first this paper analyzed the failure mechanism and causes of the casing in steam injection well and got the factors of casing failure. Secondly the two-dimension plane finite element model which applied in thermal-structure coupling condition for casing, cement hoop and rock was developed by using ANSYS software. At last, the influence of the parameters change on casing strength in thermal-structure coupling condition was studied. The result showed that when casing wall thickness is less than 14mm, the maximum equivalent stress will decrease evidently with the increasing of casing thickness, and when it is more than 14mm, the decrease speed of the maximum equivalent stress will be mitigated. From the viewpoint of thermal expansion, the casings' maximum equivalent stress will increase when the stream temperature increases. When the stream temperature is more than 310°C, the casings' maximum equivalent stress increases sharply.

关 键 词：注汽 套管 温度 有限元 耦合 

分 类 号：TE931.2[石油与天然气工程—石油机械设备]