疏松砂岩层套管受力的有限元分析  

FINITE ELEMENT ANALYSIS OF CASING MECHANICAL PROPERTY IN UNCONSOLIDATED SAND FORMATION

作　　者：肖洲[1] 练章华[1] 陈勇[1] 杨斌[1] 刘昕[1] 

机构地区：[1]油气藏地质及开发工程国家重点实验室·西南石油大学

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

基　　金：国家教育部科学技术研究重点项目(205135)

摘　　要：疏松砂岩层段油气井开采过程中,生产层段由于出砂将在套管外部附近形成空洞,破坏了套管的受力环境,套管外部失去支撑。由于上覆地层压力的作用和地层扰动力的作用,使套管在轴向压力作用下产生屈曲变形,甚至错断。文章用弹塑性有限元法建立了出砂层段套管屈曲变形的空间有限元力学模型。根据此模型,分析了套管内的Von-Mises应力随出砂范围变化的变化过程,定量分析了套管内的应力变化以及套管的侧向位移变化,这些结果为预防套管损坏和屈曲变形提供了理论依据。In the process of oil & gas well exploitation in unconsolidated sand,hollow space will be formed near the casing exterior because of sanding in pay interval,so the force condition of casing will be disturbed.The casing exterior loses support.In the case of overlying formation pressure and disturbing force of formation,the casing will be buckled,even sheared.The finite element model of casing buckling was simulated in sanding formation by elastoplasticity finite element method.Based on the model,the process of variation of Von-Mises stress with the variation of sanding degree was analyzed,meanwhile,the stress variation of casing exterior and the lateral displacement variation were quantitatively analyzed.These research results provided theoretical basis for preventing casing failure and buckling.

关 键 词：油井出砂 套管 变形 有限元 

分 类 号：TE931[石油与天然气工程—石油机械设备]