非均匀载荷下稀油井套管的抗外挤强度研究  

Effect of Non-Uniform Loading on Collapsing Strength of Casing in Thin Oil Well

作　　者：孙新[1] 裴晶晶[1] 谢斌[1] 杨尚谕 王航 韩礼红 SUN Xin PEI Jingjing XIE Bin YANG Shangyu WANG Hang HAN Lihong(Xinjiang Oilfield Corporation of China Natural Petroleum Corporation, Karamay, Xinjiang 834000, China CNPC Tubular Goods Research Institute, State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials, Xi＇an, Shaanxi 710077, China)

机构地区：[1]中国石油天然气股份有限公司新疆油田分公司,新疆克拉玛依834000 [2]中国石油集团石油管工程技术研究院石油管材及装备材料服役行为与结构安全国家重点实验室,陕西西安710077

出　　处：《石油管材与仪器》2016年第5期69-72,共4页Petroleum Tubular Goods & Instruments

摘　　要：基于Von-Mises强度准则,建立套管-水泥环-地层受力模型,有限元方法仿真模拟地应力外挤过程,数值计算套管等效应力分布,研究非均匀载荷对稀油井套管抗外挤强度的影响。结果表明:非均匀载荷下套管等效应力分布趋于集中,最大等效应力出现在套管的内壁;随非均匀系数的增加,最大等效应力不断增大,非均匀系数1.6时,最大等效应力超过屈服强度,套管挤毁失效。非均匀载荷下抗挤强度降低的机理归因于套管圆周上应力集中造成的局部失稳破坏。Based on the Von-Mises stress criterion,the effect of non-uniform loading on collapse strength of casing in thin oil well was investigated through casing-cement-formation model,analogue simulation the extrusion process from crustal stress,and then numerical calculation the equivalent stress. The results showed that the distribution of equivalent stress becomes more concentration gradually,and the maximum equivalent stress occurs in casing inside wall under non-uniform loading. Moreover,as non-uniform factor increasing,the maximum equivalent stress enhance continuously. When non-uniform factor reaches to 1. 6,the maximum equivalent stress exceeds yield strength,and then the casing fails due to collapse. The mechanism of reduction in collapsing strength can be attributed to local buckling failure from stress concentration along casing circumference under non-uniform loading.

关 键 词：稀油井 外挤强度 非均匀载荷 套管 

分 类 号：TE931[石油与天然气工程—石油机械设备]