Analytical method for evaluating stress field in casing-cement-formation system of oil/gas wells
摘要:In this paper, we present an analytical method for evaluating the stress field within a casing-cement-formation system of oil/gas wells under anisotropic in-situ stresses in the rock formation and uniform pressure within the casing. The present method treats the in-situ stresses in the formation as initial stresses since the in-situ stresses have already developed in the formation before placement of cement and casing into the well. It is demonstrated that, via this treatment, the present method excludes additional displacements within the formation predicted by the existing method, and gives more reasonable stress results. An actual tight-oil well is analyzed using the present and existing analytical methods, as well as the finite element method. Good agreement between the analytical results and the finite element analysis (FEA) results is obtained, validating the present method. It is also evident that, compared with the present method, the existing method overestimates the compressive stress level within the casing and the cement. Finally, the effects of elastic properties of the formation, cement, and inner pressure of casing on stresses within the casing and cement are illustrated with a series of sensitivity analyses.
关键字:near wellbore region stress evaluation anisotropicin-situ stress initial stress
ISSN号:0253-4827
卷、期、页:卷: 38 期: 9 页: 1273-1294
发表日期:2017-09-01
影响因子:1.205000
期刊分区(SCI为中科院分区):三区
收录情况:SCIE(科学引文索引网络版)
发表期刊名称:APPLIED MATHEMATICS AND MECHANICS-ENGLISH EDITION
第一作者:刘伟,蔚宝华,邓金根
论文类型:期刊论文
论文概要:刘伟,蔚宝华,邓金根,Analytical method for evaluating stress field in casing-cement-formation system of oil/gas wells,APPLIED MATHEMATICS AND MECHANICS-ENGLISH EDITION,2017,卷: 38 期: 9 页: 1273-1294
论文题目:Analytical method for evaluating stress field in casing-cement-formation system of oil/gas wells