摘要
油田开采到中后期,疏松砂岩地层油井套管损坏愈来愈突出,出砂已成为影响油井产能和损害设备的严重问题。为此针对油田的实际情况,分析疏松砂岩地层的出砂机理,建立了套管、水泥环和地层的三维有限元模型。模型中采用了基于Mohr-Coulomb屈服面的弹塑性本构关系,利用有限元法研究在地层参数一定的条件下,当出砂量变化时,出砂部位、出砂周围区域及射孔孔眼处套管应力变化情况。研究结果表明:随井深和出砂量的加大,套管管体和射孔孔眼处的轴向应力和有效应力都明显增大。这为研究疏松砂岩地层套管的损害机制及防治措施提供了理论依据。
Along with the exploration of oil-field in the medium and late terms, the problem of the casing damage which is resulted from the reservoir of loose sandstone is becoming the focus of the study. The sand production has become a serious problem that influences well productivity and damaging production equipment. According to real properties of oil field, the sand production mechanism of the reservoir of the loose sandstone is discussed and 3D finite element model of casing-cement sheath-formation is established. An elasto-plastic constitutive model is utilized on the basis of Mohr-Coulomb yield surface. The model, based on the finite element method, is used to discuss the changing of the sand production position and its surroundings, and the changing of the casing stress where the perforated wellbore is located when the sand production changes under the given parameters. The results indicate that the casing stress condition changes greatly with well depth and the sand production quantity. The study provides the basis for the research of the casing failure mechanism and controlling measure of the loosen sandstone reservoirs.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2005年第11期1905-1910,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
中国石油化工股份有限公司资助课题(P0008研究内容之一)
关键词
石油工程
三维仿真
出砂
有效应力
轴向应力
Finite element method
Oil well production
Oil wells
Sand
Sandstone
Stresses
Three dimensional computer graphics
