封隔器胶筒轴向压缩大变形与双重接触力学分析  

Mechanics Analysis of Large Deformation and Double Contact of Packer Rubber Sleeve During Axial Compressing

作　　者：刘巨保[1] 党黎明[1] 付茂青 王泉[1] 

机构地区：[1]东北石油大学机械科学与工程学院

出　　处：《石油机械》2014年第7期49-54,共6页China Petroleum Machinery

基　　金：国家自然科学基金项目"流致管束振动与碰撞机理的耦合动力学特性研究"(11272085);国家科技支撑计划项目"潜油电泵机组部件组配设计及通过能力仿真技术"(2012BAH28F00)

摘　　要：压缩式封隔器胶筒属大变形材料,在坐封过程中与中心管、套管产生双向接触摩擦,给理论分析带来难度。鉴于此,考虑胶筒材料非线性、几何非线性及双重接触非线性,采用弹性力学理论和橡胶大变形本构关系,推导了胶筒坐封过程中的变形和接触压力计算公式,根据力学基本理论建立胶筒变形方程。将胶筒变形分为自由变形、单向约束变形和双向约束变形3个阶段,利用载荷迭代法求解各阶段的接触压力和压缩量。提出以密封系数作为封隔器坐封的判别条件,密封系数越大,表明密封性能越好;通过密封系数不小于1来判断封隔器是否完全坐封,由封隔器承受的最大压力来判断适用于何种深度的压裂井。该项研究结果可为封隔器设计提供理论依据。Compression packer rubber sleeve is the sealing element with a large deformation for separate layer fracturing. During the packer setting, the rubber sleeve has a bidirectional contact with the center tube and casing produce, making it a challenge for theoretical analysis. Considering the material nonlinearity, geometric nonlinearity and double contact nonlinearity, the formula for calculating deformation and contact pressure of packer setting are developed based on elastic mechanic theory and constitutive relationship of large deformation of rubber. By di- viding the packer into micro pieces along the axle through discrete element method, the deformation equation of the rubber sleeve is established based on the basic theory of mechanics. The rubber sleeve deformations are divided into three stages including free deformation, unidirectional restrained deformation and bidirectional restrained deforma- tion. The contact pressure and amount of compression of each stage are calculated by load iterative method. The sealing factor is proposed as the judgment of packer setting. The larger the sealing factor is, the better the sealing performance is. Fully set packer could be determined if the sealing factor is larger than 1. The depth that the packer can be applied could be determined based on the maximum pressure held by the packer. The study results could provide theoretical basis for the analysis and design of packer setting.

关 键 词：封隔器 胶筒 变形 压缩量 密封系数 力学分析 

分 类 号：TE934[石油与天然气工程—石油机械设备]