腐蚀-冲蚀耦合作用下套管柱可靠性研究

项目名称： 腐蚀-冲蚀耦合作用下套管柱可靠性研究

项目编号： No.51274047

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 矿业工程

项目作者： 楼一珊

作者单位： 长江大学

项目金额： 70万元

中文摘要： 目前套管柱设计方法主要有额定载荷组合的强度设计方法和三轴应力强度设计方法，这类方法采用不同安全系数来处理复杂状况，没有考虑生产过程中动态变化因素的影响，也就无法从根本上避免套管柱系统失效事故的发生。通过对套管柱失效类型和失效部位特点的调研分析，根据套管大多是在生产过程中逐渐破坏这一显著特点，提出建立套管柱系统可靠性方法。以具有时间依赖性危险因素（腐蚀、出砂）为主要研究对象，通过理论分析、数值模拟，确定各个危险因素与时间相关性可靠性理论模型。结合物理模拟实验，确定腐蚀-出砂冲蚀参数概率分布和速率模型，采用流体动力学、流固耦合和可靠性方法建立腐蚀-出砂冲蚀可靠性模型；以可靠性模型为依据，将套管柱系统划分为多个系统单元，建立套管柱系统可靠性体系，对危险单元进行定量评估，确保油气井套管柱在整个生命周期的安全性与可靠性。

中文关键词： 腐蚀；套管；冲蚀；安全评估；钻井工程

英文摘要： The methods for casing string strength design are mainly rated load method and triaxial stress method at present. These methods usually use safety factor to cope with complex conditions, without taking dynamics changing factors during production, so it is impossible to avoid the casing string failure. A method for establishing string reliability is proposed according to the fact that the deformation of oil casing is gradually formed with production operation based on casing failure type and locatiion. The time-dependent risk factors of erosion and sand production are studied and a theory model for determining the reliability of every time-dependent risk factor by theoretical analysis and numerical calculation is established. The distrubution of corrosion-erosion parameters and speed formular are determined by physical simulation experiment. The corrosion-erosion model is developed by fluid dynamics, fluid-solid couping and reliability theory. The casing string is divided into several system units by the model and dangerous units are selected and evaluated by the reliability method to ensure the safety and reliabiltiy within the casing's life cycle.

英文关键词： Corrosion；Casing；Erosion；Safety evaluation；Drilling engineering