套损问题影响因素分析

Causes for damage to casing

油田套损问题非常复杂,影响因素众多,给油田生产带来了巨大损失.因此,选择平面有限元对引起套损原因进行分析.引入摩擦元,模拟地层注水后产生的地层错动面,考虑了岩石单元的非线性,编制有限元程序进行了分析运算,给出了套损管损坏的定量分析结果.以地层的相对错动表示套损变形情况,研究了地层倾角、地层压力、浸水域大小和泥岩水化情况改变对套损的影响.分析结果表明:当形成一定范围浸水域后,随着地层倾角增大,地层压力增大,浸水域范围增大和泥岩水化程序增大,套管变形增大.

Casing damage can result in substantial damage to oil wells.The causes for casing damage are complicated and the factors are from many sources.In this paper,using plane finite element method we analyze the causes for casing damage,define the friction element,analogize the deformed stratum after filling water and consider the non-linear rock element.A program of finite element is then used to process some analyses and computations.We quantitatively analyze the casing damage,present the deformation of casing with the change of relative position of stratum and study the angle of inclination of stratum,the pressure of stratum,the size of soaked area and the hydration of marl.The final result shows that when a certain soaked area comes up,the deformation of casing will increase with the increase of the angle of inclination of stratum and the pressure of stratum and the size of soaked area and the hydration of marl.