油气井堵漏波纹管加压膨胀过程中位移-应力变化规律

基于油气井钻井中的波纹管堵漏技术,采用ANSYS软件有限元分析方法和现场试验,对堵漏波纹管膨胀过程中位移-应力变化规律进行了研究。采用双重非线性分析方法计算波纹管的膨胀变形,得到了波纹管施工加压膨胀过程中的等效应力分布云图以及波纹管膨胀过程中的位移、应力变化规律。现场波纹管加压试验结果表明,波纹管加压膨胀变形过程的模拟计算结果与试验结果有着同构的一致性。波纹管加压膨胀变形过程中,其应力、应变对应于管体几何形状呈对称分布。管体各处的等效应力和应变不同,其大小主要取决于该处的曲率半径,在波峰和波谷区域产生最大等效应力和最大应变。在此基础上回归出了波纹管管径几何尺寸变化与胀圆所需压力值之间的数学关系式。

ariation rule of displacement and stress of expandable-profile liners during expanding process for leak plugging in oil-gas wells

On the basis of leak plugging in oil and gas drilling engineering, the variation rule of displacement and stress of expandable -profile liners during expanding process was analyzed by using the software ANSYS and field test. The expanding strain of expandable-profile liners was calculated by means of dual non-linear analysis. The nephograms of equivalent stress and the variation rule of displacement and stress of expandable-profile liners during expanding process were obtained. The result of the calculation was verified by field test. The simulation and calculation results for the expanding process of profile liners were isomorphic and consistent with the tested result. The stress and strain of the expandable-profile liners were symmetrically distributed over the geometric shape of the pipeline, but equivalent stress and .equivalent strain on the different region of pipes rested with the curvature radius. The maximal equivalent stress and strain appeared in the wave peak and wave trough. The mathematical formulations about diameters of expandable-profile liners and value of expanding pressure were regressed.