可膨胀筛管外壳的结构设计及膨胀性能分析

Structural design and expansive behavior analysis of the shell of expandable screen

可膨胀筛管保护外壳通常采用割缝管形式,膨胀后的壁厚变薄、强度降低.为提高保护外壳的膨胀性能,提出了圆形波纹管形式外壳的设想,并采用非线性有限元方法分析其膨胀性能.计算结果表明,外壳的波纹半径与其膨胀性能紧密相关,且难以直接找到最优参数,必须采用多目标优化方法优化外壳的波纹半径.为提高寻优速度,利用BP神经网络技术建立了筛管外壳膨胀性能预测模型,结合MATLAB优化工具箱优化了外壳参数.室内试验表明,优化后的筛管外壳膨胀力小、膨胀均匀、应力储备系数高,为提高可膨胀筛管的现场应用成功率和改善可膨胀筛管防砂效果提供了保障.

The shell of expandable screen generally uses slotted screen tube,its wall becomes thin and its strength decreases when the expandable screen expanses.In order to overcome the shortcomings of the slotted expandable screen,an idea is put forward that the shell of the expandable screen uses circular corrugated tube.The expansive behavior of the corrugated expandable screen is analyzed by using nonlinear finite element method.The analysis result shows that,the expansive behavior of the corrugated expandable screen is closely related to the corrugated radius of its shell,and it is difficult to find the optimal value of the radius unless multi-objective optimization method is used.For enhancing the optimizing speed,a forecast model of the expansive behavior of the corrugated expandable screen is established through BP neural network,the corrugated radius is optimized using MATLAB.Laboratory experiment shows that,the optimized corrugated screen shell has less and homogeneous expansive force and higher stress storage coefficient,which provides safeguards for the successful application of the circular corrugated screen tube and the improvement of sand control result of expandable screen.