热采水平井完井筛管参数对管柱稳定性影响研究

摘要

To study the influence of the screen pipe parameters on the stability of screen pipe for thermal recovery horizontal well completion,the unsteady Euler formula of compression bar is introduced.Taking the thermal recovery well of Well H03-Y5 for case study,a three-dimensional finite element model is established using ANSYS software to analyze the influence of the screen pipe parameters,such as hole density,hole diameter and wall thickness,on the stability of the screen pipe during thermal recovery.The results show that,in the process of thermal recovery of Well H03-Y5,the load resulting in third-order instability failure is far greater than that of the first and second-order failure loads when the completion screen is subjected to axial load.The critical load value is positively correlated with the screen hole density and wall thickness,but is negatively correlated with screen aperture.To ensure the stability of the horizontal section of the casing string,increased screen hole density,reduced hole size and increased wall thickness are preferable.According to the characteristics of perforated casing and finite element calculation,the formula of overall stability critical load under changing hole density and hole diameter of perforated casing is deduced.The formula has good applicability.The research results can provide reference and basis for the design and failure prevention of the screen pipe in thermal recovery process.%为研究热采过程完井筛管参数对热采水平井完井筛管柱稳定性的影响,引入压杆失稳欧拉公式.以热采井H03-Y5井为例,通过ANSYS软件建立三维有限元模型,分析热采过程中孔密、孔径和壁厚等筛管参数变化对筛管完井管柱的稳定性影响.研究结果表明:在热采井H03-Y5热采过程中,完井筛管受轴向载荷作用时,发生3阶失稳破坏的载荷要远大于1、2阶破坏载荷;临界失稳载荷值随着筛管孔密和壁厚变化呈正相关,与筛管孔径呈负相关;为保证水平段套管柱的稳定性,需要在完井时增加筛管孔密、减小孔径或选用较大壁厚筛管.根据开孔套管特征及有限元计算结果,推导出开孔套管随孔密和孔径变化时的整体失稳临界载荷计算公式,该公式具有良好的适用性.研究结果可为热采过程中筛管柱的设计和失效预防提供参考和依据.