整体式弹性扶正器结构参数分析

Analysis of Structural Parameters of Integral Elastic Centralizer

随着钻井作业需求及技术的发展,作业深度越来越深,井下作业环境变的复杂多变,对弹性扶正器的性能提出了更高的要求。整体式弹性扶正器的核心部件——扶正器弓片的弹性性能是衡量整个扶正器性能的关键指标。弓片的复位力和其应变能密度是评估弓片弹性特性的重要参数,直接影响着扶正器的工作效率和可靠性。对建立的井眼-扶正器-套管有限元三维模型进行了分析;基于响应曲面法,研究并分析了扶正器的弓片弦长、壁厚、弓片宽度三个结构参数对扶正器复位力与应变能密度影响规律;通过试验验证了有限元分析的可靠性。研究结果表明:影响复位力的主次因素依次为壁厚、弓片宽度、弓片弦长;影响应变能密度的主次因素依次为弓片宽度、壁厚、弓片弦长。研究结果可为整体式弹性扶正器几何结构对复位力与应变能密度分析提供理论参考。

As drilling progresses into deeper formations,the downhole environment gradually becomes more complex and variable,placing higher demands on the performance of the elastic centralizer.The elastic performance of the core component of the integral elastic centralizer,the centralizer arcualia,is the key index to measure the performance of the whole centralizer.Among them,the resetting force of the arcualia and its strain energy density are important parameters to evaluate the elastic properties of the arcualia,and they directly affect the efficiency and reliability of the centralizer.A three-dimensional finite element model of the borehole centralizer casing was established;based on the response surface method,the effects of three structural parameters,namely,arcualia chord length,wall thickness,and arcualia width,on the reset force and strain energy density of the armature were investigated and analyzed,and the reliability of the finite element analysis was verified by experiment.The results of the study show that the primary and secondary factors affecting the reset force are:wall thickness,arcualia width and arcualia chord length;and the primary and secondary factors affecting the strain energy density are:arcualia width,wall thickness and arcualia chord length.The results provide a theoretical reference for the analysis of reset force and strain energy density by the geometry of integral elastic centralizers.