超短半径水平井柔性壳力学分析及强度评价

摘要

The strength of slotted flexible shell affects the drilling success in ultra-short radius horizontal well.It is significant to carry out the research of flexible shell strength.Flexible shell is a kind of slender slotted structure.The step calculation method of flexible shell is established.According to the structure,it developed a whole,three-dimensional,finite element model of shell in deflecting section which had three kinds of radius of curvature,and finished single section flexible shell model.And then the dangerous section and deformation state of the shell was got.It is necessary to set up the partial model and impose dangerous loading on it for accurately simulating the details of the partial structures and for analyzing and calculating.Through the calculation,this shell can bear 40 kN axial load.This study provides an effective method to assess the safety performance of flexible shell in ultra-short radius horizontal well.%柔性壳的强度影响超短半径水平井的钻井成功率,由于柔性壳是开槽的细长形结构,不能采用常用方法评价其强度.建立了分步计算法,并建立了3种曲率造斜段柔性壳整体三维接触非线性有限元模型和单节柔性壳局部模型,得到柔性壳受力变形状态及危险截面.将整体模型中得到的危险截面上的载荷施加到局部模型中,对其进行强度评价,得到3种曲率造斜段柔性壳均能够承受40 kN的轴向载荷.为评价柔性壳的安全性能提供了一种有效的计算方法.