不同约束方式下膨胀套管的旋转膨胀有限元分析

基于LS-DYNA动态有限元分析,建立了旋转拟合方式的膨胀套管模型,并模拟了整个膨胀过程。通过对套管不同约束方式的模拟结果分析发现,旋转拟合膨胀所需膨胀力为实心锥反拉膨胀的1/5左右,在不同约束方式下膨胀套管轴向长度的变化规律也不同：上约束方式下,套管长度先略有减少后稳定增加;下约束方式下,轴向长度一直减少。该规律通过对Φ95 mm套管的实际旋转膨胀试验得到验证,证明了模拟情况的可信性。

Finite Element Analysis on the Rotating Expansion of Expansion Tubular in Different Constraint Methods

Based on the analysis on LS-DYNA dynamic finite element,rotating fitting expansion tubular model was established with the whole expansion process simulation.By the analysis on stimulation results of different constraint methods to the tubular,it was found that the swelling force required in rotating fitting expansion is 1/5 of that in reverse tensile of solid cone;and change rule of axial length of the expansion tubular was variable in deferent constraint methods： with upper constraint method,the tubular length was a little decreased at first,and then steadily increased;while with underneath constraint method,the tubular length decreased all the time.This rule was proved by the rotary expansion test on 95mm tubular,the simulation was credible.