平面变曲率管件成形工艺获取策略研究

目的 获取平面管件在弯曲成形过程中的初始工艺参数。方法 基于平面圆弧管件弯曲成形原理，将成形管件划分为稳定段和过渡段。针对稳定段，分析了平面圆弧管件的弯曲半径与弯曲模偏移量之间的映射关系，并通过二次曲线拟合得到非线性方程，以方便预测管件稳定区的成形工艺参数;针对过渡段，通过分析不同时间内不同模式下弯曲模偏移量对整体管件成形的影响，以确定最佳过渡方式。基于管件成形工艺知识库，提出了平面管件弯曲成形工艺参数的规划与预测方法，并通过成形实例管件进行了验证。结果 整个管件的逼近残差为0.230 1 mm，最大偏差为0.390 7 mm，逼近残差和最大偏差与管件总长度的比值分别为0.127 4%和0.216 2%。结论 所提出的方法可以有效获取平面变曲率管件的成形工艺参数。

Acquisition Strategy of Forming Process of Flat Variable Curvature Pipe Fitting

The work aims to obtain the initial process parameters of flat pipe fittings in bending forming. Based on the bending forming principle of flat arc pipe fitting, the forming pipe fitting was divided into stable section and transition section. For the stable section, the mapping relationship between the bending radius of the flat arc pipe fitting and the bending die offset was analyzed, and the nonlinear equation was obtained by quadratic curve fitting to facilitate the prediction of the forming process parameters in the stable section of the pipe fitting; For the transition section, the optimal transition mode was determined by analyzing the effects of the deflection of the bending die in different modes on the forming of the integral pipe fitting. Combined with the above analysis, based on the knowledge base of pipe fitting forming process, a method for planning and predicting the process parameters of flat pipe bending was put forward and was verified through forming simulation. The approximate residual error of the whole pipe fitting was 0.230 1 mm, the maximum deviation was 0.390 7 mm, the ratio of the approximate residual error and the maximum deviation to the total length of the pipe was 0.127 4% and 0.216 2% respectively, It is verified that this method can effectively obtain the forming process parameters of flat variable curvature pipe fittings.