凸环管件颗粒介质内高压成形工艺理论解析

离散体颗粒介质使颗粒介质内高压成形工艺中的传压具有非均匀性、颗粒介质与管件之间摩擦作用显著等特征,基于此，建立了颗粒介质非均匀载荷传压模型，对凸环管件胀形工艺过程进行了理论推导和数值解析，探讨了内压状况和摩擦条件对管件成形性能的影响，并通过工艺试验对理论分析结果进行了验证。分析结果表明，颗粒介质内高压成形工艺所具有的内压非均匀性、介质与管坯摩擦作用显著两大特征可有效减小胀形过程中的壁厚减薄和成形压力。对比试验与理论分析结果表明，壁厚分布和成形压力的理论计算结果与试验结果一致，颗粒介质非均匀载荷传压模型的构建策略可用于管件成形的预测和分析。

Theoretical Analyses of Tube Granule Medium Internal High Pressure Forming Processes

The discrete granules brough a non-uniform internal pressures and a significant friction between tube and medium to granule medium internal high pressure forming processes. Therefore, a non-uniform pressure transfer model was built for this process to investigate into theoretical analyses of tube bulging. The effects of the non-uniform pressures and the significant friction on tube forming property were studied by the theoretical analyses which were verified by processing tests. The analyses show that the non-uniform pressures and the significant friction may reduce the thickness reductions and forming pressures of tube bulging. The comparison of theoretical analyses and processing tests indicates that the calculated curves of thickness distributions and forming pressures agree well with test results. The non-uniform pressure transfer model for granule medium internal high pressure forming process may be used for the predictions and analyses of tube forming processes.