新型管材冲击液压成形装置的设计

针对常规的管材液压成形技术需要昂贵的专用设备及模具、生产效率低等不足,开发了一种简单实用、可在冲床或压力机上使用的管材冲击液压成形装置,可用于薄壁金属管材的自然胀形、轴压胀形和异形截面中空件的冲击液压成形。该装置无需外部高压供给系统和专用液压成形设备,通过撞击轴压头挤压容腔中液体的方式来为管材提供液压力和轴压力。通过设计轴压头的行程和调节溢流阀的溢流压力值等来实现最大液压力和轴向进给量的合理匹配,并以304不锈钢毛细管和H65黄铜毛细管为试验管材做了相关试验。研究结果表明:该装置结构简单、操作方便;可实现最大液压力与轴向进给量的协调控制;合理的载荷匹配能显著地提高管材冲击液压成形的成形性能;H65黄铜毛细管破裂时所需的液压力小于304不锈钢毛细管破裂时所需的液压力。

Design on a new type of tube impact hydroforming equipment

For the problems of conventional tube hydroforming requiring expensive special equipment and die with low production efficiency,a simple and practical device was developed as tube impact hydroforming equipment used on a stamping press or press machine.This new device could be applied to the spontaneous bulging,the axial force bulging and the impact hydroforming to manufacture hollow parts with various cross-sectional area of thin-walled metal tubes.Without the external high pressure supply system and special hydroforming equipment,the internal hydraulic pressure and axial force on the tube could be obtained automatically by extruding the liquid in a chamber through impacting the axial compression head,and a reasonable matching between the maximum hydraulic pressure and axial feed could be achieved by properly designing the axial compression head and the overflow pressure value of relief valve.Furthermore,the relevant test was done by 304 stainless steel capillary and H65 brass capillary.The primary experimental results show that the device has characteristics of simple structure and convenient operation,and it can realize a coordinated control between the maximum hydraulic pressure and the axial feed.However,the forming ability of tubes is improved greatly under a reasonable load matching,and the hydraulic pressure of H65 brass capillary rupture is lower than that of 304 stainless steel capillary rupture.