汽车转向节精锻工艺设计与锻造主机选型

Design on precision forging process of automobile steering knuckle and selection of forging main press

典型异形转向节的轴径细长、截面形状差异较大,由于具有负拔模角,主要采用卧锻成形方式,而现有的卧锻成形工艺产品质量难以保证,并增加了自动化生产的困难。针对该异形转向节的结构特点和成形难点,提出了由"镦粗—压扁—预锻—终锻"4个锻造工序构成的异形转向节精锻工艺,并对该工艺进行了模拟仿真。模拟结果显示:镦粗和压扁工序将材料进行了预分配,为细长的轴杆部和粗大的盘部和叉形件处提供了后续成形的材料量;预锻和终锻工序分别完成锻件的主体锻造以及圆角和局部的充填,工艺设计合理,锻件填充饱满。依据模拟分析结果,并结合锻造工序与压力机的设备特点,提出了适应该类转向节自动化锻造生产的主机类型和主机吨位。

The typical special-shaped steering knuckle has a slender shaft diameter and a large difference in cross-sectional shape.Because of the negative draft angle,the horizontal forging method is mainly used,and the existing horizontal forging process is difficult to ensure the product quality and increases the difficulty of automatic production.Therefore,for the structural characteristics and forming difficulties of this special-shaped steering knuckle,the precision forging process of special-shaped steering knuckle consisting of four forging processes of upsetting,flattening,pre-forging and final forging was put forward,and the process was simulated.The simulation results show that the upsetting and flattening processes distribute the materials in advance,which provides the amount of material for subsequent forming of slender shaft part,thick disc part and fork-shaped part,and the pre-forging and final forging processes respectively complete the forging of the main part of forgings,as well as the fillet and partial filling of forgings,indicating that the process design is reasonable and the forgings are fully filled.In addition,according to the results of simulation analysis,combined with the forging process and the equipment characteristics of press,the type and tonnage of main press suitable for automatic forging production for this kind of steering knuckle were proposed.