前副车架上板冲压工艺及拉延模设计

Stamping process and drawing die design of upper plate for the front subframe

汽车前副车架上板料厚3.5 mm,型面变化复杂,有多处凹凸面,装配孔与其他零件装配精度要求高,零件成形难度较大。制定了五工序的冲压工作内容,其中拉延为最重要的成形工序。其工艺方案的关键技术是采用工艺凸包,防止转角在拉延时开裂。针对前副车架上板的材料厚度大、形状复杂、材料流入困难的问题,在内外压边圈均不设拉延筋,使成形得以顺利进行。应用Auto Form软件对前副车架上板进行成形仿真分析,通过多次调整压料面、工艺补充面、圆角、板料外形、压边力,得到了优化后的拉延工艺数模,并生产出质量合格的产品,验证了冲压工艺改进的有效性。

The upper plate of car front subframe of 3.5 mm thickness has complicated variation and contoured surface, and it is difficult to form because the assembly accuracy requirement between assembly hole and other parts is high. In the design, five processes of stam- ping were formulated, and the drawing process was the most important forming process. Its key technology was to adopt the craft convex hull to prevent cracking from the corner during drawing process. For the problems of large thickness of material, complicated shape and difficulty in inflowing of material for upper plate of the front subframe, the drawbeads were not set on the inside or outside blank bolder, so that the forming can be carried out smoothly. The forming process of upper plate was simulated by AutoForm software, and the opti- mized drawing process model was obtained through adjusting the binder surface, addendum surface, rounded, sheet shape and blank hold- er force repeatedly. Therefore, the qualified products were produced, and the effectiveness of stamping process improvement was verified.