495A柴油机齿轮罩原设计用ZL12铸造铝合金,由于铸造中产生缩孔等缺陷,废品率较高。因此,我们改用了冷冲件,经过一年多生产实践,取得了良好效果。 1.零件结构和工艺过程 零件结构如图1、2。改进前工艺较简单,铸造后进行切削加工。改进后采用1.5毫米厚的08钢板,经落料、拉延成形、整形、切边、冲孔、翻边等六个冲压工序,最后镀锌。其中较关键的工序是拉延成形(图3)。拉延 495A diesel engine gear cover original design ZL12 cast aluminum alloy, due to shrinkage defects such as foundry casting, rejection rate higher. Therefore, we use the cold stamping parts, after more than a year of production practice, and achieved good results. 1. Parts structure and process parts structure shown in Figure 1,2. Before the improvement process is relatively simple, cutting after casting. After the improvement of 1.5 mm thick 08 steel, the blanking, drawing forming, shaping, trimming, punching, burrs and other six stamping process, and finally galvanized. The more critical process is draw forming (Figure 3). Draw