1.碗形零件拉延凹凸模的负间隙值文献推荐(不变薄)拉延的凹凸模间隙值,应比材料名义厚度(t)稍大些,其单边间隙值为1.0～1.3t,以便有利于材料进入凹模和减少摩擦力。其中有的资料还明确指出:这样的间隙值不仅适用于不精密的拉延件(7、8级精度),而且还适用于较精密的拉延件(4、5级精度)。 1. bowl-shaped parts drawing die negative clearance value Recommended (not thinning) Drawing die punch gap value should be slightly larger than the nominal thickness of the material (t), the unilateral clearance value of 1.0 ~ 1.3t , In order to facilitate the material into the die and reduce friction. Some of the information also clearly pointed out: This gap value not only applies to inexact extension of the drawing (7,8-level accuracy), but also for more sophisticated drawing parts (4,5 precision).