用冲孔模冲小孔,冲头很容易損坏。損坏的原因很多,主要是在冲孔时由于压力的作用,使冲头的工作部分弯曲而折断;特别是冲制坯料厚度和孔徑的比值大以及多孔的工件,更容易发生这种情形。图1表示用一般結構的冲孔模,冲制坯料厚度和孔徑的比值很大的工件,冲头发生弯曲的情形。 Punching small holes punched, punch is very easy to damage. There are many reasons for the damage, mainly due to the pressure acting on the punching part to bend and break the working part of the punching punch. In particular, it is more likely to occur when the ratio of the thickness of the punching material to the hole diameter is large and the porous workpiece is porous. Fig. 1 shows a punching die of a general construction in which a workpiece having a large ratio of the thickness of a billet and an aperture is punched out and a punch is bent.