1) Material problem of the main working parts of the mold, improper material selection. Material performance is poor, not wear-resistant; Die steel is not refined and there are many smelting defects; The forging process of punch and die and forging blank is not perfect, and there are hidden dangers of heat treatment.

2) The mold structure design problem, the mold structure is unreasonable. The slender punch is not designed with reinforcement device, and the poor discharge port leads to accumulation, and the excessive discharge force makes the punch bear alternating load.

3) Imperfect die-making process is mainly manifested in poor internal quality of the punch and die forgings, and problems in heat treatment technology and process, which lead to incomplete quenching of the punch and die, soft spots and uneven hardness. Sometimes micro-cracks or even cracks appear, the grinding and polishing are not in place, and the surface roughness value is too large.

4) No lubrication or lubrication, but the effect is not good.