1) improper selection of materials for the main working parts of the mold. Poor material performance, not wear-resistant; Die steel has a lot of smelting defects without refining. The forging technology of convex and concave die and forging billet is not perfect.
2) the problem of die structure design and unreasonable die structure. No reinforcing device is designed for the slender punch, and the discharge port is not smooth, and the unloading force increases the pressure on the punch to bear the alternating load.
3) imperfect die making process, mainly manifested in poor quality of convex and concave die forging billet, and problems in heat treatment technology and process, resulting in impervious quenching of convex and concave die, with uneven soft points and hardness. Sometimes produces the micro crack, even the crack, the grinding polishing is not in place, the surface roughness value is too large.
4) no lubrication or lubrication but poor effect.