What is the reason for the explosion of the metal stamping die?
First, choose the press
In order to prolong the service life of the metal blanking die, a high-quality punch should be selected. The average regrind life of the open press is 10,000-30,000 times, while the die life of the new precision press can reach 60,000-12,000 times. Especially for dies with small or no gaps, cemented carbide dies and precision stamping dies, presses with high precision and good rigidity should be selected, otherwise the service life of the die will be reduced, and the die will be damaged in severe cases.
2. Reasons for mold design
Usually, if the structure is unreasonable, the strength is insufficient, the distance between the knife edges is too close, the number of template blocks is insufficient, or there are no feet, etc., the mold will have a great risk of bursting. The mold design mainly includes the following:
1. Nesting and lap joint: The reciprocating feeding method often leads to damage to the mold, and the lap value is too small, which aggravates the wear of the mold. Therefore, choosing a reasonable layout method and overlapping boundary values can prolong the life of the mold and avoid the situation of mold explosion.
2. Guide rail accuracy: The guide rail has high precision and reliability, which can reduce the wear of the guide rail and avoid the gnawing of the convex and concave die. Especially suitable for no gap, small gap blanking, compound, multi-station progressive die. In addition, according to the characteristics of the processing technology and the accuracy of the parts, choosing the correct form of guide and the accuracy of the guide mechanism is the key to improving the service life of the mold.
Third, the reason for the processing technology
The experimental results show that the thermal processing quality of the mold has an important influence on its performance and life. According to the analysis and statistics of failure causes, more than 40% of mold failure accidents are caused by improper heat treatment. In the manufacture of blanking die, improper quenching and tempering process will cause deformation of the finished product and eventually cause the die to burst.
1. Preheating heat treatment: According to different mold materials and requirements, operators should adopt preparatory heat treatment methods such as annealing, normalizing, and quenching and tempering to eliminate structural defects in forgings and improve the level of processing technology. In addition, proper preheating of the mold raw materials can make the carbide distribution more uniform, which is beneficial to ensure the quality of quenching and tempering, and prolong the service life of the mold.
2. Quenching and tempering: This is an important part of mold heat treatment. If the quenching temperature is too high, the brittleness of the mold will be strengthened, which will cause the product to be easily deformed and fractured during the cooling process, which will seriously affect the service life of the mold. Quenching and heating must be carried out in strict accordance with the heat treatment process regulations, with particular attention to oxidation, decarburization and other phenomena. If conditions permit, vacuum heat treatment can be used. In addition, tempering should be carried out in time after quenching, and different tempering processes should be selected according to technical requirements.
4. Surface strengthening treatment
In order to improve the performance and life of stamping dies, the surface strengthening treatment of die workpieces is more and more widely used. Common surface strengthening methods are liquid carbonitriding, ion nitriding, boronizing, vanadium and spark strengthening, chemical vapor deposition (CVD), physical vapor deposition (PVD), carbide immersion in a salt bath (TD) In addition, surface strengthening treatments such as high-frequency quenching, hydraulic pressure, and shot peening can generate compressive stress on the surface of the mold workpiece, improve its fatigue strength, and help prolong the service life of the mold.
The above is the content related to metal stamping dies. The selection of stamping equipment is directly related to a series of important issues such as equipment safety, production efficiency, stamping quality, punching die life and production costs. Therefore, careful selection is required. Hope the above content can be helpful to readers.