• 2023-10-30
• 289
• 5 Comments

The fixed mounting method of the die punch

The installation of the die punch is carried out on the die punch fixing plate, and there are two requirements for positioning and fixing. The positioning of the die punch is achieved through the combination of the die punch and the hole in the fixed plate, and the fixing can be completed by hanging shoulders, bolts, riveting, epoxy resin glue, side pins, cross pins and pressure plates. Because of the irregular shape of the straight-through die punch, a cuboid die punch insert needs to be added at the installation site to assist. There is a certain distance between the punch position of the fixed plate and the working position of the punch edge of the die, which is easy to cause the punch instability of the die and cause failure. If the punch edge size of the die is small, it is impossible to normal mass production. When the die punch is made into a press plate and fixed, a discharge insert is added. When the die punch passes through the discharge insert and the die is blanked, the discharge insert can guide the die punch into the die and protect the die punch from lateral force. The unilateral gap between the punch and the discharge insert of the die is designed to be 0.003 ~ 0.005mm or even smaller, and the discharge insert is exposed about 3mm when the punch of the die is working, which is not easy to be damaged. The size of the mounting part of the mold punch is designed to be consistent with the square hole size of the fixed plate or slightly smaller, and the press slot is 0.02 ~ 0.05mm lower than the fixed plate, so that the mold punch has a little room for activity in the fixed plate, and the real positioning depends on the discharge insert to avoid the positioning of the fixed plate and the discharge insert. Because the location of the discharge insert is the working position of the punch edge of the die, the effect is best. The die punch can be removed by removing the screw and pulling out the die punch. The die punch is easy to disassemble and can realize the fast maintenance and repair of the die punch.

2.3 Material selection of die punch

Die punch should be able to withstand a certain impact force, but also have a high wear resistance, so should choose a high hardness material with a certain toughness. Continuous precision stamping die in order to meet its mass production capacity, in the mold punch material selection is the best of the best. Cr12MoV, Cr12 and SKD11 and other commonly used die punch materials in the continuous precision stamping die can only be used to make templates or inserts, continuous precision stamping die punch the most commonly used material is foreign tungsten steel CD650, its surface quality is high, very wear-resistant, the best use of hardness up to 90HRA; The second is the foreign high chromium molybdenum vanadium powder material ASP-23, the best use of hardness of about 63HRC [3].

2.4 Processing method of die punch

Straight mold punch shape is irregular, generally using slow wire cutting processing, cutting a repair one or two, slow wire cutting although the processing accuracy is high, but the surface high temperature generated thin oxide layer will also affect it, can achieve a dimensional accuracy of ±0.003mm. The shoulder punch is processed by an ordinary Xiaoping grinder (G), and it is necessary to pay attention to the shoulder design in a position that does not affect processing. The punch of the reinforcing mold is processed by optical grinding machine (PG), which has high cost. The dimensional accuracy of the latter two can be achieved with ±0.002mm.

Closing remarks

Continuous precision stamping dies have high requirements for die life, and the life of electronic communication hardware stamping dies generally needs to reach 100kk (100 million) strokes, while the life of the terminal die needs to reach 500kk (500 million) strokes. Die punch design needs to consider the product accuracy, production program, die life, processing difficulty, easy maintenance and economic performance and other factors, according to the actual situation of the correct, reasonable and flexible design of the die punch, to meet the product quality requirements, conducive to timely improvement and ensure smooth production