Going to a mobile phone stamping die factory to learn precision die technology, I feel the deepest is not its superb die design level and precision processing technology, but its precision die development concept.

The next day, the group leader told us to instill a precise concept of mold. What is the concept of precision die? I don't think so. All the products here are thin materials. I've done some before. Why don't I have a precise idea?

With the gradual deepening of learning, I began to realize my superficiality!

The first stop of our trip is high-speed module building. Regarding the precision of the die, the high-speed terminal die should be considered as the most precise one here. Stainless steel and aluminium materials with punching materials ranging from 0.08 mm to 0.2 mm are generally used. The blanking clearance is as small as 0.008 mm and the minimum width of punching holes is 0.25 mm. The punch looks like a kind of weak wind-proof feeling. How to punch such a small hole? How can such a small blanking gap ensure the manufacturing accuracy of the die? It's hard to imagine it without seeing it with your own eyes.

It is not difficult for us to feel the pulse of this set of dies by turning over the drawing surface, understanding the die structure, designing and manufacturing tolerances and its special manufacturing process.

All piercing parts are lumped and punched from top to bottom with tungsten steel blade. JG grinding of the entry holes and fixed pin holes of the upper template, stripper and lower template, sliding fit clearance c+0.005~0.010 mm, non-sliding fit c+0.003 mm, and processing accuracy +/-0.002 mm; the main structure guide part is ball sleeve with precision guide pillar, and the punching hole structure adopts local structure separated from the upper die, and the lower template is locked with equal height sleeve. On the other hand, the accuracy error of stamping equipment is compensated; the guide parts of local structure are precise graphite self-lubricating inner guide pillar, stripper and inner guide sleeve of lower template are glued to compensate the processing error of guide parts and improve the guiding accuracy so as to ensure the position accuracy of template in stamping process; the punching stroke as small as possible can make punching hole. The length of the punch should be as short as possible. Appropriate punch reinforcement can improve the strength of the punch. Thus, it can fully embody the design concept that die designers tend to be highly precise, and ensure the high quality and high requirements of the die as far as possible.

Modern processing equipment, high precision processing technology, but also make these design concepts to be allowed to play. After heat treatment, the formwork is subjected to cryogenic aging treatment to eliminate internal stress, prevent the deformation of the formwork, ensure the processing stability of the formwork, and ensure the flatness and parallelism of the formwork by plane grinding with a parallelism of 0.005 mm.

I admire the precision of the die set up engineer. First, carefully understand the surface of the die, familiar with product information, analyze the die structure, understand the design intent; check parts, chamfering, polishing, engraving and mark meticulously; deburr template, oil and rust-proof step by step, install external guide pillar and guide sleeve with special positioning tools to ensure its verticality; fourth, the actual thickness of the template is measured. Point measurement difference within 0.005 mm is qualified; punch and block single matching, smoothly matching, degree of grinding, clear judgment standards; self-inspection of products during mould testing and mode adjusting should use projector, accurate to 0.003 mm when repairing the module; without precise concept, it is impossible to cultivate high-quality, and also impossible to install high-precision mould.

Mold development is mainly divided into three stages: die design; die processing; die set-up, test and repair. All three are indispensable. A set of high precision die should have precise design, precise processing, and precise assembly.

The designer gives the soul of the mould, the processor casts the body of the mould, and the organizer gives the mould life. Precision die concept runs through the whole process of die manufacturing. The inheritance of ideas from top to bottom, from the master to the apprentice, good habits become natural, it is not difficult to imagine which one of the birth process of fine mold. To cultivate the concept of precision mould should be the key content of my study, to learn the good habits of others, to develop their own good habits, to establish ideas, and to integrate into the work.