Analysis of common problems in the processing technology of EVA foam die-cutting parts

Hypotenuse problem

First of all, regarding the beveled edges that are prone to occur in the die-cutting and punching process, the reason for this problem is that the thickness of the foam is high. In the punching process, the foam is extruded and cut after the foam is extruded. Beveling, the main method for solving such problems is to change the choice of tools.

Usually the die-cutting tool we use is a double bevel cutting tool for punching operations. So here to ensure effective reduction in the generation of beveled edges, we use a single-edged knife to punch the inner straight and the outer bevel, which can effectively reduce the generation of foam beveled edges.

At the same time, for the relatively simple structure of EVA foam die-cutting parts, we use slitting, edge splitting, and skip cutting to reduce the factor that affects the beveling, so as to avoid the beveling problem. For some products with a slightly complicated structure, we can use the method of knife line decomposition to punch, instead of closing the knife line, and multi-wire overlap, to reduce the extrusion stress during the foam punching process, so as to reduce the foam skew. Side issue.

Debris dust

Secondly, with regard to the problem of EVA foam debris and dust, the root cause of this problem lies in the characteristics of the foam itself. Due to the low toughness of the foam, the composition structure is a foam material. All in the punching process, because The repeated action of the knife makes the debris foam particles easily form dust and float in the air. For some die-cutting operations that require cleanliness, there are many ways to solve such problems. The common method is to spray a release agent. The method often used on the production line is to laminate an OPP protective film on the surface of the EVA foam. Solve this problem. Of course, this solution may cause some waste of auxiliary materials.

Difficult to eliminate waste

Thirdly, regarding the difficulty of discharging waste with porous waste, in fact, the most fundamental reason for this kind of reason is that the foam is too thick, and at the same time, the small hole diameter causes the waste to be difficult to extract in the process of discharging. The general traditional method is to make a set of thimble fixtures outside the die base of the die-cutting machine to discharge waste. The hole-shaped waste is ejected through the thimble, and the falling material is discharged. However, this kind of waste discharge method is not easy to operate, and it is easy to scratch the foam and cause product failure. The commonly used method on the round knife is the extraction knife for extraction and waste disposal. Today, for the occurrence of such problems, the editor gives a better job plan, which is an asynchronous job plan.

Solution-on asynchronous job

Fourth, the benefits of the upper asynchronous job program; as everyone knows, the upper layer material is asynchronously pulled and the lower layer material is synchronously die-cut to achieve the purpose of saving materials. Here, we use the asynchronous method to separate the foam and the backing film to pull the material, which not only saves the foam material, but in the actual operation process, the upper layer of material is taken away at the same time, the foam outer frame waste It is also taken away at the same time, and due to the effect of stress, the hypotenuse will also be greatly improved. Furthermore, through this method of operation, the basic dust problem has also been effectively solved.