EVA foaming--three major processes

EVA foaming in general there are three kinds of technologies, the traditional large-scale foaming plate technology, in-mold small foaming technology and injection process.

1, Injection process
This process will slowly become the mainstream, a process produce the products, easy and concise, but the mold is relatively high precision. Process principle is similar to the plastic injection molding industry, but the injection mold is opened immediately, and the mold temperature is different, EVA injection is to plastic injection mold temperature and mold opening time has been adjusted. Now most well-known sports shoes are used this method. high efficiency!

2, The traditional large flat foaming technology
Now smaller factories generally use this process, the cost of machinery and equipment is relatively low. This process is mainly used as a plate, and then made by blanking, edging and other processes products. Foaming conditions are relatively fixed, the temperature at 160 ~ 170, the time determined by the thickness of the mold, the general 90 ~ 110 seconds / MM, pressure 150KG / square CM.

3, In-mold small foam process
This process is mainly used in shoe materials, sports shoes to do the first time in the end of the foam. According to recipe good material granulation, into a good mold, foam out is the general look. The difficulty is the symmetry of the mold and the formula, otherwise it is difficult to control the magnification and hardness. Often the size is ok but the hardness is not enough, the hardness is ok but the size is small. Foaming conditions more flexible, depending on the product structure, of course, mainly the impact of time.