How to determine the optimal number of cavities for injection molding molds?

The cavity number of injection molding mold will not only affect the manufacturing cost of the mold, but also affect the manufacturing cost of injection molding products, so it is very important to decide the cavity number of injection molding mold. The following is based on many years of experience in the injection mold industry from the injection molding processing cost and injection mold design and manufacturing technology of the difficulty of two aspects to tell this problem.

I. Injection molding processing cost considerations:

1. Monthly output and annual output, generally speaking, the larger the output is, the more the number of mold cavities are required. The specific number can be calculated according to the number of injection molding products every day.

2. Specification of injection molding machine

The number of cavities of the injection mold may be different from the model of the injection molding machine. Normally, the mold with more cavities needs to choose the injection molding machine with larger tonnage for injection molding.

3. Injection mold structure

The more cavities needed to form the part, the longer the pressing time. Longer pressing times limit the ability to produce parts quickly, thus increasing costs. Producing a large number of parts requiring a large number of cavities will also involve higher production costs.

4. Injection mold maintenance cost

Two. Factors to consider the difficulty of injection mold design and manufacturing technology:

1. The cavity filling is balanced

The more cavities the injection mold has, the more difficult it is to ensure the balanced filling. From the analysis of rheology, the different shear rates of the inner layer and the outer layer lead to the temperature difference. Therefore, the more cavities the better, the more can meet the production demand.

2. Size, appearance and weight errors of molding products

With the increase of the number of cavities, each cavity molding product size, weight, appearance and other quality will have a great difference trend, must consider the advantages and disadvantages of the cavity number must be decided.

3. Size changes caused by thermal expansion of the mold

Usually, when the temperature rises, the metal thermal expansion occurs, and the parts of the injection molding mold thermal expansion also occurs, which will lead to: affecting the coordination of the guide column and guide sleeve, the sliding block of the side core withdrawal is not smooth, and the size of the core expansion. In the case of multi-cavity mold, the size change of each cavity is not the same, so it will affect the size of the injection product.

4. Uneven temperature distribution of injection mold

The uneven mold temperature distribution directly affects the texture uniformity and dimensional accuracy of injection molding products, and it has a greater impact on the multi-cavity mold. The influence of mold temperature on the quality and output of injection molding products is very great.

The number of cavities of injection mold can not be decided at any time. There are many influencing factors that must be considered. In particular, the optimum number of cavities of mold must be determined by comprehensively weighing the cost of molding and the difficulty of mold design and manufacturing technology. The mission of Fanstar is to master the core technology of injection molding production, communicate and analyze the technology before mold production with customers from the production needs of finished products, so that the mold delivery time is short, the service life is long, the rapid mass production and the finished product quality is excellent! Welcome to contact us if you need injection molding!