About the number of mold cavities

 The number of cavities that can be processed by one injection in a plastic molding mold is called the number of cavities.

In the actual application records, the number of cavities is at least 1 and at most 192.


The higher the number of cavities, the higher the number of molded products per injection, thus reducing the production cost per part.

However, as the number of cavities increases, there is a tendency that there will be great differences in the quality of molded products such as size, weight, and appearance of each cavity.

The number of cavities must be determined after comprehensive consideration of advantages and disadvantages.


In general, the number of cavities tends to be as follows depending on the type of mold.


¡ Large molded products...basically a single cavity


reason


The mold is large, so it is physically difficult to set more than 2 cavities.


 


¡ Small and medium-sized molding products such as automobiles and home appliances... about 4 to 8 cavities


reason


Considering the relationship between total production quantity and quality deviation, empirically, this number of cavities has a low risk.


 


¡ Electronic components, precision components...a mold with 2 cavities or 4 cavities


reason


Pay attention to the quality deviation of molded products and decide to use fewer cavities.


 


¡ Food containers, etc. 24 to 64 cavities or more per mold (hot runner specification)


reason


Production quantities of a few million pieces or more are expected, so the higher the number of cavities the lower the production cost.


 


¡ Mold for new product...single cavity


reason


Since the sales volume of new products in the market is still uncertain, a single-cavity mold will be opened first. If the sales situation is good, a multi-cavity mold with an increased number of cavities will be opened for production.

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