When designing a set of injection mold cavity number should be identified first, only the cavity number, into the next phase of work. If it's purely from the plastic parts quality, single cavity mould of the highest quality, but, injection time, it can only produce a product, low efficiency, high cost, therefore, in actual production, people often adopt multi-cavity mold. The general method to determine the cavity number has the following several.

1. According to the injection molding machine injection molding capability. 2. According to the injection molding machine clamping force. 3. According to the precision plastic forming parts. 4. According to the production of economy.