When designing plastic injection molds, there are several factors to take into consideration including the molding environment in which the tool will run. Of the utmost importance in mold design is the injection molding press specified for the production operation.
Some presses have either a vertical or horizontal clamping system. A vertical clamping system is typically used for shuttle molds, also referred to as insert molds, and is used for molding plastic around an insert usually made of plastic or steel. The clamping system will open, allowing an operator to place an insert in the bottom half of the mold, prior to closing allowing plastic to flow around the insert. This process is used to put a plastic or rubber like coating around an object such as knives for example, or electrical wiring harnesses requiring a housing to fit around a wire assembly. Shuttle molds for vertical clamping presses will have at least two bottom (B) halves so that the molding is occurring on one side of the press while an operator is loading inserts on the open side. This allows for maximum production even when an operator is required.
The typical injection mold will have a horizontal clamping system, opening on a horizontal plane and allowing parts to fall below into a bin or straight onto a conveyor belt when ejected. Some horizontal molding operations are fully automatic and do not require an operator, once the mold is set in the press and proper parameters are set. This is a very efficient method of molding, and several molders utilize this type of operation in a lights out automatic environment. This, of course, requires a quality crafted precision tool to ensure a consistent molding process.
The placement of water fitting and hoses is also of equal importance, as these lines cannot be in the way of the mold operating in the press. The tonnage and clamping pressure of the press is needed when designing the mold, and the barrel capacity is required to ensure production requirements can be met. Download a FREE copy of our book “Design Considerations for Different Molds” for more information.
Michiana Global Mold has over 500 years of combined experience designing and building precision custom molds for various industries. Contact us today to speak with one of our knowledgeable engineers for a free quotation on your mold building requirements. We can custom design molds for your applications, regardless of your molding environment.