Injection molding can be used to create parts for any purpose. Parts can vary in size and shape, depending on what they will be used for. Plastic is the most common material for injection molding (and the most cost-effective), but rubber or metal materials may also be used. Micro-injection molding is currently desirable because it allows companies to save money by building smaller parts. It is also becoming more common because equipment tends to miniaturize as technology advances.

Injection Molding Considerations

When considering injection molding, companies can choose to order bulk amounts of standard parts, or to create custom orders. Custom molding is typically used when companies need parts to match exact specifications. Parts that are often customized include poppets, connector seals, piston seals, lip seals, bushings, diaphragms, and molded inserts. Custom parts are generally more expensive than purchasing standard molded parts.

Mold design is very important in the injection molding process. For instance, uniform wall thickness is necessary to prevent warping, shrinking, breaking, or stresses to parts over time. Companies can lower costs by minimizing the wall thickness of molded parts. Minimizing wall thickness allows for rapid cooling and short cycle times. Costs can be saved through tooling methods, materials, and the size or weight of products as well.

To improve part stiffness in bending, ribs or gussets may be used. This method saves on the costs of materials, weight, and cycle time because it helps companies to avoid using thick molded sections instead. Another method to consider when designing molds is using rounded corners so that parts are easy to remove from their molds. Therefore, they will not suffer from added stress as they are removed and they will be more durable as parts.