Injection Molding
Services

Injection molding is the process of injecting molten plastic into a mold cavity, rapidly cooling it, then ejecting the solidified plastic part. It is the most widely used manufacturing process for plastic parts and the most affordable route to mass production. Once the metal mold or tooling has been made, hundreds, thousands, or millions of plastic duplicate parts can be made in a short timeframe, with the effective cost-per-part reducing with each additional molding as the cost of the mold is amortized. Injection molding is compatible with a very wide range of materials — including thermoplastics, thermosets, and even metals — which can be easily mixed with color pigments and other additives to tweak the function and appearance of the moldings. Furthermore, the injection molding process offers excellent consistency between units, as the tooling remains constant throughout.

At 3ERP, we offer a range of injection molding services, from affordable low-volume prototyping to part production, using thermoplastics, thermosets, or metals. Our team of experienced molding specialists can guide you to the right solution, whether you need rapid aluminum tooling for a fast prototype or a more durable solution for larger production runs. Unlike many molding companies, we do not specify a minimum order quantity.

Injection molding uses an injection molding machine made up of three sections: the injection unit, the clamping unit, and the mold or tooling. Such machines are large, expensive, and require expert operators.

During the injection molding process, plastic material in the form of small pellets or granules is fed into a large hopper. The machine moves the pellets from the hopper to a heated barrel, where they melt down into a liquid. Within the barrel, a reciprocating screw — which functions as a kind of plunger — pushes the molten plastic towards the check valve. When enough material is ready to be injected, high pressures are applied, and the material is forced into the mold through a network of channels called sprues and runners. The plastic solidifies, taking the shape of the mold cavity, and is then ejected from the mold with the aid of ejector pins. The process then repeats, with cycle times ranging from a few seconds to upwards of a minute.

When ordering custom injection molding parts from 3ERP, we will first review your design and send a quotation. When quantities and pricing have been agreed, we will quickly fabricate the tooling and, if required, send a sample molding before starting production.