As with dip molding, a liquid or melted plastic is used in the injection molding process. Likewise a mold is a required element of the process. The melted plastic is injected into the mold at a high pressure and the mold itself is constantly cooled so that the heated material will adhere to the cavity walls forming the part. As the process finishes, the mold opens and ejection pins within the mold eject the newly formed part from the mold.
The mold or mold plates are actually two pieces or two halves of a whole. Each half contains at least one cavity and often more than just one. Molds are typically made of metal, usually steel or aluminum, but the choice is often based on the economics. Steel costs more, but lasts longer. Aluminum costs much less, but does not carry as long a lifespan. The size of the mold, the number of cavities, anticipated tool longevity all factor in on the cost of a mold. Watch now to see a brief overview of the process.
Materials – Low-density polyethylene is the most common material used in the production of our injection product lines. PVC is primarily used to manufacture injection molded hand grips. There are many other materials used in the process and since the use of injection molded parts is so widespread, ranging from combs, toys, electronic housings, body panels of automobiles and appliance parts, the choice of material is dependent on the end use.
Engineering and Prototypes – When we receive your specifications, our engineering staff utilizes their expertise to explore all possibilities in determining the best material and the best process for the project. Our engineers have designed parts ranging from our standard styles to more complicated engineered custom parts made to solve some of the most difficult problems. Within the scope of our injection molding process alone, we have developed thousands of parts. Our goal is to design your part in the most cost effective manner and to design it to deliver the highest level of performance required.
Not only do we have over 50 years of design experience, but we utilize some of the most sophisticated design and manufacturing software. We've grown in CAD CAM technology beginning in the early years of AutoCAD, then Pro-Engineer software. Collaborating with all our locations, we work seamlessly using PTC Creo and Siemens NX programs to seamlessly integrate the tooling fabrication process.
We are able to provide prototypes for engineering and marketing tests and, although technology has improved the precision-machined process used in forming molds, prototypes can still take time and usually come with a price.
Equipment – Various styles of machines or presses hold the mold during the process. Injection molding presses are rated by the amount of pressure the machine is capable of exerting on the molds which keep them closed during the injection of the heated materials.
The mold plates are mounted onto the machine, or press, and the material is injected into the mold flowing into the cavity through various channels called runners. The heated material hardens on to the cool plate taking on the shape of the mold.
Our Specialty – We stock many standard injection molded parts, our prices are very competitive and our design capabilities are unlimited.
Benefits of Injection Molding
Injection molded parts are often the best choice for complex, high volume products that require tight tolerances. Our engineers will work with you to design a plastic injection molded part with the lowest tooling cost in the industry.
- Minimal finishing work needed on final product
- Quick turnaround time