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Casting & Molding Products In Plastic Injection Molding

Die casting, as is commonly understood, is a process for producing engineered metal parts. The process entails forcing molten metal under high pressure into steel molds or dies that are reusable. These dies can be designed to produce complex shapes with a remarkable accuracy as well as repeatability.

A plastic die casting process is favored by many industries today because of some its advantages over plastic molding. It can be said that die casting produces sturdy and more durable parts with closer tolerances. Furthermore, die cast parts have greater resistance to extreme temperature and possess superior electrical properties.

The die casting process constitutes injecting molten plastic under high pressure into a die or a mold. Die casting machines are typically rated in clamping tons, indicating the quantum of pressure they are capable of exerting on the die.

There are two types of die casting machines and their only basic difference is the methods used to inject molten plastic into a die one has a hot chamber and the other a cold chamber. A complete die casting cycle can vary from less than one second to three minutes depending on the size of the desired product. This makes die casting the fastest technique for producing precise plastic or non-ferrous metal parts.

It needs to be stated that die casting is an efficient, economical process offering a broader range of shapes and components than any other manufacturing technique. The key benefits of die casting can be summarized as: high speed production capability /complex shapes within close tolerance limits/ guaranteed dimensional accuracy and stability/ finished products are heat resistant and sturdier than plastic injection moldings of similar dimensions / multiple finishing techniques/ end products can be easily plated or finished.

As regards the question of die casting or plastic molding, it can be said that die casting produces sturdier, more durable parts with closer tolerances. The construction of die casting dies is almost identical to that of molds for injection molding. Die cast parts have greater resistance to extreme temperature and possess superior electrical properties. Compared with plastic injection moldings, die castings better help prevent radio frequency and electromagnetic emissions. For chrome plating, die castings are much more compatible than plastics.

There is no denying that the art and science of transforming plastic resins into useful products or components through the process of injection molding, has had a tremendous impact on commercial and industrial spheres. Injection molds can be quite expensive but if the desired part quantity is large, the mold cost will become cost-effective in the long run. Some molds are of course made with multiple cavities; these multi-cavity mold leads to increased production efficiency and the cost per part are considerably minimized.

Although an injection molding machine is a complex piece of equipment, it consists of two basic elements, the injection unit and the clamping unit. Historically speaking, injection molding process was originally designed only based on metal die casting designs. Injection molding has gained a lot of popularity in a very short span of time due to its own peculiar merits. Injection molding offers many advantages including minimal losses from scrap as scrap pieces can be melted and recycled. Injection molding has minimal finishing requirements. Injection molding process fundamentally differs from metal die casting - molten metals can simply be poured whereas plastic resins must be injected with force.