Cost of Plastic Injection Mold in China
What is plastic injection molding
Plastic we all know, but plastic injection mold is unlikely to sound familiar to too many people. Yet, this is the most common process used to fabricate plastic parts. Especially for plastic parts that must have a thin wall. For injection molding of plastic, one needs an injection molding machine, and a mold, apart from the raw material. The process seems simple enough: first the plastic is melted in the injection molding machine. The molten plastic then gets injected into a mold. The plastic cools in the mold and reaches its final stage. The biggest benefit of injection molding of plastic is that it can make parts in large numbers with limited scrap. Also, injection molding is extremely repeatable which makes it an ideal process to ensure the consistency of the brand and the reliability of the parts. But the flipside is that it involves an expensive and lengthy tooling process.
Mold or die in the plastic injection molding process is that part without which plastic fabrication would be impossible. Molds are not cheap. Manufacturing a mold is an expensive process. Aluminum, hardened or pre-hardened steel or an alloy of beryllium and copper are the ingredients made to make molds for plastic injection molding. Molds have two parts: the injector mold and the ejector mold. Producing a mold involves designing and prototyping. The initial designing normally happens on a 3D printer. The prototype gets produced using some material like ABS plastic, which is not quite as expensive as the final material. Anything between 300-1000 prototypes may be needed for testing before finalization. Before using the mold for mass production, it is necessary to refine all the details in an injection mold manufacturing plant.
Why such a lengthy process is necessary
The value of injection molding of plastic is in its capacity for mass production. That is why molds are made of hard materials as mentioned. Naturally, once it is made, it is not easy to make changes. That is why the initial preparation process of the tool involves so many stages and so much time. That also influences the cost of plastic injection molding.
Size as a price driver
You need to have a prototype ready even to receive quotes for plastic injection molding. The next important thing is the cavity. A mold with two cavities, for example, means it will yield two pieces at a time. If you want to get more pieces from the mold at a time, you will need more cavities. The number of cavities decides the size of the mold. The size of the mold will obviously influence its price.
The mold and part materials
You already know the types of materials that are used to make molds. But aluminum and steel can vary in quality. If you ask blindly, you might get a price range of anything between US$2000 to 10,000 for the same mold. The part material will obviously be plastic, but there are many different types of plastic as well. So you see, you need to do some research.
A final tip
China is a hub of plastic injection molding. You could well think of getting quotations from there. Go for a company that guides you in deciding the mold and part materials as per your requirements. Anyone quoting only the most expensive is suspect.