When to Use Single Cavity Mold or Multi Cavity Mold?

As one of the most widely used methods in plastic parts manufacturing today, injection molding can facilitate large, cost-effective production runs of the same parts. In fact, in most cases, injection molding is the most cost-effective method for producing high-volume plastic parts. Therefore, it is generally superior to other manufacturing methods, including CNC machining, polyurethane casting, and die casting.

1. Single cavity mold and multi cavity mold injection molding process

Injection molding begins with the creation of the mold itself. The mold, which will later be filled with molten plastic to create the required part, is the most complex part of the injection molding process. Fortunately, it only needs to be created once. After the mold is made, injection molding becomes a six-step process that is easy to replicate. The first step is to clamp, or push the two clamshell halves of the mold together. Next is injection, where the plastic is melted and inserted into the mold. The next step is to stay and cool down to allow the plastic to fill the mold and solidify. Finally, the mold is opened and the thimble takes out the part.

2. Choose a single cavity mold or a multi cavity mold

Single cavity mold is the cheapest option when placing injection molds. The tool will produce one mold at a time within the set cycle time. When the cost is not so high, it is suitable for small batch production. Single cavity mold is usually easier to produce, which reduces delivery time and costs. The advantages of multi cavity molds with tools to produce multiple identical parts are volume and cost. If the cycle time to run a single impression tool is 30 seconds, 120 parts will be produced per hour. If a multi cavity mould has two cavities, it will produce twice as many parts in the same time frame. Manufacturing two or more parts at a time can reduce molding costs and provide more opportunities to produce higher yields within a set time.

Generally speaking, the choice of single cavity mold or multi cavity mold depends on the time frame and requirements. When many identical parts are required within a set time frame, a multi cavity mold is usually a better choice. Multi cavity molds allow manufacturers to make more parts faster-a clear advantage of using multiple cavities at once.

3. Select a single cavity mold or a multi cavity mold when designing

It is always wise to understand your market and the needs of your products so that you can design and manufacture to minimize costs. This is especially true for injection molding. Considering the time and a lot of cost required to create a mold, it is important for the product team to conduct due diligence and select the mold type that best suits the product and market needs.