Difference between PU casting and Injection molding

Difference between PU casting and Injection molding.

For one to be able to be able to choose the best manufacturing selection to go for he or she should start by highlighting the differences between existing methods of manufacturing. In this article, we’ll discuss the key differences that exist between injection molding and urethane casting in order to make the process of project selection easy for anyone finding it difficult to make a decision on what to go for.

The processes we are going to look at are almost similar processes that may give varying results depending on your preferences and final expectations.

Let’s get started by looking at existing differences between injection molding and casting.


As we have seen above, these are processes that are almost similar. They can be differentiated by going deep into details to find out how they function. For instance, while casting involves filling mold cavities by directly pouring the material, injection molding involves using pressure to cavities in molds using a specialized machine.

The similarity that exists between these two processes is the fact that the material that is filled in cavities is allowed to cool then ejected from cast or mold.

The other difference between these two processes lies in the type of materials used. Injection molding makes use of molds created from hardened steel or soft metals such as aluminum. Mold Materials used in casting are derived from silicone rubber.

Other than this difference in materials used, there is also a difference in terms of materials that are suitable for each process. While suitable materials for casting are those that have close qualities to materials used in injection molding, the latter uses materials such as ABS, PVC and many more others.

The size of cavities in every mold in injection molding is usually larger which results to production of high quantities. In casting, you’ll notice that the quantity produced at once is smaller.

Another important difference between these two processes lies in tooling process. While casting uses 3D modeling, injection molding uses  CNC machining type of grinding., edm to make the tools.

In terms of costs, injection molding tends to be costly compared to casting. Investing in injection molds is usually a good thing because it will definitely pay itself in the long run. It can cost you something close to $2000 producing casts but it may cost you tens of thousands to produce molds using injection molding process.

Now that you have this important information, you will now find it easy going for the process that suits you or what you think is better. if you wish to get more insight in what factors determine mold costs. read this article:

What factors determine injection molding costs?