Sep 09/20

What Materials Can Be Used in Injection vs. Compression Molding?

compression molding vs injection moldingLeading manufacturers have long considered, which process is superior for increasing productivity, making reliable parts in less time, and with lower overheads.

We’re talking about compression molding vs injection molding.

There are advantages and disadvantages to both processes.

So, continue reading to find out more…

What’s Injection Molding?

This is one of the most popular means of manufacturing molded rubber products. Injection molding involves injecting a hot liquid compound into a closed cavity where it is vulcanized or hardened by treating it with sulfur at a high temperature. So. the result is a stable rubber that needs little aftercare.

As a result, often used to produce high volume automotive parts and components, gaskets, balls, and other mass volume rubber items.

What’s Compression Molding?

Preheated material, such as thermoset resins are inserted within a heated mold cavity, which then closes or gets forced down by pressure. The resins are then distributed through the mold and kept at a high preset temperature cured under pressure.

The result is a high-quality, stiff, and durable rubber used in a variety of industries, including the automotive industry. Compression molding is often used to produce high volume gaskets, seals, and grommets. Common materials used include EPDM synthetic rubber, silicone, and natural rubber.

The Pros and Cons of Injection Molding

Let’s start with the pros:

  • Shorter and higher production time than compression molding
  • Less labor-intensive
  • No ‘flash’ so less waste

Now for the cons:

  • Higher costs of tools
  • Expensive materials

Below, we’ll now look at the advantages and drawbacks of compression molding:

The Pros and Cons of Compression Molding

Again, we’ll start with the perks:

  • Some manufacturers say compression molding machines are easier to maintain
  • Lower costs
  • High Production volume capacity
  • Seamless design

Now, for the drawbacks:

  • Better used only to create simple parts
  • ‘Flash’ manually trimmed, slows the process down with higher labor costs
  • Slower process than injection molding

So, on balance, which should you go for?

Compression Molding vs Injection Molding: Which to Choose?

Unfortunately, there’s no right answer here. Therefore, it really depends upon the types of products you need to create. It’s possible to custom create colored rubber to suit your manufacturing needs using both processes.

However, compression molding is slower than injection molding, whereas injection molding is fully automated. Compression molding, primarily used to create larger rubber products, while injection molding best suits smaller rubber parts. Compression molding is also successful when manufacturing parts that vary in thickness from 1.3mm to 2.5cm.

Ready to Find out More?

Hopefully, you’re well on your way to understanding the compression molding vs injection molding debate. Deciding between the two, however, can be tough. It’s best to choose a manufacturer who fully understands which process best suits your needs.

That’s why our team at Mayco International prides itself on being able to navigate what’s best for your manufacturing business. In short, feel free to get in touch with us today to see what we can do.