How Do You Mold Large Plastic Parts?: The Structural Foam Molding Process and Advantages

Large plastic parts and products are needed in many industries, including construction, consumer goods material handling, and more. Unfortunately, finding the right manufacturing processes to create large plastic parts can be difficult. Many times, creating these parts is expensive, and time-consuming, and you run the risk of having issues with deformities. So, how do you mold large plastic parts and products? One of the best ways is through structural foam molding. Continue on to learn more about the process and its advantages.

The Structural Foam Molding Process

The Manufacturing Process

The structural foam molding process begins with mixing a melted polymer with nitrogen gas and/or a chemical blowing agent. This mixture is then injected into the structural foam mold under low pressure. The polymer mix will touch the walls of the mold and cool, forming a product with a solid exterior and honeycomb interior. The result is a large, complex product with a durable exterior layer and a less dense inner layer, reducing its weight compared to its injection molded counterparts.

Plastics Used in the Structural Foam Molding Process

Polyethylene is the most common plastic used in the structural foam molding process. This polymer is resistant to chemicals and water, is recyclable, has a high strength-to-weight ratio, low moisture absorption, high impact strength, and is durable. However, polyethylene does have poor weather resistance, is flammable, and can be sensitive to stress cracking. Polyethylene is used to create chemical containers, pipe systems, gardening equipment, and more.

Benefits of Structural Foam Molding

Create Large Parts Easily

The low-pressure process requires less clamping force which allows you to create tooling and molds from more cost-effective materials, such as aluminum. This low-pressure process also leads to less damage, reducing the cost and time spent on rerunning projects.

Design Flexibility and Reduced Risk of Warpage

Again, the low-pressure process puts less stress on the product, so it doesn’t experience as much damage as parts that are produced through straight injection molding. This reduced risk of warpage allows you to create more complex molds that maintain the desired shape of the finished product.

Efficiency

Multiple structural foam molds can be run at the same time. The low-pressure process allows molds to run simultaneously without putting stress on the machines and the models, saving you time and money in your manufacturing process.

Desirable Physical Properties

Structural foam molded products have many desirable properties, including a high strength-to-weight ratio, good thermal stability, durability, chemical resistance, and more.

Structural Foam Molding Applications

Numerous industries use structural foam molding to create their products. Port Erie has been lucky enough to partner with many companies to manufacture the large tonnage plastic products they need, including HDPE trench drains, garden carts, lawn equipment, and pallets. Learn more about the products created through structural foam molding by viewing our blog.

Ready to Learn How You Mold Large Plastic Parts? Contact Port Erie Plastics

At Port Erie, we have been creating plastic products through structural foam molding and injection molding since 1953. Not only do we have the capabilities to create your products, but we take quality into account from the very start by offering in-house tooling and mold design. Plus, our team also assigns a skilled plastics engineer to each project to ensure your products are of the highest quality and designed for efficient manufacturing.

Contact our team today to learn more.