How is Foam Manufactured?

To fully understand the manufacturing process of foam, or EPE (expanded polyethylene) foam, it’s important to first understand what we mean by EPE foam.

EPE foam is a closed-cell foam, which means its structure consists of bubble-like, gas-filled cells that remain intact, even under high pressure or constant impact.

This closed-cell structure makes EPE foam perfect for a variety of uses, including packaging, sports shoe components, cosmetics and beauty products, floatation devices, medical equipment, and many other products that require a lightweight, semi-rigid, water-resistant, and resilient foam material.

EPE Foam Manufacturing Process

Foam or EPE foam is manufactured in three key stages, which include:

1. The raw material stage

EPE begins life as Polyethylene (PE), one of the most commonly used plastics today. To get slightly scientific, Polyethylene is a mixture of similar polymers (a substance or material consisting of large molecules and repeating subunits) of ethylene ( a flammable, hydrocarbon gas).

The polyethylene in its raw state is first heated until ‘foaming’, in a contained unit, to produce a molten material. This molten material is then taken through another process, where it is cooled with the addition of water, with the resultant material then being cut into beads or pellets.

2. The extrusion stage

The extrusion process in the manufacture of EPE foam, is done by heating the beads or pellets which resulted from the raw material stage, then using high pressure to force the heated beads into the specific moulds, in preparation for forming, the final stage in the manufacturing process.

3. The forming stage

Forming EPE foam is carried out using various techniques (depending on the product being produced), which may include:

  • CNC Routing and MachiningCNC (computed numerical control) Routing is an extremely accurate way to form EPE foam, especially in the manufacture of multiple components, such as foam inserts for electronic devices etc.
  • MouldingFoam moulding, whether auto-moulding or vacuum moulding, is a process that allows a high level of accuracy, especially in the formation of 3D shapes, used in the aerospace and defence industry, and the medical industry.
  • Splitting and SkivingSimply put, splitting and skiving is carefully cutting a large block of foam into thinner sheets, which may be used in activities such as yoga or aerobics.
  • Waterjet CuttingWaterjet cutting is another extremely accurate way to form EPE foam. This forming process is often used to cut small slots or thin slits in foam, without compromising or splitting the main body of the product being manufactured.
  • Laser EngravingIn the same way you might engrave a piece of metal, laser engraving is a method of creating a permanent text or image across the surface of the foam. Our laser engraving process also allows customers to engrave their designs onto their foam products.
  • PrintingPrinting is usually the final part of the forming process, and can be extremely difficult to achieve a satisfactory finish. Here at Polyformes however, we use a patented, 4 colour printing technique, that allows us to print colourful and intricate designs on most foam products up to 1200mm wide.