1. Extrusion
The production process for EPS boxes begins with small polystyrene beads. These beads, which appear solid, contain a blowing agent inside. This gas is essential for the subsequent stages, as it allows the material to expand when heated.
2. Expansion
Next, the beads are heated using steam. The heat causes them to swell to approximately forty times their original size, creating tiny air cells within them. It is this specific structure that makes EPS lightweight and provides its excellent insulating properties. After pre-expansion, the beads are transferred to silos for a resting period of several hours; during this time, they cool and stabilize, preparing for the final stage of the process.
3. Molding
Once ready, the expanded beads are fed into molds that match the final shape of the box. A further application of steam causes them to expand again and fuse together. After a cooling process, the final container is formed.
