The production process of Expanded Polystyrene is separated into three stages:

1. Prefoam: The raw material (in grains of diameter 0,4-2,0mm) is heated in special machines that are called preexpanders with the use of steam in temperatures from 80 until 100oC and it expands. With the expansion, the density of the raw material falls from approximately 600kg/m3 to 10-80kg/m3 depending on the final use for which it is intended. The microscopic grains of the raw material are expanded up to 50 times in volume. These grains are constituted of small closed cells that contain air.

2. Intermediate storage for stabilisation: Expanded EPS beads are stored in ventilated silos that facilitate the escape of pentane from their interior structure and its replacement by air. In this stage from the beads is also removed any humidity they might contain.

3. Final Expansion and Moulding: The stabilised beads of Expanded Polystyrene are transported in moulding machines like the block moulding or the shape moulding machines, where with the use of steam, the preexpanded beads, are expanded more and connect to the neighbouring ones taking in this way the form of the mould. In the block moulding machines, the final product is a large volume of EPS, which afterwards is cut in boards for thermal insulation and in the shape moulding machines the final products’ shape depends on the cavity of each mould.

The production process that was mentioned before, leads to products of Expanded Polystyrene, with excellent properties that can fulfil every need for Packaging, Construction, Insulation and Decoration.