Pre-expanders are automatic machines for expanding polystyrene beads (EPS).

Our pre-expanders are fully automatic machines for expanding EPS. Pre-expanders guarantee superior performance over time and maximum quality in the EPS processing phase in terms of:
Efficiency: constant quality and repetitiveness of the material with reduced cycle times.
Minimum residual humidity in the expanded material.
Broad range of densities available.
Pre-expanders make use of an innovative expansion chamber designed to ensure the uniform distribution of steam. The fluidized bed is designed to guarantee uniform diffusion of the air inside it, in order to dry the material quickly and speed up the discharging phase.
This discharging system ensures the smooth passage of the material onto the pneumatic conveyor without modifying the specific characteristics of the individual beads.
A truly wide range of options are available to accommodate various requirements, including:

  • EPS colouring device,
  • second expansion unit,
  • pentane gas recovery system,
  • heating of the fluidized bed.

These machines stand out for their manufacturing quality and attention to detail:
Robust and compact structure, made to ensure maximum stability, strength and operating safety. The machine is also designed to facilitate safe and secure access to all its components when maintenance is required.
High-quality, easy-to-find components guarantee superior performance over time and advanced control systems for the safety of the end user.
User-friendly interface to guarantee minimal set-up times with the possibility of automatically changing the parameters according to default values. A broad range of configurations makes it possible to set up machine parameters in order to optimise production in any use conditions.
Integrated remote assistance software in all the machines for immediate management to resume operations thanks to dedicated highly qualified personnel.


These machines expand polystyrene by means of continuous cycle operations and they allow to achieve bead densities between 40g/l and 15g/l in the first expansion.
These machines can be integrated with second expansion unit in order to achieve lower densities up to 10g/l.


EPS beads expansion is performed in batches in order to obtain maximum uniformity of material density.
Process repeatability is ensured thanks to the fully automatic density control system.
Batch pre-expanders allow to achieve, in first expansion, densities between 100g/l and 12g/l.
These machines can be also integrated with a second expansion unit in order to achieve lower densities up to 8g/l.

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