Where Small Spheres and Heat Create a Big Effect

Author: Anja Wieder, Manager Marketing Communication, Leister AG, Switzerland
Copyright images and video: FILL Gesellschaft mbH

When Heat Becomes Visible

A visit to the industrial plant is unforgettable: From the outside, it appears calm and closed in bright metal, but behind protective glass, a different picture unfolds – infrared emitters glow deep red, no clouds of steam, no hissing, just concentrated heat, precisely where it is needed. Here, inside, plastic beads are transformed step by step into a material that protects, insulates and shapes our everyday lives.

From Granules to Everyday Hero

In the particle foam industry, it all starts with small, hard plastic beads – mostly made of EPS (expanded polystyrene) or EPP (expanded polypropylene).  They only reach their full potential through targeted pre-foaming. The beads expand, becoming light, stable, and heat-insulating. They are then welded together in molds to form finished components. This is how products are created that we use every day, often without consciously noticing them. 

The foamed beads are used to create, among other things, protective packaging for electronics and household appliances, helmet inner shells for bicycle and protective helmets, vehicle parts such as seat cores or energy absorbers, and insulation panels for buildings. This material is also used for thermal boxes for food or medicine, child car seats, floats or lightweight components for industry and logistics. Familiar images from everyday life include white polystyrene packaging, insulation material on construction sites, or cooler boxes – lightweight, stable, and reliable. 

Precise Heat Instead of Steam

For more than ten years, the Austrian company Fill Mechanical Engineering and Leister have been jointly developing energy-efficient solutions for heating thermoplastic materials. One focus is on steam-free pre- and post-foaming in the particle foam industry. 

In Fill pre-foaming systems, such as the IR-EXPANDER 340 and IR-EXPANDER 1400, Leister's infrared technology ensures that the plastic beads expand evenly and in a controlled manner. The heat acts directly on the material – efficiently, reproducibly and visibly. 

Proven in Various Industries

The collaboration extends beyond particle foam processing. Leister infrared emitters are also used in HDF (Hot Drape Forming) plants for the aerospace industry and in welding systems for EPP components. 
This diversity shows how flexibly the technology can be adapted to different requirements – from delicate composite components to large-volume foam products. 

A Partnership that Lasts

As a special-purpose machine manufacturer, Fill relies on competent and reliable suppliers who implement customer requirements quickly and precisely. 

“For us, it is crucial that technological solutions function reliably and can be flexibly integrated into our machines. The long-standing collaboration with Leister is based on mutual trust and technical expertise”, Heinz Hohensinner, Project Planning and Sales at Fill.

The continuous development of Leister infrared technology ensures that both companies benefit from each other in the long term. Each new plant is built on trust in the technical expertise of the other party.  

When Efficiency quietly Convinces

Ultimately, it's not about spectacular effects, but about stable processes. To create plastic spheres that have exactly the desired structure. Products that protect, insulate, and provide security. And infrared technology, which shows its strength where heat is used precisely. 

Would you like to learn how infrared technology can make your particle foam processing processes more efficient? Discover the possibilities of Leister's infrared solutions.