PRODUCTION OF POLYURETHANE FOAM

The process is consists of five steps:
a) raw materials conditioning;
b) measuring out of raw materials;
c) mixing of raw materials;
d) trigger reaction;
e) growth verification.

The three main raw materials for the production of the flexible polyurethane foam are POLYOL, TDI, and WATER. The water is the essential element for life and it is also the reagent that allows the foam to expand and to rise.

The raw materials are accurately conditioned and the different components are carried to a variable temperature between 20°C and 25°C that is the best processing temperature.

Polluting and harmful elements such as CFC and METHYLENE CHLORIDE have been banished from the process.

Raw materials, stored in tanks, are proportioned in the mixing head where the trigger reaction takes place.

Polluting and harmful elements such as CFC and METHYLENE CHLORIDE have been banished from the process. Raw materials, stored in tanks, are proportioned in the mixing head where the trigger reaction takes place. The foam goes from the mixing head to a tank or to a conveyor.

The reaction (polymerisation reaction) takes place in 1/3 minutes; during this time the foam block reaches the fixed dimensions. When the foam block gets out of the tunnel it is cut into variable length boards that are laid on the maturation system.

During the 72 hours after the production process, the polyurethane reaction ends and the boards are stored in warehouses.

After that, the product can follow two different paths: it can be cut into 2, 3, 4 mt blocks and be sold as a rough block or it can be brought in the cutting division of the company.

VARIABLE PRESSURE FOAMING PROCESS

Thanks to VPF (Variable Pressure Foaming) System, an innovative foaming method, we have been able to improve our production processes.

As a matter of fact Pelma is the only company in Italy that employs this exclusive technology. In this way the quality has improved continuously and the specifications of the product can be constantly tested during the process.
Nowadays, apart from our Italian factory, there are six other factories: four of them are located in the USA and two in Europe.


Our technology is mainly based on vacuum and pressure foaming process variables. This prevents from using external uncontrollable agents (such as CFC/HCFC, Methylene Chloride, CO2...). The chambers of VPF system can be considered as closed reactors where the pressure can be constantly fixed and controlled.


VPF gives the possibility to obtain a wider range of products, creating new foams with improved properties.

Among the different qualities of VPF method, the high environmental compatibility is to be mentioned. The tunnel in which this process takes place is completely closed and the gases generated during the foaming reaction are collected inside the plant and are cleaned by active coal filters before being released in the atmosphere.

Our production respects environment, and our research has made polyurethane foams a supple material, widely used in everyday situations and in a wide range of applications.

For this reason, and thanks to the constant development over the past 50 years, polyurethane foams have proved to be a reliable product, safe and totally compatible with the environment.

By courtesy of
Research & Development
of PELMA S.p.a.