Polyurethane liners
Research and development of new polyurethane polymers have opened the way for new production solutions. The products lined with polyurethane have a high potential for applicability and can indeed be used in the steel industry as well as in the textiles, graphics or paper, wood and plastic, oil, agro-food, an even the packaging ones.
Compared with rubber, polyurethane products offer higher performance from the physical and mechanical point of view: they allow, in fact, a significant increase in operating times and a consequent improvement in productivity.
Polyurethane is an elastomer with a high coefficient of thermal expansion: for this reason it can not achieve precision parameters that are similar to those of the metals.
Polyurethanes combine the advantages of natural and synthetic rubbers (elasticity, high elongation under load), to those of the plastic materials (hardness, high load capacity) for this reason they grant technical applications otherwise not achievable.
The fundamental peculiarity of polyurethane products is their resistance to abrasion, tearing, shear, compression, chemicals, ozone and finally to the low elastic hysteresis.
Our manufacturing process:
Sifra International undergoes a rigorous manufacturing process for the production of polyurethane and all the following steps are strictly adhered to:
- Sandblasting this process has the purpose to clean and roughen the area to be lined, so as to favour the adhesion between adhesive and metal.
- Degreasing this process has the objective of eliminating impurities or traces of cutting oil or grease from the workpiece to be lined.
- Pickling this process has the function of eliminating any residues of dust and dirt after sandblasting from the material to be lined (rollers, wheels, etc.).
- Cementing thanks to specific primers we improved, this process has the function of ensuring the adhesion between polyurethane / metal by a thin and homogeneous layer of glue that is spread on the roller.
- Preparation and assembly of the mould he assembly of the mould is a process that allows you to create the cavity, depending on the size and fits listed in the technical annex to the contract, where the process of casting the mixture of polyurethane will be performed.
Finally, we continue with the casting process, the polymerization, the subsequent curing of the material, turning or end grinding according to the requests of the drawing, passing then, where required, to the assembly of bearings and supports, and finally to packaging and to storage.
Sifra International polyurethanes are obtained by casting thus offering a superior quality in the context of ether and ester-based polymers. Sifra International is also able to offer coverings made with rotational method the technical term for the so-called “ribbon flow”.
