Sewage pipes, from cast iron to multi-layer polyolefin silent grade

Nowadays, it is important in buildings that the sewage systems be as silent as possible, especially in cases such as discharge of kitchen appliances. For many years, cast iron pipes and fittings have served successfully, due to their large density which provides sufficient sound attenuation. New building designs, however, do not tolerate heavy cast iron pipes and
prefer plastic replacements. A practical approach tried earlier to overcome the weakness of plastics in sound attenuation was to increase pipe’s thickness, which increased pipe weight
and installation difficulties. Introducing mineral fillers in plastic pipes was the next approach employed which resulted in thinner pipes with reasonable level of sound transmission. However, this was achieved at the cost of mechanical properties, especially impact strength. More recently, multi-layer pipe technology was developed to improve mechanical properties of pipes while maintaining the sound attenuation characteristics of filled PP. Although this technology has made a great success; impact strength of manufactured pipes is still unsatisfactory because of the inherent properties of filled PP.

ParsaNano silent formulations are materials of choice for pipe manufacturers who look for the benefits of low weight and easy to work with plastic pipes along with the sound attenuation and excellent mechanical properties. Figures 1 and 2 illustrate the advantages of ParsaNano silent grades in comparison with traditional cast iron and neat PP pipes.