Thanks to excellent resistance to high temperature, PE-X pipes became interesting for thermo-sanitary applications many years ago, and have been established for these applications for over 35 years. Wherever hot water is used, PE-X is the solution for all classes of hot water application, including the UK Class S with a higher boiler malfunction temperature. PE-X is the only plastics material that covers the whole temperature range with excellent low temperature toughness, and is the only plastics material that can be used for gas supply systems in a temperature range of -50 ˚C to +60 ˚C in accordance with ISO 14531.
PE-X materials can be extruded for all the pipe structures now available on the market, from the all-plastic pipes to co-extruded pipes with 3 or 5 layers using EVOH or aluminium.
PE-X is certified by institutes around the world for use in contact with drinking water. Product evaluation involves a formulation review of all water contact materials, chemical extraction testing, toxicological evaluation and manufacturing facility audits.
An important factor to take in consideration in the installation of pure plastic pipe for heating applications is the permeability to oxygen. The oxygen present in the water or coming from air may create corrosion of metallic components present in the heating system. The coextrusion of PEX with a barrier layer resistant to oxygen like EVOH is the solution.
PE-X can be used to produce multilayer pipes with aluminium as well as pipes with oxygen barrier. Companies can produce pipes with EVOH in the middle (5 layers pipe) or outside (3 layers pipe), ensuring protection against oxygen permeability. This reduces potential damage deriving from the oxidation of the metal components of the boilers, which may occur if oxygen is present in the water. Thus PE-X is giving assurance of not only a long pipe life but also protection of the heating device.
Nowadays the largest sector of the PE-X market is for multilayer pipes, e.g. coextruded pipes PEX/Al/PEX. These type of pipes give the end users the advantages of a metallic pipe such as mechanical resistance and resistance to oxygen permeation, whilst excluding corrosion, weight reduction, rigidity and eliminating potential conduction of electricity.
Advantages versus metals
- Corrosion resistance
- Low weight
- No build up of deposits on the pipe bore
- Low pressure loss
- Use for re-lining a possibility
- Heat fusion welding
- Low temperature toughness
- High flexibility
- Fast and easy installation
- Lower installation cost
- Longer term stability
- High chlorine resistance
- High Scratch resistance
Contact: European PEX Association: firstname.lastname@example.org
For more information on PE-X materials see www.pex-association.net