PVC (polyvinyl chloride) PVC is currently the most used material for plastic pipes. Since PVC contains chloride, a smaller quantity of ethylene is needed to produce the material, which means that PVC is relatively cheaper to manufacture than PB and PP. PVC pipes are used for all types of pressure and gravity pipes. PVC pipes are also used as conduits for electric and telecommunications cables, for drainage pipes and for industrial process pipelines where the temperature does not exceed +45°C.
PE (polyethylene) PE pipes were previously designated PEL, PEM or PEH pipes, where the last letter refers to the density of the material: L = Low, M = Medium, H =High. However, this method of classification does not provide any information on the long-term strength of the polyethylene material. Therefore, in the on-going European standardisation work (CEN), a new method of classification has been adopted that is based on the strength of the material: "Minimum Required Strength", abbreviated to MRS. This indicates the stress the pipe material can endure without breakage over a period of at least 50 years. PE 100 piping, according to the previous classification system is equivalent, with respect to density, to PEH pipes while PE 80 pipes covers both PEM and PEH pipes according to the earlier designations. PEL pipes in accordance with the old classification system is now classed as PE 40 pipes. PE pipes have the same application area as that given für PVC pipes. Furthermore, PE pipes are also used für gas pipes and submarine pipes.
PP (polypropylene) PP pipes are available as homopolymers or copolymers PP-PE (copolymer: a small addition of ethylene during polymeisation has been made to make the material tougher). PP pipes are used as indoor wastewater pipes, buried wastewater pipes, tap water pipes and for industrial process pipelines.