Polypropylene is a material which is effective and durable, has a high heat resistance, is lightweight, easy to install and is also frost resistant. There are three different types of polypropylene. The P-H type of polypropylene has good mechanical properties and has a very high chemical resistance. The PP-R type of material has a high resistance to the internal pressure and it’s very much suitable for the domestic pressure water supply systems and also for both hot and cold water services. PP-B kind of material is also used for the buried sewage and waste water drainage and it also has good impact strength at the low temperatures and also has an excellent chemical resistance. The PR-B type of material is also suited for the buried sewage and waste water drainage and it has good impact strength.
High density polyethylene has been used for a long time for the purpose of drinking water pipes. This is such a material which is suitable both for the potable water services and also for the waste water services. The properties of such a material includes the resistance from the corrosion, durability good flow characteristics, is light weight and flexible, has a good bending radius, is inexpensive and requires very less number of fittings.
Another very useful materiel is the Cross Linked Polyethylene (PEX). It is a tube which is made from the cross-linked and high density polyethylene polymer which may result in a stronger material than polyethylene. This material is most durable under the extreme temperature and chemical attack. In addition to this, it has a greater resistance to the cold temperatures and on the impact of cracking and brittleness. In addition to this, it can also be used for the hot water supply and for hydronic heating systems and also for the potable water supplies. In addition to this, the material is also flexible and has an ease of installation. Though, this material isn’t recommended for outdoors above the ground. Though, it can withstand some UV exposure, this shouldn’t increase more than the optimum value.