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CHAPTER 9. Piping and fittings
One clear exception to some of these rules is the use of HDPE, which, in my opinion, is the material of choice.
Logistics Material logistics are vital. There are few things that can delay or cause a project to fail more than receiving a delivery of materials which is inadequate. In the case of pipes, this can be key as they incur considerable transport costs.
Quality There are materials which are, for all intents and purposes, useless. In many places, the person who supplies the materials is not a professional, and may often buy them as if they were plastic urinals or vitamins for camels. To improve the profit margin this person may buy much cheaper materials without understanding the consequences, and you may end up with faulty parts or second hand materials. It becomes very difficult to negotiate a refund if the consequences for the supplier means bankruptcy. Organise material inspections before making any payment, and ask for samples (i.e. pipe sections) of the material quality you´ve asked for. Inspect the material before it leaves for its destination to avoid having to cover additional transport costs for refunds.
9. 2 PIPING Piping is the fundamental component of the project. Here only PVC, HDPE (highdensity polyethylene) and GI (galvanized iron) are dealt with. Other pipe such as ductile casting, asbestos, and cement, are not mentioned here as they are generally not appropriate in these kinds of contexts.
PVC This is the most popular pipe due to its low cost, ease of installation and universal availability. It´s produced in almost all diameters. However, it is considered highly toxic due to the releasing of dioxins and heavy metals. Various ecological organisations such as Greenpeace have launched campaigns to replace PVC with other products. Pros: • • •
Low cost, often being the cheapest pipe available. Universal availability. Inert. Does not react with chlorine or with most compound chemicals. Does not corrode.
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