There are different kinds of plastic types. PE pipes are more expensive and it is mostly more difficult to get them but they are much more flexible than PVC pipes and can be carried as roller.

Contents 1 PE pipes 1.1 PE pipe diameters 1.2 Pressure ratings of polyethylene pipes (PE) at 20°C (68F)[1] 2 PVC pipes 2.1 Where to use 2.2 Tips for dealing with PVC pipes 2.2.1 Temperature 2.2.2 Cuting 2.2.3 Forming

PE pipes

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They higher density also means a higher price for the PE pipes. As fare as possible don't fuse LDPE, MDPE or HDPE pipes with HPPE pipes, because the have a different plastic structure with different fusing and pressure characteristics. (See Pipe Fusing (PE)). HPPE pipes are usally used for pipes with a greater diameter (90mm and more).

PE pipe diameters

HPPE pipes are usally used for pipes with a greater diameter (90mm and more), LDPE pipes for smaller diameters. MDPE and HDPE pipes are availible for the full diameter spectrum (20-1000mm).

The diameter of PE pipes is specified by the outside diameter (OD). These makes it a little more difficult to calculate water schemes by hand or by software. One data the pipe producers normally mensure is the standard dimensional ratio (SDR). The SDR is the ratio between wall thickness and outside diameter of the pipe:

<math>Standard~Dimensional~Ratio~(SDR)} =\dfrac{Outside~Diameter~(OD)}{Wall~Tickness~of~the~Pipe}</math>

Pressure ratings of polyethylene pipes (PE) at 20°C (68F)^[1]

	Outside Diameter (mm)	Standard Dimensional Ration (SDR)	Pressure (bar)
MDPE	20 - 63	11	12
	90 - 315	11	10
	90 - 1000	17.6	6
HPPE	90 - 500	11	16
	90 - 500	17.6	10
	160 - 1000	26	6

PVC pipes

Where to use

Polyvinyl Chloride (PVC) pipes are much little flexible than PE pipes. Therefor they are not recommended for complex water supply systems but they are ideal for the usage indoors. Usefull are PVC pipes for example for rainwater harvesting, as roof gutter or for indoor water distribution and sewerage piping systems.

Tips for dealing with PVC pipes

Temperature

Beware to use PVC pipes in freezing conditions and protect them from direct sunlight, otherwise they will become brittle.

Cuting

You can cut PVC pipes with a simple handsaw, a power saw or a special PVC saw. It is recommended to wear glasses for eye protection.

Forming

PVC pipes can be formed by filling them with sand and heating the area to form. But this is only recommended in emergency cases if no standard bends available.

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1. ↑ Davis, J. and Lambert, R.: Engineering in Emergencies; ISBN 978-1-85339-5215