Polyethylene pipes for water supply: characteristics and

Modern construction and technological materials can significantly transform the familiar world, and many of them are for the better. One of such materials is polyethylene, which is successfully used in cold water supply and sewage systems.

We will talk about the characteristics of the material and show how the installation of polyethylene pipes for plumbing with their own hands.

PND-pipes for plumbing

Specifications

The main properties and features of products from PND are caused by qualities of initial material - polyethylene.

This is a synthetic polymer plastic, which, like many other members of this group, has a number of unique properties:

• moisture resistance;
• no corrosion;
• inertness to most acids and alkalis;
• elasticity;
• ability to take almost any form as a result of casting or pressing.

However, we are interested in the specific features of this material in relation to its use as a transport vessel for water.

Technical characteristics of polyethylene pipes for water supply are as follows:

• The operating temperature of PE pipes ranges from 0 to 40? С. In this case, a short-term increase in temperature up to 80? С and a decrease below zero are allowed;
• Working pressure ranges from 6 to 16 atmospheres. Determined by the SDR index, which is equal to the ratio of the diameter of the pipe to the thickness of its wall, that is, the smaller this indicator, the greater the pressure the product can withstand;
• Wall thickness can vary from 2 to 60 mm. As a rule, thick walls are characteristic of large diameters;
• The diameter of the pipe is in the range from 10 to 1200 mm. This is the outer diameter, which is indicated in the marking along with the wall thickness. If we subtract the double wall thickness from the specified diameter, we get the inner diameter and we can determine Du;
• The density of polyethylene is approximately equal to 950 kg / m ?, which is lower than the density of water. This means that the specific weight of a meter of a product is relatively small, with very large diameters it can reach 200 kg;
• The material is plastic and can withstand water freezing inside the pipe without destroying it.. It also smoothes water hammer;
• The roughness of the inner surface does not exceed 0.1, which allows the use of products less than one diameter step than steel pipes for similar needs.

Note! Even this short list of characteristics is enough to see the obvious advantages of PE over steel, cast iron and other metals. To this can be added the fact that the price of production of pipes from HDPE is significantly lower, and the costs of transportation and installation are also much reduced.

And even with this good "plastic" news is not limited to: other representatives of synthetic plastics - PVC pipes for water mains - are successfully used for cold-water systems.

Installation

We will consider one of several possible methods of installation - welding using electrofusion couplings. To do this, you need special shaped parts for polyethylene pipes for water supply, which are docking sleeves with an integrated heating element and terminals for contact with the power source.

In addition, the work will require a special welding transformer and a positioner that allows you to quickly and conveniently fix parts in the installation position. All these tools can be rented.

Also not unnecessary will be auxiliary tools - a shaver for stripping the top layer of the welded end and a pipe cutter for smooth and fast trimming of pieces.

Further instructions are very simple:

1. The end to be docked should be cut to the size of the pipe cutter strictly under 90?;

1. Then, using a shaver or other tool, remove the top layer of plastic along with dirt and bloom to the width of the insert in the pipe sleeve;

1. Wipe the cleaned area at the end of the part and the inside of the coupling with acetone or universal solvent;

1. Measure with a ruler half the length of the coupling and make a marker mark on the pipe, along which we will insert it into the connection;

1. We perform the same actions with the second end to be joined, then we insert both ends into the clutch by the mark and fix them in the positioner;

1. Turn on the welding machine, connect the wires to the terminals, read the bar code from the body of the fitting and press the start button;

1. We are waiting for the connection to cool and turn off the contacts. You can print a report on the work done (if the device allows).

Note! At observance of all the rules of welding, the joint is no different from a single piece of pipe and is able to withstand pressure up to 16 atmospheres.

Conclusion

Low-pressure polyethylene pipes are one of the highest quality materials for mounting cold water conveying systems. Plastic water supply has a lot of beneficial differences from steel counterparts. The video in this article demonstrates pipe installation.