Polypropylene pipes are mounted by diffuse welding. In the process of using fittings. These elements allow the assembly of water pipes of any configurations. On sale you can find various types of fittings for polypropylene pipes, differing from each other in their technical characteristics. They also differ in areas of application.

Specifications

The dimensions of the fittings are determined based on the diameter of the polypropylene pipe. This is another difference between them. On sale the most common pipes with a diameter of 20 mm. Smaller diameters are rare, as the products are distinguished by thick walls.

Fittings design features are:

• The use of a special thread profile in fittings, which completely eliminates spontaneous unscrewing during vibrations and water hammer in the system, allows to withstand large unilateral axial loads and jerks;
• the use of a special rubber o-ring ensures reliable sealing of the pipe, even when it is bent. At the same time, ease of installation is maintained, and spontaneous loss of the sealing ring from the fitting during assembly and disassembly is completely eliminated;
• the use of a flexible ring grip, made in the form of a “collet”, allows you to completely cover the pipe around the entire perimeter, as well as reliably hold the rubber o-ring in place.

Types of fittings

Fittings for polypropylene pipes differ from each other by the specifics of use, shape. Many factors play a role here: the characteristics of the compound, its angle. In the photo you can see the difference between the types of these products. Let us consider in more detail each of the varieties of fittings.

Couplings

The simplest design: an element whose internal size should fit the external size of the pipeline. They are used to connect two pipelines;

Adapters

They have an important difference from the first type. In particular, the ends of the structure have different internal diameters. With their help, you can connect products with thread. To do this, they must have an external or internal thread;

Corners

They are necessary for connecting the elements if bending is supposed in the pipeline construction. It is possible to bend polypropylene products through heat treatment. However, in this case, the connection is weak, since the walls of the structure are thinned, the throughput is reduced. The corner already has a shape, the angle of which corresponds to a standard rotation. It is worth noting that before inserting a part into a corner, it must be warmed up with a soldering iron. In stores you can find corners with various parameters. Usually this is an angle of 90 and 45 degrees. They also vary in size, because the diameters of the pipeline vary. Threaded products are available. Often they are used when installing mixers;

Contours

Required if the pipeline must be laid through any obstacles, and you cannot make an unnecessarily large gap. The installation pipeline is rarely bent, since it loses its consumer qualities in the field of bending. It is better to purchase a contour, which is a typical design with a bend.

Benefits:

• high corrosion resistance to aggressive substances in the soil and the transported liquid during the entire period of operation;
• low specific gravity (three times less than steel);
• high mechanical strength (tensile strength from 350 to 800%) and elasticity (polyethylene is able to stretch without losing its qualities up to 7%), which makes them indispensable in seismically active areas and in places where soil movement or subsidence of the house is possible;
• increased throughput (with the same diameter, 20-30% higher than that of steel pipes) since polymer pipes do not “overgrow” the internal passage of the pipe with oxidation products;
• the lowest complexity of installation;
• durability – the service life of steel underground pipelines is not more than 25 years, while the guaranteed life of polyethylene pipelines is 50 years;
• modern polyethylene pipes and fittings are environmentally friendly, toxicologically and bacteriologically safe.