Since installation polyethylene pipes They are distinguished by enviable simplicity, and they themselves are extremely attractive in price, durability and reliability; their use is becoming increasingly widespread in comparison with other materials. They are used not only in industrial, but also in household, are ideal for use in sewerage, heating, gas and water supply systems.

For better installation of pipes, you must adhere to some recommendations that will be presented in this article.

Necessary tool

To install polyethylene pipes with your own hands, you will need the following tools:

• soldering iron;
• pipe cutting scissors;
• gas keys.

As a rule, it is equipped with a set of nozzles with different diameters.

In extreme cases, scissors can be replaced with a jigsaw. But scissors are more convenient - when cutting pipes, they produce smooth edges without nicks or burrs.

Connecting polyethylene pipes will require the use of a gas wrench.

In order for the pipe connection to be as reliable as possible, a flax sealant is used - such connections have the advantage of always remaining dry. Tools for installing polyethylene pipes can be purchased at almost any hardware store.

Often, a soldering iron with nozzles and scissors are sold as a set - you don’t have to look for them specifically.

Pipe installation

Where should you start?

Features of preparation and installation of polyethylene pipes:

• Quantity necessary materials calculated depending on the length of the route, the number of corners and differences.
• Before starting installation, you must turn off the water supply, then prepare the materials in accordance with the project, after which you can begin installation.
• If in the home heating system, the laying of polyethylene pipes should be done starting from the boiler.
• After the dimensions are determined, the scraps are soldered connection fittings And . Also, using a soldering iron, polyethylene pipes are connected.

Learning how to use a soldering iron yourself is not that difficult. Of course there are many technical nuances, which are included in the installation of polyethylene pipes - the video on our portal will help you visually visualize the described manipulations.

Welding installation technology

Installation of polyethylene pipes is as follows:

All connections should be carefully inspected for leaks. After inspection, if everything is in order, the required pressure is set on the boiler and air is bleed from the radiators.

Fittings for polyethylene pipes

If PE pipes are chosen as the material for the construction of the pipeline or polyethylene pipes are to be repaired, fittings will be required to connect them. Depending on the method of their installation, fittings for polyethylene pipes are divided into several main types depending on the installation method.

There are the following types of polyethylene pipe connections:

• welding of PE pipes;
• pipe gluing;
• threaded mechanical connection.

Types of fittings depending on the method of pipe installation:

1. Fittings for polyethylene pipes, electric welded equipped with mortgages heating elements.
   If the wire is heated using electricity to a certain temperature, the polyethylene begins to melt, resulting in the formation of a uniform, tight connection where the transition for polyethylene pipes is made from one section of pipe to another. By using modern equipment for welding polyethylene fittings, it is possible to set the voltage and time necessary for high-quality welding.
2. Compression fittings. In principle, they are practically no different from those used in the installation of plastic or copper pipes.
   The only difference is the material of manufacture. They are extremely convenient to use, since no preparation or qualification is required - the fitting is completely ready for installation on pipes.
3. Butt welding. Performed using spigots - PVC fittings without the use of an electric spiral..
   The principle of connection is to heat the ends of the pipes until the material becomes viscous, after which they are connected under pressure. If the welding technology is followed, the connection point becomes homogeneous with the pipe.
4. Reducing fittings used in pipe welding different diameters– they have a threaded connection for better installation.
   Threaded fittings are also used for connections when installing PE pipes with water distribution equipment, meters, and so on.

Based on these data, we can conclude that correctly selected fittings allow you to install polyethylene pipes for a water supply or heating system with your own hands, without exerting excessive effort and without requiring special training.

Having your own source fresh water(well or borehole) with sufficient flow rate, it is possible to install water supply from pumping station in the well directly to the house. HDPE pipes are products made from low-density polyethylene that are used for transportation cold water both for domestic needs and for drinking.

Low-density polyethylene (HDPE) or polyethylene high density(HDPE) is a material obtained by polymerizing polyethylene granules at low pressure using special equipment. The result is a lightweight elastic material similar in physical properties with plastic. The heat resistance of products made from it can reach 110°C, and permissible temperature cooling reaches - 80°C.

Low pressure polyethylene is used to produce various technical products, incl. approved for contact with food. Consequently, HDPE can be used in the production of pipes for the supply of cold water, including drinking water.

HDPE pipes acquire the same technical, operational and consumer properties as the material itself:

• resistance to reagents contained in tap water;
• light weight, facilitating transportation, installation and dismantling;
• low thermal conductivity, preventing the formation of condensation;
• possibility of installation and connection different ways(electrofusion, butt, fitting);

Note! The most important consumer properties of HDPE pipes when installing engineering systems is the ability to withstand many cycles of freezing and thawing of water. When the freezing liquid expands, the pipes do not burst due to the high elasticity of the material.

• affordable cost per linear meter is another important advantage of HDPE pipes.

Technology for laying external systems in the ground

Laying pipes underground (closed) - traditional method arrangement of cold water supply and sewerage pipelines in the private sector. When arranging drainage systems, low-pressure polyethylene pipes are also used, but with a larger diameter: they are laid under small angle towards the septic tank.

Laying polyethylene pipes in trenches

Polyethylene pipes have been used for various engineering systems since 1955. Currently, the most common areas of application of these products are:

Water supply systems.
Pressure/non-pressure sewerage networks.
Gas pipelines.
Cases for laying power cables and other communication systems.

For external pipelines, it is recommended to use underground installation, as this eliminates the need to protect the material from negative influences environment: freezing in winter and strong heating and destruction under the influence of sunlight in summer. For gas supply only underground method gaskets

For underground laying The trench method or HDD (horizontal directional drilling) method is used. Currently, the most common method is trenching.

Technology for laying polyethylene pipes

Stages of work:

• Excavation. Digging trenches and pits for wells. The width of the trench should be 30 - 40 cm greater than the outer diameter of the pipe (for diameters<630 мм и >710mm respectively).
  
• Bottom preparation. Large boulders and inclusions are removed. The bottom is leveled, compacted and filled with a “cushion” - sand, gravel or crushed stone (the largest fraction in it should not be more than 20 mm). The height of this layer is from 10 to 15 cm. If there is a threat of washing out the bottom groundwater, the bottom is strengthened with geotextiles.
  
• Distribution and preparation of pipe material along the upper edge.
  
• Welding polyethylene pipes into a braid (usually used butt welding) on the edge. By doing earthworks excavation and storage of earthen soil occurs on one side, and laying of material for welding work on the other.
  
• Laying the welded lash in the trench.
  
• Serial connection with the next strand.
  
• Check the entire system for leaks.
  

Sprinkling and final filling. For sprinkling, sand or gravel is used ( maximum size fractions up to 22 mm). For the final backfill, material removed during excavation at the first stage of work is used.

Connection methods

• The links are connected into a single string using special equipment in three main ways:
  
• Butt welding.
  
• Electric couplings with embedded heating elements. For welding work where there is not enough space (wells, small widths, chambers, etc.)
  
• Compression fittings(diameter up to 63 mm). To obtain detachable connections.
  

For routing of lashes and turns, bends, crosses, flanges and tees are used, which can be cast or welded.

To protect against possible stresses during linear expansion/compression of the system, natural compensators are used: “G”, “Z”, “U” - shaped pipe turns or “snake” laying. For cold water, expansion joints are not required. Sometimes it is impossible to securely fix it with soil or install expansion joints/snake installation (with a diameter of more than 1000 mm). With a pressure pipeline type, in this case, it is allowed to install “fixed supports” at equal distances to fix large-diameter pipes.

Trench depth and profile

The depth and profile of the trench depends on the type of pipe (its ring rigidity) and the terrain conditions where the PE system is intended to be used. The depth of placement is determined by several factors:

• Load on the surface (especially in areas running under the road surface). When crossing highways or railway tracks, special cases made of polyethylene pipes with SDR are used<17 (соотношение наружного диаметра к толщине стенки).
• Backfill material.
• Properties of local soil.
• Sprinkling material.
• Working pressure in the system.
• The material of the “cushion” and the degree of its compaction.
• Groundwater.

The minimum installation depth in the trench must be at least 1 m (a depth of 1.5 times the diameter is allowed, provided there is no intersection with a busy road). When crossing with a sewer system or other communications with toxic liquids, pipes with drinking water are laid 0.4 m higher than the latter. If this condition cannot be met, the water supply system is enclosed in a case. In this case, the distance from the ends of the case to the walls of the sewer must be at least: 5 m in clay soils, and 10 m in coarse and sandy soils.

When laying in parallel with cable and other communications, the distance is calculated so that the repair of these communications does not affect the PE pipeline.

IN last years there is a steady trend: home owners are replacing old ones iron pipes to modern ones made of polyethylene. This preference can be explained by the easy assembly process, light weight of structures, low cost, corrosion resistance, and smoother internal walls. The last two characteristics make it possible not to lose water quality over time and extend the life of the pipeline itself.

Purpose

Any non-professional can install polyethylene pipes with his own hands. The main thing is to follow the instructions from the manufacturers. When buying any pipe, look at it appearance: It must be clean and evenly colored without damaging the material. No mechanical deformations or scratches are allowed.

Polyethylene pipes are used:

• when installing a cold water supply system;
• sewerage construction;
• in drainage and drainage.

Do not use polyethylene pipes for supply hot water or in a heating system - they cannot tolerate temperatures above +40°C. In addition, it is impossible to assemble and operate such pipes in rooms where the temperature is below +5°C. In the cold, polyethylene loses its plasticity and flexibility, so the seal may be compromised.

Installation of polyethylene pipes

There are several ways to connect polyethylene parts into a single whole.

Method No. 1. Compound plastic pipes working under high pressure, is carried out by butt welding. This is the most reliable method suitable for difficult places and contact with aggressive environments. Only products produced by the same manufacturer can be welded together, since each has its own manufacturing technology. Pipes of different brands are likely to form a weak seam, which over time will lead to rupture or deformation.

Method No. 2. Installation with threaded fittings. For better tightness, use a winding made of Teflon or some other sealant. If you need to connect a plastic housing to a metal one, you should use an adapter coupling or a combination fitting.

Method number 3. Assembling polyethylene pipes with glue or cold welding. Contrary to popular belief, such a connection can be stronger than the pipeline itself.

First, make sure that the pipes being installed fit together. The end should easily enter two-thirds of the connecting cuff, and then move further with difficulty. The edges must be sanded to make them rough and wiped with methylene chloride solvent to degrease.

Glue is applied with a swab thin layer both at the end of the inserted pipe and into the cuff. The pipes are brought together all the way and turned slightly. The entire connection process should take no more than a minute. Drying time – 1 hour, in case of high humidity – 2 hours.

In addition, during installation you should follow some rules:

1. Sometimes when assembling a pipeline it is necessary to bend certain sections. A bend is considered safe if the minimum radius is equal to eight times the diameter of the pipe being bent.
2. Sometimes pipes are laid inside partitions and concreted. In this case, they will have to be isolated. When the pipes are located externally, a distance of at least 2 cm must be left between them and the wall. This will prevent condensation from causing the development of mold or mildew in the cracks.
3. The pipeline must not be allowed to sag; this disrupts its operation and can lead to depressurization. Correctly placed supports will avoid problems.

Features of installation of cross-linked polyethylene pipes

In hot water pipelines or heating systems Products made from so-called cross-linked polyethylene can be used. This is a high-density polymer subjected to electron irradiation. Under their influence, molecular chains create a single three-dimensional structure.

Unlike conventional polyethylene, this material is very resistant to extreme temperatures and pressure. In the absence of mechanical loads, it is capable of operating in the range from -120 to +120°C.

Pipes are installed using two methods:

• compression fittings;
• using press fittings for plastic pipes.

In the first case, no special tools are required for DIY assembly. All you need is plastic pruning shears and two wrenches.

Procedure:

1. A crimp nut is placed on one end of the pipe with the thread towards the free end.
2. Then put on the split ring and push the pipe onto the fitting fitting until it stops.
3. The crimp nut is tightened with a wrench.

Press fittings or press-on connections are classified as permanent and require a press tool.

During assembly:

1. A clamping sleeve is placed on the pipe.
2. Insert an expander of the appropriate diameter into the pipe to the end.
3. Smoothly close the expander handles and fix them for a couple of seconds.
4. Push the fitting in until it stops.
5. The sleeve is pressed in using a manual or hydraulic press.

You often install polyethylene pipes and know all the intricacies of their connection. Share your knowledge with our readers by leaving comments on the article.

Video

We invite you to watch a video about butt welding polyethylene pipes.