How to weld plastic pipes at home. How to properly weld polypropylene pipes and fittings How to use welding for plastic pipes

Replacement or installation water pipes from scratch is a responsible process, so the material must be selected very carefully. It must be durable, corrosion resistant, and easy to use. Today, polypropylene pipes are best suited for this purpose. Among the advantages of the material are a service life of more than 50 years, ease of installation, relative cheapness of the material and many other advantages. Installation of a new heating or water supply wiring is carried out using soldering technology, also known as welding PVC pipes. Welding polypropylene pipes do it yourself - a simple process that, after a little preparation, any owner can handle. Below, we will consider what the technology of welding polypropylene pipes is and its nuances.

The main material, plastic pipes, has its own characteristics and is classified according to a number of characteristics. The first thing that catches your eye is the color. They can be painted green, grey, white or black. Marking in black means that the composition contains special additives that prevent the destruction of the material when exposed to ultraviolet radiation and can be laid directly on the ground. The rest of the colors have no differences associated with coloring and are used indoors or under a layer of soil.

Classification of pipes by purpose:

• for cold water supply (marked with a blue stripe, maximum water temperature 45C).
• for hot water supply (marked with a red stripe, maximum temperature 85C).
• universal (marked with blue and red stripes, the temperature can reach 65 – 75 C, depending on the manufacturer).

Models for hot, cold water supply and universal type have markings that indicate additional performance indicators of the material:

1. PN10 – marking of products for cold water used at system pressure up to 1 MPa (not for residential pipelines);
2. PN16 – marking applicable to universal pipes and cold water. This material can withstand temperatures up to 65C and pressure 1.6 MPa;
3. PN20 – a material with a thickened wall that can withstand pressures up to 2 MPa and temperatures of 85C (welding heating pipes);
4. PN25 - pipes reinforced with a reinforcing layer of fiberglass or foil. Withstand pressure up to 2.5 MPa and water temperature 95C.

Necessary equipment and tools

To weld polypropylene pipes you will need a certain set of equipment, these are:

1. The welding machine itself;
2. A set of heating nozzles of various diameters;
3. Cutting device;
4. Shaver – a device that removes the reinforcing layer (necessary when working with PN25 marking);
5. A bevel remover is a device necessary for aligning the ends of the cut (necessary if plastic products cut with a hacksaw or a suitable tool that does not produce a perfectly flat cut end).

Necessary tools for welding PP

Socket welding technology - step-by-step instructions

Socket welding involves connecting a pipe and a fitting by inserting parts into each other. This kind of DIY welding of polypropylene pipes is considered the simplest; there is also a butt welding system, but the technology used there can complicate the work, especially at home. Therefore, below we have described how it goes step by step process welding of polypropylene pipes.

Pipe cutting

Cut the material with a tool designed for this purpose. If there is none, then the cut can be made with a hacksaw or other available tool, the main thing is not to damage the geometry and keep the cutting plane flat. The bevel remover is intended for the latter; it is also used to clean the end, in which the reinforcing layer is closer to the inner diameter. Otherwise, this element may form loose connecting holes and cause a leak.

The polypropylene pipe is cut to size using a special knife with a ratchet

Preparation of pipes and fittings

Before welding, the pipes are degreased with alcohol from the outside, and the fittings from the inside. For reinforced products, a special device is used that removes the reinforcing layer - a shaver.

Please note that some manufacturers recommend using a shaver for regular ones because of the possible ellipse of the material in the cut.

Shaver for stripping the top aluminum-reinforced layer

Preparing the welding machine

Although most devices have their own supporting elements, the device should be firmly secured in a vice or clamps to the table. The device is very light, so if unsecured it can easily fall and break, or cause a fire.

We place the coupling and mandrel into the fixed welding machine.

Welding attachments

We set the toggle switch to the required temperature value. For polypropylene this is 270 degrees, but there are times when a lower or higher temperature is required. We take these values ​​from the accompanying documentation for our material and, using the instructions for the soldering iron, select the optimal temperature.

Installing parts for heating

The technology for welding polypropylene pipes implies that when the device has reached operating temperature (the green indicator lights up or the sound signal sounds), you can begin installing the parts to be welded on the pipe welding machine.

We slowly insert the cut into the coupling until it stops; a burr is formed - excess material that rolls into the roller when put on. When putting it on, it is very important to ensure that the burr has the correct shape, without tears or other defects. If the part inserts without visible force or the grant is missing, it may be considered defective and should be replaced. The same applies to the fitting, which must also be put on with visible effort on the mandrel until it stops.

Important! Installation for heating and removal should be carried out by pressing on the part strictly perpendicular to the heating element. Pressing at an angle or removing parts with them moving at a certain angle is prohibited.

Welding

When the elements to be welded are installed in their places, they need to be given a certain time so that the material acquires viscous fluidity and at the same time the polypropylene welding rod does not lose its load-bearing properties. Below are approximate parameters suitable for welding polypropylene pipes of various diameters. It is worth considering that the values ​​are averaged, and the manufacturer indicates more accurate values ​​in the accompanying documentation.

Welding temperature of polypropylene pipes, cooling time, depending on thickness

To navigate the terms given in the table, you should adhere to the following definitions:

1. The heating time is counted from the moment the part touches the stop of the heating element.
2. Connection time is a parameter that shows how long pipes for welding polypropylene should be kept after they have been assembled.
3. Cooling time is the time period that must be maintained for complete hardening and obtaining a monolithic binder.

Assembly of parts

After removing the parts from the heating nozzle, they should be assembled. For connection pvc pipes the fitting is installed at the required angle, and the pipes are connected together in a single movement.

In this case, it is forbidden to turn the parts. We hold the parts, keeping them motionless, but without applying force, as when putting them on.
The time that will pass between withdrawals welding machine, before assembly itself should be minimal. Otherwise, the parts will cool down and will not be welded or the connection will be of poor quality.

Note! For welding large diameter polypropylene pipes 40 – 50 mm, manual methods are not suitable and it is necessary to use a special centerer.

Cooling the connection

An important point when you should not touch the part, including trying to try it on and so on. After cooling, the welded circuit of polypropylene pipes with your own hands is ready for use.

Welding errors

Welding plastic pipes doing it yourself, especially for beginners, will lead to a number of errors. We have selected the most common ones so that you can understand how to weld parts correctly and what you should pay attention to.

1. Rough preparation is the simplest and most common mistake. Improper edge formation, dirt, water and grease at the welding site of polypropylene pipes and similar neglect of preparation leads to the fact that the joint loses its solidity.
2. Positioning errors are defects that occur during assembly. These are attempts to rotate the part after assembly, attempts to remove sagging during assembly. All this means cooling of the parts with a subsequent decrease in the quality of the weld.
3. Wrong material. Here we turn to the features of welding pp pipes. Polypropylene from different manufacturers may have different melting points, which means one of the parts may be underheated or overheated. This problem also occurs when trying to weld two pipes of different diameters.
4. Poor assembly - this includes excessive pressure during assembly, insufficient pressure, an increase in the interval between removing the product from the welding machine and assembly.

All the problems described are quite common and most of them appear due to ordinary negligence shown by the welder. The instructions for welding polypropylene pipes presented above will help you avoid problems, a trial attempt to weld standard joints and processing polypropylene pipes in hard to reach places.

More and more often, metal pipes are being replaced with plastic ones, in particular polypropylene. They have long term operation (up to 50 years), do not rust, do not rot, weigh little, and even you can assemble everything yourself, without involving specialists. Welding polypropylene pipes requires some skill, but it comes quickly. You can first practice on small scraps and inexpensive fittings, and then start creating more serious things.

Types and purpose

Polypropylene pipes can be of four colors - green, gray, white and black. Only black ones differ in their characteristics - they have increased resistance to ultraviolet radiation and are used when laying on the ground. All others have similar characteristics and are laid indoors or buried in the ground.

According to their intended purpose, polypropylene pipes are of the following types:

There are pipes with different characteristics for both cold and hot water. This is displayed in the markings:

• PN10 are used exclusively in cold water supply systems (up to +45°C) with low pressure (up to 1 MPa). They have a small wall thickness. Not suitable for high-rise buildings.
• PN16. They are often labeled as universal, but are more often used for cold water - they can withstand heating of the environment up to +65°C and pressure up to 1.6 MPa.
• PN20. Thick-walled pipes, which can transport media with temperatures up to +80°C, can withstand pressures of up to 2 MPa. Used for distributing hot water and heating systems.
• PN25. These are reinforced polypropylene pipes (foil or fiberglass). Due to the presence of a reinforcing layer, they often have a smaller wall thickness than PN20. The heating temperature of the medium is up to +95°C, pressure is up to 2.5 MPa. Used for hot water supply and heating.

All of them are produced in different diameters - up to 600 mm, but in apartments and private houses they are used mainly in sizes from 16 mm to 110 mm. Please note that the internal diameter is indicated, as wall thickness may vary.

What is welding of polypropylene pipes

Polypropylene is characterized by increased rigidity, and to create systems of the required configuration, fittings from the same material are used. These are various angles, tees, bypasses, adapters, couplings, etc. They are connected to pipes by soldering. This process is also called welding, but its essence does not change: two elements are heated to the melting point and, when hot, are connected to each other. When done correctly, the connection turns out to be monolithic and serves no less than the pipes themselves.

To connect polypropylene with metals, there are combined fittings, in which one part is made of metal and is connected using a threaded connection, and the second - polypropylene - is welded.

What to solder with

Welding of polypropylene pipes occurs using a special device called a soldering iron or welding machine. This is a small metal platform, inside of which there is an electric coil that heats the surface. Because of this design, this unit is also called an iron.

To connect two elements, the spliced ​​surfaces are heated to the melting temperature (+260°). To heat the element to the desired depth, two different Teflon-coated metal nozzles are installed on the welding platform:

The two elements to be connected are simultaneously put on the corresponding attachments, held for a certain period of time (several seconds), then connected. This is how polypropylene pipes are welded.

How to weld

The designs of soldering irons for polypropylene pipes are slightly different, but the principles of working with them are common. There are two main models - with a flat platform or a cylindrical heater. With normal quality, both work, there is practically no difference. Whoever is more comfortable chooses it.

This is what a well-made connection looks like in cross-section - as a single whole

Preparatory work

Before starting work, you need to warm up the soldering iron, but it’s not that simple. The procedure for its preparation is as follows:

• First, nozzles of suitable diameter are installed on the platform.
  • A pin is threaded into the hole in the platform, a mandrel and sleeve are put on it on both sides, and tightened with nuts on both sides.
  • If the heating element is in the form of a tube, the nozzles for it are sold attached to the plate. The plate is placed on the heating element and the fastening bolt is tightened.
• The required heating temperature is set on the regulator. For polypropylene pipes, the welding temperature is +260°C. This is what we set on the regulator and plug it into the network.
• We wait for the signal to set the set temperature. Some models have an audible signal, but mainly the LED lights up or goes out (in different models differently).

The soldering iron is ready for use. But we still need to prepare the pipes and fittings. The first condition for high-quality welding is an even cut. The cut must be strictly vertical, without burrs or tears. This cut can be obtained using special scissors. They have two wide jaws on the bottom that hold the pipe in place, and the cutting part is on top.

The second condition for good soldering of PP pipes is clean, dry, grease-free parts. If you want your plumbing or heating to last a long time and not leak, you should not skip this procedure. Clean the pipe section and fitting using alcohol or water and dishwashing detergent. Then they wait until everything is dry, and only after that they begin the soldering process.

How long to heat

When welding, polypropylene must be heated strictly to the required temperature. Overheating and underheating significantly reduce the quality of the seam. An overheated and softened pipe simply will not be inserted into the fitting, and an insufficiently heated material will not fuse.

The heating time depends on the diameter of the pipes, air temperature and is indicated in the table.

In general, you can solder at +5°C, but the data is given for +20°C. In hotter weather, the holding time of the elements on the soldering iron is reduced by 30-60 seconds, in colder weather it is increased.

Pay attention to the welding depth column in the table. This mark is placed on the pipe. Before that, you will need to press it into the fitting. This creates a small bead of molten plastic in front of the edge of the fitting. This will mean that the seam is made correctly.

One more column requires explanation - “welding time”. This is the time for which it is necessary to compress and fix the elements to be welded.

In general, if you try to insert a cold pipe into a fitting, it should go in with great difficulty - the outer diameter of the pipe is slightly larger than the inner diameter of the fitting. This is done intentionally to provide some excess material from which the bead on the seam is formed. To ensure reliable welding of polypropylene pipes, it is better to take all the components from the same company. This ensures that the sizes match. Otherwise, you need to try it on so that the fitting does not “slip”, but is difficult to tighten.

Technology

As already mentioned, when welding polypropylene pipes, they and the fittings must be cleaned, degreased and dried. And only after that you can start soldering.

This preparation is suitable for all types of pipes, except those reinforced with foil. In this case, after the required piece has been cut, the cut is cleaned down to the foil with a special device - a shaver. A pipe is inserted into it and turned several times. In this case, the top layer of plastic is removed, after which it can be degreased and soldered.

After the surface has dried, a mark is drawn on the pipe, noting the distance to which it must be pressed into the fitting (the easiest way is with a thin marker or a sharpened simple pencil).

Soldering polypropylene step by step

One note: immediately after finishing welding, inspect the nozzles on the soldering iron. If there are material residues, they are removed with a soft, lint-free, non-fading (white) cloth. You cannot leave plastic on the soldering iron - the next fragment will stick and it will be difficult to remove. Do not clean the attachments using abrasives - they have a Teflon coating and are easily scratched. And even microscopic scratches will cause the fragment on the soldering iron (iron) to stick.

By the way, it is better to work with cotton gloves - there will be fewer burns.

Before putting the system into operation, it must be checked. This is done using crimping. Read what it is and how to do it here.

Layout of polypropylene pipes

Polypropylene pipes are used for installation of cold or hot water combs and heating. The choice of diameter in each case is individual - it depends on the volume of liquid that needs to be pumped per unit of time, the required speed of its movement (formula in the photo).

Calculating the diameters of pipes for heating systems is a separate topic (the diameter must be determined after each branch), for water supply systems everything is simpler. In apartments and houses, pipes with a diameter of 16 mm to 30 mm are used for these purposes, with the most common ones being 20 mm and 25 mm.

Counting fittings

After determining the diameter, the total length of the pipeline is calculated, and fittings are purchased depending on its structure. With the length of pipes, everything is relatively simple - measure the length, add about 20% for errors and possible defects in the work. A piping diagram is required to determine which fittings are needed. Draw it, indicating all the outlets and devices to which you need to connect.

To connect to many devices, a transition to metal is required. There are also such polypropylene fittings. They have a brass thread on one side and a regular solder fitting on the other. You should immediately look at the diameter of the pipe of the device being connected and the type of thread that should be on the fitting (internal or external). To avoid mistakes, it is better to write everything down on the diagram - above the outlet where this fitting will be installed.

Next, according to the diagram, the number of “T” and “G” shaped connections is calculated. Tees and angles are purchased for them. There are also crosses, but they are rarely used. By the way, there are corners not only at 90°. There are 45°, 120°. Don't forget about couplings - these are fittings for joining two pieces of pipe. Do not forget that polypropylene pipes are not at all elastic and do not bend, so each turn is made using fittings.

When purchasing materials, agree with the seller about the possibility of replacing or returning some of the fittings. Problems usually do not arise, since even professionals cannot always immediately determine exactly the required assortment. In addition, during the installation process, sometimes it is necessary to change the structure of the pipeline, which means the set of fittings changes.

Polypropylene has a fairly significant coefficient of thermal expansion. If a polypropylene hot water supply or heating system is being installed, it is necessary to make a compensator, with the help of which the lengthening or shortening of the pipeline will be leveled. This can be a factory-made compensator loop, or a compensator assembled according to the diagram from fins and pieces of pipes (pictured above).

Laying methods

There are two ways to install polypropylene pipes - open (along the wall) and closed - in grooves in the wall or in a screed. Along the wall or in the groove, polypropylene pipes are attached to clip holders. There are single ones - for laying one pipe, there are double ones - when two branches run parallel. They are attached at a distance of 50-70 cm. The pipe is simply inserted into the clip and held in place thanks to the elastic force.

When laying in a screed, if it is a warm floor, the pipes are attached to the reinforcing mesh; no other additional fastening is required. If the supply to the radiators will be monolid, the pipes do not need to be fastened. They are rigid and do not change their position even when filled with coolant.

Option for hidden and external wiring in one pipeline (the wiring behind the bathroom was made open - less work)

Soldering nuances

The process of welding polypropylene pipes itself, as you have seen, does not leave much work, but there are a lot of subtleties. For example, it is not clear how to adjust sections when joining pipes so that the pipes are exactly the length required.

Another aspect of welding polypropylene pipes is soldering in hard-to-reach places. It is not always possible to fit a pipe and fitting onto a soldering iron on both sides. For example, we solder in the corner. The soldering iron has to be shoved into a corner, on one side the nozzle rests directly on the wall, you can’t pull the fitting onto it. In this case, install a second set of nozzles of the same diameter and heat the fitting on it.

How to solder polypropylene pipes in hard-to-reach places

How to switch from iron pipe to polypropylene.

Working with polypropylene pipes requires following some recommendations. A properly installed connection is leak-proof and can withstand high pressure.

Difficult to obtain good quality welding at low temperatures. Manufacturers of polypropylene pipes do not recommend welding at air temperatures below 5 degrees. At temperatures below 0, the plastic becomes brittle and the solder may not be airtight. This will lead to leaks or rupture of the pipeline. In the cold season, the place where welding is carried out is warmed up - a tent with a heat gun is installed.

Manufacturers of plastic pipes emphasize that polypropylene products of different brands cannot be soldered. Pipes and fittings from different manufacturers may differ in several respects:

• diameter tolerance;
• softening rate;
• color shades.

An attempt to combine different technical specifications materials leads to difficulties during installation and causes failure of the entire structure.

When laying pipelines, large-diameter plastic pipes (from 63 mm) are welded butt-to-butt. This method is based on heating and melting the ends of the pipes, and their subsequent connection with sufficient force.

It is important that the ends of the workpieces are perfectly straight. This makes it possible to obtain a solder of maximum strength, one-piece and capable of working under high pressure.

Polypropylene pipes with a diameter of up to 40 cm are boiled using a special manual device. Consists of a centering device and attachments for fixing workpieces. The ends of the cut section of the pipe are cleaned with a file or sanding paper. The apparatus is heated, parts of the future pipeline are driven into it and soldered. All movements are done quickly and clearly, until the material is heated to the desired state.

Please note that when using a socket or coupling joint, the outer diameter of the pipe must be greater than the inner diameter of the unheated fitting.

After welding, maintain the time allotted for cooling, do not move or turn over the elements to avoid deformation.

Reinforced pipes are used in heating systems, laying “warm floors” and hot water supply.
Before starting work involving reinforced polypropylene pipes, it is prepared - the aluminum layer is cleaned with a shaver. This is necessary so that during operation, when it comes into contact with water, the aluminum foil does not collapse and the structure does not leak.

The fitting is of a size that the pipe can fit into without the top layers.

Method one

To make a homemade soldering iron you will need:

• hors de combat old iron, which has a retained heating element;
• children's metal construction set;
• rubber handle;
• toggle switch;
• asbestos cord;
• duralumin;
• insulating tape.

In this case, contact of aluminum with liquid is strictly prohibited. This alloy begins to deteriorate, and buying new products is unprofitable. The appearance of small internal distortions in the joints is difficult to notice with the naked eye, however, it is these zones that are the weak point of the entire system. Here it is possible for water to get on the metal surface.

To prevent this, the reinforced layer is carefully cleaned. Such an operation is mandatory if the surface of the pipes is wrapped in foil.

For removing metal sheet a special device is used - the so-called shaver. It has to be purchased separately.

The end is inserted into the device, similar to sharpening a pencil, and they begin to turn.

When working, do not forget about cleaning the aluminum layer. Welding will occur without this procedure, but the reliability of the resulting connection will be quite low.

You can get rid of this human factor by installing fiberglass-reinforced pipes.

If the aluminum reinforcing layer is located in the center of the wall, the surface is trimmed using a special tool. It helps remove the edges of aluminum that cover the end of the pipe. If such an operation is not carried out, water can get into the center of the wall, moving along microcracks in the reinforcing layer, which will inevitably lead to swelling.

In the photograph you can see the soldered connections of the cuts: the incorrect execution in the picture without trimming and the correct one - with trimming.

To achieve the best results, special couplings are used. They seem to “brick up” the ends of the reinforcing layer, which helps to avoid contact of the metal with the liquid.

Some manufacturers give their own recommendations on how to prepare pipes before welding. Even if there is no reinforcing layer, it is necessary to calibrate the outer diameter and then remove the chamfer.

The sizing operation removes the ellipse of the pipe, making it completely round. The removed chamfer facilitates the work of connecting to the coupling. Unfortunately, when PP pipes are soldered independently, these operations are completely ignored.

First, the welding machine must be firmly secured. When heating begins, the parts are subjected to pressure, which is transferred to the soldering iron. To make it more convenient to work, it is important to ensure that the device remains stationary.

A heating couple is placed on the instrument. Next, the desired heating temperature is set and voltage is applied. When PP pipes are welded into sockets, the heating temperature should be within 260±10 °C, which exceeds the values ​​at which polypropylene becomes viscous and fluid.

In this way, the top layer of the pipe together with the fitting quickly melts. As a result, the part can be easily removed without heating the entire wall thickness. At a different temperature, when the elements become soft, the connection will not be possible.

During repairs, various unforeseen situations may arise, for example, the pipeline was accidentally perforated. This problem can be solved provided that the hole is small.

The first option for sealing the structure involves the following steps. First, dry the surface and degrease it. Then we take another pipe from the same manufacturer and heat it and the resulting hole. Next, we seal the hole using a soldering iron or improvised means, for example, a torch. If the pipe is reinforced, the foil must be cut off. But you can also install a coupling.

The second option for soldering a hole in a cylindrical PP product is presented in the video below.

The biggest problem that almost every master faces is the installation of plastic pipelines in difficult areas. To solder polypropylene products in hard-to-reach places, the structure must be divided.

The largest and most inconvenient area is installed first. It is separately formed and then installed in a permanent place.

Upon completion of complex installation, smaller elements are installed. This work must be carried out together with an assistant.

To independently install PP pipes, you must have the appropriate equipment, as well as special skills. If you are not confident in your abilities, it is better to use the services of professionals. The prices can be found below:

• installation of one linear meter pipes - 100 rubles;
• drawing up a drawing and work - 500 rubles;
• trimming a cylindrical product and its subsequent cleaning - 90 rubles.

The cost also includes installation complexity and total volume.

Each stage must be performed according to all the rules.

In order to weld PP pipes, you need to stock up necessary equipment and components. First of all, a detailed project is drawn up, an assembly option is determined, and a decision is made on how to weld a polypropylene pipe with fittings and a mating part of the pipeline. Based on the configuration and geometric shape future pipeline, the welding for the polypropylene pipe is determined, which would be better suited for a specific project and will not entail an increase in construction costs.

During installation, it is possible to adjust the pipe routing, but due to the ease of connection this does not cause any particular problems.

Manual welding of polypropylene pipes does not require a large supply of tools or special skills. Precise adherence to the assembly sequence makes it possible to create a reliable plumbing or heating system that is sealed along its entire length.

Manual welding of pipes is carried out using a compact heating device

Tools and equipment:

• scissors or plastic pipe cutter. Preferable are guillotine-type scissors, with a powerful blade and a toothed force transmission unit;
• stripping tool for reinforced PP pipes. It is a special cutter, and in its primitive form a durable knife with a comfortable handle and a short blade;
• To degrease the surface, it is advisable to use alcohol components. As a rule, ethyl (isobutyl) alcohol is used. Acetone, a very common degreaser for paint and varnish materials, is not suitable for PP pipes - it simply destroys the surface, making it loose and fragile;
• soldering iron for polypropylene pipes is a surface heated to a selected temperature (at least 260 degrees Celsius) - a mandrel - on which nozzles for pipes and fittings are attached. Soldering irons come in tube-shaped and elongated hammer shapes. It is more convenient to weld pipes in hard-to-reach places with a pipe-shaped soldering iron;
• A regular construction tape will help avoid waste of materials. Correctly measured length of the section will minimize the number of cuts and adjustments;
• template in the form of a short piece of pipe of larger diameter. The length of the template must exactly match the depth of insertion of the pipe into the fitting. It is better and more convenient to use a template with a bottom. Butt welding does not require the use of templates.

If the technology for welding a polypropylene pipe for heating is correctly followed, then after the weld has cooled, an even, neat bead is formed, the same in height along its entire length.

• If during operation the parts are soldered incorrectly, it will no longer be possible to separate them. To fix a poor-quality product, you need to completely cut out the area with the seam and make a new one. If soldering was carried out using fittings, their reuse in case of a defect is not allowed, since they are designed for one-time use.
• The main types of plastic connections are butt and coupling. In butt welding, pipes are soldered to each other by melting the ends of each element and their mutual penetration. The coupling method is characterized by the fact that the pipes are connected using special adapters - fittings.
• If you are not going to repair or assemble the pipeline systematically, it is not necessary to buy a soldering iron. You can use rental services or borrow it from friends. If you decide to buy a device for yourself, it is recommended not to overpay for models with a thermostat, since for normal work at home, only one temperature indicator is usually needed.
• When coupling soldering, the fitting is put on the nozzle first, and then the pipe. You need to start counting the time when both parts are put on the attachments.
• Do not cool the finished seam using cold water or cold air. It should cool down on its own without external influences.
• Working with plastic proceeds according to the rules if a slight “overflow” of its part is formed on the coupling.
• You can check the quality of the connection by cutting the pipe in half at the seam. If you did everything correctly, then the seam in the section should be continuous, even, without voids.

How to weld a polypropylene pipe using a welding machine

The sequence of actions when working with a mechanical welding machine is slightly different from working with a hand soldering iron. The technology for welding polypropylene pipes in automatic mode is similar to manual soldering, with the exception that the stripping (trimming) of the pipe occurs using a mechanical saw, and the clamping of the pipes at the soldering site is provided by mechanical grips. The process is called butt welding of polypropylene pipes.

Control of the heating temperature level when welding polypropylene pipes and automatic shutdown of the heating element is provided by the control system unit.

Butt welding of a polypropylene pipe using an automatic unit takes a minimum of time and is characterized by high quality seam joints. Precise welding temperature of polypropylene pipe is another advantage automatic system. This is important for heating systems, but the cost of professional equipment is quite high. But this problem can be easily solved: you can take necessary devices for rent.

Pipe cutting

Cut the material with a tool designed for this purpose. If there is none, then the cut can be made with a hacksaw or other available tool, the main thing is not to damage the geometry and keep the cutting plane flat. The bevel remover is intended for the latter; it is also used to clean the end, in which the reinforcing layer is closer to the inner diameter. Otherwise, this element may form loose connecting holes and cause a leak.

The polypropylene pipe is cut to size using a special knife with a ratchet

Before welding, the pipes are degreased with alcohol from the outside, and the fittings from the inside. For reinforced products, a special device is used that removes the reinforcing layer - a shaver.

Shaver for stripping the top aluminum-reinforced layer

Although most devices have their own supporting elements, the device should be firmly secured in a vice or clamps to the table. The device is very light, so if unsecured it can easily fall and break, or cause a fire.

We place the coupling and mandrel into the fixed welding machine.

Welding attachments

We set the toggle switch to the required temperature value. For polypropylene this is 270 degrees, but there are times when a lower or higher temperature is required. We take these values ​​from the accompanying documentation for our material and, using the instructions for the soldering iron, select the optimal temperature.

The technology for welding polypropylene pipes implies that when the device has reached operating temperature (the green indicator lights up or the sound signal sounds), you can begin installing the parts to be welded on the pipe welding machine.

We slowly insert the cut into the coupling until it stops; a burr is formed - excess material that rolls into the roller when put on. When putting it on, it is very important to ensure that the burr has the correct shape, without tears or other defects. If the part inserts without visible force or the grant is missing, it may be considered defective and should be replaced. The same applies to the fitting, which must also be put on with visible effort on the mandrel until it stops.

Welding

When the elements to be welded are installed in their places, they need to be given a certain time so that the material acquires viscous fluidity and at the same time the polypropylene welding rod does not lose its load-bearing properties. Below are approximate parameters suitable for welding polypropylene pipes of various diameters. It is worth considering that the values ​​are averaged, and the manufacturer indicates more accurate values ​​in the accompanying documentation.

Welding temperature of polypropylene pipes, cooling time, depending on thickness

To navigate the terms given in the table, you should adhere to the following definitions:

1. The heating time is counted from the moment the part touches the stop of the heating element.
2. Connection time is a parameter that shows how long pipes for welding polypropylene should be kept after they have been assembled.
3. Cooling time is the time period that must be maintained for complete hardening and obtaining a monolithic binder.

Assembly of parts

After removing the parts from the heating nozzle, they should be assembled. To connect PVC pipes, the fitting is installed at the required angle, and the pipes are connected together in a single movement.

In this case, it is forbidden to turn the parts. We hold the parts, keeping them motionless, but without applying force, as when putting them on. The time that will pass between removal from the welding machine and direct assembly should be minimal. Otherwise, the parts will cool down and will not be welded or the connection will be of poor quality.

An important point when you should not touch the part, including trying to try it on and so on. After cooling, the welded circuit of polypropylene pipes with your own hands is ready for use.

Before starting work, you need to prepare the installation tool. To create a reliable joint between the structures and all additional parts, you will need a special soldering iron.

It is worth noting that sometimes the connection of products made of polypropylene is called welding. However, this process has many varieties, so it is important to remember that polypropylene pipes are connected in only one way - soldering. For installation of such a system, threaded fittings and metal-plastic are not used.

Soldering polypropylene pipes requires the use of welding machines. There are several types of devices on sale:

• heater with a round cross-section;
• flat unit.

The second type of soldering machine is popularly called an iron, which is largely due to its appearance. Such devices differ only in their design.

For the first model, Teflon nozzles are put on the heater and fixed with parts similar to clamps. In the second device, the same nozzles are screwed to the heater on both sides. The rest of the design elements are no different. The main function of the device is to perform high-quality and reliable soldering of polypropylene products.

The set of soldering devices must include nozzles. The most inexpensive device, the set of which includes a minimum number of elements, is considered to be a Chinese soldering iron. Its power does not exceed 800 W. It is presented for sale together with a stand, as well as attachments that allow soldering of PP pipes with a cross-section of 20-32 mm.

Bimetallic relays work more roughly, as well as capillary thermostats, whose values ​​​​are inaccurate. If compared with thermistor data, the discrepancies will be quite large. Whatever the thermostat, when the device reaches operating mode (judging by the indicator data), you must wait a few minutes. During this time, the temperature of the nozzles will be compared with the one shown by the device.

Now you can start welding. Manufacturers also produce soldering irons that have two heating elements of different power. Each part is equipped with a separate switch.

These products are able to independently achieve the desired temperature. The master himself selects the required power.

The second part becomes a spare in case the first one fails.

The device provides the ability to simultaneously turn on both heaters in order to quickly achieve operating mode.

The equipment can be equipped with auxiliary tools, including:

• chamfer;
• calibrator;
• trimmer;
• pipe cutting scissors.

In some kits you can even find a special cleaning liquid. However, not all of the listed parts are included in the basic package. Often they have to be purchased separately. It is important that the welding machine comes with everything necessary tools for working with any pipe diameters and materials.

Take, for example, a 20 mm pipe. The actual size of its outer diameter will be in the range of 20.3-20.5 mm. A fitting designed to work with a 20 mm product will have an internal cross-section of 19.5-19.7 mm.

Moreover, the middle part of the coupling surface will exactly correspond to the nominal diameter. For a conical plane, 5 degrees are taken.

It becomes clear that if the fittings are not heated, they will not be able to be connected to the coupling.

When the pipe is combined with a hot coupling, the outer part melts. All excess is squeezed out to the top, creating a kind of roller. Next, the inner layers are heated. They begin to compress, and the pipe is able to get into the hot sleeve. A similar effect can be achieved when the fastener element is connected to a hot mandrel.

When the pipe is combined with the fitting, it is elastically compressed, and the connecting element begins to stretch. Heated surfaces are compressed, displacing air. The result is uniform mixing of the molten material.

The general technological process of connecting PP pipes into a socket has several sequential operations:

• cutting of products;
• preparatory activities;
• installation of a welding machine;
• achieving operating mode;
• warming up parts;
• assembly;
• line cooling.

You can manually connect a pipe with a heated tool without much effort if you are welding small parts whose cross-section is in the range of 40-50 mm. To combine cylindrical structures with a diameter exceeding 50 mm, you must use a special centralizer designed for socket welding.

Since soldering polypropylene pipes is not particularly difficult, the work can be done alone.

To cut cylindrical products, special scissors are used that do not allow the pipe walls to wrinkle.

Before starting to solder polypropylene products, the surfaces of the parts are thoroughly cleaned and degreased. Reinforced structures undergo special preparation. Workers installing such products must remember this.

Composite pipes made of PP, which are reinforced with aluminum, are characterized by low thermal expansion. Therefore, a heating system made from such products does not require the installation of additional temperature compensators. Only in such products reinforced with aluminum is oxygen diffusion possible.

In the absence of a reinforcing layer, there is no need to carry out additional special preparation.

When purchasing a tool, you need to choose one that will allow you to perform all the required operations. As a rule, when assembling plumbing and heating with your own hands, you do not need to buy fancy models with a large number of attachments. The power of the soldering iron only affects the speed of its heating, but not the process itself, so there is no point in overpaying.

Note! Inexpensive models come with 3 nozzles for collecting plastic pipes with a diameter of 20, 25 and 32 mm. Pipes of this exact diameter are used for installing internal communications wiring.

Devices for welding polypropylene pipes

The welding soldering iron has quite simple design. The main thing about it is the sole, equipped with heating elements. The sole is equipped with holes of various diameters. You can attach attachments to them, which can be used to solder pipes. The heating temperature is controlled by a thermostat located on the housing.

Using it you can set degrees. Their values ​​are noted in the instructions, and the table is published on the Internet. It is necessary to set the temperature depending on the type of materials being welded. So, for example, for soldering polyethylene pipes a mode of 220 degrees is selected, and for polypropylene - 260 degrees.

In addition to a soldering iron, during work you may need:

1. Roulette.
2. Pencil.
3. Hacksaw for metal.
4. Sharp knife.
5. Scissors for cutting polypropylene.
6. Shaver.

• The welding machine comes with a special stand. A soldering iron is placed on it and plugged into an outlet. But first, a sleeve is inserted into the hole of the soldering iron.
• The ends of the polypropylene are prepared. If it is reinforced with fiberglass, it does not need to be treated. Aluminum-reinforced material will have to be trimmed by chamfering and marking it with a marker. This will help control the depth of immersion of the pipe into the soldering iron coupling.
• First, measure and cut the required section, adding 25 mm to it - they will be inserted into the fitting when soldering.
• When the soldering iron reaches the desired temperature, you will hear a characteristic sound. Then a coupling is inserted into the nozzle on one side, and a prepared pipe on the other.
• The time indicated in the table is recorded. Usually soldering takes from 4 to 10 seconds. While the coupling and pipe are in the soldering iron, they cannot be rotated or moved. You cannot touch them even after the parts are removed from the soldering iron. The accumulated temperature will allow you to create a sealed seam.

As you can see, the technology for welding polypropylene pipes is quite simple. You just need to follow certain rules for making seams.

Here are the main ones:

1. Be sure to remove the chamfer. Otherwise, when connecting, you can lift up the plastic, and the seam will not be airtight.
2. When two parts are connected to each other, they cannot be rotated.
3. Both the fitting and the pipe must be inserted into each other until they stop.
4. Do not clean the nozzle while the soldering iron is on. It is better to remove melted plastic with a rough cloth and pull the cord out of the outlet.

The system assembly process consists of the following steps:

1. Plastic pipes should first be carefully inspected for any surface defects, cracks or weak spots. This must be done before installation begins. It is important to ensure the reliability of the pipes, especially if a hidden heating system will be assembled from them. The markings determine the heating temperature of the pipes.
2. You need to apply markings on the working surface, determining in which places the pipeline branches will be attached. Now, the weak points of the assembled system are identified, in particular, the areas where walls intersect with floors, and the method of inserting into existing communications is also determined. For ease of work, several separate fragments are often welded and then joined together.
3. The tools are being prepared for work. The blade of the pipe cutter is sharpened so that when cutting, a straight, perpendicular end is obtained.
4. Soldering equipment nozzles are cleaned of residual melted plastic and dirt. This can be done after preheating the equipment using a cotton rag or wood chips. By studying the equipment manufacturer's instructions, you can determine how to properly weld, what temperature is optimal to set, and how long to warm up the pipes and other structural elements.
5. The nozzles installed on the soldering iron are heated to the desired temperature until the plastic begins to soften and melt. In this case, the inner side of the fitting and the outer surface of the pipe are glued together, due to which welding occurs. To carry out welding correctly, the heating temperature must be selected based on the cross-section of the fitting and pipe.

If you have a high-quality tool at your disposal, it is equipped with a stable stand, and the heating temperature can be adjusted. This soldering iron is easy to use and practically safe.

When it comes to large-diameter pipes, which are used in heating systems, technological or industrial lines of long length, special automated equipment is used for welding pipes. It controls the temperature and evenly heats the connected sections to the desired levels.

In this way, butt welding is carried out, and the butt seams are strong and airtight.

1. Polypropylene pipes;
2. Special scissors for plastic;
3. Special machine for welding plastic- soldering iron for polypropylene pipes;
4. Liquid for degreasing surfaces. You should not use acetone or acetone-containing products for this, as this component can soften the parts;
5. Fittings (with a coupling connection method);
6. Marker for making marks on plastic;
7. Building level.

Reinforcement

Before soldering the described pipes, you need to find out what type of polypropylene is used in them:

1. Fiberglass reinforced.
2. Aluminum reinforced.

Soldering with your own hands is easier than the first option, and welding in this case is no different from welding ordinary plastic. Pipes reinforced with aluminum must first be cleaned. To do this, you will need a special tool in the form of a sharp knife - a shaver. If black pipes are used, where the reinforcing layer is located between two layers of plastic, for stripping you need to take a trimmer - a narrow knife that will allow you to trim from the end side.

Choosing pipes for heating

When selecting heating nozzles, it is necessary to take into account the diameter of the pipes being connected and other important points:

• strength;
• how well the shape is retained after temperature changes;
• thermal conductivity.

Almost all welding machines are suitable for various attachments. This is very convenient when it is necessary to install a complex highway.

Each wearable element has two ends. On one, the outer side of the part is heated, on the other, its inner part. All nozzles are coated with Teflon, which protects the surface from the adhesion of molten material. The dimensions of the parts are in the range of 2-6 cm, which corresponds to the common diameters of cylindrical products.

Choosing a material for heating installation is actually not that difficult. Modern market offers four options, and each has its own marking:

• Polypropylene under the PN 10 brand is intended for assembling a “warm floor” system and cold water supply.
• Brand PN 16 can be used for cold water supply and heating installations in which the coolant circulates under low operating pressure.
• Brand PN 20 is a universal option, capable of withstanding a working pressure of 2 MPa and a coolant temperature of 80 degrees.
• Brand PN 25 is a reinforced polypropylene pipe, suitable for installation of heating and hot water supply systems with a coolant temperature of up to 95 degrees.

Important rules for soldering polypropylene

There are many points that should be taken into account when working with polypropylene pipes. Failure to comply with them leads to a decrease in the quality of connections of fittings and tubes, leakage and blockage of the system.

1. Deviation from the installation rules for PP products. If the pipe is not inserted into the fitting all the way and a gap forms between their walls, then the usual loads for such a connection may be too high, which will inevitably lead to leaks.
2. Strong pressure when connecting elements. When inserting the molten edge of the pipe into the fitting, the pressure should be minimal. Excessive force applied leads to the formation of plastic melting inside the pipe, its blockage or reduced permeability.
3. Incorrectly selected material. A structure made of low-quality plastic pipes, even with skillful installation, will not last long. Purchase polypropylene products only from trusted suppliers and a good brand.
4. Connecting pipes from different manufacturers. Regardless of the quality of plastic pipes, it is impossible to connect elements made by different manufacturers.
5. Removing melts during the welding process. This is not recommended - any movement before the plastic hardens will lead to even greater deformation.
6. Slow pace of work. After heating, polypropylene cools down in a matter of seconds, so it is very important not to be distracted and to connect the parts with precise movements within the allotted time.
7. Dirty welding machine. Before starting work, the Teflon surface of the device must be checked and, if necessary, cleaned of adhering plastic residue or dirt.
8. Remaining liquid in the pipe. Do not allow water to enter the pipe; when heated, the drops will turn into steam and the connection will lose strength.

When working with polypropylene pipes, remember that the heated material has a very high temperature. Take precautions: wear a robe and thick gloves to protect your skin in case of contact with hot plastic.

No repair or construction is complete without the installation of plastic pipelines. Carry out all work according to the instructions and polypropylene pipes will serve for a long time and reliably.

At the end of the fixation phase, all layers of the welded joint lose their plasticity, and now the finished part can be placed on the table. But the part acquires its full strength only after all layers of the welded joint have cooled to a temperature of 40ºC. The estimated cooling time for connections of different diameters is also indicated in Table 1.

Thus, the welding time of polypropylene pipes can be determined as the sum of the time of heating, rearranging, fixing and complete cooling.

Table 1 Technological intervals for socket welding of polypropylene pipes and fittings (according to DVS 2207-1)

Of course, in order to end up with a correctly functioning and durable system, you need to strictly adhere to the rules and technology for working with PP pipes. And the sequence of actions will directly depend on the purpose of the project.

The following types of connection are distinguished:

• Coupled - in this case, polypropylene pipes are welded at their end parts with a coupling fitting. In this case, the inner part of the coupling and the outer surface of the PP pipe are heated and combined - the process is called “socket welding”. If the heating temperature is observed, welding polypropylene pipes in this way is reliable and airtight. This method is used most often.
• Direct docking. At the same time, the ends of adjacent branches of polypropylene pipes are connected. Usually, this method used for installation of lines made of large diameter pipes (from 40 mm or more).
• Welding of PP pipes using professional equipment. This method is practiced if you need to combine pipes of large cross-section. The welding seam in this case is very strong and reliable. Provided that the heating temperature and the degree of clamping are selected correctly, it can be argued that the pipes will be connected absolutely hermetically.
• Pipeline installation using fittings clamping or self-locking type. This type of fastening is relevant for main lines in which the pressure level is quite low.
• Cold welding method. To do this, use adhesive mixtures or compositions with a high degree of adhesion that harden quickly. These materials can provide reliable fastening and seam tightness. In addition, this technology for welding polypropylene pipes for heating is very relevant if it is impossible to use electrical equipment.

It is worth noting that the durability and reliability of welding seams also depends on the class of equipment used. In addition, before starting work, plastic pipes must be cleaned of water, dirt and any greasy stains, and the end cuts must be checked for smoothness and evenness. It is also important that during welding of PP pipes the melting temperature of the plastic is reached, otherwise the seams will not be airtight and durable.

The technology for welding polypropylene pipes is called coupling or socket welding. The pipes are connected not joint to joint, but with the help of fittings - additional conductors, which are used to solder the edges of the pipes at a temperature of 260 degrees.

When installing a plastic pipeline, it becomes necessary to cut polypropylene pipes in the middle or at the ends in order to adjust them to size and dock with each other. There are several cutting methods - each requires a separate tool:

1. Battery-type pipe cutter is a scissors equipped with an electric drive. High cutting speed is their main advantage. You will spend about 5 seconds on each pipe. The downside is restrictions on the diameter of the cut workpiece.
2. Roller-type pipe cutter - the principle of operation of the tool resembles the operation of a seaming wrench for preservation. The cut with the tool is smooth, without torn edges. They make several turns around the pipe, then tighten the hard alloy roller and turn it a few more times. The downside is that it cannot be used if the pipe is adjacent to the wall and cannot be removed.
3. Professional scissors for cutting plastic pipes - consist of an upper sharp knife and a lower holder. The device is easy to use - mark the desired length on the pipe, place it between the blades and cut it. The edge will be smooth, without crumbs or scraps.
4. An electric jigsaw is a convenient method, but it can give a slight bevel, so the tube is cut by turning it several times.
5. Grinder of any power - cut the plastic without applying strong pressure, use a metal disc.

After trimming, the end of the polypropylene pipe is treated with sandpaper to remove all possible burrs and snags.

1. The welding machine must be installed on a special stand - a clamp.
2. Make sure that the contact surfaces of the device are free of dirt. If excess particles or dust adhere to them, clean the Teflon layer with a rough cloth soaked in alcohol.
3. Set the temperature sensor to 260 degrees.
4. Connect the welding machine to the mains and press the power button.
5. Heating occurs in no more than 15 minutes, depending on the ambient air temperature.

After cutting and marking, the pipes are ready for welding. You can proceed to the next stage - heating the parts.

How to weld polypropylene pipes - technological methods

Rice. 4 Pipe heating

Obsolete, heavy and very difficult to install metal pipes are used less and less for various purposes. They are gradually being replaced by modern, high-quality products made from synthetic materials. In this article we will talk about how polypropylene pipes are welded and present their main advantages over other analogues.

Polypropylene pipes are used mainly for installation heating system and water communications. The technology of their welding, with special tools, is not difficult and can be performed even by a beginner in the construction business. Please note that it is acceptable to use plastic pipes in the temperature range between -10℃ and 90℃.

We put the parts to warm up

When the welding machine reaches operating mode, the light will light up. The pipe is inserted into the coupling, and the fitting is inserted into the mandrel. If it is quite difficult to carry out such work at the same time, a heavy connecting element is installed first.

Welding parts necessarily have a small allowance, which begins to squeeze out during their installation. This creates a ring-shaped roller (burr). To move such a ring, you need to make some effort, but this should be done smoothly and slowly so that the burr takes on the correct shape. A fitting that fits loosely onto the mandrel and does not form an annular bead is considered defective.

When installing the part, be sure to monitor the installation depth. As soon as the element rests against the top of the mandrel, you need to stop applying pressure, otherwise you can damage the end of the pipe and crush the fitting stop. To control the depth of immersion of the part into the coupling, a corresponding mark is made at some distance from the end. However, this procedure is not necessary since the fitting is basically inserted into the mandrel until it touches the stop.

After the parts have been installed in the apparatus coupling and its mandrel, you need to wait a few seconds until the surfaces are well melted. It is important to determine the heating duration correctly. This time should be enough to obtain a viscous and fluid state of polypropylene.

If the heating period is too long, the parts will become very soft. Manufacturers of plastic pipes have developed special tables that indicate the heating time for a specific brand of polypropylene. In this case, the wall thickness and cross-section of the pipe are also taken into account.

When fittings are combined with cylindrical products, the angle of rotation of the parts should not exceed 5 degrees. If the joint is made correctly, the flash will have the same thickness on all sides.

Method of manual welding of plastic pipes

An industrial hair dryer for welding polypropylene pipes is used in several cases:

• for connecting two sections of pipe;
• for the manufacture of shaped parts;
• for mounting an elbow from individual elements.

When soldering plastic, a construction hair dryer is equipped with a reflector - a nozzle with a special coating to which the molten material will not stick.

Having installed the hair dryer on the table surface, set it to the minimum air flow. The nozzle is heated to a certain temperature and the ends of both plastic blanks are pressed against it. Immediately after the polypropylene softens, the pipes are connected to each other.

The combined parts are held in this position for up to 30 seconds. This time is enough for them to stick together and harden.

As a result of welding with a construction hair dryer, the connection is strong and reliable.

Among the main advantages of polypropylene pipes are:

• durability;
• wide temperature range of use;
• small weight of products;
• convenience and speed of installation;
• no corrosion of the internal surface;
• their cost is comparable to their metal counterparts.

International marking with the letter designation of polypropylene PN and digital values ​​indicates the pressure level acceptable for operation of this product. In addition, from the markings you can find out exactly how to weld polypropylene pipes and for what purposes they can be used.

In particular, if we are talking about a heating system, then the products and welds must be strong enough to withstand the conditions of permanent heating and high pressure.

It is worth noting that plastic pipes will serve for a long time and without failures if you provide them with the right conditions operation. They should be placed away from sources of direct thermal radiation - heating boilers, sunlight, industrial devices. In addition, the reliability of the connections will be guaranteed if the temperature for welding polypropylene pipes is properly observed, as well as with a minimum number of elements joined end-to-end.

Before starting any work, you should start designing the future system. At this stage, they work out the layout of the structural elements, determine the sequence of assembling the system, and also decide how the welding of fittings and polypropylene pipes and insertion into the mating part of the pipeline will be carried out.

Then you need to decide how the pipes themselves will be welded together - this depends on the geometry and configuration of the future pipeline. In addition, they calculate the number of required swivel fittings, couplings, tees and other auxiliary elements that will need to be purchased before starting work.

During the work process, the possibility of some changes in the wiring diagram cannot be ruled out, however, this will not be difficult to do, because the assembly of PP pipes is very simple and convenient.

If you carry out all the work manually, then you will not need particularly complex tools or professional skills. The main thing is to adhere to the installation diagram and sequence, and then the heating, plumbing or other communications will be completely sealed and of high quality.

The list of tools for work looks like this:

• Cutter or scissors for cutting plastic. Guillotine-type scissors, equipped with a toothed force transmission unit and a strong blade, are optimally suited.
• A device for stripping reinforced polypropylene pipes - this can be a simple knife with a short, strong blade.
• Alcohol (ethyl or isobutyl) – it will be needed to degrease the surface of the pipe before welding. Acetone, a degreaser popular when working with paints and varnishes, cannot be used for PP pipes, as it will make the surface porous and fragile.
• A welding tool, that is, a special soldering iron for PP pipes. It looks like a surface capable of heating up to 260 ℃ (mandrel), on which sockets for fittings and pipes are attached. There are soldering irons that are tube-shaped and those made in the shape of an oblong hammer. In the most inaccessible places it is more convenient to operate with a pipe-shaped instrument.
• Tape measure for measuring the length of sections so that you can cut materials as accurately as possible without subsequent adjustment and trimming;
• A template made from a short piece of pipe with a large diameter and, preferably, with a bottom. Its length must exactly match the depth of immersion of the pipe into the fitting. You don't need a template for butt joints.

If all work on welding polypropylene pipes and other structural elements was carried out accurately and correctly, the result, after the seam has completely hardened, should be an even side, the height of which is the same around the entire circumference.

It is worth noting that if the heating temperature is violated and an influx of excess molten plastic occurs in the inner part of the pipeline elements, the internal diameter of the pipe will be reduced. This will lead to an increase in pressure inside the system and a deterioration in the passage of water or coolant through the pipes. Consequently, the quality of joining seams also depends on the conscientiousness of the approach to work.

Cooling the connection

This tool is called a shaver and is widely used when working with reinforced pipes. For ease of installation, the socket of the fitting is made in such a way that it allows connection only with a shaver-treated pipe. The depth of stripping of the pipe is determined taking into account the depth of the socket of 2 mm.

If it is necessary to correct the work performed, the technology allows this to be done within a few seconds. The parts should not be subjected to any pressure until the material has completely hardened, which lasts approximately 2-4 minutes.

Approximate parameters for the duration of welding operations can be viewed in a special table. More exact values indicated by manufacturers of fittings and PP products.

In order to install the system correctly, it is necessary to accurately follow the installation technology of PP pipes. The intended purpose of the project determines the sequence of assembly of the system and how to properly weld (cook) a polypropylene pipe.

Types of docking:

• coupling connection - in this case, the end part of the PP pipe is spliced ​​with the continuing outlet using a fitting in the form of a coupling. In this case, the technology most often used for welding polypropylene pipes is when the outer surfaces of the polypropylene pipes and the inner surfaces of the coupling are heated, the so-called “socket” welding. The result is a strong, reliable and hermetically sealed connection, subject to all welding stages and heating temperatures. The method of socket welding of polypropylene pipes is the most common;
• butt connection. The surfaces to be welded are the end sections of the leading branch and the mating part of the polypropylene pipeline. Butt welding is most often used when laying large diameter pipes (40mm and above).
• The technology for welding large-diameter polypropylene pipes involves the use of special, professional equipment. The connection is highly durable. If the temperature and clamping force are chosen correctly, the connection is sealed;
• connection using clamp or self - locking fittings . It is rational to use for main pipelines with low pressure levels;
• cold welding of polypropylene pipe.

The use of adhesives and quickly hardening components with high adhesion to create durable and airtight seams.

Small diameter pipes are most easily connected using fittings

Cold welding allows you to solve the problem of how to weld a polypropylene pipe for heating in places where it is not possible to use electrical equipment.

The development of the system configuration allows for the design of a pipeline diagram of any complexity and configuration. Welding of this type of pipe is done “for centuries”; in the future it will be impossible to disconnect the welded joint.

Butt welding of polypropylene pipes

When soldering PP products end-to-end, the ends of the parts are heated with a hot tool until they melt. Then the elements are pressed with force until the seam cools. This technology is distinguished by its simplicity.

For all its simplicity, butt welding only seems so accessible. In practice, this requires solving several problems, which is almost impossible to do in everyday conditions.

The pipes must align exactly along their axis, with only a 10% deviation from the wall thickness allowed. Pressure on the parts that press cylindrical products to the plane of the heating mirror when exposed to high temperature should be applied only for a certain time. This is the only way to achieve a high-quality connection. When performing trimming, it is necessary that the end has perfect perpendicularity.

The conditions listed above are quite difficult to follow without an additional device - a special centralizer. It is equipped with an electric drive that creates a certain compression force. In addition, this device is equipped with a trimmer.

In other words, to carry out butt welding of small-diameter polypropylene pipes, you will need a larger amount of special equipment compared to the previous joining method. Considering the fact that when socket welding, a better joint is obtained due to lock connection, home craftsmen prefer to use this particular method of combining pipes.

Butt welding of PP products is mainly used in production, when it is necessary to connect structures of large cross-section when installing a straight section of an engineering structure made of cylindrical products.

According to statistics, more than 70% of pipeline systems today are made of polypropylene, no matter whether we are talking about installing a new pipeline or replacing an old system. The technology of welding polypropylene pipes, which must be followed to the smallest detail to achieve the desired result, is an integral part installation work.

It is this aspect of the organization of pipeline systems that this article will mainly focus on.

Why polypropylene pipes

Primarily because polypropylene pipes have the best combination of quality, price and requirements for installation and operation. Pipes of this type are strong, corrosion-resistant and durable.

Thanks to the listed qualities, polypropylene pipes can be used in various fields:

• as a material for water and gas pipelines;
• for gutters;
• as a material for pipelines used to transport various types of aggressive media.

It is the technology of connecting polypropylene pipes by welding that serves as the most reliable and fastest method of installation, including other types of plastic pipes.

A set of tools for welding polypropylene pipelines

The tool kit for welding polypropylene pipes looks approximately as follows:

• an electric welding machine with a movable electric drive for polyfusion welding, equipped with welding nozzles of the required sizes;
• contact thermometer;
• special scissors or pipe cutter;
• alcohol or any other degreaser;
• rags (made from natural material);
• roulette;
• marker;
• mounting device for welding elements whose diameter exceeds 50 mm;
• scraper.

The kit for welding polypropylene pipes may also include tools available in almost every home - a knife, a metal file, if special scissors or a pipe cutter are not available.

Preparation for welding polypropylene pipes

1. Heating nozzles are tightly attached to the welding machine and, having set it using the regulator at a temperature of 250-270 degrees, turn on the device. The heating time of the welding machine depends on the ambient temperature. To avoid damage to the Teflon layer of the nozzles when heated, they are first cleaned with a rag made of non-synthetic material.
2. Manipulations with the welding machine begin when, using a contact thermometer and indicator, it is determined that the device has been heated to the desired temperature.
3. Check the functionality of the cutting roller or special scissors by making 2-3 cuts on an experienced pipe trimmer. The cut should be perfectly equal, without depressions or protrusions. Otherwise, the tool must be sharpened.
4. Before welding begins, all elements are carefully inspected. The walls of the parts must not be weakened in any way; the closing parts (fittings) must be functional. Their threads are checked with a part with the opposite thread.
5. Pipe sections and welding fittings into which pipes are inserted are cleaned and degreased. The fittings are placed on the frame and checked to see if they are too loose. Fittings that are loose on the frame are rejected.
6. Pipe elements of the required length are measured and cut. If a metal saw is used for cutting, the ends of the pipes must be additionally cleaned of burrs.
7. Using a special device or a sharply sharpened knife, bevel the pipe wall at the end being prepared for welding at an angle of 45 degrees. This applies primarily to pipes of large diameters (more than 40 mm). This bevel will help avoid material scuffing when inserting the end of the pipe into the fitting.
8. Before welding large-diameter parts, their ovality must be checked.
9. Before starting welding, remove the oxidized layer from the pipes along the entire length of the joint, as it can adversely affect the quality of welding.
10. First, insert the pipe into the fitting and mark the entrance boundary (depth) with a marker. Here it is taken into account that the pipe should not be pushed into the fitting coupling all the way. To avoid narrowing the cross-section of the pipe at the seam, leave a gap of at least 1 mm.

Time table for welding polypropylene pipes depending on their diameter

Instructions for welding polypropylene pipes

Immediately before welding the pipes, the elements to be joined are degreased again, since without this it is simply impossible to achieve an ideal connection.

How to properly weld polypropylene pipes:

1. First, put the fitting on the heated nozzle, since it takes a little longer to heat up compared to the pipe due to its thicker walls. Check that the fitting fits equally tightly to the nozzle along its entire length.
2. Next, a pipe is put on the second nozzle and also checked for a tight fit.
3. Wait for the parts to heat up. If the parts to be welded do not fit tightly to the nozzles, they are turned until a tighter contact is obtained, but no more than 10 degrees.
4. The welding time for polypropylene pipes is calculated according to the table given, depending on the diameter of the pipeline.
5. After heating is completed, remove the pipe and fitting from the nozzles and then connect them with a uniform, slow movement without turning along the axis, inserting the pipe into the fitting to the mark to the full depth.
6. Hold the parts for a few seconds until the seam cools and the polypropylene loses its elasticity.

Welding polypropylene pipes with electrofitting

The welding machine is prepared in the same way as for polyfusion welding.

Technology for installing polypropylene pipes using electrofitting:

1. Cut the pipes into pieces of the required length using the available tools.
2. Inspect the pipes and prepare the welding machine.
3. Clean the oxidized layer and degrease both the outer surface of the pipes and the inner surface of the electrical fitting.
4. Make a mark where the pipe enters the fitting.
5. Insert the pipe into the electrical fitting and securely fix the parts in this position, since during heating the volume of polypropylene increases, as a result of which the pipe is pushed out of the fitting under pressure.
6. Connect the electric welding machine to the network and wait for it to heat up to operating temperature.
7. Connect the welding machine to the electrical fitting with contact wires.
8. The welding process is started by pressing the “start” button, and it is turned off automatically.
9. The correctness of the welding process is judged by the control points on the fitting, through which the ejection of plastic can be seen.

Polypropylene pipes: how to install the parts to be welded into the nozzles of the welding machine

Upon completion of welding of polypropylene pipes, the connection must be maintained until completely cooled. The cooling process of the joint should occur naturally. After the parts have cooled, they will set, as they say, “tightly.”

The parts must be connected in such a way that “noises” do not form outside and especially inside the pipes, which can lead to a deterioration in the conductivity of the pipeline.

Compared to metal pipes, plastic products are connected much stronger and, accordingly, more reliably. Almost any section of the polypropylene piping system can be replaced without the need to dismantle the entire system.

The welded joint must be used at least 1 hour after the last weld is made.

Advice! It is important to allow the weld to fully cool and set, as this will affect the future ability to withstand the required loads. In addition, during cooling, the junction must be freed from any mechanical influences (compression, rotation, pressure, etc.).

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Cold welding method for polypropylene pipes

Polypropylene pipes can also be joined independently by cold welding - using aggressive glue:

1. In this case, the pipes are cut and prepared using a method similar to the method used in conventional welding.
2. Fittings and pipes are preliminarily marked in accordance with the correct position of the parts (in accordance with the wiring, with the correct horizontal angle, etc.).
3. Apply glue to each of the parts to be joined, after which they are quickly connected and pressed.
4. The elements are fixed in this position for 15 seconds.

Water supply can be carried out no earlier than an hour after the completion of the pipeline installation work. During this hour, complete immobility of the system must be ensured.

It should be noted that adhesive connection Polypropylene pipes are not inferior in strength to welded pipes. However, connecting plastic pipes in this way is only suitable for cold water supply.

If the purpose of the system is to transport gas or hot water, the pipeline must be made of metal pipes, or polypropylene pipes must be connected using one of the methods described earlier.

Typical mistakes when welding polypropylene pipes

If, when connecting a fitting and a plastic pipe, the pipe is not inserted to the internal stop (the gap will be significantly larger than 1 mm), then a gap will remain between the internal stop of the fitting and the end of the pipe.

On a pipeline prepared for operation, this gap will be a section with a wall of smaller thickness and, accordingly, a larger internal diameter compared to the original pipe. In this case, the design pressure of this section will be lower than that of the remaining parts of the pipeline, i.e. the site will become a “weak link”.

Another typical mistake is excessive force when combining a heated pipe with a fitting. In this case, an internal bead is squeezed out between the internal stop of the pipe and the end of the pipe, subsequently creating a noticeable obstacle to the transported medium.

Technology for welding polypropylene pipes: technology, time, required kit, how to solder correctly

Do-it-yourself technology for welding polypropylene pipes: overview of methods + installation example

Repair or replacement of communications made of polymer pipes cannot be done without carrying out a procedure such as welding. How to properly weld polypropylene pipes with your own hands and what to consider when joining elements, we will consider in the article.

Pipes and auxiliary elements for assembly

One of the undeniable advantages of polymer pipes is their ease of assembly.

Installation of elements can be done almost anywhere: laying open method on the walls or placed hidden under the floor.

Polymer pipes are produced with diameters from 20 to 110 mm. For household purposes, products of sizes 20/25/32/40 mm are most often used. The area of ​​application determines the nominal pressure of the material. In the marking it is designated by the letters “PN”:

• PN 10 - chosen for the installation of cold water supply.
• PN 16 - used for cold water, but with higher pressure, as well as when installing a “warm floor” system.
• PN 20 – products, the only limiter of which is the temperature regime of the liquids transported through them. It should not exceed 75 °C.
• PN 25 are universal products used for the installation of both “cold” and “hot” systems, the temperature of which reaches 90°C.

On sale you can find polymer products equipped with additional reinforcement.

The main feature of polymer pipes is their inability to bend. Therefore, all changes in the trajectory of the laid highway are carried out only from straight sections connected to each other by auxiliary fittings:

• crosses - for the possibility of branching the main flow;
• tees – flow multipliers;
• couplings - for connecting pipes in a straight section;
• bends - for changing the direction of the pipeline.

Fittings can be equipped with fused metal threads, which make it possible to connect a polymer pipeline with metal elements.

When choosing auxiliary elements, two parameters should be taken as a basis: the internal cross-section of the products and the thickness of their walls. These parameters must correspond to the technical characteristics of the polypropylene pipes used.

Methods for connecting polymer pipes

When joining pipes made of polymer materials, depending on the installation conditions, one of two methods is used:

1. Soldering involves heating and joining the molten ends of elements.
2. Without soldering - involves connecting pipes using compression fittings or by implementing the so-called “cold” welding.

The second installation method is convenient in the sense that there is no need to use special equipment to implement it. All work can be done using simple tool– crimp key.

Connection Tools

The main tool used to join plastic pipes is a welding iron. This is a kind of soldering iron that operates from a 220V network. The principle of operation of the device is quite simple. The role of the heating element of the iron is performed by a welding heating element placed in a metal casing. It heats the stove to a predetermined temperature, which heats the nozzles. The thermostat is responsible for maintaining the optimal temperature of the nozzles.

The iron comes with heating pads standard sizes. Heating to a certain temperature, they soften propylene to a viscosity that will ensure a tight connection of the elements. Nozzles are selected depending on the diameter of the pipes used:

• Size 20 - for pipes with a diameter of half an inch;
• 25th – for products with a diameter of 0.75 inches;
• 40th - for elements with a cross section of 1.25 inches.

Since the cost of such a welding machine is quite high, and it is not necessary to use it very often, there is no point in purchasing equipment. It is better to rent the tool for a day or two.

For high-quality cutting and preparation of welded areas, it is best to use a special tool designed for this purpose - a pipe cutter. With its help you can get an even, smooth and beautiful cut.

In the absence of a pipe cutter, the work can be done with a grinder or a hacksaw. The only thing is that after such tools a fringe remains at the cut site. But it won’t be difficult to remove by sanding it with a strip of sandpaper.

In addition to the basic tools for the work, you will also need:

• square;
• construction tape;
• a simple pencil or marker.

When planning to connect pipes using the “cold” welding method, it is necessary to purchase in advance a thermoactive adhesive made on the basis of polyester or epoxy resin, or its thermoplastic analogue made on the basis of rubber.

Main stages of soldering technology

The key conditions for successful installation of a plumbing system made of polymers are careful calculation of the required material and competently performed welding of the elements.

Calculation of volumes of material and components

To make your work easier, thereby minimizing errors during installation, the first step is to draw a diagram of the future system, indicating on it the number of turns and branches. When calculating the number of pipes, 25-40 mm spent on “penetration” should be added to each length of the segment.

If you have never welded polypropylene pipes, experienced specialists recommend purchasing several pieces of pipe for preliminary training. Such costs will be inexpensive and will allow you to avoid gross mistakes when installing the system.

A feature of polymer pipes is the increase in the coefficient of linear expansion under the influence of high temperatures. As a result, when heated or pressure increases inside the system, the pipes elongate and begin to sag over time. To prevent this phenomenon, when laying sections longer than 4-5 meters, it will also be necessary to use compensators.

Compensators are installed on both horizontal and vertical sections, mounting them between two fixed supports. If necessary, special modifications of compensators can be purchased that can eliminate linear expansion at corner bends of the pipeline.

Let's find out how to properly weld polypropylene pipes so that there are no leaks at the joints.

Soldering of pipeline elements

Briefly, the essence of the technology for welding polypropylene pipes is that, under the influence of high temperature, the ends of the joined elements are heated and connected by tightly pressing them together.

Before starting work, pieces of pipes cut to the specified length eliminate irregularities and burrs. If the pipe has a layer of internal or external foil, it must first be cleaned with a trimmer equipped with well-sharpened and adjusted knives.

When stripping using a trimmer, the pipe must be buried into the tool until it stops.

The work of welding plastic pipes with your own hands is carried out in the following sequence:

1. Connect the soldering iron to the power supply in order to heat the equipment to the optimal temperature of 260-270°C.
2. The pipe sections to be connected are simultaneously put on the nozzles, ensuring the most even fit. This work must be performed quickly and confidently.
3. After waiting the time specified in the instructions until the fittings and pipe ends melt, remove the elements from the heating nozzles.
4. Dock the molten ends together, gently pressing them into each other for 15-20 seconds.
5. The fastened parts are left in a static position so that the seam cools completely and the joint becomes monolithic.

You can determine the heating duration from the instructions supplied with the equipment or using the table below.

The heating time requirements indicated in the table cannot be ignored. Insufficient heating is not able to ensure a reliable connection. Excessive overheating will cause the polypropylene to “leak” and parts to become deformed. As a consequence: protrusions are formed on the inner surface of the welds, which will significantly reduce the diameter of the pipeline.

After polymerization is complete and hardening, which takes about 20 seconds, the joint is ready. Using the same technology, all subsequent nodes are soldered until the bitter end, until the water supply system is completely assembled.

Typical installation mistakes

The main mistakes that novice craftsmen make when working with polymer products:

1. Heating of parts. During heating, the parts should be positioned as level as possible. The slightest displacement can negatively affect the performance parameters of the entire plumbing system.
2. Joining of polymerized ends. When applying pressure to the molten ends of the elements, you cannot rotate the parts around their axis. This may result in the seam not being strong enough.
3. Alignment adjustment. When joining elements, only a slight adjustment of their alignment is allowed, the duration of which is no more than 1-2 seconds.

Another important point: when soldering taps, it is necessary to take into account the location of the valves, ensuring they have free full movement.

If, after joining the elements, there are doubts about the quality of any seam, it is better to cut out the joint and redo it again. It is better to eliminate defects at the stage of installation of the structure, since replacing a leaking joint in a neglected system is much more problematic.

Assembling elements without soldering

The use of compression fittings and modern adhesives makes it possible to install polypropylene pipes efficiently, quickly and with minimal material investment.

By installing a compression fitting

To implement this connection method, you will need to purchase compression fittings and use a crimp wrench.

Installation of a compression fitting includes three main stages:

1. Place a blue nut on the end of the pipe, cut at a right angle and cleared of burrs. When placing the ferrule white it must be given a position in which the thickened part is directed towards the tail of the pipe.
2. The pipe is inserted into the fitting until it stops, pushing the clamping ring to the maximum.
3. Tighten the blue nut, “tightening” it first by hand, and then tightening it with a wrench.

Assembly of compression fittings does not require special knowledge or skills. Products are supplied for sale completely ready for installation. Their installation can be performed under any temperature conditions.

By gluing elements

The adhesive method is used to assemble a water pipeline through which it is planned to transport only cold water. To apply the “cold” welding method, you will need to use an “aggressive” adhesive composition such as LN-915.

To protect the skin of your hands from accidental contact with the composition and “corrosion” by its active components, it is better to perform gluing operations while wearing protective gloves.

Sequence of actions when gluing products:

1. Check the correspondence of the cut angles of the joined sections and mark the places for gluing with a pencil.
2. Clean and degrease the ends of the pipes to be connected.
3. An adhesive composition is applied evenly to the ends of the pipes and the area of ​​the fitting sockets.
4. The pipe sections are inserted into the fitting holes, focusing on the marks made in pencil. The structure is kept in a fixed position for three minutes, after which excess compounds are removed with a napkin.
5. The combined elements are laid out on a flat surface and left for 5-6 hours until completely dry.

You can run water to check the quality of gluing only a day after completion of installation.

When implementing this method, it is important to observe two main conditions: temperature and humidity conditions. All work must be performed at an air temperature of +5, +35°C. When gluing in hot weather conditions, the work should be done as quickly as possible so that the glue does not have time to dry before installation is completed.

Do-it-yourself technology for welding polypropylene pipes

Manual and mechanical welding of polypropylene water pipes

High-quality, practical and durable pipes made of synthetic materials replace less durable, massive and difficult to install metal pipes. Plastic pipes are used for the installation of heating systems and water mains. The main advantage is that high-quality welding of polypropylene pipes with your own hands, with the necessary equipment, is accessible even to non-professionals. The safe operating temperature for plastic pipes is from -10 to + 90 degrees Celsius.

Water supply and heating systems are created from polypropylene pipes

Advantages of polypropylene pipes

Long service life, high coolant temperature and no corrosion on the internal walls, low weight and a quick method of welding polypropylene pipes are the main advantages of polypropylene (PP) pipes. The cost of a reinforced plastic pipe, which is used, for example, in heating systems, is comparable to the price of a metal pipeline, but its durability is much greater. Even a novice installation engineer knows how to weld a polypropylene pipe correctly.

The marking code for polypropylene pipes, adopted by manufacturers all over the world, is the letter designation PN, which means “polypropylene,” and a digital code indicating the maximum operating pressure of the pipe. The marking indicates where the product can be used and how to properly prepare heating from a polypropylene pipe of this type.

Installed heating pipes must withstand significant pressure, taking into account constant heating.

Technical characteristics of pipes are indicated on the outside of the product

In the absence of direct heating of the outer side of the polypropylene pipe from heat sources - a heating boiler, direct sunlight, industrial equipment - the water supply system will operate without failures. Temperature is also important; welding a polypropylene pipe with your own hands will be flawless if you strictly adhere to the heating regime of the parts and the minimum number of parts connected using the butt method.

Methods for connecting PP pipes

In order to install the system correctly, it is necessary to accurately follow the installation technology of PP pipes. The intended purpose of the project determines the sequence of assembly of the system and how to properly weld (cook) a polypropylene pipe.

• coupling connection - in this case, the end part of the PP pipe is spliced ​​with the continuing outlet using a fitting in the form of a coupling. In this case, the technology most often used for welding polypropylene pipes is when the outer surfaces of the polypropylene pipes and the inner surfaces of the coupling are heated, the so-called “socket” welding. The result is a strong, reliable and hermetically sealed connection, subject to all welding stages and heating temperatures. The method of socket welding of polypropylene pipes is the most common;
• butt connection. The surfaces to be welded are the end sections of the leading branch and the mating part of the polypropylene pipeline. Butt welding is most often used when laying large diameter pipes (40mm and above).
• The technology for welding large-diameter polypropylene pipes involves the use of special, professional equipment. The connection is highly durable. If the temperature and clamping force are chosen correctly, the connection is sealed;
• connection using clamping or self-locking fittings. It is rational to use for main pipelines with low pressure levels;
• cold welding of polypropylene pipe.

The use of adhesives and quickly hardening components with high adhesion to create durable and airtight seams.

Small diameter pipes are most easily connected using fittings

Cold welding allows you to solve the problem of how to weld a polypropylene pipe for heating in places where it is not possible to use electrical equipment.

Important! The quality of joints depends no less on the class of welding equipment than on the qualifications of the installer. Pipes must be prepared for welding. The presence of dirt, water, organic substances and poor-quality cutting, welding of PP pipes at a temperature lower than the plastic melt leads to weak seams, and as a result, the tightness of the joints is out of the question.

Manual welding technology for polypropylene pipes

In order to weld PP pipes, you need to stock up on the necessary equipment and components. First of all, a detailed project is drawn up, an assembly option is determined, and a decision is made on how to weld a polypropylene pipe with fittings and a mating part of the pipeline. Based on the configuration and geometric shape of the future pipeline, the welding for the polypropylene pipe is determined, which is better suited for a specific project and will not entail an increase in the construction cost. The number of rotary fittings, branch tees and couplings and the installation procedure are calculated, which is also the procedure for welding polypropylene pipes.

During installation, it is possible to adjust the pipe routing, but due to the ease of connection this does not cause any particular problems.

Manual welding of polypropylene pipes does not require a large supply of tools or special skills. Precise adherence to the assembly sequence makes it possible to create a reliable plumbing or heating system that is sealed along its entire length.

Manual welding of pipes is carried out using a compact heating device

Tools and equipment:

• scissors or plastic pipe cutter. Preferable are guillotine-type scissors, with a powerful blade and a toothed force transmission unit;
• tool for stripping reinforced PP pipes. It is a special cutter, and in its primitive form a durable knife with a comfortable handle and a short blade;
• To degrease the surface, it is advisable to use alcohol components. As a rule, ethyl (isobutyl) alcohol is used. Acetone, which is very common as a degreaser for paints and varnishes, is not suitable for PP pipes - it simply destroys the surface, making it loose and fragile;
• A soldering iron for polypropylene pipes is a surface heated to a selected temperature (at least 260 degrees Celsius) - a mandrel - on which nozzles for pipes and fittings are attached. Soldering irons come in tube-shaped and elongated hammer shapes. It is more convenient to weld pipes in hard-to-reach places with a pipe-shaped soldering iron;
• A regular construction tape will help avoid waste of materials. Correctly measured length of the section will minimize the number of cuts and adjustments;
• template in the form of a short piece of pipe of larger diameter. The length of the template must exactly match the depth of insertion of the pipe into the fitting. It is better and more convenient to use a template with a bottom. Butt welding does not require the use of templates.

If the technology for welding a polypropylene pipe for heating is correctly followed, then after the weld has cooled, an even, neat bead is formed, the same in height along its entire length.

Important! Excess molten plastic inside the parts being welded will lead to a reduction in the internal cross-section of the pipeline. This leads to an unplanned increase in pressure, and impairs the permeability of water or coolant inside the heating system. The more careful the approach to soldering, the better the quality of the welds.

Installation steps and soldering features

Strict adherence to all stages of pipeline creation is necessary; this is the only way to obtain a reliable system.

The procedure is as follows:

1. PP pipes are being prepared for work. A thorough inspection of the outside will allow you to identify, even before the assembly stage, those pipes that may have manufacturing defects. This is especially important for pipes from which a hidden heating system is installed. The heating temperature of the pipes is determined.
2. The surface for installation is prepared. A preliminary calculation of the attachment points of the PP pipeline distribution branches is carried out, and problem areas of the future system are determined: the intersection of walls and ceilings, the procedure for connecting to existing ones engineering communications. Welding a polypropylene pipe directly with your own hands is not difficult, although sometimes you have to weld the elements of the system one by one.
3. Tools are being prepared. The trimming blade must be sharpened in such a way as to create an even, perpendicular cut without changing the geometry of the pipes.
4. The nozzles of the pipe iron (soldering iron) must be clean, free of traces of melted plastic and other contaminants. Clean the soldering iron nozzles during heating using a cotton cloth or a wood chip. The manufacturer informs the buyer about how to properly weld a polypropylene pipe of each specific type - the instructions for the soldering equipment indicate the temperature level and warm-up time.
5. The nozzles are installed on the soldering iron, heated to the melting temperature of the polypropylene pipe, welding occurs due to the softening of the outer layer of the pipes or the inner surface of the fitting. Installation is carried out correctly if the heating temperature of the components corresponds to the cross-section of the pipe and fitting.

A high-quality tool has heat adjustment and a stable stand. Welding pipes with such a soldering iron is convenient and safe if a minimum of care is taken.

Long-distance industrial pipelines, technological systems, and heating systems that use large-diameter pipes are usually connected to each other using special equipment necessary for uniform heating of the connected sections. This is exactly how polypropylene pipes are welded; the heating temperature is controlled automatically by the machine.

A special machine is used for butt welding of large diameter pipes

It is customary to weld a pipeline line end-to-end, and in the presence of a mechanical welding complex, the connection is very strong.

Components of a stationary automatic welding complex:

• a supporting frame on which all components are mounted;
• mechanical saw for cutting pipes;
• automatic grippers for pp pipes;
• internal self-leveling liners for reliable fixation of pipes;
• electronic temperature control unit;
• a heating element.

How to weld a polypropylene pipe using a welding machine

The sequence of actions when working with a mechanical welding machine is slightly different from working with a hand soldering iron. The technology for welding polypropylene pipes in automatic mode is similar to manual soldering, with the exception that the stripping (trimming) of the pipe occurs using a mechanical saw, and the clamping of the pipes at the soldering site is provided by mechanical grips. The process is called butt welding of polypropylene pipes.

Control of the heating temperature level when welding polypropylene pipes and automatic shutdown of the heating element is provided by the control system unit.

Butt welding of a polypropylene pipe using an automatic unit takes a minimum of time and is characterized by high quality seam joints. The precise welding temperature of polypropylene pipe is another advantage of the automatic system. This is important for heating systems, but the cost of professional equipment is quite high. But this problem can be solved simply: you can rent the necessary devices.

Welding of polypropylene pipes

Polypropylene pipe welding technology

Soldering of polypropylene pipes is carried out using special devices that provide precise control over the time and temperature of melting of parts. For cold water systems, the use of cold (glue) welding is allowed.

How to choose a device?

According to their shape, all devices for welding polypropylene pipes are divided into:

• Sword-shaped (“irons”): inexpensive devices designed for welding pipes with a diameter of up to 40 mm, with a heating element in the form of a plate into the holes of which paired nozzles are inserted - replaceable couplings and mandrels. The Teflon coating prevents the plastic from sticking to the metal. They are used mainly for periodic or one-time work. If you have chosen just such a device, in addition to its power and thermoregulation methods, it is necessary to check the stability of the structure.
• Cylindrical: semi-professional and professional units, the heating element in which has the shape of a straight or side cylinder. The L-shaped welding machine with a side cylinder can be used for soldering in hard-to-reach places.

The speed of operations directly depends on the power of the device. For one-time work, it is better to purchase a medium-power tool. You should focus on the diameter of the pipes. For example, if it is 40 mm, this figure is multiplied by 10, plus 20-40% of the margin is added. That is, 40 x 10 + 80 = 480 W. We round the figure to 500 W. For larger diameter pipes (for example, 16 cm), you will need a professional, expensive unit with a power of 1800-2000 W.

The heating level, information about which is displayed on the display, is set by the thermostat. Devices with electronic or microprocessor thermostats are considered more accurate, allowing the temperature to be measured as accurately as possible. In capillary and bimetallic thermostats, the measurement error increases.

You don’t need too many attachments for a hair dryer used in everyday life - it is enough to purchase a device with attachments with diameters of 20, 25 and 32 mm. Moreover, it is problematic to weld pipes with a diameter of more than 40-60 mm using hand tools. The soldering iron kit may include additional tools: a chamfer, a cutter, a shaver for stripping reinforced plastic, a calibration device, a trimmer, etc. You can also purchase them separately.

Process technology

Depending on the type of connection, welding of polypropylene pipes can be carried out:

• Socket: in a similar way, pipes of small diameter (up to 40 mm) are connected in heating and water supply systems. Centering and compression are ensured by the calculated dimensions of the pipe and coupling or other shaped product (tee, adapter, etc.). In the normal state, the diameter of the pipe is slightly larger than the internal diameter of the coupling; after they are melted and a little physical force is applied, the pipe enters the coupling to a depth equal to the heating depth, forming a strong and reliable fastening. A certain time is allowed for polymerization.
• Butt: for connecting parts of the same type and equal diameter. The ends of the pipes are located on the same axis, that is, end to end. As a result of simultaneous heating and mechanical compression of the parts, polypropylene interpenetrates. To achieve this effect, the use of special machines is required. The method is not used in domestic conditions; it is used for welding thick-walled large-diameter pipes in highways.

Pipes with a diameter of 4 cm or more are very difficult to connect and center manually. For such work, electrofusion units with alignment devices are used. Such devices operate automatically and are high-tech, expensive equipment.

What heating temperature is needed?

To obtain a strong connection, it is important to determine the exact heating temperature. If it deviates in one direction or another, there is a risk of damage to the plastic during operation and leaks. At low temperatures, the plastic will not melt enough, and the fastening will be fragile. If there is an excess of it, it will be excessively deformed, and due to the formation of sagging, the diameter of the hole will decrease. Yes, and inserting an overheated and too softened pipe into the fitting will be problematic.

The temperature of the heating element is set by a mechanical (bimetallic) or electronic thermostat. If working with polyethylene requires a temperature within 220°C (±5), then polypropylene is welded at a higher temperature of 260°C. Experts advise that when purchasing a welding machine, immediately set the desired temperature and do not change it in the future. On old “soldering irons” it is not adjustable at all, but such devices are quite suitable for use.

The heating time of the pipes depends on their diameter. It must be followed exactly:

• 20 mm: heating takes no more than 6 seconds;
• 25 mm: 7 seconds are enough for soldering;
• 32 mm: processing time 8 seconds;
• 40 mm: heat up 12 seconds.

Modern machines for welding polypropylene are equipped with a light or sound warning system. You just need to set the desired temperature and time.

You should also pay attention to the ambient temperature. In cold rooms, the heating time of the soldering iron is increased by 2-3 seconds. Although it is better to select this time experimentally. At air temperatures below +5°C, the heating time increases by 50%.

Despite the apparent simplicity - heated, connected, cooled - there are many points in welding polypropylene that should not be missed:

• If you have a complete lack of experience, it is better to first practice on a piece of pipe, because heated polypropylene does not retain its plasticity for long, during which time you need to have time to connect the elements without distortions, fix them firmly and, without changing their position in any way, wait until they cool completely.
• Pipes and fittings from different companies, even of the same diameter, should not be welded together - due to the difference in chemical composition, it will be impossible to achieve a reliable connection.
• To obtain an even cut at exactly 90°, use only a very sharp tool. All burrs are carefully cleaned.
• You need to buy only high-quality plastic - if you choose products from a dubious manufacturer, the pipeline may leak.
• It is prohibited to work in weight; the welding iron must have a stand. It is more convenient if it is attached to the table in the form of a screw clamp.
• Since the fitting takes a little longer to warm up, it is put on the nozzle first.
• You should not hesitate too much and delay the interval between heating and installation - the welding will be fragile.
• The pipe must be inserted into the fitting all the way, otherwise it will leak over time in the place where the gap is formed due to a decrease in the wall thickness.
• Plastic melts formed during the welding process should not be removed immediately - an uncooled joint is easily deformed. Although, of course, experienced craftsman splashes appear very rarely.
• Rotating or screwing in parts when connecting is prohibited; movement must be done only in a straight line.
• Excessive force during connection is also unacceptable - as a result, a large influx of plastic may form in the pipe, preventing the passage of liquid.
• An accidentally damaged fitting should be replaced with a new one; soldering it end-to-end with a pipe is unacceptable.
• Some Chinese and Turkish-made units are equipped with two heating elements with separate switches. But to avoid the risk of polypropylene overheating, you should not use both at once; let the second heater be only a spare.
• The cooling time should be approximately equal to the heating time. You should not shorten this period, otherwise the connection will be fragile.
• The pipe joints should not be dirty - welding dusty and dirty products can lead to loss of strength. Additionally, the surfaces to be welded are degreased with acetone, gasoline or white alcohol. It is prohibited to use ordinary vodka for these purposes, as it can loosen plastic.
• Ingress of moisture is also unacceptable. If water accumulates in the pipes, they are filled with salt or bread crumb; to remove them after welding, they should be rinsed well.
• For hot water systems, polypropylene reinforced with foil or fiberglass is used. When stripping the foil, even a small remaining piece is enough to cause a leak to form during operation; it must be carefully removed along the entire length of the solder. Stripping the fiberglass is not required - this material solders very well.
• Not only the cleanliness of the pipes, but also the soldering iron itself is important. After each operation, any remaining plastic must be completely removed.

Cold welding

Joining polypropylene using a special glue (cold welding) is no less strong than fixing it using the hot welding method. However, it is used only for pipes supplying cold water. After all, glue can soften under the influence of high temperatures.

The installation process is simple:

1. The pipes are cut exactly at an angle of 90° and cleaned of burrs, dust and dirt.
2. Markings are applied to fittings and pipes in such a way that when they are connected, there is no gap of more than 1 mm between the fitting stop and the pipe.
3. The glue is spread in a thin layer onto each of the parts.
4. They are fastened together.
5. The connection is fixed by hand in a stationary position for 15 seconds.
6. You can connect the water an hour after cold welding.

Do-it-yourself welding of polypropylene pipes for beginners: video, instructions on which welding machine to choose

Welding polypropylene is one of the ways to connect water and sewer lines. In this case, hermetic joints are obtained, since the products are cross-linked at the molecular level. If the soldering of polypropylene pipes is done correctly, the service life of the water supply or drainage system increases many times over.

Specifics of soldering polypropylene pipes

Welding of polymer products is carried out using technology, which is realized through the use of material properties. Polypropylene is flexible. However, PP products acquire this property when the temperature changes. Its increase to a certain level helps to soften the material.

Cooling of a heated pipe joint also occurs quickly. For this reason, soldering/adhering time is reduced. If you perform actions to connect communications slowly, the quality of the connection decreases. In this case, it is difficult to ensure the tightness of the seam.

Welding of polypropylene pipes is possible due to the properties of this material. Melting point - from +149°C. Soldering irons are used for soldering polypropylene. They provide heating of PP products to a level of +320°C, but at home a less intensive operating mode is used (up to +300°C).

PP pipes must not be exposed to a heat source heated to critical temperatures. It is also not recommended to use a soldering iron on the pipe for too long. Under such conditions, the material loses its properties, and the product will become wrinkled as a result.

General description of technology

There are 2 methods of recording communications:

• coupling;
• butt.

The first technology for welding polypropylene pipes with your own hands is more suitable for beginners, because it requires less skill. The work can be completed even if the pipeline has not been installed in this way before.

The coupling method is based on the need to use special connecting elements that completely encircle the end part of the communications. Inside the coupling there is a connecting seam of 2 products. For domestic water supply this installation method is more suitable.

If it is not possible to use a shaped part, you can make a semblance of it. To do this, use a straight section of communications and trim it. Take into account that products are inserted into the fitting from 2 sides to a certain depth. The coupling method is used for joining communications with a diameter of up to 63 mm.

The direct fixation method requires heating only the end sections of the pipes. In this case, a fitting is not used, the seam connection is not closed with anything. This technology is used for welding large-diameter polypropylene pipes; it is rarely used in everyday life.

The disadvantage of this option is the difficulty of correctly positioning communications in accordance with the axis. Even small deviations to the sides can slow down the flow of fluid through the pipeline. For direct installation, a centering system is additionally used.

Tool for installing polypropylene pipes

Photo of the instrument	Name
	welding machine, for work at home it is recommended to use units designed for welding PP pipes of small and medium diameter - up to 63 mm.
	The pipe cutter is an ideal device for cutting polypropylene.
	Shaver - designed to remove a layer of reinforcement.
	A trimmer is needed for high-quality pipe joining
	Marker for marking pipes.
	Using a building level and a pencil, draw the direction of the pipes on the wall
	A tape measure is one of the main tools in construction.
	A degreaser is needed to remove impurities from the surfaces of welding joints.

A soldering iron can be purchased or rented. You don’t always have a trimmer or shaver at hand. However, these tools will be needed to work with reinforced pipes. So, the shaver is designed to remove reinforcement. Its knives are located parallel to the axis of the pipe. Thanks to this, the middle layer of communications is removed. The trimmer is used to prepare pipes and remove the reinforcement layer. Such a tool processes the end; in addition, it creates a chamfer.

When studying information on how to properly solder polypropylene pipes, you need to take into account what is first compiled in an apartment or private house. This must be done to calculate the amount of materials and determine the exact length of communications.

A marker and tape measure are used to mark. Moreover, it is necessary to determine not only the places for cutting products, but also the areas that will be inserted into the nozzles of the welding machine

Soldering machines for pipe welding

Such devices are designed quite simply. Main nodes:

• temperature regulation and control unit;
• handle for fixing the device;
• support to avoid direct contact between the surface on which the welding machine is installed and the heating element.

The kit includes nozzles that differ in diameter, as well as gloves and small tools. The equipment varies depending on the model of the device. The wider it is, the higher the price.

Types of soldering irons for polypropylene

There are manual and mechanical soldering irons. However, in everyday conditions the first option is used. This is due to the simplicity of the design, ease of operation, and small dimensions.

Do-it-yourself soldering of polypropylene pipes is done using 2 types of devices:

• sword-shaped soldering iron;
• cylindrical.

Soldering irons differ in the shape of the heating element. The xiphoid device plate has several holes, which allows for installation various attachments, which consist of 2 parts: mandrel and sleeve. They are designed to heat the end sections of communications. So, a connecting element is mounted on the mandrel; the sleeve is designed to heat the end section of the pipe.

Heating of products using nozzles must be carried out simultaneously. When studying the question of how to weld polypropylene pipes, it is necessary to use devices that include Teflon-coated nozzles. This prevents the molten material from sticking to the metal.

Cylindrical devices differ in design from sword-shaped ones, which is due to the presence of a heating element in the shape of a cylinder. In this case, crimp-type nozzles are used. They are put on a metal cylinder and firmly fixed. On both sides of such nozzles there is a mandrel and a sleeve. The soldering principle is the same as in the case of the sword-shaped analogue.

Criteria for selecting welding machines

1. Power. To work with communications with a diameter of no more than 75 mm, you should purchase a device with a power of up to 1000 W. Its capabilities are sufficient to ensure high quality seams. However, in everyday life, the soldering method is more often used to fix pipes with a diameter of up to 50 mm. In this case, units with a power of up to 700 W can be used. Moreover, you need to remember that the starting currents when turned on are much higher, so a power reserve (20-30%) must be provided.
2. Type of heating element: plate, cylinder. In everyday life they use the first option; it is easier to work with. This is important if you have no experience in installation work of this type.
3. Number, type and size of nozzles. Determine which products need to be soldered. The diameter of communications is taken into account. In the most simple models it is possible to simultaneously solder 2-3 pipes and even more, the same number of fittings. In this case, the heating element has 2-3 holes.
4. Manufacturer.

On the construction market you can find production equipment different countries: Russia, China, Turkey, Czech Republic. The latter option is more expensive; such devices are distinguished by high build quality and reliability. Welding machines may have errors when measuring temperature. As a result, the actual indicator often does not correspond to the target one.

Czech technology wins according to this criterion; the error of such soldering irons is minimal. However, in everyday life, beginners should use Russian or Chinese models, since they are cheaper, although they have a significant error, which for some models is 10°.

How to properly solder polypropylene - instructions

You need to act consistently, in this case the likelihood that a mistake will be made is reduced.

1. Preparing the room. Considering that toxic substances are released during soldering, effective air circulation should be ensured.
2. After cutting, the edges of the communications are processed with a trimmer or chamfer. They make chamfers, this makes it easier to join the pipes.
3. The materials are degreased: cleaned of dust, treated with white spirit. You need to continue working when the surface is completely dry.
4. Turn on the soldering iron, having previously set the temperature to the required level (+260°C).
5. When the green light on the body of the soldering iron lights up, you can proceed to soldering. A pipe is installed in the sleeve nozzle, and a fitting is placed on the mandrel.
6. At the same time, 2 elements of the future pipeline are heated: a fitting, a pipe.
7. After waiting the time indicated in the table above, the pipe and the shaped element are removed from the nozzles and joined to each other. In this case, the parts must be held motionless. Communications are connected to a previously drawn longitudinal line. The slightest displacement of polypropylene that has not yet hardened will lead to the destruction of molecular bonds. This may cause a leak in the future.

Soldering table for polypropylene pipes

The heating and holding time of PP pipes at a given soldering iron temperature allows us to ensure high quality seam joints. Low heating will not allow softening of communications. In this case, it will be impossible to join the pipes.

Connecting pipes by soldering with reinforcement

The operating temperature of communications for cold water supply varies within -10…+90°C. Under the influence of the coolant, the pipeline bends, as intense linear expansion occurs. This means that for heating you need to use pipes that have more suitable characteristics.

Thus, in conditions of exposure to high temperatures, products reinforced with fiberglass or aluminum are used. Such pipes are multilayer products: a thin layer of fiberglass is applied on top of the polymer product and covered with a layer of PP. Advantages:

• relative stability of linear expansion, even under the influence of high temperatures the geometry of the product changes slightly;
• ability to withstand pressure up to 10 atm, for comparison, in apartment buildings communications are subject to less intense influence (6-8 atm);
• due to the presence of a reinforcement layer, the service life of the pipeline increases;
• pipes with internal reinforcement exhibit resistance to high temperatures, at which classic version communications begins to melt.

The technology for soldering reinforced pipes does not differ from the method of joining unreinforced communications, with the only exception: at the preparatory stage, the ends of the products must be cleaned of the reinforcing layer, for which a trimmer or shaver is used. After preparation, the pipes are degreased, then heated with a soldering iron and connected.

Rules for soldering PCB to avoid mistakes

• The diameter of the polypropylene pipe is selected;
• before work, prepare everything necessary, since welding is performed quickly, there will be no time for preparation during the installation process, the soldering iron is turned on when the communications are already cut;
• the welding machine must be securely fixed on a horizontal surface, the quality of the seam will depend on this, such units are equipped with special stands, but some models are not installed firmly, so they need to be additionally secured;
• the melting temperature of polypropylene is much lower than the value set in the welding machine settings, this difference is due to the need to quickly soften the pipe; a temperature of +260°C is considered sufficient;
• You should not change the temperature regime when using larger products, when soldering PP pipes, the heating temperature does not change with an increase in the diameter of the communications, from the table above you can find out that the dimensions of the products only determine the duration of heating of the material;
• you need to navigate by the indication: a red light indicates that the heating element has turned on, a green light indicates that the set temperature value has been reached;
• often users skip the stage of degreasing the material, however, the presence of dust or drops of water in the cut area can cause the seam to weaken, since in this case the structure of the material becomes more porous;
• when installing a pipeline of complex configuration, it is necessary to connect the pipes at different angles, they are also rotated relative to each other; in order not to disturb the alignment of the products, it is recommended to first determine the exact position of the communications, then perform their preliminary installation (without using a soldering iron), at this stage you need to draw a marking strip along the center line through the 2 parts to be connected.

It should be taken into account that thin-walled pipes warm up faster. This means that the period of operation of the soldering iron is reduced by 2 times. If you are studying the question at what temperature to solder such pipes, you need to remember that the value of this parameter does not depend on the dimensions of the product. Thin-walled communications are connected to each other at the same temperature conditions, as thick-walled.

Impact of errors on welding quality

The most common violations of the soldering process:

• surfaces are not degreased, resulting in a decrease in the quality of the seam joint;
• The cut angle of the pipe and fitting does not correspond to 90°;
• insufficient deepening of the pipe into the fitting or, conversely, communications are brought into the shaped element all the way, as a result, a large seam is formed inside, which impedes the flow of liquid;
• violation of the heating technology: the pipes were on the nozzles for too little or, conversely, a lot of time, in both cases the quality of the seam joint will be low;
• when connecting reinforced pipes, the reinforcement layer at the end section was not completely removed, as a result, this material will prevent the melting of polypropylene, such a seam will be weak, or it will not be possible to make it at all;
• after joining, the position of the parts was adjusted, which led to a decrease in the reliability of the seam; To avoid such consequences, you should wait a while after connecting the pipe and fitting, ensuring that the parts remain stationary.
Method with gas burner less preferable.

If a torch is used, it will not be possible to heat the polypropylene evenly. As a result, the seam joint will look sloppy, in which case the reliability of the seam is reduced. Over time, a leak may appear in this area. This method can be used as a last resort and only when installing cold water supply systems.


Connecting a pp pipe with a compression coupling

The compression coupling provides a reliable connection of communications and is used as a complete replacement for a welding machine. However, the cost of such an element is high. As a result, costs will increase, since a large number of compression fittings will be needed to distribute pipes throughout the room.


Method for gluing polypropylene pipes.

The cold welding method is also effective. In this case, a two-component epoxy composition is used. This material allows you to obtain a reliable connection without special equipment.

To fix the communications, you need to apply an adhesive substance to the cleaned and degreased surfaces of the products. Then the pipe and fitting are joined, holding tightly. The glue sets within 10 minutes. It takes 1 hour to completely harden. This option can only be used when installing a cold water supply system.

Conclusion and useful video about soldering polypropylene

When soldering polypropylene communications, you need to properly prepare the material (mark it, cut it), and tools. Work is performed sequentially. For example, if you skip the degreasing step, the seam will not be reliable enough.

Video instructions for soldering polypropylene pipes:

It is important to follow the rules for heating and joining pipes, otherwise, after putting the pipeline into operation, it may be necessary to repair it. You can learn about the intricacies of soldering from the video.