How to solder pvc pipes. Soldering plastic pipes - devices and tools for connection

03.03.2020

Recently, traditional cast iron and steel pipelines are increasingly being replaced by more modern products. chemical industry- PVC and polypropylene pipes. But new materials require a different technology for connecting pipes, and brazing is the most effective in this case.

Note! The soldering temperature, which affects the quality of the connection, depends on the dimensions of the products - this can be seen in the table below.

Polypropylene pipes, marking	Characteristics and purpose
PN 10	technical characteristics are acceptable for cold water supply up to 20 degrees Celsius, floors warm system up to 45 degrees, at working pressure - 1 MPa
PN 16	characteristics determine the use for both hot (up to 60 degrees Celsius) and cold water supply, nominal working pressure - 1.6 MPa
PN 20	technical characteristics of this type of pipes allow the use in hot water systems with temperatures up to 95 degrees, nominal pressure - 2 MPa
PN 25	reinforced polypropylene pipe: characteristics are suitable for hot water supply, as well as for central heating systems up to 95 degrees Celsius, nominal pressure - 2.5 MPa

Step 1. Choosing one or the other source material directly depends on the future destination. The main criterion for division is the maximum allowable temperature of the working medium. In this regard, pipes are distinguished for hot, cold, as well as mixed water supply.

To determine the exact number of pipes and fittings needed, the room is measured and compiled. rough plan. The latter indicates the dimensions of the future highway and all its elements.

After purchasing all the components, you can proceed to the next step.

Stage 2. Necessary equipment

The principle of soldering is to heat the ends of the pipes to be connected to the required temperature and then fix them. To do this, you need a special device - a welding machine.

It can be of three types:

In addition to the device itself, the work will require:

About the choice of nozzles

The heating nozzles must correspond to the cross-section of the connected pipes. To do this, you need to pay attention to certain parameters:

strength;
shape retention during temperature changes;
thermal conductivity.

Most welding machines are compatible with several different nozzles at once, which is extremely convenient when arranging complex highways.

Each nozzle has two ends at once - one is intended for heating the outer surface of the products, the other for the inner one. All nozzles are coated with Teflon, which prevents sticking of the molten coating. The dimensions of the nozzles vary between 2 cm and 6 cm, which completely coincides with the common and pipe sections.

When the plan is drawn up, and all the components are purchased, it remains only to carefully clean the room. Particular attention should be paid to dust, because even the smallest particles, settling on the seams, can easily break the tightness.

First, the nozzle is inserted into the socket, after which the device is turned on. Further actions depend on the chosen soldering technique, so we will consider them (methods) in more detail.

Method number 1. Diffusion soldering

When using this welding technology, the material of the parts to be joined mutually penetrates each other, and after cooling it forms a monolithic element. One of the most common processing methods, which, however, is only suitable for homogeneous materials.

Note! In this case, the soldering temperature reaches 265ᵒС. It is at this temperature that polypropylene melts.

Video - Diffusion brazing of PP pipes

Method number 2. Socket soldering

When welding in a socket way, welding machines with different nozzle cross-sections are used. The procedure itself looks quite simple.

Step 1. First, pipe sections of the required length are cut. It is important that the cutting takes place exclusively at right angles.

Step 2. The ends of the products are cleaned with a shaver (if reinforced pipes are used).

Step 3. The ends are inserted into the nozzle of the appropriate section, heated to the melting temperature and connected.

Note! It is extremely important that the pipes do not change their position when cooling.

Method number 3. Butt soldering

This method suitable for connecting pipes large diameter. As in the previous versions, the pipes are cut into sections of the required length, and the ends are carefully cleaned.

Method number 3. Sleeve soldering

With the coupling method of welding, an additional part is introduced between the elements to be connected - a coupling. Warming up occurs in the same way, only the sections of the highway are not heated, but only the connection elements.

Method number 4. Polyfusion soldering

A kind of diffuse technology, characterized in that only one of the two connected elements is melted.

Method number 5. "Cold" soldering of PP pipes

This welding method involves applying a special adhesive to the pipes to be joined. It is characteristic that the use of "cold" welding is permissible only in those lines in which the pressure of the working fluid is negligible.

When overheating or connecting pipes of small diameter, there is a risk of formation of sagging on inner surface. These influxes will prevent the free movement of the working fluid during operation.

To avoid this, it is necessary to check the connection for such defective areas. The junction must be blown through, and if the air passes unhindered, then the welding definitely turned out to be of very high quality.

Note! After that, it is necessary to check the tightness of the connection - for this, a small amount of water is passed through the soldered elements.

Important Rules for Soldering Polypropylene

For a high-quality and tight connection, certain rules must be followed.

Soldering PP pipes in difficult areas

To the question what the main problem when arranging a plastic pipeline, any specialist will answer: soldering in hard-to-reach places. To perform this procedure, the structure is divided into several sections.

First of all, an uncomfortable large area is mounted. It is advisable to form it separately, and only then install it in a stationary place.

After fixing the problem area, smaller and, accordingly, easy-to-install elements are installed. This activity should be done by at least two people.

Video - Installation in hard-to-reach places

Typical mistakes when soldering plastic pipes

Video - Technology for soldering PP pipes

Results

Skills in soldering PP pipes will come with time. There is nothing complicated here, although at first several couplings and one or two dozen meters of pipes will be damaged. And this is not scary, because they are not so expensive; at least autonomy from plumbers is more expensive.

Polyethylene pipes, produced mainly from HDPE (low pressure polyethylene), occupy a strong place in many areas of industry, construction and everyday life due to the presence of many technologically advantageous characteristics. This necessitates the need for optimal methods of their connection, without which the process of installation and arrangement of pipeline lines is impossible.

Varieties of polyethylene (PE) pipe connections

Among the various types of connections between polyethylene pipes, detachable and one-piece connections are distinguished.

The detachable method allows disassembling the assembled structure at the end of operation. Accordingly, it is optimal in cases where there is no need for its long-term use. A similar connection of pipes is carried out by means of steel flanges.

More durable and more often used in practice is a one-piece connection. It is carried out by welding or soldering PE pipes, which, in turn, can be butt or coupling. Both methods are effective and reliable, allowing you to get monolithic strong connections.

Butt welding of polyethylene pipes

Butt welding of polyethylene pipes requires special welding equipment. This connection method is effective for soldering HDPE pipes only. Its versatility lies in the fact that it allows you to maintain the flexibility of the structure throughout its entire length. be used this method can both with trench and with open method pipe laying.

Butt welding of HDPE pipes is carried out in the following sequence:

Installation of the ends of the products to be welded in the centralizer of the welding equipment.
Alignment and tight fixation of parts.
Cleaning the end sections from dirt, dust, grease, other blockages and layers (carried out by means of a cotton cloth soaked in alcohol).
Processing of end fragments by means of a trimming device (trimming). The process is carried out until a uniform chip appears, not exceeding 0.5 millimeters in thickness.
Removing workpieces and checking the ends by hand for parallelism. If a significant gap between the surfaces is detected, the trimming is repeated until the necessary compliance is obtained.
Heating of the ends of billet pipes with a heating element, the surface of which is covered with a non-stick layer.
Upon reaching some melting of the workpieces, the heating element is removed and the ends of the welded pipes are closed. The clamping pressure is increased until a complete and firm closure is achieved. Products should be kept for some time (usually 5-10 minutes) until the joint is completely hardened.
Checking the quality of the welded structure. Estimated appearance weld ends, their correspondence with each other and soldering strength.

In addition to the welding process itself, it is important to pay increased attention preliminary work listed in the opening paragraphs. They should be carefully performed before soldering HDPE pipes, since the reliability and strength of the connection being made largely depends on this.

A prerequisite for high efficiency butt welding is its implementation by means of a single seam. Only in this case is the maximum strength of the welded joint achieved, otherwise it may be insufficient.

Socket welding of HDPE pipes

The sleeve method of soldering polyethylene pipes is carried out by means of a special device called a soldering iron, and a set of special nozzles desired diameter. In the welding process, fitting products are used: couplings, tees or corners. The ends of the workpieces to be joined are welded to the fittings, which serve as connecting elements.

If you have the necessary soldering unit, you can solder HDPE pipes with your own hands. This work is not very difficult and within the power of any home master.

Before you solder the HDPE pipe with your own hands, you should do some preliminary work, in particular:

Cut the blanks with special scissors to the right sizes. The cuts must be strictly perpendicular to the longitudinal axis of the workpieces.
Clean the end sections of the products to be joined.
Close the ends of those pipes that are not currently being welded with stoppers to avoid contamination and cooling.
Clean the heated surfaces of the soldering unit from clogging and particles that may have remained from previous work.

Heating the nozzle parts of the soldering iron to the required temperature. When the heating reaches the required values, the indicator on the body of the device gives a special signal.
The HDPE pipe is inserted all the way into the sleeve, and the fitting is also pushed onto the mandrel all the way. This action may require some effort.
As the pipe is inserted and the fitting is pushed onto it, excess molten material is squeezed out from the surface of the product. As a result, a kind of annular bead, called a flash, is formed in the area of the welded edge.
The parts to be connected are removed from the nozzle, after which the pipe is inserted into the fitting so that it is in close contact with the annular bead. See also: "".
They wait for the welded pipes to cool down without exposing them to any external influences.

Due to the fact that it is difficult to determine the exact depth of immersion of the pipe during the welding process, it should be measured in advance and an appropriate mark should be made on the surface of the product.

Electrofusion welding

A special type of socket welded joints of PE pipes is the electrofusion method, which makes it possible to obtain high-strength structures. For its implementation, it is necessary to use a special electric coupling for HDPE, equipped with embedded heating elements. The welding process is also carried out using welded HDPE fittings equipped with heating coils. Due to the heating and partial melting of the fitting material, a connection with polymer pipe and the formation of a monolithic structure.

The elements and parts used in this method are quite expensive, however, the advantages of electrofusion welding are the absence of flash formation, which reduces the patency of pipes, and the ability to weld parts in confined space where installation of overall welding equipment is impossible.

Electrofusion welding between PE pipes is carried out in the following sequence:

The pipes are cut into the required lengths by means of special cutting tools.
The parts to be welded and the electric coupling itself are cleaned of dust, dirt and grease.
Marks are made on the pipes to control the depth of insertion into the coupling.
Those pipe ends that are not currently being welded are plugged to prevent unwanted cooling.
The electric coupling is connected to the welding device by means of wires.
The welding process is started using the start button of the device.
At the end of the welding process, the machine switches off automatically.
Wait at least one hour for the hardening and complete readiness of the welded joint, after which it becomes serviceable.

An important condition for obtaining a high-quality welded joint is the preservation of the immobility of the parts during the soldering process and subsequent cooling. One of the indicators of the quality of the weld is the thickness of the bead, which should be from one third to half the thickness of the pipe itself. The roller should overlap the mark previously made on the pipe. The displacement of pipe sections to be welded relative to each other should not exceed 10 percent of their wall thickness.

Choosing a method for soldering HDPE pipes

Not each of the listed options may be well suited for connecting HDPE pipes in certain conditions. Various ways have their advantages and disadvantages, and along with this there are a number of factors on which the answer to the question of how to solder also depends polyethylene pipes in any particular situation.

The coupling method is optimal in cases where it is necessary to solder in hard-to-reach places. Since in such a situation the axial displacement of the products relative to each other is difficult, butt welding becomes impossible, and the only acceptable method is a socket connection.

In the most inaccessible areas, with a severely limited space for work, HDPE pipes are soldered using an electrofusion method. Another significant advantage of this method is its speed, which is also sometimes important.

Finally, in those cases where there is a need for a one-time pipe connection to perform one or another short-term job, soldering is not required at all, and a temporary detachable connection can be dispensed with.

How to solder polypropylene (plastic) pipes

So, dear reader, you have decided to change water pipes in the apartment with your own hands. And if your choice fell on polypropylene pipes I will help you learn how to work with them correctly.

I won't go into too much technical description polypropylene pipes, a separate article will be written for this, and I will immediately proceed to the briefing.

tool for soldering polypropylene pipes

From the tool we need:

Alcohol marker (a marker for discs will do)
Roulette
Building level
Special pipe cutters
Soldering iron for polypropylene pipes

The last one from the list will be cheaper to rent, I don’t see the point in buying such a home, because. it will only be needed once. You can rent it in the same place where you buy plastic pipes.

This list is only required for soldering pipes. If you are going to lay pipes in a strobe, it will be useful to read the article, in which I described the wall chasing technology.

Instructions for working with a soldering iron for polypropylene pipes

Soldering iron, he is a welding machine for plastic pipes has a sole with heating elements inside and special holes for attaching nozzles for soldering pipes of different diameters. Nozzles, as a rule, come with a soldering iron. The principle of operation of the soldering iron is almost the same as that of a home iron, except that in a home iron there is one heating element, and in a soldering iron for pipes there are two and each has its own switch on the body of the soldering iron. On the body, in addition to the heater switches, there is also a thermostat, and we will set the desired temperature with them.

Before turning on the heating element, you need to transfer the soldering iron from the traveling position to the combat position. Screw the stand to it and install the nozzles for soldering pipes in place. As a rule, there are two holes for nozzles on the sole of the soldering iron, if you work with different pipe diameters, you can install two nozzles at once. Place the nozzle for pipes of smaller diameter on the edge of the spout, as shown in the figure.

After that, you can turn on the soldering iron in the network. Turn on both heaters on the body of the soldering iron and set the temperature to 260⁰C. And be patient, the soldering iron should heat up for 10-30 minutes until the light on the body goes out. After that, we wait another 5 minutes before soldering, so that the soldering tips warm up well.

How to connect plastic pipes

Heat the pipe and fitting socket with a soldering iron at the same time. Below is a table that shows the heating time for different pipe diameters.

Heating time for brazing polypropylene pipes

Pipe outer diameter, mm
Distance to the mark, mm
Heating time, s
Technological pause no more than, s
Cooling time, min.

For branching or wiring various water communications (heating, sewerage and plumbing systems), it is necessary to use special technologies. Soldering plastic pipes can be done by professionals, but it is also easy to do it yourself.

Soldering tools

To interconnect the individual parts of the water supply, it is necessary to use temperature exposure technologies. Soldering or welding plastic pipes allows the diffusion of plastic molecules, resulting in a strong and tight connection.

Photo - apparatus for soldering plastic communications

These works are carried out with the help of special devices – welding inverter for plastic pipes or gun:

The welder is considered a more professional machine and is mainly used by experienced plumbers. Its price is an order of magnitude higher than a standard household pistol;
The gun is a kind of soldering iron, which can act pointwise on individual parts of plastic or metal-plastic communications.

Welding machines can be classified by power. Now the most popular are universal models for 1500-1600 watts. They are convenient for domestic use, in addition, the kit also comes with a set of nozzles for working with various types pipelines.

Photo - soldering iron design

It should be noted that in addition to special devices, additional tools will also be needed. In particular, these are scissors for cutting plumbing parts. As well as a roller pipe cutter, which allows you to provide the most even and smooth cut on the surface of communications.

Also, when working with metal-plastic or foil-reinforced pipes, you will need a stripping tool - a grinder. It will even out the cut edge, on which small irregularities often remain after cutting the desired area. If you ignore this process, then the connection may not be strong enough and tight, which will affect the operation of the entire sewer system.

If soldering of plastic pipes of large diameter is required - from 110 mm, then an electric coupling is used. It is placed on the joint and heats up the joint. In the process, the main role is played by the centering of individual sections of communications, since it is almost impossible to control the process during welding. To work with such a device, a special centering machine is used, which allows you to level the cut surface in order to obtain the most dense seam. The power of the couplings is somewhat different from the power of welding machines and soldering guns, in most cases slightly higher values are required - over 1500 watts.

Cold soldering is also often used at home. The technology involves the use of an aggressive adhesive that ensures the diffusion of plastic molecules without the use of heating elements. The main advantage of the method is simplicity. Such welding is easily done even without experience, in addition, the purchase of additional devices is not required. But at the same time, such a soldering is considered short-lived, that is, it is rather an urgent measure than an option for a permanent connection of pipes.

Photo - an example of cold soldering of plastic communications

You can buy a tool for soldering plastic pipes in almost any plumbing store, on average it costs from 800 rubles to several tens of thousands. For example, in Sevastopol, the cost of WESTER DWM 1000B varies from 1800 to 2000 rubles. The price depends on the declared power of the device, brand and its purpose.

Video: how to solder plastic pipes

Soldering instructions

Self-welding of plastic pipelines is carried out using the sewerage project and in accordance with GOSTs. For each material, soldering is carried out in accordance with certain temperature, the table below will help you choose the right values:

Diameter, mm	Heating, seconds	Welding, seconds	Cooling, seconds
16	6	4	3
20	6	4	4
25	7	4	4
32	9	4	4
40	12	5	4
50	17	5	5
63	23	5	5
75	30	7	7
90	38	7	8
110	48	9	10
160	80	14	14

Step-by-step instructions on how to solder plastic pipes of heating systems or connect water pipes:

Special nozzles must be installed on the welding device, for example, fittings for 25 mm pipes. Using the table, the time of their heating is determined, the temperature, according to the norms, is at around 260 degrees. This is the optimal parameter for soldering conventional plastic and reinforced pipes;
After preparing other plumbing tools. Be sure to check that the cutter is sharp before cutting. For small diameters, it is recommended that the cut be made not at a right angle, but at 45 degrees;

Photo - soldering kit
Now you need to measure the size of the fitting on the pipe and take into account the gap of 1 mm. It must be present when joining. Mark it on the communication. This is very important, because the fitting cannot be pushed all the way in; after heating, the plastic will expand slightly;
A fitting must be put on a preheated nozzle, after which a pipe must be inserted into another hole in the connecting part. Further, the gun heats up and the nozzle warms up again along the entire length;

Photo - heating elements
It remains to carefully remove the heated parts and connect them. The result will be a strong and tight mount with a fitting;
The next stage of soldering pipes includes reheating the soldering iron, but only now a piece with a fitting is put on the nozzle, and the free part of the communication is inserted into another hole;
After heating, the operation is repeated: the parts are removed from the nozzle and connected.

When the work is finished, you need to wait for the specified time to cool the connection, some craftsmen also use a hair dryer to speed up the process.

Photo - hair dryer for plastic

Sometimes a heating iron cannot be used and the use of electric couplings is required. Their principle of operation is very similar to that described above, the main difference is that for such pipe soldering, the entire apparatus is heated, and not its individual nozzles.

Before starting welding, it is imperative to degrease the segments, as well as clean them from dust and dirt. To do this, wipe the fitting and coupling with alcohol on the inside, and the pipe on the outside. Soldering is done in the same way as mentioned earlier.

Do not apply too much pressure when connecting the pipe to the fitting. After soldering, the plastic becomes more pliable, due to which, with excessive pressure, wrinkles may appear inside the pipe;
Do not allow the fitting to move freely along the pipe;
Keep a close eye on the heating time and temperature. If you exceed or, conversely, reduce these indicators, then the fastening will turn out to be fragile;
When working at home with water or sewer pipes, leave a gap of no more than 1 mm at the attachment point, otherwise there will be leaks in this area.

The ability to assemble pipelines on your own is a definite plus of polypropylene products. Using a convenient and lightweight material, you can build a sewer with your own hands, repair and modernize the water supply system.

The main thing is to understand the specifics of connecting prefabricated elements to each other. Agree, this is an important part of the work, responsible for the tightness of the line and its trouble-free operation.

We offer you detailed information on how polypropylene pipes are soldered, what equipment is used in the work, and we also list the most common mistakes novice welders make.

The information we offer will help to build trouble-free communications. For visual perception, the article is supplemented with graphic applications and a video guide.

The soldering process is carried out due to the pronounced thermoplastic properties of the material. Polypropylene softens when heated - it acquires a state similar to plasticine.

Image gallery

This is what a soldering iron ("iron") for polypropylene pipes looks like. A simple electrical device, semi-automatic, thanks to which plastic is soldered

For butt welding, the designs of soldering irons differ increased complexity. Usually, such equipment includes not only a heating element, but also a system for centering the parts to be welded.

As a rule, direct welding equipment, like the technology itself, is rarely used in the domestic sector. The priority of use is industry.

A more complex device, which is used to accurately center the parts to be welded with a further heating and soldering process. Used with direct welding technology

In addition to soldering irons, the master will also need:

scissors - ;
roulette construction;
locksmith's square;
shaver for pipes with reinforcement;
marker or pencil;
surface degreaser.

Since the work is carried out on high-temperature equipment, be sure to wear thick work gloves.

Polypropylene Welding Procedure

Important warning! Welding work polymer materials should be carried out in a well ventilated area. During heating and melting of polymers, toxic substances are released, which in a certain concentration have a serious impact on human health.

The procedure for welding polypropylene is simple, but requires accuracy and accuracy in work. Common mistakes should also be avoided, such as insufficient or excessive heating.

First of all, you need to prepare for work:

Install blanks of the required diameter on the heater plateau.
Set the regulator to 260ºС.
Prepare mating parts - mark, chamfer, degrease.
Turn on the soldering station.
Wait for a set operating temperature– turning on the green indicator.

The mating parts (pipe - coupling) should be simultaneously placed on the blanks of the soldering station. In this case, the polypropylene pipe is mounted in the inner region of one blank, and the coupling (or socket of the fitting) on the outer surface of the other blank.

Usually, the ends of the pipe are inserted along the border of the previously marked line, and the coupling is pushed all the way. When keeping polypropylene parts on heated blanks, you should remember about important nuance technology - exposure time.

Image gallery

Conclusions and useful video on the topic

Professionals always have something to learn. How to work with polypropylene can be seen in the following video:

Mounting pipelines made of polymers by soldering them “hot” is a convenient and popular technique. It is successfully used in the conditions of installation of communications, including at the household level.

People without experience can use this welding method. The main thing is to correctly understand the technology and ensure its exact execution. A technological equipment can be bought or rented.

Do you have experience in soldering polypropylene pipes? Please share information with our readers. You can leave comments and ask questions on the topic in the form below.