How to solder plastic pipes with your own hands - detailed instructions. How to solder plastic pipes How to solder pvc pipes with a soldering iron

For those who know how to solder plastic pipes, arrangement heating system, hot or cold water supply and other domestic piping will not be too complicated. The assembly of such systems requires, first of all, a reliable pipe connection, which determines the quality of all the work done.

Photo 1. Design of a soldering iron for plastic pipes.

Weld them out various kinds plastic is not as difficult as it may seem. Polypropylene, polyethylene and others polymer materials they are quite malleable in work, do not require too complicated equipment, their melting point is much lower than that of iron, their weight is relatively small, as is their rigidity. But knowledge about the specifics of each material, about what to do and in what sequence, is necessary.

Necessary tools and materials

Do-it-yourself welding of polypropylene pipes requires a certain set of tools and materials. It makes sense to briefly list them at the beginning and figure out what and what is intended. So, in order to weld pipes with high quality, you need:

• a special soldering iron or attachments for a household soldering iron;
• a set of nozzles for such a soldering iron;
• secateurs (scissors) designed for even cutting of pipes;
• plastic pipes;
• couplings (fittings) of various types;
• adapters for threaded connections;
• shaver;
• trimmer;
• degreaser for plastic pipes.

How to solder polypropylene pipes? This question is asked by beginners. Photo 1 shows that the design of the soldering iron is rather unusual. It is designed to heat plastic, more precisely, pipes of a certain diameter. After all, the installation of plastic pipelines is mainly the welding of components. Such a soldering iron is an analogue of a welding machine used to join steel products.

Soldering iron tips are designed to be able to work with pipes and fittings of small or large diameter. They are usually sold as a set.

Instead of scissors for cutting plastic pipes, it is quite possible to use an ordinary hacksaw for metal. But then it will be quite difficult to get an even cut at a right angle, and the cutting process itself will take too much time. With a secateurs, even a person without special skills will cut the tube evenly.

Plastic pipes are all welded using almost the same technology, but there are some differences. PVC, polypropylene, polyethylene, for example, have different melting points. There are also reinforced pipes, which must be cleaned of reinforcing material before welding.

Couplings, or fittings, connecting elements for various purposes. For example, fittings for connecting threaded connections, called Americans, tees, angles with different bending angles, ordinary couplings, etc. As you might guess, the inner diameter of the connecting elements is approximately equal to the outer diameter of plastic pipes.

A shaver is a tool designed to strip the reinforcing layer that is on top. If this reinforcing layer is internal, a trimmer is already needed to clean it.

In order to make the connection more durable, the soldering point must first be degreased. For this, fat-dissolving compounds are used, ethanol or others.

In addition to the tools described, you may need a building level, special markers, etc., but they will be needed when the actual assembly is carried out, for example, heating systems.

Step-by-step description of welding polypropylene elements

As an example, it is worth describing the process of connecting polypropylene pipes. They are the most common, used in reinforced and unreinforced form for the arrangement of almost any domestic piping system.

The technology for welding polypropylene pipes, as noted above, is based on a relatively low melting temperature of the source material. Actually, this is the basic property of polypropylene or other plastic, which determines the relatively low cost of installing pipelines.

When soldering pipes, the starting material for the manufacture of which is polypropylene, the following steps must be taken:

1. Cut the pipes to the required length using special scissors. The quality of the cut and its angle with respect to the center line of the pipe must be carefully checked.
2. Choose fittings, taking into account their purpose and diameter.
3. Degrease those sections of the pipe and fitting that will be welded. The pipe must be degreased from above, the fitting - inside.
4. Turn on the soldering iron, equip it with nozzles of such a diameter that are needed for soldering pipes. It should be borne in mind that the soldering iron heats up for a long time, so you can turn it on in advance. Its operating temperature is in a certain range; for adjustment, there is a regulator that must be set to the position required for a particular type of pipe.
5. If reinforced pipes are being welded, it is necessary to first clean the junction from the reinforcing layer. For this, a trimmer or shaver is used, which must be prepared in advance.
6. Insert the pipe into the nozzle prepared for it on the soldering iron. Put the fitting on the nozzle, as its inner side will be heated. The heating time depends on the parameters of pipes and fittings, which will be discussed below.
7. After the heating is completed, insert the pipe into the fitting, pressing it to the stop. It is necessary to carefully control the insertion angle so that the connection does not turn out uneven. Each pipe and each fitting has a special strip in the form of a convex profile that indicates the direction of welding. If such strips are placed one opposite the other during soldering, even a fairly complex system of pipes will be in the same plane.
8. The welding time of polypropylene pipes is several minutes, so they must be postponed until they are completely hardened, after which it is already possible to start mounting on the wall.

As you can see, it is not so difficult to carry out the welding process on your own. But in fact, it is necessary to practice a little before the actual application of the knowledge acquired from the material presented. The training won't cost too much as unreinforced pipes and fittings are quite cheap. A mistake in real work will lead to the need to start all over again, wasting time and materials.

It is already clear how to solder polypropylene pipes, the time has come to deal with some process parameters.

Parameters to consider when welding pipes

Types of plastic pipes: 1 - polyethylene, 2 - polypropylene, 3 - metal-plastic.

Each plastic melts at a certain temperature, and this must be taken into account when welding. In addition, there are also concepts such as recommended operating temperature and softening temperature.

For example, polypropylene melts when heated to 175°C. But if the temperature is 30 °C lower, the material begins to soften, which leads to irreversible deformation. With these parameters, manufacturers of polypropylene pipes recommend an operating temperature not exceeding 95 °. For pipelines through which, for example, boiling water moves, these pipes will not work. But if they are reinforced with aluminum or other metal, they can also be used for hot environments.

Welding, in which polypropylene pipes are guaranteed to be securely connected, can only be carried out under certain parameters environment. At least the room where it is held should be warm. No manufacturer recommends carrying out this kind of work at sub-zero temperatures. And the accuracy of a person’s work in the cold is a rather relative concept.

Conclusion on the topic

An important point is the heating time of pipes and fittings with a soldering iron.

For example, if thermometers fix 20 ° C at the workplace, then for a pipe with a diameter of 20 mm with a welded belt width of up to 16 mm, 6 seconds must be spent on heating, 4 seconds on the connection and 2 minutes in order for this connection to completely harden.

The table of ratios of diameters, the length of the welding site and the time spent on basic operations should be a guide to action for those who are going to weld plastic pipes for various types of pipelines.

Repair is a rather expensive pleasure, so many people prefer to do it themselves to save money. But if wallpapering and laying linoleum are considered simple types of repairs, then laying or replacing communications requires certain skills and special equipment.

For example, many are afraid of the need to connect plastic pipes when repairing a water pipe. In fact, there is nothing complicated in this, it is enough to get a welding device for plastic pipes and study some of the features of the process.

To carry out welding work with plastic pipes, you will need the following tools:

• construction tape measure and a pencil (marker) for taking measurements,
• pipe cutter or construction knife for cutting pipes,
• shaver (if welding of pipes reinforced with aluminum foil is carried out),
• a file and fine-grained sandpaper for grouting burrs on cut pipes,
• pipe welding machine.

You will also need alcohol to degrease structural elements in the places of welding and rags.

What is a plastic pipe welding machine

The action of the welding machine for plastic pipes is to heat the ends of the pipe and fitting, which will be connected to each other, to a temperature close to melting. Due to the softening of the material after cooling, they form a single monolithic structure.

The device itself consists of a support platform and a body equipped with:

• temperature controller,
• light indicators of the operating status of the device,
• heating element (mirrors, soles),
• knobs for adjusting the position of the mirror.

There are two holes in the sole of the device, on which nozzles are attached, corresponding to the diameters of plastic pipes. The most common nozzles allow you to weld pipes from 16 to 32 mm, the maximum possible diameter is 63 mm.

Healthy! During operation, the sole and the nozzles attached to it are heated to the same temperature, which allows you to securely connect the pipeline elements without worrying that one of them has not warmed up enough.

There are 2 types of welding machines for plastic: xiphoid and cylindrical. The xiphoid apparatus is sufficient for use in living conditions, but this tool has one drawback - rather poor stability.

If you decide to make plumbing for your home on your own, then know that best material for this there will be plastic pipes. In order to single system, you need to understand how plastic is welded. However, do not let this scare you, since the process of soldering plastic pipes is not particularly difficult and does not require a large number special tools.

For the production of welding work you will need:

• roulette;
• marker;
• building level;
• scissors for cutting plastic pipes;
• welding device for plastic pipes.

All tools, except for the last one, are available to almost any artisan. You may need the latter only once in your life, so it is much more expedient not to buy it, but to borrow or rent it.

Briefly about the welding machine

Before you start soldering, you should briefly get acquainted with the device that you are going to use.

An important element is the sole, equipped with heating elements. The convenience of work is ensured by the fact that there are holes on the sole that allow you to fix special nozzles for soldering. Temperature control is carried out using a thermostat located on the body.

Pipe soldering process

When starting soldering, the device must be installed in the desired position and the nozzles must be fixed on it. right size. Using the thermostat, set the desired temperature:

• 260°C for polypropylene pipes;
• 220°C for polyethylene pipes.

Allow the device to warm up for 10-20 minutes until the indicator goes out.

When soldering, it is necessary to proceed from the following data:

External pipe size, mm
Interval to the mark, mm
Heating time, sec
Maximum duration of technological pause, sec
Cooling time, min

The soldering process is reduced to the following operations:

• Using special scissors, cut the pipe to the required length, using alcohol solution clean the joints from dirt and grease;
• Install the pipe and the reciprocal socket into the nozzle and warm up for the time indicated in the table;
• Connect the heated elements to each other by inserting the pipe into the socket. This operation must be performed within the time period indicated in the table as a technological pause;
• After completing the operation, check the quality of the resulting welded joint, which will be noticeable in the form of plastic rings.

We have just outlined the essence of the soldering process. However, to ensure the reliability of the operation of the pipeline, attention should be paid to the following details:

• The first welding operation should be carried out five minutes after the soldering iron has warmed up.
• If it is necessary to weld reinforced pipes, a special tool called a shaver should be used to remove aluminum and polypropylene from the pipe, which form the two upper layers. After that, the joining of the pipes is carried out according to the method already described.
• Welding work should be carried out only when the ambient temperature is above zero.
• After welding, allow the connected pipes to cool, preventing them from twisting or moving relative to each other. In the event that the connecting seam turned out to be of poor quality, the assembly must be cut and the welding process must be performed again.

When working with, certain precautions must be observed, the non-observance of which may affect the quality of the welded joints. In particular, it must be remembered that the nozzles have a Teflon coating that prevents the formation of carbon deposits. At the end of each operation, melted residues must be removed from them with a wooden spatula. It is strictly forbidden to remove residual material after the tips have cooled down, as this may damage the coating and cause a malfunction of the entire device.

Any modern housing, be it a private mansion or city ​​apartment, must be equipped with a variety of engineering communications. And if so, then either during the construction process, or during repairs or reconstruction, sooner or later the owners will have to face the problem of installing or replacing pipes - and heating systems. Few people are now attracted by the laborious and rather complicated installation of VGP steel pipes. They are expensive in themselves, require considerable additional costs for transportation, and their processing and connection are associated with specific operations that not everyone can do - cutting, bending, electric or gas welding, threading, etc. Plus, to the "packaging" of each threaded connection a special approach is required to ensure that the connecting node is of high quality, without leaks.

How good that modern technologies allow you to do without all this trouble by using polypropylene pipes. At right choice material and high-quality installation, plumbing and heating circuits practically do not recede in anything to steel ones, in many respects they are far superior to them. In addition, the soldering of polypropylene pipes itself is not so complicated, the instructions for which will be discussed in this publication.

Not all polypropylene pipes are the same

Before starting to consider the installation instructions for polypropylene pipes, it makes sense to give at least general concept about this material, in particular - about its varieties and areas of application. The choice of pipes according to the principles “which is cheaper” or “what were” is completely unacceptable. The consequences for an indiscriminate home master can be very sad - from the deformation of the laid pipeline to its rupture or the appearance of leaks in the connecting nodes.

The difference in diameter does not need to be explained - in different systems and in their various sections their sizes are used, which are predetermined by hydraulic calculations. The range of diameters, from 16 to 110 mm, allows almost complete provision of all possible options. Moreover, practice shows that for a house or apartment, an assortment of up to 40 mm is usually enough, much less often - up to 50 ÷ 63 mm. Pipes larger diameter- it is rather the main ones, and they have specific features Mounting but facing it home master- is unlikely to be necessary.

The difference in color between some types of pipes may immediately catch your eye. This is the least you can pay attention to - white, green, grayish and other walls - do not say anything. Apparently, this is just a decision of manufacturers to somehow distinguish their products from the general background. By the way, for heating circuits White color it will definitely be preferable, since the pipeline will unobtrusively fit into any interior, without creating a disharmonious color “spot”.

But the colored bars, if they exist, already carry an informative load, intuitively understandable to everyone. The blue stripe - the pipe is designed exclusively for cold water supply, the red one - is able to withstand elevated temperatures. However, such a color marking (which, by the way, very often does not exist at all) is only very approximate, not fully revealing the operational capabilities of a particular pipe. It helps not to make a mistake during the installation of the system. By the way, the longitudinal line is also good because it becomes a good guide when joining mating parts during soldering.

Much more information is given by alphanumeric marking, which is usually applied on the outer wall. This is where you should be more careful.

The international abbreviation for polypropylene is PPR. There are several varieties of material, and you can find the designations PPRC, PP-N, PP-B, PP-3 and others. But in order not to completely confuse the consumer, there is a clearer gradation of pipes - by type, depending on the allowable pressure of the pumped liquid and its temperature. There are four such types in total: PN-10, PN-16, PN-20, PN-25. In order not to talk for a long time about each of them, you can give a plate that characterizes the operational capabilities and scope of pipes.

polypropylene pipes

Type of polypropylene pipes	Working pressure (nominal)		Pipe Applications
	MPa	technical atmospheres, bar
PN-10	1.0	10.2	Cold water supply. As an exception - supply lines to the contours of the water "warm floor", with a maximum operating temperature of the coolant up to 45 ° C. The material is the most affordable in terms of cost - due to not particularly outstanding physical, technical and operational parameters.
PN-16	1.6	16.3	The most popular option for autonomous systems of cold and hot water supply, with an operating temperature of not more than 60 ° C, a pressure of not more than 1.6 MPa.
PN-20	2.0	20.4	Cold and hot autonomous or central water supply. It can be used in autonomous heating systems, where there are guaranteed to be no water hammers. The coolant temperature must not exceed 80 ˚С.
PN-25	2.5	25.5	Hot centralized water supply, heating systems with coolant temperature up to 90÷95˚С, including central ones. The most durable, and also the most expensive type of pipe.

Of course, in order for the pipe to withstand elevated pressures and temperatures, it must have thicker walls. The value of the wall thickness and, accordingly, the nominal diameter of polypropylene pipes various types– in the table below:

Pipe outer diameter, mm	Type of polypropylene pipes
	PN-10		PN-16		PN-20		PN-25
	Passage diameter, mm	Wall thickness, mm	Passage diameter, mm	Wall thickness, mm	Passage diameter, mm	Wall thickness, mm	Passage diameter, mm	Wall thickness, mm
16	-	-	11.6	2.2	10.6	2.7	-	-
20	16.2	1.9	14.4	2.8	13.2	3.4	13.2	3.4
25	20.5	2.3	18	3.5	16.6	4.2	16.6	4.2
32	26	3	23	4.4	21.2	5.4	21.2	3
40	32.6	3.7	28.8	5.5	26.6	6.7	26.6	3.7
50	40.8	4.6	36.2	6.9	33.2	8.4	33.2	4.6
63	51.4	5.8	45.6	8.4	42	10.5	42	5.8
75	61.2	6.9	54.2	10.3	50	12.5	50	6.9
90	73.6	8.2	65	12.3	60	15	-	-
110	90	10	79.6	15.1	73.2	18.4	-	-

With all the advantages of polypropylene, it also has a rather significant drawback - a very significant linear expansion when heated. If for cold pipelines located inside the building, this is not so significant, then for hot water pipes or for heating circuits, this feature can lead to deflection, sagging of long sections, deformation of complex interchanges, and the appearance of internal stresses in the pipe body, reducing its service life.

To minimize the effect of thermal expansion, pipe reinforcement is used. It can be aluminum or fiberglass.

The fiberglass reinforcing belt is always located approximately in the center of the pipe wall thickness, and does not affect the soldering technology in any way.

But with aluminum - a little more complicated. There are two types of such reinforcement. In one case, the foil layer is located in close proximity to the outer wall of the pipe (bottom left in the illustration). Another option - the reinforcing belt runs approximately in the center of the wall. For each type of such reinforcement, there are special technological nuances of installation, which will be discussed below.

Both fiberglass and aluminum reinforcement significantly reduces the thermal linear expansion of polypropylene pipes. In addition, the aluminum layer also performs another function: it becomes a barrier against oxygen diffusion - the penetration of oxygen molecules from the air through the pipe walls into the coolant.

The penetration of oxygen into the liquid medium of the coolant can cause a series negative consequences, among which the main ones are increased gas formation and activation of corrosion processes, which is especially dangerous for metal parts boiler equipment. The reinforcing layer is able to repeatedly reduce this effect, so such pipes are most often used specifically for heating circuits. In plumbing systems, it is quite possible to get by with fiberglass reinforcement, which does not have a significant effect on diffusion.

Types of polypropylene pipes	Designation	Thermal expansion coefficient, m×10 ⁻⁴ /˚С	Oxygen diffusion indicators, mg/m²× 24 hours
Single layer pipes:
	PPR	1.8	900
Multilayer pipes:
Polypropylene reinforced with fiberglass.	PPR-GF-PPR	0.35	900
Polypropylene reinforced with aluminium.	PPR-AL-PPR	0.26	0

The illustration below shows an example of marking a polypropylene pipe:

1 - in the first place is usually the name of the manufacturer, the name of the pipe model or its article.

2 - material of manufacture and structure of the pipe. In this case, it is a single-layer polypropylene. Pipes with fiberglass reinforcement are usually marked PPR-FG-PPR, with aluminum - PPR-AL-PPR.

There may be reinforced pipes with an outer polypropylene layer and an inner wall made of cross-linked polyethylene. They will have a designation such as PPR-AL-PEX or PPR-AL-PERT. This does not affect the soldering technology, since the inner layer does not participate in it.

3 is the standard pipe dimension coefficient, equal to the ratio of the outer diameter to the wall thickness.

4 - nominal values ​​of the outer diameter and wall thickness.

5 - the type of pipe mentioned above according to the nominal working pressure.

6 - a list of international standards to which the product complies.

Pipes are usually sold in standard lengths of 4 or 2 meters. Most retail outlets practice selling with a cut that is a multiple of 1 meter.

Numerous accessories are on sale for all pipes - threaded fittings, for switching to another type of pipes, with external or internal thread or with an American union nut, couplings, tees, transitions in diameters, bends at an angle of 90 and 45 degrees, plugs, bypass loops, compensators and others necessary details. In addition, it is possible to purchase taps, valves, manifolds, "oblique" coarse water filters designed for direct soldering into polypropylene piping.

In a word, such a variety allows you to choose the most convenient scheme for assembling a system of almost any degree of complexity. The cost of most of these parts is very low, which allows you to purchase them with a certain margin, at least in order to conduct a small training session before starting practical installation - so to speak, “get your hand on”.

Methods for connecting polypropylene pipes

Polypropylene is a thermoplastic polymer - when heated, its structure begins to soften, and when two fragments evenly heated to a certain temperature are joined, mutual diffusion occurs, or rather, even polyfusion, that is, interpenetration of the material. When cooling, the properties of polypropylene do not change, and with a quality connection - ensuring optimal heating and the required degree of compression, after the reverse polymerization of the boundary as such, there should not be a completely monolithic assembly.

It is on this property that the main technological methods for connecting polypropylene pipes are based - this method is often called polyfusion welding.

Such welding (soldering) can be carried out by coupling or butt welding.

• Sleeve welding is just the technology that is most often used when installing plumbing or heating circuits in a house or apartment. It is designed for pipes of small and medium diameter, up to 63 mm.

Its meaning is that any connecting unit involves the use of two parts - this is the pipe itself and the coupling, the inner diameter of which is somewhat smaller than outside diameter pipes. That is, in a normal, “cold” form, the parts cannot be paired. The coupling can act not only, sorry for the tautology, the coupling itself, but also the mounting section of the tee, branch, tap, threaded fitting and other components.

The principle of such welding is shown in the diagrams below.

The pipe (pos. 1) and the coupling or any other connecting element (pos. 2) are simultaneously mounted on the heating elements of the welding machine.

Steam is pre-installed coaxially on the working heater itself desired diameter, consisting of a metal sleeve (pos. 4), into which the pipe will be inserted, and a mandrel (pos. 5), on which the necessary connecting element is put on.

During the heating period, a belt of molten polypropylene is formed along the outer surface of the pipe and the inner surface of the coupling, approximately the same width and depth (pos. 6). It is important to choose the right warm-up time so that the melt process does not capture the entire wall of the pipe through and through.

Both parts are simultaneously removed from the heater, and coaxially, with force, are connected to each other. The molten plastic outer layer of polypropylene will allow the pipe to fit tightly into the sleeve until it stops, for the length of the heated section.

At this stage, the process of polyfusion, cooling and polymerization takes place. As a result, a reliable connection is obtained, which, although shown in the diagram by a shaded area (pos. 7), but in reality, if you look at the section, you can’t see it at all - it’s almost a monolithic wall.

• Butt welding is done a little differently.

One of the main differences is that the parts that are joined must be the same in inner and outer diameter.

The first step is to fine-tune the ends so that they fit perfectly together.

Pipes are pressed from both sides with a facer - a rotating disk (pos. 2) with precisely set knives (pos. 3)

The pipes are again pressed to the center, and at the ends, for the entire thickness of the wall, polypropylene melting areas are formed (pos. 5).

And, by analogy with the previous case, as the weld cools, it polymerizes, creating a reliable connection between the two pipes.

The principle seems simple, but it is only at first glance. With this welding technology, the most accurate alignment of the mating parts is of decisive importance. In addition, in sleeve welding, the required degree of compression of the mating melted areas is provided to a greater extent by the difference in the diameters of the parts. In this case, the application of a significant external force is required, directed strictly along the axis of the connected pipes. All these conditions can be met only when using a special, rather complex machine-type apparatus.

There are many devices for butt welding, but almost all of them have a powerful frame with guides and clamps for clamping pipes of various diameters - to ensure the alignment of the connection, removable or reclining trimmer and heater, a mechanism for creating the required compression - manual, hydraulic, electric, etc. .P.

This technology is used, as a rule, only by professionals when laying main pipes, and the probability of encountering it at the household level is practically zero.

There is also a "cold" method of welding - using glue based on a potent organic solvent. The point is that when treated with such a composition, the surface layers of the polymer soften. Parts can be connected at this time in the desired position, and since solvents are usually highly volatile, they evaporate quickly. then the process of reverse polymerization begins quite quickly.

This technology is more suitable for polyvinyl chloride (PVC) pipes that do not have the proper thermoplasticity. In addition, a similar connection method has, perhaps, more disadvantages and limitations in use than advantages, therefore it is not in particular demand, especially since there is a simple and accessible technology for socket polyfusion welding.

What is required for installation work

So, in the future we will consider exclusively sleeve polyfusion welding (soldering). To cope with this task yourself, you need to prepare a number of tools and accessories.

• First of all, it is, of course, a machine for welding polypropylene pipes. There is such a tool - not so expensive, and many zealous owners already have it in their home "arsenal".

Coupling-mandrel kits of the required diameters must be attached to the welding machine. Most devices allow you to simultaneously place two, and sometimes three pairs of working nozzles on their heating element, which allows you to install a system that uses pipes of various diameters without interruptions for replacement.

If you don’t have your own device, and circumstances at the moment do not allow you to purchase it, then many salon shops practice short-term rental with a daily fee - you can take advantage of this opportunity.

If you decide to buy a machine for welding polypropylene pipes ...

All welders They are arranged in approximately the same way and work on a similar principle, but they also have certain differences in layout and functionality. Useful information for those who decide to make such a purchase, it is placed in an article on our portal, specially dedicated to.

In the text, there may be a definition of an apparatus for soldering pipes - but this is just a "play on words." There is no difference between these concepts in this case.

• Pipe cutting requires special scissors. Moreover, they must be sharply honed, with a serviceable ratchet mechanism that provides a smooth cut. The blade must be free of nicks or warps.

Of course, you can cut the pipe with a hacksaw, just with a metal blade or even a “grinder”, but this is absolutely not a professional approach, since such tools cannot achieve the required accuracy and evenness of the cut.

machine for welding polypropylene pipes

• It is necessary to prepare a marking tool - a tape measure, a ruler, a building square, a marker or a pencil. To properly place the pipes, you have to resort to the help of a level.
• If you plan to solder polypropylene pipes with aluminum reinforcement, then additional tools are needed.

- if the pipe has external reinforcement, then a shaver will be required, which will clean the aluminum layer at the point of penetration.

- if the aluminum reinforced layer is located deep in the wall thickness, then the pipe still requires preliminary preparation, but in this case a trimmer is already used.

The trimmer outwardly often looks like a shaver, but there is a difference between them - it lies in the location of the knives. For a shaver, the cut is tangentially parallel to the axis of the pipe, and for a trimmer, as even their names are clear, the knife processes the butt and removes a small chamfer.

Read a useful article, and also check out the varieties and selection criteria on our portal.

We will dwell on this point in more detail when considering the technology of soldering pipes.

• Many people overlook this, but the welded sections of pipes and couplings must be cleaned of dirt, dust, moisture, and then degreased. This means that it is necessary to prepare a clean rag and an alcohol-containing solvent (for example, ordinary ethyl or isopropyl alcohol).

But solvents based on acetone, esters, hydrocarbons should not be used, since polypropylene is not resistant to them, and the walls can float

• Care must also be taken to protect the hands. They will have to work in close proximity to the heating element of the apparatus, and getting a serious burn is as easy as shelling pears.

Suede work gloves are best for this business - they practically do not restrict movements, they will not start to smolder from contact with a hot heater, and they will reliably protect hands.

And one more important warning. Majority installation work very often it can be carried out out of place, but, for example, on a workbench in the workshop - some devices even have special brackets with clips for secure fixation on the table. This is convenient in the sense that the assembled unit is then quickly installed, for example, in cramped and uncomfortable conditions in a bath or bathroom.

In any case, wherever soldering is carried out, high-performance ventilation must be ensured. When polypropylene is heated, a gas with a pungent odor is released. The smell is not the worst thing - with prolonged inhalation, serious intoxication can occur. Believe me, I've tested it on my own skin. The author of these lines lay around for a day with a temperature of 39 ° after seven hours of work in a fairly spacious combined bathroom, with a seemingly well-functioning ventilation outlet. Do not repeat mistakes!

How to solder polypropylene pipes

General technological methods for welding polypropylene pipes

• First of all, the novice master must clearly understand what he is going to mount. Must be prepared detailed diagram-drawing, with dimensions and specific details - the same "document" will become the basis for the purchase required amount pipes and accessories.
• If conditions permit, for example, in the room where the installation will be carried out, there is still no finishing, then it is best to transfer the scheme directly to the walls - this will be more clear, and you can measure the required pipe lengths literally in place.

The key to success is to try to complete the maximum possible number of nodes in a comfortable working position, on a workbench. Working with a soldering iron directly on site, and even alone, without an assistant, is an extremely difficult task, and it is very easy to make an error in this case. It is clear that such operations cannot be completely avoided, but their number should be reduced to a possible minimum.

• The soldering iron is getting ready for work. On its heater, working pairs are put on and tightened with a screw - couplings and mandrels of the diameters necessary for operation. If it is supposed to work with one type of pipe, then there is nothing to be wiser - one pair is put on, as close as possible to the end of the heater.

There are welding machines with cylindrical heating elements - it has a slightly different fastening of working elements, like a clamp. But understanding this is easy.

• It will be much more convenient to work if the device is rigidly fixed to the working surface of the workbench. It's great if the design provides for a clamp-type screw for mounting on the edge of the tabletop. But even with a conventional apparatus, you can try to come up with some kind of fixation. For example, if the surface allows, the legs of the stand are screwed to the workbench with screws.

Even with a fixed stand, the device can "wobble" in it - there will definitely be a backlash. Here, too, you can provide for your own fastening - drill a hole and screw in a self-tapping screw. When a soldering iron is needed for remote work, removing this mount is a matter of a few seconds.

• The soldering iron is connected to the network. If it has a temperature control, then approximately 260 ° C is set - this is the optimal temperature for working with polypropylene. You should not listen to anyone that for the 20th pipe you need 260 degrees, for 25 - already 270, and so on - on the rise. The temperature is the same, the heating time of the mating parts just changes. In any case, those tables that the manufacturer attaches in the product passport, and which will be placed below in this article, are designed specifically for this level of heating.
• Usually there is a light indication on the soldering iron. A burning red light indicates that the heating element is working. Green - the device has reached the operating mode.

However, many models have their own display features. Some devices even have a digital display with temperature indication. In any case, the device will “let you know” that it has warmed up to the required level.

• The mating parts are being prepared for work - the necessary piece of pipe is cut off, the connecting element is selected, according to the installation scheme.

• Not many people do this, but meanwhile the technology requires - obligatory cleaning of the connection area from possible dirt and dust, and degreasing. In addition, even the slightest droplets of water or a wet surface are completely unacceptable - water vapor can enter the melt layer, create a porous structure there, and this connecting unit runs the risk of leaking sooner or later.
• The next step is to mark up the connection. On the pipe, it is necessary to measure from the end and mark the length of the penetration zone with a pencil (marker). It is up to this mark that the pipe will be inserted into the heating sleeve, then into the connecting piece. Each diameter has its own value - it will be indicated in the table below.

The second mark is applied if the relative position of the mating parts matters. For example, a 90° bend is already welded on one of the sides of a pipe segment, and on the other, let’s say, a tee is to be mounted, but so that its central channel is located at an angle to the bend relative to the axis. To do this, first accurately determine the position of the parts, and then put a risk across the border, on both.

There will no longer be a lot of time to choose the correct position during soldering, and such a “trick” will help to accurately position the mating parts.

• The next step is directly soldering the connection. It, in turn, also includes several phases:

- From both sides, the pipe is simultaneously inserted into the soldering iron coupling, and the connecting element is put on the mandrel. The pipe should go to the mark made, the connecting element - to the stop.

— Once the pipe and connector are fully inserted, the warm-up time begins. Each diameter has its own optimal time which should be followed.

- As soon as the time is up, both parts are removed from heating elements. The master has literally a few seconds to give the parts the correct position and, of course, alignment, insert one into the other with effort and bring it to the same mark. Light adjustment, without turning around the axis, is only allowed for one to two seconds.

- In this position, the parts must be held, without the slightest displacement, for the specified fixation period.

- After that, the assembled unit should not experience any load during the set period of cooling and polymerization of polypropylene. And only then can it be considered ready

Now - about the main parameters that must be followed during installation. For ease of understanding, they are summarized in the table:

The name of indicators	Pipe diameter, mm
	16	20	25	32	40	50	63
The length of the welded section of the pipe, mm	13	14	16	18	20	23	26
Heating time, seconds	5	5	7	8	12	12	24
Time for permutation and connection, seconds	4	4	4	6	6	6	8
Time to fix the connection, seconds	6	6	10	10	20	20	30
Time for cooling and polymerization of the node, minutes	2	2	2	4	4	4	6
Notes: - If welded thin-walled pipes type PN10, then the heating period of the pipe itself is halved, but the heating time of the connecting part remains the same as indicated in the table. - If the work is carried out on the street or in a cold room at a temperature below + 5 ° C, then the warm-up period is increased by 50%.

As for reducing the set warm-up time (with the exception of the case mentioned in the note to the table), there can be no question - a high-quality connection will not work, and the node will surely leak over time. But about some slight increase - the masters have no unity of views. The motivation here is that pipes from different manufacturers may differ slightly in material, that is, there are more rigid or, conversely, softer polypropylene. But the masters have accumulated experience, accurate knowledge of the material used, and for a beginner, the recommended indicators should still be taken as a basis.

Good advice - when buying pipes and accessories - take a small supply of the cheapest connecting elements, and conduct an experiment - training. You can prepare several pieces of pipe and perform trial soldering.

With high-quality soldering, a neat bead about 1 mm high is created around the circumference of the connecting node, which will not interfere with the free passage of water. Outside, a neat collar will also be formed that does not spoil appearance connections.

pipe cutter

But overheating is already fraught with getting a defective connection. Molten polypropylene begins to squeeze inward when the parts are combined, where a “skirt” is formed and solidifies, which largely closes the passage. The pressure of water in such a water supply can be reduced, and in addition, such a defect often becomes a place of blockage over time.

Conducting such a practical lesson will help you accurately determine all the soldering parameters and avoid mistakes.

Features of working with pipes with aluminum reinforcement

As mentioned above, two options are possible here - the reinforcement layer is located near the pipe surface, or in the depth of the wall. Accordingly, the methods of preparing the pipe for welding also differ.

• It is clear that the aluminum layer located near the surface simply will not allow for a full heating and connection of the assembly. In addition, such pipes always have a slightly higher diameter, and simply will not enter either the heating sleeve or the connecting element. This means that it is necessary to clean off this layer to “clean” polypropylene.

For this, a special tool is used - a shaver. A piece of pipe is inserted into it and they begin to turn - the installed knives carefully cut off the upper polymer coating and aluminum underneath.

Processing is carried out until the pipe stops at the bottom of the tool - the dimensions of the shaver are such that it cuts the foil exactly in the strip that is required for the welded joint at a given diameter, that is, you can even not carry out the appropriate marking.

When soldering, the entire cleaned area must be heated, and then completely inserted into the connecting part. Leaving even a thin strip of a protected pipe outside is prohibited.

• If the aluminum foil is hidden in the skin of the material, then it would seem that it does not fit in any way with high-quality soldering. But there is already another nuance here.

If the pipe is not protected from the end, then the water passing under pressure will try to delaminate it, find a way out between the aluminum layer and the outer polypropylene sheath. Aluminum, in addition, may begin to corrode, lose its strength. The result of such stratification first becomes "blisters" on the body of the pipe, which then necessarily end in a major accident.

The way out is to create such conditions that during welding the end of the pipe and the aluminum layer would be completely covered with molten polypropylene. And this can be achieved by processing with a special tool, which was mentioned above - with a trimmer.

Outwardly, it may be similar to a shaver, but its knives are located differently - they will precisely align the butt, cut off the chamfer and remove a thin, about 1.5 - 2 mm from the cut, strip of aluminum foil around the circumference. During heating and during the mating of parts, the created bead of molten polypropylene will completely cover the end of the pipe, and the assembly will receive the necessary reliability.

Pipes with fiberglass reinforcement do not have any installation features.

• The soldering process, as mentioned, is best done on a comfortable, spacious work site, assembling ready-made water supply units (heating circuits) to the maximum, and only then installing and connecting them in place.

Work “near the wall” is always more complicated, time-consuming and nervous, since one has to hold a fairly heavy apparatus with one hand, while simultaneously providing heating for both mating parts. Often, without an assistant, such a welded joint is almost impossible to perform. Therefore, it is worth minimizing the number of such operations.

But at the same time it is important not to make an oversight. To connect the assembly, it is necessary to provide a certain degree of freedom to the mating parts - they need to be moved apart to install a welding machine between them (plus, the heating pair also has a certain width), then carefully, without skew, insert into the mandrel and coupling, after warming up, ensure translational removal and then connection. It is necessary to foresee this moment in advance - will the existing backlash be enough to perform all these manipulations.

• It happens that inexperienced craftsmen, without foreseeing this nuance, are faced with the fact that the last weld is left, and there is no way to complete it. What to do?

The way out can be welding into a cut pipe a collapsible connecting pair - a threaded fitting and a coupling with an “American” union nut. The connection is reliable, and soldering such elements even in such difficult circumstances is no longer difficult.

• If at least some node during installation raises even the slightest doubt, without any regret it should be cut out and other parts welded in. Believe me, it will not take much time and will not entail serious costs. But if over time such a dubious area suddenly leaks, the consequences can be very sad.
• The next group of errors has already been mentioned above - this is a violation of the pipe soldering technology. This may include insufficient or excessive heating. The force applied to the parts when connecting should be in moderation. Too much compression will result in the formation of an internal "skirt". Equally dangerous is the insufficient application of force - the pipe does not enter the socket of the connecting part to the end, there remains a small area with an increased diameter and a thinner wall - a potential breakthrough!

• Do not forget about cleaning the parts to be welded from dirt and grease. Perhaps this seems insignificant, but in practice there are quite enough cases when such neglect subsequently turned into a weak connection and the formation of a leak.
• Attempts to change the position of the parts during the setting and cooling of the connection are very dangerous. Outwardly, this may not manifest itself, but microcracks appear in the connecting seam, which subsequently lead to accidents. If you don't like the connected node - "into the furnace" it, and make a new one, but don't try to change it!
• When stripping reinforced pipe not even a tiny piece of foil should remain on the cleaned area - this can become a potential site for a future leak.
• One more recommendation. It is clear that the material must be of high quality - you should not chase cheapness, since you can lose much more, especially since even branded polypropylene pipes and accessories for them are not so expensive. But there are cases when, during the installation of high-quality pipes, carried out with strict adherence to technology, the connecting nodes nevertheless began to fail over time. And the reason is simple - it was really used quality material but from different manufacturers. Seemingly insignificant differences in the chemical composition and physical and technical characteristics of polypropylene gave such an unexpected result - full-fledged diffusion of melts was not achieved.

Therefore, a final tip: use high-quality pipes from one manufacturer. It is probably clear that all components must also be of the same brand.

At the end of the publication - an informative video about the soldering of polypropylene pipes:

Video: the master shares the secrets of high-quality soldering of polypropylene pipes

Recently, traditional cast-iron and steel pipelines are increasingly being replaced by more modern products of the 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: the characteristics are suitable for hot water supply, as well as for the system central heating up to 95 degrees of heat, nominal pressure - 2.5 MPa

Step 1. The choice of one or another 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 amount necessary pipes and fittings, the room is measured and its 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. This will require special device- 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. Special attention you need to give 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 is useful when connecting pipes of 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 the 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 is the main problem in the arrangement of 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.