Repairs are quite expensive, so many people prefer to do it themselves to save money. But if wallpapering and laying linoleum are considered simple types repair, then laying or replacing communications requires certain skills and special equipment.
For example, many people are afraid of the need to connect plastic pipes when repairing a water supply system. In fact, there is nothing complicated about this, just 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 and 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),
- file and fine-grained sandpaper for smoothing out burrs on cut pipes,
- pipe welding machine.
You will also need alcohol to degrease the structural elements in the welding areas and rags.
What is a welding machine for plastic pipes?
The action of a welding machine for plastic pipes is to heat the ends of the pipe and fitting that 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 support platform and a body equipped with:
- temperature controller,
- light indicators of the operating status of the device,
- heating element (mirror, sole),
- handles for adjusting the position of the mirror.
In the base of the device there are two holes onto which nozzles are attached, corresponding to the diameters of the 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 reliably connect the pipeline elements without worrying that one of them is not warm enough.
There are 2 types of welding machines for plastic: sword-shaped and cylindrical. The xiphoid apparatus is sufficient for use in domestic conditions, but this instrument has one drawback - rather poor stability.
Installation work with a plastic pipeline involves cutting and connecting operations. Due to the technical properties of the material, such problems are easier to solve than in the case of metal pipes. But for the most part, only experienced craftsmen are familiar with the same cutting technologies, although it does not cause any particular difficulties. In essence, it requires soldering of the material, as a result of which it is possible to change the parameters of the structure or a separate segment of the pipeline.
Polypropylene? As with metal welding, you will need a special apparatus. It can be a small manual thermal cutter or a massive professional installation. But in both cases the operating principle is the same.
Soldering tool
There are specialized single-format and multifunctional pressing machines, through which soldering is carried out. In this case, this process can be considered both as a cutting method and as a joining operation. The device itself, in its simplest versions, is a small structure with electromechanical filling and equipment formed by metal clamps.
How to solder polypropylene using such a device? For the most part, the user is only required to correctly guide the workpiece in accordance with the requirements of the technical process. The operating principle of the equipment itself is to melt the pipe. The two parts heat up upon contact with metal surfaces, after which any joining operations can be performed with them. In other words, the compactor provides two technological functions. Firstly, this is the achievement of temperature effects for melting polypropylene, and secondly, clear positioning of the edges of the pipes for their correct alignment.
Preparing for work
The handling of materials is very delicate. In the molten state, plastic is very sensitive and susceptible, so foreign particles can easily penetrate into its structure, the presence of which in the future can negatively affect the strength qualities of the pipeline. Therefore, both the workpieces themselves and the cutting apparatus must be thoroughly cleaned, rinsed and dried.
Additional devices are also prepared that should be at hand during the operation. For example, the question of how to solder polypropylene in hard to reach places, often includes mention of special hooks and an LED flashlight. The hook will allow you to hang the device if you cannot get to the work site with your whole body and conveniently position the tool, and the flashlight will provide visibility if other light sources do not penetrate to the work site.
Stages of the operation
The complete soldering process includes 4 stages - cutting, heating, joining and cooling. Each stage requires special actions from the operator, which depend on the result that should be obtained.
Cutting is not done in every case, but it can be used to make a neat cut with the same precise subsequent connection. The advantages of thermal cutting over mechanical methods include eliminating the risk of deformation of integral parts of the workpiece.
How to solder polypropylene pipes to maintain their original shape? To do this, it is enough to correctly fix the pipe in the clamping rings - then the cutting plate will carefully carry out the cutting and final soldering. The final stage of aging is the most critical. When performing this, it is important to correctly secure the finished part of the pipe and allow it to cool exactly as much time as required by the standard.
Soldering technology
The soldering technique is worth considering separately. In a shortened form without cutting, this operation is performed more often, so most devices have a design optimized specifically for this task. So, the essence of the process is that the two ends of the pipe are installed on opposite sides in fixing rings.
Polypropylene? Unlike a welding machine for metal, soldering irons for plastic form a seam without user intervention. Maximum interventions include manual models, in which the user simply presses a lever that brings two pipes together. This is done smoothly and without unnecessary pressure - the soft molten plastic should mix, forming a single structural mass at the connection point.
Industrial soldering irons for plastic
Complex and important activities may require the help of professional plastic soldering equipment. Such models are distinguished by the ability to work with large diameter pipes, as well as high heating intensity. Accordingly, such units are superior to manual models both in size and in electric motor power. At the same time, you should not consider an industrial soldering iron as a universal one. It is designed specifically for medium and large sizes, but is not suitable for small diameters.
How to solder polypropylene onto industrial equipment? The technology and operating principles are generally the same, but each operation is performed on a separate modular station. One modular unit prepares the pipe with countersinking and trimming, another directly cuts the plastic, the third provides heating, and the fourth is responsible for positioning the workpiece.
Soldering parameters
It has already been said that the quality of the result will depend on how correctly and accurately the last stage of cooling was performed. The complexity of this stage lies in the fact that it is necessary to observe the exposure time regime at several stages. Usually there are two stages - during the heating process and during final hardening. Time intervals depend on the thickness of the pipe. Another factor due to temperature conditions is also taken into account.
At what temperature should polypropylene be soldered? Standard manual devices operate at 250-270 °C. This is enough to bring an ordinary household plastic pipe to the required condition within 15 minutes. As for the relationship between diameter and cooling time, the minimum standard size of 12 mm will require 4 seconds of waiting for direct connection, and 120 seconds for final curing.
The maximum pipe diameter of 50 mm for hand soldering irons requires a 6-second wait when soldering, and hardening occurs after 240 seconds.
Features of soldering in hard-to-reach corners
Working in hard-to-reach and complex areas requires not only the use of auxiliary equipment (as already mentioned, flashlights and devices for holding a soldering iron). Corner connections also provide for a special implementation of the technology itself using special consumables. But first of all, it is important to remember that cutting is carried out only at right angles, and after cutting, the surfaces and ends of the ends must be degreased and cleaned with a soft abrasive.
Now we can move on to another question - how to calculate and solder angles. In this case, polypropylene is connected using additional nozzles, which makes adjustments to the waiting period for soldering. That is, to form an angle you will need a fitting or adapter made of the same polypropylene. This addition also increases the time for singing the connection section. With a minimum pipe diameter of 12 mm, this interval will be 5-6 s, and when working with a 50 mm workpiece, it will be about 20 s.
Is it possible to solder metal-plastic pipes with polypropylene?
Operations during which dissimilar pipes are combined are considered undesirable. Such designs are initially inferior to homogeneous analogues in reliability, however, there are cases when traditional metal-plastic must be introduced into a pipeline with polypropylene. Threading will not help in such situations, so you will have to resort to soldering. However, this connection will only act as an auxiliary tool.
Installation is carried out using a flange into which the ends of two pipes made of different materials. Soldering is needed just to prepare for such integration. To do this, using a soldering iron, the end of the plastic pipe is heated, the same fitting is put on it, after which you can begin connecting to the metal-plastic circuit through the flange.
Soldering errors
Errors mostly relate to violations in soldering technique and the choice of inappropriate materials. A common technology violation is deviation from the specified position when connecting pipes. Deviation from a straight line by a millimeter already means that the connection will be of poor quality.
How to solder polypropylene pipes correctly so that the position of the workpieces is not disrupted? In this sense, hand-held devices are the most problematic, since the lightness of the design does not contribute to protection from vibrations of the working equipment. Additional securing of the device using heavy devices will minimize the risk of deviation.
Conclusion
Theoretically, the method of joining plastic pipes through thermal action is flawless. Its main advantage is that interference in the structure of the material itself does not entail a reduction in its operational properties. The resulting seam has a uniform structure and will not be a weak point in the contour. The imperfection of this method depends on the practice of application. Therefore, the question arises as to how to solder polypropylene in order to achieve optimal results.
The success of the operation essentially depends on two factors. Firstly, on the quality of the technical organization of the work process - on the choice of materials, model of the device, consumables, etc. Secondly, on the experience of the operator himself. The user of the soldering iron must quickly manage the workpieces, observing both time intervals and the accuracy of pipe positioning.
A very common job when renovating a house is replacing old pipes that have served for more than half a century. Gone are the days when you had to call a plumber to install metal pipes. Today, cast iron and steel pipes have confidently replaced them on the market, which have many advantages over older pipe types.
If steel pipes were mainly connected by welding, today polypropylene pipes are connected using couplings. If the job is unsuccessful, the coupling can be disassembled and the defect eliminated.
So what are the advantages of polypropylene pipes? First of all, it is highly resistant to aggressive environments. Polypropylene pipes can withstand high temperature loads and pressure. The service life of polypropylene is half a century. Even a beginner can install pipes.
Installation of polypropylene pipes in the wall (example)
Now let's talk about the tool that is used in work when connecting polypropylene pipes.
- Directly polypropylene pipes.
- Several couplings.
- Angles at 90 and 45 degrees.
- Adapters with metal pipes to plastic ones.
- Pipe fastenings.
- Scissors for cutting polypropylene pipes.
- Soldering device.
- Merylon insulation.
- Tape measure, square and pencil.
Before you start work, you need to choose the right polypropylene pipes. Experts recommend buying the same pipe diameter as before. Then there will be no problems when switching from a metal piece of pipe to a plastic pipe.
How to properly solder polypropylene pipes for heating
Today, polypropylene pipes are connected using diffusion welding. Various angles, adapters and couplings are used. If the pipes are used for cold water supply, then you can safely expect that the pipes will be installed for fifty years. However, in the case of installation of polypropylene pipes for a heating system, the situation is somewhat different. Here important factor The factors that determine the service life of pipes are temperature and pressure. Despite the fact that polypropylene pipes themselves are very durable, they can lose up to seven years of their life due to high coolant temperature and pressure.
It must be said that it is unlikely to be present in home systems high blood pressure and temperature. Even if these figures increase sharply, polypropylene pipes will be ready for this.
There are a large number of colors of polypropylene pipes on the market. This is another advantage of the product over steel pipes, which must be painted after installation. Polypropylene pipes will already have a finished color.
It is worth noting that the assembled polypropylene heating system cannot be further disassembled. Using polypropylene pipes, the system is routed from the boiler and the coolant is supplied to the radiators. The service life of the pipes allows for hidden and exposed systems. This means that the pipes can be hidden in the wall if necessary.
To solder pipes yourself, you need to become familiar with basic work skills. Initially, it seems that the work is quite simple and will take a minimum of time. To some extent this is true. But here you need to be precise and careful. Before you start working with a soldering iron, you need to carefully read the instructions.
The instructions contain step-by-step instructions for the correct execution of the work. In addition, in the instructions you can find information about working with a certain type of polypropylene pipes. So there shouldn't be any questions.
Before you start assembling a heating system, you need to prepare a work plan, which includes a diagram. It indicates the places where wiring, taps, and plumbing fixtures will be performed. Once each part of the system is at hand, you can begin to assemble it.
Execution of work
The diffusion soldering iron must be placed on a special stand. As a rule, they are included with the device. When soldering, you need to hold the device and the parts to be connected horizontally.
It is much more difficult to solder pipes in a vertical position. It will be difficult even for a master to complete the work independently without an assistant. One person should hold the soldering iron, and the other should hold the pipes, which will need to be joined after heating. If the pipe diameter is more than 65 millimeters, then the work is even more complicated by the fact that it is necessary to use a socket.
Video: how to solder polypropylene pipes
Working with a machine for welding polypropylene pipes
Fusiotherm is the most common welding machine for polypropylene pipes. How to work with him?
Even before turning it on, you need to put attachments on the cold parts of the device, which are presented in the form of a mandrel and a coupling. Polypropylene melts at a temperature of 260 degrees. This is the temperature that needs to be set on the device. As soon as it heats up, the indicator will light up.
Pipes with a diameter of up to 40 millimeters are soldered using the socket soldering method. We use a centering device and attachments for the device. While the device is warming up, you can cut the pipes to the required length with special scissors. If there is reinforcement in the pipe, then using special tools it must be removed at the soldering site. Otherwise, the connection will not be of good quality.
It is very important to wear gloves to avoid thermal burns from hot polypropylene or a welding machine. As soon as the ends of the pipes heat up, you need to immediately join them before the deformation passes. Until the welding elements are dry, they cannot be loaded.
Some nuances
After the pipes are connected, they must be secured in certain areas. When the heating system heats up, the pipes will begin to expand. If there are no fastenings, the pipes will begin to sag. For heating systems, it is best to use reinforced pipes. They consist of two layers of polypropylene, between which an aluminum layer is placed. It allows you to limit the linear expansion of pipes when heated.
After all the work has been completed, you need to visually inspect the joints and transitions for flaws. If any are found, you need to redo the work.
Today, it will not be a problem to find in the market or a specialized store all the necessary parts for high-quality implementation of a heating system made from polypropylene pipes with your own hands. It is worth noting that polypropylene is much cheaper and more practical than steel or cast iron pipes.
The key to successful and high-quality work lies in the correctness and accuracy of all work. Beginners are advised to try welding using two separate pieces of pipe as an example. It may not work out the first time, as a certain “grip” is required.
If you are not confident that you will be able to complete the work yourself, then it is better to entrust it to specialists who have experience and the right tool. Remember that a heating system requires quality that will last for many years. After all, a lot of money is spent on its implementation. It is unacceptable to lose material and money due to improper execution of work.
When installing new polypropylene pipes to replace outdated metal systems, a situation may arise when connecting pipes by welding must be performed in places that do not quite meet the conditions for such an operation.
Therefore, to independently update the pipeline, certain knowledge is required to help organize the welding of polypropylene pipes in an inconvenient place, using auxiliary tools for this.
Tools for work
A special soldering iron for polypropylene pipes and a set of Teflon nozzles help to make a high-quality connection of pipe elements. Using a soldering iron, you can special effort make a welding connection on any section of the pipe. Using nozzles, you can connect pipe elements of different diameters.
In addition, soldering polypropylene pipes in hard-to-reach places requires the following tools:
- A device for cutting polypropylene pipes (most often the cutter comes complete with a soldering iron).
- A solution that allows you to degrease the soldering area.
- Set of connecting elements.
You also need to prepare a tape measure, ruler and pencil, as well as a corner and a knife. In some cases, a rag may be needed.
Methods for welding polypropylene pipes
Soldering pipes in hard-to-reach places can be done in different ways depending on the working diameter of the pipes:
- The butt welding method is used to connect pipes with a wall thickness of at least 4 mm and a diameter of up to 50 mm. In everyday life this method is used quite rarely.
- The socket method is used when connecting pipes with a diameter of up to 40 mm. The operation requires a special welding mechanism equipped with a centering device.
- When saddle brazing, a special bell-shaped saddle is welded to the pipe at an angle of 90 0 using a butt joint. The saddle is drilled and a piece of pipe is welded to the connection point, resulting in a T-shaped adapter at the outlet.
Welding in hard-to-reach places
Soldering hard-to-reach areas of polypropylene products is much more difficult than straight runs. To create favorable conditions Working in such places requires a sufficient amount of effort.
“Inconvenient” places include:
- Space under the ceiling.
- Corners of the room.
- Cramped conditions for placing a soldering iron.
When welding polypropylene pipes in hard-to-reach places under the ceiling, you need to prepare a place where the welding machine will be placed when manually forming the connection. For this purpose, you can invite an assistant or hang the device on a special hook prepared in advance.
If the pipes are located very close to the wall, a special technique is used: the direct and mating parts of the joint being formed are alternately heated with a soldering iron. In this case, the heating must reach such limits that the first heated section does not have time to cool down while the counter part is heating up.
Features of soldering in corners
To solve the problem of how to solder polypropylene pipes in hard-to-reach places, for example, in corners, you need to know the features of such connections. The joining of pipe elements in the corners of the room is carried out using blanks cut at an angle of 90 0. It is important that their ends are thoroughly cleaned and treated with degreasing agents. The use of special corner adapters and fittings contributes to the formation of smooth transitions on pipe elements during corner connections.
The formation of corner joints on pipes located at a short distance from the wall is also performed by sequentially heating the straight and mating parts. In this case, special attention should be paid to the depth of insertion of the pipe element into the body of the corner piece. To ensure high precision it is necessary to make the appropriate mark with a marker or pencil.
Deciding on how to solder polypropylene pipes in hard-to-reach places requires careful attention and precise execution of all actions. Docking elements that have even a slight defect must be replaced with new parts. According to experts, when making connections in hard-to-reach places, you should not turn off the power to the welding machine; it is better if it is always on.
Soldering polypropylene pipes in hard-to-reach places: how to solder, rules and welding methods
Soldering polypropylene pipes in hard-to-reach places: how to solder, rules and welding methods
We solder polypropylene pipes in hard-to-reach places
– the process is technically simple, but requires precision and compliance with increased safety measures. Otherwise, the service life of the polymer system can be reduced several times.
Sequence of soldering polypropylene pipes
How to solder pipes in hard-to-reach places
When welding assemblies and connecting elements in hard-to-reach places, always start with the most difficult section. For soldering in the most difficult areas, use American.
To do this, you will need basic tools for soldering PPR (polypropylene) pipes:
- a welding machine (iron or soldering iron) with attachments of various diameters (electric coupling or rod apparatus);
- special scissors (pipe cutter). You can also cut the pipes with a grinder/hacksaw, but be sure to clean the edges afterwards;
- trimmer or stripper/shaver (cannot be used with fiberglass reinforced pipe).
During the installation process you will also need screw keys, a hammer drill, an angle grinder and other tools.
Please note that, regardless of the “soldering iron” used, the technology involves connecting pipes through elements:
Electrofusion soldering technology
Electrofusion is the most common soldering device. The “iron” is easy to use, but has its own technology:
- When connecting the welding machine to the power supply, make sure that you have enough space for “maneuvers” - nothing should get in the way. Plus, the environment in which you carry out work should not be lower than +10 ℃, otherwise you will not have time to capture the elements efficiently.
- The “soldering iron” must be placed on a hard surface, away from flammable objects.
- First, it is recommended to weld large chains/pipe assemblies that can actually be mounted into the walls, and then solder the remaining connections on the fly. To distribute the action plan, make a drawing.
- Check whether the coupling and pipe fit together before heating. If yes, then there will be no proper connection, and this place will leak. Therefore, the elements should be replaced. To avoid inconsistencies, it is necessary to select pipes and connectors from the same manufacturer.
- You can cut the pipe to the required length using special scissors, but it is more convenient to cut a reinforced pipe with a grinder. The cut must be made at an exact 90 degree angle.
- Clean the surface of the pipe to remove any unevenness.
- Place the desired attachment on the device. Nozzles are determined according to the diameter of polypropylene pipes.
- Set the iron temperature to 260℃. This parameter on expensive soldering machines is determined automatically by the device itself, but only after specifying the diameter of the PPR pipe. When the soldering iron is completely heated, the signal light will light up. Cheaper appliances heat up in about 15 minutes.
- We put the fitting and pipe on the nozzle. According to the book manual, this is done one by one, but in practice it is difficult to do. Therefore, it is better to put them on at the same time. For convenience, you need to kneel down and hold the “iron” between your legs.
- It is necessary to heat the fitting and pipe depending on the diameter of the material:
- 16 and 20 – 5 sec;
- 25 and 32 – 8 sec;
- 40 – 12 sec.
- The PPR pipe must be inserted into the nozzle all the way. If you are not sure, you can mark with a pencil how far it should go onto the pipe.
- Do not twist or turn the elements while heating - the soldering will be poor quality. But small (very minor) turns are acceptable.
- After heating, the pipe is removed, and then the fitting. The elements are connected and fixed within 20 seconds (motionless!). After removal from the device, you have no more than 5 seconds to make connections; after this time, the soldering may be of poor quality.
- If you have to weld three or more elements fixed in pipeline system(for example, you need to cut an already installed pipe and insert a fitting tap):
- it is necessary to cut the pipe, having previously marked the cut points;
- clean the elements and wipe with a degreaser/dry cloth;
- check that the tap does not interfere with closing/opening;
- first we solder the fitting and pipe on one side (right);
- moving on to soldering the chain on the other side, you must first heat the tap (and 5 seconds longer), and then heat the pipe (3-4 seconds less);
- we connect the elements;
- since the chain is suspended, for the convenience of heating the fitting, we press on the “iron” with improvised materials (for example, scissors).
- You can fix PPR pipes horizontally using clips, and vertically using a pipe clamp.
Please note that if overheated, the passage holes of polypropylene pipes and fittings will melt, and if underheated, the elements will not connect properly and will leak.
Rod machine for welding polypropylene pipes
The rod welding machine is used primarily for hard-to-reach places, as well as for damaged (drilled) pipes. The device has a more convenient design for direct work at any angle and on weight.
Manufacturers have developed a special repair kit for drilling holes in PPR pipes. It includes repair polypropylene rods and special attachments. In case of damage of this type, you must:
- Place a special attachment on the “soldering iron” (standard for repairing pipes of all diameters).
- Turn on the device and warm up to 260 ℃.
- The drilled hole in the pipe must be expanded with a drill with a diameter of 10 mm.
- Clean the surface from burrs and welded parts.
- Mark on the repair rod the depth to which it will be inserted into the pipe being repaired. Elements should not be joined.
- Clean the surface of the pipe being repaired with a degreaser or alcohol and let it dry for a few minutes.
- Using the nozzle, heat the surfaces of the pipe being repaired and the inserted rod simultaneously for 5 seconds.
- Without turning, connect the elements together and remove the rest of the rod.
The method of soldering with a rod apparatus under standard conditions does not differ from welding using other analogues.
Welding and installation of a separate part of the pipeline system
When installing a separate part of the pipeline (node/main):
- measure and cut the required pipe size;
- weld the chain on a fixed surface, and then install it in the planned area. That is, we first solder the assembly, and then connect it suspended with other sections;
- in the most difficult to reach places, use American ones.
Soldering the knot on weight
We solder pipes by weight:
- determine which side is the most difficult for weight soldering and start with it;
- Initially, the pipe and the connecting element/assembly are welded on one side according to standard measurements, observing set time for soldering;
- then (on the other hand) the connecting element heats up first, for a couple of seconds longer, and after that the pipe heats up a couple of seconds less than usual (in essence, you give time to the connecting element to warm up the pipe).
It is difficult to solder parts by weight, so to warm up it is recommended to press on the elements with improvised means (special scissors, etc.). It is better to invite an assistant for weight soldering.
Installation of the soldered assembly
First of all, the required assembly is welded on a hard surface. When it is ready, we proceed to the connection with the already installed pipes:
- Mark the cut areas on the working highway with a pencil. There is no need to cut out an area for the entire fitting or other connecting element. It is necessary to take into account that pipes will be inserted into it (for example, a tap measuring 10 cm, the holes for connecting to the pipes take up 4 cm in total, then you need to cut 6 cm of pipe);
- cut installed pipes on both sides with special scissors;
- clean the pipes with a degreaser and dry them from water;
- clean the elements;
- start welding the assembly. Start from a more difficult place.
Soldering a unit with other pipeline circuits is difficult, so you won’t be able to do it without help.
Before direct installation, it is necessary to prepare the grooves. This is done using a concrete circle mounted on a grinder or other tools. Mark the surface where the grooves will be. The cuts are made to a depth of about 2-3 cm (consider the diameter of the pipe) and are knocked out with a hammer, chisel, hammer drill, etc.
- Weld the required assembly outside the groove, and then mount it into the holes.
- To prevent damage, PPR pipes can be wrapped in construction tape, but for complete protection, a shell/insulation made of polyethylene foam is recommended.
- When moving from metal components, use a transition coupling or American for connection.
- To prevent the line from moving when the pipes expand, secure it with special elbow structures ( metal surface with clamps). The part is first attached to the wall surface and screwed with nuts, and then fixed with the pipeline.
- Secure the pipes with clips or a pipe clamp, especially in the most insecure places.
- Seal the holes.
Do-it-yourself installation of polypropylene pipes in hard-to-reach places
American adapter coupling
To connect nodes made of polypropylene, especially in difficult places, “American” is predominantly used (especially angular). This coupling easily connects the required pipe sections when the chains are already installed in the common pipeline. Plus, the area with this part can be often disassembled and reassembled.
An “American” profile is a joining of two sections of a pipeline or a transition to a pipe of a different size in diameter. On the one hand, the part is screwed/soldered/welded, and on the other, there is a dismountable American connection (in other words, a quick-release threaded nut).
The part is designed for joining PPR pipes and is used to supply cold or hot water. The coupling can withstand a pressure of 25 atmospheres and a temperature of 95 ℃ (depending on the model, it can be smaller or larger), and is also produced in different diameters (the larger, the higher the weight and price of the part).
The following types of “Americans” are chosen for connection:
- with internal thread;
- with external thread;
- coupling with external and internal thread.
According to the type of design, the American coupling is:
By type of threaded joints:
- flat (cylindrical);
- conical (creates the highest quality connection).
The most popular for installation in hard-to-reach areas are the American corner ones.
Installation of PPR pipes using an American coupling
When installing an “American” with a metal assembly, gaskets/seals are required:
- polyurethane;
- paronite;
- rubber;
- Teflon thread or paste, etc.
Plus, to tighten the coupling during installation, you need a hexagon, a tension wrench (regular or with a tape) or a cylinder with recesses for hooks.
Coupling installation methods:
- “American” for PPR is welded/soldered. The connection method is standard - “soldering iron”.
- Tightened with a tool on the metal part. When tightening, seals are used.
Video tutorial on pipe installation using a transition coupling
Installation or repair of polypropylene pipes is not very difficult to work with. The main thing is to stick temperature regime during heating and the time of joining of elements. Plus, when repairing, you need to start from more difficult-to-reach places. Do not forget to also secure the line with clips or other parts so that the pipeline does not rupture when the pressure increases.
Do-it-yourself soldering of polypropylene pipes: video, welding in hard-to-reach places
Soldering polypropylene pipes with your own hands is a technically simple process, but it requires precision and compliance with increased safety measures. Otherwise, the service life of the polymer system can be reduced several times.
Recently, traditional cast iron and steel pipelines are increasingly being replaced by more modern products of the chemical industry - polyvinyl chloride and polypropylene pipes. But new materials require a different technology for connecting pipes, and the most effective in this case is soldering.
Soldering polypropylene pipes with your own hands
Pay attention! The soldering temperature, which affects the quality of the connection, depends on the size of the products - this can be seen in the table below.
Stage 1. Selection of propylene pipes
Step 1. The choice of one or another source material directly depends on the future purpose. The main criterion for division is the maximum permissible temperature working environment. In this regard, pipes are allocated for hot, cold, and mixed water supply.
Fittings for polypropylene pipes
To determine exact quantity necessary pipes and fittings, the room is measured and a rough plan is drawn up. The latter indicates the dimensions of the future highway and all its elements.
After purchasing all the components, you can proceed to the next stage.
Stage 2. Necessary equipment
The principle of soldering is to heat the ends of the connected pipes to the required temperature and then fix them. To do this you will need a special device - a welding machine.
It can be of three types:
- With manual control– used for pipes ø1-2.5 cm; different products require different nozzles;
- semi-automatic devices;
- automatic models.
Design of a soldering iron for polypropylene pipes with a cylinder-shaped platform
Soldering iron for polypropylene pipes
In addition to the device itself, the work will require:
Scissors for cutting polypropylene pipes
Stripping for polypropylene pipes
About choosing nozzles
Soldering iron attachments for soldering plastic pipes
Heating nozzles must match the cross-section of the pipes being connected. To do this, you need to pay attention to certain parameters:
- strength;
- maintaining shape during temperature changes;
- thermal conductivity.
Most welding machines are compatible with several different attachments at once, which is extremely convenient when arranging complex pipelines.
Each nozzle has two ends at once - one is intended for heating the outer surface of the products, the other for the inner. All nozzles are coated with Teflon coating, which prevents the sticking of molten coating. The sizes of the nozzles range between 2 cm and 6 cm, which completely coincides with the common pipe sections.
Soldering polypropylene pipes with your own hands
Soldering polypropylene pipes with your own hands
When the plan has been drawn up and all the components have been purchased, all that remains is to thoroughly clean the room. Particular attention should be paid to dust, because even the smallest particles, settling on the seams, can easily break the seal.
Depth mark
First, the nozzle is inserted into the socket, after which the device is turned on. Next steps 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 being connected mutually penetrates each other, and after cooling, forms a monolithic element. One of the most common processing methods, which, however, is acceptable only for homogeneous materials.
Pay attention! In this case, the soldering temperature reaches 265ᵒC. It is at this temperature that polypropylene melts.
Video - Diffusion soldering of PP pipes
Method No. 2. Socket soldering
When welding with the socket method, welding machines with different sections of nozzles are used. The procedure itself looks quite simple.
Step 1. First, pipe sections of the required length are cut. It is important that pruning takes place exclusively at right angles.
Step 2. The ends of the products are cleaned with a shaver (if reinforced pipes are used).
The ends of the products are cleaned with a shaver
Step 3. The ends are inserted into a nozzle of the appropriate cross-section, heated to the melting temperature and connected.
Pay attention! It is extremely important that the pipes do not change their position when cooling.
Method No. 3. Butt soldering
Industrial machine for butt welding of plastic pipes
This method is suitable for connecting large diameter pipes. As in previous options, the pipes are cut into sections of the required length, and the ends are carefully cleaned.
Method No. 3. Sleeve soldering
With the coupling welding method, an additional part is introduced between the elements being connected - a coupling. Warming up occurs in the same way, only it is not the sections of the highway that are heated, but only the connection elements.
Method number 4. Polyfusion soldering
A type of diffuse technology, characterized in that only one of the two elements being connected melts.
Method No. 5. Cold soldering of PP pipes
Cold soldering of PP pipes
This welding method involves applying a special adhesive composition to the pipes being connected. It is characteristic that the use of “cold” welding is permissible only in those lines in which the pressure of the working fluid is insignificant.
Apply glue to both cuts " Cold welding"and press the edges tightly together, holding for 15 seconds.
Quality control
When overheating or connecting small-diameter pipes, there is a risk of sagging on the inner surface. These sagging 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 joint needs to be blown out, and if the air flows freely, then the welding definitely turned out to be of very high quality.
Soldering polypropylene pipes
Pay attention! After this, it is necessary to check the tightness of the connection - to do this, a small amount of water is passed through the soldered elements.
Important rules for soldering polypropylene
For a high-quality and tight connection, it is necessary to adhere to certain rules.
- The device must always be in working order. In this case, it will take a maximum of five minutes to weld a new section.
- When the plastic hardens, the connected elements must be motionless. The best option There will be mechanical fixation, for example, a clamp. If the seam is subjected to even the slightest impact, the tightness will already be broken.
- Both elements must heat up at the same time.
Both elements must heat up at the same time
Soldering of PP pipes in difficult areas
When asked which main problem When installing 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 inconvenient large area is installed. It is advisable to form it separately, and only then install it in a permanent place.
PP pipes for water supply
After fixing the problem area, smaller and therefore easier to install elements are installed. This event needs to be carried out by at least two people.
Typical mistakes when soldering plastic pipes
- Poor quality parts. If defective pipes or connecting couplings are noticed (with cracks, dirt, broken geometry), then they need to be replaced, as they will cause a poor-quality connection.
- Use of components from different manufacturers. Each company operates with its own standards and regulations, so its pipes are suitable exclusively for its fittings. Also, parts may differ in chemical composition. All this has direct influence on the quality of welding, for this reason all components must be purchased from the same brand.
- Overheating of parts. This error can be seen with the naked eye - the pipe softens and it will not be possible to install it into the coupling without deformation.
- The welding machine heats up poorly. In this case, a reliable connection is also unlikely to be possible. Perhaps the pipeline will function normally at first, but sooner or later a leak will occur. To avoid this, you need to give the device five to ten minutes to heat up, and do not unplug it during operation.
- Used fittings. As already noted, if the fitting is loose, it should be removed. It must not be reused.
Pipe fastener with clamp
Pipe fastener with clamp
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 that expensive; at least autonomy from plumbers costs more.
Soldering polypropylene pipes with your own hands - step by step instructions!
Find out how to solder polypropylene pipes with your own hands! Methods for soldering PP pipes, step-by-step instructions, photos + video.
Any modern housing, be it a private mansion or a 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 a heating system. Few people are now attracted by the labor-intensive and rather complex 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, thread cutting, etc. Plus, a special approach is required to “packing” each threaded connection so that the connecting unit turns out to be of high quality, without leaks.
It's good that modern technologies allow you to avoid all this hassle by using polypropylene pipes. At making the right choice materials and high-quality installation, plumbing and heating circuits are practically in no way inferior to steel ones, and in many respects they are far superior to them. In addition, the soldering of polypropylene pipes itself is not so complicated; instructions for its implementation will be discussed in this publication.
Not all polypropylene pipes are the same
Before you start considering 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. Choosing pipes based on the principles of “which ones are cheaper” or “which ones were available” is completely unacceptable. The consequences for an unscrupulous home craftsman can be very sad - from deformation of the laid pipeline to its rupture or the appearance of leaks in connecting nodes.
There is no need to explain the difference in diameter - different systems and their different sections use their own dimensions, which are predetermined by hydraulic calculations. The range of diameters, from 16 to 110 mm, allows you to almost completely provide everything possible options. Moreover, practice shows that for a house or apartment, an assortment of up to 40 mm is usually sufficient, much less often - up to 50 ÷ 63 mm. Larger diameter pipes are, rather, main pipes, and they have specific installation features, but face it home handyman- it’s unlikely that you’ll have to.
The difference in color between some types of pipes may immediately be apparent. This is what you can pay the least attention to - white, green, grayish and other walls - they don’t say anything. Apparently, this is simply a decision by manufacturers to somehow distinguish their products from the general background. By the way, for heating circuits, white color will definitely be preferable, since the pipeline will unobtrusively fit into any interior without creating a disharmonious color “spot”.
But colored stripes, if they exist, already carry an informative load that is intuitively understandable to everyone. Blue stripe– the pipe is designed exclusively for cold water supply, the red one is capable of withstanding elevated temperatures. However, such color marking (which, by the way, very often does not exist at all) is only very approximate and does not fully reveal the operational capabilities of a particular pipe. It helps you simply not to make mistakes 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 provided by alphanumeric markings, which are usually printed on the outer wall. This is where it’s worth being more careful.
The international abbreviation for polypropylene is PPR. There are several types 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 permissible 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 at length about each of them, you can give a plate that characterizes the operational capabilities and scope of application of the 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 water-heated floor circuits, with a maximum operating coolant temperature of up to 45 °C. The material is the most affordable - due to its not particularly outstanding physical, technical and operational parameters. |
| PN-16 | 1.6 | 16.3 | The most popular option for autonomous cold and hot water supply systems, with an operating temperature of no more than 60˚C, a pressure of no higher than 1.6 MPa. |
| PN-20 | 2.0 | 20.4 | Cold and hot autonomous or central water supply. Can be used in autonomous heating systems, where water hammer is guaranteed to be absent. The coolant temperature should not exceed 80 ˚С. |
| PN-25 | 2.5 | 25.5 | Hot centralized water supply, heating systems with coolant temperatures up to 90÷95˚С, including central ones. The most durable, but also the most expensive type of pipe. |
Of course, in order for a 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 of various types is 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 - very significant linear expansion when heated. If for cold pipelines located inside a building this is not so significant, then for hot water supply pipes or heating circuits this feature can lead to sagging, sagging of long sections, deformation of complex junctions, and the occurrence of internal stresses in the body of the pipe, shortening 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 in any way affect the soldering technology.
But with aluminum it’s 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 (in the illustration - bottom left). Another option is that the reinforcing belt runs approximately in the center of the wall. For each type of such reinforcement, there are special technological installation nuances, which will be discussed below.
Both fiberglass and aluminum reinforcement significantly reduce the thermal linear expansion of polypropylene pipes. In addition, the aluminum layer performs another function: it becomes a barrier against oxygen diffusion - the penetration of oxygen molecules from the air through the walls of the pipe into the coolant.
The penetration of oxygen into the liquid coolant medium can cause a number of negative consequences, among which the main ones are increased gas formation and activation of corrosion processes, which is especially dangerous for metal parts of boiler equipment. The reinforcing layer can greatly reduce this effect, which is why such pipes are most often used specifically for heating circuits. IN water supply 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, glass fiber reinforced. | PPR-GF-PPR | 0.35 | 900 |
| Polypropylene, reinforced with aluminum. | 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 number.
2 – material of manufacture and structure of the pipe. In this case, it is single-layer polypropylene. Pipes with fiberglass reinforcement are usually marked PPR-FG-PPR, with aluminum - PPR-AL-PPR.
Reinforced pipes with an outer polypropylene layer and an inner wall made of cross-linked polyethylene can be found. 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 take part in it.
3 – standard pipe dimensional coefficient, equal to the ratio of the outer diameter to the wall thickness.
4 – nominal values of outer diameter and wall thickness.
5 – the type of pipe mentioned above according to the nominal operating pressure.
6 – 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 cuts in multiples of 1 meter.
Numerous components are available for sale for all pipes - threaded fittings, for transition to another type of pipe, with external or internal threads or with an American union nut, couplings, tees, diameter transitions, bends at 90 and 45 degree angles, plugs, bypass loops , compensators and other necessary parts. In addition, it is possible to purchase taps, valves, manifolds, and “oblique” coarse water filters designed for direct soldering into polypropylene pipework.
In a word, such diversity 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 reserve, at least in order to conduct a small training session before starting practical installation - so to speak, “get your hands on it.”
Methods for connecting polypropylene pipes
Polypropylene is a thermoplastic polymer - when heated, its structure begins to soften, and when two fragments uniformly heated to a certain temperature are connected, 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 high-quality connection - ensuring optimal heating and the required degree of compression, after reverse polymerization there should be no boundary as such - a completely monolithic assembly is obtained.
It is on this property that the main technological methods for joining polypropylene pipes are based - this method is often called polyfusion welding.
Such welding (soldering) can be carried out using a socket or butt method.
- Sleeve welding is precisely the technology that is most often used when installing water pipes or heating circuits in a house or apartment. It is designed for small and medium diameter pipes, 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, internal diameter which is slightly smaller than the outer diameter of the pipe. That is, in a normal, “cold” form, the parts cannot be paired. A coupling can be not only, excuse the tautology, the coupling itself, but also the installation section of a tee, bend, tap, threaded fitting and other components.
The principle of such welding is shown in the diagrams below.
The pipe (item 1) and the coupling or any other connecting element (item 2) are simultaneously placed on the heating elements of the welding machine.
A pair is pre-installed coaxially on the working heater itself required diameter, consisting of a metal coupling (item 4), into which the pipe will be inserted, and a mandrel (item 5), onto which the necessary connecting element is placed.
During the heating period, a belt of molten polypropylene of approximately the same width and depth is formed along the outer surface of the pipe and the inner coupling (item 6). It is important to choose the right heating time so that the melting process does not penetrate the entire pipe wall.
Both parts are simultaneously removed from the heater and coaxially, with force, connected to each other. The melted plastic outer layer of polypropylene will allow the pipe to fit tightly into the coupling all the way to the length of the heated section.
At this stage, the process of polyfusion, cooling and polymerization occurs. The result is a reliable connection, which, although shown in the diagram as a shaded area (item 7), in reality, if you look at the section, it is not visible at all - it is practically a monolithic wall.
- Butt welding is performed slightly 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 to ensure they fit perfectly together.
The pipes are pressed on both sides against a trimmer - a rotating disk (pos. 2) with precisely aligned knives (pos. 3)
The pipes are again pressed towards the center, and at the ends, over the entire wall thickness, areas of polypropylene melting are formed (item 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 this is only at first glance. With this welding technology, precise alignment of the mating parts is of decisive importance. In addition, when sleeve welding the required degree of compression of the mating molten sections is ensured to a greater extent by the difference in the diameters of the parts. In this case, a significant external force is required, directed strictly along the axis of the connected pipes. All these conditions can only be met when using a special, rather complex machine-type apparatus.
There are many machines for butt welding, but almost all of them have a powerful frame with guides and clamps for clamping pipes of various diameters - to ensure joint alignment, a removable or folding end cap 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 likelihood of encountering it at the household level is almost zero.
There is also a “cold” welding method - using glue based on a strong organic solvent. The point is that when treated with this composition, the surface layers of the polymer soften. The parts can be connected in the desired position at this time, and since solvents are usually highly volatile, they evaporate quickly. then the reverse polymerization process begins quite quickly.
This technology is more suitable for polyvinyl chloride (PVC) pipes that do not have proper thermoplasticity. In addition, this type of connection method has, perhaps, more disadvantages and limitations in use than advantages, so it is not in particular demand, especially since there is a simple and accessible technology for sleeve polyfusion welding.
What is required for installation work
So, in the future we will consider exclusively socket polyfusion welding (soldering). To cope with this task yourself, you need to prepare a number of tools and accessories.
- First of all, this is, of course, a machine for welding polypropylene pipes. Such a tool is not so expensive, and many zealous owners already have it in their home “arsenal”.
The welding machine must be supplied with coupling-mandrel kits of the required diameters. 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 different diameters without interruptions for replacement.
If you don’t have your own device, and circumstances currently do not allow you to purchase one, then many stores 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 welding machines are designed approximately the same and operate on a similar principle, but they also have certain differences in layout and functionality. Useful information for those who have decided to make such a purchase is posted in the article on our portal, specifically dedicated.
In the text you may find the definition of a pipe soldering machine - but this is just a “play on words”. There is no difference between these concepts in this case.
- To cut the pipe, special scissors are required. Moreover, they must be sharply sharpened, with a working ratchet mechanism that ensures a smooth cut. The blade should not be jagged or bent.
Of course, you can cut the pipe with a hacksaw, just a metal blade, or even a grinder, but this is absolutely not a professional approach, since the required accuracy and evenness of the cut cannot be achieved with such tools.
machine for welding polypropylene pipes
- It is necessary to prepare a marking tool - a tape measure, a ruler, a construction square, a marker or a pencil. To correctly place the pipes, you have to resort to a level.
- If you plan to solder polypropylene pipes with aluminum reinforcement, then additional tools are required.
- if the pipe has external reinforcement, then a shaver will be required to clean the aluminum layer at the weld penetration site.
- if the aluminum reinforced layer is located deep in the thickness of the wall, then the pipe still requires preliminary preparation, but in this case a trimmer is already used.
A trimmer is often similar in appearance to a shaver, but there is a difference between them - it lies in the arrangement of the knives. With a shaver, the cut goes tangentially parallel to the axis of the pipe, and with a trimmer, as even their names make clear, the knife processes the end and removes a small chamfer.
Read a useful article, and also familiarize yourself with the varieties and selection criteria on our portal.
We will dwell on this point in more detail when considering pipe soldering technology.
- Many people overlook this, but the welded sections of pipes and couplings must be cleaned of dirt, dust, moisture, and then degreased. This means you need to prepare a clean rag and an alcohol-containing solvent (for example, regular ethyl or isopropyl alcohol).
But you should not use solvents based on acetone, esters, or hydrocarbons, since polypropylene is not resistant to them, and the walls may melt
- It is also necessary to take care of protecting your hands. They will have to work in close proximity to the heating element of the device, and getting a serious burn is as easy as shelling pears.
Suede work gloves are best suited for this task - they practically do not restrict movement, will not begin to smolder from contact with a hot heater, and will reliably protect your hands.
And one more important warning. Majority installation work very often it can be carried out not locally, but, for example, on a workbench in a workshop - some devices even have special brackets with clamps 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 of a bathtub or toilet.
In any case, wherever soldering is carried out, it is necessary to provide highly effective ventilation. 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, it has been tested on “my own skin.” The author of these lines spent a day with a temperature of 39° after seven hours of work in a fairly spacious combined bathroom, with a ventilation vent that seemed to work well. Don't repeat the mistakes!
How to solder polypropylene pipes
General technological methods for welding polypropylene pipes
- First of all, a novice master must have a clear idea of what he is going to mount. A detailed diagram-drawing must be prepared, with dimensions and specific details indicated - this same “document” will become the basis for the purchase required quantity pipes and components.
- If conditions permit, for example, there is no finishing in the room where installation will take place, then it is best to transfer the diagram directly to the walls - it will be more clear and you can measure required lengths pipes literally in place.
The key to success is to try to complete the maximum possible number of knots in a comfortable working position, on a workbench. Working with a soldering machine directly on site, and even alone, without an assistant, is an extremely difficult task, and it is very easy to make an error. It is clear that such operations cannot be completely avoided, but their number should be reduced to the possible minimum.
- The soldering machine is getting ready for use. Working pairs - couplings and mandrels of the required diameters for operation - are put on its heater and tightened with a screw. If you plan to work with one type of pipe, then there is no need to be clever - put on one pair, as close as possible to the end of the heater.
There are welding machines with a cylindrical heating element - it has a slightly different fastening of the working elements, like a clamp. But figuring this out is not difficult.
- It will be much more convenient to work if the device is rigidly fixed to work surface workbench. It’s great if the design provides a clamp-type screw for fastening to the edge of the tabletop. But even with a conventional device 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 self-tapping screws.
Even with the stand fixed, the device can “wiggle” in it - there will definitely be some play. Here, too, you can provide your own fastening - drill a hole and screw in a self-tapping screw. When you need a soldering iron for remote work, removing this mount is a matter of a few seconds.
- The soldering iron is connected to the network. If it has temperature control, then it is set to approximately 260 °C - this is optimal temperature for working with polypropylene. You should not listen to anyone that for the 20th pipe you need 260 degrees, for the 25th – already 270, and so on - in increasing order. The temperature is the same, the heating time of the mating parts simply changes. In any case, those tables that the manufacturer provides in the product data sheet, and which will be posted below in this article, are designed for exactly this level of heating.
- Usually the soldering iron has a light indication. A lit red light indicates that the heating element is working. Green – the device has reached 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 prepared for work - the required piece of pipe is cut off, the connecting element is selected according to the installation diagram.
- Not many people do this, and yet the technology requires mandatory cleaning of the connection area from possible dirt and dust, and degreasing. In addition, even the slightest drops 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 risks leaking sooner or later.
- The next step is marking the connection. On the pipe it is necessary to measure from the end and mark the length of the penetration belt with a pencil (marker). It is up to this mark that the pipe will be inserted into the heating coupling, and 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 relevant relative position mating parts. For example, on one side of a pipe section a 90° bend has already been welded, and on the other side it is necessary to mount, say, a tee, 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 apply a mark across the border, along both sides.
There won’t be much time spent choosing the correct position during soldering, and such a “trick” will help 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 must go up to the mark made, the connecting element - all the way.
— After the pipe and connecting element are inserted completely, the warm-up time begins. Each diameter has its own optimal period, which should be followed.
— Once the time has expired, both parts are removed from the 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 force and bring it to the same mark. Light adjustments, without turning relative to the axis, are allowed only for one to two seconds.
— In this position, the parts must be held, without the slightest displacement, for deadline fixation.
— After this, the assembled unit should not experience any load during the established period of cooling and polymerization of polypropylene. And only then can it be considered ready
Now - about the main parameters that must be adhered to during installation. For ease of perception, they are summarized in a table:
| Name of indicators | Pipe diameter, mm | ||||||
|---|---|---|---|---|---|---|---|
| 16 | 20 | 25 | 32 | 40 | 50 | 63 | |
| Length of the pipe section to be welded, mm | 13 | 14 | 16 | 18 | 20 | 23 | 26 |
| Heating time, seconds | 5 | 5 | 7 | 8 | 12 | 12 | 24 |
| Time for rearrangement 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 unit, minutes | 2 | 2 | 2 | 4 | 4 | 4 | 6 |
| Notes: - If thin-walled PN10 type pipes are welded, 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 work is carried out outside or in a cold room at a temperature below +5°C, then the warm-up period is increased by 50%. |
|||||||
There is no question of reducing the set warm-up time (except for the case mentioned in the note to the table) - a high-quality connection will not work, and the unit will definitely leak over time. But regarding some slight increase, the masters do not have a unanimity of views. The motivation here is that pipes from different manufacturers may differ slightly in material, that is, harder or, conversely, soft polypropylene is found. But the masters have accumulated experience and precise knowledge of the material used, but for a beginner, the recommended indicators should still be taken as a basis.
Good advice - when buying pipes and components - take a small supply of the cheapest connecting elements and conduct an experiment - training. You can prepare a few pieces of pipe and perform test soldering.
With high-quality soldering, a neat collar about 1 mm high is created around the circumference of the connecting node, which will not interfere with the free passage of water. A neat collar will also be formed on the outside, which will not spoil appearance connections.
pipe cutters
But overheating can already lead to a defective connection. When the parts are combined, molten polypropylene begins to be pressed inward, where a “skirt” is formed and hardens, largely covering the passage. The water pressure in such a water supply system may be reduced, and in addition, such a defect often becomes a place for blockages to form over time.
Conducting such a practical lesson will help you accurately determine all soldering parameters and avoid mistakes.
Features of working with pipes with aluminum reinforcement
As mentioned above, there are two options here - the reinforcement layer is located near the surface of the pipe, or deep in the wall. Accordingly, the methods of preparing the pipe for welding also differ.
- It is clear that a layer of aluminum located near the surface simply will not allow for complete heating and connection of the assembly. In addition, such pipes always have a slightly higher diameter and simply will not fit into either the heating coupling or the connecting element. This means that it is necessary to peel 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 it - the installed knives carefully sequentially cut off the top polymer coating and the aluminum located underneath it.
Processing is carried out until the pipe stops at the bottom of the tool - the dimensions of the shaver are such that it will cut the foil exactly in the strip that is required for the welded joint for a given diameter, that is, you don’t even have to carry out the appropriate markings.
When soldering, the entire cleaned area must be heated and then completely inserted into the connecting piece. Leaving even a thin strip of protected pipe outside is prohibited.
- If aluminum foil is hidden in the back of the material, then it would seem that it does not allow for high-quality soldering. But there is already another nuance here.
If the pipe is not protected at the end, then water passing under pressure will try to delaminate it and find a way out between the aluminum layer and the outer polypropylene sheath. Aluminum, in addition, can begin to corrode and lose its strength. The result of such delamination first becomes “blisters” on the pipe body, which then inevitably end in a major accident.
The solution is to create conditions such that during welding the end of the pipe and the aluminum layer are completely covered with molten polypropylene. And this can be achieved by processing special tool, which was mentioned above - a trimmer.
Outwardly, it may be similar to a shaver, but its knives are located differently - they precisely align the end, cut a chamfer and remove a thin, about 1.5 - 2 mm from the edge, 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 stated, is best carried out on a comfortable, spacious work site, assembling ready-made water supply (heating circuit) units as much as possible, and only then installing and connecting them in place.
Working “next to the wall” is always more complex, time-consuming and nerve-wracking, since you have to hold a fairly heavy apparatus with one hand, while simultaneously providing heating to both mating parts. It is often almost impossible to make such a welded joint without an assistant. Therefore, it is worth reducing the number of such operations to a minimum.
But it is important to avoid mistakes. 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 distortion, insert it into the mandrel and coupling, after warming up, ensure progressive removal and then connection. It is necessary to foresee this point in advance - whether the available play is enough to perform all these manipulations.
- It happens that inexperienced craftsmen, having not foreseen this nuance, are faced with the fact that there is only one weld left, and there is no way to complete it. What to do?
The solution may be to weld a dismountable connecting pair into the cut pipe - a threaded fitting and a coupling with an American union nut. The connection turns out to be reliable, and soldering such elements even in such difficult circumstances is no longer difficult.
- If at least some component during installation raises even the slightest doubt, without any regret it should be cut out and other parts welded. Believe me, it won’t take much time and won’t entail serious expenses. But if, over time, such a questionable area suddenly leaks, the consequences can be very sad.
- The next group of errors has already been mentioned above - a violation of pipe soldering technology. This may include insufficient or excessive heating. The force applied to the parts during connection should be moderate. Compressing too hard will cause an inner “skirt” to form. No less dangerous is the insufficient application of force - the pipe does not fully enter the socket of the connecting part, there remains a small area with an increased diameter and a thinned wall - a potential place for a breakthrough!
- Do not forget to clean the welded parts from dirt and grease. This may seem unimportant, but in practice there are quite a few cases where such neglect subsequently resulted in a weak connection and the formation of a leak.
- It is very dangerous to try to change the position of parts during the setting and cooling of the connection. This may not appear outwardly, but microcracks appear in the connecting seam, which subsequently lead to accidents. If you don’t like the connected node, throw it away and make a new one, but don’t try to change it!
- When stripping a reinforced pipe, not even a tiny fragment of foil should remain in 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 a lot more, especially since even branded polypropylene pipes and components for them are not so expensive. But there are cases when, during the installation of high-quality pipes, carried out in strict compliance with the 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 diffusion of the melts was not achieved.
Therefore, one final piece of advice: use quality pipes one manufacturer. It’s probably clear that all components should also be of the same brand.
At the end of the publication, there is an educational video about soldering polypropylene pipes:
Video: a master shares the secrets of high-quality soldering of polypropylene pipes
