How to solder propylene pipes. Soldering technology for polypropylene pipes

Surely it will not be a secret to you that modern high-quality repairs with the replacement of a heating system or plumbing cannot be imagined without the use of polypropylene, i.e. plastic products. This material quickly appeared on the building materials market, revolutionized the water supply system and firmly took a leading position. In this article we will talk about how to solder polypropylene pipes with your own hands and how to save on calling specialists. This is a kind of instruction for carrying out work.

Advantages of the material

In the life of a modern person, plastic is used in almost all spheres of his life. They have become simply indispensable components for repairs and construction of any scale: for heating, water supply, sewerage, etc. All because similar pipes for utility networkshave undeniable advantages over other materials:

• Do not corrode;
• They are highly resistant to chemicals;
• Excellent resistance to various types of microorganisms;
• They have low sound and thermal conductivity;
• Lightweight for easy transportation;
• Environmentally friendly;
• Not difficult installation;
• Can be laid in both open and hidden ways;
• Long service life – with correct operation up to 50 years of service.

Please pay attention! Optimal mode work in which polypropylene pipes must be soldered with your own hands: working pressure up to 15 bar at a temperature of 0-10°C and up to 2 bar at high temperature up to 95°C.

It is thanks to its environmental properties that polypropylene is widely used in home water supply and heating. A wide selection of fittings with various types of chrome or brass inserts makes it possible to use them with existing parts of engineering structures or plumbing items.

Necessary equipment

Let's look at how to solder polypropylene pipes with your own hands. For the installation of heating or water supply lines, products are used that have outside diameter 16-63 mm. To connect them, a socket or, as it is also called, is used. socket welding. In order to solder you will need the following:

1. A soldering iron with a set of nozzles with different diameters. Well, how can you choose the appropriate soldering iron so that it is of high quality and allows for quick installation. The choice of tools is now really great, as are their price policy. A link to the selection rules will be after the article.

• The power of the tool plays a leading role. If you plan to use it at home to solder diameters 16-63 mm, then 1200 W will be enough for you. If you have to solder polypropylene pipes in hard to reach places and on professional level, then 1800 W or more will be required. But let’s say right away that a novice installer will not necessarily need such professional devices at home.
• The included nozzles act as heating elements. They consist of a sleeve, which melts the outer part of the product, and a mandrel, which melts the inner part of the socket of the connecting part. The nozzles must have a non-stick Teflon coating. Most often, a soldering iron kit comes with 6 nozzles of different diameters.
• The most convenient will be a soldering iron that allows you to install not one, but three nozzles. This design provides serious time savings, because you will spend much less of it in the process of replacing a nozzle of one size with another. After all, do not forget that to replace the nozzle you will need to cool it, replace it, and then warm it up again.
• A soldering iron that allows you to professionally solder products usually has electronic adjustment temperature. It allows you to control heating with an accuracy of 1-5°C. Of course, you can do without this adjustment and simply buy a thermometer to measure the temperature of the working part.

Please pay attention! When you work, the soldering temperature of polypropylene pipes must be observed. It is important not to exceed the operating temperature of the nozzle of 260°C, at which polypropylene can be soldered. Already at 270°C, the plastic will lose its stability, will stick too much, and will not fit into the fitting. But if the working part is underheated, polypropylene will not reach the required viscosity and, as a result, the necessary diffusion of the material will not occur. The consequence will be an unreliable connection.

2. The next tool that you will need when you decide to figure out how to properly solder polypropylene pipes will be plastic scissors.

3. In addition, you will need a pencil, tape measure, tarpaulin rags, and, of course, polypropylene pipelines and the necessary fittings.

What types of fittings are there?

To understand what can be soldered and how to solder different sections, you need to understand what additional connecting elements there are.

1. Solder couplings.
2. Angles 45° and 90°. Used for both different and the same sizes.
3. Tee or triple square.
4. Crosses.
5. Welded seat.
6. Plugs.
7. Soldering for polypropylene.
8. Transition having an external type of plastic thread DG.
9. Combined couplings (with external, internal thread or union nuts).
10. Combined tees (with external, internal threads or union nuts).
11. Combined angles (with external, internal thread or union nuts).
12. Combination angles for installation various types appliances (for example, mixer).
13. Ball valves, straight or angled with American type.
14. Walk-through water socket.

How to use a soldering iron

To understand how to solder polypropylene pipes, you need to understand the technology of the soldering iron. So, let's begin.

• The soldering iron must be placed on a flat surface. The nozzles are installed to the required diameter and tightened with special wrenches. A nozzle should be installed closer to the edge, which will be required in order to solder directly on the wall. It will be more convenient to assemble all separately located parts of the pipeline on a permanently located soldering iron, which you can do yourself. But you will need to assemble the parts into a chain on the wall with an assistant.
• Proper soldering should begin only after the tool has warmed up to operating temperature, approximately 10-15 minutes after it is turned on. Remember the nominal operating temperature in order to carry out soldering efficiently.
• The soldering iron must not be unplugged during the entire operation, i.e. while you solder everything.
• Two parts need to be heated at the same time.
• The plastic remaining on the nozzles must be removed with a tarpaulin rag after installing each fragment. It is not allowed to clean cooled attachments.

Soldering technology for polypropylene pipes

1. Using special scissors, cut the desired piece perpendicular to the axis.

2. Select the required fitting size. Please note here that the unheated fitting must have an internal diameter that will be slightly smaller than the outer diameter of the pipeline.

3. Clean the end of the pipe and the socket of the fitting from dirt, degrease it with alcohol or soapy water and dry it.

4. Place the parts to be connected on the corresponding nozzle on the soldering iron. The product must be inserted to the full welding depth into the sleeve, and the fitting socket must be placed on the mandrel.

5. After placing the parts in the nozzles, it is necessary to maintain the heating time. Here you need to act in accordance with the data in the table below. Let us explain that the table indicates the time required to heat the parts. However, the data applies to an air temperature of 20°C. If you work at a lower temperature, then you need to heat the parts longer, and if at a higher temperature, then reduce it. The following table shows the soldering time for polypropylene pipes.

6. After heating, remove the parts from the soldering iron and connect them together. Here we draw attention to the fact that the connection must be made without rotation along its axis and to the entire depth of the fitting socket. The operation must be performed quickly while maintaining alignment.

7. If you did everything correctly, then after connecting, a continuous influx of plastic should appear along the edge of the socket. You can see an example below.

8. Next, allow time for the parts to cool. During this period, various types of deformations (bends or rotations along the axis) are unacceptable. Here we draw attention to the fact that if a connection has occurred and the alignment or angle of relative position is shifted, then the part must be cut out and reinstalled. Soldering tees, angles and taps must be done with special attention. For example, the faucet handle should move easily.

If you do not know how to properly solder polypropylene pipes, then it is advisable to perform test soldering. To check the quality of the soldering, you can cut the prototype along its axis. The result should be a monolithic structure.

Do not forget that the technology for soldering polypropylene pipes requires compliance with safety precautions, because... You will carry it out using high temperatures, power tools and plastic, which will emit harmful fumes during heating.

The question often arises, what kind of material is polypropylene and how to solder polypropylene pipes. Today, to install plumbing, heating or sewerage systems, the popular method of soldering polypropylene pipes is used. This material is characterized by durability and high technical performance. Therefore, many are interested in how to properly solder polypropylene pipes to get an effective result. As with any installation, this process requires care and patience.

Soldering of polypropylene pipes is carried out using a soldering iron with special nozzles for heating the pipes.

Technical characteristics of pipes

Before you start work, you should know what type of pipes are needed for a certain process, and how to properly perform it with a special tool for this. Their assembly is carried out using a soldering iron and fittings, which include couplings, angles, tees, etc.

This type pipes is used when installing any type of pipeline. Moreover, they can be mounted both open and closed, for example, when grooved in a wall. To solder them, connecting fittings are used, which provide a cast connection, and threaded ones, in which it is detachable.

Polypropylene pipes are divided into 4 types. The first PN10 includes pipes whose operating pressure is 1 MPa. They have thin walls and are used when installing heated floors and for supplying cold water up to +20 °C. PN16 grade material is used for conducting cold water, as well as for heating systems with low pressure. Pipes of the PN20 type are universal and have a working pressure of 2 MPa. They are installed when laying any water supply, both for cold and hot water. The last type PN25 includes pipes with an operating pressure of 2.5 MPa. This material is reinforced with aluminum foil and is intended for installation of any heating system, as well as for hot water supply.

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Rules for soldering polypropylene pipes

Required:

• soldering apparatus;
• special keys.

Polypropylene pipes are connected to each other using a soldering iron with special nozzles. These include a sleeve, designed to melt the surface from the outside, and a mandrel, necessary to melt the surface of the bell directly at the connecting part from the inside. These nozzles are coated with Teflon and have diameters ranging from 16 to 40 mm. After each welding, the non-stick material must be cleaned hot with a tarpaulin rag or wooden scrapers.

Before work, the welding machine is installed on a horizontal surface for stability so that it does not fall. And replaceable nozzles of the size required for the job are fixed onto it using keys designed for this purpose. Their location depends on convenience during the installation process.

So, for example, to install a pipeline branch located on the wall, they are placed closer to the end. When performing work in a vertical position and in inconvenient places, another person is needed for soldering. To obtain a better joining of polypropylene pipes, all elements of the future pipeline are assembled separately.

Polypropylene pipes should be soldered while observing the temperature conditions. The heating of the soldering iron directly depends on the temperature environment and lasts for 10-15 minutes. In hot weather, the welding time should be reduced, and in cold air, on the contrary, increased. If the temperature is below 0 °C, connecting polypropylene pipes and fittings using a soldering iron is prohibited. The soldering process of this material is ensured only at 260°C. You also need to choose the right time interval for soldering and cooling, which depends on the diameter of the pipes, i.e. the larger it is, the more time is spent.

The device's readiness for operation is indicated by an indicator. To obtain a strong and reliable seam, the soldering iron must be fully heated. Otherwise, the parts will not reach the temperature of viscous plasticity, so diffusion of the material will not occur. If the soldering iron is overheated, excessive adhesion of polypropylene may occur and, as a result, loss of shape stability. During the entire soldering process, the device must be turned on at all times.

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Required:

• polypropylene pipes;
• welding machine;
• plastic cutter;
• shaver;
• welded seat.

Soldering of polypropylene pipes can be done using a coupling, socket or butt method. With a coupling connection, two parts are fastened together using a special coupling, and for threaded joints, fittings with a socket are used. This type of soldering is used for polypropylene pipes with a diameter of less than 63 mm. Butt welding is carried out without additional details and is performed for pipes with a diameter over 63 mm. The socket method of soldering pipes with a small diameter is carried out either with a manual welding machine or with centering devices.

To perform socket soldering, first use scissors or a plastic cutter to cut the pipe to the required length at a right angle. If the product is reinforced, then the ends must be cleaned. To do this, the top two layers are removed with a shaver: polypropylene and aluminum. Stripping is performed to a depth along the tool stop, which determines the welding depth. Next, the surface of the parts is cleaned and degreased. After this you can start soldering. First you need to heat the soldering iron to the required temperature and after 5 minutes you can start the first welding.

Soldering of connections must be done quickly, otherwise deformation may occur.

When heating, a rotation angle not exceeding 100° is allowed. To avoid unnecessary movements during the welding process, you must first mark the corresponding landmarks on the pipes. Once soldering is completed, allow the time required for cooling, especially for thin-walled material. In this case, during the cooling process, under no circumstances should the elements be rotated or bent. If the fittings were connected incorrectly, the connecting fitting must be cut to correct the error. When welding elements such as angles, tees and ball valves, their location is taken into account, in which the handle must move freely to any position. At the end of the work, all welded elements are fixed together and are not subjected to any loads. Use a tool with clean attachments.

If there is a need to install an additional outlet on an existing pipeline, then welded saddles are used. In this case, the work will require a special device with a drill and special attachments. welding tool for them. First, a hole is drilled in the pipe wall at a temperature of 260°C. A heating fitting is inserted into it so that the tool completely reaches the pipe wall from the outside. After this, the seat fitting is installed in the heating sleeve, and the surface of the welded seat should be completely close to the arch of the tool. All elements should heat up within 30 seconds. Then you need to remove the welding device and quickly insert the fitting into the heated hole.

The welded seat is pressed tightly against outer surface pipe and is fixed in a stationary position for about 15 seconds. It takes 10 minutes for the connections to cool, and after that you can subject them to any load.

The welded connection of polypropylene pipes is characterized by higher reliability compared to other methods of combining products with each other. This connection technology does not have any differences when working with polypropylene. The only exception is reinforced products: their installation requires some specific features.

This technique is quite simple. Welding can be carried out at home, observing the requirements of the technological process and having the entire arsenal of necessary tools.
There are several options for connecting polypropylene pipes:

• diffusion soldering;
• soldering with electrical fittings;
• cold welding.

In this article we will talk about each method of combining cylindrical products in more detail, consider their advantages and disadvantages, and also learn how to properly solder polypropylene pipes.

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

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

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

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

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

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

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

When the heating system of a private house is made of cylindrical products of this diameter, this kit will be quite sufficient. But if more professional work involving soldering is expected, you will need a better device.

For pipes with a cross-section of 40-63 mm, a different soldering kit is required. It will have to be purchased separately. The most expensive sets, characterized by increased reliability, are manufactured in large European countries. Their kit includes the following parts:

• soldering iron;
• stand;
• Teflon nozzles of different diameters;
• scissors that allow you to cut pipes at 90 degrees;
• hexagon;
• Phillips screwdriver;
• roulette;
• gloves.

Since you have to work with hot equipment to solder polypropylene pipes, you must wear gloves when performing the operation. Beginners often get burned when touching the heating element.

The design of any soldering iron is designed so that it is possible to install several nozzles at once for connecting small-diameter pipes, which saves time, especially when working with products with a cross-section of 20-40 mm.

Soldering machine power

To heat a pipe with a diameter of 63 mm evenly and quickly, you need high power systems. For domestic purposes, a device with a value that determines the amount of energy not exceeding 0.7-1 kW will be sufficient.

If the power of the iron is more than 1 kW, it becomes professional. Its cost is much higher than the price of an ordinary soldering iron.

Method one

To make a homemade soldering iron you will need:

• a broken old iron that still has a heating element;
• children's metal construction set;
• rubber handle;
• toggle switch;
• asbestos cord;
• duralumin;
• insulating tape.

Manufacturing technology

• use a grinder to cut off all unnecessary parts from the bottom of the iron;

• an aluminum cover is made;
• a box is assembled from the construction kit; a light bulb and a rubber handle are installed in it;
• a toggle switch and a soldering iron regulator are connected to the wire;

• all parts are combined into one whole;
• cables are soldered;
• The heating element is bolted to the body, having previously placed an asbestos gasket.

Thus, after spending a little time using available material, you become the owner of a homemade soldering iron for welding PP pipes.

Method two

To make the tool you will need a pair of attachments costing 215 rubles. and a discarded, set fire iron. It takes approximately two hours to assemble.

First, the heating device is installed vertically. The fitting is placed on the heating nozzles simultaneously with the pipe. To make it possible to carry out operations on the wall, the iron needs to be slightly modernized: cut off the “sting” of the sole and slightly round it. It would be a good idea to use thermal paste.

It is known that such homemade device several pipelines were welded. The quality of work turned out to be quite high.

After heating the iron, holding it by the handle, remove the pipe first. There is no need to remove the fitting immediately, since its thickness prevents it from melting quickly. All that remains is to hold the pipe with the iron with your hand and remove the fitting.

To connect the products, you need to apply little force until an even flash is formed around the entire perimeter of the fastener.

You need to hold the connection in this position for about 15-20 seconds until polymerization begins. Welding on the wall is simple: hold the heating device with one hand, and the pipe with the other.

Method three

We manufacture an iron equipped with a temperature controller, which will act as a special power control device assembled on a thyristor. For soldering work, a voltage of 170V is supplied. Aluminum or copper plates are used to create the device. The photograph shows a part with a thickness of 0.8 mm, but the value of this value may vary upward.

Flat elements are needed so that the heater does not begin to cool the moment the pipe is put on. For operation, a heating element (1 kW) from an outdated Mechta stove is used. Since the radiator hardly heats up, it can be reduced. No spacers are required to install the thyristor and diode. The design of the iron itself can have any shape, it all depends on your imagination.

Below is power regulator circuit.

On each side of the spiral you can install aluminum spacers in the form of round pancakes. A handle with a regulator and a fixed toggle switch is attached to the body. In other words, you can do tuning.

The principle of all devices is always the same: to solder PP pipes, you need to maintain a certain temperature.

How to choose nozzles

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

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

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

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

Normal temperature for soldering

For durable welding of structures, the soldering temperature of polypropylene pipes should not exceed 260 °C. Otherwise it will lead to loss of stability plastic base, as a result of which the pipe simply cannot connect to the fitting. Moreover, the heated connecting element will begin to stick to all the parts surrounding it. However, a lower temperature is also not suitable for soldering.

It is important to remember that the viscosity and ductility of the polypropylene structure must have certain values, otherwise diffusion processes will not begin, and the connection will lose its reliability. The service life of such pipelines will be minimal. You will have to forget about the 50-year warranty. It is better to look at the table at what temperature to connect the products.

Pipe soldering time

If you correctly follow the technology requirements for the duration of the process of connecting structures using a special tool, you can get a fairly airtight joint. Polypropylene will not begin to spread after overheating. Heating time depends on certain parameters. The main ones are:

• pipe section;
• welding belt seam width;
• ambient temperature.

Below is a special table that shows the recommended soldering time for PP products, taking into account all the values ​​​​mentioned above:

Socket welding of polypropylene pipes

The main method of installing plastic when you need to connect small cylindrical products different sections, the use of a bell is considered. When welding a PP structure, additional parts must be used:

• corners;
• tees;
• bends.

They are all made from the same material from which the pipes were made. Application additional elements to create a high-quality connection is not considered a disadvantage of this method. The parts in question, in addition to the connecting function, help change the direction of the pipeline.

This process consists of several operations:

• the mating surfaces are melted: the outer wall of the cylindrical product with the inner part of the fitting;
• special heating parts are used;
• The assembled elements are cooled.

According to professionals, socket joints are considered much more reliable than butt welding. Due to the fact that when combined, the pipe enters the fitting with force, high strength is created. In this case, alignment does not require the use of a special tool. Even a beginner can combine cylindrical structures in this way.

Socket welding machine

Devices designed for connecting PP products into sockets are called soldering irons or irons. The main element of such a device was the heating head. All replacement parts are attached to it:

• couplings;
• dorns.

The first elements are designed to heat the outer surface of the pipes, the second - the inner part of the fittings. The shape of the heater in most soldering irons remains a triangular plate. Devices of other designs can be found on sale.

The size of the nozzles depends on the dimensions of the flat part. In other words, a pipe section is selected that will be freely soldered. In addition, you need to take care of the right amount heating couples for simultaneous installation. To work with a large plate you will need a powerful unit.

Additional parts (couplings, mandrels) must be secured so that their supporting surface tightly touches the plate.

With good contact, the desired temperature (260 °C) will be achieved. In this case, the power of the soldering iron does not matter much.

Today, devices are produced equipped with a heating head in the form of a rod. Their main advantage can be called compactness. The head shape does not affect the technical parameters.

For high-quality operation of the iron, the accuracy of the functioning of the temperature sensor, which supports required temperature. If its fluctuations become minimal, this indicates a high quality soldering iron.

The most advanced today are electronic thermostats. These thermistors are capable of displaying an accurate temperature value even at work surface couplings.

The use of such parts makes it possible to reduce the temperature inertia of the iron. As a result, the true readings of the heating head will be displayed on the device scale.

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

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

These products are capable of independently achieving the desired temperature regime. The master himself selects the required power.

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

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

The equipment can be equipped with auxiliary tools, including:

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

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

Technological process of socket welding

The outer diameter of a cylindrical product is always slightly larger than the nominal cross-section. The fitting, on the contrary, has an internal diameter less than the nominal cross-section of the pipeline.

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

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

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

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

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

General technological process Connecting PP pipes into a socket has several sequential operations:

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

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

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

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

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

Composite pipes made of PP, which are reinforced with aluminum, are characterized by low thermal expansion. Therefore, a heating system made from such products does not require the installation of additional temperature compensators. Only in such products reinforced with aluminum is oxygen diffusion possible. After air enters the system, the water is actively saturated with oxygen. As a result, the process of cavitation of valves, as well as other parts of the structure from cylindrical structures, begins.

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

Technological map for socket welding of polyethylene pipes

How to solder reinforced polypropylene pipes

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

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

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

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

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

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

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

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

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

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

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

How to prepare a soldering iron for use

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

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

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

We put the parts to warm up

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

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

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

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

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

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

Cooling the connection

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

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

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

In this case, there is no need to use additional devices. If everything is done correctly, the result is a fairly reliable seam, not inferior to the strength of the pipe. The technological operation is performed in a certain sequence:

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

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

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

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

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

Installation work with a plastic pipeline involves cutting and connecting operations. By virtue of technical properties material, such problems are solved more easily 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. This 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 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 when in contact with metal surfaces, after which you can perform any connection actions 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.

We are also preparing additional accessories, which should be at hand during the operation. For example, the question of how to solder polypropylene in hard-to-reach places often involves 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 by mechanical means 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 exposure is the most responsible. 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 on 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 final stage with cooling. 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 devices manual type 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 They 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 are inserted. Soldering is needed just to prepare for such integration. To do this, use a soldering iron end plastic pipe warms up, puts the same fitting 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? Manual devices in this sense, they 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 intervention in the structure of the material itself does not entail a reduction in its performance 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.

Polypropylene pipes- pipes assembled by diffusion welding using fittings: couplings, angles, tees, etc. The estimated service life of polypropylene pipes is more than 50 years.

It should also be noted that the service life of polypropylene pipes declared by the manufacturer is 50 years, which implies that the pipeline will be operated at normal pressure and normal temperature. That is, pipes can withstand long-term significant pressures, but the temperature of the transported liquid must be low, or, conversely, the temperature of the liquid can be very high, but the pressure must be low. At high blood pressure and high temperatures, the service life of the pipe is sharply reduced and can reach up to 1-5 years. To determine the service life of pipes operating in extreme conditions, there is a special table. We will not present it in this book, since at the domestic level such long-term loads do not occur in home pipelines, and the pipe will withstand short-term emergency situations associated with a sharp rise in pressure or a sharp jump in the temperature of the transported liquid.

Polypropylene pipes come in gray, white, black and green. Color other than black does not mean any restrictions on the use of pipes. The black color of the pipe indicates that it is most protected from ultraviolet radiation.

IN polypropylene water pipes Permanent connections are used, pipes are assembled on welded fittings once and for all.

Polypropylene pipes can be used for:

Water supply to houses: installation of risers, installation of pipes, connection of pipes to water supply networks from metal pipes

Heating a house: installing heating risers. Installation of heating pipes, connections to the boiler installation, connection to metal radiators.

The long service life of polypropylene pipes allows them to be used for laying all types of pipelines:

open gasket;

wall gaskets;

in a closed gasket;

Polypropylene pipes are divided into 4 categories

- PN 10- thin-walled version, for cold water supply (up to +20°C), nominal operating pressure 1 MPa (10.2 kg/cm/2);

- PN 16- cold water distribution high blood pressure and reduced pressure central heating pipelines;

- PN 20- universal pipe used for cold and hot water supply (temperature up to +80°C), nominal pressure 2 MPa (20.4 kg/cm2);

- PN 25- reinforced with aluminum foil, for hot water supply and central heating (up to +95°C), nominal pressure 2.5 MPa (25.49 kg/cm-).

Unlike metal-plastic pipes the aluminum layer in these pipes is closer to outside and, most often, there is perforation on it, which makes it possible not to use glue to fasten the layers of the pipe. The connection of the outer and inner layers of polypropylene to each other or to the aluminum layer occurs through perforated holes, which, in turn, can be through-hole or superficial from different manufacturers. The direct connection of polypropylene with aluminum significantly increases the stability and strength of the pipes.

Thanks to this connection, PN 25 pipes have thinner walls than conventional polypropylene coarse pipes and allow higher consumption liquids.

Intended for special use- mainly in heating pipelines, as well as in hot water supply pipelines, but can also be used for cold water supply systems.

They also allow you to connect polypropylene pipeline to metal. The pipes are environmentally friendly and are successfully used in cold and hot water supply and heating pipelines. Thanks to fittings with chrome and brass inserts, pipes can be easily combined with existing steel reinforcement and plumbing fixtures.

Fittings used for connecting polypropylene pipes

Connection fittings

Used to connect 2 or more polypropylene pipes.
Main sizes: 20 x 1/2, 20 x 3/4, 25 x 1, 32 x 1, etc.

Fig.1. Coupling for connecting polypropylene pipes of the same diameter;

Fig.2. Coupling for connecting polypropylene pipes of 2 diameters;

Fig.3. Angle 45°;

Fig.4. Square 90°

Fig.5. 45° elbow for connecting pipes of different diameters;

Fig.6. 90° elbow for connecting pipes of different diameters;

Fig.7. Triple square;

Fig.8. Tee with identical fittings (connection of pipes of the same diameter);

Fig.9. Transition tee (connection of pipes of the same diameter);

Fig. 10. Crosspiece;

Fig. 11. Plug for polypropylene pipes;

Fig. 12. Thermal expansion compensator;

Threaded fittings for polypropylene pipes

Rice. 1. Transition (coupling) with internal thread;

Fig.2. Transition (coupling) with external thread;

Fig.3. Transition (coupling) with transfer nut;

Fig.4. Transition (coupling) with a transfer nut and a metal insert;

Fig.5. Transition with external plastic thread type “DG”

Fig.6. 90° elbow with internal thread;

Fig.7. 90° elbow with external thread;

Fig.8. 90° elbow with changeover nut;

Rice. 9. Tee with internal thread;

Fig. 10. Tee with external thread;

Fig. 11. Tee with switch nut;

Fig. 12. Water socket angle for fastening the mixer and other appliances: 20 x 1/2, 25 x1/2;

Fig. 13. Set of water sockets for mixer: 20 x 1/2, 25 x1/2;

Fig. 14. Fitting with transfer nut;

Fig. 15. Welded seat with internal thread;

Fig. 16. Welded seat with external thread;

Fig. 17. Collapsible connection;

Fig. 18. Dismountable connection with internal thread;

Fig. 19. Dismountable connection with external thread;

Welding (soldering) of polypropylene pipes

For welding pipes with a diameter of up to 63 mm, the preferred type of connection is socket or socket welding. In this case, the connection of two pipes occurs using a third part - a coupling, and the creation of threaded and other connecting units occurs using fittings with a socket.

For welding pipes with a diameter above 63 mm, butt welding is recommended as it does not require additional parts and is the most reliable. If there are fittings of the appropriate diameter, sleeve welding is allowed. Recommended view collapsible connection for diameters greater than 63 - flange joint. This is a more complex option for connecting polypropylene pipes, requiring professional equipment and skill, so this option is omitted from this article.

Socket welding

When welding pipes with diameters up to 40 mm, you can use a manual welding machine; when welding pipes with diameters over 40 mm, it is recommended to use machines with centering devices. When using centering devices, follow the instructions for their use.

To connect polypropylene pipeline parts, welding machines with special nozzles are used.

Fig.1. Welding machine for welding polypropylene pipes.

The heating elements (nozzles) are a sleeve for melting the outer surface of the pipe end and a mandrel for melting the inner surface of the socket of the connecting part.
Standard nozzles are coated with non-stick material - Teflon, and have diameters from 16 to 40 mm. During operation, it is necessary to monitor the cleanliness and integrity of the Teflon coating. After each welding episode, while they are still hot, the nozzles are cleaned with a canvas rag or wooden scrapers. In a cold state, cleaning the nozzles from the adhering layer of plastic is unacceptable.

Fig.2. Nozzles for welding polypropylene pipes with a diameter of 20, 40, 32, 40, 50, 63.

The welding machine is installed on a flat surface and replaceable heaters of the required size are secured to it using special keys. It is advisable to install all necessary set nozzles (see Fig. 3) on seats device until the device heats up.

Fig.3. Welding machine before heating with installed nozzles for welding polypropylene pipes.

From the point of view of heating uniformity, the location of the nozzle on the heater does not matter. Therefore, the nozzles are placed in a way that is convenient for installation. Closer to the end, place the nozzles necessary for working on the wall, that is, on the pipeline branch being mounted.

The quality of connections directly depends on the convenience of performing technological methods, therefore, it is better to assemble all pipeline fragments that can be mounted on a permanently installed device (on a stand) separately.

It is advisable to carry out welding “on the wall”, especially in inconvenient places, with an assistant.

The welding temperature for polypropylene pipes is set on the machine - 260 ° C and 220 ° C for polyethylene and PERT pipelines).

Depending on the ambient temperature, heating lasts 10-15 minutes.

The operating temperature on the surface of the heating plates is achieved automatically.

Welding of polypropylene pipes and fittings is prohibited at temperatures below 0°C. The air temperature during welding is very important. So the welding time must be increased at low air temperatures and reduced in hot conditions.

General rule for socket welding

The inner diameter of the unheated fitting should be slightly smaller than the outer diameter of the pipe.

Socket welding of plastic parts to each other is carried out as follows.

1. Use scissors or a pipe cutter to cut the pipe at a right angle.

2. If necessary, clean the end of the pipe and the socket of the fitting from dust and dirt, degrease with alcohol or soapy water and then dry.

When welding PN 10 and PN 20 pipes, nothing else needs to be done at this stage.

When welding reinforced pipes PN 25 special tool Using a shaver, remove the top two layers of polypropylene and aluminum from the pipe. The size of the fitting socket is made in such a way that a pipe can only fit into it with removed top layers. The depth of stripping is carried out according to the stop of the tool, which determines the depth of welding.

Fig.5. Shaver

Fig.6. Processing the pipe with a shaver.

3. Apply a mark to the pipe at a distance equal to the depth of the socket plus 2 mm. If you use rough parts, fittings and tools from the same manufacturer, then, most often, you don’t need to do any calculations. The shaver (Fig. 2) removes the top layers of the pipe exactly to the welding depth, and the dimensions of the heating nozzles are such that it is impossible to insert a pipe into them to a depth greater than required.

4. Place the parts to be joined on the appropriate nozzles: insert the pipe into the sleeve to the mark indicating the welding depth, and put the fitting socket on the mandrel.

5. Maintain the heating time (see Table 1), then remove the parts from the device and connect them to each other without turning the parts along the axis. Welding fittings must be connected to the pipe with a quick, confident movement, maintaining the alignment of the pipe and coupling. The connection between the pipe and the fitting must occur to the depth determined by the boundary inside the fitting socket.

6. After welding, it is necessary to maintain a cooling time, especially for thin-walled pipes. Rotation and bending (deformation) during cooling are not permitted. Connection with poor alignment or angle relative position fittings are subject to only one method of correction - the incorrectly connected fitting is cut out. You must be especially careful when welding elements for which position is important - angles, tees, ball valves. The latter must be welded so that the handle can move freely to all positions.

If you are soldering (welding) polypropylene pipes for the first time, you can cut the first connection to check, it should look like this:

Table 1. Technical specifications welding (soldering) of polypropylene pipes.

The welding machine must be constantly switched on during the entire welding process. Heating begins simultaneously for two parts.

If underheating occurs, there is a possibility that the parts will not reach the temperature of viscous plasticity. In this case, the connection will be unreliable and diffusion of the material may not occur.

When overheated, there is a possibility of loss of shape stability, the adhesion (stickiness) of the material will be excessive. It will be impossible to insert the pipe into the fitting, and as the force increases, the edges of the pipe will bend inward or become wrinkled. The connection will be narrowed.

The outer surface of the connecting part welded to the pipe should not have cracks, folds or other defects caused by overheating;

At the edge of the socket of the connecting part welded to the pipe, a continuous bead of melted material should be visible around the entire circumference, protruding beyond the end surface of the connecting part.

Instructions for welding welded seats

Welded saddles are used for installation of subsequent branches from the pipeline during the repair of existing systems.

First you need to drill the wall of the plastic pipe with a Fusiotherm drill.

When using combined Stabi pipes, remove any remaining drilled hole aluminum using the Fusiotherm chamfering tool.

Fig.1. Drilling a hole in the pipe wall.

The welding device/saddle welding tool must reach the required operating temperature of 260°C.
The surfaces to be welded must be clean and dry.

Fig.2. Installation of a welding machine;

The heating connection of the saddle welding tool is inserted into the hole in the wall of the plastic pipe until the tool reaches the entire outer wall of the pipe. The welded seat fitting is then inserted into the heating sleeve until the surface of the seat reaches the crown of the tool. The heating time of the elements is 30 seconds.

Fig.3. Heating of the pipe and seat.

After removing the welding tool, the welded seat fitting is quickly inserted into the heated hole. Then the seat should be pressed accurately and tightly, without rotating, onto the heated outer surface of the plastic pipe.

Fig.4. Installation of a welded seat;

The welded seat is fixed motionless on the pipe for 15 seconds. After 10 minutes of cooling, the connection can be subjected to full load. The corresponding branch pipe is welded into the coupling in the usual way.

Fig.5. Finished welded seat.

Examples of finished polypropylene pipelines welded by socket welding

The simplest example of polypropylene pipes in a bathroom:

The simplest example of polypropylene pipes from a toilet to a bathroom) Please note that the polypropylene pipeline is removable).

Piping made of polypropylene (a more complex option), all pipes are wrapped in thermal insulation to prevent the formation of condensation for cold water and reduce heat loss for hot water).

In conclusion, I would also like to indicate the thermal expansion coefficients of metal-plastic pipes and polypropylene pipes:

For metal-plastic pipes (PEX-AL-PEX) = 2.6 *10 -5

For metal-plastic pipes with a reinforcing layer of ethylene vinyl alcohol (PEX-EVOH-PEX) = 2.1 * 10 -5

For polypropylene pipes, without reinforcement (PP) = 15 * 10 -5

For polypropylene pipes with an aluminum reinforcing layer = (PP ALL-PP) = 3*10 -5

Well, a little clarity in these numbers:

When the ambient air temperature, or the temperature of the liquid inside the pipe, changes by 10 degrees Celsius, each meter of pipe will lengthen or shorten, respectively:

PEX-AL-PEX = by 0.26 mm

PEX-EVON-PEX = 0.21 mm

PP-ALL-PP = n 0.3 mm

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