How to solder polypropylene pipes

Polypropylene pipes have a lot of advantages over other types of materials. They are not exposed to corrosion and fungus formation, have a high wear resistance and a wide temperature range conduct liquids. Therefore, plastic products are widely used in domestic and industrial construction and repair work.

Polypropylene pipes are installed using a specialized soldering device. The connection of a plastic pipe with elements of a water pipe from metal is carried out by special connecting details. How to solder pipes made of plastic is described below.

Heat resistance of polypropylene pipes

For a better understanding of the rules for working with any kind of materials, it is necessary to know the general characteristics and properties of the material itself. The first characteristic of plastic pipes, which is worth paying attention to - heat resistance. Products made of plastic lose their solid properties at a temperature of 1400C, this figure depends on the type of pipe. Producers point to their products the maximum temperature regime for which it is intended. On average, this figure is 950C for non-reinforced pipes.

For heating systems and water supply with hot water, special attention should be paid to the type of pipes to be purchased. High temperature resistance is demonstrated by reinforced pipes that combine the qualities of plastic and metal structures. Another indicator, which draws attention to the selection of material - the maximum allowable pressure in the pipe. All these figures are indicated by the manufacturer directly on the pipe itself.

Thermal elongation of polypropylene pipes

Thermal elongation is an indicator of the change in linear dimensions when heated. The straight and long section of the tube is covered by waves when heated and sags. Installation of heating systems or hot water systems should not be carried out from overlapping to overlapping by one section of the pipe. Otherwise there will be tension in the riser, this will lead to deformation of the pipe and a lot of trouble. How to solder the heating pipes to avoid problems:

• Use pipes with reinforcing coating to feed water, as already mentioned above. The coefficient of thermal elongation for this type of product is 5 times lower than for non-reinforced ones, besides, the higher the allowable pressure.
• Use expansion joints - bends of pipe section in the form of the letter "P".In this case, the elastic plastic will remain straight when elongating, as the legs near the bend will converge. For the installation of a heating system, experts recommend using both methods described.

Reinforced polypropylene pipes

Reinforced pipes are products with a rigid frame made of aluminum or fiberglass. Reinforcing aluminum layer is located outside or between layers of plastic. The layers are joined with special glue. The thickness of the aluminum layer is 0.1-0.5 mm. Fiberglass reinforcement is performed a little on a different principle - the layer is located only in the center, and the tube itself is a monolith, the layers in which are reliably welded to each other.

The presence of a reinforcing layer affects not only the characteristics of the pipe, but also the method of its adhesion. In general, the process of installing a reinforced pipe is no different from laying non-reinforced structures. There is only one nuance - a pipe with an external reinforcing layer of aluminum before soldering is cleaned with a special tool - shaver. Reinforced inside the product is peeled.

Reinforced pipes are more expensive than uncoated products, therefore it is not advisable to perform cold water installation. With a cold water line, ordinary polypropylene pipes will do fine.

Types of pipes and fittings

Polypropylene pipes are divided into 4 main categories:

1. The product with thin walls PN10 for underfloor heating and cold water supply systems. The pressure indicator is 1 MPa, the maximum temperature is 450C and 200C.
2. Product PN16 for installation of heating systems with low pressure and cold water supply systems. The pressure indicator is 2 MPa, the upper temperature index is 800C, the inner reinforcement is aluminum.
3. Product PN20 universal for cold and hot water supply. The pressure indicator is 2 MPa, the upper temperature threshold is 800C.
4. Product for laying cold and hot water supply PN25, internal reinforcement with aluminum. The pressure indicator is 2.5 MPa. The upper temperature index is 950C.

For the connection of pipes made of polypropylene and steel products, fittings with chromed and brass inserts are used. The main types of fittings:

1. Soldered couplings for products of the same and different diameters.
2. Angles 45 and 90 ° for products of the same and different diameters.
3. Corner triple and tee for products of the same diameter.
4. Blanket.
5. Soldering from polypropylene.
6. Cross.
7. Couplings combined with different types of thread - internal, external and with nakidnymi nuts.
8. Welded saddle.
9. Corners 90 combined.
10. Tees combined, external and internal thread, combined nuts.
11. Combination angles for fixing various devices.
12. Ball valves are ball, with an American, straight and angled.

Required tools

Special soldering equipment is used for soldering plastic pipes. Such a machine is sold in any construction shop, the cost is from 100 EUR.The simplest mechanisms have a heating element power of about 800 W, which is quite enough for building communications in an apartment or a private house. Professional soldering irons have temperature adjusters with an accuracy of 1-5 ° C. The soldering power does not affect the power, it determines only the heating rate of the element to the required temperature.

The standard soldering iron for polypropylene pipes has a nozzle with a diameter of 20, 25 and 32 mm. These dimensions are suitable for standard pipes, couplings and couplings. The nozzles are part of the heating element, have a sleeve that fuses the outer part of the tube, and a mandrel for the internal surfaces of the materials to be bonded. Well, if the nozzles have Teflon coating, it protects them from the impact of molten plastic, facilitates the removal of the molten pipe, increases the quality of welding.

Soldering iron is the main tool that is necessary for laying polypropylene pipes, but apart from it you will also need:

1. Roulette - for measuring the required pipe dimensions.
2. Pencil - for marking pipes and walls.
3. Hacksaw for metal - provided there is no special knife for plastic pipes.
4. Sharp knife - for chamfering from the pipe during installation.
5. Construction level.
6. Shaker for pipes reinforced from the outside.
7. Trimmer for reinforced pipes inside.

Special attention should be given to cutting pipes before installation. The optimum tool for this is the special scissors made of high quality steel. With their help, the pipes are cut straight, at an angle of 90 degrees. This saves time during installation and makes the process simpler. Often manufacturers introduce such scissors as a bundle of a soldering iron for pipes, therefore, when buying a soldering iron, it is worth taking a closer look at the contents of the box.

Operating instructions for soldering iron

1. The soldering iron is installed on a flat surface. The special keys fix the nozzles of the required diameters. The nozzle, which will be needed for soldering on the wall, is installed from the edge.
2. Separate pipeline parts are assembled on a stationary soldering iron. When assembling chains, it is convenient to work on the wall with an assistant.
3. Work starts only after the soldering iron is fully heated. For heating to 260 degrees it takes about 10-15 minutes. More precisely, this figure is indicated in the instructions to the device.
4. Soldering iron is not disconnected from the mains during the entire installation process.
5. Two connected parts are heated simultaneously.
6. Remains of plastic from the nozzles are removed immediately after the end of the adhesion with a canvas rag. It is not permissible to clean the cooled nozzles.

Instruction for soldering polypropylene pipes

1. The soldering device is switched on for warming up. Standard mechanisms have two indicators - a thermostat and the device's switching on. The indicators do not go out during the heating of the soldering iron, after 10-15 minutes, the thermoregulator indicator goes out. This indicates that the soldering iron has warmed up and is ready to work.
2. The soldering iron consumes more energy during the first start-up, the nozzle often proves to be heated above the required temperature. Therefore, it is advisable to wait for the switching on and off again of the thermostat indicator, and then start to work.
3. A piece of pipe of the required length is measured. The length is taken with a margin, the depth of the nozzle and fitting is taken into account.
4. Measured piece of pipe is cut with special scissors or metal hacksaw.
5. A suitable fitting is selected - its internal diameter must be wider than the outer diameter of the pipe when not heated.
6. It is wiped from the dust by the socket of the fitting and the outer part of the pipe, it is degreased with a soap solution or alcohol and dried.
7. Parts are installed on the tips of the soldering iron. The pipe is inserted inside the nozzle liner, and the fitting is put on the mandrel.

The parts on the soldering iron are kept for the time necessary for their diameter and width. This value is determined using the table:

Pipe diameter, mm	Belt width, mm	Heating time, sec	Connection time, sec	Time to cool the solder, min
20	14-16	6	4	2
25	15-18	7	4	2
32	16-21	8	6	4
40	18-22	12	6	4
50	20-25	18	6	4
63	24-28	24	8	6

The heating time in the table is indicated taking into account the room temperature - about 200C.At lower or higher rates, the time, respectively, increases or decreases. Do not solder at 00C.

1. The parts are removed from the soldering iron and connected to each other without turning on the axis. This is done with a little pressure. The pipe is inserted into the fitting to its full depth. The connection becomes reliable after the plastic has completely solidified. This value is indicated in the table above.
2. If the edges of the socket have a continuous ridge in the form of a roller along the entire circumference, then the connection is made correctly.
3. Do not rotate the pipe or bend it during the cooling period. If the connection has an angle or offset, it must be trimmed and re-made. Tells in detail how to solder the pipes, video at the end of the article.

The process of soldering reinforced pipes differs somewhat:

1. The chamfer is removed from the outside of the pipe, the reinforcement is sheared off.
2. If the pipe is reinforced with aluminum from above, then it is simply put into a sweep and made a couple of turns.
3. If the reinforcement is internal, then the reinforcement layer is pressed down with a force to the scraper-end and rotated.
4. Next, the process repeats the spike of non-reinforced pipes, which has already been described above.

Some useful tips for

1. To learn how to solder pipes made of polypropylene, you need to understand that in this process the most important thing is to act quickly and confidently and respect the ratio of parts. If the pipe is soldered for the first time, it is advisable to perform several test connections. To check the quality of the performed adhesion, the control sample is cut along.
2. During the work, special attention is paid to corners, tees and cranes. Handles of cranes should move freely in any position and not rest against a pipe. It is also necessary to carry out safety engineering, since the work is carried out at high temperatures, using plastic material, which, when heated, releases hazardous vapors.
3. Chamfering from the pipe is mandatory, and it must also be removed from the inside of the fitting. Otherwise, softened plastic during soldering will be seized, the connection will become less durable.
4. Insert the pipe into the fitting as far as it will go. The pipe is welded to the pipe along the entire length and its end. This point is especially important for products with an internal reinforcing layer.
5. Teflon-coated soldering tips can not be cleaned of plastic debris with metal objects. Remove residual polypropylene with a coarse cloth with a heated nozzle.