DIY repair of polypropylene heating pipes

Polypropylene pipes are characterized by enviable chemical resistance and a fairly high ring stiffness. However, the physical resistance of such products to shock or mechanical stress leaves much to be desired. Therefore, the repair of polypropylene pipes is a fairly common operation. We will try to mention all sorts of causes of accidents in such pipelines and methods of eliminating the consequences of accidents in gravity and pressure polypropylene systems.

The pressure in free-flow systems is equal to atmospheric pressure. The capacity of such lines is calculated in advance. In addition, the installation of joints in free-flow systems is carried out according to the socket technology, with the sealing of the contact point with an ordinary rubber seal. That is, in this case, there is no need to fear excessive internal pressure or errors in the assembly of the pipeline.

As a result, only a "third force", malicious or accidental, can damage the polypropylene pipe in such a system.

Simply put: the cause of an accident in a free-flow system can only be a third-party effect, as a result of which the pipe body was damaged.

Moreover, such an impact may also look like an attempt to discharge a chemical substance with a high

activity, and how the operation of the system with a deliberate violation of the temperature regime, and as a trivial mechanical damage.

However, theoretically, another reason for such accidents could be factory defects that were not noticed in the technical control departments of a polypropylene pipe manufacturing plant. However, such defects in polypropylene pipelines are not common. The production process of such products is controlled quite carefully.... Therefore, this "reason" can be neglected.

Construction standards, which regulate the laying of polypropylene pipelines, allow the use of such structures not only in gravity lines, but also in pressure systems.

Therefore, in addition to the mentioned outside forces, the list of causes of accidents should also include the risks associated with exceeding the permissible pressure in the pipeline, and the dangers provoked by errors in the installation of the pressure line.

After all, the pressure pipeline is mounted on a sufficiently strong welded joint that does not forgive technological errors. Misalignment of the pipe in the coupling, errors in the soldering process, breakdowns of the welding machine - this is just a short list of the causes of accidents at the joints. Moreover, most of the accidents of pressure pipelines are provoked precisely by "docking" reasons. Therefore, we will begin the analysis of methods for eliminating leaks and breaks in pipes by studying ways to deal with poor-quality joints.

Repair of polypropylene pipes, as well as products from any other polymer, begins with the localization of meta leaks. Moreover, at the very beginning, the plumbers examine the joints of the system. After all, three quarters of the problems of gravity and pressure pipelines are associated precisely with the joints.

Polypropylene pipelines in non-pressure systems can leak at the joints for only one reason - due to the skewing of the O-rings in the socket... Therefore, when installing free-flow systems, it is necessary to control the location of the rings using a special probe, which can be made from a beer can. This "tool" is inserted into the joint gap and measures the depth of the "occurrence" of the sealing ring. And if in the process of measuring the depth you observe different depths, then the ring is uneven.

Repairing a polypropylene pipeline, in this case, involves only dismantling the joint with the replacement of the ring. That is, you will have to remove the pipe from the socket and replace or fix the O-ring. After that, the pipe is inserted into the socket, and the problem is considered solved.

The joint in the pressure pipelines is assembled for welding. And mistakes in the assembly process mean only one thing: you have to cut out the damaged joint from the pipeline and replace it with a new element.

Cutting of polypropylene pipes, in this case, is carried out as close as possible to the damaged joint. After all, polymer pipelines are sensitive to linear temperature deformations, therefore, we can cut out a three or four centimeter section and simply connect the free ends without extending (cutting) the length of the pipe.

After the section with the problematic coupling has been cut out of the pipeline, you will have to find a new fitting and re-solder the problematic assembly. Only in this case, try to avoid typical mistakes in the process of soldering polypropylene pipes.

In short, take the following precautions:

• control the depth of immersion of the pipe in the coupling,
• enter the correct values ​​for the pipe diameter and wall thickness into the control unit of the welding machine
• press the pipes into the coupling in one motion, without turning.

And if you are not mistaken in these "little things", then you will not have problems with the new joint.

In both gravity and pressure systems, the pipe body is repaired using the same operation: installation of a temporary or permanent "patch". Moreover, a rubber band, a collapsible coupling, and a segment of the same pipe can play the role of a patch. The tourniquet is wound around the pipe body, over the hole. The ends of the bundle are fixed with a screw clamp or ordinary wire. In addition, the repair of polypropylene pipes, in this case, can be organized with the help of ordinary textiles, impregnated, at each turn, with epoxy resins.

The collapsible sleeve crimps the deformation point and is fixed on the screws. Moreover, at the very beginning, the lower part of the coupling is brought under the pipes, pressing the breakthrough with the upper side of the product.

With this order of assembly of the coupling, you can neglect the need to turn off the pressure in the pipeline..

A segmental patch is only mounted on an “empty” pipeline. It is cut from the body of a similar pipe and fixed with glue. Moreover, on top of the glued area, it is best to also apply a threaded clamp that tightens the patch both during the drying of the glue and during the operation of the pipe.

If the reason for the repair was a very serious accident that destroyed a significant section of the pipe body, then you should not exchange for patches or couplings - just replace the entire damaged section with a new, workable analogue.

The destroyed section of the free-flow pipeline is simply removed from the lower one and disconnected from the upper (along the flow) sockets. The new pipe is first inserted into the lower socket and then attached to the upper, smooth end. In this case, one should not forget about the need to control the location of the O-rings.

Replacement of damaged sections of polypropylene pipes in pressure systems is based on the complete removal of the damaged segment and two welded sleeves. Therefore, the assembly of a new segment begins with the installation (soldering) of new couplings. And after that, all you have to do is weld a measured piece of pipe of the required diameter into the free ends of the couplings.

In the process of arranging welded joints, it is worth paying attention to the depth and quality of the soldering. Otherwise, you will also have to deal with low-quality joints.

Polypropylene pipes are an easy-to-use and inexpensive material. How to lay a pipeline in an apartment or house using a polypropylene pipe?

Reliable installation of polypropylene pipes

To install polypropylene pipes with your own hands, you will need the following tool:

1. an electric welding machine with teflon nozzles of different sizes to connect the pipes to each other;
2. pipe cutter - a device in the form of scissors, the incisors of which are wedge-shaped;
3. a reamer calibrator to prepare the pipe ends and chamfer the inside.

After purchasing the necessary tool, they develop a wiring diagram for water supply and heating, in which all pipes will be hidden in a gate or be in direct accessibility (open method).

There are two schemes for water intake:

1. parallel (from the collector);
2. sequential (the points of water intake and drainage are connected through a tee to the mains).

A sequential scheme is considered more economical, but if there are many intake points in the room, and the water pressure is weak, it cannot be used. The parallel circuit is suitable for large rooms with low water pressure and a large number of connected equipment. Water intake in a parallel circuit is made from a manifold collector. A comb is a prefabricated structure of several valves, from each of which there is a branch to a new parsing point.

1. all the plumbing to which the pipeline will fit (if the toilet is not in the bathroom, the piping to it is also taken into account);
2. pipes with hot and cold water, their size and marking;
3. accounting equipment (meters);
4. drain and emergency valves;
5. shut-off valves;
6. all points of intake and discharge with the indication of the consumer;
7. direction of water flow.

Only after that they start the practical part of the work - the purchase of pipes in the required quantity and additional elements.

To choose a suitable pipe model, you need to take into account the conditions in which the future water supply will be used. Pipes intended for use inside a building cannot be used outside - the products will not withstand the harsh conditions of use. In addition to the purpose, attention is paid to the marking that is present on each segment - it indicates the scope and purpose of a particular product.

1. pipes marked PN 10 are used only for supplying or removing cold water;
2. products marked with the designation PN 16 are allowed to be installed in any conditions of domestic water supply;
3. products designated as PN 20 are used both for supplying hot or cold water and for heating a house;
4. products marked with a PN 25 value are used only for wiring the heating system of an apartment or house.

Products marked with PN 20 and 25 have additional fiberglass or foil reinforcement, which will protect pipes from deformation due to high temperatures.

It is necessary to buy in the appropriate quantity and fittings according to the number of pipe connections (straight, angle, tees, and so on).

To install a plastic pipeline you will need:

1. couplings;
2. corners;
3. crosses or tees;
4. adapters;
5. nipple bends;
6. connector fittings;
7. stubs;
8. Ball Valves;
9. clamps or tiles for installation.

A single-pipe scheme is considered simple, since in it all radiators are installed one after another, and each subsequent one will be cooler than the previous one. This arrangement reduces material consumption, but heat will not be evenly distributed when using it. There is no reverse flow in a one-pipe system, and it can be either horizontal flow-through or top-wired (vertical). The standard layout (horizontal) can be additionally equipped with thermostat valves, adjustment for each radiator, ball shut-off valve.

Another plus of this scheme is the ability to make wiring above or below the floor. It does not take up space, and saves on additional finishing costs, hides the joints. It's easy to mount such a system.The main thing to remember is that the polypropylene pipe running under the floor must be insulated to reduce heat loss and the effect of temperature on the floor covering. The supply line is slightly sloped, which is why the natural force of gravity makes the water circulate better.

A two-pipe wiring diagram is considered a suitable way to heat a private house. In this case, the pipes are laid in the floor or walls along the entire perimeter of the structure, and the "return" is fed to the boiler. Otherwise, this scheme is identical to the one-pipe.

The calculation of heating begins with the selection of a heating boiler, the selection of the optimal characteristics based on the calculation of the specific heat loss. Calculated by the formula:

where Q is annual - the estimated heat consumption for heating the house during the cold period;

Fh is the area of ​​the building that will be heated.

Next, the heat consumption in a private house is calculated:

where Βh is the value that takes into account the heat consumed by the heating system itself (use the standard value for private houses 1.11);

Qvn life - heat supply from other sources;

ν is an indicator that takes into account the accumulation and release of heat by the walls of the building (take the standard value for private houses 0.8);

Qktot - total heat loss in the house.

The total heat loss for a building is calculated as follows:

where χ1 is the size factor (taken 0.024);

∑F - total internal area of ​​the room (walls, floor and ceiling, measured in square meters);

Dd - degree days in the heating season, which are determined based on the temperature zone of the location of the house (the value for the first zone is 3750, for the second - 3250, the third - 2750, the fourth - 2250).

1. First of all, they choose the place of installation of the boiler. Gas-powered equipment cannot be installed in the basement - for this, a concrete or metal "stage" is made, on which the heating element will stand.
2. Cut the pipes to length according to the diagram.
3. Remove burrs after cutting the pipe.
4. Mark with a marker the measured length to which the pipe will enter the coupling. To do this, the end of the pipe is not fully inserted into the fitting.
5. The pipe and the fitting are pushed onto the Teflon nozzle of the welding machine (first the part, the walls of which are thicker, and then the thin part), and warm up for the required time. Determine the exact warm-up time according to the table in the instructions.
6. After warming up, the elements are removed from the apparatus and connected according to marks, avoiding rotational movements, distortions. The elements are connected to each other according to the scheme.
7. Connect the flue pipe to the flue duct using heat-resistant sealants or a clay solution.
8. After that, connect the main pipe (main), the diameter of which will be larger than the diameter of any other pipe in this system. If the line is steel, its diameter should be at least 2.2 cm, and for metal-plastic - at least 2.6 cm. When installing 3 or more radiators, polypropylene pipes are not used.

An exclusively metal pipe is connected to the boiler without the use of any adapters. The expansion tank is mounted at a height of 3 meters from the boiler (at least!) - it is the highest point of the entire system. After that, pipes are laid and radiators, air discharge valves for each heating section are installed. Mount batteries under windows and lay pipes without bends. Mount the water supply and drain system, lock the structure on the boiler.