» PE-RT pipes - characteristics of new pipes for plumbing
The popularity of PEX series plumbing pipes made of cross-linked polyethylene has suddenly been called into question. And it was done by none other than the manufacturer himself. The American company Legend recognized the undeniable popularity of PEX and at the same time noted the negative properties of this product. The PEX pipe series suffered from a serious operational drawback - residual traces of chemicals in the water. Plus, disposal and recycling promises a lot of difficulties. Therefore, new PE-RT plumbing pipes, based on bimodal polyethylene, are confidently displacing the PEX series from the leading position in the plumbing market.
PE-RT series for plumbing
The American company Legend began producing innovative plumbing products that are functionally and technically more advanced back in 2015.
Polyethylene plumbing hoses for heating and hot water supply, marked with the “HyperPure PE-RT” brand, increase the efficiency and performance of the hydraulic system.
Do you dream of comfort? Do you want a warm floor in winter, and in summer - cold ceiling and walls? All this can be achieved with modern polyethylene pipes: cross-linked PEX and heat-resistant PERT. They can be installed without the help of specialists with your own hands. Read the article about how to select and install polyethylene pipes.
There are 5 main types of pipes:
Steel or galvanized (ferrous metal - an alloy of iron with carbon and other elements)
Copper (non-ferrous metal)
Metal-plastic
Polypropylene
Polyethylene (made of cross-linked polyethylene)
Each of the above types has its own purpose, is suitable for certain methods of laying pipelines and the properties of the transported medium (maximum and minimum temperature and pressure).
Today, heavy, unaesthetic metal pipes are being replaced by lightweight metal-plastic, polypropylene and polyethylene pipes. They come in different colors and do not need painting; they can be laid in any way - open, hidden or combined.
XLPE pipes
Polyethylene pipes (PE) are used for:
Advantages:
low cost; a light weight; ease of installation; resistance to liquid freezing (if water freezes, the pipes will only stretch a little, and after thawing they will return to their previous size); absorption of noise and vibration during liquid transportation; reliability and long service life (up to 50 years or more) when used in low-temperature systems.Flaws:
low oxygen permeability of single-layer polyethylene pipes, which over a long period of time can lead to corrosion of system elements; reduced service life when used in high-temperature heating systems; instability to ultraviolet (solar) radiation when exposed for a long time.Depending on the production technology, there are 3 main types of PE pipes:
The following materials stand out:
HDPE, PSD and LDPE pipes are manufactured under different pressures, which influence the process of ethylene polymerization (combination of small gas molecules into larger macromolecules).
PEX and PERT are made from HDPE and PSD using the “cross-linking” and “adhesion” technology.
Cross-linked polyethylene is produced from high-density polyethylene by chemically or physically cross-linking its molecules with molecules of “flat” butene.
During the production of heat-resistant PERT, medium-density polyethylene molecules bond with “bulk” octene.
Despite these differences, PEX and PERT materials have similar properties. Therefore, it is no coincidence that manufacturers lump them into one category (for example, you may see PEX and PERT pipes in the same section on plumbing company websites).
PEX and PERT pipes are:
In cross-section, multilayer pipes represent a three-layer or five-layer structure.
In a three-layer pipe, a layer of polyethylene is covered with glue, on top of which an anti-diffusion layer is applied, which prevents the penetration of oxygen and other gases into the water and thereby has an “anti-corrosion effect.” Polyvinylethylene EVOH or ethylene vinyl alcohol EVAL acts as an “oxygen barrier” that extends the service life of the system.
In a five-layer pipe, the anti-diffusion layer in the center is covered with layers of glue, on top of which layers of polyethylene are applied.
When choosing new pipes, pay attention to the size of the old ones. To replace it, you need to select a product of the same or slightly larger diameter.
For example, on your still functioning metal pipes it says “DN 15”: the number in this case means the internal diameter. And on modern polyethylene pipes, manufacturers indicate outside diameter and wall thickness.
To calculate the internal diameter, you need to subtract the wall thickness multiplied by two from the size of the external diameter. For example, the plastic says 20x2.0. 20 – 4 (2.0x2) = 16 mm. This means that a polyethylene pipe 20x2.0 with an internal diameter of 16 mm is suitable for replacement steel pipe DN 15.
To choose quality products, pay attention to the type of material (indicated on the pipes themselves, the label or in the product description on the website).
There are two types of PERT material – Type I and II. Type 2 PERT can withstand 20% higher pressure than the previous generation, i.e. Type I.
When comparing PEX and PERT, PEX is considered more durable because it resists longer high temperatures and pressure.
Usually the letters a, b or c are added to the PEX inscription, which indicates the method of cross-linking polyethylene and affects their quality. PEXa and PEXb are manufactured chemically, PEXc – physical, while the degree of crosslinking of PEXa reaches 75%, PEXb – 65%, PEXc – 60%. Tests of the last three types of polyethylene pipes of the same size at a temperature of 90°C showed the advantage of PEXb.
In addition, the quality of the pipe depends on the thickness of its wall and the method of applying oxygen-impermeable layers.
Tests have shown that a three-layer pipe is more reliable than a five-layer pipe. In a three-layer pipe, the polyethylene layer is monolithic over the entire cross-section of the pipe; in a five-layer pipe, it is interrupted by an anti-diffusion layer and glue, due to which the intermolecular bonds of polyethylene are interrupted. If it overheats construction hairdryer delamination is possible during bending. The hardness of the EVOH layer is significantly higher than that of PEX, so if properly transported, damage and abrasion of the outer layer is unlikely.
| Manufacturer | Valtec | Pro Aqua | Rehau | Birpex | Royal Thermo | Uponor | TEBO technics | Sanha |
| Polyethylene material | PEXb, PERT type II | PERT type II, PEXa | PEXa | PEXb, PERT | PEXb, PERT type II | PEXa | PERT type II | PEXc |
| Number of layers, pcs | 1-3 | 1-5 | 1-3 | no data | 5 | 1-3 | 1-5 | 5 |
| Outer diameter, mm | 16-20 | 16-40 | 10,1-63 | 16-63 | 16-20 | 16-110 | 16-26 | 16-20 |
| Wall thickness, mm | 2 | 2,2-5,5 | 1,1-8,6 | 1,8-8,6 | 2,2 | 2-15,1 | 2-3 | 2 |
| Working pressure, bar | 6-10 | 6-10 | 8-10 | 6-10 | 10 | 6-10 | 10 | 6 |
| Maximum operating temperature, °C | 80-90 | 90 | 70-95 | 80-95 | 95 | 95 | 95 | 95 |
| Manufacturer country | Italy-Russia | Germany | Germany | Russia | Russia-Italy | Finland | Türkiye | Germany |
| Service life, years | 50 | 50 | 50 | 50 | 50 | 50 | 50 | 50 |
| Manufacturer's warranty, years | 10 | 10 | 1 | 5 | 8-10 | 10 | 7 | 1 |
| Delivery method | bays | bays | bays | bays | bays | bays | bays mi | bays |
| Price per 1 linear meter, rub. | from 33 | from 26 | from 96 | from 43 | From63 | from 52 | from 68 | from 28 |
*Prices according to online sources are valid for February 2018.
To assess the applicability of pipelines to a specific system, pay attention to the declared operating classes of products according to GOST (and certificates of compliance with them). They will show the share of the influence of those changing in summer and winter periods temperatures for the actual service life. Example:
| Operating class | T slave, °C | Time at T pa b, year | T max, °C | Time at T max, year | T avar,°C | Time at T emergency, h | Application area |
| 1 | 60 | 49 | 80 | 1 | 95 | 100 | Hot water supply (60 °C) |
| 2 | 70 | 49 | 80 | 1 | 95 | 100 | Hot water supply (70 °C) |
| 3 | 30 | 20 | Low temperature underfloor heating |
||||
| 40 | 25 | 50 | 4,5 | 65 | 100 | ||
| 4 | 20 | 2,5 | High temperature underfloor heating Low temperature heating with heating devices |
||||
| 40 | 20 | 70 | 2,5 | 100 | 100 | ||
| 60 | 25 | ||||||
| 5 | 20 | 14 | High temperature heating with heating devices | ||||
| 60 | 25 | 90 | 1 | 100 | 100 | ||
| 80 | 10 | ||||||
| HV | 20 | 50 | - | - | - | - | Cold water supply |
The following notations are used in the table:
T slave - operating temperature or combination of temperatures of transported water, determined by the area of application;
T max - maximum operating temperature, the effect of which is limited in time;
T emergency - emergency temperature that occurs in emergency situations in case of violation of regulatory systems.There are three main ways to install wiring:
With hidden installation, the pipeline and all connections are “hidden” in special recesses - grooves. Only fittings (connectors) and bends for connecting plumbing fixtures are visible from the outside. Upon completion of the work, the surface is sealed with finishing materials.
This method protects pipes from accidental damage and preserves aesthetic appearance interior However, this same installation option complicates the process (due to gating - laying channels), increases the cost of work and is not suitable for load-bearing walls.
TO hidden installation This also includes covering pipes with concrete screed in “warm floor” systems.
If the pipes cannot be hidden in the wall (for example, after a recent renovation), they can be laid on the surface. This option is convenient for visual inspection of connections and allows you to quickly clean the area or replace a component if necessary. Additional arguments in favor of the method are the ease and low cost of work.
The combined method involves laying unfinished walls on the surface, which are then covered with plasterboard boxes or false panels made of plastic, tiles or other materials.
For installation, one of two connection systems is usually used:
At sequential system the pipe is laid from one object to another. This system is suitable for bathrooms with a minimum number of objects (bathtub, sink, washing machine).
IN collector system all control devices are located in a compact manifold, which is placed in a special cabinet. Using a collector simplifies the work process and saves money. Suitable for radiator wiring and underfloor heating.
Tips for installing polyethylene pipes
Installation tips:
Before starting work, consider how the pipes will be placed. Then, directly on the walls, floor or ceiling, use a pencil or marker to draw the lines of the future pipeline. Use the pipe connection to the faucet, radiator or manifold as a starting point.
If necessary, before concealed installation, insulate the fittings with film or the entire pipes with a special corrugated casing. Do not use sharp objects to unpack the coil, as they may damage the material.
Try to minimize the number of fittings that affect pressure stability. For convenience, during the installation of “warm floors” you can use special slabs or mats that facilitate installation and minimize heat loss.
If you decide not to use heat insulating mats, use anchor brackets and 90°C rotation clamps, since the “molecular memory” of polyethylene pipes will prevent them from maintaining the specified shape.
The same memory effect will help restore the original shape of the PEX pipe in case of excessive bending and deformation: it is enough to heat it with a hair dryer to 100–120 ° C (the temperature depends on the material, it is indicated in the product data sheet).
So, you have decided to lay a polyethylene pipeline yourself. In addition to the pipes themselves, you will need:
You can independently install cross-linked polyethylene pipes using three main types of fittings:
The range of all types of fittings includes connectors of various shapes - straight (couplings), elbows, angles, water sockets, tees, crosses, which can be divided into two types:
Because the compression fittings require maintenance, they are perfect for open and combined installation. They are not suitable for installation in walls or heated floors.
Components of a compression fitting:
How to proceed:
The connection of pipes using a sliding sleeve is permanent, so such connectors can be used for any type of pipeline laying, even hidden.
Components for the sliding sleeve:
How to proceed:
Watch video instructions:
Watch video instructions:
In the online store Santekhmontazh.rf you can buy pipes made of cross-linked polyethylene from PEXb and PERT (type 2) of the Russian-Italian brand VALTEC and the German ProAqua. They are adapted to the conditions of domestic heat and water supply systems and have a 10-year manufacturer’s warranty. ProAqua products have undergone comprehensive testing and are certified in accordance with Russian standards. VALTEC sanitary ware received the “Brand of the Year” award in the Russian Federation and is widely in demand in the country (in the Moscow region alone, more than 1,200,000 sq. m of residential space are equipped with it every year).
In addition to polyethylene pipes, you can purchase from us fittings, fasteners and tools for their installation, heat-insulating boards, manifold cabinets, blocks, etc.
We will help you select all the necessary plumbing equipment to suit your needs, and we will also quickly and professionally install it, if after reading this article you still do not dare to change or lay the pipeline system yourself. Our installation department specializes in laying engineering systems in private and apartment buildings, in non-residential buildings for various purposes.
PE-RT is a modern and universal polymer material, characterized by a large margin of strength and high resistance to temperature influences. Pipes made of PE-RT type 2 can be used for heating, cold and hot water supply. They are also widely used to protect power supply and communication cables. Compared to other types of polyethylene pipes, products made from PE-RT type 2 have the following advantages:
Most wide range operating temperatures. Acceptable constant temperature coolant 95°C. At the same time, flexibility is maintained at sub-zero temperatures, down to -50°C, which eliminates the formation of cracks during storage and transportation in winter time. When the water inside freezes, the pipes are also not damaged; after defrosting, they retain their original shape.
Resistant to corrosion and chemical attack. Pipes made of PE-RT are not affected by hard water and can withstand acidic and alkaline environments. Deposits do not form on the walls of polyethylene pipes, reducing throughput.
Flexibility and resilience. Pipes of small diameters are suitable for hidden wiring and can be concreted. PE-RT pipes with a diameter of up to 110 mm inclusive can be supplied in coils, which allows such pipes to be laid using the trenchless method, as well as inside old metal pipelines without dismantling them.
High operating pressure. For pipes with sufficient wall thickness, the nominal operating pressure is 16 atmospheres at a temperature of the transmitted medium up to 95°C. Thin-walled pipes are designed for constant pressure up to 10 atmospheres.
Fast installation. The length of the section in the bay allows you to do without intermediate connections. This also reduces the amount of waste.
Low thermal conductivity allows minimizing heat loss in heating networks.
Reliable connection. Pipes made of PE-RT can be welded in the same way as any other polyethylene pipes - end-to-end or using electric welded fittings.
Type II PE-RT pipes are often used for cable installation. In this case, they can be used as standard pipes, and pipes specially designed for this purpose with an additional protective layer.
Manufacturers offer several options for pipes designed for laying power, telecommunications and signal cables, as well as fiber optic lines. For example, the Tekhstroy company produces a series of TEHSTROY TR (temperature resistant) pipes made of polyethylene with increased heat resistance. High resistance to temperature fluctuations allows the pipe to be laid at any depth, including above the soil freezing depth. Operating temperature ranges from -20°C to +95°C.
The TEHSTROY TR series includes single-layer pipes with a nominal outer diameter Dn and pipes with an additional protective layer, sold under the brand Technical Construction TR-1 Prosafe. The protective shell, made of thermoplastic polymer, may have a red or green color. Both types of pipes are available in diameters from 16 to 630 mm, which allows you to choose the optimal size for both mains and single signal and communication lines.
The use of pipes with a protective layer allows pipelines to be laid directly into the ground, as well as along the bottom of reservoirs with or without burial into the ground. Using the HDD method often reduces installation costs, since it does not require excavation work and greatly reduces the number of joints.
Today, Uponor pipes made of cross-linked polyethylene are widely used in the organization of cold and hot water supply systems, as well as heating, including floor heating, and snow melting systems. They form a special class among other polymer pipes. Uponor pipes are the result of 35 developments aimed at creating particularly strong and reliable pipes.
Uponor pipes are produced using PE-Xa technology - under high pressure and temperature, as well as exposure to organic peroxide, cross-link polyethylene macromolecules to form Carbon-Carbon cross-links. In this case, a strong and elastic three-dimensional structure is formed, which provides the products with high resistance to thermal and mechanical stress.
Uponor PE-Xa pipes can restore their original shape, as they have a “thermal memory” effect. In addition, the pipes are coated with an anti-diffusion coating, which prevents the risk of corrosion. Pipes have the following advantages:
Thanks to the advantages of PE-Xa pipe storm drain Uponor will last a very long time.
The Santekhkomplekt company offers a wide range of pipes of various diameters, supplied in coils, as well as fittings for them. Uponor products are impeccable quality and reliability.
Thanks to the special fitting system (Quick&Easy), you will receive a system completely ready for installation. Installation using press fittings allows you to achieve amazing reliability of connections.
XLPE pipes PEX-a are presented by the Finnish concern Uponor. PEX-a pipes have a wide range of applications; the evalPEX line is intended for radiator heating systems. The advantages of this type of pipe are high resistance to temperatures in the range from -100°C to +110°C, molecular shape memory, low thermal conductivity, simplicity and ease of installation, high elasticity, silent operation, resistance to chemicals.
The safety of cross-linked polyethylene pipes is confirmed by an international eco-certificate. The pipes are designed for a pressure of 6 bar. Our catalog contains EVAL PEX-a pipes with a diameter of 16, 20, 25, 32, 75, 90 mm in coils of various sizes.
Polyethylene pipes have many advantages, in particular:
Thanks to these advantages, cross-linked polyethylene pipes are widely used in heating systems. At the Santekhkomplekt company you can order high-quality pipes made in Europe (Finland).
Fittings are one of the most important components for supplying water, coolant, etc., since they often have to withstand the heaviest load. The Santekhkomplekt company offers a wide range of brass threaded fittings, as well as PPSU and PE-Xa connecting parts for cross-linked polyethylene pipes. Labor-intensive process Installation with Uponor fittings is simple, fast and convenient.
Connections made from high-strength plastic PPSU, which has proven itself in heating and water supply systems, are resistant to high temperatures (up to +170°C), high impact resistance and resistance to aggressive environments. Along with other plastics, PPSU is not subject to corrosion, and in terms of strength and reliability characteristics it is comparable to metal. Plus, polyphenyl sulfone is UV resistant and not prone to deposits. The result is highly reliable and tight connections, the cost of which is lower than similar metal products.
Uponor offers threaded fittings with a diameter of 16-25 mm and connecting parts with larger diameters - 50-63 mm. The company's use of the most advanced materials guarantees reliable operation and extended service life of both individual pipeline parts and the entire system as a whole.
The number of supporters of home heating according to the "" principle is constantly increasing - it has proven its high efficiency and convenience. Indeed, a properly planned, competently installed and well-functioning water floor heating system is distinguished by high efficiency, and therefore cost-effectiveness, the most optimal the microclimate created by it - with rising currents of warm air and a comfortable distribution of air temperature along the height. If we add to this the fact that with such heating the floor surface acts as a heat exchanger, and there are simply no radiators that do not fit well into the interior, then the growing popularity of this type of room heating receives a complete logical explanation.
Accordingly, the number of home owners who are seriously considering a complete transition to water underfloor heating is increasing. However, it should be noted that this is a rather complex and very large-scale undertaking. In addition to the difficulties with conducting construction work, it is necessary to correctly calculate and select heating equipment, distribution fittings, special instruments and devices for monitoring, control and safety. And finally, very important point are, in fact, the pipes for the warm water floor. These components of such a heating system must be Special attention, due to the fact that the main load - both thermal and mechanical - falls on them.
This material has a full “bouquet” of all kinds positive qualities. Copper pipes conduct and transfer heat well. This material has excellent ductility along with high mechanical strength. Copper is a very durable metal due to its chemical properties. capable of special features Excellent corrosion resistance. Moreover, in modern pipes the copper walls are also covered with an additional high-strength polymer film - service life similar products are calculated over many decades.
Copper pipe - practically no drawbacks, except for a very high price and installation difficulties The disadvantage is that installation is quite complex, which requires special tools and stable skills to work with it. This greatly limits the possibility of independently creating such a heating system. But, probably, this is not even the main thing - the cost of such pipelines, especially in comparison with polymer ones, is extremely high, and, alas, is affordable to very few.
Corrugated Steel Pipe
And this is probably the only one types of pipes that It is not prohibited to splice along the length of the heating circuit - their fitting connections are considered so reliable.
Such pipes are made from of stainless steel, they bend easily and retain their given position well. Problems of corrosion resistance, high heat transfer mechanical strength they don’t even rise here - such pipes meet these requirements fully. They are given special additional protection by a special coating made of high-quality high-density polyethylene.
Such pipelines, by the way, are actively used in technological lines V chemical industry many developed countries - and this says a lot. And yet they are not yet widely used in private residential construction. The main reasons are high prices and, perhaps, even a lack of information among home owners about such materials.
The production form of corrugated stainless pipes is ready-made sections of various lengths or coils up to 30 or 50 meters long.
Here it is necessary to immediately make one important note. If you read the variety of articles on water pipes used for heating circuits, you will notice one common mistake. The authors divide the variety of flexible pipes into metal-plastic and made from cross-linked polyethylene. From such a presentation, the reader often gets the misconception that metal-plastic products use some kind of ordinary polyethylene, and in addition to this, there is also cross-linked polyethylene. Nothing like this! All types of polyethylene used in modern production technologies have one degree or another of cross-linking. And it will be better to distinguish between pipes using other criteria - based on the polymer processing technology and the structure of the pipe itself.
If you don’t figure this out right away, you can simply get confused in the concepts in the future.
Polyethylene, known to everyone and so popular in the production of many household items, for all its advantages, is still not stable. It has a pronounced linear molecular structure, these “chains” are in no way connected to each other, and even with a slight temperature effect, ordinary polyethylene simply begins to “float”. It cannot be used in products that are subject to thermal stress.
It’s a different matter if the mentioned molecular chains are “stitched” - that is, creating stable numerous cross-links, transforming the linear structure into a three-dimensional one. In this case, the polymer does not lose its properties at all. positive characteristics, and plus it gains stability. The more such intermolecular “bridges” there are, the higher the so-called degree of cross-linking (measured as a percentage), and the better and stronger the resulting material.
Moreover, cross-linked polyethylene has a very unique “memory” property. Products made from it, to a certain extent deformed from mechanical, baric or thermal loads, always tend to return to their original shape once given to them after external influence stops completely or weakens. This is extremely important feature specifically for pipe production.
Cross-linked polyethylene has the accepted designation PEX. Cross-linking, that is, the creation of transverse intermolecular bonds, is technologically carried out in different ways.
Having undergone special processing, cross-linked polyethylene is very widely used for the production of various types of pipes, some of which are quite suitable for creating, and some are even specifically designed for these purposes.
This is where you need to pay special attention to the specific type of polymer used to produce this pipe. As already mentioned, the optimal solution would be PEX pipes, although they are, of course, much more expensive.
There is another one with metal-plastic pipes important nuance– there are too many counterfeit, obvious and low-quality fakes on the building materials market, absolutely unknown manufacturers who do not accompany their products with any documents or guarantees. Therefore, when purchasing metal plastic, you should never be shy - you must be persistent and demand that the products be presented with certificates of quality and compliance with existing standards.
But even quality pipes PEX-Al-PEX are still available significant shortcomings. Thus, the heterogeneity of the wall material, and hence the coefficient of linear expansion of the layers, leads to their delamination over time. The only question is time - but this process is inevitable. Inner layer PEX is forcedly narrowed (to about 0.8 mm), and does not always cope with peak loads (any experienced plumber can tell you about ruptures metal-plastic pipes). At the same time, a thin layer of foil (from 0.2 to 0.4 mm), even with perfect welding, cannot become a barrier to critical pressure.
For their manufacture, PEX-a or PEX-b are used. The pipe wall can have a completely monolithic structure, or be equipped with a special layer of EVON¸ which serves as an oxygen barrier.
These pipes are very convenient to lay out when installing “warm floor” circuits. They have good ductility, which allows installation with a minimum step between adjacent loops.
All leading manufacturers necessarily equip their products with reliable connecting fittings, which makes installation quite simple and an understandable activity.
When choosing any polymer pipes, you need to understand at least a little about the system of their classification and labeling. It may vary slightly depending on the manufacturer, but still basic principles are saved. You can consider it with a specific example.
1- in the first place, the specific model of the pipe and its brand are usually indicated.
2 – outer diameter of the pipe and total thickness of its walls.
3 – special European standards indicating the possibility of using pipes. In this case, this is an indication that the pipe is suitable even for drinking water.
4 – applied technology for quality control of finished products.
5 – polyethylene cross-linking technology (in accordance with Engel classification, which was described above).
6 – compliance of pipe parameters for operating temperature and pressure with European standards DIN 16892/16893. Specific values of operating parameters and service life can be indicated in the accompanying documentation in the form of a plate:
It also happens that these values are applied directly to the pipe body - for example "DIN 16892 PB 12/60 °C PB 11/70 °C PB 9/90 °C".
7—information about the date and time of production, line or machine number, etc.
In addition, this is usually followed by a pipe length mark - every meter. This simplifies both the implementation of pipes and the work with them directly during installation.
A technological breakthrough can probably be considered the emergence of a completely new type of polyethylene in the production of pipes - PE-RT(short for " Polyethylene oof Raised Temperature resistance"—polyethylene with increased heat resistance). By and large, it is not a crosslinking product, and even the initial raw material, granulate, already has the necessary qualities - numerous and stable intermolecular bonds.
This became possible with the development of technologies for controlled processes of spatial formation of macromolecules. Such polymers open up a wide range of possibilities - you can create materials with precisely specified characteristics, focusing on one or another property.
The complex mesh-like structure of the lattice makes it possible to dramatically increase the resistance of the material to external and internal loads, and to cracking during bending. And at the same time, the material, unlike PEX, remains thermoplastic, that is, it can be connected not only using mechanical adapters(fittings), but also using welding, which significantly increases the reliability of joints if necessary.
Polyethylene PE-RT are being used on an ever wider scale, and there is a strong tendency that over time it will completely displace its “stitched brother” - PEX. All this is thanks to a whole “bouquet” of their positive qualities:
Polyethylene is used PE-RT, just like PEX, both for the production of metal-plastic pipes and for purely polymer ones.
In both cases performance characteristics– significantly higher than using cross-linked analogues.
During production polymer pipe without a metal insert, manufacturers often use their own proprietary developments to ensure oxygen impermeability walls For example, this could be an airtight OXYDEX layer, or a special anti-diffusion EVON barrier.
The main operational characteristics of such pipes are given as an example in the following table:
| Index | 16 × 2 mm | 20 × 2 mm |
|---|---|---|
| Volume (l/linear m) | 0.113 | 0.201 |
| Weight (kg/linear m) | 0,071 | 0.127 |
| Minimum bending radius – 5d (mm) | 60 | 100 |
| Temperature (°C) | 20 | 20 |
| Pressure (bar) | 20 | 20 |
| Service life (years) | more than 50 | more than 50 |
| Temperature (°C) | 75 | 75 |
| Pressure (bar) | 10 | 10 |
| Service life (years) | more than 50 | more than 50 |
| Temperature (°C) | 95 | 95 |
| Pressure (bar) | 6 | 6 |
| Service life (years) | more than 50 | more than 50 |
| Ultimate pressure (bar) | 6 | 4.5 |
| at temperature (°C) | 110 | 110 |
| Ultimate pressure (bar) | 11 | 10 |
| at temperature (°C) | 90 | 90 |
| Linear elongation coefficient max at t=95°С (1/°С) | 1.8 1E-4 | 8.2 1E-5 |
| Thermal conductivity coefficient (W/K m) | 0.41 | |
| Roughness inner surface(µm) | 0.125 (Class 10) | |
| Design strength of material (Mpa) | 6.3 |
To summarize what has been said, it can be noted that polyethylene pipes PE-RT today they are probably the material that best meets the requirements of a “warm floor” system, while remaining in the sector of reasonable affordability.
It depends, Firstly, on the length of the heating system circuits. – you can find out by reading the corresponding publication on our portal.
When making calculations, one should not forget about the sections from the floor to the distribution manifold, taking into account the connecting margin of at least 500 mm at each end.
The cost of pipes may depend on the manufacturer, the specific model, and the region where the material is purchased. The products of well-known European companies – “Uponor”, “Rehau”, “Kermi”, “Henco”, “Oventrop” and others - enjoy the greatest authority and, accordingly, demand. For example, the table shows several models of pipes suitable for “warm floors”. Prices are indicative, typical for the central regions of Russia:
| Manufacturer, brand | Diameter, mm | Brief technical specifications | Coil length | Price per 1 linear meter |
|---|---|---|---|---|
| Uponor PEXа evalPEX Q&E 16 x 2.0 | 16 | Cross-linked polyethylene, wall 2 mm, t max – up to 95 degrees, (short-term heating up to 110) | 50 – 240 m | 90 rub |
| Uponor PEXа evalPEX Q&E 20 x 2.0, | 20 | -//- | 50 – 120 m | 114 |
| REHAU "Rautitan stabil" | 16 | Metal plastic, PE-Xc/AI/PE wall 2.6 mm | 100 | 105 |
| REHAU "Rautitan stabil" | 20 | Metal plastic, PE-Xа–AL–PE wall 2.9 mm | 100 | 150 |
| REHAU "Rautitan flex" | 16 | Cross-linked polyethylene RAU-PE-Xa, wall 2.2 mm | 100 | 105 |
| Kermi MKV xnet 16 x 2.0 | 16 | Metal-plastic, PE-Xс–AL–PE–Xс | 100 | 55 |
| REHAU "Rautitan Pink" | 16 | Cross-linked polyethylene RAU-PE-Xa, wall 2.2 mm, t swing - up to 90 degrees | 120 | 64 |
| Wieland cuprotherm CTX | 20 | Copper pipe in a plastic sheath, wall 2 mm | 50 | 240 |
| FLEXSY-20 | 20 | Corrugated Annealed stainless pipe With polymer coating, wall 2 mm | up to 50 | 175 |
| BioPipe PERT 16x2.0 | 16 | Monolayer, t max – up to 100 degrees, pressure – up to 6 bar. | 240 m | 35 |
| Thermotech MultiPipe PE-RT II, 16*2 mm | 16 | Five-layer with diffuse barrier | 240 m | 85 |
The table deliberately does not indicate the most inexpensive types of pipes, from unknown or very dubious manufacturers. It is worth thinking carefully before buying cheap, untrustworthy products, since a water-heated floor system poured with a concrete screed should not cause any reason for concern for the home owner.
And finally, a video assessing pipes for a “warm floor” system from a specialist.
Water pipes
