Withstands temperatures over 1000 ° C.
ROCKWOOL insulation is extremely fire resistant. It helps to localize the fire and prevents its spread. In addition, it does not emit toxic substances and is safe when insulating children's rooms.
Thermal insulation
Save energy by maintaining an optimal indoor temperature and climate.
This makes working and living conditions healthier and more comfortable, improving the quality of life of people - especially in an urban environment. Temperature stability can significantly reduce heating, cooling and ventilation costs and reduce greenhouse gas emissions.
Soundproofing
Isolation, absorption or correction of sound.
The city needs good infrastructure (roads, rail and tram lines, airports), but sometimes it is too noisy. Vibration, traffic noise - not to mention anthropogenic noise pollution - have serious negative consequences for well-being, especially in densely populated areas.
Durability
Improved performance and increased stability at a lower cost.
In cities experiencing a shortage of free land, a growing number of people working and living in high-rise buildings. Such structures can be a brilliant solution to the problem of providing a growing population with safe and durable housing.
Aesthetics
A harmonious combination of performance and aesthetic qualities.
When people live or work in a beautiful environment, it enhances their comfort and motivation. An environment in which people spend time with pleasure strengthens social bonds and makes the surrounding area a safer and more conducive place to live.
Water resistant
Manage your most valuable resource efficiently.
Traditional food production methods are losing ground in the face of population growth and climate change is increasing the need for flood protection. Stone wool products can be designed to absorb or repel water as needed, and can also be used to recirculate water in greenhouses to help solve a variety of water management challenges.
Sustainability
Sustainable ROCKWOOL products reveal the power and naturalness of natural stone.
Stone is one of the most common materials on earth; however, we must make better use of our planet's resources. We have developed technologies that make it possible to use waste from other industrial sectors as an alternative raw material.
In the practice of private construction, it is not so often, but still there are situations when heating communications are required not only to be diluted across the premises of the main house, but also to be extended to other nearby buildings. These can be residential outhouses, outbuildings, summer kitchens, household or agricultural buildings, for example, used to keep pets or birds. The option is not excluded when, on the contrary, the autonomous boiler room itself is located in a separate building, at some distance from the main residential building. It happens that the house is connected to a central heating main, from which pipes are drawn to it.
Heating pipes can be laid between buildings in two ways - underground (channel or channelless) and open. The process of installing a local heating main above the ground seems to be less laborious, and this option is often resorted to in conditions of independent construction. One of the main conditions for the efficiency of the system is a correctly planned and well-executed thermal insulation for outdoor heating pipes. It is this issue that will be addressed in this publication.
What is pipe insulation for and the basic requirements for it?
It would seem nonsense - why insulate the already almost always hot pipes of the heating system? Perhaps someone can be misled by a kind of "play on words." In this case, of course, it will be more correct to conduct a conversation in terms of "thermal insulation".
Thermal insulation work on any pipelines has two main goals:
- If pipes are used in heating or hot water supply systems, then the reduction of heat losses, maintaining the required temperature of the pumped liquid, comes to the fore. The same principle is also true for industrial or laboratory installations, where the technology requires maintaining a certain temperature of the substance transmitted through the pipes.
- For pipelines of cold water supply or sewer communications, the main factor is precisely insulation, that is, preventing the temperature in the pipes from falling below the critical mark, preventing freezing, leading to the failure of the system and deformation of the pipes.
By the way, such a precautionary measure is required both for heating mains and for hot water pipes - no one is completely insured against emergencies on boiler equipment.
The very cylindrical shape of the pipes predetermines a very large area of \u200b\u200bconstant heat exchange with the environment, which means significant heat loss. And they naturally grow as the diameter of the pipeline increases. The table below clearly shows how the amount of heat loss changes depending on the temperature difference inside and outside the pipe (column Δt °), on the diameter of the pipes and on the thickness of the thermal insulation layer (the data are given taking into account the use of an insulation material with an average coefficient of thermal conductivity λ \u003d 0.04 W / m × ° C).
| Thermal insulation layer thickness. mm | Δt. ° С | Pipeline outer diameter (mm) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 150 | ||
| The amount of heat loss (per 1 running meter of the pipeline. W). | |||||||||||
| 10 | 20 | 7.2 | 8.4 | 10 | 12 | 13.4 | 16.2 | 19 | 23 | 29 | 41 |
| 30 | 10.7 | 12.6 | 15 | 18 | 20.2 | 24.4 | 29 | 34 | 43 | 61 | |
| 40 | 14.3 | 16.8 | 20 | 24 | 26.8 | 32.5 | 38 | 45 | 57 | 81 | |
| 60 | 21.5 | 25.2 | 30 | 36 | 40.2 | 48.7 | 58 | 68 | 86 | 122 | |
| 20 | 20 | 4.6 | 5.3 | 6.1 | 7.2 | 7.9 | 9.4 | 11 | 13 | 16 | 22 |
| 30 | 6.8 | 7.9 | 9.1 | 10.8 | 11.9 | 14.2 | 16 | 19 | 24 | 33 | |
| 40 | 9.1 | 10.6 | 12.2 | 14.4 | 15.8 | 18.8 | 22 | 25 | 32 | 44 | |
| 60 | 13.6 | 15.7 | 18.2 | 21.6 | 23.9 | 28.2 | 33 | 38 | 48 | 67 | |
| 30 | 20 | 3.6 | 4.1 | 4.7 | 5.5 | 6 | 7 | 8 | 9 | 11 | 16 |
| 30 | 5.4 | 6.1 | 7.1 | 8.2 | 9 | 10.6 | 12 | 14 | 17 | 24 | |
| 40 | 7.3 | 8.31 | 9.5 | 10.9 | 12 | 14 | 16 | 19 | 23 | 31 | |
| 60 | 10.9 | 12.4 | 14.2 | 16.4 | 18 | 21 | 24 | 28 | 34 | 47 | |
| 40 | 20 | 3.1 | 3.5 | 4 | 4.6 | 4.9 | 5.8 | 7 | 8 | 9 | 12 |
| 30 | 4.7 | 5.3 | 6 | 6.8 | 7.4 | 8.6 | 10 | 11 | 14 | 19 | |
| 40 | 6.2 | 7.1 | 7.9 | 9.1 | 10 | 11.5 | 13 | 15 | 18 | 25 | |
| 60 | 9.4 | 10.6 | 12 | 13.7 | 14.9 | 17.3 | 20 | 22 | 27 | 37 | |
As the thickness of the insulation layer increases, the overall heat loss rate decreases. However, please note that even a sufficiently thick layer of 40 mm does not completely exclude heat loss. There is only one conclusion - it is necessary to strive to use insulation materials with the lowest possible coefficient of thermal conductivity - this is one of the main requirements for thermal insulation of pipelines.
Sometimes a pipeline heating system is required!
When laying water or sewer lines, it happens that due to the peculiarities of the local climate or the specific installation conditions, thermal insulation alone is clearly not enough. We have to resort to forced installation of heating cables - this topic is discussed in more detail in a special publication of our portal.
- The material used for thermal insulation of pipes, if possible, should have hydrophobic qualities. There will be little current from a heater soaked in water - it will not prevent heat loss, and will soon collapse under the influence of negative temperatures.
- The thermal insulation structure must have reliable external protection. First, it needs protection from atmospheric moisture, especially if a heater is used that can actively absorb water. Secondly, materials should be protected from exposure to the ultraviolet spectrum of sunlight, which has a detrimental effect on them. Thirdly, one should not forget about the wind load, which can violate the integrity of the thermal insulation. And, fourthly, there remains a factor of external mechanical impact, unintentional, including from animals, or due to banal manifestations of vandalism.
In addition, for any owner of a private house, for sure, the moments of the aesthetic appearance of the laid heating main are not indifferent.
- Any thermal insulation material used on heating mains must have a range of operating temperatures corresponding to the real conditions of use.
- An important requirement for the insulation material and its external cladding is the durability of use. No one wants to go back to the problems of thermal insulation of pipes, even once every few years.
- From a practical point of view, one of the main requirements is the ease of installation of thermal insulation, and in any position and in any difficult area. Fortunately, in this regard, manufacturers do not tire of delighting in easy-to-use developments.
- An important requirement for thermal insulation is that its materials must themselves be chemically inert, and not enter into any reactions with the pipe surface. Such compatibility is the key to long-term trouble-free operation.
The cost issue is also very important. But in this regard, the range of prices for specialized ones is very large.
What materials are used for insulating overhead heating mains
The choice of thermal insulation materials for heating pipes with their external laying is quite large. They are of roll type or in the form of mats, they can be given a cylindrical or other figured shape convenient for installation, there are heaters that are applied in liquid form and acquire their properties only after hardening.
Warming with polyethylene foam
Foamed polyethylene is rightly referred to as a very effective thermal insulator. And what is also very important, the cost of this material is one of the lowest.
The thermal conductivity coefficient of polyethylene foam is usually in the region of 0.035 W / m × ° C - this is a very good indicator. The smallest bubbles, isolated from each other, filled with gas, create an elastic structure, and with such a material, if its rolled version is purchased, it is very convenient to work on pipe sections that are complex in configuration.
Such a structure becomes a reliable barrier to moisture - with proper installation, neither water nor water vapor can penetrate through it to the pipe walls.
The density of polyethylene foam is low (about 30 - 35 kg / m³), \u200b\u200band thermal insulation will not make the pipes heavier.
With some assumption, the material can be classified as low-hazard in terms of flammability - it usually belongs to the G-2 class, that is, it is very difficult to ignite, and without an external flame it quickly dies out. Moreover, combustion products, unlike many other thermal insulators, do not pose any serious toxic hazard to humans.
Rolled polyethylene foam for insulation of external heating mains will be both inconvenient and unprofitable - you will have to wind it in several layers in order to achieve the required thickness of thermal insulation. It is much more convenient to work with the material in the form of sleeves (cylinders), in which an internal channel is provided, corresponding to the diameter of the insulated pipe. To put on pipes, an incision is usually made along the length of the cylinder on the wall, which, after installation, can be sealed with reliable tape.
Putting insulation on the pipe is easy A more effective type of polyethylene foam is penofol, which has one on one side. This shiny coating becomes a kind of thermal reflector, which significantly increases the insulating qualities of the material. In addition, it is an additional barrier against moisture penetration.
Penofol can also be of roll type or in the form of shaped cylindrical elements - especially for thermal insulation of pipes for various purposes.
And all the foamed polyethylene for thermal insulation of heating mains is used infrequently. Rather, it is suitable for other communications. The reason for this is the rather low operating temperature range. So. if you look at the physical characteristics, then the upper limit balances somewhere on the brink of 75 ÷ 85 degrees - higher, structural disturbances and the appearance of deformations are possible. For autonomous heating, most often, such a temperature is enough, however, on the verge, and for central heating, heat resistance is clearly not enough.
Insulation elements from expanded polystyrene
The well-known expanded polystyrene (in everyday life it is more often called polystyrene) is very widely used for various types of thermal insulation work. Insulation of pipes is no exception - for this, special parts are made from foam.
Usually these are half-cylinders (for pipes of large diameters, there can be segments of one third of the circumference, 120 ° each), which are equipped with a tongue-and-groove joint for assembly into a single structure. This configuration allows completely, over the entire surface of the pipe, to provide reliable thermal insulation, without remaining "cold bridges".
In everyday speech, such details are called "shells" - for their obvious resemblance to it. Many types are produced, for different external diameters of insulated pipes and different thicknesses of the thermal insulation layer. Usually the length of the parts is 1000 or 2000 mm.
For the production of polystyrene foam type PSB-S of various brands - from PSB-S-15 to PSB-S-35. The main parameters of this material are shown in the table below:
| Estimated material parameters | Expanded polystyrene brand | ||||
|---|---|---|---|---|---|
| PSB-S-15U | PSB-S-15 | PSB-S-25 | PSB-S-35 | PSB-S-50 | |
| Density (kg / m³) | to 10 | up to 15 | 15.1 ÷ 25 | 25.1 ÷ 35 | 35.1 ÷ 50 |
| Compressive strength at 10% linear deformation (MPa, not less) | 0.05 | 0.06 | 0.08 | 0.16 | 0.2 |
| Flexural strength (MPa, not less) | 0.08 | 0.12 | 0.17 | 0.36 | 0.35 |
| Dry thermal conductivity at 25 ° C (W / (m × ° K)) | 0,043 | 0,042 | 0,039 | 0,037 | 0,036 |
| Water absorption in 24 hours (% by volume, no more) | 3 | 2 | 2 | 2 | 2 |
| Humidity (%, no more) | 2.4 | 2.4 | 2.4 | 2.4 | 2.4 |
The advantages of foam as an insulation material have long been known:
- It has a low thermal conductivity coefficient.
- The low weight of the material greatly simplifies the insulation work, for which no special mechanisms or devices are required.
- The material is biologically inert - it will not be a breeding ground for mold or mildew.
- Moisture absorption is negligible.
- The material is easy to cut, adjust to the desired size.
- Polyfoam is chemically inert, absolutely safe for pipe walls, no matter what material they are made of.
- One of the key advantages is that polystyrene is one of the most inexpensive insulation materials.
However, it also has many disadvantages:
- First of all, it is a low level of fire safety. The material cannot be called non-flammable and does not spread flame. That is why, when using it for insulating ground pipelines, fire breaks should be left behind.
- The material does not have elasticity, and it is convenient to use it only on straight pipe sections. True, you can also find special curly details.
- Polyfoam is not a durable material - it is easily destructible under external influences. Ultraviolet radiation also affects it negatively. In short, the above-ground sections of the pipe, insulated with a polystyrene foam shell, will definitely require additional protection in the form of a metal casing.
Usually, in stores where foam shells are sold, galvanized sheets are also offered, cut to the desired size, corresponding to the diameter of the insulation. An aluminum sheath can also be used, although it is certainly much more expensive. The sheets can be fixed with self-tapping screws or clamps - the resulting casing will simultaneously create anti-vandal, windproof, waterproofing protection and a barrier from sunlight.
- And yet even this is not the main thing. The upper limit of normal operating temperatures is only around 75 ° C, after which linear and spatial deformation of parts can begin. Whatever one may say, this value may not be enough for heating. It probably makes sense to look for a more reliable option.
Thermal insulation of pipes with mineral wool or products based on it
The most "ancient" method of thermal insulation of external pipelines is with the use of mineral wool. By the way, it is the most budgetary one, if there is no way to purchase a foam shell.
For thermal insulation of pipelines, various types of mineral wool are used - glass wool, stone (basalt) and slag. Slag is the least preferable: it, firstly, absorbs moisture most actively, and secondly, its residual acidity can very destructively affect steel pipes. Even the cheapness of this cotton wool does not in the least justify the risks of its use.
But mineral wool based on basalt or glass fibers will do the trick. It has good indicators of thermal resistance to heat transfer, high chemical resistance, the material is elastic, and it is easy to lay it even on difficult sections of pipelines. Another advantage is that you can, in principle, be completely calm in terms of fire safety. It is almost impossible to heat up mineral wool to the degree of flammability in the conditions of an outdoor heating main. Even exposure to an open flame will not cause the fire to spread. That is why mineral wool is used to fill fire gaps when using other pipe insulation.
The main disadvantage of mineral wool is its high water absorption (basalt is less susceptible to this "ailment"). This means that any pipeline will require mandatory protection from moisture. In addition, the structure of the cotton wool is not resistant to mechanical stress, it is easily destroyed, and it should be protected with a durable casing.
Usually, a strong plastic film is used, with which a layer of insulation is reliably wrapped, with a mandatory overlap of the strips by 400 ÷ 500 mm, and then all this is closed on top with metal sheets - just by analogy with a polystyrene foam shell. Roofing material can also be used as waterproofing - in this case, 100 ÷ 150 mm of overlap of one strip on another will be enough.
The existing GOSTs determine the thickness of protective metal coatings for open sections of pipelines for any type of thermal insulation materials used:
| Covering material | Minimum metal thickness, with the outer diameter of the insulation | ||
|---|---|---|---|
| 350 and less | Over 350 and up to 600 | Over 600 and up to 1600 | |
| Stainless tapes and sheets | 0.5 | 0.5 | 0.8 |
| Sheet steel sheets, galvanized or polymer coated | 0.5 | 0.8 | 0.8 |
| Aluminum or aluminum alloy sheets | 0.3 | 0.5 | 0.8 |
| Aluminum or aluminum alloy strips | 0.25 | - | - |
Thus, despite the seemingly inexpensive price of the insulation itself, its full-fledged installation will require considerable additional costs.
Mineral wool for insulation of pipelines can also act in a different capacity - it serves as a material for the manufacture of finished thermal insulating parts, by analogy with polyethylene foam cylinders. Moreover, such products are produced both for straight sections of pipelines and for bends, tees, etc.
Usually, such insulation parts are made of the most dense - basalt mineral wool, have an outer foil coating, which immediately removes the problem of waterproofing and increases the efficiency of insulation. But you still can't get away from the outer casing - a thin layer of foil won't protect you from accidental or intentional mechanical stress.
Thermal insulation of heating mains with polyurethane foam
One of the most effective and safe to use modern insulation materials is polyurethane foam. He has a lot of all sorts of advantages, so the material is used on almost any structure that requires reliable insulation.
What are the features of polyurethane foam - insulation?
Polyurethane foam for pipeline insulation can be used in various forms.
- Foam shells are widely used, usually with an outer foil coating. It can be collapsible, consisting of half-cylinders with tongue-and-groove locks, or, for pipes of small diameter, with a cut along the length and a special valve with a self-adhesive back surface, which greatly simplifies the installation of insulation.
- Another method of thermal insulation of a heating main with polyurethane foam is to spray it in liquid form using special equipment. The resulting layer of foam, after complete hardening, becomes an excellent insulation. This technology is especially convenient at complex junctions, pipe bends, in nodes with shut-off and control valves, etc.
The advantage of this technology is also that due to the excellent adhesion of polyurethane foam spraying to the pipe surface, excellent waterproofing and anti-corrosion protection are created. True, the polyurethane foam itself also requires mandatory protection - from ultraviolet rays, so again it will not be possible to do without a casing.
- Well, if a sufficiently long heating main is required, then, probably, the most optimal choice would be the use of pre-insulated (pre-insulated) pipes.
In fact, such pipes are a multi-layer structure assembled at the factory:
- The inner layer is, in fact, the steel pipe of the required diameter itself, through which the coolant is pumped.
- The outer cover is protective. It can be polymeric (for laying a heating main in the soil) or metal galvanized - what is required for open sections of the pipeline.
- A monolithic, seamless layer of polyurethane foam is poured between the pipe and the casing, which serves as an effective thermal insulation.
On both ends of the pipe, an assembly area was left for welding during the assembly of the heating main. Its length is calculated in such a way that the heat flux from the welding arc will not damage the polyurethane foam layer.
After installation, the remaining non-insulated areas are primed, covered with polyurethane foam shell, and then with metal belts, comparing the coating with the common outer casing of the pipe. Often, it is in such areas that fire breaks are organized - they are densely filled with mineral wool, then they are waterproofed with roofing material and are still covered from above with a steel or aluminum casing.
The standards set a certain range of such sandwich pipes, that is, it is possible to purchase products of the required nominal diameter with optimal (normal or reinforced) thermal insulation.
| Outside diameter of steel pipe and minimum wall thickness (mm) | Dimensions of the sheath made of galvanized sheet steel | Estimated thickness of the thermal insulation layer of polyurethane foam (mm) | |
|---|---|---|---|
| nominal outer diameter (mm) | minimum thickness of steel sheet (mm) | ||
| 32 × 3.0 | 100; 125; 140 | 0.55 | 46,0; 53,5 |
| 38 × 3.0 | 125; 140 | 0.55 | 43,0; 50,5 |
| 45 × 3.0 | 125; 140 | 0.55 | 39,5; 47,0 |
| 57 × 3.0 | 140 | 0.55 | 40.9 |
| 76 × 3.0 | 160 | 0.55 | 41.4 |
| 89 × 4.0 | 180 | 0.6 | 44.9 |
| 108 × 4.0 | 200 | 0.6 | 45.4 |
| 133 × 4.0 | 225 | 0.6 | 45.4 |
| 159 × 4.5 | 250 | 0.7 | 44.8 |
| 219 × 6.0 | 315 | 0.7 | 47.3 |
| 273 × 7.0 | 400 | 0.8 | 62.7 |
| 325 × 7.0 | 450 | 0.8 | 61.7 |
Manufacturers offer such sandwich pipes not only for straight sections, but also for tees, bends, expansion joints, etc.
The cost of such pre-insulated pipes is quite high, but with their purchase and installation, a whole range of problems are solved at once. So these costs seem to be quite justified.
Video: production process for pre-insulated pipes
Insulation - foamed rubber
Thermal insulating materials and products made of synthetic foam rubber have recently become very popular. This material has a number of advantages that bring it to a leading position in the issues of pipeline insulation, including not only heating mains, but also more responsible ones - on complex technological lines, in mechanical engineering, aircraft and shipbuilding:
- Foamed rubber is very flexible, but at the same time has a large margin of tensile strength.
- The density of the material is only 40 to 80 kg / m³.
- The low coefficient of thermal conductivity provides very effective thermal insulation.
- The material does not shrink over time, completely retaining its original shape and volume.
- Foamed rubber is flame retardant and self-extinguishing.
- The material is chemically and biologically inert; no foci of mold or mildew, no insect nests or
- The most important quality is almost absolute water and vapor resistance. Thus, the insulation layer immediately becomes an excellent waterproofing for the pipe surface.
Such thermal insulation can be produced in the form of hollow tubes with an inner diameter from 6 to 160 mm and a layer of insulation from 6 to 32 mm, or in the form of sheets, which are often given the function of "self-adhesive" on one side.
| The name of indicators | The values |
|---|---|
| Length of finished tubes, mm: | 1000 or 2000 |
| Colour | black or silver, depending on the type of protective coating |
| Application temperature range: | from - 50 to + 110 ° С |
| Thermal conductivity, W / (m × ° С): | λ≤0.036 at a temperature of 0 ° С |
| λ≤0.039 at a temperature of + 40 ° С | |
| Vapor permeation resistance coefficient: | μ≥7000 |
| Fire hazard | Group G1 |
| Allowable change in length: | ± 1.5% |
But for heating mains located in the open air, ready-made insulation elements made using the Armaflex ACE technology with a special protective coating ArmaChek are especially convenient.
ArmaChek coating can be of several types, for example:
- "Arma-Chek Silver" is a multilayer PVC-based casing with a reflective silver coating. This coating provides excellent protection of the insulation from both mechanical stress and ultraviolet rays.
- The black Arma-Chek D coating has a high strength fiberglass backing that retains excellent flexibility. This is an excellent protection against all possible chemical, weather, mechanical influences, which will keep the heating pipe intact.
Usually, such products using the ArmaChek technology have self-adhesive valves, which hermetically “seal” the insulation cylinder on the pipe body. Curly elements are also produced, allowing installation on difficult sections of the heating main. Skillful use of such thermal insulation allows you to quickly and reliably install it without resorting to creating an additional external protective casing - there is simply no need for it.
Probably, the only thing that hinders the widespread use of such thermal insulation products for pipelines is the still prohibitively high price for real, "branded" products.
Prices for thermal insulation for pipes
Thermal insulation for pipes
A new direction in insulation - thermal insulation paint
Another modern insulation technology cannot be missed. And it is all the more pleasant to talk about it, since it is the development of Russian scientists. We are talking about a ceramic liquid insulation, which is also known as thermal insulation paint.
This is, without any doubt, an "alien" from the field of space technology. It is in this scientific and technical industry that the issues of thermal insulation from critically low (in open space) or high (when launching ships and landing descent vehicles) are especially acute.
The thermal insulation qualities of ultra-thin coatings seem fantastic. At the same time, such a coating becomes an excellent waterproofing and vapor barrier, protecting the pipe from all possible external influences. Well, the heating main itself takes on a well-groomed, eye-pleasing look.
The paint itself is a suspension of microscopic vacuum-filled silicone and ceramic capsules suspended in a liquid state in a special composition that includes acrylic, rubber and other components. After application and drying of the composition, a thin elastic film is formed on the pipe surface, which has outstanding thermal insulation properties.
| Indicator names | unit of measurement | The quantity |
|---|---|---|
| Paint color | white (can be changed on request) | |
| Appearance after application and complete hardening | matt, even, uniform surface | |
| Flexural elasticity of the film | mm | 1 |
| Coating adhesion by pull-off force from the painted surface | ||
| - to the concrete surface | MPa | 1.28 |
| - to the brick surface | MPa | 2 |
| - to steel | MPa | 1.2 |
| Coating resistance to temperature drops from -40 ° C to + 80 ° C | without changes | |
| Coating resistance to temperature +200 ° С for 1, 5 hours | no yellowing, cracks, peeling or bubbles | |
| Durability for concrete and metal surfaces in a moderately cold climatic region (Moscow) | years old | not less than 10 |
| Thermal conductivity | W / m ° C | 0,0012 |
| Vapor permeability | mg / m × h × Pa | 0.03 |
| Water absorption in 24 hours | % by volume | 2 |
| Operating temperature range | ° C | from - 60 to + 260 |
Such a coating does not require additional protective layers - it is strong enough to cope with all influences on its own.
Such a liquid insulation is realized in plastic cans (buckets), like ordinary paint. There are several manufacturers, and among the domestic brands "Bronya" and "Korund" can be especially noted.
You can apply such a thermal paint by aerosol spraying or in the usual way - with a roller and a brush. The number of layers depends on the operating conditions of the heating main, the climatic region, the diameter of the pipes, and the average temperature of the pumped heat carrier.
Many experts believe that such heaters will eventually replace the usual thermal insulation materials based on a mineral or organic basis.
Video: presentation of Korund super-thin thermal insulation
Insulation paint prices
Heat insulating paint
What is the thickness of the heating mains insulation required
Summing up the review of the materials used for thermal insulation of heating pipes, you can see the performance indicators of the most popular of them in the table - for clarity of comparison:
| Thermal insulation material or product | Average density in the finished structure, kg / m3 | Thermal conductivity of heat-insulating material (W / (m × ° С)) for surfaces with temperature (° С) | Operating temperature range, ° С | Flammability group | |
|---|---|---|---|---|---|
| 20 and up | 19 and below | ||||
| Broached mineral wool plates | 120 | 0,045 | 0.044 ÷ 0.035 | - 180 to + 450 for mats, on fabric, mesh, fiberglass canvas; up to + 700 - on a metal mesh | Non-flammable |
| 150 | 0,05 | 0.048 ÷ 0.037 | |||
| Thermal insulation boards made of mineral wool on a synthetic binder | 65 | 0.04 | 0.039 ÷ 0.03 | From - 60 to + 400 | Non-flammable |
| 95 | 0,043 | 0.042 ÷ 0.031 | |||
| 120 | 0,044 | 0.043 ÷ 0.032 | From - 180 + 400 | ||
| 180 | 0,052 | 0.051 ÷ 0.038 | |||
| Thermal insulation products from foamed ethylene-polypropylene rubber "Aeroflex" | 60 | 0,034 | 0,033 | From - 55 to + 125 | Low-flammable |
| Mineral wool semi-cylinders and cylinders | 50 | 0,04 | 0.039 ÷ 0.029 | From - 180 to + 400 | Non-flammable |
| 80 | 0,044 | 0.043 ÷ 0.032 | |||
| 100 | 0,049 | 0.048 ÷ 0.036 | |||
| 150 | 0,05 | 0.049 ÷ 0.035 | |||
| 200 | 0,053 | 0.052 ÷ 0.038 | |||
| Thermal insulation cord made of mineral wool | 200 | 0,056 | 0.055 ÷ 0.04 | From - 180 to + 600 depending on the material of the mesh tube | In mesh tubes made of metal wire and glass filament - non-combustible, the rest are slightly combustible |
| Glass staple fiber mats on synthetic binder | 50 | 0,04 | 0.039 ÷ 0.029 | From - 60 to + 180 | Non-flammable |
| 70 | 0,042 | 0.041 ÷ 0.03 | |||
| Superfine glass fiber mats and wadding without binder | 70 | 0,033 | 0.032 ÷ 0.024 | From - 180 to + 400 | Non-flammable |
| Mats and wadding made of super-thin basalt fiber without binder | 80 | 0,032 | 0.031 ÷ 0.024 | From - 180 to + 600 | Non-flammable |
| Perlite sand, expanded, fine | 110 | 0,052 | 0.051 ÷ 0.038 | From - 180 to + 875 | Non-flammable |
| 150 | 0,055 | 0.054 ÷ 0.04 | |||
| 225 | 0,058 | 0.057 ÷ 0.042 | |||
| Thermal insulation products from expanded polystyrene | 30 | 0,033 | 0.032 ÷ 0.024 | From - 180 to + 70 | Combustible |
| 50 | 0,036 | 0.035 ÷ 0.026 | |||
| 100 | 0,041 | 0.04 ÷ 0.03 | |||
| Thermal insulation products made of polyurethane foam | 40 | 0,030 | 0.029 ÷ 0.024 | From - 180 to + 130 | Combustible |
| 50 | 0,032 | 0.031 ÷ 0.025 | |||
| 70 | 0,037 | 0.036 ÷ 0.027 | |||
| Thermal insulation products made of polyethylene foam | 50 | 0,035 | 0,033 | From - 70 to + 70 | Combustible |
But the inquisitive reader will surely ask: where is the answer to one of the main questions that arise - what should be the thickness of the insulation?
This question is quite complex, and there is no definite answer to it. If desired, you can use cumbersome calculation formulas, but they are probably understandable only to qualified heating engineers. However, not everything is so bad.
Manufacturers of finished thermal insulation products (shells, cylinders, etc.) usually lay down the required thickness, calculated for a specific region. And if mineral wool insulation is used, then you can use the data of the tables, which are given in a special Code of Rules, which was developed specifically for thermal insulation of pipelines and technological equipment. This document is easy to find on the web by entering a search query "SP 41-103-2000".
For example, here is a table from this reference book concerning the overground placement of the pipeline in the Central region of Russia, when using mats made of glass staple fiber grade M-35, 50:
| Outer diameter pipeline, mm | Heating pipe type | |||||
|---|---|---|---|---|---|---|
| innings | return | innings | return | innings | return | |
| Average temperature regime of the coolant, ° С | ||||||
| 65 | 50 | 90 | 50 | 110 | 50 | |
| Required insulation thickness, mm | ||||||
| 45 | 50 | 50 | 45 | 45 | 40 | 40 |
| 57 | 58 | 58 | 48 | 48 | 45 | 45 |
| 76 | 67 | 67 | 51 | 51 | 50 | 50 |
| 89 | 66 | 66 | 53 | 53 | 50 | 50 |
| 108 | 62 | 62 | 58 | 58 | 55 | 55 |
| 133 | 68 | 68 | 65 | 65 | 61 | 61 |
| 159 | 74 | 74 | 64 | 64 | 68 | 68 |
| 219 | 78 | 78 | 76 | 76 | 82 | 82 |
| 273 | 82 | 82 | 84 | 84 | 92 | 92 |
| 325 | 80 | 80 | 87 | 87 | 93 | 93 |
Similarly, you can find the required parameters for other materials. By the way, the same Code of Rules does not recommend significantly exceeding the specified thickness. Moreover, the maximum values \u200b\u200bof the insulation layer for pipelines have been determined:
| Outer diameter of the pipeline, mm | Maximum thickness of the thermal insulation layer, mm | |
|---|---|---|
| temperature 19 ° C and below | temperature 20 ° C and more | |
| 18 | 80 | 80 |
| 25 | 120 | 120 |
| 32 | 140 | 140 |
| 45 | 140 | 140 |
| 57 | 150 | 150 |
| 76 | 160 | 160 |
| 89 | 180 | 170 |
| 108 | 180 | 180 |
| 133 | 200 | 200 |
| 159 | 220 | 220 |
| 219 | 230 | 230 |
| 273 | 240 | 230 |
| 325 | 240 | 240 |
However, do not forget about one important nuance. The fact is that any insulation with a fibrous structure will inevitably shrink over time. And this means that after a certain period of time, its thickness may become insufficient for reliable thermal insulation of the heating main. There is only one way out - even during the installation of insulation, immediately take into account this correction for shrinkage.
For the calculation, you can apply the following formula:
Н \u003d ((D + h) : (D + 2 h)) × h× Kc
H- thickness of the layer of mineral wool, taking into account the correction for compaction.
D- the outer diameter of the pipe to be insulated;
h- the required thickness of insulation according to the table of the Code of Rules.
Ks- coefficient of shrinkage (compaction) of fibrous insulation. It is a calculated constant, the value of which can be taken from the table below:
| Thermal insulation materials and products | Compaction factor Kc. |
|---|---|
| Mineral wool stitched mats | 1.2 |
| Heat-insulating mats "TEKHMAT" | 1.35 ÷ 1.2 |
| Mats and webs made of super-thin basalt fiber when laid on pipelines and equipment with nominal bore, mm: | |
| Du | 3 |
| 1,5 | |
| DN ≥ 800 with an average density of 23 kg / m3 | 2 |
| ̶ the same, with an average density of 50-60 kg / m3 | 1,5 |
| Glass staple fiber mats on a synthetic binder grade: | |
| M-45, 35, 25 | 1.6 |
| M-15 | 2.6 |
| Glass staple fiber mats "URSA" brands: | |
| M-11: | |
| ̶ for pipes with DN up to 40 mm | 4,0 |
| ̶ for pipes with DN 50 mm and more | 3,6 |
| M-15, M-17 | 2.6 |
| M-25: | |
| ̶ for pipes with DN up to 100 mm | 1,8 |
| ̶ for pipes with DN 100 to 250 mm | 1,6 |
| ̶ for pipes with DN over 250 mm | 1,5 |
| Mineral wool slabs on a synthetic binder grade: | |
| 35, 50 | 1.5 |
| 75 | 1.2 |
| 100 | 1.10 |
| 125 | 1.05 |
| Glass staple fiber slabs grades: | |
| P-30 | 1.1 |
| P-15, P-17 and P-20 | 1.2 |
To help the interested reader, a special calculator is placed below, which already contains the indicated ratio. It is worth entering the requested parameters - and immediately get the required thickness of mineral wool insulation, taking into account the amendment.
Thermal insulation of pipelines is one of the important measures to ensure the durability of steel (VGP; ES; BSh) and polymer pipes.
Section materials
| → Cylinders Rockwool | → Expanded polystyrene shell |
| → K-FLEX | → PPU shell |
| → K-FLEX PE | → Basalt mats |
| → Cylinders FOAMPIPE | → ProRox PS 960 |
| → FOAMPIPE bends | → Covers for pipes with insulation |
| → Tees FOAMPIPE | → Aluminum tape |
| → Foampipe Sewer drainage insulation | → Band clamp |
| → Thermal insulation boxes Foampipe TK | → Fiberglass |
Thermal insulation of heating pipes is no less important than thermal insulation of a basement, walls or roof of a building. The main reason for this is the uninterrupted supply of water during the cold season, therefore it is simply necessary to insulate the water supply.
How is the correct thermal insulation of heating pipes going?
Depending on the material used, pipe insulation differs in structure and production technology.
Selection and installation of pipe insulation is a matter of only an experienced specialist. Otherwise, over time, it will be necessary to redo the work performed again.
To ensure a long period of operation of the pipeline, it is always necessary to take into account the climatic conditions in which the heating or water supply networks will be operated, and entrust the installation of the material only to professionals.
Thermal insulation of water supply pipes is the most important stage in the creation of water supply or sewerage systems. Correct thermal insulation of the pipes guarantees the normal functioning of the pipeline even in the cold season. Hurry and savings on insulation leads to the need for regular repairs.
Only high-quality materials should be chosen for thermal insulation of pipelines. It should also be borne in mind that it is important not only to protect the pipe from the effects of cold, but also to provide protection against corrosion by creating an anti-corrosion layer.
It should be remembered that the thermal insulation of pipes must have a long service life, so that there is no need for frequent replacement. Depending on the passage of the pipeline (external or underground), different types of pipe insulation are used.
For indoor applications, it is best to use ROCKWOOL insulating cylinders. Products from a well-known manufacturer have high quality and unique properties. High requirements for technical insulation products today allow Rockwool cylinders to be No. 1. They are made of mineral wool on a synthetic binder 1 meter long. They can be of various diameters from 19 to 273 mm. The thickness of hollow products can be 30, 40, 50, 60, 70 and 80 mm. Cylinders can be produced with an additional aluminum foil coating.
For outdoor use, Rockwool mineral wool cylinders can also be used, but with subsequent cover in the form of protective shells. They protect products from precipitation and damage to thermal insulation. It is also possible to use mineral wool mats Tech mat and Wired Mat.
Thermal insulation for pipes can be made with polyurethane foam shells or expanded polystyrene shells. For in-ground applications, this is the most common insulation option. In any case, it is recommended that all the necessary measures to protect pipes be carried out strictly according to the project, in which certain materials necessary for insulation are prescribed.
Thermal insulation of heating pipes is a reliable protection of pipes. The efficiency of heating mains depends on the heat-insulating material, because without it, heat loss occurs, especially in winter. All this is reflected in the wallets of our citizens.
Affordable prices for pipeline insulation
Today, you can buy thermal insulation for pipes at different prices. When choosing a particular material, the buyer is often interested in what the price of insulation for the pipeline depends on. The answer to the question is simple.
The material cost is influenced by the following:
- √ country of origin - imports are always more expensive compared to domestic goods, although they are the same in quality;
- √ the density of the material - the denser, the more expensive;
- √ insulation thickness;
- √ the ratio "pipeline insulation - price" depends entirely on the construction material;
- √ wholesale purchase is always cheaper than retail.
However, when buying thermal insulation for pipes, you should choose only the product that best suits the given, specific operating conditions. In this case, by paying once, the buyer will enjoy the smooth operation of the pipeline for a long time.
The overwhelming majority of regions of our country are characterized by very severe winters. Frosts in minus 20 degrees and below - you will not surprise anyone. And even in the southern regions, with a mild climate, the weather sometimes presents "surprises" when the thermometer drops below zero for quite a long time. That is, almost at any point in private construction, you have to think about how to protect it from freezing.
Frozen water in pipes is not only and even not so much a temporary loss of one of the communal "amenities". Most often, such troubles entail literally disastrous consequences - they end with a rupture of the pipe walls, a complete failure of the entire home system, the need for large-scale repair and restoration work. And to hope for some illusory luck, they say, this will not happen to me is extremely short-sighted. In any case, you cannot do without high-quality insulation of the system.
Let's see what kind of insulation can be used for water supply pipes, we will deal with the types of materials, with their advantages and disadvantages. And with the main question - what should be the thickness of this insulation layer.
What methods are used to protect water pipes from freezing
It does not matter whether a private house receives water distribution from a central collector (and this also often happens), or an autonomous source (a well or a well) will be used, it is still assumed that a pipe will be laid where negative external temperatures are likely. The only exception can be considered only those rare cases when the well is drilled directly in the basement of the house. And even then - on the way to the points of consumption, there may also be sections of the water supply through the unheated basement or basement. But in order to disable the water supply system, a very short non-insulated section is enough.
What approaches are practiced to protect water pipes from freezing?
- First of all, the water main, if possible, should be laid below the level of soil freezing in this region. At such a depth of the line (and it is taken with a margin - the level of freezing plus another 300 ÷ 500 mm), the temperature should never reach negative values. That is, the probability of getting an "ice plug" tends to zero.
However, this approach is not always fully feasible. In some regions, the soil freezes to a very significant depth, and digging such deep trenches significantly complicates the implementation of the project. Are not uncommon and such areas where the soil features and completely exclude such an arrangement of pipes.
In many regions, the level of soil freezing reaches very significant depths. It is not always possible to dig such deep trenches for laying water pipes. In addition, the pipe, one way or another, must be lifted up in order for it to enter the house. And it will in any case pass through the "dangerous" sections - the upper sections of the route, the passage through the foundation, through the basement, basement or even simply unheated room, where negative temperatures can be observed in winter.
How an autonomous water supply system is built in a private house
Much depends on the water source, on its location on the site, distance from the residential building, on the climatic conditions of the region and on the design features of the building itself. Read more about that in a special publication of our portal.
- Those same "problem areas" of the water pipeline route can be artificially heated using electrical energy. For these purposes, special heating cables are used, which are laid on the pipe walls under a layer of thermal insulation, or even placed directly in the pipe cavity.
There are many types of such cables on sale nowadays, as well as automatic heating control units, which I turn on the power when required.
How to arrange water supply heating?
The advent of heating cable systems has removed a lot of problems when organizing autonomous water intakes in private houses. By the way, if you strictly follow the instructions of the manufacturers of such products, then it is quite possible to mount and run it yourself. More details - in a special publication of our portal.
- In the basement, basement or other rooms of the house, in which a negative temperature level is not excluded, sometimes the laying of a "thermal satellite" is practiced. This is a pipe running parallel to the water supply and enclosed in a common thermal insulation shell, which is nothing more than one of the branches of the general heating circuit of the house.
Such a campaign, of course, complicates both the plumbing system and the heating system. But on the other hand, there is no need to worry about the integrity of areas with such heating. True, only when the heating is on.
- One of the radical ways to prevent water freezing in pipes is to maintain a constant high pressure in them. For this, the autonomous water supply system is supplemented with special equipment, and the pipes themselves must be able to withstand these increased loads.
The approach, although effective, is quite complex both in the organization and in everyday operation. In addition, it turns out to be more expensive in terms of energy consumption. Such systems have not gained much popularity.
- The most common method is thermal insulation of pipes, which is what, in fact, this publication is devoted to. The use of various heaters helps to avoid freezing of the water supply system, if, of course, the material and thickness of the insulation are selected correctly.
All this will be discussed in more detail below.
A special type of insulation is sometimes referred to as the creation of a fixed air gap between the water pipe and the casing, which prevents the pipe from direct contact with the ground. In a nutshell, this can be summed up as "pipe in pipe".
But, in truth, this method is not applied in its "pure form". The hollow space, if only in order to accurately position the water pipe inside the outer shell, is still filled with insulation material. Which, in principle, is a heater only because of its ability to create a layer of immobilized air. So the result is a classic pipe thermal insulation with the creation of an outer casing. And he, by the way, is always welcome, for protection and insulation, and the pipe itself from mechanical influences, from soil moisture, from damage that can be caused by rodents living underground, attracted by the heat in winter.
In practice, a combination of most of the listed methods of protecting water pipes from freezing is usually used. That is, they try to deepen the route from the well or well as much as possible, insure the most vulnerable areas with additional heating and, of course, provide for reliable thermal insulation, usually along the entire length of the water pipe.
Such an integrated approach is also necessary from the considerations that even high-quality insulation often does not guarantee the complete protection of the water supply system. The table below shows the heat loss values \u200b\u200bcalculated for pipes of different outside diameters, enclosed in a layer of thermal insulation of different thicknesses. The thermal conductivity coefficient of the insulation is taken as an average characteristic of most thermal insulation materials used in the considered role - 0.04 W / (m × K).
Naturally, the amount of heat loss depends directly on the difference in temperature between the environment and the liquid pumped through the pipe. Several options are given in the table - from Δt \u003d 20 ℃ to Δt \u003d 60 ℃. For example, if the temperature of water from a well (well) in winter is + 2 ÷ 4 ℃, and on a, the pipe passes through the basement of the house, frozen to -15 ℃, then the temperature difference can be considered 20 degrees.
| Insulation layer thickness | Temperature difference (Δt, ° С) | Pipeline outer diameter (mm) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 150 | ||
| Average heat loss rate (W for each running meter of the pipeline) | |||||||||||
| 10 mm | 20 | 7.2 | 8.4 | 10 | 12 | 13.4 | 16.2 | 19 | 23 | 29 | 41 |
| 30 | 10.7 | 12.6 | 15 | 18 | 20.2 | 24.4 | 29 | 34 | 43 | 61 | |
| 40 | 14.3 | 16.8 | 20 | 24 | 26.8 | 32.5 | 38 | 45 | 57 | 81 | |
| 60 | 21.5 | 25.2 | 30 | 36 | 40.2 | 48.7 | 58 | 68 | 86 | 122 | |
| 20 mm | 20 | 4.6 | 5.3 | 6.1 | 7.2 | 7.9 | 9.4 | 11 | 13 | 16 | 22 |
| 30 | 6.8 | 7.9 | 9.1 | 10.8 | 11.9 | 14.2 | 16 | 19 | 24 | 33 | |
| 40 | 9.1 | 10.6 | 12.2 | 14.4 | 15.8 | 18.8 | 22 | 25 | 32 | 44 | |
| 60 | 13.6 | 15.7 | 18.2 | 21.6 | 23.9 | 28.2 | 33 | 38 | 48 | 67 | |
| 30 mm | 20 | 3.6 | 4.1 | 4.7 | 5.5 | 6 | 7 | 8 | 9 | 11 | 16 |
| 30 | 5.4 | 6.1 | 7.1 | 8.2 | 9 | 10.6 | 12 | 14 | 17 | 24 | |
| 40 | 7.3 | 8.3 | 9.5 | 10.9 | 12 | 14 | 16 | 19 | 23 | 31 | |
| 60 | 10.9 | 12.4 | 14.2 | 16.4 | 18 | 21 | 24 | 28 | 34 | 47 | |
| 40 mm | 20 | 3.1 | 3.5 | 4 | 4.6 | 4.9 | 5.8 | 7 | 8 | 9 | 12 |
| 30 | 4.7 | 5.3 | 6 | 6.8 | 7.4 | 8.6 | 10 | 11 | 14 | 19 | |
| 40 | 6.2 | 7.1 | 7.9 | 9.1 | 10 | 11.5 | 13 | 15 | 18 | 25 | |
| 60 | 9.4 | 10.6 | 12 | 13.7 | 14.9 | 17.3 | 20 | 22 | 27 | 37 | |
As you can see, even with a rather thick insulation layer of 40 mm, a pipe with a diameter of 32 mm in the conditions taken above for example will lose almost 5 watts of thermal energy for each running meter. It seems to be a little, but if there is no water movement in the pipe for several hours, an ice plug may appear in such an area. This means that these heat losses will have to be replenished in one way or another.
That is, when designing your water supply system, you must carefully analyze theoretically vulnerable areas, and strengthen thermal insulation on them (if possible) or take steps to heat these "dangerous" areas. Which, by the way, are usually just located in the immediate vicinity of the house or even directly in it. Although, it also happens that the entire route from the source to the house has to be heated, since, for example, rocky soil or a high location of groundwater make it impossible to dig trenches below the freezing level.
But even in this case, the importance of pipe insulation only increases. The heat generated by the heating system should not dissipate in vain, but fulfill its intended purpose. And this cannot be achieved without high-quality thermal insulation.
Requirements for thermal insulation for water pipes
So, I will go directly to thermal insulation for water pipes. And first of all - let's figure out what requirements it should ideally meet.
From the above, it should already be clear that thermal insulation of pipes is designed to perform two key interrelated tasks:
Protection of the water supply system from the temperature falling below the zero mark in it - in order to avoid freezing of water, entailing a loss of system performance and pipe rupture.
In areas with forced heating - minimization of heat losses for efficient and economical operation of the heating cable.
High-quality insulation must meet the saddle criteria:
- The first place, of course, should be given to its thermal insulation qualities. The lower the thermal conductivity, the more efficiently heat is retained, the thinner the thermal insulation layer can be provided.
- The water supply in an autonomous system is mainly located in the ground, that is, in a humid soil environment. This means that thermal insulation must be resistant to moisture, best of all, hydrophobic. A wet insulation always loses dramatically in its thermal insulation qualities. Those sections of pipelines that pass in the open air also need protection from moisture.
Not all materials meet this criterion equally. But this is partly solved by enclosing the insulated pipes in a waterproof shell or casing.
- The soil is very often saturated with very aggressive chemical compounds. This means that both the insulation itself and the layer that protects it must be inert to such an effect.
- An important criterion is the mechanical strength of the material. The insulation layer in the ground will experience serious ground pressure. In open areas, external mechanical influences cannot be excluded.
- The laying of a water supply system, especially in buried areas, is done with the expectation of long-term operation. This indicates the need for a pronounced durability of the insulation material.
- Good modern thermal insulation should not be difficult to install. Very often, when creating a water supply system, ready-made solutions are used - already insulated pipes, which can only be mounted into a common highway, and then insulate the joints.
- Of course, the availability of material is always an important criterion - both in terms of supply to stores and in terms of cost. But here it should be noted right away that high-quality modern pre-insulated pipes a priori cannot be cheap.
Now let's see what materials are used to insulate water pipes.
Thermal insulation materials for water pipes.
Mineral wool of various types, expanded polystyrene, polyurethane foam, and polyethylene foam are widely used to insulate water pipes. Recently, a relatively new insulation - foamed rubber - has been increasingly used.
Mineral wool
This is perhaps the most affordable thermal insulation material for such purposes. But it is far from the most convenient.
Of the three existing types of mineral wool, only two are actually used for pipeline insulation - glass wool and stone (basalt). The so-called slag wool made from metallurgical waste is poorly suited for such purposes. She loses in thermal insulation qualities, is quickly saturated with water, far from everything is in order with her and with the chemical composition, which under certain conditions can become a catalyst for active corrosion of metal pipes.
What are dignity mineral wool insulation:
- Low coefficient of thermal conductivity.
- One of the important advantages over many other heaters is plasticity. Mineral wool can be used to insulate curved or flat surfaces, tees, bends, valves and other fittings without any problems and without the need to purchase additional products.
- Chemical inert to most acidic or alkaline compounds that can be found in soil moisture.
- A variety of release forms, any of which, in principle, can be used for pipe insulation. So, mineral wool is also produced in mats, including stitched ones, in separate slabs (blocks) of various thicknesses. This allows, by the way, to independently vary the thickness of the created insulation layer, depending on the initial conditions.
Made from mineral wool and special products for thermal insulation of pipes - half-cylinders ("shell" in common parlance) of various internal and external diameters, with or without external coating. It is very convenient for quick installation on straight sections of the water supply system.
- Mineral wool is practically non-combustible material. For underground sections of the water supply system, this quality may not be so important, but for open ones it will be useful.
Now let's go through disadvantages of this material:
- First of all, it should be noted that many types of mineral wool are hygroscopic. To a greater extent, this applies to fiberglass materials. They can quite actively absorb moisture, losing their insulation characteristics. And when wet mineral wool freezes, its destructuring, strong shrinkage occurs.
Basalt types of mineral wool usually undergo a special hydrophobic treatment and are more resistant to contact with water.
But in any case, such a heater must necessarily be protected from direct contact with wet soil. This is achieved by creating a surface protective layer of aluminum foil, roofing felt or even just a dense plastic film. The task is not particularly difficult: such an outer covering is simply wound from above with a certain overlap (overlap) of the turns, and then fixed with wire or other clamps. But at the same time - such additional operations complicate the installation of thermal insulation.
As we saw above, some types of mineral wool pipe insulation are already equipped with an applied outer coating. This greatly simplifies thermal insulation work, but such materials are also more expensive.
- Working with mineral wool requires certain precautions and the use of skin, eye, and respiratory protection equipment. Fibers are brittle (again, glass wool suffers more from this, basalt fibers have much better elasticity), and sharp microscopic debris often cause serious irritation of the skin and mucous membranes.
- Another disadvantage is the tendency of mineral wool to gradually cake, lose in volume (in the thickness of the insulation layer). The reason for this is the same fragility of fibers, which can increase under unfavorable conditions (waterlogging + negative temperatures) or under vibration.
The shrinkage of mineral wool insulation should be taken into account when planning the thermal insulation of pipes. How this is taken into account will be described below.
Heaters from expanded polystyrene (PPR)
Expanded polystyrene (or, as it is often called, polystyrene) is very widely used precisely for the purpose of thermal insulation of various parts of the building. Plumbing is no exception.
By the way, this material is rightly criticized for a number of very negative qualities that limit its use in residential premises. First of all, these include unfavorable conditions from an environmental point of view, flammability and extremely toxic combustion products. But in terms of using for thermal insulation of underground sections of the water supply, these qualities are completely unimportant. So the use of PPR should not cause any special alarms.
The advantages of expanded polystyrene include:
- Excellent thermal insulation performance.
- Low density - the material is lightweight, very easy to process and install.
- A high-quality PPR is not afraid of moisture - it practically does not penetrate into its structure.
- The cost of PPR products is low - the cost of insulation will be small.
- The material is durable if it is protected from external mechanical damage and from contact with organic solvents.
It is most convenient, of course, to use "shells" for pipe insulation - half-cylinders with the required inner and outer diameter. High-quality products of this type are also equipped with a groove-ridge lock, which prevents the appearance of cold bridges at the border of the two halves.
Such half-cylinders are put on from both sides on the pipe, connected in locks, and then tied with tape or even just wire clamps. On straight sections of the water supply route, thermal insulation does not take much time.
Disadvantages , in addition to those already listed above, the following can be considered:
- The material is quite fragile, and the "shell" is easy to break if handled carelessly.
- The complete absence of any plasticity. That is, even at a slight bend in the route, you will have to isolate this section separately, and then again switch to half-cylinders.
True, many companies engaged in the production of such "shells" offer in their assortment also special shaped parts for bends, tees and some other units. But, traditionally, the cost of such accessories is much higher than the price of "linear" elements. Therefore, many experienced craftsmen try to cut out the required parts for elbows, tees, etc. from the half-cylinders on their own. Or, these areas are insulated with mineral wool and then covered with a waterproof casing.
They are used for insulating water pipes and expanded polystyrene plates. For example, they are laid on top of the pipe before backfilling the trench - a kind of screen is obtained that prevents vertical penetration of cold into the depths.
Another option is that a box is built from expanded polystyrene plates at the bottom of the trench, into which pipes are laid. After installing the water supply, the box is closed with a lid from the same plate, and then the soil is backfilled.
With the affordable cost of white foam plates, this insulation option will be perhaps the least expensive.
- Expanded polystyrene cannot be classified as chemically resistant polymers. Even ordinary fuels and lubricants are capable of causing its destructuring.
Therefore, such insulation should be used with caution if the soil is saturated with petroleum products (which often happens, for example, near a parking lot). Or, which would be more correct, provide for external protection for the "shell", for example, from a dense plastic film.
Polyurethane foam insulation for pipes
With a certain external similarity with expanded polystyrene (more precisely, with its extruded variety), polyurethane foam significantly surpasses it in almost all respects.
As a rule, in "pure form" polyurethane foam heaters for pipes are not produced. But manufacturers offer a wide range of pre-insulated pipes. On such products, ready for laying, the pipe is already protected by a layer of high-quality polyurethane foam insulation and an outer coating that is resistant to mechanical stress, moisture, and chemical attack. By the way, polyurethane foam itself is much more resistant to various aggressive compounds. Moreover, sprayed onto the outer walls of the pipe, it also becomes their excellent anti-corrosion protection.
Consumers are offered a wide range of metal pipes in finished polyurethane foam insulation. But their diameter usually starts from 57 mm and more. As a rule, when installing an autonomous water supply system, it is necessary to use not so large pipes.
Therefore, some well-known companies have launched the production of small-diameter plastic or metal-plastic pipes, which also have polyurethane foam-thermal insulation and an external polymer coating. Such ready-made solutions greatly simplify the entire process of installing a water supply system, laid both in the ground and in open areas - in basements, basements, unheated rooms.
On both sides of these pipes, a small "bare" area protrudes from the thermal insulation, which is sufficient for a weld or fitting connection. After that, a heat-shrinkable sleeve, previously put on the pipe, is pushed onto this joint. It remains to fill the cavity of the coupling with polyurethane foam (which itself is also polyurethane foam), so that after the foam hardens, a perfectly insulated sealed joint is obtained.
As you can see in the figure above, customers are also offered ready-made parts for the installation of individual sections of the water supply system - bends with different angles of rotation, tees, transitions, etc. That is, the installation of the system turns into a kind of "constructor assembly".
By the way, despite the fact that polyurethane foam cannot be called too plastic material, some polymer pipes in such thermal insulation with an external coating still have a certain flexibility, which allows laying curved sections without using additional bends.
An example of this is the products of the Russian company Polymerteplo Group, Izoproflex pipes. The pipe itself is made of PEX-A cross-linked polyethylene, reinforced with high-strength fiber, has a protective anti-diffusion layer, a semi-rigid polyurethane foam insulation, and an external protective coating made of durable polyethylene.
Such pipes are sold in coils, which in itself speaks of their flexibility. The installation task becomes even easier - if there are no sharp turns, then one sleeve, already pre-insulated and protected from the outside, can be laid from the water intake to the very entrance to the house, without making a single extra joint.
Polyethylene foam insulation
Another material widely used for pipeline insulation. In its closed cellular structure, filled with air, it is very similar to polyurethane foam. Quite glare and their thermal conductivity values \u200b\u200b- both are excellent thermal insulators. But unlike polyurethane foam, foamed polyethylene also has high flexibility and plasticity. Not to the detriment of strength properties.
The material is very light - usually its density does not exceed 30 ÷ 35 kg / m³, that is, no special physical efforts will have to be applied when installing thermal insulation. The closed cellular structure becomes an insurmountable barrier to water, the material itself practically does not absorb moisture - no more than 1.5% of the volume, even when fully immersed.
Chemical inertness is also a clear advantage - it is difficult to imagine which of the compounds that got into the soil could cause the destructuring of polyethylene foam. The operating temperature range is also impressive - from minus 55 to plus 85 ℃, which is more than enough for a water supply system.
Various forms of such insulation are produced. These can be just rolls, as a rule, with one foil side - many craftsmen prefer just such a material. But still, ready-made sleeves for pipes of different diameters and with different thicknesses of the insulation layer, usually 2 meters long, are currently more popular.
Installation of such sleeves is not difficult - they have a seam along the entire length on their side, along which they can be opened. The insulation is put on the pipe, and then this seam is glued together almost without a trace due to the applied self-adhesive layer.
But, again, the most convenient solution is to use ready-made plastic pipes, already “dressed” in insulation and in an outer protective shell. Such products in a wide range are offered by several leading manufacturers.
For example, FLEXALEN offers products with a polybutene pressure pipe, with a multi-layer insulation made of polyethylene foam and an outer protective casing made of polyethylene of low pressure (HDPE).
Traditionally, the products of the Uponor companies are in high demand (the old name - Ecoflex can be found) and Watts- Microflex "... The pressure head of the pipes is made of cross-linked polyethylene, the insulation is several layers of foamed polyethylene, and the outer shell is HDPE.
Please note that in the model range of all these companies there are samples with two or more pressure pipes in a common layer of thermal insulation and a protective casing. This can also be very convenient if, for example, water is directed to two different places, or in heating systems - for supply and return pipes, or for the heat satellite already mentioned above.
Find out how to insulate a water supply using a heating cable from our new article -
Completing the review of insulation materials, it should also be mentioned thermal insulation made of foamed rubber. In terms of the coefficient of thermal conductivity, this material outperforms polyethylene foam and practically competes on an equal footing with polyurethane foam. And at the same time it is distinguished by excellent plasticity and all other properties necessary for a high-quality insulation material.
The traditional form of release for such a heater is similar - in the form of insulating sleeves (cylinders). And how the insulation is carried out, including complex sections of the water supply system, is well shown in the video below:
Video: Thermal insulation of water pipes with Kaiflex foam rubber sleeves
To complete the review of materials would be a logical comparison table with the main parameters of the insulation materials mentioned above.
Comparative table of key parameters of popular pipe heaters
| Material, product | Average density in the composition of the insulation structure, kg / m3 | Thermal conductivity of insulation (W / (m × K)) for surfaces with temperature (° C) | Operating temperature range, ° С | Flammability group | |
|---|---|---|---|---|---|
| 20 and up | 19 and below | ||||
| Broached mineral wool plates | 120 | 0.045 | 0,044-0,035 | -180 to +450 for mats, fabric, mesh, fiberglass canvas; up to 700 - on a metal mesh | Non-flammable |
| 150 | 0.049 | 0,048-0,037 | |||
| Thermal insulation boards made of mineral wool on a synthetic binder | 65 | 0.04 | 0,039-0,03 | -60 to +400 | Non-flammable |
| 95 | 0.043 | 0,042-0,031 | |||
| Mineral wool semi-cylinders and cylinders | 50 | 0,04 | 0,039-0,029 | -180 to +400 | Non-flammable |
| 80 | 0,044 | 0,043-0,032 | |||
| 100 | 0,049 | 0,048-0,036 | |||
| 150 | 0,05 | 0,049-0,035 | |||
| 200 | 0,053 | 0,052-0,038 | |||
| Glass staple fiber mats on synthetic binder | 50 | 0,04 | 0,039-0,029 | -60 to +180 | Non-flammable |
| 70 | 0,042 | 0,041-0,03 | |||
| Superfine glass fiber mats and wadding without binder | 70 | 0,033 | 0,032-0,024 | -180 to +400 | Non-flammable |
| Mats and wadding made of super-thin basalt fiber without binder | 80 | 0,032 | 0,031-0,24 | -180 to +600 | Non-flammable |
| Thermal insulation products from expanded polystyrene | 30 | 0,033 | 0,032-0,024 | -180 to +70 | Combustible |
| 50 | 0,036 | 0,035-0,026 | |||
| 100 | 0,041 | 0,04-0,03 | |||
| Thermal insulation products made of polyurethane foam | 40 | 0,030 | 0,029-0,024 | -180 to +130 | Combustible |
| 50 | 0,032 | 0,031-0,025 | |||
| 70 | 0,037 | 0,036-0,027 | |||
| Thermal insulation products made of polyethylene foam | 50 | 0,035 | 0.033 | -70 to +70 | Combustible |
| Thermal insulation products from foamed ethylene-polypropylene rubber "Aeroflex" | 60 | 0,034 | 0.033 | -57 to +125 | Low-flammable |
What thickness of insulation is needed?
Surely the interested reader will have a question - what should be the thickness of the insulation layer in order to ensure that the water pipe is protected from freezing.
The answer to this is not easy. There is a calculation algorithm that takes into account the mass of the initial values, and includes several formulas that are difficult even for visual perception. This technique is set out in the Code of Rules SP 41-103-2000. If anyone wants to find this document and try to carry out an independent calculation - you are welcome.
But there is an easier way. The fact is that the specialists have already taken upon themselves the brunt of the calculations - in the same document (SP 41-103-2000), which is easy to find by any search engine, the appendix contains many tables with ready-made values \u200b\u200bof the insulation thickness. The only problem is that it is physically impossible to present these tables here in our publication. They are compiled for each type of insulation separately, and - with a gradation also according to the place of placement - ground, open air or room. In addition, the type of pipeline and the temperature of the pumped liquid are taken into account.
But if you spend 10-15 minutes to study the tables, then there will certainly be an option in them that is as close as possible to the conditions that interest the reader.
It would seem that this is all, but it is required to dwell on one more important nuance. It applies only to cases of water pipe insulation with mineral wool.
When it came to this thermal insulation material, in a series of shortcomings of mineral wool, its tendency to gradual caking and shrinkage was indicated. This means that if you initially set only the estimated thickness of the insulation, then after some time the thickness of the insulation layer may become insufficient for full thermal insulation of the pipe.
Therefore, when performing insulation, it is advisable to pre-lay a certain margin of thickness. The question is what?
This is easy to calculate. There is a formula that, I think, there is no point in demonstrating here, since this online calculator is based on it.
Two initial values \u200b\u200bfor the calculation are the outer diameter of the insulated pipe and the recommended value of the thermal insulation thickness found from the tables.
One more parameter remains unclear - the so-called "compaction coefficient". We take it from the table below, focusing on the selected thermal insulation material and the diameter of the pipe to be insulated.
| Mineral wool insulation, diameter of the insulated pipe | Compaction factor Kc. |
|---|---|
| Mineral wool stitched mats | 1.2 |
| Thermal insulating mats "TEKHMAT" | 1.35 ÷ 1.2 |
| Mats and cloths made of super-thin basalt fiber (depending on the nominal pipe diameter, mm): | |
| → Du | 3 |
| 1,5 | |
| → DN ≥ 800, with an average density of 23 kg / m³ | 2 |
| ̶ the same, with an average density of 50-60 kg / m³ | 1,5 |
| Glass staple fiber mats on a synthetic binder, grade: | |
| → M-45, 35, 25 | 1.6 |
| → M-15 | 2.6 |
| URSA glass spatula fiber mats, brand: | |
| → M-11: | |
| ̶ for pipes with DN up to 40 mm | 4,0 |
| ̶ for pipes with DN 50 mm and more | 3,6 |
| → M-15, M-17 | 2.6 |
| → M-25: | |
| ̶ for pipes with DN up to 100 mm | 1,8 |
| ̶ for pipes with DN 100 to 250 mm | 1,6 |
| ̶ for pipes with DN over 250 mm | 1,5 |
| Mineral wool slabs on a synthetic binder grade: | |
| → 35, 50 | 1.5 |
| → 75 | 1.2 |
| → 100 | 1.1 |
| → 125 | 1.05 |
| Glass staple fiber slabs grades: | |
| → P-30 | 1.1 |
| → P-15, P-17 and P-20 | 1.2 |
Now, armed with all the initial values, you can use the calculator.
Insulation for pipes is a material that guarantees efficient operation of the system, maintaining a comfortable temperature in the house and uninterrupted circulation of the contents of the pipeline. In the conditions of our latitudes, all communications have to be insulated. The choice of thermal insulation is a demanding task, which is not easy to cope with, given the wide range. A small excursion on possible options - in this review from the editorial staff of HouseChief.
Good thermal insulation of the pipeline is a prerequisite for its successful operation
PHOTO: kimberia.ru
Read in the article
Thermal insulation: an urgent need or reinsurance
The soil freezes in almost all of our latitudes. If a pipeline with liquid contents ends up in frozen ground, it is likely to burst. In addition, direct contact with cold soil or air leads to significant heat loss. Part of the thermal energy will be wasted for heating the environment and will not reach the destination.
In houses, the boiler room is often located outside the main room, and the coolant has to travel a certain distance before getting into the radiators. The highway route can be through an attic, basement or unheated corridor.
The loss of part of the energy leads to unreasonable costs and excessive wear and tear of equipment PHOTO: torufix.ee
The sewage system is also very temperature dependent. Even if the pipeline is laid according to all the rules, with the necessary slope, a deposit forms inside the pipes, which, when frozen, can clog the system and lead to pipe rupture. Not only centralized systems are subject to such problems, but also autonomous structures with a septic tank.
There is always water in the water pipes. It begins to circulate when the tap is opened, and the rest of the time it can turn into ice in the freezing soil.
So there is no question of reinsurance. Thermal insulation is a really necessary procedure that should not be neglected if you do not want to constantly deal with repairs of engineering networks
PHOTO: vodakanazer.ru
Requirements for heat insulators for pipelines
In order for the insulation to effectively perform its task, it must meet several important requirements:
- the level of thermal conductivity should be as low as possible in order to effectively maintain the temperature of the contents of the line during the cold and warm seasons;
- thermal insulation must be safe for humans;
- the material must not be fire hazardous and must not support combustion;
- the insulation should not accumulate moisture, since this process reduces its ability to retain heat;
- installation of the material should be simple, with a minimum number of joints and the ability to isolate units of complex configuration;
- the maintainability of the insulation and the possibility of its repeated use are important;
- the material must be resistant to external influences, mechanical, atmospheric and chemical, as well as to a sharp drop in temperature.
Does material cost matter? As a rule, good insulation cannot be too cheap, although these materials usually do not require large expenses. PHOTO: aiss33.ru
What kind of insulation are suitable for these requirements? There are several options that are great for insulating pipes: mineral wool materials, foam heat insulators, and some bulk and liquid substances that can perform similar tasks.
Types of pipe heaters and their features
Consider the main options for heat insulators that are most effective for insulating sewage, heating and water supply systems.
Mineral wool materials
Fiberglass or stone wool is excellent at keeping you warm. If we compare these two types of insulation, then stone wool wins in terms of insulating properties. It can withstand temperatures up to 700 ° C and perfectly holds its shape even under mechanical stress. This insulation is resistant to aggressive chemicals and is relatively inexpensive.
But it also has its own unpleasant features. The main one is the ability to absorb moisture. With this process, stone wool gradually loses its thermal insulation properties. Therefore, if you opt for this material, you should consider another outer layer of waterproofing to protect against water.
This insulation is sold in plates, cylinders and rolls. The material can already be protected on one side with foil PHOTO: ecotherm.bg
Insulation expanded polystyrene
Foam insulation contains more than 50% air in its mass, which makes it one of the best. Its only drawback is its fragility, which does not allow it to bend to the shape of the pipe. But manufacturers solved this problem by releasing a foam shell, which is in the shape of a half-cylinder and can be worn on a pipe like a shirt.
The connection of the half-cylinders is carried out in a tongue-and-groove manner, which excludes the formation of cold bridges PHOTO: build-experts.ru
Such a shell can withstand temperature drops from -110 ° C to + 80 ° C. If your heating pipes reach a higher temperature, then a cork membrane should be laid between them and the foam.
Such insulation does not support combustion and can be used more than once.
A more perfect version of the shell is penoplex, which, with a smaller thickness, has better thermal insulation properties. Penoplex is more elastic, so it can bend a little if necessary.
Liquid penoizol
This material is applied by spraying and is used more often for pipe insulation in industrial premises. After such treatment, the pipe is completely hidden under the insulator layer, without the formation of cold bridges. In this way, it is convenient to insulate pipes with a complex configuration. Spraying services are not cheap. In a private household, an analogue of such insulation can be ordinary polyurethane foam.
So you can insulate a small piece of pipe.
PHOTO: prorab.help
Foamed polyethylene
Polyethylene is a fairly durable material that withstands mechanical stress well. This type of insulation is not afraid of moisture and protects metal pipes from corrosion damage. Operating temperature range - from -60 ° C to + 90 ° C. Foamed polyethylene resists fire for a long time, but if it burns, it does not emit toxins.
It is easy to install such insulation, it is elastic and suitable for pipes of any diameter. PHOTO: polifasplus.ru
The price of foamed polyethylene is an order of magnitude lower, for example, polyurethane. Thermal insulation for pipes made of this material is produced in the form of hollow cylinders up to 200 cm long and wall thickness up to 20 mm.
To put such a cylinder on a pipe, it is cut lengthwise, and then the place of the cut is fastened with tape. Roll material is simply wrapped around the pipes.
Foil penofol
Foil insulation is a modern and popular type of thermal insulation, easy to install and efficient in operation. Foil penofol can also be used to insulate pipes. It is produced in rolls and hollow cylinders.
Installation of penofol is similar to foamed polyethylene PHOTO: vystroim.com
Energoflex
This type of insulation is flexible. In fact, Energoflex is a type of high-pressure polyethylene foam. This material can be used outdoors. It is not afraid of water and can withstand temperatures from -60 ° C to + 90 ° C.
LDPE is resistant to aggressive chemicals and can be used for at least 25 years PHOTO: 7.allegroimg.com
Available in rolls and hollow cylinders.
The disadvantage of Energoflex is considered to be its susceptibility to direct ultraviolet light.
Heat insulating dyes
This is a relatively new type of thermal insulation, which is applied with a regular brush or roller. The thickness of the resulting layer is minimal, and the thermal insulation effect is quite high. The price of such paints "bites", and the secret of their manufacture is kept vigilantly by the manufacturers. It is only known that the heat-insulating effect is present due to the presence of microspheres with air in the paint composition. This coating can replace a five-centimeter layer of mineral wool.
In parallel, the dye protects pipes from corrosion and prevents condensation from forming on their surface PHOTO: gidpokraske.ru
Loose heaters
In addition to the listed materials, pipes in the ground are traditionally insulated with expanded clay. A layer of this material is able to retain heat with high quality and for a long time. To prevent the insulation from mixing with the ground, it is placed together with pipes in a box made of boards or in concrete shells.
Thermal insulation for pipes: how to make a choice
The choice of insulation depends on three main factors: the location of the pipeline, installation features and cost. In principle, any of the heaters listed above is easy to install with your own hands.
To keep pipes from overheating outside, foil insulation is used. According to the cost of the material, the most expensive will be mineral wool, and the cheapest - foamed polyethylene.
In the case when it is impossible to wrap the pipes with a heat insulator due to their complex structure or location, it is logical to use thermal paint.
For heating system
Heat insulating materials should be used for the heating system, which can be used in contact with high-temperature objects. These include mineral wool, foam and polyurethane foam.
For the insulation of a water supply system, two conditions are important: maximum heat retention and protection against corrosion. Polyurethane foam, which is applied in a liquid state, and heat-insulating paint are most suitable for this. Both of these options eliminate the formation of condensation and protect the pipes from rust.
For sewerage
Sewer pipes with an insufficient slope or passing less than half a meter from the ground surface must be insulated. This will require materials that do not absorb moisture and are resistant to mechanical stress.
Foamed polyethylene and penoizol are perfect for such purposes. PHOTO: tehnopena.ru
How to install insulation on pipes yourself
Installation of thermal insulation on pipes is a fairly simple task that even a beginner can solve. Here is a short video on this topic that will help you quickly understand the process:
Some nuances of installation in special conditions
To obtain effective insulation of pipe lines, you should follow a few simple recommendations:
- when insulating in unheated rooms, it is important to exclude cold bridges;
- in humid rooms, vapor barrier should be used over thermal insulation;
- insulation with a self-adhesive layer will greatly facilitate installation work;
- to eliminate minor flaws in the installation, use additional winding and reinforcing tape;
- carefully select rigid insulation - they must exactly match the diameter of the pipes.
If everything is done correctly, you will forget about problems with the work of communications PHOTO: bt-wpstatic.freetls.fastly.net
How did you insulate the pipes in your house? Write about it in the comments!