INSULATION OF HEAT NETWORKS

Currently, mineral wool, polyurethane foam (PPU), polyethylene foam and other foamed polymer thermal insulation materials and piece products made from lightweight concrete are most often used to insulate heating networks. Mineral wool insulation has low thermal conductivity in a dry state. But due to violations of transportation conditions, storage on a construction site, installation in conditions of high humidity, inaccurate fastening, damage to the vapor barrier film, mineral wool loses its heat-shielding properties, deforms, settles, which leads to the need for repair and replacement of the heat-insulating material. In addition, none of the mineral wools, including basalt wool, are suitable for insulating pipes with a coolant temperature above 250°C, since the impregnating composition decomposes. The polyurethane foam insulation used is mainly suitable for coolant temperatures up to 150°C. If the waterproofing is damaged and water gets in, the polyurethane foam decomposes. Piece thermal insulation materials capable of providing reliable thermal protection pipelines long time and having the necessary heat resistance, are made in the form of shells from perlite concrete, foam glass and other inorganic materials, have a fairly high cost and require manufacturing in a factory. Cheaper thermal insulation materials include non-autoclaved monolithic foam concrete of natural hardening - a type of lightweight cellular concrete obtained by hardening a solution consisting of cement, water and a surfactant, or simply foam. The foam ensures the necessary air content in the solution and its uniform distribution throughout the entire mass in the form of small closed cells, which gives the material thermal insulation properties and moisture resistance. Foam concrete has high adhesion to metal and reliably protects metal from external corrosion. The linear expansion coefficient of foam concrete is comparable to the linear expansion coefficient of a steel pipe. Foam concrete can be used for thermal insulation of pipelines, equipment, gas ducts and air ducts located both in buildings and outdoors in non-passable channels and for ductless installation with a coolant temperature from minus 150°C to plus 600°C, including pipelines of heating networks for new construction and repair work.

If the waterproofing is damaged, foam concrete can pick up up to 22-25% of water, which subsequently evaporates. At the same time, foam concrete, due to the hydration reaction, becomes stronger and retains its heat-shielding properties.

The technology of monolithic non-autoclaved foam concrete involves the use of mobile complexes that allow the production of thermal insulating foam concrete directly on site medium density 150 - 200 kg/m3 with pouring it into the annulus with subsequent hardening in natural conditions and the formation of a durable, heat-resistant heat-insulating layer on the surface of the pipeline. The installation for the production of foam concrete consists of: a low-speed, non-breaking foam mixer, a cyclic mixer, a foam generator for foam production, a compressor and a gerotor pump, which ensures a smooth supply of foam concrete with minimal destruction of air bubbles.

Work can be done in winter period at negative temperatures up to -15°C. In this case, it is necessary to ensure a positive temperature of the foam concrete during the first 4-5 hours. This is achieved by using when kneading hot water and insulation of the pouring area.

The cost of insulating pipes with monolithic foam concrete is significantly less than insulating with mineral wool or polyurethane foam.

Work production technology

Pipeline sections are cleaned of rust, dust, dirt, oil stains and insulation residues during repair work (Fig. 1).

Rice. 1 Pipeline section

The calculated thickness of the foam concrete layer is created using centralizers (Fig. 2) made of polymer materials (at a coolant temperature not exceeding 120°C) or galvanized steel, installed on insulated pipes at the rate of 1 centralizer per 1 casing (shell).

Rice. 2 Centralizer

Centralizers-plugs are installed at the initial and final sections of the pipeline (Fig. 3). In addition, plugs are installed along the length of the pipeline so that the volume of the limited area corresponds to the volume of the mixer.

Rice. 3 Centralizer-plug

Using self-tapping screws, a casing (shell) made of galvanized steel or aluminum is installed on the centralizers so that the filling hole is located at the top, strictly in the center of the pipe (Fig. 4). The filling holes are subsequently sealed with a waterproofing but vapor-permeable material in order to remove excess moisture from the foam concrete.

Rice. 4 Metal casing (shell) with filling holes.

Foam concrete is poured in 2 stages. Initially, a small volume of the area limited by the plugs is filled to control the possible leakage of the foam concrete mixture at the joints of the casing with fixed supports. Leakage areas are sealed polyurethane foam. Control of the filling of the space between the pipeline and the metal casing (shell) is carried out visually through the filling holes. The vertical sections of the pipeline are filled in the same way (Fig. 5).

Rice. 5 Vertical section prepared for pouring foam concrete.

Filling on an existing pipeline must be done at a coolant temperature of no more than 60°C. If the temperature is above 60°C, it is necessary to reduce the temperature to that specified for the curing time of the foam concrete (12-24 hours).

The thickness of the foam concrete layer depends on the temperature of the coolant, the temperature zone (for external pipelines) and the diameter of the insulated pipeline. Considering that the unit of measurement for pipeline insulation in standards and prices is accepted as 1 m3 of insulation, and in calculations they often operate on the diameter of the pipeline and its length, below is a table of the ratios of 1 m3 of insulation with the length of the insulated pipeline. The table is designed for insulating external pipelines in temperature zone III with foam concrete with a density of 200 kg/m3 at 4 coolant temperatures.

Diameter of the insulated pipeline, mm	Length of pipeline (m linear), insulated 1 m3 monolithic foam concrete grade D 200 at coolant temperature:

Journal “Pricing and estimate regulation in construction”, November 2009 No. 11

When carrying out work on equipment and installation of pipelines, it is necessary to comply with SNiP standards. What is SNiP? These are building codes and rules for organizing construction production, in accordance with standards, technical specifications and regulatory departmental acts.

Basic norms and rules for thermal insulation

Heating network- this is one of the main elements district heating. You should strictly adhere to the rules and regulations when drawing up a pipeline thermal insulation project. Subject to compliance with SNiP, thermal insulation of pipelines will be carried out efficiently without violating standards. Thermal insulation pipelines SNiP is provided for linear sections of pipelines, heating networks, compensators and pipe supports. Insulation of pipelines in residential buildings, industrial buildings requires strict compliance with design standards and fire safety systems.

The quality of materials must comply with SNiP, thermal insulation of pipelines should be aimed at reducing heat loss.

The main tasks of thermal insulation, features of the choice of materials

The main purpose of thermal insulation is to reduce heat loss in heating systems or hot water pipelines. The main function of insulation is aimed at preventing condensation. Condensation can form both on the surface of the pipe and in the insulating layer. In addition, according to safety standards, the insulation of pipelines must ensure a certain temperature on the insulation surface, and in case of stagnation of water, protect it from freezing and icing in the winter.

Insulation of pipelines also increases the service life of pipes.

According to SNiP standards, thermal insulation of pipelines is used both for central heating, and reduces heat loss from intra-house heating networks. What to consider when choosing thermal insulation:

• Pipe diameter. It depends on what type of insulator will be used. Pipes can be cylindrical, half-cylinders or soft mats in rolls. Insulation of small diameter pipes is mainly carried out using cylinders and half-cylinders.
• Coolant temperature.
• Conditions in which the pipes will be operated.

Types of insulation

Let's consider the most popular and frequently used materials for thermal insulation:

1. Fiberglass. Glass fiber materials are often used for above-ground piping because they have a long service life. Fiberglass has a low application temperature and is characterized by low density. High-quality fiberglass has high vibration, chemical and biological resistance.
2. Mineral wool. Insulation of pipelines with mineral wool is a very effective heat insulator. This insulating material will be used in different conditions. Unlike fiberglass, which has a low application temperature (up to 180ºC), mineral wool can withstand temperatures up to 650ºC. At the same time, its heat-insulating and mechanical properties are preserved. Mineral wool does not lose its shape and is highly resistant to chemicals and acid. This material is non-toxic and has a low degree of moisture absorption.

In turn, mineral wool comes in two forms: stone and glass.

Insulation of pipelines using mineral wool mainly used in residential buildings, public and household premises, as well as to protect surfaces that are exposed to heat.

1. Polyurethane foam has a wide range of applications, but is quite expensive material. According to SNiP standards, thermal insulation of pipelines is environmentally friendly and does not affect human health. Polyurethane foam is resistant to impact external factors, non-toxic and quite durable.
2. Expanded polystyrene. In some areas of industry, foam plastic is an indispensable material, as it has low thermal conductivity and moisture absorption and a long service life. Expanded polystyrene is difficult to ignite and is an excellent sound insulator.
3. In addition to the above materials, pipeline insulation can be carried out using other less well-known, but no less practical insulation materials, such as foam glass and penoizol. These materials are durable, safe and are close relatives of polystyrene foam.

Thermal insulating paint can also provide protection against corrosion and high thermal insulation of pipes.

It's relative new material, the main advantage of which is that it penetrates into hard-to-reach places and is able to withstand high temperature changes.

dom-data.ru

Features of thermal insulation of pipelines for heating networks: standards, materials, technology

When laying pipelines prerequisite is to perform work on thermal insulation of networks. This applies to all pipelines - not only water supply, but also sewerage systems. The need for this is due to the fact that winter time Water passing through pipes may freeze. And if coolant circulates through the communications, this leads to a decrease in its temperature. To minimize heat loss, when laying pipelines they resort to installing a heat-insulating layer. What materials and methods can be used for thermal insulation of networks - this will be discussed in this article.

Thermal insulation of pipelines: ways to solve the problem

Provide effective protection for pipeline systems from environmental factors, mainly from the outside air temperature, is possible if the following measures are taken:

Since the last method is most often used, it makes sense to talk about it in more detail.

Standards for thermal insulation of pipelines

Requirements for thermal insulation of equipment pipelines are formulated in SNiP. IN regulatory documents contained detailed information about materials, which can be used for thermal insulation of pipelines, and in addition methods of work. In addition, the regulatory documents indicate standards for thermal insulation circuits, which are often used to insulate pipelines.

• regardless of the temperature of the coolant, any pipeline system must be insulated;
• Both ready-made and prefabricated structures can be used to create a thermal insulation layer;
• Corrosion protection must be provided for metal parts of pipelines.

It is desirable to use a multilayer circuit design when insulating pipelines. It must include the following layers:

• insulation;
• vapor barrier;
• protection made of dense polymer, non-woven fabric or metal.

In some cases, reinforcement can be built that eliminates the collapse of materials and, in addition, prevents pipe deformation.

Note that most of the requirements contained in regulatory documents relate to the insulation of main pipelines high power. But even in the case of installing household systems, it would be useful to familiarize yourself with them and take them into account when installing water supply and sewerage systems on your own.

Materials for thermal insulation of pipelines

Currently, the market offers a large selection of materials that can be used for pipeline insulation. Each of them has its own advantages and disadvantages, and in addition, application features. To choose the right heat insulator, you need to know all this.

Polymer insulation

When the task is to create effective system thermal insulation of pipelines, most often attention is paid to foam-based polymers. A large assortment allows you to choose the right material, thanks to which you can provide effective protection from the external environment and eliminate heat loss.

If we talk in more detail about polymer materials, the following can be distinguished from those available on the market.

Polyethylene foam.

The main characteristic of the material is low density. In addition, it is porous and has high mechanical strength. This insulation is used for the manufacture of cylinders with a cut. Their installation can be carried out even by people far from the field of thermal insulation of pipelines. However, this material has one drawback: structures made of polyethylene foam wear out quickly and, in addition, have poor heat resistance.

If polyethylene foam cylinders are selected for thermal insulation of pipelines, then Special attention it is necessary to pay attention to their diameter. It must match the diameter of the collector. Taking this rule into account when choosing an insulation design, it is possible to exclude spontaneous removal of polyethylene foam casings.

Expanded polystyrene.

The main feature of this material is elasticity. It is also characterized by high strength indicators. Protective products for thermal insulation of pipelines made from this material are produced in the form of segments that resemble a shell in appearance. Special locks are used to connect parts. They have tongues and grooves, which ensure quick installation of these products. The use of polystyrene foam shells with technical locks eliminates the occurrence of “cold bridges” after installation. In addition, during installation there is no need to use additional fasteners.

Polyurethane foam.

This material is used mainly for pre-installed thermal insulation of heating network pipelines. However, it can also be used to insulate household pipeline systems. This material is available in the form of foam or shell, which consists of two or four segments. Spray insulation provides reliable thermal insulation with a high degree of tightness. The use of such insulation is most suitable for communication systems with a complex configuration.

When using polyurethane foam in the form of foam for thermal insulation of pipelines of heating networks, you need to know that it is destroyed under the influence of ultraviolet rays. Therefore, in order for the insulating layer to last a long time, it is necessary to ensure its protection. To do this, apply a layer of paint on top of the foam or lay a non-woven fabric with good permeability.

Fibrous materials

Insulation materials of this type are mainly represented by mineral wool and its varieties. Currently, they are most popular among consumers as insulation. Materials of this type are also in high demand, like polymer materials.

Thermal insulation made using fiber insulation has certain advantages. These include the following:

• low thermal conductivity coefficient;
• resistance of the thermal insulation material to aggressive substances such as acids, alkalis, oil;
• the material is able to maintain a given shape without an additional frame;
• the cost of insulation is quite reasonable and affordable for most consumers.

Please note that during work on thermal insulation of pipelines with such materials, it is necessary to prevent compression of the fiber when laying the insulation. It is also important to ensure that the material is protected from moisture.

Products made from polymer and mineral wool insulation for thermal insulation in some cases can be covered with aluminum or steel foil. The use of such screens reduces heat dissipation.

Multilayer structures for pipeline protection

Often, to insulate pipelines, thermal insulation is installed using the “pipe-in-pipe” method. When using this scheme, a heat-protective casing is installed. The main task of the specialists installing such a circuit is to correctly connect all the parts into a single structure.

Upon completion of the work, the result is a design that looks like this:

• the basis of the heat-protective circuit is a pipe made of metal or polymer material. It is the supporting element of the entire device;
• The thermal insulation layers of the structure are made of foamed polyurethane foam. The material is applied using pouring technology; the molten mass is filled into a specially created formwork;
• protective casing. Pipes made of galvanized steel or polyethylene are used for its manufacture. The first ones are used for laying networks in open space. The latter are used in cases where pipeline systems are laid in the ground using ductless technology. In addition, often when creating this type of protective casing, insulation based on polyurethane foam is placed copper conductors, the main purpose of which is remote control condition of the pipeline, including the integrity of the thermal insulation layer;
• If the pipes arrive at the installation site in assembled form, then the welding method is used to connect them. Specialists use special heat-shrinkable cuffs to assemble the heat-protective circuit. Or, overhead couplings made from mineral wool, which are covered with a layer of foil, can be used.

Do-it-yourself thermal insulation of pipelines

There are a number of factors on which the technology for creating a thermal insulation layer on pipelines may depend. One of the most important is how the collector is laid - outside or in the ground.

Insulation of underground networks

To solve the problem of ensuring thermal protection of buried communications, insulation work is carried out in the following order:

Thermal insulation of external pipeline

In accordance with existing standards, pipelines located on the surface of the earth are thermally insulated as follows:

• insulation work begins with all parts being cleaned of rust;
• Next, the pipes are treated with an anti-corrosion compound. After this, they proceed to installing a polymer shell, followed by wrapping the pipes with rolled mineral wool insulation;
• Please note that a layer of polyurethane foam can be used to cover the structure, or the structure can be covered with several layers of heat-insulating paint;
• The next step is to wrap the pipe as in the previous option.

Along with fiberglass, other materials can be used, for example, foil film with polymer reinforcement. When this work is completed, the structures are secured using steel or plastic clamps.

Thermal insulation of pipelines is an important task that must be carried out when laying communications. There are many materials and technologies for its implementation. By selecting suitable way thermal insulation, it is necessary to adhere to the work technology. In this case, heat loss will be minimal, and in addition, the pipeline structure will be protected from various factors, which will have a positive effect on their service life.

kotel.guru

Today, thermal insulation of pipelines is necessary both to reduce heat losses of the corresponding systems and to lower the temperature of communications for their safe use. In addition, without it it is difficult to ensure normal operation of networks in winter, since the likelihood of freezing and failure of pipes is quite high and also dangerous.

According to existing standards, as well as rules for safe operation steam and hot water supply pipes, for pipeline elements with a wall temperature of more than 55 degrees and at the same time they are located in accessible places, it is recommended to use additional thermal insulation in order to reduce their heating. In view of this, when calculating the thickness protective coating laid indoors, the heat flux density standards are taken as a basis. In some cases, the temperature of the outer part of the insulation itself is also taken into account.

How to calculate insulation?

The choice of the required insulation is carried out on the basis of mathematical calculations, from which it is clear which material is better to take, its thickness, composition and other characteristics. If everything is done correctly, then it is quite possible to significantly reduce heat losses, as well as make the operation of systems reliable and absolutely safe.

Figure No. 1. Thermal insulation of pipes with foam plastic

What to pay attention to during calculations:

• - difference in ambient temperatures where communications are used;
• - the temperature of the surface that is supposed to be insulated;
• - possible loads on the pipes;
• - mechanical impacts from external influences, be it pressure, vibration, etc.;
• - the value of the thermal conductivity coefficient of the insulation used;
• - impact and corresponding magnitude from transport and soil;
• - the ability of the insulator to resist various types of deformation.

It should be noted that SNiP 41-03-2003 is considered the main document on the basis of which materials for insulation and their thickness are selected, according to specific operating conditions. The same SNiP states that for networks in which the operating temperature of the pipes is less than 12 degrees, it is necessary to additionally lay a vapor barrier when treating the surface.

Thermal insulation of pipes can be calculated in two ways, and each option can be called reliable and convenient for specific conditions. We are talking about an engineering (formula) and online version.

In the first case, the actual thickness of the optimal insulating layer is determined by a technical and economic calculation, in which the main parameter is temperature resistance. The corresponding value should be within 0.86ºC m²/W in the case of pipes with a diameter of up to 25mm, and at least 1.22ºC m²/W - from 25mm and above. SNiP provides special formulas by which the total temperature resistance of the insulating composition of cylindrical pipes is calculated.

Please note that if you have any doubts about the correctness of the calculation, it is better to seek help and advice from specialists who will carry out the work reliably and efficiently, especially since the prices for their services are quite reasonable. Otherwise, a situation may arise where the scope of certain actions may be more costly in terms of money than doing everything from scratch.

When performing the work yourself, you should also understand that all calculations of the thickness of pipe insulation are made under certain operating conditions, which take into account the materials themselves, temperature changes, and humidity.

The second method is implemented through online calculators, of which there are countless today. Such an assistant is usually free, simple and convenient. Often it also takes into account all the norms and requirements of SNiP, according to which professionals perform calculations. All calculations are carried out quite quickly and accurately. Figuring out how to use the calculator will be easy.

Initially, the required task is selected:

• 1. Preventing liquid freezing of utility pipelines.
• 2. Ensuring a constant operating temperature of protective insulation.
• 3. Insulation of communications of water heating networks of two-pipe underground channel gaskets.
• 4. Protection of the pipeline from the formation of condensation on the insulator.

Then you need to enter the main parameters by which the calculation is carried out:

• 1. Pipe outer diameter.
• 2. Preferred insulating component.
• 3. The time during which water crystallizes in an inert state.
• 4. Temperature indicator of the surface to be insulated.
• 5. Coolant temperature value.
• 6. Type of coating used (metal or non-metal).

After entering all the data, the calculation result appears, which can be used as a basis for subsequent construction and selection of materials.

Figure No. 2. Thermal insulation of central heating pipes

The right choice of insulation

The main reason for freezing of pipes is the low circulation rate of working fluids in them. A negative factor is the freezing process, which can lead to irreversible and catastrophic consequences. This is why thermal insulation of networks is extremely necessary.

Particular attention should be paid to this aspect in pipelines that operate periodically, be it water supply from a well or a country house. water heating. In order not to have to restore working systems in the future, it is still better to carry out their timely thermal insulation.

Until recently, insulation work was carried out using a single technology, with fiberglass used as a protective element. Currently, we offer a huge selection of all kinds of heat insulators designed for a specific type of pipe, having different specifications and composition.

Due to their intended use, it would be wrong to compare materials and say that one is better than the other. For this reason, below we will reveal the insulators that exist today.

According to the component representation option:

• - sheet;
• - roll;
• - filling
• - casing;
• - combined.

By area of ​​use:

• - for water drainage and sewerage;
• - for steam, heating, hot and cold water supply networks;
• - for ventilation pipelines and freezing units.

Any thermal insulation is characterized by its resistance to fire and its thermal conductivity.

• 1. Shell. Its advantage is ease of installation, optimal characteristics And high quality execution. It has low thermal conductivity, fire resistance, and a minimal level of moisture absorption. Suitable for protecting heating networks and water supply systems.

Figure No. 3. Shell pipe insulation

• 2. Mineral wool. It is usually supplied in rolls and is used for processing pipes whose coolant has a very high temperature. This option is only advisable for small processing areas, since mineral wool is quite an expensive material. Its installation is carried out by winding communications and fixing them in a given position with wire made of of stainless steel or twine. Additionally, it is recommended to carry out waterproofing, since cotton wool easily absorbs moisture.

Figure No. 4. Insulation mineral wool cylinder

• 3. Expanded polystyrene. The design of thermal insulation of this type is more like two halves, or a shell, through which the pipeline is insulated. The option can safely be called high-quality and convenient in terms of installation. Due to minimal moisture absorption and low thermal conductivity, high fire resistance, minimal thickness, polystyrene foam is excellent for protecting heating and water supply networks.

Figure No. 5. Foam insulation

• 4. Penoizol. Thermal insulation has similar parameters to polystyrene foam, although with a significant difference in installation. Application is carried out using an appropriate sprayer, since the material is in a liquid state. After complete drying, the entire treated surface of the pipe acquires a dense and durable hermetic structure that reliably maintains the temperature of the coolant. A significant advantage is that there is no need to use additional fasteners to secure the material. The only downside is that it is expensive.

Figure No. 6. Insulation of pipes with foam insulation

• 5. Penofol with foil base. An innovative product that is becoming more popular every day. It consists of polyethylene foam and aluminum foil. The two-layer design allows both maintaining the temperature of the networks and heating the space, since the foil is able to reflect and accumulate heat. We especially pay attention to the low combustion ability, high environmental data, ability to withstand high humidity and significant temperature changes.

Figure No. 7. Pipe insulated with foil penofol

• 6. Foamed polyethylene. Thermal insulation of this type is very common, and it is often found on water mains. A special feature is the ease of installation, for which it is enough to cut right size material and wrap it around the production line, fixing it with tape. Foamed polyethylene is often supplied in the form of a wrap for a pipe of a certain diameter with a technological cut, which is put on the desired section of the system.

Figure No. 8. Foamed polyethylene

It is important to know that when insulating pipelines, all insulation materials, except penoizol, require the additional use of waterproofing and adhesive tape for fixation.

From all of the above, it is clear that there are quite a lot of options for processing pipes, and the choice is very large. Experts advise paying attention to the conditions in which each material will be used, its characteristics and installation method. Naturally, competent thermal insulation calculations also play an important role, which will allow you to be confident in the work done.

Video No. 1. Thermal insulation of pipes. Installation example

Methods of thermal insulation of pipelines

SNiP specifications and many professionals recommend following the following options for protecting trunk lines:

• 1. Air insulation. Typically, communication systems running in the ground are protected by thermal insulation of a certain thickness. However, the factor that the freezing of the ground goes from the top to the bottom is often not taken into account, while the heat flow from the pipes tends to the top. Since the pipeline is protected on all sides by a component of minimal thickness, the rising heat is also insulated. More rational in in this case install insulation over the upper part of the line so that a thermal layer is formed.
• 2. Use of insulation and heating element. Great as an alternative traditional options. In this case, the point is taken into account that the protection of lines is seasonal, and laying them in the ground is not rational for financial reasons, as is the use of a large thickness of insulator. According to SNiP rules and manufacturers' instructions, the cable can be located both inside and outside the pipes.
• 3. Laying a pipe in a pipe. Here, in polypropylene pipes additionally separate pipes are installed. The peculiarity of the method is that it is possible to warm up the systems almost always, including using the principle of suction of warm air masses. In addition, if necessary, an emergency hose can easily be laid in the existing gap.

Conclusion

Summarizing all of the above, we can say that there are a lot important points and nuances for processing and protecting the pipeline. In any situation, it is always better to start by calculating the required insulation, choosing its type, thickness and cost. The option of its installation also plays an important role, since the most problematic conditions will require additional significant cash injections into the construction of the necessary systems.

A perfect approach to the selection of thermal insulation can ultimately lead to minimal costs and a reduction in the complexity of the work performed. High-quality selection of the required insulating components will effectively maintain the temperature of the coolant in the pipes, as well as significantly increase their service life.

Video No. 2. Universal thermal insulation for pipes

Today, thermal insulation of pipelines is necessary both to reduce heat losses of the corresponding systems and to lower the temperature of communications for their safe use. In addition, without it it is difficult to ensure normal operation of networks in winter, since the likelihood of freezing and failure of pipes is quite high and also dangerous.

According to existing standards, as well as rules for the safe operation of steam and hot water supply pipes, for pipeline elements with a wall temperature of more than 55 degrees and at the same time they are located in accessible places, it is recommended to use additional thermal insulation in such a way as to reduce their heating. In view of this, when calculating the thickness of the protective coating laid in a room, heat flux density standards are taken as a basis. In some cases, the temperature of the outer part of the insulation itself is also taken into account.

How to calculate insulation?

The choice of the required insulation is carried out on the basis of mathematical calculations, from which it is clear which material is better to take, its thickness, composition and other characteristics. If everything is done correctly, then it is quite possible to significantly reduce heat losses, as well as make the operation of systems reliable and absolutely safe.

What to pay attention to during calculations:

1. difference in ambient temperatures where communications are used;
2. the temperature of the surface that is supposed to be insulated;
3. possible loads on the pipes;
4. mechanical impacts from external influences, be it pressure, vibration, etc.;
5. the value of the thermal conductivity coefficient of the insulation used;
6. impact and corresponding magnitude from transport and soil;
7. the ability of an insulator to resist various types of deformation.

It should be noted that SNiP 41-03-2003 is considered the main document on the basis of which materials for insulation and their thickness are selected, according to specific operating conditions. The same SNiP states that for networks in which the operating temperature of the pipes is less than 12 degrees, it is necessary to additionally lay a vapor barrier when treating the surface.

Thermal insulation of pipes can be calculated in two ways, and each option can be called reliable and convenient for specific conditions. We are talking about an engineering (formula) and online version.

In the first case, the actual thickness of the optimal insulating layer is determined by a technical and economic calculation, in which the main parameter is temperature resistance. The corresponding value should be within 0.86ºC m²/W in the case of pipes with a diameter of up to 25mm, and at least 1.22ºC m²/W - from 25mm and above. SNiP provides special formulas by which the total temperature resistance of the insulating composition of cylindrical pipes is calculated.

Please note that if you have any doubts about the correctness of the calculation, it is better to seek help and advice from specialists who will carry out the work reliably and efficiently, especially since the prices for their services are quite reasonable. Otherwise, a situation may arise where the scope of certain actions may be more costly in terms of money than doing everything from scratch.

When performing the work yourself, you should also understand that all calculations of the thickness of pipe insulation are made under certain operating conditions, which take into account the materials themselves, temperature changes, and humidity.

The second method is implemented through online calculators, of which there are countless today. Such an assistant is usually free, simple and convenient. Often it also takes into account all the norms and requirements of SNiP, according to which professionals perform calculations. All calculations are carried out quite quickly and accurately. Figuring out how to use the calculator will be easy.

Initially, the required task is selected:

• Preventing liquid freezing in utility pipelines.
• Ensuring a constant operating temperature of protective insulation.
• Insulation of communications of water heating networks of two-pipe underground channel laying.
• Protection of the pipeline from the formation of condensation on the insulator.

Then you need to enter the main parameters by which the calculation is carried out:

• Pipe outer diameter.
• Preferred insulation component.
• The time during which water crystallizes in an inert state.
• Temperature indicator of the surface to be insulated.
• Coolant temperature value.
• Type of coating used (metal or non-metal).

After entering all the data, the calculation result appears, which can be used as a basis for subsequent construction and selection of materials.

The right choice of insulation

The main reason for freezing of pipes is the low circulation rate of working fluids in them. A negative factor is the freezing process, which can lead to irreversible and catastrophic consequences. This is why thermal insulation of networks is extremely necessary.

Particular attention should be paid to this aspect in pipelines that operate periodically, be it water supply from a well or country water heating. In order not to have to restore working systems in the future, it is still better to carry out their timely thermal insulation.

Until recently, insulation work was carried out using a single technology, with fiberglass used as a protective element. Currently, a huge selection of all kinds of heat insulators are offered, designed for a specific type of pipe, having different technical characteristics and composition.

Due to their intended use, it would be wrong to compare materials and say that one is better than the other. For this reason, below we will reveal the insulators that exist today.

According to the component representation option:

• sheet;
• roll;
• pouring
• casing;
• combined.

By area of ​​use:

• for water drainage and sewerage;
• for steam, heating, hot and cold water supply networks;
• for ventilation pipelines and freezing units.

Any thermal insulation is characterized by its resistance to fire and its thermal conductivity.

• Shell. Its advantage is ease of installation, optimal characteristics and high quality workmanship. It has low thermal conductivity, fire resistance, and a minimal level of moisture absorption. Suitable for protecting heating networks and water supply systems.

• Mineral wool. It is usually supplied in rolls and is used for processing pipes whose coolant has a very high temperature. This option is only advisable for small processing areas, since mineral wool is quite an expensive material. Its installation is carried out by winding communications and fixing them in a given position with stainless steel wire or twine. Additionally, it is recommended to carry out waterproofing, since cotton wool easily absorbs moisture.

• Expanded polystyrene. The design of thermal insulation of this type is more like two halves, or a shell, through which the pipeline is insulated. The option can safely be called high-quality and convenient in terms of installation. Due to minimal moisture absorption and low thermal conductivity, high fire resistance, minimal thickness, polystyrene foam is excellent for protecting heating and water supply networks.

• Penoizol. Thermal insulation has similar parameters to polystyrene foam, although with a significant difference in installation. Application is carried out using an appropriate sprayer, since the material is in a liquid state. After complete drying, the entire treated surface of the pipe acquires a dense and durable hermetic structure that reliably maintains the temperature of the coolant. A significant advantage is that there is no need to use additional fasteners to secure the material. The only downside is that it is expensive.

• Penofol with foil base. An innovative product that is becoming more popular every day. It consists of polyethylene foam and aluminum foil. The two-layer design allows both maintaining the temperature of the networks and heating the space, since the foil is able to reflect and accumulate heat. We especially pay attention to the low combustion ability, high environmental data, the ability to withstand high humidity and significant temperature changes.

• Foamed polyethylene. Thermal insulation of this type is very common, and it is often found on water mains. A special feature is the ease of installation, for which it is enough to cut the required size of the material and wrap it around the production line, fixing it with tape. Foamed polyethylene is often supplied in the form of a wrap for a pipe of a certain diameter with a technological cut, which is put on the desired section of the system.

It is important to know that when insulating pipelines, all insulation materials, except penoizol, require the additional use of waterproofing and adhesive tape for fixation.

From all of the above, it is clear that there are quite a lot of options for processing pipes, and the choice is very large. Experts advise paying attention to the conditions in which each material will be used, its characteristics and installation method. Naturally, competent thermal insulation calculations also play an important role, which will allow you to be confident in the work done.

Video No. 1. Thermal insulation of pipes. Installation example

Methods of thermal insulation of pipelines

SNiP specifications and many professionals recommend following the following options for protecting trunk lines:

1. Air insulation. Typically, communication systems running in the ground are protected by thermal insulation of a certain thickness. However, the factor that the freezing of the ground goes from the top to the bottom is often not taken into account, while the heat flow from the pipes tends to the top. Since the pipeline is protected on all sides by a component of minimal thickness, the rising heat is also insulated. In this case, it is more rational to install insulation over the upper part of the line, so that a thermal layer is formed.
2. Use of insulation and heating element. Great as an alternative to traditional options. In this case, the point is taken into account that the protection of lines is seasonal, and laying them in the ground is not rational for financial reasons, as is the use of a large thickness of insulator. According to SNiP rules and manufacturers' instructions, the cable can be located both inside and outside the pipes.
3. Laying a pipe in a pipe. Here, individual pipes are additionally installed in polypropylene pipes. The peculiarity of the method is that it is possible to warm up the systems almost always, including using the principle of suction of warm air masses. In addition, if necessary, an emergency hose can easily be laid in the existing gap.

Conclusion

Summarizing all of the above, we can say that there are a lot of important points and nuances for processing and protecting the pipeline. In any situation, it is always better to start by calculating the required insulation, choosing its type, thickness and cost. The option of its installation also plays an important role, since the most problematic conditions will require additional significant cash injections into the construction of the necessary systems.

Thermal insulation materials and structures are designed to reduce heat loss by pipelines and equipment of heating networks, maintain a given temperature of the coolant, and also prevent high temperature on the surface of heat pipes and equipment.

Reducing transport heat losses is the main means of saving fuel Considering the relatively low costs of thermal insulation of pipelines (5...8% of capital investments in the construction of heating networks), it is very important in matters of preserving transported heat through pipelines to cover them with high-quality and effective thermal insulation materials .

Thermal insulation materials and structures are in direct contact with environment, characterized by fluctuations in temperature, humidity, and in underground installations - aggressive actions of groundwater in relation to the surface of the pipes

Thermal insulation structures are made from special materials, the main property of which is low thermal conductivity. There are three groups of materials depending on thermal conductivity: low thermal conductivity up to 0.06 W/(mV°C) with an average temperature of the material in the structure of 25°C and not more than 0.08 W/(m*°С) at 125°С; average thermal conductivity 0.06.. 0.115 W/(m-°C) at 25°C and 0.08...0.14 W/(mv°C) at 125°C; increased thermal conductivity 0.115...OD75 W/(m-°C) at 25°C and 0.14.0.21 W/(m-°C) at 125°C.

In accordance with the main layer of thermal insulation structures for all types of gaskets except non-layered ones, materials with an average density of no more than 400 kg/m3 and a thermal conductivity of no more than 0.07 W/(m*°C) should be used at a material temperature of 25°C. For ductless installation - respectively, no more than 600 kg/m3 and 0.13 W/(mV°C)

Another important property of thermal insulation materials is their resistance to temperatures up to 200°C, while they do not lose their physical properties and structures. Materials must not decompose with the release of harmful substances, as well as substances that contribute to corrosion of the surface of pipes and equipment (acids, alkalis, corrosive gases, sulfur compounds, etc.)

For this reason, the use of boiler slag containing sulfur compounds in its composition is not allowed for the manufacture of thermal insulation.

Also important properties are water absorption and hydrophobicity (water repellency). Moisturizing thermal insulation sharply increases its thermal conductivity coefficient due to the displacement of air by water. In addition, oxygen and carbon dioxide dissolved in water contribute to corrosion of the outer surface of pipes and equipment.

The air permeability of the thermal insulation material must also be taken into account when designing and manufacturing the thermal insulation structure, which must have appropriate tightness, preventing the penetration of moist air

Thermal insulation materials must also have increased electrical resistance, preventing stray currents from reaching the surface of pipelines, especially with channelless installations, which causes electrical corrosion of pipes

Thermal insulation materials must be sufficiently bio-resistant, not subject to rotting, the action of rodents and changes in structure and properties over time

Industrialism in the design of thermal insulation structures is one of the main characteristics of thermal insulation materials. Coating of pipelines with thermal insulation must, however, be carried out in factories using a mechanized method. This significantly reduces labor costs, installation time and improves the quality of the thermal insulation structure. Insulation of butt joints, equipment, branches and shut-off valves must be produced using previously prepared parts with mechanized assembly at the installation site.

The thermal properties of thermal insulation materials deteriorate as their density increases, so mineral wool products should not be subjected to excessive compaction. Thermal insulation fastening parts (bandages, mesh, wire, ties) must be used from aggressively resistant materials or with an appropriate coating that resists corrosion.

And, finally, thermal insulation materials and structures must be low cost, and their use must be economically justified.

THERMAL INSULATION MATERIALS, PRODUCTS AND STRUCTURES FOR ABOVE AND UNDERGROUND LAYING OF HEATING NETWORKS IN CHANNELS

Thermal insulation materials

Main thermal insulation material Currently, mineral wool and products made from it are used for thermal insulation of pipelines and heating network equipment. Mineral wool is a fine-fiber material obtained from molten rocks, metallurgical slag, or a mixture thereof. In particular, basalt wool and products made from it are widely used.

Mineral wool is made by compacting and adding synthetic or organic (bitumen) binders or stitching various mats, slabs, half-cylinders, segments and cords with synthetic threads.

Stitched mineral wool mats are made without linings and with linings from asbestos fabric, fiberglass, fiberglass canvas, corrugated or roofing cardboard; packaging or sack paper.

Depending on the density, hard, semi-rigid and soft products are distinguished. Cylinders with a cut along the generatrix, half-cylinders for insulating pipes of small diameters (up to 250 mm) and segments for pipes with a diameter of more than 250 mm are made from rigid materials. To insulate pipes of large diameters, vertically layered mats glued to the covering material are used, as well as pierced mats made of mineral wool on a metal mesh.

For thermal insulation at the installation site of pipeline joints, as well as compensators, shut-off valves, a thermal insulating cord is made from mineral wool, which is a mesh tube, usually made of fiberglass, densely filled with mineral wool. The thermal conductivity of mineral wool products depends on the brand (density) and ranges from 0.044...0.049 W/(m*°C) at a temperature of 25°C and 0.067. ..0.072 W/(m*°С) at a temperature of 125°С

Glass wool is a fine-fiber material obtained from a molten glass charge by continuous stretching of glass fiber, as well as by the centrifugal-spun-blown method. Hard, semi-rigid and soft slabs and mats are made from glass wool by molding and gluing with synthetic resins. Mats and slabs without a binder are also produced, stitched with glass or synthetic thread

The thermal conductivity coefficient of glass wool products also depends on the density and ranges from 0.041...0.074 W/(m-°C)

Fiberglass canvas (non-woven roll material with a synthetic binder) and canvas-stitched canvas made from waste glass fiber, which is mhoi layered canvas stitched with glass filaments, are widely used as wrapping and covering materials.

Vulcanite products are produced by mixing diatomite, quicklime and asbestos, molding and processing in autoclaves. They produce slabs, semi-cylinders and segments for insulation of pipelines DN 50...400. Thermal conductivity of products from 0.077 W/(m*°C) at 25°C to 0.1 W/(m-°C) at 125°C Limestone materials - a finely ground mixture of quicklime, siliceous material (diaumite, tripolite, quartz sand) and asbestos. Products are also produced in the form of slabs, segments and semi-cylinders for insulating pipelines DN 200...400. Thermal conductivity of the material is from 0.058 W/(m-°C) at 25°C to 0.077 W/(m*°C) at 125°C

Perlite is a porous material obtained by heat treatment volcanic glass with inclusions of feldspars, quartz, plagioclase. Other silicate rocks of volcanic origin (obsidian, pumice, tuff, etc.) are used as raw materials for producing expanded perlite. In the form of crushed stone and sand, perlite is used as a filler for the preparation of thermal insulating concrete and other thermal insulating products, such as for example, bitumen perlite.

By mixing perlite sand with cement and asbestos by molding, perlite cement products are obtained in the form of half-cylinders, slabs and segments. Thermal conductivity coefficient from 0.058 W/(m*°C) at 25°C to 128 W/(m*°C) at 300°C.

Foam plastics are increasingly used as the main thermal insulation layer. Foams are porous gas-filled polymer material. Their manufacturing technology is based on foaming polymers with gases formed as a result of chemical reactions between individual miscible components. Foam plastics allowed for use for insulation of heat pipelines include phenol-formaldehyde foams FRP-1 and resopen, made from resol resin FRP-1A or resocel and the foaming component VAG-3. Cylinders, half-cylinders, segments, insulated fittings of the FRP-1 and Rezopen brands are made from this material. Thermal conductivity is 0.043...0.046 at 20°C.

Also promising is the use of polyurethane foam materials obtained by mixing various polyesters, isocyanates and foaming additives.

Foam insulation is applied in factories by pouring into molds or spraying onto the surface of pipes. Insulation of joints, fittings, fittings, etc. is possible at the installation site of the pipeline by pouring liquid foam into the formwork or shells, followed by rapid hardening of the foam insulation.

For example, polyurethane foam thermal and waterproofing PPU 308 N developed by VNIPIenergoprom has a thermal conductivity coefficient equal to 0.032 W/(m*°C) with a density of 40...90 kg/m3, it is applied to pipes using a mechanized method, and does not require an anti-corrosion coating. The outer layer with a density of 150...400 kg/m3 with a compressive strength of 50 kg/cm2 is used as a covering layer

Thermal insulation structures

Thermal insulation structures include a protective coating on the pipe surface from corrosion, a main insulation layer (several layers) and a protective coating (cover layer) that protects the main thermal insulation layer from mechanical damage, exposure atmospheric precipitation and aggressive environments. The protective coating also includes means and details for fastening the covering layer and insulation as a whole.

The choice of protective coating for the surface of pipes against corrosion is made depending on the installation method, the type of aggressive influences on the surface and the design of thermal insulation (Appendix 5).

The most common are oil-bitumen coatings on the ground, as well as coatings with isol or brizol on insulating mastic.

A glass-enamel coating consisting of a mixture of quartz sand, feldspar, alumina, borax and soda is very effective. To increase adhesion to the metal, oxides of nickel, chromium, copper and other additives are added to the composition. A thick aqueous composition is applied to the surface of the pipe, dried and melted on the surface of the pipe in a ring electromagnetic inductor at a temperature of about 800°C. Butt joints of pipes can be coated with enamel using mobile installations. An inexpensive anti-corrosion agent is coating with EFAZhS paint on epoxy resin. Others are used epoxy enamels For heat pipelines located in harsh temperature and humidity conditions, metallization of the surface with aluminum using a gas-thermic method is very effective. Aluminum coating is applied to the surface of the pipe using gas-flame or electric arc apparatus with a gas or air jet. An installation for metallization with aluminum can be included in a flow-mechanized line according to pipe thermal insulation

Before applying the anti-corrosion coating, the surface of the pipes is cleaned of corrosion and scale with mechanical brushes or sandblasters and, if necessary, degreased with organic solvents

Fully prefabricated thermal insulation structures - the most industrial type of insulation - are manufactured at the factory with anti-corrosion treatment of pipes and with the fastening of a covering layer on top of the main layer of insulation. Insulation of joints, fittings, fittings, compensators, etc. is carried out after installation of all elements of the heating network section from piece heat-insulating materials prepared at the factory products.

Prefabricated complete thermal insulation structures are a complete set of thermal insulation products, coating elements and fasteners in size and diameter.

Appendix 4 shows fully prefabricated and complete thermal insulation structures for heating networks.

Suspended thermal insulation structures are the main method of thermal insulation of heat pipelines of above-ground and underground channel gaskets. It is made from mineral wool products, glass wool, vulcanite products, lime-silicon and other materials. Appendices 1 and 2 show the permissible materials for the main insulation layer depending on the method of laying the heating network.

Currently, the manufacture of suspended thermal insulation structures, as a rule, is carried out by assembling piece blanks with fastening with a covering layer and fastening parts. The assembly of insulating structures at the installation site from ready-made elements (segments, strips, mats, shells and half-cylinders) involves a lot of manual labor.

When installing thermal insulation from soft materials(slabs, mats) when applying the covering layer, compaction of the material of the heat-insulating layer is inevitable. This must be taken into account when calculating the required amount of material by the compaction coefficient (Appendix 8).

To insulate shut-off valves, removable printed insulation structures in the form of mattresses filled with mineral or glass wool, perlite and other heat-insulating material are used. The mattress shell is made of fiberglass.

When laid above ground in the open air, the covering layer, as a rule, serves as a protective coating against the penetration of atmospheric moisture. Folgoizol, foil-roofing material, reinforced plastic materials, fiberglass, fiberglass, carbon steel sheets and galvanized sheets, sheets, tapes and foil of aluminum alloys are used (Appendices 6 and 7).

When laying in non-passable channels, cheaper reinforced plastic materials, fiberglass, fiberglass, glass ruberoid, and roofing felt are used. In tunnels it is also allowed to use folgoizol, foilrubsroid and duplicated aluminum foil.

When choosing a material for a protective coating, depending on the method of laying heat pipes, you should be guided by the standards.

Fastening the cover layer from sheet metal produced with self-locking screws, strips or bandages made of packaging tape or aluminum alloy tapes, shells made of fiberglass, foil and other materials, secured with bandages made of aluminum or packaging tape, galvanized steel tape and wire. The roofing steel covering is painted with weather-resistant paints.

In Fig. 1 shows an example of thermal insulation of a pipeline with mineral wool slabs.

Wrapping structures are made of tufted mats or soft boards on a synthetic bond, which are sewn together with transverse and longitudinal seams. The covering layer is attached in the same way as in suspended insulation

Wrapping structures in the form of thermal insulating strands made of mineral or glass wool, after applying them to the surface, are also covered with a protective layer. Insulate joints, fittings, fittings.

Mastic insulation is also used for thermal insulation at the installation site of fittings and equipment. Powdered materials are used: asbestos, asbozurt, sovelit. The mixture mixed with water is applied to the preheated insulated surface manually. Mastic insulation is rarely used, as a rule, during repair work.

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Thermal insulation of pipes or 6 ways to avoid freezing in winter

July 28, 2016
Specialization: master of interior and exterior finishing (plaster, putty, tiles, drywall, lining, laminate, etc.). In addition, plumbing, heating, electrical, conventional cladding and balcony extensions. That is, the renovation of an apartment or house was done on a turnkey basis with all the necessary types of work.

Let me start with the fact that the thermal insulation of heating network pipelines
SNiP does not have any clear characteristics, and, perhaps, this is at least strange. However, this is not the point - I want to tell you how to insulate pipes and not freeze in winter in a private house. I will back up my words with visual video In this article. So, let's go...

Warming the pipes

Pipes can be heated not only with passive insulation, but also with active devices. But I will talk about this below.

6 types of insulation

Now we will briefly look at 5 types that SNiP allows for thermal insulation of equipment and pipelines:

1. The most proposed and advertised option that you can find on the Internet are shells that are made from mineral wool, polystyrene foam or extruded polystyrene foam.
2. Next in popularity is mineral (basalt) wool with waterproofing made of roofing felt or dense polyethylene.
3. In addition, thermal insulation of equipment and pipelines can be made with materials such as sand or expanded clay - the main thing is that such pads are dry.
4. Most best option for pipe insulation, this warm room- a basement, a room in an apartment, or just a closed box.
5. A heating cable that can be inserted directly into the pipe or wrapped around it from above - the effect will essentially be the same as in the case described in paragraph 4.
6. And finally, liquid insulation and paints that simply cut off cold air to the pipes. There can be many options here, but, in my opinion, it is best to use liquid foam - the price will suit you, and it’s easy to do.

Insulation material	Thermal conductivity (W/m⁰C)	Temperature for application (⁰C)	Flammability group
Stitched mineral mats	0,041-0,032	From -180⁰C to +450⁰C for fabric base and up to +700⁰C for metal mesh base	Non-flammable
Mats and wool made of thin basalt fiber without binding elements	0,031-0,24	From - 180⁰C to +600⁰C	Non-flammable
Extruded polystyrene foam materials	0,032	From - 180⁰C to +70⁰C	G3, G4
From foam polymer minerals	0,044	From - 180⁰C to +150⁰C	G2
Made from reinforced foam concrete	0,05	From - 180⁰C to +180⁰C	G2
Made from reinforced foam concrete	0,029-0,024	From - 180⁰C to +130⁰C	G2-G4
Made from foamed polyethylene	0,05	From - 70⁰C to +95⁰C	G3, G4

Various pre-insulated pipes for heating networks

My best option

Double insulation - polyethylene foam and mineral wool

So, this is not an instruction, but just my opinion, but, nevertheless, I have used this method for more than one year - mineral (basalt) wool. Let's start with the definition of mineral wool - it can be glass, slag or stone (basalt). The packing density directly depends on your efforts, and, in fact, it doesn’t really matter (unless, of course, you compress the cotton wool).

There are three types of mineral wool - glass, slag and stone or basalt. In our case, it is best to use the latter option - such products are made from melts of volcanic rocks.
It is very inconvenient to work with glass wool, but iron particles remain in the slag wool, which rust when exposed to dampness, which leads to subsidence of the material.

I usually use two options for thermal insulation of pipes - foamed polyethylene and mineral (basalt) wool. Of course, you can buy shells made of this material in the store, and even with a foil surface, but this will be quite expensive.

Much easier to use roll material, the thickness of which can be from 20 mm to 200 mm. You need to choose this parameter depending on your region of residence, that is, on a possible decrease in ground temperature in winter.

For underground pipe laying, of course, it is best to use the burial method rather than insulation. If the pipeline runs 50 cm below the freezing point, then you do not need any insulation.

But there may be a real problem here - northern regions In Russia, the depth of soil freezing sometimes reaches more than 2 m, so this option will not always be convenient.

As you understand, moisture will in any case be an excellent conductor of cold, therefore, without waterproofing, insulation of pipelines is only allowed indoors, as in the photo above. These could be basements, but even there, in some cases, it is impossible to do without waterproofing due to the same condensation.

Ruberoid is an excellent waterproofing

In order to insulate a pipeline with underground or overhead installation, I wrap it with basalt wool, trying not to compress the material too much. The looser the material, the better protection from the cold and warmer in winter.

To fix the material it is very convenient to use nylon thread - such a spool can probably be purchased in any store where they sell Construction Materials. But it is best to wrap roofing felt with any soft wire - the cheapest is steel knitting wire, but if you have supplies, it can be aluminum or even copper.

In addition, it is best to lay the underground pipeline with a sand cushion and also cover it with 50-60 mm of sand on top. This measure will protect the shell from sharp stones of various objects that may be in the ground - glass, wire, and so on.

Conclusion

In conclusion, I want to say that it is quite simple to insulate any pipeline (water supply, sewerage) with your own hands - the main thing is not to compress the material too much. When compressed, the density increases, therefore, the thermal conductivity also increases. If you have other suggestions on how to insulate the pipeline so as not to freeze in the cold, write about it in the comments.

July 28, 2016

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