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Technology of thermal insulation of external pipelines with mesh fastening. Constructive solutions for thermal insulation based on thermal insulation products made from fibrous materials for industrial pipelines and equipment. Thermal insulation of steel vertical

In the case when thermal insulation of pipes is carried out with half-cylinders made of hard materials (Sovelite, vulcanite, diatomite, etc.), they are installed dry or on mastic. Calc-silica, perlite-cement, foam diatomite, etc. segments are also used. The mats are laid with overlapping seams and secured at 500 mm intervals with wire hangers. The longitudinal seam is sewn with soft wire with a diameter of 0.8 mm. The outside of the mats is secured with bandages. The following materials are used during installation: bandage buckles ( , TU 36-1492-77), or buckles made of galvanized sheet steel 0.8 mm thick (GOST 7118-78). The material for making bandages is packaging or aluminum tape 0.8 mm thick. According to SNiP 2.04.14-88, the use of rings made of galvanized or black annealed wire with a diameter of 2 mm is allowed; as well as wire rings (diameter 1.2 mm) made of stainless steel.

The cost of a bandage buckle TYPE 1A according to TU 36.16.22-64-92 is 7.30 rubles/piece.
Basically, the protective covering is secured with screws or bands. For internal pipelines with a positive temperature of the substances transported through them, cylinders lined with aluminum foil are used. This insulation can be used without protective coating. As a bandage, it is recommended to use tape made of aluminum and aluminum alloys (width 20-30 mm, thickness 0.8 mm) and aluminum buckles. For a cold water supply pipeline (the temperature of the substances transported through it is below 12 degrees C), as well as process pipeline An exception is used as insulation. In this case, it is necessary to install a vapor barrier layer in accordance with the requirements of SNiP 2.04.14-88 “Thermal insulation of pipeline equipment.” The seams of the vapor barrier layer must be carefully sealed. Tears and punctures of the vapor barrier layer are not allowed. When using aluminum foil-laminated cylinders for installation, it is possible not to use a vapor barrier layer unless the project requires it. However, it is necessary to seal the seams and joints of the installed cylinders well. During installation, ruptures and punctures of aluminum foil are possible. If such damage is present, these places are sealed with sealing materials. Using cylinders,, for thermal insulation of cold water supply and process pipelines, with the temperature of transported substances below 12 ° C, it is recommended to install a protective layer under the metal protective coating to protect the foil from damage. In this case, it is recommended to secure the protective coating with bandages. When using cylinders on vertical sections of pipelines, unloading devices should be installed every 3-4 meters along the pipe height to prevent the thermal insulation layer and coating from slipping. For channel pipelines and tunnels, it is recommended to use it without subsequent installation of a protective coating. Thermal insulating cylinders made of mineral wool based on fiber from rocks are a highly effective environmentally friendly thermal insulation material that meets the requirements fire safety. Hydrophobization, fire safety and lower price, compared to imported materials from foam rubber and polystyrene, make the cylinders competitive for use in domestic practice as thermal insulation of cold water supply and process pipelines with negative temperatures. Cylinders, as form-stable products, they can be used in thermal insulation structures of horizontal pipelines without a device supporting structures. They can also be used as a heat-insulating material with the base of coupling and flange fittings of small diameters (valves, check valves) and flange connections. Laminated cylinders can be used in rooms and ducts (heating networks, water supply) without installing a covering layer. Also foil-laminated cylinders, it is possible to use without a vapor barrier layer in pipelines with negative temperatures. In this case, it is necessary to ensure sealing of seams and places where the foil is damaged. This insulation option significantly reduces the cost of structures and thermal insulation work. Thermal insulation of pipelines is necessary both to protect the pipelines themselves from the effects of external temperatures, and to avoid losses from the pipelines themselves. For example, cold water supply pipelines are thermally insulated from the effects of low outside temperatures. And steam pipelines, heating networks and hot water supply pipelines are insulated to reduce heat loss during external environment. Various materials are used for thermal insulation work, but the most popular is foiled mineral wool. However, when insulating high-temperature objects (for example, thermal insulation of a boiler), it is more effective to use basalt products. This material is the easiest to use. Also except correct selection material, it is necessary to clearly know for what specific purposes the thermal insulation will be used. The wrong choice of thermal insulation materials leads to frequent repairs pipelines, and sometimes even to emergency situations.

To also learn about the possibilities of thermal insulation of tanks, thermal insulation of boilers, thermal insulation of chimneys and more technological equipment, we recommend contacting our specialists by phone or E-mail.

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 time, since the probability of freezing and failure of pipes is quite high and also dangerous.

According to existing standards, as well as rules for safe operation steam supply pipes and hot water, 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 of the protective coating laid in a room, heat flux density standards are taken as a basis. IN 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. temperature difference environment 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. ability of an insulator to resist various kinds 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 constant operating temperature protective insulation.
• Insulation of communications of water heating networks of two-pipe underground channel gaskets.
• 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 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;
• pouring
• casing;
• combined.

By area of ​​use:

• for water drainage and sewerage;
• for steam, heating, hot and cold water;
• 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 execution. 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, the coolant of which is 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. Thermal insulation design similar type looks 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, minimum thickness, expanded polystyrene is excellent for protecting heating networks and water supplies.

• 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. Double layer construction allows you to both maintain the temperature of the networks and heat 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.

• 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 wrapper for a pipe of a certain diameter with a technological cut, which is put on required area systems.

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 above top part lines, 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 suctioning 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.

A perfect approach to the choice of thermal insulation can ultimately lead to minimum costs and reducing 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

Specialists with equal accuracy and 100% quality workmanship can perform work with various materials: galvanized steel, aluminum, stainless steel, as well as thermal insulation for pipes, thermal insulation cylinders, insulation in the form of mats and slabs. Pipeline thermal insulation work include surface preparation, priming, installation of vapor barrier, mineral material, fasteners, galvanizing (at the request of the client).

Carrying out installation of thermal insulation materials on pipes, industrial, main and routes with various working fluids, we offer additional installation of a thin-sheet metal casing. Its device will allow you to avoid mechanical damage to the internal heat-insulating layer and protect it from direct exposure to moisture. The completed installation of the galvanized shell makes the pipeline aesthetically attractive, convenient for maintenance and care.

Specify prices for thermal insulation of pipelines and you can get a preliminary estimate of the price by calling the indicated telephone numbers.

Why should you trust insulation installation professionals? Because when the right approach You can achieve an extension of the service life of the pipes themselves, eliminating ruptures, damage, and corrosion.

Insulation of buildings inside

When repairing the facade and insulating it is impossible, or the installed insulation does not bring the expected result, the only effective solution insulation of building walls is installation of reflective thermal insulation. Depending on the wall material, experts select suitable way fastening: with glue, stapler, nails, double-sided tape. All joints are treated with aluminized strips or tape. For finishing works The sheathing is made on top of the insulation. Installation of foil thermal insulation allows you to stop thermal radiation.

When choosing durable sheet insulation installation of thermal insulation materials is carried out on a pre-prepared profile, after which the slabs are glued to the walls.

Asters are used in their work only by those adhesive compositions, which are recommended by the thermal insulation manufacturer and have excellent adhesion.

To find out the preliminary cost of installing thermal insulation indoors, call a specialist.

Stages of work:

• You need to call our company to order installation services. At this stage, a master is called, the scope of work is clarified, and the final goals are determined.
• Thermal insulation is being designed. At this stage it is selected suitable look thermal insulation, methods of pipeline insulation(contractions, walls), the quantity is calculated, drawings, diagrams and other working documentation are made.
• The cost of work on insulating pipelines (walls, facades, technological equipment) is calculated, and an estimate for completing the order is provided, taking into account or excluding the purchased thermal insulation products.
• Thermal insulation is being installed. Our specialists implement projects in the shortest possible time.

To order installation of wall insulation, structures, pipelines, call us at the numbers provided.

Thermal insulation of pipelines is a set of measures aimed at preventing the heat exchange of the medium transported through them with the environment. Thermal insulation of pipelines is used not only in heating systems and hot water supply, but also where technology requires transportation of substances with a certain temperature, for example, refrigerants.

The meaning of thermal insulation is the use of means that provide thermal resistance to heat transfer of any kind: contact and carried out through infrared radiation.

The greatest application, expressed in numbers, is the thermal insulation of pipelines of heating networks. Unlike Europe, centralized system heating dominates throughout the post-Soviet space. In Russia alone, the total length of heating networks is more than 260 thousand kilometers.

Much less often, insulation for heating pipes is used in private households with autonomous system heating. Only in a few northern regions are private houses connected to the central heating main with heating pipes placed on the street.

For some types of boilers, for example, powerful gas or diesel boilers, the requirements of the set of rules SP 61.13330.2012 “Thermal insulation of equipment and pipelines” are required to be placed separately from the building - in a boiler room several meters away from the heated object. In their case, a fragment of the piping passing through the street necessarily needs insulation.

On the street, insulation of heating pipelines is required both when installed above ground and when laid hidden - underground. The latter method is a channel method - a reinforced concrete trench is first laid in the trench, and pipes are already placed in it. Channelless placement method - directly in the ground. Applicable insulation materials differ not only in thermal conductivity, but also in steam and water resistance, durability and installation methods.

The need to insulate cold water supply pipes is not so obvious. However, you cannot do without it when the water supply is laid open above ground - the pipes must be protected from freezing and subsequent damage. But inside buildings, water supply pipes also have to be insulated - to prevent moisture condensation on them.

Glass wool, mineral wool

Insulating materials proven by practice. Meet the requirements of SP 61.13330.2012, SNiP 41-03-2003 and fire safety standards for any installation method. They are fibers with a diameter of 3-15 microns, close to crystals in structure.

Glass wool is made from waste from glass production, mineral wool from silicon-containing slag and silicate waste from metallurgy. The differences in their properties are insignificant. Available in the form of rolls, stitched mats, plates and pressed cylinders.

It is important to be careful with materials and know how to handle them correctly. Any manipulations must be performed in protective overalls, gloves and a respirator.

Installation

The pipe is wrapped or lined with cotton wool, ensuring uniform filling density over the entire surface. Then the insulation, without too much pressure, is fixed using a knitting wire. The material is hygroscopic and easily gets wet, so insulation of external pipelines made of mineral or glass wool requires the installation of a vapor barrier layer made of a material with low vapor permeability: roofing felt or polyethylene film.

A covering layer is placed on top of it to prevent the penetration of precipitation - a casing made of roofing tin, galvanized iron or sheet aluminum.

Basalt (stone) wool

More dense than glass wool. The fibers are made from the melt of gabbro-basalt rocks. Absolutely non-flammable, can withstand temperatures up to 900° C for a short time. Not all insulating materials, like basalt wool, can be in long-term contact with surfaces heated to 700° C.

Thermal conductivity is comparable to polymers, ranging from 0.032 to 0.048 W/(m K). High performance indicators allow it to be used thermal insulation properties not only for pipelines, but also when installing hot chimneys.

Available in several versions:

• like glass wool, in rolls;
• in the form of mats (stitched rolls);
• in the form of cylindrical elements with one longitudinal slot;
• in the form of pressed fragments of a cylinder, the so-called shells.

The last two versions have various modifications, differing in density and presence heat reflective film. The cylinder slot and the edges of the shells can be made in the form of a tenon joint.

SP 61.13330.2012 contains instructions that the thermal insulation of pipelines must comply with safety and environmental protection requirements. Basalt wool itself fully complies with this instruction.

Manufacturers often resort to tricks: to improve consumer performance - to give it hydrophobicity, greater density, and vapor permeability, they use impregnations based on phenol-formaldehyde resins. Therefore, it cannot be called 100% safe for humans. Before use basalt wool In a residential area, it is advisable to study its hygiene certificate.

Installation

The insulation fibers are stronger than glass wool, so it is almost impossible for its particles to enter the body through the lungs or skin. However, it is still recommended to use gloves and a respirator when working.

Installation of rolled sheets is no different from the method of insulating heating pipes with glass wool.

Thermal protection in the form of shells and cylinders is attached to the pipes using mounting tape or a wide bandage. Despite some hydrophobicity of basalt wool, pipes insulated with it also require a waterproof, vapor-permeable shell made of polyethylene or roofing felt, and an additional one made of tin or dense aluminum foil.

Foamed polyurethane (polyurethane foam, PPU) Reduces heat loss by more than half compared to glass wool and mineral wool. Its advantages include:, excellent waterproofing properties. The service life declared by the manufacturers is 30 years; The operating temperature range is from -40 to +140 °C, the maximum withstandable for a short time is 150 °C.

The main brands of polyurethane foam belong to the flammability group G4 (highly flammable). When the composition is changed by adding fire retardants, they are assigned G3 (normally flammable).

Although polyurethane foam is excellent as an insulating material for heating pipes, keep in mind that SP 61.13330.2012 allows the use of such thermal insulation only in single-family houses residential buildings, and SP 2.13130.2012 limits their height to two floors.

Thermal insulation coating is produced in the form of shells - semicircular segments with tongue and groove locks at the ends. Ready-made ones are also available for sale. steel pipes in isolation from polyurethane foam with a protective sheath made of polyethylene.

Installation

The shells are secured to the heating pipe using ties, clamps, plastic or metal bandage. Like many polymers, the material does not tolerate prolonged exposure sunlight, therefore, an open above-ground pipeline when using polyurethane foam shells requires a covering layer, for example, made of galvanized steel.

For underground ductless placement, thermal insulation products are laid on waterproof and temperature-resistant mastics or adhesives, and the outside is insulated with a waterproof coating. It is also necessary to take care of anti-corrosion surface treatment metal pipes – even glued lock connection

The shells are not dense enough to prevent water vapor from condensing from the air.

Expanded polystyrene (foam plastic, EPS)

It is produced in the form of shells, practically no different in appearance from polyurethane foam - the same dimensions, the same tongue-and-groove locking connection. But the application temperature range, from -100 to +80 °C, with all this external similarity, makes its use for thermal insulation of heating pipelines impossible or limited. SNiP 41-01-2003 “Heating, ventilation and air conditioning” states that in the case of two-pipe system

heating supply, the maximum supply temperature can reach 95°C. As for the return heating risers, not everything is so simple: it is believed that the temperature in them does not exceed 50 °C. Foam insulation is more often used for cold water and sewer pipes. However, it can be used on top of other insulation materials with a higher permissible temperature

The material has a number of disadvantages: it is highly flammable (even with the addition of fire retardants), does not tolerate chemical influences (dissolves in acetone), and crumbles into balls during prolonged exposure to solar radiation.

There are other non-polystyrene foams - formaldehyde, or phenolic for short. In fact, it is a completely different material. It is devoid of these disadvantages and is successfully used as thermal insulation for pipelines, but is not so widespread.

Installation

The shells are secured to the pipe using a bandage or foil tape; they can be glued to the pipe and to each other.

Foamed polyethylene

Temperature range at which the use of foamed polyethylene is allowed high pressure, from -70 to +70 °C. The upper limit is not compatible with the maximum temperature of the heating pipe, usually accepted in calculations. This means that the material is of little use as thermal insulation for pipelines, but can be used as an insulating layer over a heat-resistant one.

Polyethylene foam insulation has found virtually no alternative use as protection against freezing of water pipes.

Very often it is used as a vapor barrier and waterproofing. The material is produced in the form of sheets or in the form of a flexible thick-walled pipe. The latter form is more often used, as it is more convenient for insulating water pipes. Standard length

- 2 meters. Color varies from white to dark gray. There may be a coating of aluminum foil that reflects IR radiation. The differences relate to internal diameters (from 15 to 114 mm), wall thickness (from 6 to 30 mm).

Installation

The application ensures the temperature on the pipe is above the dew point, which means it prevents the formation of condensation.

A simple way with worse vapor barrier results is to cut the foam material along a small depression along the side surface, open the edges and put it on the pipe. Then wrap it along the entire length with mounting tape. More difficult decision (and not always feasible) - turn off the water, completely dismantle the insulated sections of the water supply system and put on whole sections. Then put everything back together. Secure the polyethylene with ties. In this case vulnerable spot

there will only be a junction of segments. It can be glued or also wrapped with tape.

Foam rubber Foamed synthetic rubber with a closed-porous structure - the most universal material

Used as insulation of cold water pipelines, insulation of heating pipes, often found in refrigeration systems and ventilation systems.

Heating pipes laid inside buildings and insulated with rubber do not require the installation of a vapor barrier layer.

Externally similar to foamed polyethylene, it is also available in the form of sheets and flexible thick-walled pipes. Installation is also practically no different, except that such thermal insulation of pipes can be attached with glue.

Liquid insulation A technology has been successfully used that allows you to independently spray foam from a polyurethane composition onto already ready-made designs . Excellent adhesive properties

allow it to be used not only to insulate pipelines, but also to be applied to other elements that require insulation: foundations, walls, roofs. The coating, in addition to thermal protection, provides hydro, vapor barrier, and provides anti-corrosion resistance.

Conclusion

Proper installation of thermal insulation is a guarantee that the pipe will not lose heat and the consumer will not freeze. Freezing of a cold water supply pipeline invariably leads to its rupture. Until recently, glass wool was the usual insulating material for hidden and open heating mains. Its shortcomings stem from one another. This coating requires constant monitoring.

Even with slight damage to the protective surface layer, vapor permeability and hygroscopicity reduce all savings to nothing. Moisture causes low thermal resistance and premature failure. Modern insulating materials with a cellular structure, inert to the effects of steam and water: polyurethane foam, foam rubber, polyethylene foam will help to significantly improve the situation.

Installation work

Technical requirements

SNiP 3.04.01-87 pp. 2.32, 2.34, 2.35, table. 7

Permissible deviations:

When installing thermal insulation from rigid products laid dry, it is necessary to ensure:

The gap between the products and the insulated surface is no more than 2 mm;

The width of the seams between products is no more than 2 mm;

Fastening of products - according to the project.

When installing thermal insulation using soft and semi-rigid fibrous products, it is necessary to ensure:

Compaction factor:

for semi-rigid products - no more than 1.2; for soft ones - no more than 1.5;

Tight fit of products to the insulated surface and to each other;

Overlapping longitudinal and transverse seams with insulation in several layers;

Installation of fastenings on horizontal pipelines to prevent sagging thermal insulation.

When constructing thermal insulation cover shells, it is necessary to ensure:

Tight fit of shells to thermal insulation;

Reliable fastening using fasteners;

Thorough sealing of flexible casing joints.

When installing an anti-corrosion coating on metal pipes, it is necessary to check the continuity, adhesion to the protected surface, and thickness.

Not allowed:

Mechanical damage;

Sagging layers;

Loose fit to the base.

Requirements for the quality of materials used

GOST 10296-79*. Isol. Technical conditions.

GOST 23307-78*. Heat-insulating mats made of mineral wool, vertically layered. Technical conditions.

GOST 16381-77*. Heat-insulating construction materials and products. Classification and general technical requirements.

GOST 23208-83. Heat-insulating cylinders and half-cylinders made of mineral wool with a synthetic binder.

Isol must be flexible. When bending a strip of I-BD grade Isol at a temperature of minus 15 “C, I-PD grade at a temperature of minus 20 “C on a rod with a diameter of 10 mm, no cracks should appear on the I-BD strip. Isol must be temperature resistant. When heated in a vertical position for 2 hours at a temperature of 150 ° C, there should be no increase in length or the appearance of swelling. The insulating material must be wound on a rigid core with a diameter of at least 60 mm, made of a material that ensures the safety of the insulating material during transportation and storage. The length of the core should be equal to the width of the web or less than 10 mm. The ends of the insulation roll, as well as the edges of the sheets at the joint of the roll, must be trimmed evenly. The insulating material should not have holes, tears, folds, edge tears, as well as unprocessed rubber particles and foreign inclusions. The lower surface of the insulating material (inner V roll) must be covered with a continuous layer of dusty coating. The insulating material should not be sticky.

Thermal insulation materials and products must meet the following general technical requirements:

Have a thermal conductivity of no more than 0.175 W/(m K) at 25 °C;

Have a density ( volumetric mass) no more than 600 kg/m 3 ;

Possess stable physical, mechanical and thermal properties;

Do not release toxic substances and dust in quantities exceeding the maximum permissible concentrations.

For thermal insulation of equipment and pipelines with an insulated surface temperature above 100 °C, inorganic materials must be used.

Foam diatomite and diatomite thermal insulation products must have the correct geometric shape. Permissible deviations from the perpendicularity of edges and edges should not exceed 3 mm. Defects in appearance are not allowed in products:

Voids and inclusions more than 10 mm wide and deep;

Broken and blunted corners and ribs more than 12 mm deep And
longer than 25 mm;

Through cracks over 30 mm long; products with cracks above
30 mm is considered halfway.

Instructions for carrying out work

SNiP 3.04.01-87 pp. 1.3, 2.1, 2.8-2.9, 2.32, 2.33,

SNiP 3.05.03-85 pp. 6.1, 6.2

Thermal insulation work can begin only after the execution of an act (permit) signed by the customer and representatives of the installation organization and the organization performing thermal insulation work.

Insulation work can be carried out at positive temperatures (up to 60 °C) and negative temperatures (up to -30 °C).

Before insulation, the surfaces of pipelines must be cleaned of rust, and those subject to anti-corrosion protection must be treated in accordance with the requirements of the project. Thermal insulation work on pipelines should begin only after they are permanently secured. Insulation of pipelines located in non-passable channels and trays must be performed before they are laid.

At coolant temperatures up to 140 °C for protection outer surface pipes of heating networks against corrosion, a coating of Isol is used in two layers on Isol mastic. The total thickness of the coating is 5-6 mm. For air heating networks with a coolant temperature of up to 140 °C, coatings combined with BT-177 paint and GF-020 primer are used to protect the pipe surface from corrosion. The total coating thickness is 0.15-0.20 mm.

To check the quality of work on the anti-corrosion protection sticker, an incision is made to the metal in an area measuring 200 x 200 x 200. The quality is considered satisfactory if the insulation is separated from the pipe with some force. 5% of pipes are subjected to this pull-out test.

Thermal insulation on pipelines should be secured with bandages. To protect the main layer of thermal insulation from moisture and mechanical damage, it is necessary to use cover shells made of rigid or flexible (non-metallic) materials.

Installation of thermal insulation products must begin from flange connections and fittings and be carried out in the direction opposite to the slope.

During an intermediate check, surfaces prepared for thermal insulation are inspected; with multi-layer thermal insulation, each layer is checked before applying the next one. During the final check of thermal insulation, the uniformity of the insulation thickness along the entire length of the forward and return pipelines is determined.

The thickness of the insulation is checked with a probe. Particular care must be taken to monitor the dosage of cement and asbestos when protecting insulation with asbestos-cement mortar. Excess cement in the asbestos cement mass leads to cracking after hardening and heating.