Asbestos-cement pipes have found their application in many areas: the construction of residential buildings and industrial structures, as well as the construction of communications. The popularity of this material is due to the fact that the product is quite durable. Asbestos-cement pipes are made from a mixture of Portland cement and asbestos admixtures. Manufactured pipelines differ in parameters such as diameter, length and other characteristics.

Asbestos cement pipe: what is it?

Asbestos pipes are made from two main components, which are Portland cement and asbestos fiber. Water is used to obtain a uniform consistency. The use of these materials makes it possible to obtain a material that is light in weight and has a low thermal conductivity. Asbestos cement is cement mortar, which is reinforced with asbestos fiber. Asbestos undergoes a grinding process to a powdery consistency, after which it is separated into fibers. It is these fibers that are the connecting link in the concrete mixture.

Strength asbestos pipes obtained by reinforcing concrete with asbestos fiber. This allows you to increase strength by 40% compared to conventional concrete devices.

A significant advantage of asbestos is its low thermal conductivity. It is due to their low thermal conductivity that asbestos pipes are used for the construction of sewer pipelines with high freezing rates. A significant advantage of asbestos pipes is the absence of electrocorrosion properties. If the service life of metal pipelines, in which the phenomenon of stray currents is observed, is reduced to 4-5 years, then asbestos pipes, with such a negative influence, can last tens of times longer.

When choosing asbestos pipes, it is important to take into account such parameters as the diameter and length of the products. The products under consideration are of two types: pressure or non-pressure. Below is a table with technical parameters for pressure and non-pressure asbestos pipes.

What are the products in question?

In the Russian Federation, asbestos-cement pipes with a length of 3.9 to 5 meters are manufactured. Dimensions asbestos-cement products the following:

• 100 mm;
• 150 mm;
• 200 mm;
• 250-500 mm.

The diameter of the pipes is an important parameter, therefore, depending on its size, pipes are used for various purposes. The strength of the products under consideration is influenced by such an important parameter as the thickness of the pipe walls. To connect asbestos-cement materials into the main line, special connectors made of a similar material or PVC are used.

Asbestos is a non-toxic substance that does not emit toxins or radiation. The only major danger is asbestos dust, which is formed when sawing pipes.

To avoid dust entering the body, work must be performed exclusively in respirators or masks.

Types of pipelines

Asbestos-cement types of pipes are used where it is impossible to use metal. Metal is not used where available high humidity, therefore non-pressure options are taken into account.

The considered version of the products has a bending strength of 30 MPa. The compressive strength is equal to 90 MPa. These are quite significant figures, especially considering that the material has a low density.

Asbestos pipes can withstand 60 defrost cycles, which allows us to judge long term services.

The material in question comes in two types: non-pressure and pressure, as discussed above. Let's look at the difference between an asbestos-cement non-pressure pipe and a pressure pipe.

1. Non-pressure types of asbestos-cement pipes are used exclusively where there is no pressure. These application systems include: chimney, ventilation, sewerage. Non-pressure or gravity-flow products are used in construction, from which foundations and fences are constructed. This type of pipeline is used to construct underground channels for laying communications.
2. Asbestos-cement options for pressure pipes are used where materials under pressure are transported through products. The medium of these materials can be presented not only in the form of liquid, but also gas. Pressure versions of the product are used for installation of water supply systems, gas supply and irrigation systems.

The differences between pressure and non-pressure pipes lie in their sizes. These dimensions are: wall thickness and pipeline diameters. In a free-flow pipeline, the wall thickness ranges from 7 to 18 mm. In pressure products, the wall thickness ranges from 9 to 43.5 mm. The internal diameter of the first option reaches values ​​from 50 to 500 mm, and of the second type of pipes up to 600 mm. Pressure products can withstand pressure from 3 to 12 atmospheres.

To combine asbestos-cement products of pressure and non-pressure types, they are used different kinds couplings For non-pressure products, ordinary asbestos rings are used, and for pressure products, rings with rubber seals are used.

Advantages

In comparison with other pipeline options, the products in question have a number of various benefits. These products are easy to install and have high reliability and strength. They are highly resistant to both aggressive environments and moisture. If we compare products with metal counterparts, the latter option has a much shorter service life.

Metal products require replacement or repair after 5-10 years. Moreover metal pipes susceptible negative impact not only from the outside, but also from the inside. Corrosion causes a narrowing of the internal diameter, which results in a decrease in pressure. Even when carrying out repairs that involve purging metal devices, the problem cannot be solved. This is explained by the fact that rust does not disappear on the walls and continues to destroy the material.

If water is supplied through asbestos pipes, the material only gets stronger over time. This is explained by the compaction of the walls due to the hydration of the cement mixture.

Some of the main advantages of asbestos-cement products include the following factors:

1. The material does not require waterproofing.
2. Resistance to temperature fluctuations.
3. There is no electrical conductivity.
4. High resistance to aggressive environments and moisture.
5. No condensation occurs during supply cold water through pipes.
6. Fire safety.
7. Possibility of transporting liquid through pipes with a maximum pressure of up to 12 atmospheres.
8. The average service life is 30-35 years.

Studies that were carried out in Germany, Switzerland and the USA confirmed the fact that asbestos is a safe substance among its analogues. Once it enters the body, rapid elimination occurs.

Flaws

Like any material, asbestos-cement pipes have some disadvantages. It is important to note them in order to determine the need to use them for certain purposes. The main disadvantage of the materials under consideration is fragility. During transportation or installation, any mechanical impact can lead to damage to the integrity of the product.

Asbestos-cement pipes cannot withstand heavy weight, which leads to damage to sewer lines and pipelines. When installing chimneys made of asbestos, there is a violation of the integrity of the products, and when exposed to high temperatures, such materials may explode. The products also do not have sufficient heat capacity, so they are not able to maintain the necessary traction. Soot settles on the inner walls of the pipes, which over time helps to reduce the diameter, which means bandwidth and traction.

Production Features

The manufacturing process of the products in question involves performing the following manipulations in production:

1. Initially, asbestos must be crushed.
2. 85% cement and water are added to 15% asbestos.
3. The prepared mixture is poured into a special drum in the form of a mesh, in which the solution takes the shape of a pipe.
4. After squeezing, a film is formed, the thickness of which does not exceed 0.2 mm. The width of this film is equal to the future length of the product.
5. The film is wound onto the drum, resulting in the formation of a product.

The result is a pipe of a certain size and appropriate diameter, which is ready for use.

Installation features

Pipe laying is carried out according to certain requirements. These requirements include the following factors:

1. Pipes with an internal diameter exceeding 150 mm require additional processing. It is required in order to obtain the appropriate dimensions and roughness.
2. The products are connected using special couplings. These couplings are equipped with grooves as well as corresponding rubber sealing rings. For a certain pipe size, appropriate couplings are used. This type of connection design allows for a high-quality fit of the pipe to the coupling, which is important in the presence of internal pressure in the pipeline.
3. A radial gap is left at the junction of the products. Such a gap is required in order to ensure deflection of the pipeline when the seal fails.
4. Installation of pipes with diameters of more than 150 mm is carried out directly with indentations. This is done for the purpose of eliminating the need to install additional linear compensators.

When asbestos pipes are heated to temperatures above 100 degrees, the walls increase (asbestos modification) by 0.4 mm. To avoid failure of the rubber seal, it is deformed by the end parts by 0.2 mm.

When installing asbestos-cement pipes, the need for welding work is eliminated. This makes the job easier and also speeds up the installation process.

Requirements for the production of asbestos-cement pipes

There are some requirements for the production of asbestos-cement pipes. Manufactured products must meet the following state standards:

1. The diameters of the pipelines must comply with the requirements in accordance with GOST 539-80.
2. After manufacturing the materials in question, they must be tested in accordance with GOST 11310-90.

During the Soviet Union, the products in question were used for the construction of reclamation canals. In those days, the use of such products for the construction of civil and industrial construction projects was not envisaged. The reason for this was a worldwide ban due to the harmfulness of asbestos. They became popular after the collapse of the Soviet Union, as chrysotile asbestos, which is harmless, began to be used for the manufacture of products. It was after this that appropriate standards were developed for the production of asbestos pipes for any needs.

In Simferopol, during the Soviet Union, an asbestos-cement highway was built, the length of which is 20 km. To construct this structure, pipes with a diameter of 700 mm were used. Today, products of this diameter are not produced.

Features of cutting products yourself

During the installation of asbestos cement pipelines, the need arises not only for connecting products, but also for cutting them. To perform this procedure, you will need to use a grinder and a diamond-coated disk.

Initially, you need to mark the place where the cutting will be done. To do this, use a tape measure, as well as chalk or a pencil. After the product has been marked (preferably along the entire outer diameter), it should be securely fixed. It is impossible to use a vice or similar devices for such purposes, as the integrity of the product will be compromised. At home, you can fix the product using two bricks or bars of the appropriate size.

After this, be sure to wear a mask or respirator to prevent inhalation of asbestos dust. A tool with any disk is suitable for cutting products of various diameters. After all, cutting will be performed sequentially along the marking line. The video below shows the process of how to properly cut asbestos products at home.

Another important point, as the possibility of connecting asbestos products using plastic couplings. Such couplings are used for products with a diameter of up to 150 mm. Connection using PVC couplings is made by heating the coupling construction hairdryer. Instead of a hair dryer, a tank with hot water, into which the clutch is lowered for 10 minutes. After this, the coupling is put on one end of the pipe, and then on the other until it stops.

Asbestos-cement products are popular. With their help, the process of constructing sewer lines is simplified not only for drainage, but also for laying communications.

Asbestos pipes, or asbestos-cement pipes, as they are also called, have always been considered a reliable and, most importantly, economical product, widely used in rural areas, in holiday villages for chimney pipes. In addition, products made from this material are widely used in construction: for example, sewer communications and the most famous - slate. But it’s no secret that slate bursts during a fire, however, this does not stop craftsmen from using asbestos pipes for chimneys. Meanwhile, this aspect is regulated by a number of regulatory documents.

Rules about fire safety It is strictly forbidden to use such material for construction. While building regulations allow the use of asbestos, provided that the temperature of the incoming gases is no more than 300 degrees Celsius. At the same time, when passing through attic space, asbestos pipes must be insulated to prevent condensation.

And although in the technical characteristics of asbestos-cement products, manufacturers indicate the possibility of their use for ventilation openings, chimneys and gas ducts, air ducts, the use of this material, in the presence of a furnace, can easily lead to very disastrous results. Please note that any attempt to make a chimney from this material on a coal stove will lead to a fire hazard, in simple terms, to a fire.

When used, it reveals all the disadvantages of this material, or more precisely, their unsuitability for use where there is a possibility of very high temperatures.

Firstly, the use of asbestos-cement material greatly reduces draft, since there is not enough heat capacity to support it, condensate is absorbed, and only vertical installation of the gas outlet is possible.

Secondly, there is no possibility to build special hatches for inspection and cleaning of soot from the chimney, which, you see, is important when using the stove for a long time. During the design, it was calculated that asbestos pipes would be used for low-power devices - geysers And gas heating with low temperature conditions.

To summarize the above, we can conclude: the use of this material is not intended for smoke exhaust systems stove heating, and sooner or later will lead to. Alternatively, it could be a burst pipe, and, as a result, exit through the resulting crack. Adjacent flammable material may ignite.

Today the construction industry can offer consumers enough safe materials, which allow residents of private houses not to play “Russian roulette”, but instead to create absolutely safe and regulated conditions for using heating systems.

Therefore, before you buy asbestos pipes and use them for chimneys, think 100 times whether it is worth doing this.

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Asbestos cement product: application and installation

On the materials market today you can find both new products in the industry and traditional products, time-tested. A classic of the genre in construction and repair - asbestos-cement pipes; a product that has been used by professionals for quite some time. This material can be found in external pipeline networks, in stove chimneys, and in the construction of fireplaces; it is also indispensable in creating irrigation and ventilation systems, in the construction of wells.

Asbestos-cement pipes, despite their low cost, are among the most durable and durable to use.

Asbestos cement is based on dispersed reinforced concrete; asbestos in in this case just a reinforcement that allows you to evenly distribute the composition throughout the product.

In total, the product contains about 85% cement and 15% asbestos.

I would like to note that it does not harm human health at all, since chemical composition— in a bound state, this, by the way, eliminates dusting during operation. Nowadays, products used in Russia are mainly from domestic manufacturers. Pressure and non-pressure asbestos pipes are available for sale:

Pressure pipes are designed for use in conditions of high (6-9 atmospheres) pressure.

1. Pressure ones are produced in accordance with GOST 539-80. They are designed for use in conditions of high (6-9 atmospheres) pressure. Scope of application: pressure networks of heating mains, water supply systems, sewerage systems, as well as drainage collectors and ventilation systems.
2. Non-pressure asbestos pipe must comply with GOST 1839-80. The product is used in the construction of non-pressure pipelines, gas supply, and ventilation construction. In addition, it can be found at the base of garbage chutes, protective covers and supports in fences.

Asbestos-cement products have many advantages:

1. Long service life. Asbestos-cement pipes “live” for 40 years or more.
2. Easy to install.
3. Ease of processing.
4. Not subject to corrosion.
5. Resistant to aggressive environments.
6. They are light in weight (compared to metal pipes)
7. High thermal insulation performance.
8. They have a smooth inner surface, which reduces the likelihood of blockages
9. There is no need to take measures to protect the asbestos pipe from groundwater (this is for external pipelines).
10. Affordable price. They are cheaper than plastic ones metal products.

Free-flow asbestos cement pipe

This product has been in use for almost a century; the product was first used in 1920. Let's list technical requirements, which a free-flow asbestos pipe must comply with:

Non-pressure asbestos-cement pipes are used in the construction of non-pressure pipelines, gas supply, and ventilation construction.

1. Its couplings must comply with the standard (GOST 1839-80).
2. Pipes must be exclusively cylindrical in shape.
3. The product must be straight, without any defects (delaminations, chips and cracks are not acceptable).
4. On the outer surface, a non-pressure asbestos pipe may have abrasions and imprints of cloth packaging up to 0.2 cm in depth.

Let us list once again where a free-flow asbestos-cement pipe can be found (we will add to the list):

1. In irrigation systems.
2. In the construction of vaulted foundations, 10-20 cm BNT is used in this case. Asbestos pipes are reinforced and then filled with concrete solution.
3. In pile foundations. The ideal product is 15-50 cm. The diameter depends on building materials used to build walls.
4. In channels for laying communication cables.
5. In chimneys. An asbestos pipe is suitable for this purpose if the temperature of the gases does not exceed 3000 degrees.
6. In landscaping elements. You can often see these products at the base of columns (the inside is filled with concrete), flowerpots, flower beds, pillars, and fences.
7. Sawed BNT 100 is suitable for the construction of gutters.

Non-pressure design: we install asbestos pipes

Whatever system is being built, you can connect the product in two ways. For this you will need:

1. Polyethylene couplings. It is recommended to use this option when installing the pipeline in dry soil. The method of application is as follows: the couplings are heated (this can be done, for example, by placing them in boiling water), then inserted into the pipe (all the way to internal partition); a second pipe is put on the opposite side.
2. Asbestos-cement couplings. The couplings are drilled (hole diameter - 2 cm), there should be two holes in each (on the same line). Two free-flow asbestos-cement pipes are laid side by side so that a tight joint is formed, and the prepared coupling is put on it. The gap can be filled with hemp winding, and molten bitumen can be poured into the holes.

Asbestos-cement pressure pipes

The asbestos pipe can withstand gas temperatures of 3000 degrees, so it is suitable for equipping a chimney.

As you already understand, gravity products should be used exclusively for pipelines that do not contain high blood pressure; for other cases there are pressure asbestos-cement pipes. We list the technical requirements for the product:

1. High-quality products have strictly perpendicular cut ends with a cone shape (their bevel angle is approximately 20 degrees). If the diameter of the pipe is 10-15 cm, then the length of the cone is approximately 1 cm.
2. All products must be pressure tested, after which there should be no water leaks on the external surface.
3. Asbestos-cement pressure pipes are usually supplied complete with other components (there should definitely be couplings there).

Installation of asbestos pipe

To connect the elements, asbestos-cement couplings are used; they usually come with rubber sealing rings. To make work easier, it is recommended to lubricate all parts with a graphite-glycerin composition. The coupling is put on the pipe before it is lowered into the trench. The second asbestos pipe is sent to its destination without couplings, and the third - with them (and so on). A tensioning device is used for installation.

A columnar foundation is perfect for buildings with frequently flooded areas.

The foundation is the basis of any building; it is the strength of this element that affects the operation of the building; Naturally, you cannot save on these works. One of the most affordable options today is a columnar foundation. To construct the system, you can use an asbestos-cement pipe or metal parts; we immediately note that the first option is preferable (the advantages of the composition are described above). Columnar foundations are most often used in the construction of light buildings, wooden houses, frame buildings, verandas, baths.

The construction principle is as follows: concrete mortar it is not poured over the entire area of ​​the building, but only in certain places (they will provide reliable support for the structure). Externally, the structure looks like this: pillars installed at a certain pitch in several rows. The number of pillars depends on the type of building; most often they are installed at the corners of the building, in the center and throughout the entire area of ​​the building. Their number should distribute the load evenly across all elements. The standard for our Russian soils is one column per two meters (both in width and length) of the building, the height of the parts is 30 cm (the value can be increased if your site is located in an area where there is a threat of flooding).

Preparing the site for an asbestos pipe foundation

Before you start building the foundation, prepare the site. This is done as follows:

1. You can start building a foundation from an asbestos-cement pipe only if you have in hand finished project Houses.
2. On the site, mark the places where the pillars will be installed. Place metal rods at these points.
3. Step back two meters on each side of the base boundary and mark this extended area.
4. Remove fertile soil from the marked area; in order to completely eliminate the germination of vegetation under the house, it is enough to remove 30 cm.
5. Carefully level the area prepared for the asbestos pipe foundation, and then fill it with sand (although gravel will also work).

Constructing a columnar foundation with your own hands from an asbestos pipe: stages of work

First, I would like to note that the type of building affects the required diameter of your elements:

1. If you are building a one-story wooden house without an attic, then use pipes with a diameter of 20 cm.
2. For heavy buildings, an asbestos pipe is suitable, the diameter of which is much larger (at least 25 cm).

The foundation itself from an asbestos pipe is made like this:

1. First make pits. To do this, you will need a garden drill; the diameter of the holes should be 10 cm larger than the pipe.
2. Place a layer of sand at the bottom of the pit and compact it well.
3. Install an asbestos pipe into the prepared hole and pour a 30 cm layer of sand around it.
4. Drive reinforcement around the element to a depth of 20 cm. By the way, the length of the rods should be 20% greater than the length of the pipes. The distance between adjacent rods is 7 cm.
5. Pour concrete into and around the center of the asbestos cement pipe. Constantly check the evenness of the pipes using a level.
6. Wait a while until the concrete hardens, do not carry out any other work.
7. After about two weeks, the concrete will gain sufficient strength, and you can begin erecting supports for the building on poles.

The use of asbestos pipes, as you can see, is quite wide; and this is not surprising, because this product has a huge list of advantages. Nowadays, the material is made from a safe type of asbestos, we are talking about chrysotile. Elements are usually produced in several configurations: the pipe diameter can be 100, 150, 200 and 500 mm.

Pressure and non-pressure asbestos-cement pipes are used in the construction of pipelines for domestic and industrial purposes. Long period of operation, relatively low cost of products and resistance to changes temperature regime- this is only a small part of the advantages of pipes made from this material. For the construction of which pipelines can this or that type of pipe be used? How to choose them and install them yourself? Answers to these and many other questions can be found in this article.

Pipe application area

Asbestos cement pipes are available in two types:

• pressure;
• non-pressure.

Application of pressure pipes

Asbestos-cement pressure pipes are produced in accordance with GOST 539-80 as follows:

1. Depending on the ability to withstand a certain pressure, they are divided into 4 types:

1. The shape of the pipe must correspond to the following:

1. Available in diameters from 50 to 500 mm. The dimensions of asbestos pressure pipes are presented in the table.

1. must be supplied by the manufacturer with rubber O-rings and couplings;
2. Before going on sale, they are subject to inspection and testing, during which parameters such as straightness, absence of defects, and the ability to withstand the declared loads are determined.

Pressure asbestos pipes are used for construction:

• pressure pipelines carrying water, gas, oil products, and so on;
• pressure sewer;
• chimneys;
• heating mains

Pipes cannot be used in systems in which the pressure exceeds the standards stated by the manufacturer.

Application of gravity pipes

Non-pressure asbestos-cement pipes are produced in accordance with GOST 1839 80 in the same way:

1. the shape of free-flow pipes is somewhat different from the shape of pressure pipes, since there is no special recess on the pipe for couplings;
2. The dimensions of produced BNT are in the range of 100 – 400 mm and must meet the following parameters:

1. All manufactured pipes must be tested for strength, absence of cracks and other defects, and water resistance.

Non-pressure asbestos-cement pipes are used for construction:

• gravity;
• inspection wells;
• storm sewer network;
• drainage system;
• chimney;
• garbage chute;
• foundation.

Gravity pipes can be used as protection when laying electrical cables or telephone lines, since the pipe material is not subject to electromechanical corrosion.

Selection rules

• type of pipes Can not use gravity pipes for the construction of water pipelines and other systems in which liquid or gas passes under pressure. Excessive pressure affects durability and can significantly reduce the service life;
• pipe diameter For each type of pipeline, the most optimal value parameter. You can also calculate the diameter using specialists or various online programs;
• wall thickness. This parameter affects the durability of use. If you plan to lay an external pipeline, then it is necessary to purchase pipes with a greater thickness, since there is a greater load.

Installation methods

When installing asbestos cement pipes you need to know:

• rules for preparing for connection;
• connection methods;
• rules for laying external pipelines.

Preparing for connection

Before connecting, asbestos pipes are prepared:

• cut according to the dimensions specified by the project. Cutting is done using a regular hacksaw, jigsaw or grinder;

• the ends of the products are cleaned as much as possible from contaminants, and if necessary, the chamfer is removed;
• If you need to insert a tee or any other fitting into the pipeline, then a hole of the appropriate diameter is drilled in the pipe.

How to properly cut a pipe, watch the video.

Connection of asbestos pipes

The connection is made using special couplings, which are equipped with O-rings.

Couplings can be manufactured:

• from asbestos;
• made of cast iron;
• made of plastic.

The dimensions of the couplings are selected in accordance with the outer diameter of the pipe; for example, to connect pipes with a diameter of 300 mm, a coupling with a similar diameter will be required. Permissible deviations from dimensions are +1.5 or -1.0.

The coupling must also be selected in accordance with the type of pipes, that is, non-pressure pipes are connected with gravity couplings, and pressure pipes with pressure couplings.

The connection with couplings is made according to the following scheme:

1. the surface of the pipe on which the coupling will be placed is treated with a graphite-based lubricant. This will simplify the connection process as much as possible;
2. a coupling is put on the first pipe;
3. the pipe is lowered into the trench to a permanent place;
4. the second pipe is lowered and approaches the connection point at a minimum distance;
5. the alignment of the products is checked and the second pipe and coupling are joined;
6. if necessary, the space between the pipes and the edges of the coupling is filled with mastic or other sealant.

Laying rules

Asbestos-cement pipes are laid in a specially prepared trench, equipped according to the following rules:

• the depth is determined in accordance with the climatic characteristics of the area.

Asbestos-cement elements do not tolerate freezing well, so the depth of the trench should be greater than the freezing depth of the soil.

• the bottom of the trench should be as level as possible. In exceptional cases, for example, with large differences in slope, installation on supporting wooden pads is possible;
• pipes laid in a trench must touch the ground with at least 1/4 of the surface. This will avoid deformation when high blood pressure and will significantly extend the life of the pipeline;

• The trench is backfilled only after testing the finished pipeline.

Properly selected and installed asbestos-cement pipes can last more than 50 years.

Asbestos-cement pipes are widely used in the construction of residential and non-residential structures, roads and communications for various purposes. The production of these products involves mixing cement, asbestos and water, resulting in the material having increased strength along its entire length.

Asbestos fiber, part of which is approximately 20%, plays the role of reinforcement. In the manufacture of the pipeline, the safest type of asbestos material is used - chrysotile. Over time, metal succumbs to rot and corrosion, reacts with an aggressive environment, and asbestos cement is noticeably superior to it in all respects.

The main advantages of asbestos-cement pipes

In addition to strength, asbestos-cement pipes have advantages that distinguish them from metal products. Key options include:

• Resistance to negative temperatures;
• Long service life;
• No sludge settling;
• Low hydraulic resistance;
• Corrosion resistance;
• Chemical inertness;
• Heat resistance;
• Possibility of installation in the ground (closed method);
• Affordable price;
• Light weight;
• Convenient connection using a special coupling;
• They have a variety of sizes.

Types of asbestos pipeline

Asbestos-cement pipes are used for the construction of free-flow and pressure sewers, water supply systems, drainage collectors and in land reclamation.

It is also possible to use these products in the construction of chimneys. There are two types of asbestos lines, which have different sizes, costs, diameters and purposes. Thus there are:

• Pressure asbestos-cement pipes;
• Non-pressure asbestos-cement pipes.

The production of asbestos products is regulated by GOST 539-80, GOST 1839-80 and GOST 11310-90.

The production of pressure pipes is carried out with the obligatory implementation of recommendations in accordance with GOST 539-80. Thus, the international standard stipulates that the diameter of products is 100 - 500 mm, and the length is 3.95 and 5 m. The products have a relatively low weight with high strength. It is used for gas and water supply, ventilation, laying heating mains and constructing garbage chutes. The connection of asbestos-cement pipes of this type is carried out using a self-sealing coupling.

Asbestos-cement pressure pipes have four classes based on operating pressure. Each class according to GOST is conventionally designated VT, followed by the operating pressure number.

In turn, the classes are divided into three types, depending on the internal diameter of the product. Asbestos-cement pressure pipes have the following specifications(in strict accordance with GOST 539-80):

Conventions used in the table:
d – diameter inside the pipe, mm;
S – wall thickness, mm;
M – weight of one linear meter, kg.

The production of pressure products consists of several stages. First, the Portland cement mortar is reinforced with asbestos fiber. Then the asbestos-cement pipe is kept in special steaming chambers, which significantly increases the strength of the core. The surface of the pipeline remains smooth throughout the entire period of use.

Non-pressure asbestos-cement pipes are produced in accordance with GOST 1839-80. With their help, drainage collectors, free-flow sewerage, ventilation and a gas supply system are equipped. The low weight of the pipeline allows it to be used even in areas where it is difficult to ensure the use of large construction equipment. The range of asbestos cement products includes (according to GOST 1839-80):

Conditional diameter, mm	Wall thickness, mm	Length, m	External diameter, mm	Inner diameter, mm	Weight, kg
100	9	3.95	118	100	6
150	10	3.95	161	141	9

Application for drainage device

Drainage systems closed type can be equipped with asbestos pipelines. General rules installation are as follows:

Also, asbestos cement products are used to construct wells that serve drainage networks. Asbestos cement can be laid to great depths. The walls of the products are not destroyed under the influence of an aggressive environment and do not require complex manipulations for maintenance.

Drainage pipes made of asbestos cement are easy to maintain and will last up to 20 years. Previously, asbestos products dominated the laying of drainage networks, but recently they are increasingly being replaced by more modern material– plastic. Plastic pipes have less weight, which greatly simplifies the installation process.