Asbestos-cement pipes are asbestos-containing pipes that are used in the automotive industry and rocketry, as well as in construction sites. They are popular for their reliability, durability and relative cheapness. In construction, these qualities are highly valued.

Not to mention, BNT pipes are very easy to work with. The 200 mm asbestos-cement pressure pipe is lightweight and easy to use.

Production and features of asbestos cement pipes

On the market building materials chrysotile cement (like BNT) pipes are a fairly well-known phenomenon. Although, asbestos pipes it is more correct to call “asbestos-cement pipes”, since asbestos itself (a mineral from the silicate class, fine-fiber) performs in this case role of reinforcement. Now their production is very intensive. This type of pressure pipe is also very suitable for sewerage.

Various asbestos cement pipes (BNT), chrysotile cement pipes for sewerage, and slate are made from asbestos cement. Despite the fact that asbestos is considered a harmful and carcinogenic material, when combined with cement (asbestos/cement ratio is 15/85 and sometimes even 100 percent) it has no harmful effect.

Due to the properties of the material, asbestos cement (BNT) and chrysotile cement pipes:

• Quite corrosion-resistant and also resistant to aggressive environments;
• Non-toxic and fireproof;
• They are light in weight;
• Resistant to temperature effects of both heat and cold;
• They are more economically profitable than their metal counterparts and are light in weight.

There are also negative qualities that are worth paying attention to:

• Due to manufacturing features, the height of the section may not be completely round, but have an elliptical shape; the asbestos-cement pressure pipe will not be perfectly straight. These cooling defects during technological process usually do not affect the characteristics of the product, but sometimes strict adherence to the form can be important for the builder (for example, when working with pressure pipelines in cramped conditions);
• Asbestos pipe is a fragile material, so when cutting and laying, you need to be careful and take this factor into account.

About types of products

The main production of asbestos pipelines is concentrated on two types, which are used for construction purposes:

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

The first asbestos, as well as chrysotile cement pipes, are used for laying pipelines (free-flow, internal or external), sewerage, for the construction of drainage collectors in drainage systems or free-flow hydraulic systems. Their production occupies about 25% of the total market.

Also, a pressure asbestos pipe (often used in the form of a box) is used when laying cables underground, communication lines, or as a columnar foundation for a low-rise building, since its weight is not very large.

The latter (like chrysotile cement) are used in irrigation systems ah pressure type, as well as in water supply systems of a similar operating principle, reclamation systems, ventilation or heating networks. Their household uses are also quite diverse.

According to GOST requirements, free-flow pipes for sewerage are produced in widths of 100, 150, 200 or 400 mm and 4 or 5 meters long. Pressure asbestos-cement ones according to GOST are produced with a diameter of 100 mm, 150 mm, 200 mm, 300 mm, 400, 500 and a length of 5 meters.

For the latter type, not only the dimensions, but also the working pressure of 6 or 9 atm are also determined. The actual width of asbestos products can reach 1 meter, which is allowed by their manufacturing technology (this is usually done “to order”).

The width table according to GOST also indicates the internal diameter and their external diameter in ratio. As well as wall thickness and throughput specific products, which can be important when using data to design a water supply system.

Application of asbestos cement pipes

The price of asbestos pipelines for chimneys or sewers has become the reason for their fairly frequent use. However, they have a significant limitation on the upper temperature limit (no more than 100 - 300 - 400 degrees).

The fact that an asbestos-cement pressure pipe for a water supply and sewerage system has good performance, will not be suitable for a chimney. Rubber seals are deformed from high temperatures, asbestos stove chimneys can simply burst from overheating.

In addition, when they are used for a chimney, this leads to a relatively greater formation of soot and absorption of condensate by the walls, which also negatively affects its strength.

Thus, using asbestos-cement pipes for a chimney is extremely fire hazardous if we are talking about coal or wood stoves. But, if we are talking about an intermediate or final segment of the chimney (sufficiently distant from the stake or stove), then this method is quite acceptable, since their weight is not very large.

When it comes to gas heating of low intensity - an asbestos pressure pipe for gas boiler may well be used. In this case, increased safety of use can be achieved if a “sandwich” model is used, which has a layer of insulation and a protective casing.

Related question: “How to insulate?” usually it is proposed to solve using mineral wool in several layers with a casing width 6 mm larger than the base diameter.

Installation and its features

The installation of these products does not have any serious features or pitfalls, except for its fragility. You can use a hacksaw or a grinder (even an ax). There are also no difficulties with drilling, but it is worth considering that due to the high density of asbestos fibers, the working tool quickly becomes dull. Because of this, installation is not very easy.

Installation (connection) between each other occurs using couplings (also made of asbestos cement) and rubber seals (rings), which avoids welding the products together. After installing the coupling, the connection between the products is poured cement mortar.

When mounting, you need to pay attention to the absence of distortions and the straight arrangement of the segments. At the stage of laying in a ditch, given the fragility of its material, it is necessary to level the recess as much as possible so as not to create preconditions for breakage.

Installation (connection) involves sealing the break with cement mortar or asbestos-cement mixture. The same scheme can be used to install a damaged pipeline segment.

Review of the characteristics of asbestos pipes (video)

Cost and reviews

The price will differ depending on their variety. The cost of a free-flow sample, depending on the width, will range from $12 per segment (4 meters long) to $35. It can be equipped with a coupling with the corresponding diameter - it costs between 0.6 and 3 dollars.

The price of the pressure version may depend on both the diameter and the operating pressure.

Products with a working pressure of 6 atm will cost on average from 40 to 100 -150 - 200 - 300 - 400 dollars. At an operating pressure of 9 atm, the cost will be from 19.5 to 100 - 300 - 400 dollars. In both cases, the length of the segment is 5 meters. The cost of a coupling with o-rings will be from 4 to 15 (20) dollars.

If it is not possible to buy pipes for a chimney or sewer separately, then an old pressure pipe will come in handy (sometimes samples left over from an old reclamation system, for example). You can use asbestos-cement in which the diameter is 200-250 - 300 - 400 mm.

When selecting a specific sample, you should also pay attention to reviews of asbestos products for chimneys, sewers, etc. After all, people’s opinions allow us to clarify several interesting points and better understand the situation. After all, it is easier to learn from other people's experiences than from your own.

Vladimir, 45 years old, Volgograd:

The house was installed (connected) to a gas boiler. So for more than 15 years I have been using asbestos pipes, which are light in weight without any complaints. Considering that I got it almost for nothing, I don’t plan to change it yet.

Leonid, 32 years old, Rostov:

Under country house they made a columnar foundation out of them, used asbestos pipes although they initially wanted metal pipes. But because they weigh less and the diameter becomes 300 - 400 mm, it turned out to be one and a half times cheaper and less labor, even than pouring a regular foundation. They say it’s difficult to make a cellar, but I don’t need one under the house.

Asbestos is a mineral. Its main advantage is tensile strength. It is widely used for pipe production. An asbestos cement pipe consists of Portland cement and asbestos in a ratio of 85% to 15%. Depending on the scope of application, the products have a cross-section from 10 cm to 1 meter.

Types of pipes

Today you can buy two types of asbestos cement pipes:

• pressure;
• non-pressure.

The first type is designed for a load of 9 atmospheres. They are produced in accordance with GOST 539-80 and differ in diameter from 100 to 500 mm and length from 3.95 to 5 m. Such products are not heavy, but very durable. They are widely used for laying gas and water pipelines, ventilation, and garbage chutes. Self-sealing couplings are used to connect the pipe line.

Pressure pipes differ in the operating pressure. Depending on this indicator, there are 4 product registers:

• VT6 – 6 kgf/cm2;
• VT9 – 9 kgf/cm2;
• VT12 – 12 kgf/cm2;
• VT15 – 15 kgf/cm2.

Non-pressure asbestos pipes are manufactured in accordance with the requirements of GOST 1839-80. They are suitable for arranging collectors, sewers, and gas supply systems. The low weight of the products makes it possible to lay the pipeline in hard-to-reach places where it is impossible to provide access for large construction equipment.

Advantages of asbestos cement pipes

The products are fully suitable for laying both above-ground and underground communications. Due to their versatility, they perform well as piles, supporting structures, and fence posts. Metal and plastic pipes significantly inferior to asbestos in many respects. Firstly, they are expensive, and secondly, they have a shorter service life.

Among the main advantages of asbestos-cement pipes are:

• Long service life. Regardless of the scope of application, the products can withstand 40 years of use without losing their qualities.
• Resistant to external factors. They are resistant to corrosion and aggressive environments.
• Easy to install. The pipes are easy to install and handle.
• Light weight.
• Increased thermal insulation. The products are resistant to freezing.
• Preservation appearance. Asbestos has repulsive properties, so pipes are not subject to fouling.

Installation features

Socket elements for asbestos-cement pipes are not produced. Their connection to each other is carried out using couplings, which are made from polymers or the same asbestos concrete. Each connecting element is equipped with sealing rings located inside, along the edges of the product.

Since the weight of the pipes is relatively small, installation of 100 mm products can be done manually using a jack. To lay thicker lines, it is necessary to use lifting equipment.

During the laying process, it is imperative to observe all slopes within the norm. The pipe should lie tightly on the base. After installation, all connection points should be checked. If the couplings are not installed tightly enough, leaks may occur in the future.

If there is a need to purchase asbestos-cement pipes or other building materials, then the largest wholesale supplier of asbestos-cement in Moscow is the AlfaCem online store. In the company's assortment big choice materials: cement, finishing compounds, pipes, slabs, fences for garden beds.

All goods are always in stock. We have our own fleet of vehicles, thanks to which orders are delivered in a short time throughout Moscow and the Moscow region. Adequate prices allow you to buy products in the required volume at any time of the year.

Asbestos cement pipes made from a mixture of asbestos-cement fiber and Portland cement, have the following advantages: low weight and low thermal conductivity.

Our information: Asbestos cement- this is fiber-reinforced concrete, that is, concrete reinforced with fiber. The asbestos obtained from the mining enterprise is mechanically crushed and fluffed until the fibers are separated, after which it is mixed in an amount of 15% with 85% of cement and water is added. This pulp is poured onto a mesh drum and the pressed film, 0.2 mm thick and the width of the future pipe, is wound on a rolling pin, achieving the required wall thickness, and therefore the strength of the pipe. During the manufacturing process of a pipe, asbestos fibers are oriented mainly tangentially, which ensures high strength when the pipe is loaded with internal pressure. Asbestos-cement is a good dielectric, therefore asbestos-cement pipelines, and even divided by rubber rings into four-five-meter electrically insulated sections, are not subject to electrochemical corrosion under the influence of stray currents and do not require cathodic protection or even waterproofing. Therefore, they do not have an equivalent replacement for pipelines in industrial zones, cities with electric transport and railway stations, where all highways are stretched along the tracks. In these conditions steel pipes They last only two years.

Asbestos-cement (asbestos-cement) pipes are easy to machine. Even with long-term use, asbestos-cement pipes retain a smooth internal surface, and they are also good dielectrics.
Like any pipes, asbestos cement pipes They also have disadvantages. These include fragility, so special care should be taken when installing them. Cracks may appear in asbestos-cement pipes during impacts and transportation. Accordingly, when choosing asbestos-cement pipes Special attention need to be turned to the ends. Material delamination and breakage are unacceptable.
The outer surface of asbestos-cement pipes is susceptible to corrosion, and this fact must be taken into account when arranging anti-corrosion protection.
Non-pressure asbestos-cement pipes (pressure grades VT6, VT12 and VTE are also used in industry) are produced with a diameter of 100 mm to 500 mm and a length of up to 5 meters. Such pipes are connected using couplings. It is allowed to use both straight cylindrical couplings made of the same material and cast iron.
Double-collar asbestos-cement collars must have rubber sealing rings. To connect pipes in sewer pipelines, it is preferable to use cylindrical asbestos-cement couplings with threads.
It is recommended to lay asbestos-cement pipes in soil that prevents subsidence in order to prevent bending of the pipeline, as a result of which its normal operation will be disrupted.
Non-pressure asbestos-cement pipes used when laying non-pressure internal and external pipelines transporting rubble and atmospheric wastewater; during construction gravity pipes extensive hydraulic structures and drainage collectors of drainage systems; when laying underground cables, communication line cables, when installing columnar foundations for light low-rise buildings, as well as in the form of support posts for fences and fences.
Pressure asbestos-cement pipes used for pressure water supply, reclamation and irrigation systems, ventilation, as casing pipes wells, as well as during the construction of heating networks. Using an asbestos-cement pipe, you can make garage floors, as well as gutters, feeders, and trays.

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 technical specifications Manufacturers of asbestos-cement products indicate the possibility of using them 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.

Asbestos cement pipes are used for laying pipelines for communications for various purposes. The material for their manufacture is highly durable, and the inner walls almost do not accumulate plaque. Asbestos-cement pipes are in demand and are considered promising due to their main characteristics, which we will discuss later.

Composition of asbestos cement

It is the composition that determines the basic properties of products. The pipes are formed from a mixture of cement binder and asbestos fibers, which act as a reinforcing frame.

Asbestos is a mineral fiber that is not afraid of heat or dampness. For this reason, asbestos cement pipes are universal; they are made as non-pressure and pressure pipes, intended for service in different conditions temperature and humidity.

Along with asbestos, chrysolite (a type of asbestos) is added to cement.

The difference between chrysotile cement pipes and asbestos cement pipes lies solely in their environmental friendliness and safety. Asbestos is a more harmful component - it can cause allergic reactions, and with prolonged contact provokes cancer. Chrysolite does not have such an effect, but it is also more expensive. Nevertheless, there is no need to be alarmed: in practice, unpleasant consequences are excluded, because the highways are buried in the ground, that is, contact with humans is excluded.

Characteristics

All pipe products made from asbestos cement must undergo a series of tests described in GOST 11310-90. To allow a product to be put into operation, it must meet several parameters:

• water tightness test by filling the pipe cavity under a specified pressure. Non-pressure products must withstand flow for 10 seconds, pressure - 30 seconds;
• bending strength and tensile strength are also checked in a water-filled state. The pipe is placed under a press, the pressure of which is brought to a given value. Within 10 seconds, the walls should not show any signs of destruction.

The pressure value for asbestos-cement pipes with different diameters and wall thicknesses is determined individually. Based on the test results, products are divided into 4 classes:

Size range

The standards for the production of asbestos-cement pipes are regulated by GOST 1839-80. The document establishes the basic parameters of the products:

• conditional pass;
• wall thickness;
• internal and external diameter;
• product length.

The nominal diameter is understood as the nominal diameter of the pipe, adopted to describe products and pipelines made from them. In this case, neither the internal nor the external diameter may correspond to the nominal one. Table No. 1 of GOST 1839-80 shows the relationships between these parameters and the others:

The dimensions of asbestos-cement pipes may differ slightly from the specified ones:

• for the outer diameter the deviation can be ±2.5…3.0 mm;
• for wall thickness along the entire length of the pipe ±1.5...2.0 mm;
• for the total length of the product, 50.0 mm is permissible except in cases agreed between the manufacturer and the customer.

Another parameter of the product – weight – depends on the dimensions. The weight of an asbestos-cement pipe can be determined conditionally due to the variability of the material: the walls tend to absorb moisture, which affects the parameter; there may also be deviations in the formulation of the solution of cement and asbestos fibers.

Advantages

Today there are many types of pipes, but asbestos cement does not lose popularity due to significant advantages over other materials:

• high bending strength (according to tests), withstand significant internal and external pressure compared to plastic and metal;
• the walls do not contribute to the settling of sludge and the growth of clogged plaques, which eliminates the need for cleaning and repair;
• the walls are resistant to corrosion on both the internal and external sides;
• long service life of at least 50 years;
• chemical inertness of asbestos cement to substances in any environment;
• pipes do not freeze and are not destroyed due to freezing and thawing, so they can be laid in the ground at any depth;
• relatively light weight;
• affordable price.

Installation

Asbestos-cement pipes are connected using special couplings made of the same material and rubber seals, for which space is provided in the part. They provide absolute tightness on the highway.

The specificity of the installation is that it is impossible to create turning sections - only in the forward direction. Sewer lines are designed with this in mind. If rotation is still necessary, metal elbows are used to implement it, but the strength of the connection will not be as high as when using an asbestos-cement coupling.

How to connect asbestos-cement pipes to each other?

• The coupling and pipe ends are lubricated with glycerin-graphite lubricant to facilitate the process;
• A coupling is put on the pipe laid in the sewer, into which the seal is already inserted, and it is inserted along the entire length of the product;
• Lay the second pipe and place the coupling on it, centering the latter in the middle.

Asbestos-cement couplings are self-sealing; tightness is ensured by the pressure of the medium inside the pipe (for pressure pipes). In non-pressure systems, the connection is already tight.

Another way is to use a polyethylene MPT coupling. It is preheated in hot water, after which they quickly pull it onto the laid pipe, then pry up the second one. As the polymer hardens, it thickens naturally.

A cast iron flange coupling of the “Zhibo” type can also serve as a connector for asbestos cement pipes. The product is put on the ends of the pipes to be connected, then the flange is tightened.

Application

Asbestos pipes have a wide range of applications:

• installation of sewer lines (non-pressure);
• highways cold water(pressure products);
• cable channels for optical and copper wire networks laid underground;
• pipes can be used as piles for small private houses;
• installation of drainage systems (for this, the pipes are perforated along the entire length);
• chimneys for stoves and fireplaces.

Pressure water pipes and non-pressure sewerage are the direct and most common purpose of pipes made of combined materials. They also work well as a backbone for wired networks - they support optimal conditions humidity, sufficient tightness, as well as resistance to soil pressure and deformation.

Piles made of pipes for the house - an economical construction option small cottages. Hollow pillars are buried in the ground and filled with frame and concrete. Such supports are in no way inferior to columnar and pile systems.

The question arises: is it possible to use an asbestos-cement pipe for a chimney?

If we compare the chimney from different materials, asbestos cement is not the best solution:

• the material can withstand heating only up to +300°C. Exceeding the temperature will cause the pipe to burst. For this reason, installing a chimney directly from the boiler is completely excluded;
• Condensation is a real problem with asbestos cement. The material absorbs moisture, which is saturated with fuel combustion products, and then released when there is a temperature difference. As a result, wet spots may “float” along the wall and roof. In addition, the caustic solution destroys the pipe walls over time;
• It is impossible to remove soot from the pipe, and it accumulates at a decent rate. As a result, it often ignites;
• installation of inspection hatches for pipe maintenance is impossible.

Also remember that asbestos is harmful to human health. Of course, the pipe can be installed outside the living space, where the smoke temperature is already acceptable. Nevertheless, the problem of condensation and soot removal remains relevant. The solution to the problem can be insulation and lining of the pipe.

Conclusion

Pipes made from asbestos and cement are durable, strong and inexpensive, this excellent material for the installation of straight-line water supply and sewerage, the organization of a drainage system in the ground and a pipeline for cables within the city. The construction of a foundation from pipes with a diameter of 200-300 mm also does not cause concern. To organize chimneys, it is still not recommended to use asbestos cement if the house has a modern, efficient boiler (in the case of a regular old-style stove - please).