Asbestos-cement pipes, the sizes of which vary depending on the purpose, are used in the construction of industrial and residential buildings, and are also used for equipment of roads and communications. The popularity of the material is due to the inclusion of asbestos and cement with water, which increases the strength of the product over the entire surface. Consider the features of such structures.
Composition
Asbestos-cement pipe, the dimensions of which are indicated below, are of two types: chrysolite or amphibole type. Any of these modifications includes hydrogenated sodium silicate (asbestos). This natural material is environmentally friendly, does not pose a radioactive or other hazard. When working with such elements, certain safety measures are also required, since inhaled asbestos dust can provoke the development of cancer of the respiratory tract (especially with prolonged contact).
As for the dangers, the most problematic are the amphibole asbestos of the acid-resistant type. Their use and extraction has recently been banned, which is aimed at maintaining the health and life of workers. The first negative opinion about such materials was formed during the Second World War. Then amphibole parts were used on military ships.
The asbestos-cement pipe (dimensions in this respect do not matter) of the chrysolite type does not adversely affect the human body. Its fibers and particles are capable of dissolving in an acidic environment and excreted from the body within 10 days. By the way, even cellulose analogues require much more time.
Specifications
An asbestos-cement pipe, the dimensions of which we will consider later, is produced by chemical mixing of asbestos fibers and cement composition. The result is a unique material that becomes safe for the human body, since further dust is not observed.
In 2001, the Russian Ministry of Health adopted a decree on hygiene standards related to the use and processing of asbestos cement. According to them, such products are not dangerous; they are compared in terms of the level of threat to the body with many other materials used in industry and everyday life.
As an example: at the Sukholzhskabocement plant (Sverdlovsk region), among 700 employees, not a single case of cancer was registered. The manufactured products are in demand not only in the domestic market, but also abroad. More than one million kilometers of pipes of this nature are produced in Russia, and the total annual turnover is about 3 million km.
Asbestos-cement pipes: sizes, GOST
The main requirements for the products under consideration in terms of state standards are presented below:
- Diameters inside and outside in asbestos pipes must comply with GOST 539-80.
- Testing and testing of products is carried out in accordance with GOST 11310-90.
Since in the Soviet Union asbestos-cement pipes were used mainly for the arrangement of drainage channels, their use was significantly limited. In this regard, special state standards were not provided, since this material was not used at civil and industrial construction sites.
After the change in the political system, asbestos-cement pipes, the dimensions of which are discussed in more detail below, began to be used in various fields. As a result, there was a need to create certain documentation regulating the diameter, composition, thickness and other parameters of the product.
SNiP
The updated SNiP 41-02-2003 includes such requirements that are oriented to non-metal pipes:
- When used in heating systems, the temperature should not exceed 115 degrees, and the working pressure - 1.6 MPa.
- It is allowed to use asbestos-cement pipes of identical sizes for open and closed type hot water supply systems.
- Asbestos-cement pipe (dimensions are not important) can be used for the construction of cold water supply pipelines. In this case, metal analogues require the creation of additional verification and related documentation.
Asbestos-cement pipes: dimensions, diameter
In the Russian Federation, a draft law on technical regulation has been adopted, which sets out the standards for the production and use of asbestos cement products. They take into account the technical conditions in each case. The length of such materials is from 3.9 to 5 meters.
Asbestos-cement pipe (dimensions):
- 100 mm
- 150 mm.
- 200 mm.
- From 250 to 500 mm.
An interesting fact: during the time of the Soviet Union in Simferopol laid a water pipe from the material in question, whose length was about 20 kilometers. The diameter of the pipes was more than 700 millimeters. Now this production is not widely used due to the complex production technology and the increased mass of each element.
Production
Asbestos cement is a concrete solution that is reinforced with fibers or asbestos fibers. The production technology of this material is as follows:
- After extraction, untreated asbestos is subjected to mechanical grinding.
- The material is then fluffed to separate the fibers.
- Cement with asbestos is combined in a proportion of 85 and 15 parts. Then they add water, making pulp.
- The suspension is placed on a drum with holes.
- Next is a thorough mixing of the composition.
After extraction, a kind of film remains, which is equal to the size of asbestos pipes 100 mm. This material is wound until the desired product dimensions are obtained. When buying such products, you must require an epidemiological certificate to guarantee the safety of your health and life.
Mounting
Laying pipes from the material in question is as follows:
- Pipes with a cross section of 200 mm or more require additional processing to obtain the necessary dimensions and roughness.
- The connection is made using special couplings equipped with grooves with o-rings. This design makes it possible to ensure a tight pressure against the walls of the pipe at a significant internal pressure of water.
- At the connection points of the couplings, a radial clearance is sure to be left. This is necessary for the technical deflection of the pipeline if the o-ring fails.
- Installation of an asbestos-cement pipe with a size of 150 millimeters and its analogues is indented from adjacent ends. This makes it possible to avoid the installation of linear expansion joints.
For reference: the linear expansion of asbestos-cement pipes is 12 times less than the identical parameters of similar steel products. When heated to 100 degrees Celsius, the asbestos modification increases by 0.4 mm, while the rubber seal is deformed by the end parts by 0.2 mm.
Scope of application
Due to the fact that asbestos cement belongs to the group of dielectrics, individual isolated five-meter sections do not collapse under the influence of stray current. In addition, such sectors do not require special waterproofing.
Such qualitative parameters make asbestos-cement pipes in demand not only in industry, but also in the arrangement of residential, railway and urban communications. Even under critical operating conditions, the service life of the material is at least two years. Its main advantages are the ability to use in various fields of life with minimal financial and labor costs. The most effective way to lay asbestos-cement pipes is considered to be channel-free laying, which simplifies the design and subsequent installation.
Benefits
Asbestos-cement pipes have a lot of advantages, caused by working in different directions. Savings are achieved in the following aspects:
- Mounting trays.
- Minimization of waterproofing measures.
- The presence of cathodic protection.
- No additional mineral wool insulation is required.
- The presence of operational humidity control during the operation of polyurethane pipes.
- Simplified arrangement, thanks to couplings with o-rings, which are easily installed at the ends of the products.
Total
As a result, it can be noted that asbestos-cement pipes are one of the most optimal options for arranging various spheres of human activity. It is worth noting that the use of analogues from other materials is sometimes unacceptable or inappropriate.