You need to quickly buy pipes for gas pipelines at an objectively generated value? Do you want to cooperate exclusively with a reliable and reputable company ready to offer not only a large assortment, but also favorable conditions for cooperation? In this case, you've come to the right place! Already today, our catalog contains a large selection of longitudinal and seamless hollow metal structures with various constant cross-section diameters and wall thicknesses for the equipment of gas transportation systems.

Today, electric-welded products of various diameters are used to transport a gaseous medium to equip main (ground, underground) gas pipelines, with a maximum working pressure of 12.5 MPa.

The high degree of mechanical parameters of the metal used makes it possible to use these products in zones with different climatic conditions, including areas with a prevailing subzero ambient temperature.

Pipes for gas pipelines are made of high-quality low-carbon steel, since this material and method of production does not reduce the operational parameters and does not change the formula of the transported product.

Favorable prices for pipes for gas pipelines in Moscow

Would you like to purchase used reliable metal hollow structures with high performance parameters and physical and mechanical properties? Have you looked at a ton of offers on the market, but none meet your search criteria? Looking for a quality product and objectively formed prices for pipes for gas pipelines? In this case, you simply cannot do without our professional help and the assortment presented on the pages of our website!

All products declared in our catalog undergo a special multi-stage system of quality control and compliance with the operational parameters prescribed in the current regulations and standards. The high level of quality of the products we sell was appreciated by our customers throughout Russia.

Today we are ready to provide favorable conditions for cooperation, as well as competitive prices for all products of the secondary metal market. Purchase steel gas pipe of the diameter and length you need, you can with us in an unlimited amount. We also offer prompt delivery of goods by rail or land special transport to any region of the country.

Gas pipesare made only of high quality mild steel. It is worth noting that it is never used in the production process. stainless steel, since the interaction of natural gas and this material forms withassociations that can greatly reduce the quality of the substance passing through the pipe.

Gas pipes price rather high - this is primarily due to the manufacturing technology, since this material is usually made by casting and not by rolling. The fact is that the production of rolled pipes presupposes the presence of a transverse seam, which is unacceptable when gas passes through the pipe.

Buy steel gas pipes today it is possible in many steel companies. Domestic pipes have a high level of quality, which is much higher compared to foreign ones. It should be noted that the pipes used for laying a gas pipeline can be laid out both as a route and as a technology, which is very important for the construction of serious gas facilities - gas distribution points, compressor stations and others.

The main purpose of gas pipelines is to transport combustible mixtures classified as hazardous substances. This is the reason for the requirement to use a special material in order to exclude any leaks. Already at the first stages of the general gasification, steel pipes were used for gas pipelines. And even modern analogues made of polymeric materials have not been able to oust this material from the modern market.

Categories of steel pipes and types of gas pipelines

For the laying of highways are used different types pipes for gas pipelines, which are divided into two categories:

• Seamless gas pipes can be hot or cold deformation.
• Welded pipes are distinguished by the type of seam, it can be straight or spiral.

In the production of both categories, the basis is carbon steel, the grades of which are specified in GOST 380-2005.

The chemical composition of the steel and the type and size of the gas pipe are determined by the following factors:

• Working pressure value... This parameter can be high, medium and low.
• Place of the pipeline... It can be underground, above ground, underwater, and also located indoors.
• Purpose of the system... The network can be backbone, distribution and backup.

The distribution system is designed to deliver gas to the direct consumer. Gas supply pipes can have a smaller diameter and thinner walls.

The purpose of the backup network is indicated by its name - special strategic goals. Compliance with high quality is due to the fact that the network is operated only in a certain situation.

Assortment documents

GOST 3265-75 regulates the production of water and gas pipes. These pipes are used in the assembly of distribution systems for the supply of natural gas with an operating pressure of no more than 1.6 MPa. The diameter of such pipes does not exceed 15 cm, the length ranges from 4 to 12 meters.

GOST 8734-75 specifies the range of seamless cold-deformed pipes. They are designed to work under a pressure of 10 MPa. According to the document, pipes can have an outer diameter of no more than 25 cm, and a length of 4.5 to 9 meters.

Advantages and disadvantages of steel pipes for gas pipelines

On the positive side, gas pipes are characterized by the following properties:

• High strength indicators.
• Slight linear expansion rates.
• The ability to work with a working environment with high pressure.
• Reliable sealed connection subject to the docking rules and the absence of defects.

Among the disadvantages of gas pipes are:

• Condensation due to high thermal conductivity.
• The likelihood of a corrosion process.
• Unbending.
• Labor-intensive installation by welding.

Rules for the installation of gas pipes made of steel

• Execution of works in full accordance with the design regulations.
• High-quality docking in order to avoid possible leaks during the period of use of the pipeline.
• Installation with a snug fit of the pipe to the base.
• Preservation of the anti-corrosion protection established by the manufacturer. This insulation reduces the susceptibility of the steel pipe to stray currents and prevents corrosion.
• Mandatory processing welds bituminous compositions.

Pipes used for gas pipelines, which are planned to be laid in the ground, must use special factory-made insulation. The technological process of its manufacture has its own characteristics, which makes it impossible to perform such work on the construction site. In accordance with the soil conditions, the insulating coating can be of normal or reinforced design.

Gas is supplied to all consumers through pipelines, no matter how large they are - they are huge enterprises or tenants of one-room apartments. Despite the fact that plastic pipes have begun to occupy a certain segment here in recent decades, steel pipes are still the main routes for transporting gas.

Requirements for materials

Any steel pipes for gas pipelines require mechanical and electrochemical protection against the metal corrosion process. These highly complex operations require significant financial costs. There are different ways to create a steel structure from different steel grades. Their choice is influenced by the parameters and purpose of gas pipelines, pressure, temperature regime and physicochemical properties of the transported gas.

Gas pipes are subdivided into:

• Seamless (obtained by cold or hot rolling).
• Welded, with a spiral seam along the entire length.

Pipes are made either from low-carbon steel or high-quality structural steel and must comply with GOST. Carbon, sulfur, and phosphorus are added to the metal. For underground pipelines, pipes with a wall thickness of at least 3 mm are taken, and for aboveground and aboveground ones - 2 mm.

Characteristics of steel pipes

Pipes are characterized by the following parameters:

• Internal and external wall diameter.
• Nominal bore diameter.
• Wall thickness.

Since substances are transported in pipelines at high pressures (75 atmospheres or more), strict requirements are imposed on pipes, set forth in GOST 20295-85 and many TUs.

In accordance with regulations, only the strongest steel pipes for gas pipelines can be used during construction. As a rule, longitudinal electric-welded or seamless pipes large diameter. Their material can only be high-quality carbon steels of grades 10 and 20 or low-alloy steel 17G1S.

Protection of steel gas pipelines

All types of protection of the gas pipeline must be on high level... Pipes are protected from external corrosion by means of insulation, which is most often enamel or a special film, and sometimes insulation with bitumen. The pipeline is protected from destruction, which may occur due to excess gas pressure above the permissible level, with safety valves.

Today, polyethylene pipes are widely used for laying underground gas pipelines. They are cheaper than steel ones, but no less reliable and durable. Polyethylene pipes for gas pipelines meet high operational requirements, but they are not suitable for outdoor installation indoors. HDPE cannot withstand ultraviolet and mechanical stress, therefore, in houses, wiring continues to be made of steel pipes.

What is the advantage of HDPE gas pipes

Polyethylene gas pipes have their own characteristics and advantages compared to steel or propylene counterparts. They are considered the most optimal option for transporting main gas used in domestic and industrial areas.

Among the main positive properties of using HDPE pipes are:

• a long period of service, not less than fifty years;

But do not forget that with an open laying, a polyethylene gas pipe will quickly become unusable under the influence of sunlight.

• low gas permeability of the walls, which ensures complete tightness;
• light weight;
• plastic;
• resistance to corrosive processes, including electrochemical, and aggressive chemical influences;
• trouble-free transportation of gas, due to the ideal smoothness of the inner surface;
• unnecessary use of additional protective covers;
• no need for waterproofing;
• environmental friendliness;
• frost resistance;
• low cost of pipes, fittings and installation, due to the simple technology of work performance.

Unfortunately, polyethylene pipes for gas cannot be used everywhere. This is due to multiple requirements in relation to them. First of all, HDPE pipes cannot be used in residential premises.

The destruction of the structure of the material from the action of ultraviolet radiation can lead to gas leakage, which is unsafe.

Polyethylene pipes installed on gas pipelines with high working pressure must not be laid under roads and in places where heavy loads are possible. In such cases, it is necessary to pre-lay casings or channels in which the gas pipelines will be located.

It is also impossible to use HDPE pipes for gas in regions with an increased level of seismic activity. These requirements apply to gas pipelines of categories I and II, which corresponds to operating parameters of 6-12 atm. and 3-6 atm. respectively.

Assortment and classification of products

Two types of pipes are manufactured for gas pipelines:

• PE100 - for operating pressures up to 3, 6, 10 and 12 atmospheres;
• PE80 - for operating pressures up to 3 and up to 6 atmospheres.

Products are sold in coils up to 200, sometimes up to 500 meters, or in sections of 13 meters, depending on the diameter. The HDPE gas pipe is black with markings in the form of longitudinal stripes in yellow (PE80) or orange (PE100). On its outer surface, technical data must be applied with paint of the appropriate color, indicating:

• manufacturer's name;
• purpose (gas);
• grade of polyethylene in international format (PE100 or PE80);
• SDR value;
• outer diameter and wall thickness in millimeters;
• GOST;
• date of manufacture with batch number.

Pipes for gas pipelines have a diameter of 16 to 400 mm.

MRS and SDR designations

HDPE gas pipes have designations that may puzzle the average consumer. Let's try to figure them out.

Mrs. This indicator indicates the minimum long-term strength of polyethylene. In other words, it is the HDPE's ability to withstand loads expressed in megapascals. For PE80 MRS is 8MPa, for PE100 it is 10MPa.

SDR. Translated from English - "Standart Dimension Ratio" means "standard dimensional ratio". This indicator can be represented as the ratio of the outer diameter to the wall thickness of the pipe.

It should be noted that the larger the SDR parameter, the thinner the pipe wall will be.

Installation of gas pipelines from HDPE

The main task when laying gas lines- this is to ensure their tightness. Even a child knows that a gas leak can have serious consequences, and in the worst case, victims. Therefore, the installation of gas pipelines should be approached with all responsibility.

To connect HDPE pipes, thermistor fittings are produced, which are installed at the joints by welding. In addition, crimp (compression) and split flange fittings are used.

The following are used as connecting parts:

• turns by 45 and 90 degrees:
• couplings;
• stubs;
• adapters;
• tees.

Welded seams provide the most reliable connection throughout the entire life of the pipeline.

HDPE pipes made of low-pressure polyethylene are increasingly used in the construction of gas pipelines. Contrary to the common misconception, the words “low pressure” in the name of “HDPE pipes” refer to the method of polyethylene production, and not to the category of a gas pipeline - polyethylene gas pipes can be used in gas distribution networks of low, medium and high pressure - up to 1.2 MPa.

In Europe, pipes for gas pipelines are produced in accordance with ISO 4437. Our national standard, GOST R 50838, is a modified version of this document, taking into account the typical conditions for laying and operating gas pipelines in Russia. One of the most significant changes is the ban on the use of recycled (from pipe processing) polyethylene - the original ISO 4437 does not have this restriction.
This is one of the few cases when our domestic product requirements are stricter than foreign ones.

Description of polyethylene pipes

Polyethylene pipes for gas pipelines are produced from special pipe grades of polyethylene classified as PE 80 and PE 100. The class of polyethylene is established by long-term (lasting more than a year) internal pressure tests and allows you to calculate the maximum working pressure at which the service life of a gas pipe will be at least 50 years at a temperature of 20 ° C. Pipes made of PE 100 with the same wall thickness are capable of operating at higher internal pressures than pipes made of PE 80. It is important to note that only virgin polyethylene is used in the production of gas pipes.

The product range of POLYPLASTIC Group includes polyethylene pipes for gas pipelines in accordance with GOST R 50838 with a diameter of 20 to 630 mm, as well as polyethylene pipes for underground gas distribution and gas consumption networks with a diameter of up to 1200 mm, manufactured according to
TU 2248-010-73011750-2010. All supplied products for gas pipelines have a full set of permits.

In addition to the class of polyethylene and the diameter, polyethylene pipes are characterized by the ratio of diameter to wall thickness - SDR. The lower the SDR value, the thicker the pipe wall, and the more pressure such a pipe can withstand. The POLYPLASTIC Group produces pipes for gas pipelines with SDRs from 9 to 26.

The color of the polyethylene pipe for gas transportation can be black, yellow or orange. Black gas pipes have longitudinal indelible yellow stripes that distinguish the laid gas pipeline from other pipelines. Each pipe has a marking repeated through the meter, containing information on: material, pipe size, its purpose, information about the manufacturer, batch and production date. Example of pipe marking: "Group POLYPLASTIC PE 100 GAS SDR 11 63x5.8 GOST R 50838-2009 04/15/2015 K05017-15 shift 2".

HDPE pipe properties

HDPE pipes have a number of advantages that are important both for the operating organization and for the builder, which makes them the optimal solution for the construction of gas distribution systems of any level - from gasification of a country house to the construction of gas distribution networks on the scale of a metropolis or a small settlement.

Polyethylene is an excellent insulator, due to which HDPE pipes are immune to stray currents.

Polyethylene pipes are chemically resistant to the transported natural gas, do not corrode under the influence of moisture in the ambient air, so they do not require an electrochemical protection device. In addition, due to the absence of corrosion processes during operation, there is no overgrowth of the pipe and a decrease in its throughput.

Due to its flexibility, polyethylene pipes are not damaged by soil movements, even significant ones. This allows you not to fear for their safety when laying gas pipelines in unstable soils and seismically active regions. The permissible bending radius for HDPE pipe is equal to its 25 diameters, which is almost 50 times less than that of steel pipes, which allows the use of long pipes with a diameter of up to 180 mm, supplied to the facility in coils or on coils (drums), which greatly simplifies the installation process and minimizes the number of welded joints. When using polyethylene pipes, it is possible to effectively apply various methods of trenchless reconstruction of old worn out pipelines in the cramped conditions of cities, as well as a new trenchless laying directional drilling method.

The service life of a polyethylene pipe is at least 50 years, and under favorable conditions, when the gas pressure is less than the calculated one, and its temperature is below 20 ° C, it can exceed 100 years.

HDPE pipes are significantly lighter than steel pipes, which simplifies their transportation and laying.

Unfortunately, HDPE pipes are limitedly resistant to ultraviolet rays, so such pipes cannot be used for above-ground installation. In addition, polyethylene is a combustible material, which does not allow the use of pipes made of it for laying gas pipelines indoors.

Installation of polyethylene gas pipelines

Polyethylene pipes can be connected by butt welding or by welding with parts with electric attachment heaters, while the strength of the connection, made in compliance with the welding technology, is higher than the strength of the pipe itself. Equipment required for the installation of polyethylene gas pipelines can be purchased or leased from the POLYPLASTIC Group.

A wide range of bends, equal and unequal tees allows you to build a gas pipeline of any complexity, and the AEON and GF shut-off valves supplied by POLYPLASTIC Group complete the gas distribution and gas consumption networks.

For the transition from a steel pipe to a polyethylene one, permanent polyethylene-steel joints can be used. One side of such a connection is welded to a steel pipe, the other to a polyethylene pipe.

We also supply saddle branches that are used to connect new consumers to an existing gas pipeline without reducing the pressure in it during the tie-in.

The training and certification of welders conducted by the POLYPLASTIC Group, as well as installation and installation supervision services, allows our customers to avoid problems during the construction of polyethylene gas pipelines.

The cost of polyethylene pipes

Despite the fact that polyethylene gas pipes are more expensive than pipes for water pipes, primarily due to more stringent requirements for raw materials and a wider range of necessary tests, the price of a HDPE gas pipe is lower than for steel pipes.

Due to savings at cathodic protection stations (including operating costs and consumed electricity) or the absence of the need for periodic painting of the surface of gas pipelines required for their overhead laying, as well as lower operating costs of polyethylene gas pipelines associated with their high reliability and durability, the total cost life cycle(with a longer service life) polyethylene gas pipelines (design, construction and operation) are significantly lower than steel ones.

You can buy pipes in accordance with GOST R 50838 or TU 2248-010-73011750-2010 by leaving an order on the website, or by contacting one of our regional divisions.