You need to promptly buy pipes for gas pipelines at an objectively determined cost? Do you want to cooperate exclusively with a reliable and reputable company that is ready to offer not only a large assortment, but also favorable conditions for cooperation? In this case, you have come to the right place! Already today, our catalog presents a large selection of straight-seam and seamless hollow metal structures with different constant cross-section diameters and wall thicknesses for equipment of gas transportation systems.
Today, for the transportation of gaseous media, electric welded products of various diameters are used to equip main (ground, underground) gas pipelines, with a maximum operating pressure of 12.5 MPa.
The high degree of mechanical parameters of the metal used makes it possible to use these products in areas with different climatic conditions, including areas with prevailing sub-zero ambient temperatures.
Pipes for gas pipelines are made from high-quality low-carbon steel, since this material and production method do not reduce operational parameters and do not change the formula of the transported product.
Favorable prices for pipes for gas pipelines in Moscow
Do you want to purchase used, reliable, hollow metal structures with high performance parameters and physical and mechanical properties? Have you looked at a lot of offers on the market, but none of them 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 listed in our catalog undergo a special multi-stage quality control system and compliance with operational parameters prescribed in current regulations and standards. The high level of quality of the products we sell is 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 market of rolled metal. Buy steel gas pipeline pipe You can find the diameter and length you need in unlimited quantities. We also offer prompt delivery of goods by rail or overland transport to any region of the country.
Gas pipeline pipesare made only from high-quality low-carbon steel. It is worth noting that during the production process it is never used stainless steel, since when interacting natural gas and this material is formed fromcompounds that can greatly reduce the quality of the substance passing through the pipe.
Gas pipes price quite high - this is due, first of all, to the manufacturing technology, since this material is usually made by casting rather than rolling. The fact is that the production of rolled pipes requires the presence of a transverse seam, which is unacceptable when gas passes inside 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 is worth noting that the pipes used to lay a gas pipeline can be laid out both as a route and as a technology, which is very important when constructing serious gas facilities - gas distribution points, compressor stations and others.
Polyethylene pipes are widely used today for laying underground gas pipelines. They are cheaper than steel ones, but no less reliable and durable. Polyethylene pipes for gas pipelines meet high performance requirements, but they are not suitable for open installation indoors. HDPE cannot withstand ultraviolet and mechanical stress, so wiring in houses continues to be made from steel pipes.
What is the advantage of HDPE gas pipes
Polyethylene gas pipes have their own characteristics and advantages compared to steel or propylene analogues. 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:
- long service period of at least fifty years;
But do not forget that when the gasket is open, polyethylene pipe will quickly deteriorate when exposed to 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, thanks to the ideal smoothness of the inner surface;
- there is no need to use additional protective covers;
- no need for waterproofing;
- environmental friendliness;
- frost resistance;
- low cost of pipes, fittings and installation, due to simple technology for performing the work.
Unfortunately, polyethylene gas pipes cannot be used everywhere. This is due to multiple requirements in relation to them. First of all, HDPE pipes cannot be used in residential areas.
Destruction of the material structure from ultraviolet radiation can lead to gas leakage, which is unsafe.
Polyethylene pipes installed on gas pipelines with high operating pressure are prohibited from being laid under roads and in places where extremely intense loads are possible. In such cases, it is necessary to first lay casings or channels in which the gas pipelines will be placed.
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 correspond 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 working pressures up to 3, 6, 10 and 12 atmospheres;
- PE80 – for working pressure up to 3 and up to 6 atmospheres.
Products are sold in coils of up to 200, sometimes up to 500 meters, or in sections of 13 meters, depending on the diameter. Gas pipe HDPE is black in color with markings in the form of longitudinal stripes of yellow (PE80) or orange (PE100). on her outer surface Technical data must be applied with paint of the appropriate color, indicating:
- name of the manufacturer;
- 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 from 16 to 400 mm.
Designations MRS and SDR
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, this is the ability of HDPE to withstand loads expressed in megapascals. For PE80 MRS is 8MPa, for PE100 – 10MPa.
SDR. Translated from English, “Standard Dimension Ratio” means “standard dimensional ratio”. This indicator can be expressed as the ratio of the outer diameter to the pipe wall thickness.
It should be noted that the higher the SDR parameter, the thinner the pipe wall will be.
Installation of gas pipelines from HDPE
The main task when laying gas lines is to ensure their tightness. Even a child knows that a gas leak can have serious consequences, and worst case- and victims. Therefore, the installation of gas pipelines should be approached with all responsibility.
To connect HDPE pipes, thermistor fittings are produced and installed at the joints by welding. In addition, crimp (compression) and detachable flange fittings are used.
The following are used as connecting parts:
- 45 and 90 degree turns:
- couplings;
- plugs;
- adapters;
- tees.
Welds provide the most reliable connection throughout the entire period of operation of the gas pipeline.
The main purpose of gas pipelines is to transport flammable mixtures classified as hazardous substances. This is the reason for the requirement to use a special material to prevent any leaks. Already at the first stages of general gasification, steel pipes were used for gas pipelines. And even modern analogues made of polymer materials have not been able to displace this material from the modern market.
Categories of steel pipes and types of gas pipelines
For laying highways they are used different types pipes for gas pipelines, which are divided into two categories:
- Seamless gas pipes can be hot or cold deformed.
- Welded pipes They 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, as well as the type and size of the gas pipeline, are determined by the following factors:
- Working pressure value. This parameter can have a high, medium and low value.
- Pipeline location. It can be underground, above ground, underwater, or 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 may have a smaller diameter and thinner walls.
The purpose of the backup network is indicated by its name - special strategic purposes. Compliance with high quality is due to the fact that the network is operated only in a certain situation.
Documents regulating the assortment
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-formed pipes. They are designed to operate 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 from 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.
- Insignificant linear expansion indicators.
- Ability to work with high pressure working environments.
- Reliable sealed connection, subject to the joining rules and absence of defects.
Among the disadvantages of gas pipes are:
- The appearance of condensation due to high thermal conductivity.
- The likelihood of a corrosion process occurring.
- Inflexibility.
- Labor-intensive installation by welding.
Rules for installing steel gas pipes
- Carrying out work in full accordance with the design provisions.
- High-quality joining to avoid possible leaks during the period of use of the pipeline.
- Perform installation with a tight fit of the pipe to the base.
- Preservation of the anti-corrosion protection installed by the manufacturer. This insulation reduces the steel pipe's susceptibility to stray current and prevents corrosion.
- Mandatory treatment of welds with bitumen compounds.
Pipes used for gas pipelines that are planned to be laid in the ground must use special factory-produced insulation. The technological process of its manufacture has its own characteristics, which makes it impossible to carry out such work on the construction site. In accordance with the ground conditions, the insulating coating can be of a regular or reinforced design.
Gas is supplied to all consumers through pipelines, no matter how large they are - huge enterprises or residents of one-room apartments. Despite the fact that some segment here in recent decades began to be occupied by plastic pipes However, the main pipelines for gas transportation are steel pipes.
Material requirements
Any steel pipes for gas pipelines require mechanical and electrochemical protection from the process of metal corrosion. These highly complex operations require significant financial expenses. Eat different ways creating a steel structure from different brands become. Their choice is influenced by the parameters and purpose of gas pipelines, pressure, temperature regime and physical and chemical properties of the transported gas.
Gas pipes are divided into:
- Seamless (obtained by cold or hot rolling).
- Welded, having a spiral seam along the entire length.
Pipes are made either from low-carbon steel or from 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 ground and above-ground pipelines - 2 mm.
Characteristics of steel pipes
Pipes are characterized by the following parameters:
- Inner and outer diameter of the wall.
- Nominal diameter.
- Wall thickness.
Since substances are transported in pipelines when high pressures(75 atmospheres or more), then the pipes are subject to strict requirements set out in GOST 20295-85 and many specifications.
In accordance with regulatory documents, only the strongest steel pipes for gas pipelines can be used during construction. As a rule, straight-seam electric-welded or large-diameter seamless pipes are used. Their material can only be high-quality carbon steel grades 10 and 20 or low-alloy steel 17G1S.
Protection of steel gas pipelines
All types of gas pipeline protection must be high level. Pipes are protected from external corrosion by insulation, which is most often used enamel or a special film, and sometimes bitumen insulation. The pipeline is protected from destruction that may occur due to gas pressure exceeding the permissible limit by safety valves.
