Piping main for gas pipeline

Today it is difficult to imagine the world and one's own life without the achievements of science and technology. Many believe that the main achievement is information development. But just imagine your life without industrial facilities! In everyday life, everyone benefits from the benefits of civilization: water, electricity, gas, heat - and can no longer imagine their comfortable lives without them. In order to deliver water and gas, water and gas pipelines are built, which act as vehicles.

During installation, builders use pipes for main gas pipelines. It is important to note that they entered our everyday life and occupied the most important position as an inexpensive means of delivering liquids and gases.

What is a pipe?

At the moment there is no single answer to this question. In general, it can be said that the pipe is an industrial product of a hollow profile that is used to transport gas, oil, various liquids, insulation, reinforcement.

Classification of pipes

Seamless pipes can be rolled (hot and cold rolling), pressed (diameter up to 820 mm) and cast (cast iron and steel, diameter up to 900 mm).

On the profile of the section, there are shaped, round:

• Square.

• Rectangular.

• Oval.

• Segmented.

• Ribbed.

• Teardrop-shaped.

• Six-, three- and eight-octagonal.

The longitudinal section distinguishes:

• Conical.

• Stepped with planted ends.

This is not the whole list of pipes, which differ in the longitudinal section. In a separate group there are bimetallic, trimetallic, consisting of several layers of metal, which are interconnected by welding, planting or melting.

The use of seamless pipes

Based on the destination are issued for:

• oil and gas industry;

• Construction;

• pipelines;

• machine building;

• vessels and cylinders.

Pipes for the oil and gas industry are made of carbon and alloy steel grades. Drill pipes are used for drilling wells of reconnaissance and operational character. Casing pipes are used to protect the walls of gas, oil wells from corrosion, liquid ingress into them, separation of gas and oil reservoirs from each other. Pipes for pipelines are used to deliver gas, oil, gasoline, water, acids. Pipe-and-pipe pipes are used in the operation of drilling wells when oil production takes place and have threaded connections. Boiler pipes are used in boilers of various designs. The main pipe is manufactured in accordance with GOST 3262-75 and is welded. Structural pipes in accordance with GOST 800-78, 8642-68 are used in the manufacture of various machine parts in aviation, engineering, automotive construction. Pipes cracking, in accordance with GOST 550-75, are made of steel 10, 20, K5M, K5, 12MX and others and are used for pumping petroleum products under high pressure.

Trumpet main

The main feature of the pipes of this assortment is a large diameter, as they are used for mounting various structures in construction, for transportation of oil, gasoline, steam, oils, gas, water.

Steel trunk pipes are made with straight and spiral strips, with a diameter of 529-2560 mm and a wall thickness of 8-25 mm. Pipes for main gas pipelines are made for work in corrosive environments, at elevated pressure and in difficult climatic conditions. Thus, the location of the main oil and gas production areas in the North of Russia necessitates the construction of powerful main pipelines located underground.

Complex climatic conditions make extremely high demands on the quality of pipes and their performance properties - strength and plastic characteristics. Sometimes the gas main pipe has a special coating: composite, zinc, bituminous.

The National Association of Corrosion Engineers (NACE) has established a standard that regulates tests and recommendations on materials resistant to wet hydrogen sulphide environments. Criteria for assessing the suitability of the material: time to failure and threshold voltage.

For pipe materials that are used in difficult climatic conditions, it is important to reduce the temperature at which the brittleness of the metal begins, increasing its viscous properties, which are determined on samples with a circular notch at a minimum temperature of -60 ° C and on samples with a sharp notch with the minimum possible Operating temperature -20 ° C. That is why it is so important to use trunk pipes manufactured according to GOST or TU.

Trunk pipe: GOST and characteristics

There are main pipes for:

1. Welding method:

• Contact welding.

• Electric arc welding.

2. Type of weld:

• Spiral seam.

• Straight seam.

3. Purpose:

• Pipes for main oil pipelines.

• Pipes for main gas pipelines.

• Pipes for main pipelines with other media.

4. Diameter:

• Pipes of large diameter.

• Pipes of small diameter.

It is important to remember that arc welding is a universal method, and the welding contact type is used only for a trumpet with a small diameter. The gas main pipe of large diameter can be trimmed, while the burrs are removed. In case the pipe is not cut, the burrs are not removed at the factory.

GOST 20295-85 is the main normative document concerning trunk pipes.

Trumpet main: assortment

As a preform for the production of the main steel pipe, a steel strip is used, the material of which is high-alloyed carbonaceous (quiet, semi-quiet) steels and low-alloyed hot-rolling steels.

Steel grades, which are used for the production of main pipes:

• 10;
• 20;
• 09GSF;
• 10Г2ФБЮ.

Trumpet main electric welded according to GOST 20295-85, TU 14-3-1573-96:

Assortment
Diameter, mm	steel grade
159	20
219	20
273	20
325	20
377	20
426	20
530	17Г1С
630	17Г1С
720	17Г1С
820	17Г1С
920	17Г1С
1020	17Г1С
1220	17Г1С
1420	17Г1С
1620	17Г1С
1820	17Г1С

As you can see, the main pipe is used in difficult geological and climatic conditions, aggressive environments and is manufactured in accordance with GOST and TU, and the large assortment only strengthened the position of the trunk pipe among other rolled metal products.