The exceptionally wide use of the circular pipeline is explained by its main feature: with a minimum external surface area, the product has a maximum internal volume. So far, it has not been possible to come up with something more perfect for moving liquid and gas products.

Round pipe: varieties

With a minimum difference in the composition of the feedstock, steel conduits markedly differ in quality. The reason for this is the manufacturing method. It is also determined by the use of products.

Electric pipe

Of all types of metal, it has the lowest strength characteristics. But at the same time, these qualities themselves are so high for steel products that the vast majority of water and gas pipelines are constructed from electrically welded options.

The manufacturing method includes cutting the strip - tape, folding it into a workpiece and welding along the seam. Steel round-section steel pipes are divided into 2 types, depending on the location of the weld pipe.

• A product with a direct longitudinal seam - regulated by GOST 10704-91, used for pressure and pressureless supply systems of all kinds. The seam is considered weak. A pipeline is produced with a diameter of 10 to 1420 mm and a wall thickness of 1 to 32 mm.

This is the most popular type of metal, its range includes the largest number of sizes.

• Products with a spiral seam - in this case, the tape is folded in a spiral, and, accordingly, is welded in a spiral. The strength characteristics of this option are much higher, and the cost is much less than that of a seamless-rolled pipeline. The assortment of pipes of circular cross section with a spiral seam includes products of large diameter - from 150 to 2520 mm with wall thicknesses from 3.5 to 25 mm. In the photo you can see the samples.

Hot Rental

This type of product belongs to the category of seamless piping and is highly resistant to internal and external pressure.

The workpiece here is a solid metal bar. It stretches through the piercing mill, where it turns into a hollow cylinder. Heating molding is accompanied. The hot workpiece is fed to the rollers, where it is stretched and crimped to the specified sizes.

There is no seam in this case. The product is more resistant to corrosion.

GOST for pipes of circular cross section - 8732-78, regulates the size and chemical composition of products. The range includes products with diameters from 29 to 550 mm and wall thicknesses from 2.5 to 75 mm.

Cold formed pipes

The manufacturing process differs little from the molding of hot rolled products. However, all the described actions are performed without heating. But since cold deformation contributes to the appearance of tension on the surface of the products, after molding the finished pipeline undergoes heat treatment. This method gives products an unusually high strength and accuracy. For aircraft and instrumentation, for example, only cold rolled products are used.

Products are regulated by GOST 8734-75. Assortment steel pipes  circular cross section includes products with a diameter of 5 to 250 mm and a wall thickness of 0.3 to 24 mm.

Additional items

When installing any system, in addition to the main elements, additional ones are required. These details may be absolutely necessary or, conversely, optional, but their use facilitates installation and gives a more aesthetic appearance.

Plugs on a pipe of circular cross-section can be divided into decorative and functional.

• The first include metal elements made in the form of balls or even figures. They protect the piping from moisture or debris. Their typical application is stubs on the fence. Polymer and rubber are much less aesthetic: their role is reduced only to protection.
• Functional designed to ensure the operation of the system. With partial dismantling or repair, a plug is installed in place of the cut branch. In emergency situations, when the line breaks in this way, the consequences of the rush are minimized. Several types of plugs are used.
  • Threaded - the thread can be internal or external, the plug itself - round faceted or grooved and even quite decorative. Jammed with its help conduits with a size of not more than 50 mm.
  • Flange is a flange without holes, bolted with the appropriate gasket to ensure tightness. It is used on products with a diameter of more than 50 mm.
  • Rubber pneumatic plug - used in emergency situations.

Steel pipes are widely used in a wide variety of industries. They are used in mechanical engineering, the oil and gas industry, utilities, etc. There are several types of steel. They can differ in the method of manufacture, size and type of material used for the production. The assortment of steel pipes of different types is determined by GOSTs.

Seamless products

Basically, all modern steel pipes are divided into two large groups: hot-rolled and welded. The first variety has a higher cost. Therefore, such products are used less often than welded ones. The range of steel is determined by GOST 8732-78. The ratio of the size of such pipes and their weight is given in special tables. The parameters may, for example, be as follows.

The size	Weight 1 m

The range of steel pipes electrowelded and made by means of furnace welding will be examined by us a little later. Their parameters are also precisely determined by GOSTs.

How to make seamless pipes

Products of this variety are produced from steel grades 35 and 45 on a continuous mill. In this case, the so-called black blanks are used. The latter are stitched on a roll mill, and then sent to a circular saw to trim the end of the pipe. Then the finished product enters the Kosovalkovy mill for dressing and reducing the ovality of the cross section.

Welded pipes: reasons for popularity

Products of this type, as already mentioned, are more popular than seamless. Such pipes have been used in the national economy for quite some time. However, in recent years, their popularity has increased significantly. This is primarily due to the development of new, more advanced welding methods, allowing to obtain the most reliable and durable products. So, for example, in 1941 only 38.8% of welded pipes were produced. The rest was seamless. At the same time, the proportion of electrowelded was only 0.8%. By 1965, these indicators increased to 50% and 35%, respectively.

Scope of use of welded pipes

Today, such products are used everywhere. Most often they are used for laying various kinds of highways designed for pumping oil, gas, water, etc. Also, this type of pipe is usually used in public utilities. In this case, they are used for laying water pipes and sewer systems. Welded pipes are also used for the assembly of gas elevated highways, drainage systems, etc.

Engineering is another area in which welded pipes are used. They are also used for the manufacture of various kinds of architectural elements: peaks over porches, awnings, children's swings, horizontal bars, etc. In agriculture, irrigation systems are assembled using them.

The main varieties of welded pipes

Products of this type can vary in:

Any construction products are manufactured subject to certain conditions and standards. And although many materials obey the requirements of one single GOST, a steel round pipe, depending on the technology of its manufacture, refers to different standards.

Round pipe application

The main application of steel pipes is their use as pipelines designed to transport gas and various liquids, which are most often water and oil products. Depending on the transported medium, pipes may have:

• galvanizing;
• anticorrosive coloring;
• polymer coating;
• processing with insulating materials.

In addition, the surface of the pipes is subjected to electrical processing or other types of protection. The most “painful” for steel pipes are corrosion processes. Excessive moisture provokes them from the outside, and internal roughnesses and butt welds from the inside. Appearing, corrosion gradually begins to grow, thereby reducing throughput and filling the inner space of the pipe. Breaks and leaks result in unscheduled repairs and pipe replacements.

Another area of \u200b\u200bapplication for galvanized round pipes is the furniture industry. They are widely used in the manufacture of frames and the internal content of wardrobes or wardrobes. Also, GOST for round steel pipes allows the use of material in the assembly of metal structures or individual metal products.

Differences and features of steel pipes

The main classification of round steel pipes is made according to the method of their manufacture:

• electric welded are available in two types - straight-seam and spiral-seam;
• seamless.

They also have differences in rolling methods:

• cold forming;
• hot forming.

An electric-welded round steel pipe is made of steel strips or sheet metal by molding with subsequent welding of the seam along the axis or in a spiral. The process involves the use of special equipment. Spiral tubes are much less common than straight-seam pipes, and they are obtained by forming a strip in a spiral. In this case, the joint is welded at the same time continuously with a special seam. In the manufacture of products, two types of welding are used:

• high-frequency contact - for pipes from 10 to 530 mm;
• electric arc - from 428 to 1420 mm.

Visually, the seam during high-frequency welding is practically invisible. The technology of electric arc welding provides for the imposition of three seams, which increases the strength characteristics of the joint. First, the main central seam is laid, and then the connection is boiled from the outer and inner sides of the product.

Electric-welded pipes, the diameter of which allows for internal work, are cleaned (ground) from the inside, removing bumps and bulges formed after welding. If it is impossible to carry out such work, the inner surface remains without treatment.

Seamless steel pipes are made in several ways:

• pressing;
• drawing
• forged;
• rolling;
• centrifugal casting.

Hot forming is performed on special equipment. The workpiece, at the same time, is heated to the temperature of recrystallization. This method allows to obtain high-strength products that can withstand severe loads, including internal pressure. Cold formed round metal pipe  receives the given sizes by cold deformation on the equipment intended for this process.

The difference between seamless and electric-welded pipes is the presence or absence of a weld. Their manufacturing methods have a significant dissimilarity of technologies, and, as a result, different specifications.

Manufacturers produce several more types of steel pipes:

• soldering;
• with metal or non-metallic coating;
• with special processing - turned, polished, polished.

The most common today are water and gas (HSV) and electric-welded straight-seam (ESW) pipes. They are widely used in urban and suburban housing construction when performing engineering networks. They are cheaper than seamless analogs, thanks to a simpler technology for the production and use of ordinary, most affordable carbon steel in metallurgy.

Depending on the type of molding, in the manufacture of pipes BS are based on different regulatory documents:

• for hot formed ones - GOST 8732-78 and GOST 8731-74;
• for cold formed ones - GOST 8734-75 and GOST 8733-74.

Each of the documents indicates in what form a round steel pipe should be produced, product range, tolerances, installation, acceptance and storage rules, and much more.

GOST 8732-78 defines the dimensions of the outer diameters of seamless hot formed pipes ranging from 20 to 550 mm with a wall thickness of 2.5 to 75 mm. Also, the tables indicate the mass of products in kilograms per linear meter. The document says that pipes, with respect to length, can be made:

• measured;
• multiple dimensional;
• unmeasured;
• approximate lengths based on consumer orders.

Typical is a length of 4-12.50 meters. But at the request of the customer they depart from this rule.

GOST 8731-74 indicates the technical requirements for hot-formed seamless pipes. It sets the valid:

• steel grades;
• yield strengths;
• temporary tear resistance;
• elongations.

The regulations require that there are no cracks and flaws on the surface of the pipes, but minor dents and traces of stripping are allowed. Products are allowed to be cut off with autogenes or plasma cutting, but only if the wall thickness reaches 20mm or more.

With a thickness of steel seamless pipes up to 20 mm, it is recommended to cut chamfers during the manufacturing process for the convenience of welding.

GOST 8734-75 defines which assortment round cold-formed steel pipes may have. Their measured length varies between 4.5–9 meters, and unmeasured can be 1.5–11.5 meters. By wall thickness and diameter, they are divided:

• especially thin-walled - 0.3 ... 0.5 mm with a diameter of 5-40 mm; 0.3 ... 1.0mm with a diameter of 42-170mm; 0.3 ... 4mm with a diameter of 180-250mm;
• on thin-walled - 0.6 ... 1.5 mm with a diameter of 5-40 mm; 1.2 ... 3.2 mm with a diameter of 42-170 mm; 4.5 ... 24mm with a diameter of 180-250mm;
• on thick-walled - 1.6 ... 1.8 mm with a diameter of 5-40 mm; 3.5 ... 7mm with a diameter of 42-170mm
• especially thick-walled - 2.0 ... 24 mm with a diameter of 5-40 mm; 7.5 ... 24mm with a diameter of 42-170mm

GOST 8733-74 regulate the technical requirements for cold and heat-deformed pipes. In particular, this relates to the material of manufacture.

The standard describes the same characteristics as in GOST 8731-74, relating to seamless pipes, as well as the rules for acceptance and testing.

The range of steel pipes with a spiral seam is specified in GOST 8696-74. The standards apply to general-purpose pipes and do not apply to oil pipelines, as well as main gas pipelines. Their outer diameter is in the range of 159-2520mm, and the wall thickness is 3.5 ... 25mm.

Long spiral tubes are made of 10 and 12 meters, but the standards allow in extreme cases the production of short products of at least 6 meters. GOST also defines acceptable indicators:

• deviations
• edge offsets;
• ovality;
• curvature.

The same document provides product specifications.

Straight seam welded pipes

The range of steel pipes of this variety is presented in GOST 10704-91. Unmeasured products are available in the length of 2 ... 5 meters. Measured pipes can have sizes of 5 ... 12 meters. Moreover, their diameter is 10-1420 mm with a wall thickness of 1.0 ... 32 mm. Deviations and tolerances are considered in the document separately and in sufficient detail.

Technical characteristics of longitudinal steel pipes are presented in two regulatory documents:

• GOST 10705-80;
• GOST 10706-76.

They define:

• mechanical properties of metal;
• the presence of seams and the correctness of their location;
• marginal deviations;
• the presence of defects;
• process and types of tests;
• acceptance requirements.

Steel pipe marking

Each steel pipe is marked with the requirements of GOST 10692-80. It emphasizes that products with a diameter of more than 159 mm are subjected to this procedure. At the same time, the wall thickness should not be less than 3.5 mm. Marking is done in several ways:

• rubber stamp;
• electric pencil;
• electrograph;
• branding;
• indelible paint by hand.

Smaller pipe diameters are labeled, especially if the products are delivered in bags.

The marking shall indicate:

• steel grade;
• name of product;
• pipe size;
• trademark of the manufacturer.

On seamless pipes, in addition, the wall thickness and batch number are applied.

Packing and transportation

Products with a diameter of up to 159 mm are tied in bags or packed tightly in wooden containers or boxes. The linkage is made by wire in at least three places. Pipes over 159mm are tied exclusively into transport bags.

It should be noted that the packing wire is not allowed to be used for dangling. For this, special clamps must be provided.

Moving steel round pipes to an object is allowed by any type of lengthy freight transport. During storage, stacks are separated by gaskets.

GOST on seamless hot-rolled pipes

• GOST 8732-78 Hot-deformed seamless steel pipes.
• GOST 550-75 Seamless steel pipes for the oil refining and petrochemical industries.
• GOST 9940-81 Seamless hot-deformed pipes from corrosion-resistant steel.
• GOST 23270-89 Pipe blanks for machining.
• GOST 30564-98 Seamless hot-deformed pipes from carbon and alloy steels with special properties.

GOST for seamless cold-rolled pipes

• GOST 8734-75 Cold-deformed seamless steel pipes
• GOST 9941-81 Seamless cold and heat-deformed pipes from corrosion-resistant steel
• GOST 10498-82 Seamless especially thin-walled pipes made of corrosion-resistant steel
• GOST 14162-79 Steel tubes of small sizes (capillary)
• GOST 19277-73 Seamless steel pipes for fuel and oil pipelines
• GOST 9567-75 Precision steel pipes
• GOST 24030-80 Seamless pipes from corrosion-resistant steel for power engineering
• GOST 1060-83 Cold-deformed seamless steel pipes for shipbuilding
• GOST 11017-80 Seamless steel pipes of high pressure
• GOST 21729-76 Structural cold and heat-deformed pipes from carbon and alloy steels

National Steel Pipe Standards

GOST list on steelpipes

1. GOST R ISO 3183-3-2007 Steel pipes for pipelines. Technical conditions Part 3. Class C pipe requirements
2. GOST R ISO 3183-2-2007 Steel pipes for pipelines. Technical conditions Part 2. Class B pipe requirements
3. GOST R ISO 3183-2009 Steel pipes for pipelines of the oil and gas industry. General specifications
4. GOST R ISO 3183-1-2007 Steel pipes for pipelines. Technical conditions Part 1. Class A pipe requirements
5. GOST R ISO 10543-99 Seamless steel and pressure welded steel pipes. Ultrasonic Thickness Gauge Method
6. GOST R ISO 10332-99 Seamless and welded steel pressure pipes (except for pipes made by submerged arc welding). Ultrasonic Continuity Control Method
7. GOST R ISO 10124-99 Seamless and welded steel pressure pipes (except for pipes made by submerged arc welding). Ultrasonic stratification control method
8. GOST 28548-90 Steel pipes. Terms and Definitions
9. GOST 20295-85 Welded steel pipes for gas and oil pipelines. Technical conditions
10. GOST 8734-75 Cold-deformed seamless steel pipes. Assortment
11. GOST 8645-68 Steel rectangular pipes. Assortment
12. GOST 11017-80 Seamless steel pipes of high pressure. Technical conditions
13. GOST 10706-76 Longitudinal electric-welded steel pipes. Technical requirements
14. GOST 10704-91 Electric-welded steel pipes. Assortment
15. GOST 9567-75 Steel pipesprecision. Assortment
16. GOST 8731-74 Hot-deformed seamless steel pipes. Technical requirements
17. GOST 8646-68 Steel pipes with hollow ribs. Assortment
18. GOST 8644-68 Flat oval steel pipes. Assortment
19. GOST 8642-68 Oval steel pipes. Assortment
20. GOST 8638-57 Drop-shaped steel pipes. Assortment
21. GOST 6856-54 Steel pipes of special profiles
22. GOST 5654-76 Hot-deformed seamless steel pipes for shipbuilding. Technical conditions
23. GOST 8639-82 Steel square pipes. Assortment
24. GOST 8467-83 Steel drill pipe nipple joints for exploration drilling. Technical conditions
25. GOST 13663-86 Steel profile pipes. Technical requirements
26. GOST 30456-97 Metal products. Sheet metal and steel pipes. Impact Test Methods
27. GOST 12132-66 Electric-welded and seamless steel pipes for the motor industry. Technical conditions
28. GOST 11249-80 Steel convoluted steel pipes, two-layer. Technical conditions
29. GOST 10707-80 Cold-deformed steel pipes. Technical conditions
30. GOST 10692-80 Steel pipes, cast iron and connecting parts to them. Acceptance, labeling, packaging, transportation and storage
31. GOST 8733-74 Seamless steel pipes cold-deformed and heat-deformed. Technical requirements
32. GOST 8732-78 Hot-deformed seamless steel pipes. Assortment
33. GOST 8696-74 Electric-welded steel pipes with a spiral weld for general purposes. Technical conditions
34. GOST 5005-82 Cold-deformed steel pipes for driveshafts. Technical conditions
35. GOST 3262-75 Steel water-gas pipes. Technical conditions
36. GOST 1060-83 Cold-deformed seamless steel pipes for shipbuilding. Technical conditions
37. GOST 550-75 Seamless steel pipes for the oil refining and petrochemical industries. Technical conditions
38. GOST 19277-73 Seamless steel pipes for oil pipelines and fuel pipelines. Technical conditions
39. GOST 10705-80 Electric-welded steel pipes. Technical conditions
40. GOST 10692-2014 Steel pipes, cast iron and connecting parts to them. Acceptance, labeling, packaging, transportation and storage

GOST list on copper and brass tthe ruby

1. GOST 617-2006 Copper and brass pipes of circular cross-section for general purposes. Technical conditions
2. GOST 21646-2003 Copper and brass pipes for heat exchangers. Technical conditions
3. GOST R 52318-2005 Copper pipes of circular cross section for water and gas. Technical conditions
4. GOST 16774-78 Copper pipes of rectangular and square section. Technical conditions
5. GOST 494-90 Brass pipes. Technical conditions

Pipe - GOST for each type of pipe

Specialists of Lador Komplekt LLC are always happy to highlight the technical features of the proposed pipe rental. Note that these products have a wide scope of application - including those used as fence posts, for laying a pipeline, etc. According to the method of production, steel pipes are divided into several types. The first look is seamless gOST pipe  8732-78, GOST 8734-75, GOST 10796-76, GOST 20295-85 (outer diameter of pipes 1-820 mm, special purpose - 1420 mm). The second type is a pipe made of ingots and tube billets by pressing or rolling.

The third type is welded gOST pipe  3262-75, GOST 10705, GOST 10707, GOST 3262, GOST 8639, GOST 8645, GOST 8642 (outer diameter of pipes 8-1620 mm, special purpose - up to 2500 mm and more) from sheet and strip steel with preliminary molding. This type of pipe is in special demand.

For several years now, our company has been a participant in the domestic market for metal pipe rolling, and the practical experience gained during this time gives a significant advantage over many similar enterprises and organizations. Dynamic development and flexible corporate policy allow us to optimally satisfy the wishes of customers, no matter how difficult the task was to solve, and sometimes the time is very limited.

We will promptly and correctly help you make the right choice, helping you in consultation. We remind you that GOST 13663-86 and round electric pipes are also made of electric welded rectangular and square pipes. welded pipe, its GOST 10705-91 (diameter from 10 to 530 mm) or round gOST pipe  10706-76 (diameter from 478 to 1420 mm). The fourth type is cast pipes (outer diameter of pipes is 50-1000 mm) obtained on pipe foundry machines.

Despite the fact that the modern construction market is replenished with polymer products, metal structures do not lose their positions. They are used quite widely. Steel pipes are durable and highly reliable. They are durable and easy to install. Assortments define numerous GOSTs. They should be considered in more detail. For example, a round pipe VGP (water and gas) is used very often when carrying out large highways.

Basic GOSTs

Features of the metal profile depend on the production conditions in which it was manufactured. It must comply with a specific GOST. There are many documents that govern the production of such products. It is worth getting acquainted with the main GOSTs:

Each of these documents has certain features. Some of them should be considered in more detail.

Assortment of square patterns

A metal profile, which differs in cross section in the form of a rectangle or square, is more common when transporting gas and water. However, it is successfully used in construction and in the furniture industry.

Mass has a large role in determining the quality of the metal profile. This is specified in document 2591. If the metal profile is made of steel with a density of 7.85 g / cu. cm, one meter of the profile should weigh 0.269 kg in the case of the thinnest round pipe. Thick-walled products will have an indicator of 70.33 kg.

GOST 2591 also refers to the curvature of the rental, which has a square shape. This indicator should not be more than 0.5% of the length of the metal profile if it has a diameter of 25 mm. For a metal profile that has a diameter of more than 25 mm, such a strain rate should not be more than 0.4%.

Important! The range of steel pipes made in a closed type is defined in document 12336.

Profiles manufactured according to the 8645 standard can be made both hot-rolled and cold-drawn. Seamless designs are more durable. However, they are of great value. Because of this, they are used quite rarely.

Square and rectangular metal profiles are usually welded. Thanks to the use of modern technology, strength control is possible. In the process of creating such a rental, induction current is used. Such products have a relatively low price. Seams left after welding are subjected to special treatment.

Galvanized profiles are also made. Sometimes, finished products are galvanized. For this, the metal profile is lowered into a container with zinc.

GOST, which regulates the production features and technical data of steel pipes, does not classify such profiles by groups allocated in connection with the brand. According to GOST, when creating a profile pipe, black steel can be used. In terms of its characteristics, it is inferior to many more expensive brands.

The steel metal profile, regulated by GOST 8645, may have different sizes. More popular products with a smaller side of 40 mm, with a large - from 60 mm. Profile products, the larger side of which exceeds 6 cm, have excellent bending strength. Moreover, they have a relatively small mass.

Assortment of round profiles

A round steel pipe is used in the construction of pipelines through which water and gas are transported. As in the case with profile designs, such products are made in different ways. They can be seamless or sutured. Round pipes are the most popular products.

Important! The range of round pipes is regulated in accordance with the features of their production.

The production of hot-formed seamless steel profiles is a very complex process. That is why such products are of high cost. Hot-deformed profiles are created in special conditions that require high system strength. Any malfunctions can lead to leakage of molten metal.

As raw materials, a special metal billet is used. After heating, a sleeve is created. At first it has an irregular shape. Smooth profiles become after rolling.

Such products are cut into 4-12.5 m. They may have a measured length. According to GOST, hot-rolled round pipes usually differ slightly from each other in the wall thickness. They may also vary in diameter.

Seamless galvanized round pipe can be made cold-deformed. Moreover, the production and characteristics of such products are regulated by GOST 8734. The scheme by which the production is carried out is quite simple.

Steel welded profiles

Longitudinal electric welded profiles can have various diameters. They are used to create industrial highways. There are several provisions of the document defining their characteristics:

• Round pipes made using welding can have a curvature of 1 running meter of not more than 1.5 mm for products that are thermally processed. Raw pipes have a permissible curvature of 2 mm.
• When passing through the heat treatment profile, the customer may require that this process be carried out in special conditions.
• The ends of the pipe are cut off.

For industrial steel profiles used for gas and oil pipelines, there is a separate GOST.

Total

As you can see, there are many documents that determine the production of steel structures. They regulate their range and characteristics. They should be considered when buying metal. Features of its use are also established by certain documents. Some products can only be used under certain conditions.

Standards established in a particular year may change over time. Therefore, when viewing a document should pay attention to footnotes. Perhaps it has already been replaced with a new one.