Metal pipes dimensions, wall thickness. Steel pipes for heating, their types and technical characteristics

Quality metal pipes, actively used in housing construction and infrastructure development, are controlled by GOST. Regulatory documents prescribe what steel pipes should be like: a table of diameter and wall thickness determines the product as thick-walled or thin-walled and limits the operating conditions.

Thick-walled pipes

The range of thick-walled pipe products includes monolithic seamless and welded pipes with a round diameter. The knees have high strength, able a long period withstand high internal pressure.

Types of material

The “thickness” indicator has specific limits. The framework is dictated by GOST: the wall thickness of a steel pipe classified as thick-walled must be within the limits of the coefficient 6-12.5 according to the formula for the ratio of metal thickness to outer diameter. An indicator less than 6 classifies the product as particularly thick-walled. The latter type of pipes is manufactured according to special orders from industrial enterprises in the space and aviation industries and is not a mass-sold material.

Size chart for thick-walled pipes

Mass-produced thick-walled steel pipe is supplied to the buyer in three types:

measured from 4.5 to 9 meters long;
unmeasured 1.5–11.5 meters long;
multiples of measured 1.5–9 meters.

The last type is prepared for cutting into segments: the length of the knee includes the size of each element and allowances for cutting. The allowance size for thick-walled products is 5 mm: this allows you to divide the element with a standard factory cloth and clean the edges, preparing the assembly for assembly.

An indicator of quality is the type of product. It is assigned depending on the type of material used and the principle of pipe production:

group B - pipes made of steel with a minimum level of oxidation;
group C - from heat-treated material;
group D - units that do not have requirements for the use of a specific material, but with requirements for resistance to water hammer and passing the appropriate control tests;
group E - heat-treated pipes with a strict list of mechanical characteristics.

By common standards any produced product is controlled and marked industrial enterprises thick-walled steel pipe: product dimensions, corresponding internal and external diameters are listed in the corresponding production tables. The most common units, standard for many jobs, have a diameter from 16 to 70 mm. Locking elements, fittings and mounting devices for them are mass produced.

Scope of application

The main purpose of pipes is to transport liquid and gaseous media. Thick-walled pipes are used for installation of long-distance communications, high pressure long distances. Seamless hot-deformed assemblies are a priority increased strength, for example, thick-walled steel pipe GOST 8732 78. The type of medium determines optimal material: For liquid containing soda, alkali resistance is required, and for transporting gases, minimal porosity is required. A common material that meets these requirements is steel 45: a thick-walled pipe of this quality is used for the manufacture of large-scale water supply units.

General requirement to the range used in construction, the automotive and aircraft industries, drilling and delivery of minerals - tightness, strength, absence of cracks, “shells”, cavities in the thickness of the material and chips.

Features of thin-walled pipes

To characterize thin-walled pipes, the same formula is used with the ratio of wall thickness to the outer diameter of the product. A thin-walled steel pipe can be considered as such if the coefficient obtained by the formula is in the range from 12.5 to 40. A separate category of especially thin-walled pipes combines units with a material thickness of less than 0.5 mm. These are elements used in medicine and science, the production of which is carried out by specialized enterprises, and not by pipe-rolling plants.

Mode of production

Technologies for the production of thin-walled pipes:

Hot or cold forming, in which the material is extruded through a press, which gives the elbow the shape of a cylinder. Rolling gives the product its final shape.
Electric welding, in which the consumable element for making a pipe is a metal sheet. It is bent and welded, then formed using a rolling machine. There are two common types of industrial welding: TIG and HF.

The rolling machine standardizes both the thickness of the pipe walls and the shape of its cut.

round;
square and rectangular;
oval.

Manufacturing other types of pipes is possible according to individual order.

Area of use

Thin-walled pipes are a material used in many industries. Their strength makes it possible to install local pipelines from such units. In this case, seamless pipes are a priority.

Welded pipe and profile samples are used in construction and decorative finishing facades, interiors, furniture. Polishing technique outer surface and the microseam, which is not noticeable either visually or to the touch, allows us to produce bright glossy products that are not afraid of moisture and temperature changes. Fences and railings for stairs, gates and landscape decor.

Video: flaw detector - pipe quality control system

Working with pipes is also possible at home: craftsmen roll and bend units at homemade machines. It is worth considering that the absence automated control and testing conditions affect the quality of products. It is not recommended to subject such systems to high loads.

When it comes to pipe products, as a technological characteristic we're talking about not only about the diameter, but also about the wall thickness. When this parameter changes, the nature of operation, as well as use cases, also changes. steel pipes. All characteristics of manufactured pipe products are expectedly specified in national standard. The wall thickness of a steel pipe according to GOST strictly depends on the size; these are two interdependent and correlating parameters for any steel pipe.

Standards governing steel pipe wall thickness and other characteristics

When selecting appropriate products and analyzing suitable characteristics, keep in mind that there are several standards.

First of all, they are designed for different technologies production:

GOST 10704-91 regulates the requirements for the production of electric-welded straight-seam pipes;
GOST 3262-75 describes steel water and gas pipelines;
GOST 8732 – seamless hot-deformed.

The range of each of the listed types implies requirements for wall thickness, which also depends on the nature of the technology used for production (reflected in the tables in the appendices to each standard). For example, seamless hot-formed products have higher tensile strength than others. These products are designed for a specific type of work that dictates durability and performance requirements. Strength will depend on wall thickness, steel grade (in in some cases), production technologies.

In general, the diameter and wall thickness of steel pipes made using casting technology (standard 8732) implies a wall from 2 to 45 mm with sizes ranging from 20 mm to 550 mm, respectively; conventionally, the wall thickness is approximately 1/10 of the size. The parameters can be analyzed in more detail using the appropriate regulatory standard.

Steel electric-welded straight-seam

In straight-seam welded products, the metal thickness increases in increments of 0.2 mm. According to the standard, the wall thickness of electric welded steel pipe is from 1 mm to 32 mm. This is the only technology that produces products with a 1 mm wall.

When choosing straight-wood ones based on size and required metal strength, keep in mind that the seam is made with reinforcement. It is this gain that affects the total weight of the product and is approximately 1%. These products are suitable for a number of jobs and are made of sheet steel. The wall also depends on the passage opening of the product. More detailed information on the relationship between thickness and size, as well as the weight of the product, can be found in the corresponding section of the standard.

Steel water and gas pipelines

Steel water and gas pipes are made in different assortments, characteristic of the category.

The standard stipulates following types pipe products(see photo):

light;
ordinary;
reinforced.

For example, for an outer size of 10.2 mm, the parameter will vary in the following values: 1.8, 2.0, 2.5, respectively. The same dependence is typical for standard pipe products with an internal diameter of 20 mm, the metal thickness is 2.5, 2.8, 3.2 mm, respectively.

When purchasing, specify what kind of pipe you are interested in - light, ordinary or reinforced, and not just standard inner diameter 20mm. When changing this parameter, the strength of the metal will change water and gas pipe with one diameter.

Seamless hot-deformed steel

This type of pipe is the most expensive to manufacture and sell. By analogy with the previous category, some craftsmen want to find several options for carrying out work. This is one of the installation options engineering systems. In this case, pipes are also divided into especially thick-walled, thick-walled and thin-walled. Depending on this parameter, the final weight is calculated, and the parameters include the maximum possible pressure in the system. Minimum – from 3 mm.

Where to find information

Comprehensive information about the dependencies between parameters and operating features is in the standard. It contains tables that allow you to calculate the weight of the pipe, as well as familiarize yourself with the available range of pipes. Keep in mind that the standard regulates what a manufacturer can produce, but not the units and volume of products. You can usually find the most popular pipe options on sale.

For example, straight-seam electric-welded steel pipes with wall thickness are indicated in the standard tables, from which data on the weight of the pipe can be obtained. If you are not satisfied with the weight, use pipe products made from lighter materials. Please note that lightweight materials may not withstand water pressure. A pipe with 1 mm metal is available only in the electric welding production method.

Every owner of his own home strives to make his home a cozy “nest”. Enormous efforts are being made to achieve this goal.

This includes a detailed calculation finishing works, search for exclusive furniture sets, development unique design landscape. Only all the efforts may be useless if the house is cold.

Therefore, maximum attention should be paid to the installation of the heating network and thermal insulation of the house. While doing this work, there comes a time when it is necessary to buy heating pipes.

Which pipes to choose from the variety presented? Polypropylene, reinforced plastic or copper? What if it's steel?

Until recently, this option was the most common. The systems were installed from steel pipes. Because there was no alternative at that time.

But, despite this, they cannot be regarded as a relic of the past. There are situations when this option is the most optimal solution for a specific situation.

For example, in an autonomous network, where there is a need to lay large-volume pipelines, laid steel pipes for heating called the right decision.

The main advantage steel pipelines consider their strength. It is very difficult for them to be damaged by mechanical action.

Small linear increase rate. And, a big plus of steel materials is their excellent high temperature tolerance.

They withstand very high temperatures. Also in such heating it can... If the welding work in this heating system is carried out professionally, then there is no threat of depressurization of such a network.

Perhaps one significant flaw steel products- This the complexity of their installation. To connect network sections you must use welding machine and use a professional welder.

The cost of a specialist’s work will not be cheap, and the dimensions of these building materials create difficulties during installation.

Consumer criteria for steel pipes for heating are determined by their technical characteristics:

Mode of production. Seamless pipes are considered the most highly durable because the seam becomes a weakened area on the product. As a covering.
Diameter. The internal volume determines the dimensions of the pass. This is an important indicator for a pipeline.
Wall thickness. Structural stability and the ability to withstand increased pressure depend on this.
Top coating. The galvanized shell protects these materials from corrosive influences. Chrome plating is used as a decorative element in the manufacture of furniture.
Perforation. This type of pipe is used as casing when drilling wells. True, in this area these materials are gradually giving way to plastic types.

Due to their technical characteristics, these pipes are used in many areas. If you list them, it will be easier to indicate those areas where they are not used.

Electric welded pipe for heating

Specifications

In production electric welded pipe for heating in the following ways:

Electric welded with a straight seam.
Electric welded with a spiral seam.
Seamless hot-deformed.
Seamless cold rolled.

And the process itself takes place in the following sequence:

A sheet of steel wrapped in a roll is unwound and cut into longitudinal strips.
The strips are twisted into an endless ribbon, and this is necessary for trouble-free production.
The tape is deformed by rollers, and it turns into a round pipe with an open seam.
The seam is welded. Several types are used for this welding work: arc, induction currents, laser, plasma.
The round workpiece is calibrated using rollers.
Eddy currents or ultrasound constantly monitor the seams.
Next, cutting into pieces of the required length is performed.

Seamless pipelines

Steel seamless pipe for heating is made by hot deformation from a monolithic part that has the shape of a cylinder. They are called differently - solid-bent.

Specifications

This rolled metal product does not contain any seams or joints. They are made on special machines.

Depending on the type of production, seamless materials can be hot-rolled, solid-formed or cold-rolled.

Solid bent products get their name from the production method. This type of building materials is characterized by high strength. Also, seamless options are classified as thick-walled blanks.

For production in this case they take special type become. Various non-ferrous metals are also used for such production. This is used for pipe rolling, which transports aggressive chemicals.

When talking about this type of product we cannot ignore interesting fact. Hot rolled pipes found extensive use in cryogenic technology.

Steel corrugated pipe for heating began to be used quite recently. But, her excellent qualities led to the widespread distribution of these products.

In comparison with other analogues, corrugated types have shown their superiority. They cope well with their tasks, ranging from supplying hot coolant to servicing the transportation of low-temperature environments.

Thanks to the efforts of the developers, the corrugated pipe turned out to be very easy to install; even amateurs can handle this work. To create pipeline bends, you do not need to use special equipment.

Experts predict a great future for corrugated products. Time and the development of technology will tell how successful this will be. And at this time they are confidently moving to a leading position.

Pipe diameters

Specifications

For example, when repairing heating in a house, the diameter must be calculated so that in cold weather the whole house is heated evenly.

The following diameters are designated:

Conditional. It is designated “conventional diameter” - Du. This is the nominal internal volume measured in inches.
Nominal. These values are given in letters “nominal diameter” - Dn.
External diameter. . Small - from 5 to 102 mm. Average – from 102 to 426.
Wall thickness of workpieces. This accompanying indicator is also very important.
Internal volume of steel products. And this indicator is one of the main ones. It refers to connecting elements pipeline sections.

IN different areas construction use various pipes. In this regard, we developed regulations. For example, a table with indicated volumes. Special formulas are also used for calculations, which greatly simplifies the work and saves a lot of time.

Wall thickness

The thickness of steel pipes for heating is calculated using special formulas. When making calculations, round up. These materials are produced with a wall thickness of at least half a millimeter.

In accordance with GOST standards, during measurements it cannot be less than the calculated value, determined taking into account the characteristics of use.

We must not forget that heating network- This is a highway that is characterized by high temperatures. Taking this into account, the wall thickness of the pipes used is calculated. For example, for products with a thickness from 25 to 325 mm, residual values from 10 to 45 mm are selected.

Stability calculations determine the thickness size. At the same time, we must not forget about the corrosive characteristics of the environment passing through this network. And when determining the wall thickness, the conditions of use, temperature and pressure inside the network are taken into account.