GOST 8734 85 cold-formed seamless steel pipes. Pipes steel seamless cold-formed. Basic technical requirements for cold-formed pipes

Technological process The production of cold rolled pipes is characterized by two key points:

After passing through the piercing mill, the workpiece is cooled with water and passes all operations at a temperature below the plasticity point. The name "cold-rolled" is very conditional - undergoing deformation, the metal releases a significant amount of heat.
Before the final calibration, the cold-formed pipe GOST 8734-75 is subjected to annealing. It is reheated to the recrystallization temperature, after which it gradually cools down. This makes the metal more ductile and viscous and forces it to get rid of internal stresses that have arisen during the deformation process.

Cold-formed pipe: requirements of GOST 8734-75

The range of diameters of cold-rolled tubular products produced at ChTPZ is 5-250 mm with a wall thickness of products of 0.3-24 mm.

The state standard distributes the assortment of cold-rolled seamless pipes into four groups according to wall thickness.

Particularly thin-walled pipes. Have an outside diameter to wall thickness ratio > 40.
Thin-walled pipes. They have a ratio of outer diameter to wall thickness of 12.5-40.
Thick-walled pipes. They have a ratio of outer diameter to wall thickness of 6-12.5.
Particularly thick-walled pipes. Have a ratio of outside diameter to wall thickness< 6.

Tubular products having a diameter of ≤ 20 mm can be classified into two categories according to the absolute value of their wall thickness. Products with wall thickness< 1,5 мм, относятся к тонкостенным. Трубы с толщиной стенок < 0,5 мм считаются особо тонкостенными.

Although state standard sets the dimensions of the rolled pipe in terms of the outer diameter and wall thickness, the customer may require the manufacturer to use the dimensional parameters for the inner diameter and wall thickness, as well as both the outer and inner diameters and wall thickness.

Limit values for deviation of inner diameter values pipe products should not be higher than the corresponding values limit errors by outer diameter.

For round tubes with inside diameter≤ 10 mm, the limiting values of errors for the inner diameter are set individually, within the framework of an agreement between the manufacturer and the customer.

In terms of ovality and wall thickness variation, the pipes should not exceed the maximum deviations in the outer diameter and wall thickness.

Also GOST 8734-75 prescribes that the curvature of any section cold-formed pipe per 1 meter of length did not exceed the following values:

3 mm - for products Ø 4-8 mm;
2 mm - for products Ø 8-10 mm;
1.5 mm - for products Ø > 10 mm.

At the request of the customer, the curvature parameter of products Ø 20-90 mm should not be higher than 1 mm per 1 m of pipe length. Please note that for pipes with an outer diameter to wall thickness ratio ≤ 50, not subjected to heat treatment, the parameters of permissible curvature are set individually, in agreement between the manufacturer and the customer of the pipe.

Pipe material and a list of technical requirements for them are presented in GOST 8733-74.

Basic technical requirements for cold-formed pipes

According to the above-mentioned state standard, there should be no cracks, captivity, flaws, shells and sunsets on the surface of finished products. In this case, the presence of individual minor nicks, scales and their traces is allowed, which do not interfere with inspection, as well as small dents, traces of editing, scratches and traces of cleaning of previously detected defects. The listed defects are within the limits of the norm in the event that they do not take the dimensions of the pipe-roll beyond the maximum deviations.

If a slight scale is found, the surface of the pipe can be cleaned of it at the request of the customer.

GOST 8733-74 prescribes to cut the ends of products at a right angle and clean them from burrs. When removing burrs, chamfers are allowed.

At the request of the customer at the ends of the products to be welded, with a wall thickness< 5 мм, фаски снимаются под углом 35-40° к торцу. При этом оставляется торцовое кольцо трубы шириной 1-3 мм.

Pipe-rolling under pressure must withstand the test hydraulic pressure of the set value (pipe operating conditions are agreed with the consumer). The resistance of the pipe design to hydraulic pressure is ensured by the technology of their production.

At the request of the customer, rolled products must withstand hydraulic pressure, which is calculated according to the formula prescribed in GOST 3845, not higher than 20 MPa. At the same time, by agreement between the customer and the manufacturer, it is allowed to test pipes under a pressure of more than 20 MPa.

As an alternative to hydrotesting, inspection of each product is possible non-destructive method, which ensures that the products comply with the standard values of the test hydraulic pressure.

At the request of the customer, heat-treated pipes made of steel grades 10, 20 and 15XM must withstand one or more (depending on the purpose and operating conditions) technological tests for bending, expanding, flattening and beading.

Rolled pipes with a diameter of ≤ 160 mm and a wall thickness of ≤ 8 mm are subjected to expansion tests on a mandrel with a taper ratio of 1:10 until the outer diameter increases, prescribed in GOST 8733-74.
The flattening test is applied to products having a diameter ≥ 22 mm and a wall thickness ≤ 10 mm.
The beading test must be passed by products with an outer diameter of 25-160 mm with a wall thickness of: no more than 10% of an outer diameter of 60 mm; no more than 8% of the outer diameter 60-108 mm; no more than 6% of the outer diameter 108-140 mm; no more than 5% of the outer diameter 140-160 mm.

Flanging angles:

for pipes made of steel grade 10 - 90 °;
for pipes made of steel grades 20 and 15XM - 60 °.

The width of the folded side, measured from inner surface product, should be at least 12% of its internal diameter and at least 1.5 wall thickness values.

What else does GOST 8734-75 “Cold-formed seamless steel pipes” say?

Products with a "diameter/wall thickness" ratio greater than 50, with Ø ≥ 100 mm, as well as products with a "diameter/wall thickness" ratio< 4, изготавливаются исключительно по согласовании необходимой техдокументации с потребителем.

Gosstandart also allows a slight ovality and variation in the thickness of the pipe. Tolerances for the diameter and thickness of the walls act as a limitation. If the indicators of wall variation and ovality do not take the pipe beyond these tolerances, then the pipe complies with GOST.

The curvature of any section of the pipe, taken in random order, per linear meter should not be higher:

3 mm (with Ø 2-4);
2 mm (at Ø 8-10 mm);
1.5 mm (for Ø > 10 mm).

In addition, the described GOST allows the possibility of supplying pipes without finishing heat treatment by prior agreement between the manufacturer and the customer. In all other cases, firing of finished pipes is mandatory.

It is possible to supply pipes outside the standards with wall thickness, which is limited only by the dimensions of the workpiece. These pipes are not actually cold rolled, since they are made by longitudinal drilling of a pre-calibrated blank.

Seamless cold-formed steel pipes GOST 8734-75: applications

Seamless steel pipes manufactured by cold deformation are used in main pipelines, as elements of boiler plants, are used in a variety of engineering structures, in the production of machine parts (in auto, aircraft and shipbuilding), chemical equipment, furniture fittings and many other technical fields.

Specific areas of application of seamless steel cold-rolled pipes are determined by the following technical and operational properties of this type of pipe:

complete absence of a seam;
highest tensile strength;
the possibility of their manufacture with the thickest possible walls;
minimal chance of leaks (which is their key competitive advantage before welded counterparts).

Here is a list of areas of application of cold-rolled seamless pipes.

Hydraulic systems. Thick-walled steel cold-formed seamless pipes are commonly used as the basic structural element for the manufacture of hydraulic cylinders. Pipes are able to withstand extremely high pressure piston and is widely used on super-heavy lifting special equipment.
Energy industry. Seamless cold-rolled pipes are used as heat sinks in boilers. Not only the ability of the pipe to withstand rupture by steam pressure from the inside, but also the resistance of the structure to burnout from the outside depends on the wall thickness of the product. The use of seamless pipes in boilers is highly justified in terms of profitability and service life.
Oil production. Pipe products are used throughout the entire oil production cycle. Products different types are used directly when drilling a well, for installing casing in it, as well as for pumping oil and transporting it through an oil pipeline. Tubing is capable of withstanding rock pressure of hundreds of atmospheres.
Chemical industry. Here, thick-walled pipes cold-formed according to GOST 8734-75 are used at some stages of oil refining and gas polymerization. These technological operations in the petrochemical industry are associated with enormous pressures.
Aviation, automotive and shipbuilding. In these industries, the high tensile strength of the used pipe is generally not required. However, much greater value acquires tightness. Seamless steel pipes reduce the possibility of leakage of liquids and gases by definition - they do not have a seam.

Cold-formed steel pipe GOST 8734-75: main advantages

The key advantage of solid pipe is the absence of seams. This quality makes them extremely reliable and minimizes the risk of fluid leaks. The absence of a welded seam greatly increases the strength of products compared to welded ones.

Cold formed tube made of thick sheet metal, characterized by high anti-corrosion properties. It should be borne in mind that stainless steel pipes are not flexible. This must be taken into account when carrying out construction and installation work.

Seamless pipe can be produced from a wide range of grade steels (10, 20, 35, 45, 10G2, 15X, 20X, 40X, 30XGSA, 15XM, 09G2S), which are characterized by varying degrees of thermal conductivity and temperature indicators linear expansion.

Seamless pipe connection

The fundamental difference between the methods of joining seamless electric-welded pipes cannot be distinguished. In some cases, the choice of method is influenced by the wall thickness.

The connection of especially thin-walled pipes that do not have rolled threads is carried out exclusively by gas welding. Conventional electric welding of especially thin-walled pipes is, as a rule, risky and does not bring results - the pipes burn through.

Thin-walled pipes are also welded exclusively with gas. This is true, including in the case of installing thin-walled steel pipes for heating.

It is widely practiced to connect thin-walled pipes to threads. If the threading technology is followed, the connection is extremely reliable, and the absence of a weld minimizes the risks of violating the integrity of the pipe structure. Particularly thin-walled pipes cannot be cut; any cutter cuts through them.

Electrodes are used for welding thick-walled pipes. Welding is carried out only after chamfering. If this is not done, the strength of the pipes suffers due to the weakness of the weld. Thanks to the chamfer, the pipe is welded through the entire thickness of the metal.

Warehouse complex ChTPZ sells cold-rolled seamless pipes in accordance with GOST 8734-75 in the range of diameters 95-250 mm with a wall thickness of 1.5-24 mm from steel grades 10, 20, 35, 45, 10G2, 15X, 20X, 40X, 30XGSA, 15XM , 09G2S. Minimum order for the production of cold-rolled pipes according to GOST 8734 - this is 100 meters for thin-walled pipes and 1 ton for drawn pipes.

Seamless steel tubes cold deformed. Range

GOST 8734-75

MKS 23.040.10 OKP 13 4400, 13 5100

Introduction date 01.01.77

1a. This standard fully complies with ST SEV 1483-78.

(Introduced additionally, Amendment No. 2).

1. Outside diameter, wall thickness and theoretical mass of pipes must correspond to those indicated in Table. 1.

(Revised edition, Rev. No. 1).

2. Depending on the ratio of the outer diameter (D H) to the wall thickness (s), pipes are divided into:

especially thin-walled with D H /s more than 40 and pipes with a diameter of 20 mm or less with a wall of 0.5 mm or less;

thin-walled with D H /s from 12.5 to 40 and pipes with a diameter of 20 mm or less with a wall of 1.5 mm;

thick-walled at D H /s from 6 to 12.5;

especially thick-walled with D H /s less than 6.

3. Along the length of the pipe must be made:

random length from 1.5 to 11.5 m;

measured length from 4.5 to 9 m with maximum deviations along the length of +10 mm; by order of foreign trade organizations, pipes are manufactured measured length from 4 to 9 m with maximum deviations along the length of +10 mm;

length, multiple measured, from 1.5 to 9 m with an allowance for each cut of 5 mm (unless another allowance is specified in the order) and with maximum deviations of overall length no more than specified for tubing length.

(Revised edition, Rev. No. 3).

4. Limit deviations in the outer diameter and wall thickness of pipes should not exceed those indicated in Table. 2.

5. By agreement between the manufacturer and the consumer, pipes can be manufactured with combined maximum deviations, for example, in terms of outer diameter - increased accuracy according to GOST 9567, and in wall thickness - normal accuracy, or with one-sided dimensional tolerance. The value of one-sided tolerance should not exceed the sum of two-sided limit deviations given in Table. 2. In this case, the value theoretical mass 1 m of pipes is calculated by the arithmetic mean of the sum of the plus and minus limit deviations given in Table. 2.

where D n - outer diameter, mm; s is the wall thickness, mm.

When determining the theoretical mass of 1 m of pipes, the steel density of 7.85 g/cm 3 is taken as the initial value.

2. At the request of the consumer, it is allowed to manufacture pipes with a diameter of 4 mm with a wall thickness of 0.2 to 1.2 mm, diameters of 125 and 133 mm with a wall thickness of 2.0 to 20 mm, as well as dimensions of 295.5; 328.5; 331.5;33 8.0; 393.0; 415.5; 43 8.0; 443.0; 463.0; 46 6.0; 55 9.0; 584.0 and 848.0 mm.

3. Pipes with a diameter of 100 mm or more with a D h /s ratio of more than 50 and pipes with a D h /s ratio of less than 4 are supplied according to the technical documentation agreed with the customer.

Table 2

4, 5. (Changed edition, Rev. No. 2).

6. Pipes must be manufactured according to the outer diameter and wall thickness. At the request of the consumer, pipes must be manufactured according to the inner diameter and wall thickness, as well as according to the outer and inner diameters and wall thickness.

Limit deviations for the inner diameter of pipes should not exceed the corresponding limit deviations for the outer diameter.

For pipes with an inner diameter of 10 mm or less, the maximum deviations in the inner diameter are set by agreement between the manufacturer and the consumer.

7. The ovality and wall thickness of the pipes should not take their dimensions beyond the limit deviations, respectively, in terms of the outer diameter and wall thickness.

8. The curvature of any section of the pipe per 1 m of length should not exceed:

3 mm - for pipes with a diameter of 4 to 8 mm;

2 mm - for pipes with a diameter of 8 to 10 mm;

1.5 mm - for pipes with a diameter of more than 10 mm.

At the request of the consumer, the curvature of pipes with a diameter of 20-90 mm should not exceed 1 mm per 1 m of length.

Note. For pipes with a ratio of outer diameter D h to wall thickness s equal to 50 or more, manufactured without heat treatment, the curvature standards are established by agreement between the manufacturer and the consumer.

(Revised edition, Rev. No. 2).

9. Pipe material and technical requirements to them - according to GOST 8733.

EXAMPLES OF CONVENTIONS

Pipe with an outer diameter of 70 mm, a wall thickness of 2.0 mm, a length that is a multiple of 1250 mm, made of steel grade 20, delivered according to chemical composition(for group B) GOST 8733:

The same, 6000 mm long (measured length), made of grade 20 steel, delivered according to mechanical properties and chemical composition (according to group B) GOST 8733:

The same, with combined limit deviations (on the diameter of increased accuracy according to GOST 9567, on the wall thickness of normal accuracy):

The same, random length, with delivery without standardization of mechanical properties and chemical composition, but with an indication of the hydraulic pressure value (according to group D) GOST 8733:

Pipe with an inner diameter of 70 mm and a wall thickness of 2.5 mm of random length, made of steel grade 40X, delivery according to group B in accordance with GOST 8733:

The same, made of grade 10 steel, supplied according to mechanical properties, controlled on heat-treated samples, and according to chemical composition (according to group G) GOST 8733:

INFORMATION DATA

1. APPROVED AND INTRODUCED BY Decree State Committee standards of the Council of Ministers of the USSR dated 13.10.75 No. 2604

2. REPLACE GOST 8734-58

3. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

4. The limitation of the validity period was removed by the Decree of the State Standard of the USSR dated 11/11/91 No. 1714

5. EDITION with Amendments No. 1, 2, 3, approved in August 1978, November 1981, March 1988 (IUS 9-78, 2-82, 6-88)

Buy pipes GOST 8734-75

INTERSTATE STANDARD

ASSORTMENT

Official edition

Standartinform

UDC 669.14-462.3:006.354

INTERSTATE

Group B62 STANDARD

COLD-WORKED SEAMLESS STEEL PIPES

Assortment

Seamless steel tubes cold deformed. Range

MKC 23.040.10 OKP 13 4400, 13 5100

Introduction date 01.01.77

la. This standard fully complies with ST SEV 1483-78.

(Introduced additionally, Amendment No. 2).

1. The outer diameter, wall thickness and theoretical mass of pipes must correspond to those indicated in Table. 1.

(Revised edition, Rev. No. 1).

2. Depending on the ratio of the outer diameter (P n) to the wall thickness (5), the pipes are divided into:

especially thin-walled with D n /s more than 40 and pipes with a diameter of 20 mm or less with a wall of 0.5 mm or less;

thin-walled with D n /s from 12.5 to 40 and pipes with a diameter of 20 mm or less with a wall of 1.5 mm;

thick-walled at D H /s from 6 to 12.5;

especially thick-walled with D n / s less than 6.

3. Along the length of the pipe must be made:

random length from 1.5 to 11.5 m;

measured length from 4.5 to 9 m with maximum deviations along the length of +10 mm; by order of foreign trade organizations, pipes are manufactured with a measured length of 4 to 9 m with maximum deviations along the length of +10 mm;

length, a multiple of the measured length, from 1.5 to 9 m with an allowance for each cut of 5 mm (unless another allowance is specified in the order) and with maximum deviations for the total length not exceeding the measured length specified for pipes.

(Revised edition, Rev. No. 3).

4. Limit deviations in the outer diameter and wall thickness of pipes should not exceed those indicated in Table. 2.

5. By agreement between the manufacturer and the consumer, pipes can be manufactured with combined limit deviations, for example, in terms of outer diameter - increased accuracy according to GOST 9567, and in terms of wall thickness - normal accuracy, or with one-sided dimensional tolerance. The value of the value of one-sided tolerance should not exceed the sum of the two-sided limit deviations given in table. 2. In this case, the value of the theoretical mass of 1 m of pipes is calculated from the arithmetic mean of the sum of the plus and minus limit deviations given in Table. 2.

Official publication Reprint prohibited

Outer

Theoretical mass

kg, with wall thickness, mm

Extra thin-walled

Thin-walled

thick-walled

Extra thick-walled

GOST 8734-75 C.

Outer

) thick-walled

3 GOST 8734-75

GOST 8734-75 C.

Outer

Theoretical weight of 1 m of pipes, kg, with wall thickness, mm

diameter, mm

Extra thin-walled

Thin-walled

5 GOST 8734-75

Outer		Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
DI<ШС1р,
	Thin-walled

Outer

Theoretical weight of 1 m of pipes, kg, with wall thickness,

diameter, mm

Extra thick-walled

7 GOST 8734-75

Outer

Theoretical weight of 1 m of pipes, kg, with wall thickness, mm

Extra thin-walled

8,779 9,647 10,944

Sequel poppy 1

Outer

Theoretical weight of 1 m of pipes, kg, with wall thickness, mm

diameter, mm
	Extra thin-walled	Thin-walled

Continuation poppy

Outer

shchessh weight of 1 m of pipes, kg, with wall thickness, i

diameter, mm

thin-walled

thick-walled

Notes:

L The theoretical mass of 1 m of pipe length is calculated in kilograms using the formula:

M \u003d 0.0ShSh‘5 (O and -5),

; M - weight, kg; D h - outer diameter, mm; s - wall thickness, mm.

When determining the theoretical mass of 1 m of pipes, the steel density of 7.85 g/cm 3 is taken as the initial value.

GOST 8734-75 C.

2. At the request of the consumer, it is allowed to manufacture pipes with a diameter of 4 mm with a wall thickness of 0.2 to 1.2 mm, diameters of 125 and 133 mm with a wall thickness of 2.0 to 20 mm, as well as dimensions of 29x5.5; 32x8.5; 33x1.5; 33x8.0; 39x3.0; 41x5.5; 43x8.0; 44x3.0; 46x3.0; 46x6.0; 55x9.0; 58x4.0 and 84x8.0mm.

3. Pipes with a diameter of 100 mm or more with a D H /s ratio of more than 50 and pipes with a D H /s ratio of less than 4 are supplied according to the technical documentation agreed with the customer.

table 2

Limit deviations for the inner diameter of pipes should not exceed the corresponding limit deviations for the outer diameter.

For pipes with an inner diameter of 10 mm or less, the maximum deviations in the inner diameter are set by agreement between the manufacturer and the consumer.

7. The ovality and wall thickness of pipes should not take their dimensions beyond the limit deviations, respectively, in terms of the outer diameter and wall thickness.

8. The curvature of any section of the pipe per 1 m of length should not exceed;

3 mm - for pipes with a diameter of 4 to 8 mm;

2 mm - for pipes with a diameter of 8 to 10 mm;

1.5 mm - for pipes with a diameter of over 10 mm.

At the request of the consumer, the curvature of pipes with a diameter of 20-90 mm should not exceed 1 mm per 1 m of length.

(Revised edition, Rev. No. 2).

9. Pipe material and technical requirements for them - according to GOST 8733.

Legend Examples

Pipe with an outer diameter of 70 mm, a wall thickness of 2.0 mm, a length that is a multiple of 1250 mm, made of steel grade 20, supplied according to the chemical composition (according to group B) GOST 8733;

The same, 6000 mm long (measured length), made of grade 20 steel, supplied according to mechanical properties

70 ■2 ■ 1250 kr GOST 8734-75

B 20 GOST 8733-74

you and the chemical composition (according to group B) GOST 8733;

The same, with combined limit deviations (for the diameter of increased accuracy according to

702-6000 GOST 8734-75

B 20 GOST 8733-74

GOST 9567, according to the wall thickness of normal accuracy):

The same, random length, with delivery without rationing of mechanical properties and chemical

70 p-g6000 GOST 8734-75

B 20 GOST 8733-74

composition, but indicating the value of hydraulic pressure (for group D) GOST 8733:

The same, from steel grade 10, with delivery according to mechanical properties controlled by thermal

702 GOST 8734-75

D GOST 8733-74

ki processed samples, and by chemical composition (for group D) GOST 8733:

702 GOST 8734-75

G10 GOST 8733-74

Pipe with an inner diameter of 70 mm and a wall thickness of 2.5 mm of random length, made of steel grade 40X, delivery according to group B in accordance with GOST 8733:

D bh 702.5 GOST 8734-75

V 40HGOST 8733-74

INFORMATION DATA

1. APPROVED AND INTRODUCED BY Decree of the State Committee for Standards of the Council of Ministers of the USSR dated 13.10.75 No. 2604

2. REPLACE GOST 8734-58

3. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

4. Checked in 1991. The validity period was removed by the Decree of the State Standard of the USSR dated 11.11.91 No. 1714

5. EDITION (July 2007) with Amendments No. 1, 2, 3, approved in August 1978, November 1981, March 1988 (NUS 9-78, 2-82, 6-88)

Editor L.V. Afanasenko Technical editor O.N. Vlasova Proofreader A.S. Chernousova Computer proofing L.A. Circular

Signed for publication on 27.07.2007. Format 60x84 "/ 8. Offset paper. Headset Times. Offset printing. Large print sheet 1.40.

Uch.-ed. l. 1.20. Circulation 83 copies. Zach. 629.

FSUE "STANDARTINFORM", 123995 Moscow, Granatny per., 4.

Typed in FSUE "STANDARTINFORM" on a PC.

Printed in the branch of FSUE "STANDARTINFORM" - type. "Moscow printer", 105062 Moscow, Lyalin per., 6

GOST 8734-75

Group B62

INTERSTATE STANDARD

COLD-WORKED SEAMLESS STEEL PIPES

Assortment

Seamless steel tubes cold deformed.
Range

ISS 23.040.10
OKP 13 4400, 13 5100

Introduction date 1977-01-01

INFORMATION DATA

1. APPROVED AND PUT INTO EFFECT by the Decree of the State Committee of Standards of the Council of Ministers of the USSR dated 13.10.75 N 2604

2. REPLACE GOST 8734-58

3. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Item number
GOST 8733-74
GOST 9567-75

4. The limitation of the validity period was removed by the Decree of the State Standard of the USSR dated 11.11.91 N 1714

5. EDITION with Amendments No. 1, 2, 3, approved in August 1978, November 1981, March 1988 (IUS 9-78, 2-82, 6-88)

1a. This standard fully complies with ST SEV 1483-78.

(Introduced additionally, Rev. N 2).

1. The outer diameter, wall thickness and theoretical mass of pipes must correspond to those indicated in Table 1.

Table 1

Continuation of Table 1

Outside diameter,

Extra thick-walled

Continuation of Table 1

Outside diameter,

Theoretical weight of 1 m of pipes, kg, with wall thickness, mm

Extra thin-walled

Continuation of Table 1

Particularly thick-walled at less than 6.

3. Along the length of the pipe must be made:

Random length from 1.5 to 11.5 m;

Measured length from 4.5 to 9 m with maximum deviations along the length of +10 mm; by order of foreign trade organizations, pipes are manufactured with a measured length of 4 to 9 m with maximum deviations along the length of +10 mm;

Length, a multiple of measured length, from 1.5 to 9 m with an allowance for each cut of 5 mm (unless another allowance is specified in the order) and with maximum deviations for the total length not more than the measured length specified for pipes.

(Changed edition, Rev. N 3).

4. Limit deviations in the outer diameter and wall thickness of pipes should not exceed those indicated in Table 2.

5. By agreement between the manufacturer and the consumer, pipes can be manufactured with combined limit deviations, for example, in terms of outer diameter - increased accuracy according to GOST 9567, and in terms of wall thickness - normal accuracy, or with one-sided dimensional tolerance. The value of one-sided tolerance should not exceed the sum of the two-sided limit deviations given in Table 2. In this case, the value of the theoretical mass of 1 m of pipes is calculated by the arithmetic mean of the sum of the plus and minus limit deviations given in Table 2.

table 2

Pipe dimensions	Limit deviations
Outer diameter, mm:
from 4 to 10 incl.
over 10 "30"


Wall thickness, mm:

over 1 to 5 incl.
” 1 ” 2.5 with a diameter of 110 mm or more

4, 5. (Changed edition, Rev. N 2).

Limit deviations for the inner diameter of pipes should not exceed the corresponding limit deviations for the outer diameter.

For pipes with an inner diameter of 10 mm or less, the maximum deviations in the inner diameter are set by agreement between the manufacturer and the consumer.

7. The ovality and wall thickness of pipes should not take their dimensions beyond the limit deviations, respectively, in terms of the outer diameter and wall thickness.

8. The curvature of any section of the pipe per 1 m of length should not exceed:

3 mm - for pipes with a diameter of 4 to 8 mm;

2 mm - for pipes with a diameter of 8 to 10 mm;

1.5 mm - for pipes with a diameter of over 10 mm.

At the request of the consumer, the curvature of pipes with a diameter of 20-90 mm should not exceed 1 mm per 1 m of length.

Note. For pipes with a ratio of outer diameter to wall thickness equal to 50 or more, manufactured without heat treatment, the curvature standards are established by agreement between the manufacturer and the consumer.

(Changed edition, Rev. N 2).

9. Pipe material and technical requirements for them - according to GOST 8733.

Legend Examples

The same, 6000 mm long (measured length), made of grade 20 steel, delivered according to mechanical properties and chemical composition (according to group B) GOST 8733:

The same, with combined limit deviations (on the diameter of increased accuracy according to GOST 9567, on the wall thickness of normal accuracy):

The same, made of grade 10 steel, supplied according to mechanical properties, controlled on heat-treated samples, and according to chemical composition (according to group G) GOST 8733:

Pipe with an inner diameter of 70 mm and a wall thickness of 2.5 mm of random length, made of steel grade 40X, delivery according to group B in accordance with GOST 8733:

The text of the document is verified by:
official publication
Pipes metal and connecting parts to them.
Part 1. Smooth seamless pipes: Sat. GOSTs -
M.: IPK Standards Publishing House, 2004