GOST 10705 80 electric-welded steel pipes. Pipes are steel electrowelded. Tensile strength, MPa

30.11.2019

STATE STANDARD OF THE UNION OF THE SSR

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

GOST 10705-80

Standards Publishing House

Moscow

STATE STANDARD OF THE UNION OF THE SSR

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes.

The standard does not apply to steel pipes used for the manufacture of thermal electric heaters.

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704 -91

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

A - with standardization of mechanical properties from calm, semi-quiet and boiling steel grades St1, St2, St3, St4 according to GOST 380-94 (category 4 according to GOST 16523-89, category 4 according to GOST 14637-89);

B - with rationing of the chemical composition from calm, semi-calm and boiling steel grades St1 St2, St3, St4 in accordance with GOST 380-94 and GOST 14637-89, from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 in accordance with GOST 1050- 88, made of steel grade 08Yu according to GOST 9045

B - with standardization of mechanical properties and chemical composition of calm, semi-calm and boiling steel grades St1, St2, St3, St4 according to GOST 380-94 (category 4 according to GOST 16523-89 and category 2-5 according to GOST 14637-89), from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 according to GOST 1050-88, from steel grade 08Yu according to GOST 9045-93, from low-alloy steel grade 22GU with the chemical composition given in (pipes with a diameter of 140 to 426 mm) ;

D - with standardization of test hydraulic pressure.

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

2.3. Pipes are manufactured heat-treated (over the entire volume of the pipe or along a welded joint), hot-reduced and without heat treatment.

The type of heat treatment throughout the entire volume of the pipe is chosen by the manufacturer. By agreement between the manufacturer and the consumer, the pipes are thermally treated in a protective atmosphere.

Pipes made of steel grade 22GU are made heat-treated along the welded joint or throughout the volume, pipes made of steel grade St1 - without heat treatment.

(Changed edition, Rev. No. 1, Rev. No. 5).

2.4. Mechanical properties of the base metal of heat-treated and hot-reduced pipes made of carbon steels must comply with the standards specified in . The mechanical properties of heat-treated pipes made of steel grade 22GU are established by agreement of the parties.

steel grade	Tensile strength sv, N/mm2 (kgf/mm2)	Yield strength st N/mm2 (kgf/mm2)	Relative elongation d5, %
steel grade


08, 08ps, 10kp 10, 10ps, 15kp,		196 (20)
St2sp, St2kp, St2ps 1 5, 15ps, 20kp,
St3sp, St3ps, St3kp
St4sp, St4ps, St4kp,

(Changed edition, Rev. No. 2, Rev. No. 3, Rev. No. 4 Rev. No. 5).

2.5. Mechanical properties of the base metal of pipes with a diameter of 10 to 152 mm inclusive without heat treatment and with heat treatment welded joint must comply with the standards specified in Table. . The mechanical properties of the base metal of pipes with a diameter of more than 152 to 530 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in.

Steel grade	Temporary resistance rupture sv, N/mm2 (kgf/mm2), with the outer diameter of pipes D, mm	fluidity st, N/mm2 (kgf/mm2)	with outer diameter of pipes
			from 10 to 60 for wall thickness
			over 0.06 D	0,06 D and less
	at least

08ps, 08kp, St1ps, St1kp

10kp, St2kp
10ps, St2ps








St4kp, St4ps

Note. At the request of the consumer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation increases by 3% compared with the standards given in Table. .

Steel grade	wall thickness,	Temporary resistance break sv,	Yield strength st, N/mm2 (kgf/mm2)	Relative elongation ds, %, with outer diameter of pipes D, mm
				St. 152 to 244.5	St. 244.5 to 377	St. 377 to 530
	at least
08.08ps, 08kp
10, 10ps, 10kp, St2kp
St2sp, St2ps

15, 15ps, 15kp,
20, 20ps, 20kpp
St3sp, St3ps,

St4sp, St4ps,

	All thicknesses

(Revised edition, Rev. No. 1, Rev. No. 3, Rev. No. 4, Rev. No. 5).

2.6. . Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface.

Ripples, nicks, dents, small risks, a layer of scale and traces of stripping are allowed provided that they do not take the wall thickness and pipe diameter beyond the maximum deviations. Edge displacement up to 10% of the nominal wall thickness is allowed.

The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed.

Lack of penetration of seams must be welded, the place of welding is cleaned. By agreement with the consumer, on pipes with a diameter of 159 mm or more, in places where welds are repaired by welding, the offset of the welded edges is allowed no more than 20% of the nominal wall thickness and the height of the reinforcement bead is not more than 2.5 mm.

Repair by welding of the main metal of pipes is not allowed.

In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint).

(Changed edition, Rev. No. 1, Rev. No. 4, Rev. No. 5).

2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed.

By agreement between the manufacturer and the consumer, one transverse seam is allowed on pipes with a diameter of less than 57 mm.

2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance.

At the request of the consumer, on pipes with an internal diameter of 33 mm or more, the internal burr must be partially removed or flattened, while the height of the burr or its traces should not exceed 0.35 mm - with a wall thickness of less than 2 mm; 0.4 mm - with a wall thickness of 2 to 3 mm; 0.5 mm - with a wall thickness of more than 3 mm.

The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the consumer.

(Changed edition, Rev. No. 1, 3).

2.9. Pipe ends must be square cut and deburred. The formation of a chamfer is allowed. The oblique cut for pipes with a diameter of up to 219 mm should not exceed 1 mm, and for pipes with a diameter of 219 mm or more - 1.5 mm. By agreement between the manufacturer and the consumer, the pipes are made cut into the lines of the mill.

2.10. At the request of the consumer, the ends of pipes with a wall thickness of 5 mm or more must be chamfered at an angle of 25-30 ° to the end of the pipe and an end ring 1.8 mm ± 0.8 mm wide should be left. By agreement between the manufacturer and the consumer, the bevel angle and the width of the end ring can be changed.

2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, pipes are divided into two types:

I - pipes with a diameter of up to 102 mm - test pressure 6.0 MPa (60 kgf / cm2) and pipes with a diameter of 102 mm or more - test pressure 3.0 MPa (30 kgf / cm2);

II - pipes of groups A and B, supplied at the request of the consumer with a test hydraulic pressure calculated in accordance with GOST 3845-75, at an allowable stress equal to 90% of the standard yield strength for pipes made of this steel grade, but not exceeding 20 MPa (200 kgf /cm2).

(Changed edition, Rev. No. 3, Rev. No. 5).

2.12. Heat-treated pipes made of steel grades St3sp, St3ps (categories 3-5), 10, 15 and 20 with a wall thickness of at least 6 mm must withstand the impact bending test of the base metal. In this case, the impact strength standards must comply with those specified in.

(Changed edition, Rev. No. 1, Rev. No. 4, Rev. No. 5).

2.13. Heat-treated pipes with a diameter of up to 152 mm inclusive, hot-reduced and non-heat-treated pipes with a diameter of more than 20 to 152 mm inclusive and a wall thickness of 0.06 Dn and less, as well as pipes with heat treatment of a welded joint must pass the flattening test.

Flattening of heat-treated pipes should be carried out up to the distance between the flattening planes H, mm, calculated by the formula

where a- the coefficient for pipes made of steel grades 08Yu, 08kp, 8ps.08, 10kp, St2kp is 0.09, and for pipes made of other steel grades it is 0.08;

S - nominal wall thickness, mm;

Dn - nominal outer diameter of the pipe, mm.

Flattening of pipes without heat treatment should be carried out up to a distance equal to 2/3 Dн. Flattening of pipes with heat treatment of the welded joint should be carried out up to a distance equal to 1/2 Dн.

At the request of the consumer, flattening of heat-treated pipes with a diameter of more than 152 to 530 mm should be carried out to a distance equal to 2/3 Dн.

(Changed edition of Rev. No. 1, Rev. No. 3, Rev. No. 4, Rev. No. 5).

2.14. Pipes up to 108 mm in diameter must pass the expansion test.

Pipes without heat treatment with a diameter of up to 20 mm, as well as a diameter of 20-60 mm with a wall thickness of more than 0.06 DH are not tested for expansion.

Increasing the outer diameter of heat-treated. pipes during distribution must comply with the standards specified in.

The increase in the outer diameter of pipes without heat treatment during expansion should be at least 6%.

At the request of the consumer, the increase in the outer diameter during the distribution of heat-treated pipes with a wall thickness of up to 4 mm from steel grades 10kp, St2kp must be at least 12%.

(Changed edition, Rev. No. 1, 3, 4).

2.15. At the request of the consumer, the pipes must withstand the tests provided for in paragraphs. -

The temporary resistance of the welded joint of pipes with a diameter of 219 to 530 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must comply with the standards specified in. The tensile strength of the welded joint of pipes with a diameter of 50 to 203 mm that has undergone heat treatment over the entire volume of the pipe or heat treatment of the welded joint must be at least 0.9 of the standards specified in.

The tensile strength of the welded joint of pipes without heat treatment with a diameter of 50 mm or more must comply with the standards specified in Table. and .

2.19. Pipes must be sealed.

(Revised edition, Rev. No. 3).

3. ACCEPTANCE RULES

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, one steel grade, one type of heat treatment and one manufacturing group, accompanied by one quality document, in accordance with GOST 10692-80

with addition chemical composition steel in accordance with the document on the quality of the enterprise - the manufacturer of the workpiece.

The number of pipes in a batch should not exceed, pcs.:

1000 - with a diameter of up to 30 mm;

600 - with a diameter of St. 30 to 76 mm;

400 - with a diameter of St. 76 to 152 mm;

200 - with a diameter of St. 152 mm.

3.2. In case of disagreement in assessing the quality of the chemical composition, at least one pipe from the batch is selected for verification.

3.3. Each pipe is subjected to control of the dimensions and quality of the pipe surface. It is allowed to control the dimensions and surface selectively on each batch with a single-stage normal level of control in accordance with the requirements of GOST 18242-72. Control plans are established by agreement between the manufacturer and the consumer.

(Revised edition, Rev. No. 3).

3.3a. Welded seams of pipes of groups A, B and C must be subjected to 100% control by non-destructive methods.

When conducting non-destructive testing along the perimeter of the entire pipe, hydraulic testing of pipes of type I is allowed not to be carried out.

Instead of non-destructive testing of welded seams of type I pipes, it is allowed to test each pipe with increased hydraulic pressure calculated in accordance with the requirements of GOST 3845-75 at an allowable stress equal to 85% of the yield strength for pipes with a diameter of 273 mm and more and 75% of the yield strength for pipes with a diameter of less than 273 mm, but not exceeding 12 MPa (120 kgf / cm2).

Pipes of group D must be subjected to a hydraulic pressure test or control weld non-destructive methods.

(Introduced additionally, Rev. No. 3). (Revised edition, Rev. No. 5). (Amendment,).

3.4. To check the height of the internal burr, 2% of the pipes from the batch are selected.

3.5. For tests on flattening, expanding, beading, bending, impact strength, the tendency of the base metal of pipes to mechanical aging, stretching of the base metal and the weld, two pipes are taken from the batch.

The yield strength of the base metal of pipes is determined at the request of the consumer.

At the request of the consumer, the determination of impact strength is not carried out.

Pipes subjected to the flattening test are not subjected to the expansion test.

(Revised edition, Rev. No. 1).

3.6. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on it on a double number of pipes selected from the same batch.

The retest results apply to the entire lot.

3.7. Welding joints of pipes of groups A, B, C must be controlled by non-destructive methods, and repaired pipes are tested by hydraulic pressure in accordance with the requirements of clause 3.3a of this standard.

Welding joints of pipes of group D must be tested by non-destructive methods, or pipes after repair must be tested with hydraulic pressure.

(Introduced additionally, Rev. No. 1, Amended edition, Rev. No. 5).

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test, and for impact testing, three samples are cut for each test temperature.

4.2. The chemical composition of steel is determined according to GOST 22536.0 -87; GOST 22536.1-88; GOST 22536.2-87; GOST 22536.3-88; GOST 22536.4 -88; GOST 22536.5-87; GOST 22536.6 -88 GOST 12344-88; GOST 12345-88; GOST 12346-78; GOST 12347-77, GOST 12348-78; GOST 12349-83; GOST 12350-78; GOST 12351-81; GOST 12352-81; GOST 12353-78; GOST 12354-81. Samples for determining the chemical composition are taken according to GOST 7565-81.

4.3. Inspection of the surface of the pipes is carried out visually. The depth of defects is checked by sawing or in another way.

It is allowed to control the surface and dimensions of pipes by non-destructive methods according to technical documentation.

(Revised edition, Rev. No. 1).

4.4. Pipes measure:

length - tape measure but GOST 7502-89.

outer diameter and ovality - with an adjustable measuring bracket in accordance with GOST 2216-84 or a caliper in accordance with GOST 166-89 or a micrometer in accordance with GOST 6507-89 ;;

inner diameter - with a stopper in accordance with GOST 14810-69, or with a caliber in accordance with GOST 2015-84, or by subtracting two wall thicknesses from the outer diameter;

curvature - with a straightedge in accordance with GOST 8026-92 and a probe;

wall thickness, thickness difference and height of the internal burr - with a micrometer in accordance with GOST 6507 -90 or a wall gauge in accordance with GOST 11358 -89;

edge offset - with a template according to technical documentation or a micrometer in accordance with GOST 6507-90 or a depth gauge in accordance with GOST 162-90;

the cut oblique is provided by the design of the equipment for processing the ends of the pipes, the bevel angle of the chamfer is provided by the goniometer according to GOST 5378-88. In case of disagreement in assessing the quality of the cut, the cut is checked with a coal miner and a probe;

end ring at the ends of the pipes - with a ruler according to GOST 427 -75;

the depth of surface defects - with a depth gauge according to GOST 162-90. Measurement of the outer diameter of the pipe is carried out at a distance of at least 15 mm from the end of the pipe for pipes with a ratio of the outer diameter to the wall thickness D H/ S H equal to 35 or less; at a distance of at least 2/3 DH - for pipes with a ratio D H/ S H over 35 to 75; at a distance of at least DH - for pipes with ratio D H/ S H over 75.

(Changed edition, Rev. No. 1, 3).

4.5. The impact bending test is carried out on longitudinal samples of type 3 according to GOST 9454-78, cut from a pipe section located at an angle of about 90 ° to the weld.

Impact strength is determined as the arithmetic mean of the test results of three samples. On one of the samples, a decrease in impact strength by 9.8 104 J/m2 (1 kgf m/cm2) is allowed.

The temperature of the test for impact bending of pipes made of steel grades 08, 10, 15 and 20 is chosen by the consumer.

(Revised edition, Rev. No. 1).

4.6. The tendency of the base metal of pipes to mechanical aging is determined according to GOST 7268-82. Editing of samples by static load is allowed.

STATE STANDARD OF THE UNION OF THE SSR

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

GOST 10705-80

Standards Publishing House

Moscow

STATE STANDARD OF THE UNION OF THE SSR

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes.

The standard does not apply to steel pipes used for the manufacture of thermal electric heaters.

(Revised edition, Rev. No. 5).

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704 -91

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

B - with rationing of the chemical composition of calm, semi-calm and boiling steel grades St1 St2, St3, St4 according to GOST 380-94 and GOST 14637-89, from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 according to GOST 1050-88, from steel grade 08Yu according to GOST 9045

B - with standardization of mechanical properties and chemical composition of calm, semi-quiet and boiling steel grades St1, St2, St3, St4 according to GOST 380-94 (category 4 according to GOST 16523-89 and category 2-5 according to GOST 14637-89), from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 according to GOST 1050-88, from steel grade 08Yu according to GOST 9045-93, from low-alloy steel grade 22GU with a chemical composition given in (pipes with a diameter of 140 to 426 mm);

D - with standardization of test hydraulic pressure.

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

2.3. Pipes are manufactured heat-treated (over the entire volume of the pipe or along a welded joint), hot-reduced and without heat treatment.

Pipes made of steel grade 22GU are made heat-treated along the welded joint or throughout the volume, pipes made of steel grade St1 - without heat treatment.

2.4. The mechanical properties of the base metal of heat-treated and hot-reduced carbon steel pipes must comply with the standards specified in. The mechanical properties of heat-treated pipes made of steel grade 22GU are established by agreement of the parties.

2.5. The mechanical properties of the base metal of pipes with a diameter of 10 to 152 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. . The mechanical properties of the base metal of pipes with a diameter of more than 152 to 530 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in.

2.6. . Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface.

The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed.

Repair by welding of the main metal of pipes is not allowed.

In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint).

(Changed edition, Rev. No. 1, Rev. No. 4, Rev. No. 5).

2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed.

By agreement between the manufacturer and the consumer, one transverse seam is allowed on pipes with a diameter of less than 57 mm.

2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance.

The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the consumer.

(Changed edition, Rev. No. 1, 3).

2.10. At the request of the consumer, at the ends of pipes with a wall thickness of 5 mm or more, a chamfer must be removed at an angle of 25-30 ° to the end of the pipe and an end ring 1.8 mm wide should be left± 0.8 mm. By agreement between the manufacturer and the consumer, the bevel angle and the width of the end ring can be changed.

2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, pipes are divided into two types:

I - pipes with a diameter of up to 102 mm - test pressure 6.0 MPa (60 kgf / cm2) and pipes with a diameter of 102 mm or more - test pressure 3.0 MPa (30 kgf / cm2);

(Changed edition, Rev. No. 3, Rev. No. 5).

Flattening of heat-treated pipes should be carried out up to the distance between the flattening planes H, mm, calculated by the formula

,(1)

where a- the coefficient for pipes made of steel grades 08Yu, 08kp, 8ps.08, 10kp, St2kp is 0.09, and for pipes made of other steel grades it is 0.08;

S - nominal wall thickness, mm;

Dn - nominal outer diameter of the pipe, mm.

Flattening of pipes without heat treatment should be carried out up to a distance equal to 2/3 Dn. Flattening of pipes with heat treatment of the welded joint should be carried out up to a distance equal to 1/2 Dн.

At the request of the consumer, flattening of heat-treated pipes with a diameter of more than 152 to 530 mm should be carried out to a distance equal to 2/3 Dн.

(Changed edition of Rev. No. 1, Rev. No. 3, Rev. No. 4, Rev. No. 5).

2.14. Pipes up to 108 mm in diameter must pass the expansion test.

Pipes without heat treatment with a diameter of up to 20 mm, as well as a diameter of 20-60 mm with a wall thickness of more than 0.06 DH are not tested for expansion.

Increasing the outer diameter of heat-treated. pipes during distribution must comply with the standards specified in.

The increase in the outer diameter of pipes without heat treatment during expansion should be at least 6%.

(Changed edition, Rev. No. 1, 3, 4).

2.15. At the request of the consumer, the pipes must withstand the tests provided for in paragraphs. -

The temporary resistance of the welded joint of pipes with a diameter of 219 to 530 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must comply with the standards specified in . The tensile strength of the welded joint of pipes with a diameter of 50 to 203 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must be at least 0.9 of the norms specified in .

The tensile strength of the welded joint of pipes without heat treatment with a diameter of 50 mm or more must comply with the standards specified in Table. and .

2.19. Pipes must be sealed.

(Revised edition, Rev. No. 3).

3. ACCEPTANCE RULES

with the addition of the chemical composition of steel in accordance with the document on the quality of the enterprise - the manufacturer of the workpiece.

The number of pipes in a batch should not exceed, pcs.:

1000 - with a diameter of up to 30 mm;

600 - with a diameter of St. 30 to 76 mm;

400 - with a diameter of St. 76 to 152 mm;

200 - with a diameter of St. 152 mm.

3.2. In case of disagreement in assessing the quality of the chemical composition, at least one pipe from the batch is selected for verification.

(Revised edition, Rev. No. 3).

3.3a. Welded seams of pipes of groups A, B and C must be subjected to 100% control by non-destructive methods.

When conducting non-destructive testing along the perimeter of the entire pipe, hydraulic testing of pipes of the type I allowed not to.

Allowed instead of non-destructive testing of welded joints of pipes of the type I to test each pipe with increased hydraulic pressure calculated in accordance with the requirements of GOST 3845-75 at an allowable stress equal to 85% of the yield strength for pipes with a diameter of 273 mm or more and 75% of the yield strength for pipes with a diameter of less than 273 mm, but not exceeding 12 MPa (120 kgf / cm 2).

Group D pipes must be subjected to a hydraulic pressure test or weld inspection by non-destructive methods.

(Introduced additionally, Rev. No. 3). (Revised edition, Rev. No. 5). (Amendment,).

3.4. To check the height of the internal burr, 2% of the pipes from the batch are selected.

The yield strength of the base metal of pipes is determined at the request of the consumer.

At the request of the consumer, the determination of impact strength is not carried out.

Pipes subjected to the flattening test are not subjected to the expansion test.

(Revised edition, Rev. No. 1).

3.6. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on it on a double number of pipes selected from the same batch.

The retest results apply to the entire lot.

Welding joints of pipes of group D must be tested by non-destructive methods, or pipes after repair must be tested with hydraulic pressure.

(Introduced additionally, Rev. No. 1, Amended edition, Rev. No. 5).

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test, and for impact testing, three samples are cut for each test temperature.

4.3. Inspection of the surface of the pipes is carried out visually. The depth of defects is checked by sawing or in another way.

It is allowed to control the surface and dimensions of pipes by non-destructive methods according to technical documentation.

(Revised edition, Rev. No. 1).

4.4. Pipes measure:

length - tape measure but GOST 7502-89.

outer diameter and ovality - with an adjustable measuring bracket in accordance with GOST 2216-84 or a caliper in accordance with GOST 166-89 or a micrometer in accordance with GOST 6507-89 ;;

or a caliper according to GOST 166 -89, or a micrometer according to GOST 6507 -89;

inner diameter - with a stopper in accordance with GOST 14810-69, or with a caliber in accordance with GOST 2015-84, or by subtracting two wall thicknesses from the outer diameter;

curvature - with a straightedge in accordance with GOST 8026-92 and a probe;

wall thickness, thickness difference and height of the internal burr - with a micrometer in accordance with GOST 6507 -90 or a wall gauge in accordance with GOST 11358 -89;

edge offset - with a template according to technical documentation or a micrometer in accordance with GOST 6507-90 or a depth gauge in accordance with GOST 162-90;

end ring at the ends of the pipes - with a ruler according to GOST 427 -75;

the depth of surface defects - with a depth gauge according to GOST 162-90. Measurement of the outer diameter of the pipe is carried out at a distance of at least 15 mm from the end of the pipe for pipes with a ratio of the outer diameter to the wall thicknessD h/ S H , equal to 35 or less; at a distance of at least 2/3 D H - for pipes with ratioD h/ S H over 35 to 75; at a distance of at least D H - for pipes with ratioD h/ S H over 75.

(Changed edition, Rev. No. 1, 3).

4.5. The impact bending test is carried out on longitudinal samples of type 3 according to GOST 9454-78, cut from a pipe section located at an angle of about 90 ° to the weld.

Impact strength is determined as the arithmetic mean of the test results of three samples. On one of the samples, a decrease in impact strength by 9.8· 10 4 J / m 2 (1 kgf · m / cm 2).

The temperature of the test for impact bending of pipes made of steel grades 08, 10, 15 and 20 is chosen by the consumer.

(Revised edition, Rev. No. 1).

4.6. The tendency of the base metal of pipes to mechanical aging is determined according to GOST 7268-82. Editing of samples by static load is allowed.

4.7. The tensile test is carried out according to GOST 10006-80 on a longitudinal (in the form of a strip or pipe section) proportional short sample.

When testing on samples of a segmental section, the latter is cut out from a section located at an angle of about 90 ° to the weld, and is not straightened in the calculated part.

Instead of tensile testing, it is allowed to control the tensile strength, yield strength and relative elongation of pipes by non-destructive methods.

GOST 10705-80

UDC 669.14-462.2:621.791.7:006.354 Group B62

ELECTRIC WELDED STEEL PIPES

Specifications

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes.

The standard does not apply to steel pipes used for the manufacture of thermal electric heaters.

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with -91.

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

A - with standardization of mechanical properties from calm, semi-quiet and boiling steel grades St 1, St2, St3, St4 to -94 (categories 4 to -89, categories 1 to -89);

B - with rationing of the chemical composition from calm, semi-calm and boiling steel grades St1, St2, St3, St4 to -94 and -89, from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 to -88 and steel grade 08Yu -93, from low-alloy steel grade 22GU with the chemical composition given in table. 1a (pipes with a diameter of 140 to 426);

B - with standardization of mechanical properties and chemical composition from calm, semi-calm and boiling steel grades St1, St2, St3, St4 to -94 (category 4 according to GOST 16523-89 and categories 2-5 according to GOST 14637-89), from calm, semi-calm and boiling steel grades 08, 10, 15, 20 to -88, from steel grade 08Yu according to GOST 9045-93, from low-alloy steel grade 22GU with the chemical composition given in Table. 1a (pipes with a diameter of 140 to 426 mm);

D - with standardization of test hydraulic pressure.

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

2.3. Pipes are manufactured heat-treated (over the entire volume of the pipe or along a welded joint), hot-reduced and without heat treatment.

Pipes made of steel grade 22GU are made heat-treated along the welded joint or throughout the volume, pipes made of steel grade St1 - without heat treatment.

Table 1a

	Mass fraction of the element, %
steel grade		Manganese	Aluminum

(Changed edition, Rev. No. 1, 5)

2.4. The mechanical properties of the base metal of heat-treated and hot-reduced carbon steel pipes must comply with the standards specified in Table. 1. The mechanical properties of heat-treated pipes made of steel grade 22GU are established by agreement of the parties.

(Changed edition, Rev. No. 5)

Table 1

steel grade	Tensile strength s in, N / mm 2 (kgf / mm 2)	Yield strength s t N/mm 2 (kgf/mm 2)	Relative elongation d 5 %



08, 08ps, 10kp
10, 10ps, 15kp, St2sp, St2kp, St2ps
15, 15ps, 20kp, St3ps, St3sp, St3kp
20, 20ps, St4sp, St4ps, St4kp,

(Changed edition, Rev. No. 2, 3, 4, 5).

table 2

	Tensile strength s in, N / mm 2 (kgf / mm 2), with outer diameter of pipes D, mm	Yield strength, s t,	Relative elongation d 5,%, with the outer diameter of the pipes
steel grade			10 to 60 for wall thickness		St. 60 to 152
			more than 0.06D	0.06 D or less


St1ps, St1kp

10kp, St2kp
10ps, St2ps








St4kp, St4ps

Note. At the request of the consumer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation increases by 3% compared with the standards given in Table. 2.

(Changed edition, Rev. No. 5)

Table3

		Tensile strength s in,	Yield strength s t, N / mm 2	Relative elongation d 5,%, with a diameter
steel grade	walls, mm	N/mm 2 (kgf/mm 2)		over 152 to 244.5	over 244.5 to 377	over 377 to 530

08, 08ps, 08kp
10, 10ps, 10kp, St2kp
St2sp, St2ps

15, 15ps, 15kp,
20, 20ps, 20kp
St3sp, St3ps, St3kp

St4sp, St4ps, St4kp

	All thicknesses

(Changed edition, Rev. No. 1, 3, 4, 5).

2.5. The mechanical properties of the base metal of pipes with a diameter of 10 to 152 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 2. The mechanical properties of the base metal of pipes with a diameter of more than 152 to 530 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 3.

(Revised edition, Rev. No. 5).

2.6. Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface.

The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed.

Repair by welding of the main metal of pipes is not allowed.

In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint).

(Changed edition, Rev. No. 1, 4, 5).

2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed.

By agreement between the manufacturer and the consumer, one transverse seam is allowed on pipes with a diameter of less than 57 mm.

(Changed edition, Rev. No. 5)

2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance.

The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the consumer.

(Changed edition, Rev. No. 1, 3).

(Revised edition, Rev. No. 3).

2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, pipes are divided into two types:

I - pipes with a diameter of up to 102 mm - test pressure 6.0 MPa (60 kgf / cm 2) and pipes with a diameter of 102 mm or more - test pressure 3.0 MPa (30 kgf / cm 2);

II - pipes of groups A and B, supplied at the request of the consumer with a test hydraulic pressure calculated in accordance with GOST 3845-75, with an allowable stress equal to 90% of the standard yield strength for pipes made of this steel grade, but not exceeding 20 MPa (200 kgf / cm 2).

(Changed edition, Rev. No. 3, 5).

Part 1

INTERSTATE STANDARD

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

Official edition

Standartinform

UDC 669.14-462.2:621.791.7:006.354

Group B62

INTERSTATE STANDARD

ELECTRIC WELDED STEEL PIPES

Specifications

electrically welded steel tubes. Specifications

MKS 23.040.10 OKP 13 7300 13 8100 13 8300

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes.

The standard does not apply to steel pipes used for the manufacture of thermal electric heaters.

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704.

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

A - with rationing of mechanical properties from calm, semi-quiet and boiling steel grades St1, St2, St3, St4 according to GOST 380 (category 4 according to GOST 16523, category 1 according to GOST 14637);

B - with rationing of the chemical composition from calm, semi-calm and boiling steel grades St1, St2, St3, St4 according to GOST 380 and GOST 14637, from calm, semi-quiet and boiling steel grades 08, 10, 15 and 20 according to GOST 1050, from steel grade 08Yu according to GOST 9045, from low-alloy steel grade 22GU with the chemical composition given in Table. 1a (pipes with a diameter of 140 to 426 mm);

B - with normalization of mechanical properties and chemical composition from calm, semi-calm and boiling steel grades St1, St2, St3, St4 according to GOST 380 (category 4 according to GOST 16523 and categories 2-5 according to GOST 14637), from calm, semi-quiet and boiling steel grades 08, 10, 15, 20 according to GOST 1050, from steel 08Yu according to GOST 9045, from low-alloy steel grade 22GU with the chemical composition given in Table. 1a (pipes with a diameter of 140 to 426 mm);

D - with standardization of test hydraulic pressure.

2.3. Pipes are manufactured heat-treated (over the entire volume of the pipe or along a welded joint), hot-reduced and without heat treatment.

Pipes made of steel grade 22GU are made heat-treated along the welded joint or throughout the volume, pipes made of steel grade St1 - without heat treatment.

Official edition

Reprint prohibited

Standards Publishing House, 1981 5) STANDARTINFORM, 2005 5) STANDARTINFORM, 2008

Table 1a

Table 1

steel grade	steel grade	Tensile strength a b, N / mm 2 (kgf / mm 2)	Yield strength o t, N / mm 2 (kgf / mm 2)	Relative elongation 6 5 , %
steel grade	steel grade

	20kp, StZsp,
08, 08ps, Yukp	StZps, StZkp
10, Yups, 15kp,
St2sp, St2ps,	St4sp, St4ps,

Note. At the request of the consumer, pipes with a wall thickness of 4 mm or more from steel grades St3ps, 15, 15ps are manufactured with a yield strength of 235 N / mm 2 (24 kgf / mm 2), relative elongation of 23%; from steel grades St4sp, 20, 20ps - with a yield strength of 255 N / mm 2 (26 kgf / mm 2), relative elongation of 22%.

table 2

	Tensile strength o in, N / mm 2, (kgf / mm 2), with an outer diameter of pipes D, mm			Yield strength o t, N / mm 2, (kgf / mm 2)	Relative elongation 6 5 , pipe outer diameter D,		%>, at mm
steel grade					from 10 to 60 for wall thickness		St. 60 to 152
		St. 19 to 60	St. 60 to 152		more than 0.06D	0.06 D or less	St. 60 to 152


St1ps, St1kp

Yukp, St2kp
Yups, St2ps








St4kp, St4ps

Note. At the request of the consumer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation increases by 3% compared with the standards given in Table. 2.

Table 3

steel grade	Thickness, walls, mm	Tensile strength a b, N / mm 2 (kgf / mm 2)	Yield strength s t, N / mm 2 (kgf / mm 2)	Relative elongation 6 5 , %, with pipe diameter D, mm
		Tensile strength a b, N / mm 2 (kgf / mm 2)	Yield strength s t, N / mm 2 (kgf / mm 2)	St. 152 to 244.4	St. 244.5 to 377	St. 377 to 530

08, 08ps, 08kp
YuDOps, Yukp, St2kp
St2sp, St2ps
St2sp, St2ps
15, 15ps, 15kp, 20, 20ps, 20kp
15, 15ps, 15kp, 20, 20ps, 20kp
StZps, StZps, StZkp
StZps, StZps, StZkp
St4ps, St4ps, St4kp
St4ps, St4ps, St4kp
	All thicknesses

2.5. The mechanical properties of the base metal of pipes with a diameter of 10 to 152 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 2. The mechanical properties of the base metal of pipes with a diameter of more than 152 to 530 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 3.

2.6. Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface.

Ribbons, nicks, dents, small risks, a layer of scale and traces of stripping are allowed when

provided that they do not take the wall thickness and pipe diameter beyond the limit deviations. Edge displacement up to 10% of the nominal wall thickness is allowed.

The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed.

Repair by welding of the main metal of pipes is not allowed.

In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint).

2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed.

By agreement between the manufacturer and the consumer, one transverse seam is allowed on pipes with a diameter of less than 57 mm.

2.2-2.7. (Revised edition, Rev. No. 5).

2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance.

The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the consumer.

2.9. Pipe ends must be square cut and deburred. Tolerance

the formation of a chamfer is repented. The oblique cut for pipes with a diameter of up to 219 mm should not exceed 1 mm, and for pipes with a diameter of 219 mm or more - 1.5 mm. By agreement between the manufacturer and the consumer, the pipes are made cut into the lines of the mill.

2.10. At the request of the consumer, at the ends of pipes with a wall thickness of 5 mm or more, a chamfer must be chamfered at an angle of 25 ° -30 ° to the end of the pipe and an end ring with a width of (1.8 ± 0.8) mm should be left. By agreement between the manufacturer and the consumer, the bevel angle and the width of the end ring can be changed.

2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, pipes are divided into two types:

I - pipes with a diameter of up to 102 mm - test pressure 6.0 MPa (60 kgf / cm 2) and pipes with a diameter of 102 mm or more - test pressure 3.0 MPa (30 kgf / cm 2);

II - pipes of groups A and B, supplied at the request of the consumer with a test hydraulic pressure calculated in accordance with GOST 3845, at an allowable stress equal to 90% of the normative yield strength for pipes made of this steel grade, but not exceeding 20 MPa (200 kgf / cm 2).

2.12. Heat-treated pipes made of steel grades St3sp, St3ps (categories 3-5), 10, 15 and 20 with a wall thickness of at least 6 mm must withstand the impact bending test of the base metal. In this case, the norms of impact strength must correspond to those indicated in Table. four.

Table 4

2.13. Heat-treated pipes with a diameter of up to 152 mm inclusive, hot-reduced pipes and without heat treatment with a diameter of more than 20 to 152 mm inclusive and a wall thickness of 0.06 Z) H and less, as well as pipes with heat treatment of the welded joint must withstand the flattening test.

Flattening of heat-treated pipes should be carried out up to the distance between the flattening planes H, mm, calculated by the formula

(1 + a) ■ s s

where a is the coefficient for pipes made of steel grades 08Yu, 08kp, 8ps, 08, Yukp, St2kp is 0.09, and for pipes made of other steel grades it is 0.08; s - nominal wall thickness, mm;

Z) H - nominal outer diameter of the pipe, mm.

Flattening of pipes without heat treatment should be carried out up to a distance equal to 2/3 D H . Flattening of pipes with heat treatment of the welded joint should be carried out up to a distance equal to 1/2 Z) H.

At the request of the consumer, flattening of heat-treated pipes with a diameter of more than 152 to 530 mm should be carried out to a distance equal to 2/3 Z) H.

2.11-2.13. (Revised edition, Rev. No. 5).

2.14. Pipes up to 108 mm in diameter must pass the expansion test.

Pipes without heat treatment with a diameter of up to 20 mm, as well as a diameter of 20-60 mm with a wall thickness of more than 0.06 Z) H are not tested for expansion.

The increase in the outer diameter of heat-treated pipes during expansion must comply with the standards specified in Table. 5.

Table 5

The increase in the outer diameter of pipes without heat treatment during expansion should be at least 6%.

At the request of the consumer, the increase in the outer diameter during the distribution of heat-treated pipes with a wall thickness of up to 4 mm from steel grades Yukp, St2kp must be at least 12%.

(Changed edition, Rev. No. 1, 3, 4).

2.15. At the request of the consumer, the pipes must withstand the tests provided for in paragraphs. 2.16-2.18.

2.16. Heat-treated pipes up to and including 530 mm in diameter must pass the bend test. The value of the bend radius for pipes with a diameter of up to 60 mm must be at least 2.5 A "for the base metal of pipes with a diameter of more than 60 to 530 mm - in accordance with GOST 3728. By agreement between the manufacturer and the consumer, the value of the bend radius can be reduced.

2.17. Heat-treated pipes with a diameter of 30 to 159 mm with a D / s ratio equal to

12.5 and above must pass the flight test. The width of the bent side, measured from the inner surface, must be at least 12% of the inner diameter of the pipe and not less than

1.5 wall thickness.

The angle of the flanging should be:

90 ° - for pipes made of steel grades 08, 10, 15, St2;

60 ° - for pipes made of steel grades 20, StZ, St4.

2.18. Pipes with a diameter of 50 mm or more of groups A and B must withstand the tensile test of the welded joint.

The temporary resistance of the welded joint of pipes with a diameter of 219 to 530 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must comply with the standards specified in Table. 1. The tensile strength of the welded joint of pipes with a diameter of 50 to 203 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must be at least 0.9 of the norms specified in Table. one.

The tensile strength of the welded joint of pipes without heat treatment with a diameter of 50 mm or more must comply with the standards specified in Table. 2 and 3.

(Revised edition, Rev. 1.3).

2.19. Pipes must be sealed.

(Revised edition, Rev. No. 3).

3. ACCEPTANCE RULES

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, one steel grade, one type of heat treatment and one production group, accompanied by one quality document, in accordance with GOST 10692 with the addition - the chemical composition of steel in accordance with the document on the quality of the enterprise - the manufacturer of the billet.

The number of pipes in a batch should not exceed, pcs.:

1000 - with a diameter of up to 30 mm;

600 - with a diameter of St. 30 to 76 mm;

400 - with a diameter of St. 76 to 152 mm;

200 - with a diameter of St. 152 mm.

(Revised edition, Rev. No. 1).

3.2. In case of disagreement in assessing the quality of the chemical composition, at least one pipe from the batch is selected for verification.

3.3. Each pipe is subjected to control of the dimensions and quality of the pipe surface. It is allowed to control the dimensions and surface selectively on each batch with a single-stage

normal level of control in accordance with the requirements of GOST 18242*. Control plans are established by agreement between the manufacturer and the consumer.

(Revised edition, Rev. No. 3).

**3.3a. Welded seams of pipes of groups A, B and C must be subjected to 100% control by non-destructive methods.

When conducting non-destructive testing along the perimeter of the entire pipe, hydraulic testing of type I pipes is allowed not to be carried out.

Instead of non-destructive testing of welded seams of type I pipes, it is allowed to test each pipe with increased hydraulic pressure calculated in accordance with the requirements of GOST 3845 at an allowable stress equal to 85% of the yield strength for pipes with a diameter of 273 mm and more and 75% of the yield strength for pipes with a diameter less than 273 mm, but not exceeding 12 MPa (120 kgf / cm 2).

Group D pipes must be subjected to a hydraulic pressure test or weld inspection by non-destructive methods.

(Revised edition, Rev. No. 5, Amendment).

When quality control of the weld by non-destructive methods is carried out, additional control is carried out by hydraulic pressure on 15% of the pipes from the batch.

By agreement between the manufacturer and the consumer, hydraulic pressure testing of pipes is not carried out.

(Introduced additionally, Rev. No. 3).

3.4. To check the height of the internal burr, 2% of the pipes from the batch are selected.

The yield strength of the base metal of pipes is determined at the request of the consumer.

At the request of the consumer, the determination of impact strength is not carried out.

Pipes subjected to the flattening test are not subjected to the expansion test.

(Revised edition, Rev. No. 1).

3.6. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on it on a double number of pipes selected from the same batch.

The retest results apply to the entire lot.

Welding joints of pipes of group D must be tested by non-destructive methods, or pipes after repair must be tested with hydraulic pressure.

(Revised edition, Rev. No. 5).

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test, and for impact testing, three samples are cut for each test temperature.

4.2. The chemical composition of steel is determined according to GOST 22536.0 - GOST 22536.6, GOST 12344 - GOST 12354. Samples for determining the chemical composition are taken according to GOST 7565.

4.3. Inspection of the surface of the pipes is carried out visually. The depth of defects is checked by sawing or in another way.

It is allowed to control the surface and size of pipes by non-destructive methods according to technical documentation.

(Revised edition, Rev. No. 1).

4.4. Pipes measure:

length - tape measure according to GOST 7502;

outer diameter and ovality - with an adjustable measuring clamp according to GOST 2216 or a caliper according to GOST 166, or a micrometer according to GOST 6507;

* Within the territory of Russian Federation GOST R 50779.71-99** applies.

inner diameter - with a stopper in accordance with GOST 14810 or with a caliber in accordance with GOST 2015, or by subtracting two wall thicknesses from the outer diameter;

curvature - with a straightedge according to GOST 8026 and a probe;

wall thickness, difference in wall thickness and height of the internal burr - with a micrometer according to GOST 6507 or a wall gauge according to GOST 11358;

edge offset - with a template according to technical documentation or a micrometer according to GOST 6507, or a depth gauge according to GOST 162;

cut oblique - the parameter is provided by the design of equipment for end processing

chamfer bevel angle - goniometer according to GOST 5378. In case of disagreement in assessing the quality, the cut bevel is checked with a square and a probe;

end ring at the ends of pipes - with a ruler according to GOST 427;

the depth of surface defects - with a depth gauge according to GOST 162. Measurement of the outer diameter of the pipe is carried out at a distance of at least 15 mm from the end of the pipe for pipes with a ratio of the outer diameter to the wall thickness Z) H /s H equal to 35 or less; at a distance of at least 2 / z Ai - for pipes with a ratio of D u / s u over 35 to 75; at a distance of at least D, - for pipes with a ratio of D H / s H over 75.

(Changed edition, Rev. No. 1, 3).

4.5. The impact test is carried out on longitudinal samples of type 3 according to GOST 9454, cut from a section of the pipe located at an angle of about 90 ° to the weld.

Impact strength is determined as the arithmetic mean of the test results of three samples. On one of the samples, a decrease in impact strength by 9.8 10 4 J / m 2 (1 kgf m / cm 2) is allowed.

The temperature of the test for impact bending of pipes made of steel grades 08, 10, 15 and 20 is chosen by the consumer.

(Revised edition, Rev. No. 1).

4.6. The tendency of the base metal of pipes to mechanical aging is determined according to GOST 7268. It is allowed to straighten the samples with a static load.

4.7. The tensile test is carried out according to GOST 10006 on a longitudinal (in the form of a strip or pipe section) proportional short sample.

When testing on samples of a segmental section, the latter is cut out from a section located at an angle of about 90 ° to the weld, and is not straightened in the calculated part.

Instead of tensile testing, it is allowed to control the tensile strength, yield strength and relative elongation of pipes by non-destructive methods.

In case of disagreement, pipes are tested in accordance with GOST 10006.

(Revised edition, Rev. No. 1).

4.8. The flattening test is carried out according to GOST 8695.

4.9. The expansion test is carried out according to GOST 8694 on a mandrel with a taper of 30 °. It is allowed to use mandrels with a taper of 1: 10 and to remove the burr in the distribution area.

(Revised edition, Rev. No. 3).

4.10. The bend test is carried out according to GOST 3728. Pipes with a diameter of 114 mm are tested on cut longitudinal strips 12 mm wide.

4.11. The beading test is carried out in accordance with GOST 8693. Burr removal is allowed in the flanging area.

4.12. Determination of the temporary resistance of a welded joint of pipes with a diameter of 50-530 mm is carried out on ring samples according to technical documentation.

On pipes with a diameter of 219 mm or more, it is allowed to test in accordance with GOST 6996 on samples of type XII with removed reinforcement of the welded joint, cut perpendicular to the pipe axis, using a static load when straightening the samples.

4.13. Hydraulic testing of pipes is carried out in accordance with GOST 3845 with holding under pressure for 5 s.

4.14. The control of the weld is carried out by non-destructive methods (ultrasonic, eddy current, magnetic or x-ray equivalent method) according to the technical documentation.

5. MARKING, PACKAGING, TRANSPORT AND STORAGE

5.1. Marking, packaging, transportation and storage - according to GOST 10692.

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of Ferrous Metallurgy of the USSR

2. APPROVED AND INTRODUCED BY Decree of the USSR State Committee for Standards dated December 25, 1980 No. 5970

Amendment No. 5 was adopted by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 13 dated 05/28/98)

Registered by the Technical Secretariat of the IGU No. 3166 The following voted for the adoption of the change:

State name	Name of the national standardization body
The Republic of Azerbaijan	Azgosstandart
Republic of Armenia	Armstate standard
Republic of Belarus	State Standard of the Republic of Belarus
The Republic of Kazakhstan	State Standard of the Republic of Kazakhstan
Republic of Kyrgyzstan	Kyrgyzstandart
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
The Republic of Tajikistan	T adjikgosstandart
Turkmenistan	Main State Inspectorate "Turkmenstandartlary"
	State Standard of Ukraine

3. REPLACE GOST 10705-63

4. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Item number		Item number
		GOST 11358-89
		GOST 12344-2003
GOST 380-94*		GOST 12345-2001
		GOST 12346-78
GOST 1050-88		GOST 12347-77
GOST 2015-84		GOST 12348-78
GOST 2216-84		GOST 12349-83
GOST 3728-78		GOST 12350-78
GOST 3845-75	2.11; 3.3a; 4.13	GOST 12351-2003
GOST 5378-88		GOST 12352-81
GOST 6507-90		GOST 12353-78
GOST 6996-66		GOST 12354-81
GOST 7268-82		GOST 14637-89
GOST 7502-98		GOST 14810-69
GOST 7565-81		GOST 16523-97
GOST 8026-92		GOST 18242-72*
GOST 8693-80		GOST 22536.0-87
GOST 8694-75		GOST 22536.1-88
GOST 8695-75		GOST 22536.2-87
GOST 9045-93		GOST 22536.3-88
GOST 9454-78		GOST 22536.4-88
GOST 10006-80		GOST 22536.5-87
GOST 10692-80		GOST 22536.6-88
GOST 10704-91

5. The limitation of the validity period was removed by the Decree of the State Standard of July 12, 1991 No. 1247

6. EDITION (November 2005) with Amendments No. 1, 2, 3, 4, 5 approved in December 1986, December 1987, June 1989, July 1991, April 1999 (IUS 2-87, 3-88, 10-89, 10-91, 7-99); Amendment (NUS 5-2005)

Reissue (as of March 2008).

See the notes of FSUE "STANDARTINFORM" (p. 9).

FSUE "STANDARTINFORM" NOTES

1 Specified in the section "Information data" to GOST 10705-80:

GOST 380-94 replaced by GOST 380-2005;

GOST 18242-72 has been replaced by GOST R ISO 2859-1-2007.

2 An amendment was published in the information index "National Standards" No. 5-2005

to GOST 10705-80 Electric-welded steel pipes. Specifications [see Edition (June 2001) with Amendments No. 1, 2, 3, 4, 5 and the collection “Metal pipes and fittings to them. Part 3. Welded pipes. Profile pipes "(Edition 2001)]

Editor R.G. Goverdovskaya Technical editor V.N. Prusakova Proofreader V.I. Barentseva Computer layout I.A. Naleykina

Signed for publication on April 29, 2008. Format 60 x 84 1/s. Offset paper. Headset Times. Offset printing. Uel. pech.l. 1.40. Uch.-ed.l. 1.10. Circulation 97 copies. Zach. 428.

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.

STATE STANDARD OF THE UNION OF THE SSR

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

GOST 10705-80

Standards Publishing House

Moscow

STATE STANDARD OF THE UNION OF THE SSR

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes.

The standard does not apply to steel pipesused for the manufacture of thermal electric heaters.

(Revised edition, Rev. No. 5).

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704 -91

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

On pipes with a diameter of 219 mm or more, it is allowed to test in accordance with GOST 6996-66 on specimens of type XII with removed reinforcement of the welded joint, cut perpendicular to the axis of the pipe, using a static load when straightening the specimens.

4.13. Hydraulic testing of pipes is carried out in accordance with GOST 3845 -75 with exposure under pressure for 5 s.

4.14. The control of the weld is carried out by non-destructive methods (ultrasonic, eddy current, magnetic or x-ray equivalent method) according to the technical documentation.

5.1. Marking, packaging, transportation and storage in accordance with GOST 10692-80. -89 -88 -72 -88 -91

5. REPUBLICATION (June 1993) with Amendments No. 1, 2, 3, 4 approved in December 1986, December 1987, June 1989, July 1991; May 1999 (IUS 2-7, 3-8, 10-9, 10-1; 7-1999). Amendment (IUS 5-2005)

STATE STANDARD OF THE UNION OF THE SSR

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

GOST 10705-80

Standards Publishing House

STATE STANDARD OF THE UNION OF THE SSR

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 530 mm made of carbon and low-alloy steel used for pipelines and structures for various purposes. The standard does not apply to steel pipes used for the manufacture of thermal electric heaters. (Revised edition, Rev. No. 5).

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704-91

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner. 2.2. Depending on the quality indicators, the pipes are manufactured in the following groups: A - with normalization of mechanical properties from calm, semi-quiet and boiling steel grades St1, St2, St3, St4 according to GOST 380-94 (category 4 according to GOST 16523-89, category 4 according to GOST 14637 -89); B - with rationing of the chemical composition from calm, semi-calm and boiling steel grades St1 St2, St3, St4 in accordance with GOST 380-94 and GOST 14637-89, from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 in accordance with GOST 1050- 88, from steel grade 08Yu according to GOST 9045-93, from low-alloy steel grade 22GU with the chemical composition given in Table. 1a (pipes with a diameter of 140 to 426 mm); B - with normalization of mechanical properties and chemical composition of calm, semi-quiet and boiling steel grades St1, St2, St3, St4 in accordance with GOST 380-94 (category 4 in accordance with GOST 16523-89 and category 2-5 in accordance with GOST 14637-89), from calm, semi-calm and boiling steel grades 08, 10, 15 and 20 according to GOST 1050-88, from steel grade 08Yu according to GOST 9045-93, from low-alloy steel grade 22GU with the chemical composition given in Table. 1a (pipes with a diameter of 140 to 426 mm); D - with standardization of test hydraulic pressure. (Changed edition, Rev. No. 4, Rev. No. 5). 2.3. Pipes are manufactured heat-treated (over the entire volume of the pipe or along a welded joint), hot-reduced and without heat treatment. The type of heat treatment throughout the entire volume of the pipe is chosen by the manufacturer. By agreement between the manufacturer and the consumer, the pipes are thermally treated in a protective atmosphere. Pipes made of steel grade 22GU are made heat-treated along the welded joint or throughout the volume, pipes made of steel grade St1 - without heat treatment.

Table 1a

(Changed edition, Rev. No. 1, Rev. No. 5). 2.4. The mechanical properties of the base metal of heat-treated and hot-reduced carbon steel pipes must comply with the standards specified in Table. 1. The mechanical properties of heat-treated pipes made of steel grade 22GU are established by agreement of the parties.

Table 1

Tensile strength s in, N / mm 2 (kgf / mm 2)

Yield strength s t

N/mm 2 (kgf/mm 2)

Relative elongation d 5 %

steel grade
steel grade
08Yu
08kp
08, 08ps, 10kp 10, 10ps, 15kp,
St2sp, St2kp, St2ps 1 5, 15ps, 20kp,
St3sp, St3ps, St3kp 20, 20ps,
St4sp, St4ps, St4kp,

Note. At the request of the consumer, pipes with a wall thickness of 4 mm or more from steel grades St3sp, 15, 15ps are manufactured with a yield strength of 235 N / mm 2 (24 kgf / mm 2), relative elongation of 23%; from steel grades St4sp, 20, 20ps - with a yield strength of 255 N / mm 2 (26 kgf / mm 2), a relative elongation of 22%. (Changed edition, Rev. No. 2, Rev. No. 3, Rev. No. 4 Rev. No. 5). 2.5. The mechanical properties of the base metal of pipes with a diameter of 10 to 152 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 2. The mechanical properties of the base metal of pipes with a diameter of more than 152 to 530 mm inclusive without heat treatment and with heat treatment of the welded joint must comply with the standards specified in Table. 3.

table 2

Steel grade	Temporary resistance gap s in, N / mm 2 (kgf / mm 2), with an outer diameter of pipes D, mm	fluidity s t, N/mm 2 (kgf/mm 2)	with outer diameter of pipes
			from 10 to 60 for wall thickness
			more than 0.06D	0.06 D or less
	at least
08Yu
08ps, 08kp, St1ps, St1kp
08, St1sp
10kp, St2kp
10ps, St2ps
10, St2sp
15kp
15ps, 20kp
15, 20ps
20
St3kp
St3ps
St3sp
St4kp, St4ps
St4sp
22GU

Note. At the request of the consumer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation increases by 3% compared with the standards given in Table. 2.

Table 3

Steel grade	wall thickness,	Temporary resistance break s in, (kgf / mm 2),	Yield strength s t, N / mm 2 (kgf / mm 2)	Relative elongation d s , %, with outer diameter of pipes D, mm
				St. 152 to 244.5	St. 244.5 to 377	St. 377 to 530
	at least
08.08ps, 08kp	6 or less
10, 10ps, 10kp, St2kp	More than 6
St2sp, St2ps	6 or less
	More than 6
15, 15ps, 15kp,	6 or less
20, 20ps, 20kpp	More than 6
St3sp, St3ps,	6 or less
St3kp	More than 6
St4sp, St4ps,	6 or less
St4kp	More than 6
22GU	All thicknesses

(Revised edition, Rev. No. 1, Rev. No. 3, Rev. No. 4, Rev. No. 5). 2.6. . Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface. Ripples, nicks, dents, small risks, a layer of scale and traces of stripping are allowed provided that they do not take the wall thickness and pipe diameter beyond the maximum deviations. Edge displacement up to 10% of the nominal wall thickness is allowed. The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed. Lack of penetration of seams must be welded, the place of welding is cleaned. By agreement with the consumer, on pipes with a diameter of 159 mm or more, in places where welds are repaired by welding, the offset of the welded edges is allowed no more than 20% of the nominal wall thickness and the height of the reinforcement bead is not more than 2.5 mm. Repair by welding of the main metal of pipes is not allowed. In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint). (Changed edition, Rev. No. 1, Rev. No. 4, Rev. No. 5). 2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed. By agreement between the manufacturer and the consumer, one transverse seam is allowed on pipes with a diameter of less than 57 mm. 2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance. At the request of the consumer, on pipes with an internal diameter of 33 mm or more, the internal burr must be partially removed or flattened, while the height of the burr or its traces should not exceed 0.35 mm - with a wall thickness of less than 2 mm; 0.4 mm - with a wall thickness of 2 to 3 mm; 0.5 mm - with a wall thickness of more than 3 mm. The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the consumer. (Changed edition, Rev. No. 1, 3). 2.9. Pipe ends must be square cut and deburred. The formation of a chamfer is allowed. The oblique cut for pipes with a diameter of up to 219 mm should not exceed 1 mm, and for pipes with a diameter of 219 mm or more - 1.5 mm. By agreement between the manufacturer and the consumer, the pipes are made cut into the lines of the mill. (Revised edition, Rev. No. 3). 2.10. At the request of the consumer, the ends of pipes with a wall thickness of 5 mm or more must be chamfered at an angle of 25-30 ° to the end of the pipe and an end ring 1.8 mm ± 0.8 mm wide should be left. By agreement between the manufacturer and the consumer, the bevel angle and the width of the end ring can be changed. 2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, the pipes are divided into two types: I - pipes with a diameter of up to 102 mm - a test pressure of 6.0 MPa (60 kgf / cm2) and pipes with a diameter of 102 mm or more - a test pressure of 3.0 MPa (30 kgf / cm2) cm2); II - pipes of groups A and B, supplied at the request of the consumer with a test hydraulic pressure calculated in accordance with GOST 3845-75, at an allowable stress equal to 90% of the standard yield strength for pipes made of this steel grade, but not exceeding 20 MPa (200 kgf / cm 2). (Changed edition, Rev. No. 3, Rev. No. 5). 2.12. Heat-treated pipes made of steel grades St3sp, St3ps (categories 3-5), 10, 15 and 20 with a wall thickness of at least 6 mm must withstand the impact bending test of the base metal. In this case, the norms of impact strength must correspond to those indicated in Table. four.

Table 4

The test for impact bending of the base metal of heat-treated pipes made of steel grade 22GU is carried out at the request of the consumer, the impact strength standards are set by agreement of the parties. (Changed edition, Rev. No. 1, Rev. No. 4, Rev. No. 5). 2.13. Heat-treated pipes with a diameter of up to 152 mm inclusive, hot-reduced and non-heat-treated pipes with a diameter of more than 20 to 152 mm inclusive and a wall thickness of 0.06 Dn and less, as well as pipes with heat treatment of a welded joint must pass the flattening test. Flattening of heat-treated pipes should be carried out up to the distance between the flattening planes H, mm, calculated by the formula

Where a is the coefficient for pipes made of steel grades 08Yu, 08kp, 8ps.08, 10kp, St2kp is 0.09, and for pipes made of other steel grades it is 0.08; S - nominal wall thickness, mm; Dn - nominal outer diameter of the pipe, mm. Flattening of pipes without heat treatment should be carried out up to a distance equal to 2/3 Dn. Flattening of pipes with heat treatment of the welded joint should be carried out up to a distance equal to 1/2 Dн. At the request of the consumer, flattening of heat-treated pipes with a diameter of more than 152 to 530 mm should be carried out to a distance equal to 2/3 Dн. (Changed edition of Rev. No. 1, Rev. No. 3, Rev. No. 4, Rev. No. 5). 2.14. Pipes up to 108 mm in diameter must pass the expansion test. Pipes without heat treatment with a diameter of up to 20 mm, as well as a diameter of 20-60 mm with a wall thickness of more than 0.06 DH are not tested for expansion. Increasing the outer diameter of heat-treated. pipes during distribution must comply with the standards specified in Table. 5.

Table 5

The increase in the outer diameter of pipes without heat treatment during expansion should be at least 6%. At the request of the consumer, the increase in the outer diameter during the distribution of heat-treated pipes with a wall thickness of up to 4 mm from steel grades 10kp, St2kp must be at least 12%. (Changed edition, Rev. No. 1, 3, 4). 2.15. At the request of the consumer, the pipes must withstand the tests provided for in paragraphs. 2.16- 2.18 2.16. Heat-treated pipes up to and including 530 mm in diameter must pass the bend test. The value of the bend radius for pipes with a diameter of up to 60 mm must be at least 2.5 D N, for the base metal of pipes with a diameter of more than 60 to 530 mm in accordance with GOST 3728-78, upon agreement between the manufacturer and the consumer, the value of the bend radius can be reduced. (Revised edition, Rev. No. 1). 2.17. Heat-treated pipes with a diameter of 30 to 159 mm with a D / s ratio of 12.5 or more must pass the beading test. The width of the bent side, measured from the inner surface, must be at least 12% of the inner diameter of the pipe and at least 1.5 wall thickness. The flanging angle should be: 90 ° - for pipes made of steel grades 08, 10, 15, St2; 60 ° - for pipes made of steel grades 20, St3, St4. 2.18. Pipes with a diameter of 50 mm or more of groups A and B must withstand a tensile test of a welded joint. The temporary resistance of the welded joint of pipes with a diameter of 219 to 530 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must comply with the standards specified in Table. one . The temporary resistance of the welded joint of pipes with a diameter of 50 to 203 mm, which have undergone heat treatment throughout the entire volume of the pipe or heat treatment of the welded joint, must be at least 0.9 of the norms indicated in Table. one . The tensile strength of the welded joint of pipes without heat treatment with a diameter of 50 mm or more must comply with the standards specified in Table. 2 and 3. (Changed edition, Rev. No. 1, 3). 2.19. Pipes must be sealed. (Revised edition, Rev. No. 3).

3. ACCEPTANCE RULES

3.1. Pipes are accepted in batches. The batch should consist of pipes of the same size, one steel grade, one type of heat treatment and one production group, accompanied by one quality document, in accordance with GOST 10692-80, with the addition of the chemical composition of steel in accordance with the quality document of the enterprise - the manufacturer of the workpiece. The number of pipes in a batch should be no more than, pcs.: 1000 - with a diameter of up to 30 mm; 600 - with a diameter of St. 30 to 76 mm; 400 - with a diameter of St. 76 to 152 mm; 200 - with a diameter of St. 152 mm. (Revised edition, Rev. No. 1). 3.2. In case of disagreement in assessing the quality of the chemical composition, at least one pipe from the batch is selected for verification. 3.3. Each pipe is subjected to control of the dimensions and quality of the pipe surface. It is allowed to control the dimensions and surface selectively on each batch with a single-stage normal level of control in accordance with the requirements of GOST 18242-72. Control plans are established by agreement between the manufacturer and the consumer. (Revised edition, Rev. No. 3). 3.3a. Welded seams of pipes of groups A, B and C must be subjected to 100% control by non-destructive methods. When conducting non-destructive testing along the perimeter of the entire pipe, hydraulic testing of type I pipes is allowed not to be carried out. Instead of non-destructive testing of welded seams of type I pipes, it is allowed to test each pipe with increased hydraulic pressure calculated in accordance with the requirements of GOST 3845-75 at an allowable stress equal to 85% of the yield strength for pipes with a diameter of 273 mm and more and 75% of the yield strength for pipes with a diameter of less than 273 mm, but not exceeding 12 MPa (120 kgf / cm 2). Group D pipes must be subjected to a hydraulic pressure test or weld inspection by non-destructive methods. (Introduced additionally, Rev. No. 3). (Revised edition, Rev. No. 5). (Amendment,). 3.4. To check the height of the internal burr, 2% of the pipes from the batch are selected. 3.5. For tests on flattening, expanding, beading, bending, impact strength, the tendency of the base metal of pipes to mechanical aging, stretching of the base metal and the weld, two pipes are taken from the batch. The yield strength of the base metal of pipes is determined at the request of the consumer. At the request of the consumer, the determination of impact strength is not carried out. Pipes subjected to the flattening test are not subjected to the expansion test. (Revised edition, Rev. No. 1). 3.6. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on it on a double number of pipes selected from the same batch. The retest results apply to the entire lot. 3.7. Welding joints of pipes of groups A, B, C must be controlled by non-destructive methods, and repaired pipes are tested by hydraulic pressure in accordance with the requirements of clause 3.3a of this standard. Welding joints of pipes of group D must be tested by non-destructive methods, or pipes after repair must be tested with hydraulic pressure. (Introduced additionally, Rev. No. 1, Amended edition, Rev. No. 5).

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test, and for impact testing, three samples are cut for each test temperature. 4.2. The chemical composition of steel is determined according to GOST 22536.0-87; GOST 22536.1-88; GOST 22536.2-87; GOST 22536.3-88; GOST 22536.4-88; GOST 22536.5-87; GOST 22536.6-88 GOST 12344-88; GOST 12345-88; GOST 12346-78; GOST 12347-77, GOST 12348-78; GOST 12349-83; GOST 12350-78; GOST 12351-81; GOST 12352-81; GOST 12353-78; GOST 12354-81. Samples for determining the chemical composition are taken according to GOST 7565-81. 4.3. Inspection of the surface of the pipes is carried out visually. The depth of defects is checked by sawing or in another way. It is allowed to control the surface and dimensions of pipes by non-destructive methods according to technical documentation. (Revised edition, Rev. No. 1). 4.4. Pipes are measured: length - tape measure but GOST 7502-89. outer diameter and ovality - adjustable measuring bracket according to GOST 2216-84 or caliper according to GOST 166-89 or micrometer according to GOST 6507-89;; or a caliper according to GOST 166-89, or a micrometer according to GOST 6507-89; inner diameter - with a stopper in accordance with GOST 14810-69, or with a caliber in accordance with GOST 2015-84, or by subtracting two wall thicknesses from the outer diameter; curvature - with a straightedge in accordance with GOST 8026-92 and a probe; wall thickness, thickness difference and height of the internal burr - with a micrometer according to GOST 6507-90 or a wall gauge according to GOST 11358-89; edge offset - with a template according to technical documentation or a micrometer in accordance with GOST 6507-90 or a depth gauge in accordance with GOST 162-90; the cut oblique is provided by the design of equipment for processing the ends of pipes, the bevel angle of the chamfer is provided by a goniometer in accordance with GOST 5378-88. In case of disagreement in assessing the quality of the cut, the cut is checked with a coal miner and a probe; end ring at the ends of the pipes - with a ruler according to GOST 427-75; the depth of surface defects - with a depth gauge according to GOST 162-90. Measurement of the outer diameter of the pipe is carried out at a distance of at least 15 mm from the end of the pipe for pipes with a ratio of outer diameter to wall thickness D H / S H equal to 35 or less; at a distance of at least 2/3 D H - for pipes with a ratio of D H / S H over 35 to 75; at a distance of at least D H - for pipes with a ratio of D H / S H over 75. (Changed edition, Rev. No. 1, 3). 4.5. The impact bending test is carried out on longitudinal samples of type 3 according to GOST 9454-78, cut from a pipe section located at an angle of about 90 ° to the weld. Impact strength is determined as the arithmetic mean of the test results of three samples. On one of the samples, a decrease in impact strength by 9.8 10 4 J / m 2 (1 kgf m / cm 2) is allowed. The temperature of the test for impact bending of pipes made of steel grades 08, 10, 15 and 20 is chosen by the consumer. (Revised edition, Rev. No. 1). 4.6. The tendency of the base metal of pipes to mechanical aging is determined according to GOST 7268-82. Editing of samples by static load is allowed. 4.7. The tensile test is carried out according to GOST 10006-80 on a longitudinal (in the form of a strip or pipe section) proportional short sample. When testing on samples of a segmental section, the latter is cut out from a section located at an angle of about 90 ° to the weld, and is not straightened in the calculated part. Instead of tensile testing, it is allowed to control the tensile strength, yield strength and relative elongation of pipes by non-destructive methods. In case of disagreement, pipes are tested in accordance with GOST 10006-80. (Revised edition, Rev. No. 1). 4.8. The flattening test is carried out according to GOST 8695-75 4.9. The expansion test is carried out according to GOST 8694-75 on a mandrel with a taper of 30°. It is allowed to use mandrels with a taper of 1:10 and deburring at the distribution area. (Revised edition, Rev. No. 3). 4.10. The bend test is carried out according to GOST 3728-78. Pipes with a diameter of 114 mm are tested on cut longitudinal strips 12 mm wide. 4.11. The beading test is carried out according to GOST 8693-80. Burr removal is allowed in the flanging area. 4.12. Determination of the temporary resistance of a welded joint of pipes with a diameter of 50-30 mm is carried out on ring samples according to technical documentation. On pipes with a diameter of 219 mm or more, it is allowed to test in accordance with GOST 6996-66 on specimens of type XII with removed reinforcement of the welded joint, cut perpendicular to the axis of the pipe, using a static load when straightening the specimens. 4.13. Hydraulic testing of pipes is carried out in accordance with GOST 3845-75 with exposure under pressure for 5 s. 4.14. The control of the weld is carried out by non-destructive methods (ultrasonic, eddy current, magnetic or x-ray equivalent method) according to the technical documentation.

5. MARKING, PACKAGING, TRANSPORT AND STORAGE

5.1. Marking, packaging, transportation and storage in accordance with GOST 10692-80.

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of Ferrous Metallurgy of the USSR DEVELOPERS: M. M. Bernshtein, N. F. Kuzenko REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Item number		Item number
GOST 162-90		GOST 11358-89
GOST 166-89		GOST 12344-88
GOST 380-88		GOST 12345-88
GOST 427-75		GOST 12346-78
GOST 1050-88		GOST 12347-77
GOST 2015-84		GOST 12348-78
GOST 2216-84		GOST 12349-83
GOST 3728-78		GOST 12350-78
GOST 3845-75		GOST 12351-81
GOST 5378-88		GOST 12352-81
GOST 6507-90		GOST 12353-78
GOST 6996-66		GOST 12354-81
GOST 7268-82		GOST 14637-89
GOST 7502-89		GOST 14810-69
GOST 7565-81		GOST 16523--89
GOST 8026-92		GOST 18242-72
GOST 8693-80		GOST 22536.0-87
GOST 8694-75		GOST 22536.1-88
GOST 8695-75		GOST 22536.2-87
GOST 9045-80		GOST 22536.3-88
GOST 9454-78		GOST 22536.4-88
GOST 10006-80		GOST 22536.5-87
GOST 10692-80		GOST 22536.6-88
GOST 10704-91

5. REPUBLICATION (June 1993) with Amendments No. 1, 2, 3, 4, 5 approved in December 1986, December 1987, June 1989, July 1991; May 1999 (IUS 2-7, 3-8, 10-9, 10-1; 7-1999). Amendment (IUS 5-2005)

1. ASSORTMENT. 1 2. TECHNICAL REQUIREMENTS.. 1 3. ACCEPTANCE RULES.. 5 4. TEST METHODS.. 6 5. MARKING, PACKAGING, TRANSPORTATION AND STORAGE. 7 INFORMATION DATA. 7

Manufactured pipe products must meet certain requirements. Therefore, there is GOST 10705-80 for electric-welded steel pipes, the technical conditions of which regulate the characteristics of the corresponding standard products.

1 GOST 10705-80 - standard for electric-welded pipes

Specifications (abbreviated TS) - a document that regulates the technical requirements for specific substances, materials, products, other things, or a group of them. These products, when manufactured, must meet the requirements, which, in addition, indicate the procedures to determine how they are met.

Specifications GOST 10705-80 is a standard that applies to longitudinally welded steel pipes with a diameter (hereinafter D) of 10–530 mm from low-alloy and carbon steel grades, widely used in the construction of structures and pipelines for various industrial and technical purposes. This standard does not apply to products intended for the manufacture of thermal electric heaters.

According to GOST 10705-80, straight-seam electric-welded steel pipes, the assortment of which is regulated by GOST 10704-91 in terms of dimensions and permitted maximum deviations, must comply with the following technical requirements. Depending on the required quality indicators of pipe products, they are manufactured in the following groups:

A - with the mechanical properties of established standards from calm, boiling, semi-quiet steel grades St1, St2, St3, St4 according to GOST 380-94;
B - with the chemical composition of the established norms of steel:
- calm, boiling, semi-calm brands:
  - St1–St4 according to GOST 14637-89 and GOST 380-94;
- 08Yu according to GOST 9045-93;
- low-alloyed 22GU (pipes with a diameter of 140-426 mm) with a chemical composition specified in Appendix 1;
B - with the chemical composition, as well as the mechanical properties of the established norms of steel:
- semi-calm, boiling, calm brands:
  - St1–St4 according to GOST 380-94;
  - 20, 15, 10, 08 according to GOST 1050-88;
- 08Yu according to GOST 9045-93;
- low-alloyed 22GU (pipes with a diameter of 140-426 mm) with a chemical composition specified in Appendix 1;
D - with hydraulic test pressure of established standards.

According to the type of heat treatment, pipes are made:

heat treated (according to welding joint or the whole volume);
hot-reduced;
without processing.

Heat treatment of tubular products throughout the volume is chosen by the manufacturer. The intended temperature effect can be carried out in a protective atmosphere (by agreement between the consumer and the manufacturer). Products from steel 22GU are produced processed according to welding seam or the entire volume, and from St1 - without processing.

2 Requirements for mechanical performance and properties

According to GOST 10705-80, specifications regulate the following mechanical parameters of the base metal of products:

hot-reduced and heat-treated carbon steels, corresponding to the values shown in Table 1;
heat-treated steel 022GU - by agreement of the parties;
without heat treatment and with weld seam treatment:
- D from 10 to and equal to 152 mm, corresponding to the values reflected in Table 2;
- D more than 152 up to and equal to 530 mm, corresponding to the values reflected in Table 3.

The surface of pipe products should not have captivity, cracks, risks, flaws and sunsets. Nicks, ripples, small risks, dents, traces of cleaning and a layer of scale are acceptable, provided that the diameter of the product and the thickness of its wall are not deduced by defects beyond the maximum deviations. The maximum permitted edge offset from the nominal thickness is 10%.

The surface of pipes thermally treated in a protective atmosphere may have an oxide film, but must be free of scale.

The manufacturer welds the lack of penetration of the seams, and cleans the place of repair. Upon agreement with the consumer, on products with a diameter of 159 mm or more, in the places where the seams are finished, the offset of the edges to be welded should not exceed 20% of the wall thickness provided for by the norms, and the reinforcement bead is made with a maximum height of 2.5 mm. Repair of the base metal of products is not allowed. Pipes, after repair by welding, are subjected to repeated heat treatment (respectively for the welding joint or the entire volume).

1 transverse seam is allowed on products D (in mm):

57 and more;
less than 57 - by mutual agreement between the manufacturer and the customer.

The external burr present on the pipes must be removed. In the place of its removal, thinning of the wall in excess of the tolerance (minus) of 0.1 mm is allowed. At the request of the customer, for tubular products with an internal D of 33 mm or more, the internal burr is partially removed or flattened, while its height or the height of traces from it should be (in mm):

0.35 or less - for walls less than 2 mm thick;
0.4 - 2-3 mm;
0.5 - over 3 mm.

For products with an internal diameter of up to 33 mm, the height of the burr, its traces is set by agreement between the customer and the manufacturer. Tubular products must have ends cut strictly at right angles and deburred. Chamfering is allowed. For products D up to 219 mm, the cut angle should be a maximum of 1 mm, and for D 219 mm and more - 1.5 mm.

According to the application of the consumer, at the ends of products with a wall thickness of 5 mm or more, chamfer is chamfered at a bevel angle of 25–30 ° to the end surface of the pipe, leaving an end ring 1.8 mm ± 0.8 mm wide (by agreement between the customer and the manufacturer, the width of the ring , bevel angle may be different).

3 Requirements for hydraulic and mechanical testing of pipes

Products must withstand hydraulic test pressure, according to the magnitude of which the pipes are divided into types:

I - D up to 102 mm (pressure value 6.0 MPa), D 102 mm and more (pressure value 3.0 MPa);
II - products of groups A, B, which are manufactured according to the requirements of the customer with a hydraulic test pressure regulated by GOST 3845-75, with a permitted stress of 90% of the standard yield threshold for pipe products from this steel, but not exceeding 20 MPa.

For heat-treated products made of steel St3ps, St3sp, 10, 15 and 20 with walls 6 mm thick or more, the base metal is tested for impact bending (the required impact strength is given in Table 4). Heat-treated products made of steel 22GU are tested for impact bending in the event of a customer's request, the viscosity standards are set by mutual agreement of the parties.

Heat-treated pipes D up to and equal to 152 mm, products without heat treatment and hot-reduced, D of which is more than 20 up to and equal to 152 mm and with walls with a thickness of 0.06 Dn or less, as well as pipe products with heat treatment of the weld must withstand test loads for flattening .

For products D up to 108 mm, distribution tests are carried out. Pipe products without heat treatment D up to 20 mm, and D 20–60 mm with walls with a thickness of more than 0.06 DH are not subjected to expansion tests. The outer diameter of heat-treated pipes should increase during expansion in accordance with the established norms, reflected in Table 5.

For products without heat treatment, the increase in diameter during expanding should be at least 6%. In the case of customer requirements, the outer diameter of heat-treated products made of steel 10kp, St2kp with walls up to 4 mm thick should increase during expansion by at least 12%. At the request of the consumer, the products are tested for bending, beading, stretching. After all the checks carried out, the steel electric-welded longitudinal pipes GOST 10705-80 must remain airtight.

Appendix 1. Chemical composition of steel grade 22GU.

Mass fraction of elements in% (no more):

carbon - 0.15–0.22;
silicon - 0.15–0.30;
manganese - 1.20–1.40;
aluminum - 0.02–0.05;
titanium - 0.03;
chromium - 0.4;
nitrogen - 0.012;
calcium - 0.02;
sulfur - 0.01;
phosphorus - 0.02.

Table 1

Note. At the request of the consumer, pipes with a wall thickness of 4 mm or more of steel grades St3sp, 15, 15ps are made with a yield strength of 235 N / mm 2 (24 kgf / mm 2), relative elongation of 23%; from steel grades St4sp, 20, 20ps - with a yield strength of 255 N / mm 2 (26 kgf / mm 2), relative elongation of 22%.

table 2

steel grade	Temporary resistance gap s in, N / mm 2 (kgf / mm 2), with the outer diameter of the pipes D, mm	fluidity s t, N/mm 2 (kgf/mm 2)	with outer diameter of pipes
			from 10 to 60 for wall thickness
			over 0.06 D	0,06 D and less

08Yu
08ps, 08kp, St1ps, St1kp
08, St1sp
10kp, St2kp
10ps, St2ps
10, St2sp
15kp
15ps, 20kp
15, 20ps
20
St3kp
St3ps
St3sp
St4kp, St4ps
St4sp
22GU

Note. At the request of the consumer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation is increased by 3% compared to the standards given in Table 2.

Table 3

steel grade		Temporary resistance break s in,	Yield strength s t, N / mm 2 (kgf / mm 2)	Relative elongation d s , %, with outer diameter of pipes D, mm
		Temporary resistance break s in,	Yield strength s t, N / mm 2 (kgf / mm 2)	St. 152 to 244.5	St. 244.5 to 377	St. 377 to 530

08.08ps, 08kp	6 or less
10, 10ps, 10kp, St2kp	More than 6
St2sp, St2ps	6 or less
	More than 6
15, 15ps, 15kp	6 or less
20, 20ps, 20kpp	More than 6
St3sp, St3ps	6 or less
St3kp	More than 6
St4sp, St4ps	6 or less
St4kp	More than 6
22GU	All thicknesses

Table 4

GOST 10705-80

INTERSTATE STANDARD

ELECTRIC WELDED STEEL PIPES

TECHNICAL CONDITIONS

Introduction date 01.01.82

This standard applies to steel electric-welded longitudinal pipes with a diameter of 10 to 630 mm from carbon and low-alloy steel grades used for pipelines, structures, and products for various purposes.

The standard does not apply to steel pipes used for the manufacture of thermal electric heaters.

1. ASSORTMENT

1.1. Dimensions and maximum deviations of pipes must comply with GOST 10704.

2. TECHNICAL REQUIREMENTS

2.1. Steel electric-welded pipes are manufactured in accordance with the requirements of this standard and according to technical regulations approved in the prescribed manner.

2.2. Depending on the quality indicators, pipes are manufactured in the following groups:

A - with standardization of mechanical properties from calm, semi-quiet and boiling steel grades St1, St2, St3, St4 according to GOST 380;

B - with normalization of the chemical composition:

GOST 19281

B - with standardization of mechanical properties and chemical composition:

From calm, semi-calm and boiling steel grades St1, St2, St3, St4 according to GOST 380;

From calm, semi-calm and boiling steel grades 08, 10, 15, 20 according to GOST 1050;

From steel grade 08Yu according to GOST 9045;

From low-alloy steel grade 22GU with a chemical composition according to table 1a (pipes with a diameter of 114 to 630 mm inclusive);

From low-alloy steel grades in accordance with GOST 19281 and other regulatory documents with a normalized carbon equivalent of not more than 0.46% (pipes with a diameter of 114 to 630 mm inclusive);

D - with standardization of test hydraulic pressure.

Pipes are made from rolled products according to GOST 14637 (categories 1 - 5), GOST 16523 (category 4), GOST 9045, GOST 19281 and others regulatory documents approved in the prescribed manner.

Table 1a

Steel grade	Mass fraction of elements, %
		Manganese	Aluminum
				no more

Note. Permissible deviations in the mass fraction of elements from the norms given in the table must comply with GOST 19281

2.3. Pipes from carbon steel grades are produced heat-treated (throughout the entire volume of the pipe or along the welded joint), hot-reduced or without heat treatment. Pipes from steel grade St1 are produced without heat treatment.

Pipes from low-alloy steel grades are produced heat-treated (throughout the entire volume of the pipe or along the welded joint) or without heat treatment.

The type of heat treatment is chosen by the manufacturer. By agreement between the manufacturer and the customer, the pipes are thermally treated in a protective atmosphere.

2.2, 2.3 (New edition, Rev. No. 6).

2.4. The mechanical properties of the base metal of heat-treated and hot-reduced pipes of groups A and B from carbon and low-alloy steels must comply with the standards specified in Art. The mechanical properties of the base metal of heat-treated pipes of groups A and B from steel grade 22GU are established by agreement between the manufacturer and the consumer.

steel grade	Relative elongation d 5 %	steel grade	Tensile strength s in, N / mm 2 (kgf / mm 2)	Yield strength s t N / mm 2 (kgf / mm 2)	Relative elongation d 5 %
steel grade		steel grade
		St4sp, St4ps,

08, 08ps, 10kp
10, 10ps, 15kp, St2sp, St2kp,		20F, 20-CSH, 06GB
20kp, St3ps, St3sp, St3kp		09G2S, 09GSF, 13HFA, 17GS, 17G1S, 17G1S-U, 08HMFCHA, 22GF, 26HMA

Note. At the request of the customer, pipes with a wall thickness of 4 mm or more from steel grades St3sp, 15, 15ps are manufactured with a yield strength of 235 N / mm 2 (24 kgf / mm 2), relative elongation of 23%; from steel grades St4sp, 20, 20ps - with a yield strength of 255 N / mm 2 (26 kgf / mm 2), relative elongation of 22%.

(Changed edition, Rev. No. 6,).

steel grade

Tensile strength s in, N / mm 2 (kgf / mm 2), with the outer diameter of the pipes D, mm

Relative elongation d s , %, with the outer diameter of the pipes D, mm

St. 19 to 60

St. 60 to 152

from 10 to 60 for wall thickness

St. 60 to 152

over 0.06 D

0,06 D and less

St1ps, St1kp

10kp, St2kp

10ps, St2ps

St4kp, St4ps

20F, 20-CSH, 06GB

09G2S, 09GSF, 13HFA, 17GS, 17G1S, 17G1S-U, 08HMFCHA, 22GF, 26HMA

Note. At the request of the customer, for pipes of all grades of steel with a diameter of 10 to 60 mm, the relative elongation is increased by 3% compared to the standards given in.

steel grade	Wall thickness, mm	Tensile strength s in, N / mm 2 (kgf / mm 2),	Yield strength s t, N / mm 2 (kgf / mm 2)	Relative elongation d s , %, with the outer diameter of the pipes D, mm
		Tensile strength s in, N / mm 2 (kgf / mm 2),	Yield strength s t, N / mm 2 (kgf / mm 2)	St. 152 to 244.5	St. 244.5 to 377	St. 377 to 630

08.08ps, 08kp
10, 10ps, 10kp, St2kp
St2sp, St2ps
St2sp, St2ps
15, 15ps, 15kp, 20, 20ps, 20kp
15, 15ps, 15kp, 20, 20ps, 20kp
St3sp, St3ps, St3kp
St3sp, St3ps, St3kp
St4sp, St4ps, St4kp
St4sp, St4ps, St4kp
	All thicknesses
20F, 20-CSH, 06GB	All thicknesses
09G2S, 09GSF, 13HFA, 13GS, 17GS, 17G1S, 17G1S-U, 08HMFCHA, 22GF, 26HMA	All thicknesses
	All thicknesses

(Revision, Rev. No. 7)

2.5. The mechanical properties of the base metal of pipes of groups A and B without heat treatment and with heat treatment of a welded joint with a diameter of 10 to 152 mm inclusive must comply with the standards specified in c, with a diameter of more than 152 to 630 mm inclusive - the standards specified in c.

2.6. Cracks, captivity, sunsets, flaws and risks are not allowed on the pipe surface.

The surface of pipes heat-treated in a protective atmosphere must be free of scale. The presence of an oxide film is allowed.

Lack of penetration of seams must be welded, the place of welding is cleaned. By agreement with the customer, on pipes with a diameter of 159 mm or more, in places where welds are repaired by welding, the offset of the welded edges is allowed no more than 20% of the nominal wall thickness and the height of the reinforcement bead is not more than 2.5 mm.

Repair by welding of the main metal of pipes is not allowed.

In the case of repair by welding of pipes that have undergone heat treatment, they are subjected to repeated heat treatment (respectively, over the entire volume or over the welded joint).

2.7. On pipes with a diameter of 57 mm or more, one transverse seam is allowed.

By agreement between the manufacturer and the customer, one transverse seam is allowed on pipes with a diameter of less than 57 mm.

2.8. The outer burr on the pipes must be removed. At the place of deburring, the wall may be thinned by 0.1 mm in excess of the minus tolerance.

At the request of the customer, on pipes with an internal diameter of 33 mm or more, the internal burr must be partially removed or flattened, while the height of the burr or its traces should not exceed 0.35 mm - with a wall thickness of less than 2 mm; 0.4 mm - with a wall thickness of 2 to 3 mm; 0.5 mm - with a wall thickness of more than 3 mm.

The height of the internal burr or its traces for pipes with an internal diameter of less than 33 mm is set by agreement between the manufacturer and the customer.

2.9. Pipe ends must be square cut and deburred. The formation of a chamfer is allowed. The oblique cut for pipes with a diameter of up to 219 mm should not exceed 1.0 mm, with a diameter from 219 to 426 mm inclusive - 1.5 mm, with a diameter of more than 426 mm - 2.0 mm. By agreement between the manufacturer and the customer, the pipes are made cut in the line of the mill.

2.10. At the request of the customer, at the ends of pipes with a wall thickness of 5 mm or more, a chamfer should be chamfered at an angle of 25 - 30 ° to the end of the pipe and an end ring with a width of (1.8 ± 0.8) mm should be left. By agreement between the manufacturer and the customer, the bevel angle and the width of the end ring can be changed.

2.11. Pipes must withstand the test hydraulic pressure. Depending on the magnitude of the test pressure, pipes are divided into two types:

I - pipes with a diameter of up to 102 mm - test pressure 6.0 MPa (60 kgf / cm 2) and pipes with a diameter of 102 mm or more - test pressure 3.0 MPa (30 kgf / cm 2);

II - pipes of groups A and B, supplied at the request of the customer with a test hydraulic pressure calculated in accordance with GOST 3845, at an allowable stress equal to 90% of the standard yield strength for pipes made of this steel grade, but not exceeding 20 MPa (200 kgf / cm 2).

(Revised edition, Rev. No. 5).

2.12. Pipes heat-treated throughout the volume, groups A and B, with a wall thickness of at least 6 mm, made of steel grades St3sp, St3ps (categories 3-5), 10, 15, 20 and low-alloy steels, must withstand the impact bending tests of the base metal . In this case, the norms of impact strength must correspond to those indicated in Table. . The impact bending test of the base metal of heat-treated pipes of groups A and B made of steel grade 22GU is carried out at the request of the customer, the impact strength standards are set by agreement between the manufacturer and the customer.

2.13. Heat-treated pipes with a diameter of up to 152 mm inclusive, hot-reduced and non-heat-treated pipes with a diameter of more than 20 to 152 mm inclusive and a wall thickness of 0.06 D n and less, as well as pipes with heat treatment of the welded joint must withstand the flattening test.

Flattening of heat-treated pipes should be carried out up to the distance between the flattening planes H, mm, calculated by the formula

where a- the coefficient for pipes made of steel grades 08Yu, 08kp, 8ps.08, 10kp, St2kp is 0.09, and for pipes made of other steel grades it is 0.08;

S– nominal wall thickness, mm;

D n - nominal outer diameter of the pipe, mm.

Flattening of pipes without heat treatment should be carried out up to a distance equal to 2/3 D H . Flattening pipes with heat treatment of the welded joint and hot reduced pipes should be carried out to a distance equal to 1/2D H.

At the request of the customer, flattening of heat-treated pipes with a diameter of more than 152 to 530 mm should be carried out to a distance equal to 2/3 D n.

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

2.14. Pipes up to 108 mm in diameter must pass the expansion test.

Pipes with a diameter of up to 108 mm made of carbon steel grades specified in table 5 must pass the expansion test.

The increase in the outer diameter of heat-treated pipes during expansion must comply with the standards specified in Art.

The increase in the outer diameter of pipes without heat treatment during expansion should be at least 6%.

At the request of the customer, the increase in the outer diameter during the distribution of heat-treated pipes with a wall thickness of up to 4 mm from steel grades 10kp, St2kp must be at least 12%.

(Changed edition, Rev. No. 1, 4,).

2.15. At the request of the customer, the pipes must withstand the tests provided for in paragraphs. - .

2.17. Heat-treated throughout the volume of carbon steel pipes with a diameter of 30 to 159 mm with a wall thickness of not more than 0.08 Dmust pass the flight test. The flanging value must be at least 24%, while the width of the bent flange, measured from the inner surface of the pipe, must be at least 1.5 of the pipe wall thickness.

The angle of the flanging should be:

90 ° - for pipes made of steel grades 08, 10, 15, St2;

60 ° - for pipes made of steel grades 20, St3, St4.

The temporary resistance of the welded joint of pipes without heat treatment with a diameter of 50 mm or more must comply with the standards specified in and.

(Changed edition, Rev. No. 1,).

2.19. Pipes must be sealed.

3. ACCEPTANCE RULES

The number of pipes in a batch should not exceed, pcs.:

1000 - with a diameter of up to 30 mm;

600 - with a diameter of St. 30 to 76 mm;

400 - with a diameter of St. 76 to 152 mm;

200 - with a diameter of St. 152 mm.

(Revised edition, Rev. No. 1).

3.2. In case of disagreement in assessing the quality of the chemical composition, at least one pipe from the batch is selected for verification.

3.3. Each pipe is subjected to control of the dimensions and quality of the pipe surface. It is allowed to control the dimensions and surface selectively on each batch with a single-stage normal level of control in accordance with the requirements of GOST 18242 *. Control plans are established by agreement between the manufacturer and the customer.

(Revised edition, Rev. No. 3).

* On the territory of the Russian Federation, GOST R 50779.71-99 applies **.

* See FSUE STANDARTINFORM.

3.4. To check the height of the internal burr, 2% of the pipes from the batch are selected.

The yield strength of the base metal of pipes is determined at the request of the customer.

Pipes subjected to the flattening test are not subjected to the expansion test.

(Changed edition, Rev. No. 1,).