GOST 14959-79 Rolled products from spring carbon and alloy steel. Specifications

GOST 14959-79

INTERSTATE STANDARD

ROLLED CARBON AND ALLOY STEEL SPRINGS

TECHNICAL CONDITIONS

IPC PUBLISHING HOUSE OF STANDARDS Moscow

INTERSTATE STANDARD

Date of introduction 01/01/81

This standard applies to hot-rolled and forged sections with a diameter or thickness of up to 250 mm, as well as calibrated rolled products with special surface finishing, intended for the manufacture of springs, leaf springs and other parts of machines and mechanisms used in a quenched and tempered state.

In terms of chemical composition standards, the standard applies to all other types of rolled products, ingots, forgings and stampings.

(Changed edition, Amendment No. 5).

CLASSIFICATION AND ASSORTMENT

1.1. Rentals are divided into:

by processing method:

hot rolled and forged;

calibrated;

with special surface finishing;

hot-rolled round with a turned or ground surface;

according to the chemical composition of steel:

quality;

high quality - A;

according to standardized characteristics and application into categories: 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 3B, 3G, 4, 4A, 4B.

(Changed edition, Amendment No. 5).

(Amendment, IUS 1-2000).

1.2. Depending on the quality of the surface, hot-rolled and forged products of categories 1, 1A, 1B, 4, 4A, 4B are produced in groups 2GP and 3GP.

1.3. The range of rolled products and maximum deviations in size must meet the requirements:

GOST 2590 - for hot-rolled rounds, including turned ones;

GOST 2591 - for hot-rolled square;

GOST 1133 - for forged round and square;

GOST 2879 - for hot-rolled hexagonal;

GOST 103 - for hot-rolled strip;

GOST 4405 - for forged strip;

GOST 7419 - for hot-rolled strip, trapezoidal-step, T-shaped, trapezoidal and grooved categories 2, 2A, 2B, 3, 3A, 3B, 3B and 3G;

GOST 7417 - for calibrated round;

GOST 8559 - for calibrated square;

GOST 8560 - for calibrated hexagonal;

GOST 14955 - with special surface finishing;

other regulatory and technical documentation.

Examples of symbols

Hot-rolled, round, 100 mm in diameter, normal rolling accuracy B according to GOST 2590-88, made of steel grade 65G, surface quality group 2GP, category 4A:

Circle V-100 GOST 2590-88/65G-2GP-4A GOST 14959-79

Hot rolled products, square, with a square side of 30 mm, normal rolling accuracy B according to GOST 2591-88, from steel grade 50HFA, category 3A:

Square V-30 GOST 2591-88/50HFA-3A GOST 14959-79

Hot-rolled, trapezoidal, dimensions (H ´ H) 45 ´ 6, increased rolling accuracy B according to GOST 7419-90, made of steel grade 60S2A, category 3B:

Trapezoidal strip B-45 ´ 6 GOST 7419-90/60S2A-3B GOST 14959-79

Calibrated rolled products, round, with maximum deviations according to h11 in accordance with GOST 7417-75, with a diameter of 15 mm, made of steel grade 50HFA, category 3A, surface quality group B in accordance with GOST 1051-73:

Circle h11-15 GOST 7417-75/50HFA-B-3A GOST 14959-79

Rolled products with special surface finishing, round, 20 mm in diameter, with maximum deviations according to h10, surface finishing group D according to GOST 14955-77, from steel grade 80, category 3A:

Circle h10-20 GOST 14955-77/80-D-3A GOST 14959-79

Hot-rolled, round, 6 mm in diameter, normal rolling accuracy B according to GOST 2590-88, made of steel grade 65G, surface quality group 3GP, category 1A, for pantent wire:

Circle V-6 GOST 2590-88/65G-3GP-1A GOST 14959-79, for patented wire.

Examples of symbols that can be given in design documentation:

Hot-rolled, round, 100 mm in diameter, normal rolling accuracy B according to GOST 2590-88, made of steel grade 65G, surface quality group 2GP, category 4A:

Circle

.

(Amendment, IUS 1-2000).

1.2-1.3. (Changed edition, Amendment No. 6).

TECHNICAL REQUIREMENTS

2.1. Rolled products from spring-carbon and alloy steel must be manufactured in accordance with the requirements of this standard according to technological regulations approved in the prescribed manner.

(Amendment, IUS 1-2000).

2.2. The grades and chemical composition of steel according to heat analysis must comply with the standards specified in table. 1.

Table 1

Notes:

1. In the designation of steel grades, the first two digits indicate the average mass fraction of carbon in hundredths of a percent, the letters behind the numbers mean: G - manganese, C - silicon, X - chromium, F - vanadium, B - tungsten, N - nickel. The numbers following the letters indicate the approximate mass fraction of the element in whole units. The absence of a number means that the brand contains up to 1.5% of this alloying element. When the mass fraction of an element is over 1.5% to 2.5%, the number 2 is placed after the letter corresponding to the element, over 2.5% - the number 3. In the name of steel grades, with a mass fraction of up to 0.9% manganese (at the top limit), the letter “G” is not placed.

2. In steel of all grades, the mass fraction of residual copper should not exceed 0.20%, and residual nickel - 0.25%.

3. In accordance with the order, in steel produced by the scrap process and the scrap ore process, the residual mass fraction of copper is not more than 0.30% and nickel is not more than 0.40% for rolled products of all categories, chromium is not more than 0.30% for rolled products of categories 2, 2A, 2B, 3, 3A, 3B, 3B and 3G from carbon steel and no more than 0.40% for rolled products of categories 1, 1A, 1B, 4, 4A and 4B.

4. In steel grade 60S2G, the total mass fraction of sulfur and phosphorus should not exceed 0.06%.

5. Steel grade 51HFA is intended for the production of spring wire.

6. For the manufacture of patented wire, steel grades 65, 70, 75, 80, 85 are used with a mass fraction of manganese of 0.30 - 0.60% and grades 65G and 70G with a mass fraction of manganese of 0.70 - 1.00%. In steel intended for patented wire, the mass fraction of chromium should not exceed 0.15%, nickel - 0.15%, copper - 0.20%. The mass fraction of sulfur and phosphorus is in accordance with the requirements of the wire standards, but not more than the standards specified in the table. 2. In accordance with the order, in steel grades 65, 70, 75, 80 and 85, intended for the production of patented wire, the mass fraction of manganese is 0.40 - 0.70%.

7. At the request of the consumer, the lower mass fraction of manganese in steel not alloyed with chromium and nickel can be reduced against the standards of Table. 1 per manganese equivalent ( E

m), but not more than 0.30%.

The value of manganese equivalent is determined by the formula

E

m = 0.3 (Cr, %) + 0.5 (Ni, %) + 0.7 (Cu, %),

where Cr, Ni, Cu is the residual mass fraction of chromium, nickel, copper in steel, not exceeding the standards of the table. 1.

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

(Amendment, IUS 1-2000).

2.3. The mass fraction of phosphorus and sulfur according to melting analysis in steel of all grades should not exceed the standards specified in table. 2.

table 2

Notes:

1. Rolled products from high-quality steel grades 65, 70, 75, 80, 85, 60G, 65G and 70G can be manufactured with a mass fraction of sulfur and phosphorus in accordance with the requirements of Table. 2 for high quality steel. In this case, the letter A is added to the name of the steel grade.

2. In rolled products made of high-quality steel grades 65, 70, 75, 80, 85, 60G, 65G, 70G, categories 1, 1A, 1B, 4, 4A, 4B, the mass fraction of sulfur is allowed up to 0.040%.

(Changed edition, Amendment No. 5).

(Amendment, IUS 1-2000).

2.4. Permissible deviations in the chemical composition of the finished rolled products should not exceed the values ​​​​specified in table. 3.

Table 3

* Deviations for steel grades 55S2A, 60S2A, 50HGA are not allowed.

**

For high-quality steel, phosphorus deviation is not allowed.

2.5. Depending on the standardized characteristics, rolled products are manufactured according to the categories indicated in Table. 4.

Appendix 1 shows the purpose of rental depending on categories.

(Amendment, IUS 1-2000).

2.5.1. Rolled products are produced in a heat-treated state (annealed or highly tempered) - categories 1A, 2A, 3A, 3B, 4A, or without heat treatment - categories 1, 1B, 2, 2B, 3, 3B, 3G, 4, 4B.

Table 4

Notes:

1. The “+” sign means that the characteristic is normalized. The sign “-” means that the characteristic is not standardized.

2. For rolled products with special surface finishing, decarburization is checked for all categories of rolled products.

(Changed edition, Amendment No. 2).

2.6. The hardness of rolled products must comply with the standards specified in table. 5.

Table 5

Note. When producing rolled products without heat treatment in coils, deviations in hardness of + 10HB are allowed.

(Changed edition, Amendment No. 2).

(Amendment, IUS 1-2000).

2.7. Mechanical properties of rolled products of categories 3, 3A, 3B ,

3B, 3G, 4, 4A, 4B, determined on heat-treated longitudinal samples, must comply with the standards specified in table. 6.

Table 6

Notes:

1. Relative contraction standards are given only for round samples.

2. Heat treatment is carried out on samples intended for mechanical testing.

3. Standards for mechanical properties apply to samples taken from rolled products with a diameter or thickness of up to 80 mm. When testing rolled products with a diameter or thickness over 80 to 150 mm, a reduction in relative elongation by 2% and relative contraction by 5% is allowed compared to the standards specified in Table. 6. For rolled products with a diameter or thickness over 150 mm, a reduction in relative elongation by 3% and relative contraction by 10% is allowed. The standards of mechanical properties of rolled products with a diameter or thickness of over 100 mm, rolled or reforged into a square measuring 90 - 100 mm, must comply with the standards specified in Table. 6.

(Changed edition, Amendment No. 2).

(Amendment, IUS 1-2000).

2.8. The surface quality of the rolled product must meet the requirements of Table. 7.

Table 7

(Changed edition, Amendment No. 5, 6).

2.9. Hot rolled and forged bars and strips must be cut.

The cutting pattern of strips for springs must comply with GOST 7419. The cutting pattern of forged strips, hot-rolled strips (except for spring strips) and rods up to 30 mm in size is not regulated. Over 30 mm - should not exceed 0.1 diameter or thickness. Rods and strips up to 40 mm in size of unmeasured length may be manufactured with uncut ends.

For bars and strips of categories 2, 2A, 2B, 3, 3A, 3B, 3B, 3G, the burrs must be cleaned, bending the ends is not allowed.

When cutting on presses, shears and under hammers, as agreed with the consumer, slight crushing of the ends of rods and strips is allowed. The amount of crushing of the ends, if necessary, is established by agreement between the manufacturer and the consumer.

On rods and strips of categories 1, 1A, 1B, 4, 4A, 4B, crumpled ends and burrs are allowed.

Trimming the ends of calibrated rolled products - in accordance with GOST 1051, with special surface finishing - in accordance with GOST 14955.

(Changed edition, Amendment No. 6).

2.10. The macrostructure of rolled products on fractures or on etched transverse templates should not have residues of shrinkage cavities, looseness, bubbles, delaminations, cracks, slag inclusions and flakes.

Point heterogeneity, central porosity, segregation square should not exceed point 2 according to GOST 10243 for rolled products of categories 2, 2A, 2B, 3, 3A, 3B, 3B, 3G and point 3 for rolled products of other categories.

(Amendment, IUS 1-2000).

2.11. Hot-rolled round rods with a turned and ground surface and special surface finishing are manufactured without a decarbonized layer.

The depth of the decarbonized layer of rolled products of categories 2, 2A, 2B, 3, 3A, 3B, 3B, 3D on the side should not exceed the standards specified in table. 8.

Table 8

2.12. Steel grades 50KhG, 50KhGA, 50KhGFA, 60S2, 55S2, 60S2A, 55S2A must be checked for the size of the austenitic grain. For steel grade 50KhGFA, the size of the austenitic grain should be no larger than number 6, and for steel of other grades - no larger than number 5 according to GOST 5639.

(Changed edition, Amendment No. 2).

2.13. At the consumer's request, steel is produced:

a) with narrowed limits of the mass fraction of carbon compared to the standards of table. 1;

b) with a mass fraction of sulfur not exceeding 0.015% and phosphorus not exceeding 0.020% in high-quality steel;

c) with a standardized austenite grain size no larger than number 5 for steel grades not listed in clause 2.12;

d) with a standardized microstructure;

e) with normalized contamination with non-metallic inclusions;

f) with fatigue testing;

g) with determination of the elastic limit;

h) with control of martensitic and troost-martensitic areas and the depth of sorbitol tempering in the microstructure of rolled products with surface quality of group 2GP, intended for the manufacture of wire.

Note. Standards for subparagraphs a

,
d
,
d
,
f
,
g
,
h
are established by agreement between the consumer and the manufacturer.

(Changed edition, Amendment No. 2, 5).

(Amendment, IUS 1-2000).

2.14. Hardenability standards for rolled products of categories 2, 2A, 2B, 3B, 3G are established by agreement with the consumer.

Appendix 2 shows the hardenability bands for steel grades 55С2, 55С2А, 60С2, 60С2А, 50ХГФА.

Appendix 3 shows the limits of hardness fluctuations (maximum and minimum) along the length of the end samples, Appendix 4 shows the maximum permissible dimensions of rolled products of various grades for the manufacture of springs and springs.

(Amendment, IUS 1-2000).

GOST 2590-2006: Hot-rolled round steel

Hot-rolled round steel. Assortment

Assortment

For hot-rolled round steel with a diameter from 5 to 200 mm inclusive. Rolled products with a diameter of more than 270 mm are manufactured in agreement with the consumer. Rolled products are manufactured with precision:

• A - high accuracy;
• B - increased accuracy;
• B - normal accuracy.
  The diameter of the rolled product, maximum deviations along it, cross-sectional area and weight of 1 m of length must correspond to Table 1.

Table 1

Note: The cross-sectional area and weight of 1 m of profile length are calculated based on the nominal dimensions. When calculating 1 m of rolled steel, the steel density was taken to be 7.85 kg/m3. The weight of 1 m of rolled stock is a reference value. At the request of the consumer, round slopes are manufactured with positive deviations indicated in Table 2.

table 2

The ovality of rolled products should not exceed 50% of the sum of the maximum deviations in diameter. Allowed for alloyed tool and fast cutting rolled products is an ovality not exceeding 60% of the sum of the maximum deviations in diameter.

Rolled products with a diameter of up to 9 mm are produced in coils, over 9 mm - in rods.

In accordance with the order, rolled products are manufactured: to specific length; multiple measured length; unmeasured multiple length.

Rolled products are made in lengths: from 2 to 6 m - from ordinary quality carbon and low-alloy steel; from 2 to 6 m - from high-quality carbon and alloy steel; from 1.0 to 6 m - made of high-alloy steel.

Maximum deviations in the length of rolled products of measured and multiple measured lengths should not exceed: +30 mm - for lengths up to 4 m inclusive; +50 mm - for lengths over 4 m up to 6 m inclusive. +70 mm - for lengths over 6 m.

The curvature of the rods should not exceed the values ​​indicated in Table 3.

Table 3

The curvature of rolled products is measured over a length of at least 1 m at a distance of at least 1 m at a distance of at least 150 mm from the ends.

Diameter. The ovality of round bars is measured at a distance of at least 150 mm from the end of the bar and at least 1.5 m from the end of the coil when its weight is up to 250 kg and at a distance of at least 3.0 m when the coil weighs over 250 kg.

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ACCEPTANCE RULES

3.1. Rolled products are accepted in batches consisting of rolled products of one heat, one size and one heat treatment mode and issued with one quality document in accordance with GOST 7566.

(Changed edition, Amendment No. 2).

3.2. Acceptance rules - according to GOST 7566.

3.3. To check the quality of rolled products, the following are selected from a batch of rods, strips and coils:

for chemical analysis - samples according to GOST 7565; control of residual chromium, copper, nickel is carried out periodically at least once a quarter. When producing steel, taking into account the manganese equivalent, control of residual copper, nickel and chromium is carried out at each heat;

to control the macrostructure by fracture or etching, to determine the microstructure, for tensile tests (yield strength, tensile strength, relative elongation, relative contraction) - two rods or coils, two strips;

to test hardness - no more than 2% of strips (rods, coils), but not less than three strips (rods, coils);

to determine hardenability - one sample from the melt - ladle;

to determine the depth of the decarbonized layer - three rods, strips or coils;

to determine the grain size - one sample from the melt - ladle;

to determine non-metallic inclusions - samples according to GOST 1778;

to control surface quality and dimensions - all rods, strips and coils.

(Changed edition, Amendment No. 2).

(Amendment, IUS 1-2000).

Mechanical properties of steel 60С2А

The strength properties of 60C2A are determined by the heat treatment modes performed. Since the interest is in the performance characteristics of the parts, the article does not discuss the performance of steel in castings. They are of practical interest only for technologists of large metalworking enterprises engaged in the production of rolled metal.

Here we will consider the strength indicators of commercial steel in the form of a circle and a strip.

As already mentioned in the general description of the 60C2A brand, optimal performance is achieved by quenching in oil and subsequent tempering in order to relieve internal stresses.

Round steel after quenching and tempering has a tensile strength of 12.7 kg/sq. mm, proof strength 11.7 kg/sq. mm. The proximity of the yield point to the tensile strength indicates the high elastic properties of steel.

The endurance limit of 60C2A with a symmetrical tensile cycle is 49 kg/sq. mm, torsion 29.5 49 kg/sq. mm.

To understand the meaning of these numbers, it is worth remembering that the tensile strength of steel 3 is about 37 kg/sq. mm.

TEST METHODS

4.1. The chemical composition of steel is carried out according to GOST 22536.0 - GOST 22536.5, GOST 22536.7 - GOST 22536.9, GOST 22536.14, GOST 28473, GOST 12344 - GOST 12352, GOST 12355, GOST 12360 and GOST 18895 or other methods that ensure the necessary accuracy definitions.

4.2. Geometric dimensions and shape are determined by measuring instruments in accordance with GOST 26877, GOST 162, GOST 166, GOST 427, GOST 2216, GOST 3749, GOST 5378, GOST 6507, GOST 7502 and templates according to regulatory and technical documentation or tools and templates certified according to GOST 8.001 or GOST 8.326.

4.1; 4.2. (Changed edition, Amendment No. 5).

4.3. The quality of the rolled surface is checked visually, using surface cleaning if necessary.

It is allowed to use non-destructive testing methods.

4.4. Sampling for mechanical tests - according to GOST 7564 (sample cutting diagram according to option 2).

Sampling from coils for all types of tests is carried out at a distance of at least 1.5 turns from the end of the roll.

4.5. Tensile testing (yield strength, tensile strength, relative elongation, relative contraction) is carried out according to GOST 1497 on samples of five times the length.

(Changed edition, Amendment No. 5).

4.6. Brinell hardness is determined according to GOST 9012. The hardness of trapezoidal and T-shaped strips is measured in the thick section of the strip.

4.7. Determination of the depth of the decarbonized layer is carried out according to GOST 1763.

Trapezoidal and T-profile strips are controlled at the point of greatest thickness.

(Amendment, IUS 1-2000).

4.8. The grain size is determined according to GOST 5639.

Control of the grain size of steel grades 55С2, 55С2А, 60С2, 60С2А may not be carried out provided that the steel complies with the requirements of this standard.

4.9. Hardenability is determined by the end hardening method according to GOST 5657.

4.10. Determination of non-metallic inclusions is carried out according to GOST 1778 (method Sh1 or Sh4).

4.11. To control the macrostructure, mechanical properties and grain size, the use of non-destructive testing methods is allowed.

4.12. The manufacturer is allowed to check the macrostructure, mechanical properties and hardenability on an intermediate billet or long products with a larger cross-section and apply the test results to all profiles of a given heat.

The grain size can be determined during heat control.

4.13. Macrostructure control is carried out according to GOST 10243.

4.14. When the manufacturer uses statistical methods for monitoring hardness and mechanical properties in accordance with normative and technical documentation approved in the established manner, the manufacturer may not carry out the control of hardness and mechanical properties provided for by this standard. The manufacturer guarantees compliance of manufactured products with the requirements of this standard. In arbitration cases and during periodic product quality checks, the control methods provided for in this standard are applied.

4.13; 4.14. (Introduced additionally, Amendment No. 2, 3).

4.15. Methods for monitoring fatigue, elastic limit and microstructure are established by agreement between the consumer and the manufacturer.

(Introduced additionally, Amendment No. 5).

PACKAGING, LABELING, TRANSPORTATION AND STORAGE

5.1. Packaging, labeling, transportation and storage of hot-rolled and forged steel - in accordance with GOST 7566 with addition.

The outer diameter of the skeins should be no more than 1500 mm, the inner diameter - no less than 180 mm.

Packaging, marking, transportation and storage of calibrated rolled products - in accordance with GOST 1051, rolled products with special surface finishing - in accordance with GOST 14955.

(Changed edition, Amendment No. 2, 5).

5.1.1. Products are transported by all types of transport in accordance with the rules for the carriage of goods in force for this type of transport.

The weight of the cargo package should not exceed 10,000 kg for mechanized loading on open vehicles, and 1,250 kg on covered vehicles.

Packaging means - according to GOST 7566.

When transporting two or more cargo packages, the dimensions of which make it possible to arrange a transport package with overall dimensions in accordance with GOST 24597, the packages must be formed into transport packages in accordance with the normative and technical documentation.

(Introduced additionally, Amendment No. 2).

5.2. (Deleted, Amendment No. 5).

PURPOSE OF RENTAL

APPENDIX 1.
(Changed edition, Amendment No. 5).
(Amendment, IUS 1-2000).

Application of grade 60С2А

The scope of use of steel is determined by its properties. Steel 60S2A is widely used for the manufacture of heavily loaded structural elements experiencing alternating loads.

These are various springs, friction discs, Grover washers, spring rings, collets, torsion bars - elastic rods that work in torsion. The latter are found in suspensions of heavy tracked and wheeled vehicles, elastic shafts of multi-threaded gearboxes that transmit high power.