TU 1231-052-07528141-2004
These technical conditions apply to high-precision cold-rolled steel tape and strip made of grade 50KhGFA steel (hereinafter referred to as tape and strip) intended for the manufacture of clutch pressure springs for automobiles.
Examples of conventional designations:
A strip of steel grade 50KhGFA, with increased precision in thickness and width, light (C), with cut edges, annealed, ordinary quality, with dimensions of 3.0 x 240 x 1920 mm:
Strip 50KhGFA - C - 3.0 x 240 x 1920 TU 1231-052-07528141-2004
Steel strip grade 50KhGFA, high precision in thickness and width, light (C), with cut edges, annealed, ordinary quality, size 3.0 x 240 mm:
Tape 50KhGFA - C - 3.0 x 240 TU 1231-052-07528141-2004
1 Technical requirements
1.1 Assortment
1.1.1 The tape and strip are manufactured in the following sizes:
- thickness 3.0 mm;
- width 240 mm.
The strip is produced in a length of 1920 mm.
It is allowed to manufacture strips with a length multiple of 480 mm.
The production of tapes and strips of other dimensions in thickness, width and length is carried out in agreement with the consumer.
1.1.2 The tape and strip are manufactured with maximum deviations:
- by width: ±0.40 mm;
- by strip length: +20.00 mm;
- the difference in thickness of the tape and strip in one cross-section should not exceed 0.03 mm.
1.2 Main parameters and characteristics
1.2.1 The tape and strip are made of steel grade 50KhGFA with a chemical composition according to Table 1.
Table 1 In percentage
| C | Si | Mn | Cr | V | Ni | Cu | S | P |
| no more | ||||||||
| from 0.48 to 0.55 | from 0.17 to 0.37 | from 0.60 to 0.90 | from 0.95 to 1.20 | from 0.15 to 0.25 | 0.25 | 0.20 | 0.025 | 0.025 |
| Note - Permissible deviations in the chemical composition of the strip must not exceed the requirements of GOST 14959. | ||||||||
| TU 1231-052-07528141-2004 | ||||||||||
| Change | Sheet | Doc. No. | Subp. | Date | ||||||
| Developer. | Suprunov | 15.03.04 | STEEL TAPE AND STRIP COLD ROLLED INCREASED PRECISION STEEL STAMPS 50 HGFA TECHNICAL SPECIFICATIONS |
Lit. | Sheet | Sheets | ||||
| Checked | Varichev | A | 3 | 8 | ||||||
| JSC "Nytvа" | ||||||||||
| N. counter. | Ryabova | 13.04.04 | ||||||||
| Approved. | ||||||||||
1.2.2 The tape and strip are supplied in annealed condition.
1.2.3 The tape is supplied in rolls with the following parameters:
- internal diameter 500 ± 20 mm;
- maximum outer diameter 1100 mm;
- minimum roll weight 500 kg.
1.2.4 The strips are supplied in packs weighing up to 4000 kg, but not less than 500 kg each.
1.2.5 The value of warping (grooving) of the tape and strip should not exceed 3.0 mm. The waviness of the strip should not exceed 5 mm, the number of waves should not exceed two per 1 meter of length.
1.2.6 The crescent shape of the tape and strip must not exceed 2 mm per 1 m of length.
1.2.7 The tape and strip in the delivered condition must have a microstructure of granular perlite. The grain size of granular perlite is no larger than 8 points on scale 2 of GOST 8233. The presence of lamellar perlite up to 30% on scale 9 of GOST 8233 is allowed.
1.2.8 Non-metallic inclusions of all types must not be larger than 3 points according to GOST 1778.
1.2.9 The total depth of one-sided decarburization of the tape and strip should not exceed 0.03 mm.
1.2.10 The surface of the tape and strip must be light. There must be no film, rolled scale, or rust on the surface of the tape and strip.
The presence of small scratches, marks, and roller marks is allowed in quantities of no more than five pieces per 1 meter of length, up to 0.02 mm deep, and up to 8 mm long.
1.2.11 Delamination at the edges of the tape and strip and bending of the edges are not permitted.
1.2.12 The macrostructure of the steel must not have any traces of shrinkage cavities, bubbles, delamination, cracks, or foreign inclusions.
1.2.13 The mechanical properties of the tape and strip must comply with the requirements specified in Table 2.
Table 2
| Tensile strength, σ B , N/mm 2 | Relative elongation, δ 4 , % | Hardness HRB, not more than |
| 500 - 630 | not less than 20 | 95 |
1.3 Marking
1.3.1 Marking of tape and strip is carried out in accordance with Section 4 of GOST 7566.
1.4 Packaging
1.4.1 Packaging of tape and strips is carried out in accordance with Section 5 of GOST 7566.
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2 Safety requirements
2.1 The manufacturer guarantees the safety of life and health of consumers of the tape and strip and the protection of the environment, provided that the tape and strip are used for their intended purpose.
2.2 The tape and strip do not release harmful chemicals into the environment and do not have a harmful effect on people.
3 Acceptance Rules
3.1 Rules for acceptance of tape and strip according to section 3 of GOST 2283.
4 Control methods
4.1 The quality of the surface and edges of the tape and strip is checked by visual inspection without the use of magnifying devices. The quality of the surface and edges is checked on the second turn of the roll.
To check the quality of the surface and edges of the strips, three strips are selected, one from each of the upper, middle and lower parts of the pack.
4.2 Hardness testing is carried out in accordance with GOST 9013.
4.3 Microstructure control is performed on samples measuring 30 x 40 mm, according to the scales of GOST 8233.
4.4 Tensile testing is carried out in accordance with GOST 11701 on samples with a calculated length of 4B 0 (at B 0 = 20 mm).
4.5 The non-flatness of the tape and strip is determined according to GOST 26877.
4.6 The camber is checked by aligning the edges of a 1 m long tape or strip sample with a verification ruler of the ЩД 2-1000 type according to GOST 8026. The measurement is carried out at the point of greatest curvature with a ruler according to GOST 427.
4.7 The size of the decarburized layer is determined using method M of GOST 1763.
4.8 The sampling method for determining the chemical composition of steel must comply with the requirements of paragraph 3.4 of GOST 7565.
4.9 The chemical composition is determined in accordance with the requirements of GOST 12344, GOST 12345, GOST 12346, GOST 12347, GOST 12348, GOST 12350, GOST 12351, GOST 12352, GOST 12355, GOST 27809, GOST 18895 and in accordance with the requirements of GOST 28743 or other methods that ensure the required accuracy of determination.
4.10 Control of the macrostructure of the surface of the tape and strip is carried out by the etching method in accordance with GOST 10243.
5 Transportation and storage
5.1 Transportation and storage of tape and strip is carried out in accordance with Section 6 of GOST 7566.
6 Manufacturer's Warranties
6.1 The manufacturer guarantees that the tape and strip comply with the requirements of these technical conditions, subject to the rules of transportation and storage.
6.2 The warranty period is six months from the date of shipment of the tape and strip to the consumer.
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List of reference documents
| Document designation | The number of the sheet where the reference is located | Note |
GOST 427-75 GOST 1763-68 GOST 1778-70 GOST 2283-79 GOST 7565-81 GOST 7566-94 GOST 8026-92 GOST 8233-56 GOST 9013-59 GOST 10243-75 GOST 11701-84 GOST 12344-88 GOST 12345-2001 GOST 12346-78 GOST 12347-77 GOST 12348-78 |
5 Measuring metal rulers. Technical conditions. 5 Steel. Methods for determining the depth of the decarburized layer. 4 Steel. Metallographic methods for determining non-metallic inclusions. 5 Cold-rolled strip made of tool and spring steel. Technical conditions. 5 Cast iron, steel and alloys. Method of sampling for determination of chemical composition. 4.5 Metal products. Acceptance, marking, packaging, transportation and storage. 5 Verification rulers. Technical conditions. 4.5 Steel. Microstructure standards. 5 Metals. Rockwell hardness test method. 5 Methods of testing and evaluation of macrostructure. 5 Metals. Method of tensile testing of thin sheets and strips. 5 Alloyed and high-alloy steels. Methods for determining carbon. 5 Alloyed and high-alloy steels. Methods for determining sulfur. 5-Alloyed and high-alloy steels. Methods for determining silicon. 5 Alloyed and high-alloy steels. Methods for determining phosphorus. 5 Alloyed and high-alloy steels. Methods for determining manganese. |
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List of reference documents
| Document designation | The number of the sheet where the reference is located | Note |
GOST 12350-78 GOST 12351-81 GOST 12352-81 GOST 12355-78 GOST 14959-79 GOST 18895-97 GOST 26877-91 GOST 27809-95 GOST 28743-93 |
5 Alloyed and high-alloy steels. Methods for determining chromium. 5 Alloyed and high-alloy steels. Methods for determining vanadium. 5 Alloyed and high-alloy steels. Methods for determining nickel. 5 Alloyed and high-alloy steels. Methods for determining copper. 3 Rolled products from spring carbon and alloy steels. Technical conditions. 5 Steel. Photoelectric analysis method. 5 Metal products. Methods of measuring shape deviation. 5 Cast iron and steel. Methods of spectrographic analysis. 5 Solid mineral fuel. Methods for determination of nitrogen. |
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