GOST 7221-80

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  ГОСТ 7221-80

GOST 7221−80 Strips of gold, silver and their alloys. Technical specifications (with Changes 1−3 N)

GOST 7221−80

Group В53

INTERSTATE STANDARD

STRIPS OF GOLD, SILVER AND THEIR ALLOYS

Specifications

Strips out of gold, silver and their alloys. Technical conditions

ISS 39.060
GST 18 6000

Date of introduction 1983−01−01

INFORMATION DATA

1. DEVELOPED by the Ministry of nonferrous metallurgy of the USSR

2. INTRODUCED by the Ministry of nonferrous metallurgy of the USSR

3. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from 21.05.80 N 2260

Change No. 3 adopted by the Interstate Council for standardization, Metrology and certification (Protocol No. 24 dated 5 December 2003).

For the adoption of the changes voted by national standardization bodies of the following States: AM, BY, KG, MD, RU, TJ, TM, UA [codes alpha-2 at MK (ISO 3166) 004]

4. REPLACE GOST 7221−54

5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS

6. Limitation of actions taken by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)

7. EDITION (April 2005) with Amendments No. 1, 2, 3, approved in June 1987, February 1993, March, 2004 (I & C 10−87, 1−94, 6−2004), Amendment (ICS 5−2005)

This standard applies to cold rolled strip of gold, silver and their alloys for technical purposes and for jewellery.

(Changed edition, Rev. N 3).

1. ASSORTMENT

1.1. The thickness of the strips and limit deviations must correspond to those in table.1.

1.2. Width, the length of the strips and limit deviations in it depending on thickness shall conform to the requirements specified in table.2.

Table 1

Table 2

Examples of callouts

The strip of alloy grade according to GOST Srm90 6836, solid, thickness 1 mm, width 200 mm, length 500 mm:

Streak SRM 90T 1x200x500 GOST 7221−80

The strip of alloy grade Clsrm 585−80 according to GOST 30649, soft, thickness of 1 mm, width 200 mm, length 500 mm:

Strip Clsrm 585−80M 1x200x500 GOST 7221−80

Allowed in the party random strips of width and length not more than 10% of the batch weight.

(Changed edition, Rev. N 3, Amendment. IUS 5−2005).

2. TECHNICAL REQUIREMENTS

2.1. Stripes shall conform to the requirements of this standard.

The chemical composition of the bands for technical purposes must comply with GOST and GOST 6835 6836, for the jewellery industry — standard 30649.

(Changed edition, Rev. N 3).

2.2. Bands shall be manufactured in soft (annealed) and hard (unannealed) condition.

2.3. The surface bands must be pure, without captivity, cracks, delaminations, no signs of grease. On the surface of the bands allowed individual surface defects (dents, scratches, punctures, traces of Stripping and sabrosky), if they control the sweep display no bands for the limit deviation on thickness.

Allowed local darkening and color tint.

2.4. Strips should be trimmed evenly and should not have ragged edges.

2.5. Mechanical properties of strips specified in the application.

2.6. The properties of the alloys jewelry destination specified in GOST 30649.

(Added, Rev. N 3).

3. ACCEPTANCE RULES

3.1. Stripes take parties. The party should consist of strips of the same brand, same bottoms, same size, same condition of material and is decorated with one a quality document in which you specify:

— trademark or name of the manufacturer;

— brand material;

— the size of the band;

— the condition of the material of the strips;

— chemical composition;

— the batch number;

— a lot of bands in grams;

— date of issue;

stamp of technical control of the manufacturer;

— the designation of this standard.

3.2. Quality control strips for compliance with the requirements of paragraphs.1.1; 1.2; 2.3; 2.4 should be subjected to not less than 25% of the bands of the party, but not less than three bands.

3.1, 3.2. (Changed edition, Rev. N 1).

3.2. Checks weight of each packing unit is held in the balance according to GOST 24104, in accordance with the order of accounting and storage of precious metals, established by the appropriate national authority.

3.3. To check the chemical composition for compliance with GOST 6835, GOST GOST 6836или 30649 user selects one strip from the party, the manufacturer determines the chemical composition of the sample, selected from each heat.

3.2 and 3.3. (Changed edition, Rev. N 3).

3.4. If unsatisfactory test results of at least one of the indicators it is carried out a re-test at twice the sample or the sample taken from the same batch.

The results of repeated checks apply to the entire party.

4. TEST METHODS

4.1. The thickness of the strips is measured at a distance of not less than 25 mm from the vertex of the angle and not less than 15 mm from the edge of the micrometer according to GOST 6507. Measurement shall be both ends.

The width and length of strips to measure metal ruler according to GOST 427.

(Changed edition, Rev. N 1, 2).

4.2. The test strips for compliance with the requirements of PP.2.3 and 2.4 conduct visual inspection without the use of magnifying devices.

4.3. Determination of the chemical composition is carried out according to GOST 27973.0 — 27973.3 GOST, GOST 28353.0 — 28353.3 GOST, GOST 16321.1, GOST 16321.2, 17234 GOST, GOST 22864 or other methods providing the required accuracy.

If there is disagreement in the assessment of the chemical composition chemical composition is determined by GOST 27973.0 — 27973.3 GOST, GOST 28353.0 — 28353.3 GOST, GOST 16321.1, 16321.2 GOST, GOST 17234, 17235 GOST and GOST 22864.

(Changed edition, Rev. N 1, 2).

5. MARKING, PACKAGING, TRANSPORTATION AND STORAGE

5.1. On the corner of each strip is marked, containing: the material grade, batch number, trademark of the manufacturer.

5.2. Packs of strips wrapped with paper according to GOST 8273, placed in boxes made according to normative-technical documentation, or between the plywood strips, wrapped with paper according to GOST 8273 and Packed in cloth bags.

Allowed to apply for the packaging of other equivalent materials that do not impair product quality.

5.3. On each bag (box) attached label:

cost of the package;

— the name of the consumer;

— weight;

— gross mass;

numbers of the parcel;

— the numbers of the registry;

index warehouse-packer;

— the name of the manufacturer.

5.2, 5.3. (Changed edition, Rev. N 1).

5.4. The gross mass of the packing space should not exceed 10 kg.

5.5. Bags (boxes) must be sealed by the manufacturer.

(Changed edition, Rev. N 1).

5.6. Strips should be stored in a heated room, not in the atmosphere containing sulfur compounds, under conditions that protects the strip from contamination and mechanical damage.

5.7. When transporting the strips must be protected from moisture, mechanical damage and corrosive environments.

5.8. Storage and transportation strips of gold, silver and their alloys is carried out in the manner prescribed for storage and transportation of precious metals.

(Changed edition, Rev. N 1).

APPLICATION (reference). THE HARDNESS OF THE BANDS OF GOLD, SILVER AND THEIR ALLOYS

APP
Reference

Hardness test was carried out on strips with thickness of 1.0 mm.

APP. (Changed edition, Rev. N 3).