GOST 12766.5-90

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  ГОСТ 12766.5-90

GOST 12766.5−90 flattened Strip of precision alloys with high electrical resistance. Specifications (with Amendments No. 1, 2)

GOST 12766.5−90
Group B34

INTERSTATE STANDARD

FLATTENED STRIP OF PRECISION ALLOYS
WITH HIGH ELECTRICAL RESISTANCE

Specifications

Flattened strip of high electric resistance precision alloys.
Specifications

ISS 77.140.50
OKP 12 3600

Date of introduction 1991−01−01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of metallurgy of the USSR

2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on management of quality and standards from 13.02.90 N 196

Change No. 2 adopted by the Interstate Council for standardization, Metrology and certification (Protocol № 7 from 26.04.95)

The adoption voted:

3. REPLACE GOST 12766.5−77

4. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS

5. Limitation of actions taken by Protocol No. 5−94 of the Interstate Council for standardization, Metrology and certification (ICS 11−12−94)

6. EDITION with Amendments No. 1, 2, adopted in may 1992, February 1996 (IMS 8−92, 5−96)


This standard covers rolled strip of precision alloys with high electrical resistance for the manufacture of heating elements and resistance elements.

1. TECHNICAL REQUIREMENTS

1.1. Crimped ribbon must be manufactured in accordance with the requirements of this standard.

1.1.1. The tape is divided:

for permissible deviation of electric resistance of 1 m of tape:

usual quality — 1;

high quality PC;

for normalized values:

with a normalized elongation;

without standardization of elongation.

1.2. Basic parameters and dimensions

1.2.1. Crimped ribbon made from alloys of H15N60, H15N60-H, CR20NI80, CR20NI80-N with a thickness of 0.1−1.0 mm, width 0.5−5.0 mm.

1.2.2. Dimensions and limit deviations of the rolled strip should correspond to GOST 10234. Maximum deviations in thickness should be bilateral symmetry with field tolerance to the norms of GOST 10234, normal accuracy in thickness. Maximum deviations in width according to GOST 10234 for normal accuracy.

1.2.3. Camber strips shall not exceed 15 mm per 1 m Standards optional to 01.01.96. Definition of necessary.

Examples of symbols

Flattened strip with a thickness of 0.3 mm, a width of 2.5 mm, the usual quality of alloy grade H15N60:

Tape square 0,3x2,5−1-H15N60 GOST 12766.5−90

The same thickness of 0.2 mm wide by 1.0 mm high quality with a normalized elongation of alloy grade CR20NI80-H:

Tape the square of 0.2−1.0-PC-AND-CR20NI80-H GOST 12766.5−90

(Changed edition, Rev. N 1).

1.3. Features

1.3.1. The ribbon made in soft annealed condition.

1.3.2. The chemical composition of the alloys of H15N60, H15N60-H, CR20NI80, CR20NI80-H should correspond to GOST 10994.

1.3.3. Nominal electrical resistivity for crimped alloy ribbon H15N60, H15N60-H — 1,18 μω·m, alloys CR20NI80, CR20NI80-H — 1.17 μω·m.

Note. Rules are not a sign of rejection to 01.01.96. Definition of necessary.


(Changed edition, Rev. N 1).

1.3.4. Permissible deviation from the nominal values of the electrical resistivity shall not exceed ±5%.

1.3.5. Permissible deviation from the nominal electrical resistance of 1 m of tape shall not exceed 10% for ribbons of high quality and 14% for tapes of ordinary quality.

1.3.6. The variation of electrical resistance up to 1 meter of ribbon within the spool (mandrel) should not exceed 4%.

1.3.7. Survivability by the method G of alloys of H15N60-H and CR20NI80-H with test temperatures of 1150 °C and 1200 °C must be at least 150 and 160 h, respectively.

(Changed edition, Rev. N 2).

1.3.8. (Deleted, Rev. N 2).

1.3.9. The surface of the rolled strip should be free of captivity, cracks, and dross; must be one of defects such as nicks, fingerprints, scratches, scratches and some small prisoner, not bringing the ribbon over the limit deviation on thickness.

The surface should be dark gray, gray, or covered with a thin oxide film tint. At the customer’s request the surface of the tape shall conform to the models agreed upon in the prescribed manner.

1.3.10. The condition of the edges of the rolled strip should correspond to GOST 10234.

1.3.11. At the request of the consumer tape is manufactured with a relative elongation of at least 20%.

1.3.12. Correction factors for calculating changes in electrical resistance depending on temperature is given in Appendix 1; the physical, the mechanical properties of the alloy and the maximum operating power and temperature are given in appendices 4−6ГОСТ 12766.1.

1.4. Marking

1.4.1. Labeling — according GOST 7566.

1.4.2. Transport marking under GOST 14192.

1.5. Packaging

1.5.1. Packaging — according to GOST 7566 with additions.

1.5.1.1. Coil or mandrel should be wrapped in paper according to GOST 9569, 16711или GOST GOST 8828 Packed tight in rows in boxes of types I or II according to GOST 2991, lined inside with waterproof paper according to GOST 8828 or other regulatory-technical documentation. Packaging in barrels, containers or other metal container according to normative-technical documentation, developed in accordance with the requirements of GOST 6247, GOST 15102, GOST 18477 and GOST 26155.

Between the rows of coils are laid cardboard according to GOST 7376 or other regulatory-technical documentation.

Weight of cargo must not exceed 80 kg.

1.5.1.2. Crimped tape should be wound on a reel or mandrel separatornyi rows and to provide free spooling.

Allowed winding on the coil or mandrel is not more than three of the segments of one party. Segments must be separated by spacers, protecting tape from entanglement.

2. ACCEPTANCE

2.1. The ribbon take parties.

The party must consist of one metal bottoms, same size and must be issued a document about quality that contains:

trademark or name or the name and trademark of manufacturer;

symbol;

the results of the tests;

the chemical composition of the alloy.

2.2. To determine the quality of the rolled tape from the party is taken to control the size and surface quality — 100% production to control the variation of electric resistance of 1 m within the same reel (mandrel) — one spool (mandrel);

to control the electrical resistivity single coil (coil, bar);

to control elongation, electrical resistance of 1 m and camber — three spool (mandrel);

to control chemical composition — one sample from the melt;

to control survivability — a single sample of weight, enough to make at least 5 m wire diameter: 0.8 mm;

2.3. Control of the variation of electrical resistance of 1 m within the same reel (mandrel) and camber the manufacturer conducts periodic, at least once a year.

2.4. The alloy’s chemical composition is certified by a document of quality issued by the company, smelting the metal.

2.5. The test of survivability according to the method G is carried out periodically, but not less than once per year.

(Changed edition, Rev. N 2).

2.6. If unsatisfactory test results of at least one indicator of a re-test is carried out according to GOST 7566.

3. CONTROL METHODS

3.1. Sampling for chemical analysis is carried out according to GOST 7565.

Chemical composition of alloys determined according to GOST 12344 — 12348 GOST, GOST 12350, 12352 GOST, GOST 12356, 12357 GOST, GOST 12364, 12365 GOST, GOST 28473 or other methods providing the required accuracy of the analysis.

3.2. The dimensions of the rolled strip is measured with a micrometer according to GOST 6507 or other instruments providing the required measurement accuracy.

3.3. Camber 1 m of the tape is determined according to GOST 26877.

Allowed to measure the camber strip thickness of 0.3 mm or less, and a width of 2.0 mm or less at a sample length of 100 mm, and the camber should be no more than 3.0 mm.

3.4. The surface quality is checked visually.

If necessary, the depth of the defects is determined by the sweep. The location of the defect is cleaned with sandpaper to remove the defect with subsequent comparative measurement in the stripped and unstripped areas. If you cannot determine defect depth sweep depth of the defect is determined by metallographic method.

3.5. Electrical resistance up to 1 meter of tape and wire before the crimp is determined according to GOST 7229 with the use of instruments of accuracy class not worse than 0,05.

The nominal value of the electrical resistance of a 1 m strip () Ω, calculated by the formula

,

where  — the nominal value of the electrical resistivity of the rolled tape, μω·m;

 — length of specimen, m;

the nominal cross-sectional area of the rolled strip, is determined in compliance with GOST 10234, m.

3.6. To determine the variation of electrical resistance of 1 m within the spool (mandrel) to measure the electric resistance of 1 m of tape at the beginning and end of the spool (mandrel) and the difference between them relates to the arithmetic mean of the obtained values.

3.7. Electrical resistivity of the rolled strip () μω·m, is calculated by the formula

,

where is the actual electrical resistance of 1 m of the rolled tape, Ohm;

the actual cross — sectional area of the rolled tape, m;

 — the length of the specimen rolled strips, M.

Allowed to determine the electrical resistivity on the wire before flattening in heat-treated according to the method GOST 12766.1.

3.8. Elongation is determined according to GOST 11701, on samples with an estimated length of 50 mm.

3.9. The definition of survivability is carried out according to GOST 2419, method G to burnout.

(Changed edition, Rev. 2).

3.10. For each type of test should be taken one sample from each selected spool (mandrel).

4. TRANSPORTATION AND STORAGE

4.1. Transport according to the GOST 7566 with additions.

4.1.1. Transportation must be carried out by all kinds of transport in covered vehicles in accordance with cargo carriage regulations applicable to transport of this form, and the technical conditions of loading and fastening of cargoes, approved by the Ministry of Railways of the USSR.

4.1.2. Storage conditions for up to 1 month — SGS according to GOST 15150, for more than 1 months — 1L churchyard 15150.

4.1.3. When you ship two or more packages to one user to carry out consolidation packages in accordance with GOST 24597 and GOST 21650.

5. MANUFACTURER’S WARRANTY

The manufacturer guarantees product compliance with the requirements of this standard while complying with the storage conditions.

Warranty period of storage — 3 years from date of manufacture.

APPLICATION (reference). CORRECTION FACTORS FOR CALCULATING CHANGES IN ELECTRICAL RESISTANCE DEPENDING ON TEMPERATURE

APP
Reference

Note. The electrical resistance at room temperature () was determined for each alloy after heating the sample to temperatures above 600 °C and cooling with the furnace. In this case, the electric resistance () above regulated in this standard: for grades H15N60, H15N60-H — 3%, for alloy grade CR20NI80-H — 5%.



The text of the document is verified by:
the official publication of the
Steel quality and high quality.
Bars and shapes, calibrated
steel. Part 3: Sat. Standards. -
M.: IPK Publishing house of standards, 2004