Form number 665−1
ALLOY TAPES AND STRIPES
CHROMEL AND ALUMEL
(instead of TU1−5-025−77)
Valid from 01/01/83
until 01.01.88, 93 (2), 98 (3) (no limitation avg. e) (2)
Head of Department
These technical conditions apply to strips and strips of chromel and alumel alloys, intended for the manufacture of connecting tips for thermocouples and compensation wires.
An example of a conventional designation of a strip made of chromel alloy with a thickness of 1.0 mm supplied according to TU1−805−045−82:
Chromel ribbon 1.0 TU1−805−045−82.
1. TECHNICAL REQUIREMENTS
1.1. The dimensions of the tapes and strips and the maximum dimensional deviations must comply with the requirements of table. 1.
|Thickness||Maximum deviation in thickness||Width||Length not less|
1.2. The chemical composition of chromel and alumel alloys must meet the requirements of GOST 492−73
1.3. Tapes and strips are made from rolled oval section with dimensions 15x50x500 mm supplied according to TU 48−21−63−72.
1.4. Tapes and strips are delivered annealed.
1.5. The surface of tapes and strips must be flat, smooth and free from cracks and delamination. On the surface of tapes and strips, defects are allowed that do not lead the tape or strip beyond the maximum deviation in thickness. An oxidized surface and traces of burnt-out grease on belts and strips are not a rejection sign.
1.6. Tapes and stripes should be cut on all sides. Sickle and warped ribbons and stripes are not a rejection sign.
1.7. Indicators of mechanical properties of tapes and strips must comply with the requirements of table. 2.
|Alloy grade||Ultimate tensile strength σ in, MPa (kgf / mm 2)||Elongation, δ,%|
2. RULES OF ACCEPTANCE
2.1. Strips and strips of chromel and alumel alloys are presented and accepted in batches.
The party must be assembled from strips and strips by alloys and of the same class, similar to the kitting of the rolling stock.
2.2. Chemical analysis of chromel and alumel alloys is carried out at the supplier of rolled products.
2.3. Each tape and strip is subject to dimensional control.
2.4. The surface quality is checked on every belt and strip.
2.5. For the control of mechanical properties, two samples are taken from a batch of each alloy.
2.6. If unsatisfactory test results are obtained, a second test is carried out on a double number of samples cut from the same tapes and strips.
Upon receipt of unsatisfactory results of repeated tests, obtained on at least one of the samples, the tapes and strips are subjected to piecewise testing.
3. TEST METHODS
3.1. Chemical analysis of finished tapes and strips is not performed. The conformity of the chemical composition of the alloys is guaranteed by the manufacturer of the rolled stock.
3.2. Inspection of the surface of tapes and strips is carried out without the use of magnifying devices.
3.3. The dimensions are checked with a measuring tool that ensures the required measurement accuracy.
3.4. Tensile testing of tapes and strips is carried out in accordance with GOST 1497−78 84. (1)
3.4.1. The shape and dimensions of the samples are set in accordance with GOST 1497−78 84. (1)
The estimated length of the sample is calculated by the formula:
— calculated length of the sample, mm;
design sample length, mm 2 .
4. MARKING, PACKAGING, DOCUMENTATION, TRANSPORTATION AND STORAGE
4.1. Each tape or strip must be marked with indelible paint in letters:
X — for chromel;
A — for alumel and the corresponding number for each alloy, for example: X3 or A3.
4.2. A lot of tapes and strips of the same alloy and class must be rolled up, tied with soft wire or other tape made of non-ferrous alloys and wrapped in moisture-proof paper and burlap.
Delivery of strips in bundles is allowed.
4.3. A tag is attached to each roll or bundle, which should indicate:
b) grade of alloy;
c) batch number;
d) number of technical conditions;
e) the stamp of the technical control department;
4.4. Each batch of tapes and strips is accompanied by a certificate certifying the conformity of the quality of tapes and strips to the requirements of these specifications, which indicates:
a) the name of the manufacturer;
b) grade of alloy;
c) the size of the tapes and stripes;
d) batch number;
e) the mass of the batch;
f) the number of seats in the party;
g) the results of mechanical tests;
h) designation of these technical conditions.
4.5. Transportation of belts and strips is carried out by rail in covered vehicles in accordance with the «Technical conditions for the carriage and fastening of goods» of the Ministry of Railways of the USSR, publication of 1969, or by road in accordance with the «General rules for the carriage of goods by road» approved by the Ministry of Road Transport of the RSFSR on July 30, 1971 …
4.6. Tapes and strips should be stored in covered warehouses, protected from moisture, active chemicals and mechanical damage.
LIST OF DOCUMENTS WITH REFERENCES IN TU1−805−045−82
GOST 1497−78 84 (1)
p. 3.4, p. 3.4.1
Form 2 GOST 25 …
CHANGE REGISTRATION SHEET
|1||1, 4, 6||Izv. 803 16−26−87|
|2||2||Izv. 803 16−62−88|
|3||1||Izv. 803 2411−92|