GOST 27450-87
GOST 27450−87 (ST SEV 5730−86) Tube of copper and copper-zinc alloys. Method of determining contamination of the inner surface
GOST 27450−87
(ST CMEA 5730−86)
Group В69
STATE STANDARD OF THE USSR
TUBE OF COPPER AND COPPER-ZINC ALLOYS
Method of determining contamination of the inner surface
Tubes of copper and copper-zinc alloys. Method for determination of impurity of inner surface
AXTU 1809
Valid from 01.01.89
before 01.01.94*
________________________________
* Expiration removed
Protocol N 3−93 Interstate Council
for standardization, Metrology and certification
(IUS No. 5/6, 1993). — Note the manufacturer’s database.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
PERFORMERS
Y. M. Leybov, A. I. Vorobyov
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from
3. The standard fully complies ST SEV 5730−86
4. INTRODUCED FOR THE FIRST TIME
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
Item number |
| GOST 6265−74 |
1 |
| GOST 9976−83 |
1 |
| GOST 20015−74 |
1 |
| GOST 20288−74 |
1 |
This standard specifies a method for determining contamination weighing up to 0.5 g per unit area or length of the inner surface of tubes of copper and copper-zinc alloys.
The method consists in passing an organic solvent through the tubes to dissolve the dirt channel, evaporation of solvent, weighing of sediment contamination and in terms of its mass per unit area or length.
1. EQUIPMENT AND REAGENTS
A glass with a capacity of 250 cm.
Beaker for collecting solvent with a capacity from 50 to 100 cm.
The pump vacuum.
Drying Cabinet.
Desiccator with desiccant.
Scales with a weighing error of 1x10g.
Organic solvents purity h. d. a.
Carbon tetrachloride according to GOST 20288−74.
Chloroform according to GOST 20015−74*.
______________
* On the territory of the Russian Federation GOST 20015−88. — Note the manufacturer’s database.
Trichloroethylene according to GOST 9976−83* or ethyl ether according to GOST 6265−74.
______________
* On the territory of the Russian Federation GOST 9976−94. — Note the manufacturer’s database.
Tool with a scale division of 1 mm.
2. METHOD OF SAMPLING AND PREPARATION OF SAMPLES
2.1. Place of selection and the number of core samples establish normative-technical documentation for specific types of products.
2.2. For the test cut samples with a length of 2.5 to 3.0 m.
2.3. The outer surface of the samples at the ends should be degreased.
3. TESTING
3.1. Installation for testing is shown in the drawing.
The test sample connect the 2 via the gasket 3 with sleeps 6 in which is placed a weighted Cup 5.
The other end of the tube is dipped into the Cup 1 with the solvent.
3.2. Through a tube flow the solvent in an amount of not less than 30 cm. If necessary, the solvent is sucked into the sample by means of a pump through the pipe 4.
3.3. Passed through the sample, the solvent collected in the Cup 5. The solvent in the beaker was evaporated in a fume hood in a water bath at the boiling point of the solvent (without spraying), then dried in a drying Cabinet at a temperature of 100 to 110 °C for 10 min.
A glass of dry residue cooled in a desiccator for 30 min and weighed.
4. PROCESSING OF THE RESULTS
4.1. A lot of pollution (a) in grams is calculated by the formula
where is the mass of the beaker with the sediment, g;
— the mass of the beaker with no sediment,
4.2. A lot of dirt (sample) in grams per square meter of inner surface is calculated by the formula
where is the internal surface area of the specimen, m
.
4.3. A lot of pollution (a) in grams per meter length of the sample is calculated by the formula
where is the length of sample, m
