GOST 21877.0-76
GOST 21877.0−76 Babbit tin and lead. General requirements for methods of analysis (with Amendments No. 1, 2)
GOST 21877.0−76
Group B59
STATE STANDARD OF THE USSR
BABBIT TIN AND LEAD
General requirements for methods of analysis
Tin and lead babbits. General requirements for methods of analysis
AXTU 1709*
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* Introduced advanced Edit. N 2.
Valid from 01.01.78
to 01.01.83*
_______________________________
* Expiration removed
according to the Protocol of the Intergovernmental Council
for standardization, Metrology and certification
(IUS N 2, 1993). — Note
manufacturer database.
DEVELOPED by the Central research Institute for tin industry (Tsniiolovo)
Director V. A. Arsenico
Supervisor S. V. Meshkov
Executor G. V. Ivanova
INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
Zam. Minister N.N. Chepelenko
The draft all-Union scientific research Institute of standardization (VNIIS)
Director A. V. Gichev
APPROVED AND promulgated by the Decree of the State Committee of standards of Ministerial Council of the USSR from may 24, 1976 N 1264
REPLACE GOST 1380.0−70
The Change N 1, approved and put into effect by the Decree of the USSR State Committee for standards from
Change N 1, 2 made by the manufacturer of the database in the text N 6 ICS 1983 ICS N 10 1987
1. This standard applies to tin and lead babbits according to GOST 1320−74 and establishes General requirements for methods of analysis.
(Changed edition, Rev. N 2).
2. The analysis is carried out on the samples taken according to GOST 1320−74.
3. For the preparation of solutions and tests used distilled water according to GOST 6709−72.
4. The used reagents must be of «chemically pure» (hç). In the absence of H. h. reagents use the reagents purity «pure for analysis» (h. e. a.).
(Changed edition, Rev. N 1).
5. Under the concentration in body-weight percentage should understand the amount of solute in grams per 100 ml of solution.
6. In the expression «diluted 1:1, 1:2», etc. the first digits indicate the volume of the acid, or any solution, the second volume of the water. The expression «hot water (a solution)» means that the liquid has a temperature of 60−70 °C and «warm water (solution)» is 40−50 °C.
(Changed edition, Rev. N 1).
7. Weighing of batches produced with the maximum error of 0.0002 g.
8. Measuring laboratory glassware: pipettes, burettes, volumetric flasks, etc. should not be below 2 accuracy class according to GOST 1770−74 and GOST 20292−74*.
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* On the territory of the Russian Federation there are 29169−91 GOST, GOST 29227−91−29229−91 GOST, GOST 29251−91-GOST 29253−91. — Note the manufacturer’s database.
(Changed edition, Rev. N 1).
9. In each series of definitions needs to conduct at least three control experiments in terms of analysis. The average value of them is an appropriate amendment in the result of analysis of the sample.
10. The mass concentration of the standard solutions set no less than three batches of a standard substance. The mass concentration expressed in grams of element per millimeter of solution and calculate with accuracy to the third decimal place. The purity of the metals used for the preparation of standard solutions needs to be not less than 99.9%.
(Changed edition, Rev. N 1, 2).
11. The analysis photocolorimetric method, the cell is chosen so that the measurements were carried out at the optimum optical density for the corresponding colored connections and this device.
11.1. The calibration graphs are built in the system of rectangular coordinates, plotting on the abscissa the content of the element in grams, and y-axis are the corresponding measured values of optical density.
12. The contents of the element find in three batches. The arithmetic mean of the results of the three definitions accepted for the final result. The maximum difference between the extreme results of the analysis at a confidence level of 0.95 does not exceed the permissible differences for the corresponding concentration range of the element. When the divergence of the results of the analysis more acceptable, determining repeat.
(Changed edition, Rev. N 1, 2).
13. Control the correctness of the results in the analysis of tin and lead is performed using:
standard samples certified mixtures prepared in the form of powders or solutions; standard additives.
13.1. Standard samples and certified mixtures are analyzed simultaneously with the investigated samples from the same number of analysis results. The contents of the analyzed element in the standard samples and certified mixtures should not exceed its content in the sample more than twice.
13.2. When the verification of results using standard samples and certified mixtures analysis of the investigated samples are considered correct if the following condition is: the deviation of the reproduced values of element content in the standard samples and certified mixtures from introduced should not exceed half the allowable differences specified by the standard.
13.3. The analysis of the sample with the additive is carried out simultaneously with the sample containing no additives, of the same date the results of the analysis.
13, 13.1−13.3. (Changed edition, Rev. N 2).
13.4. Calibration curve for determining the element being measured according to the method, the accuracy of the results is checked by using standard addition must be straight and pass through the origin.
13.5. When checking using the standard addition analysis of the investigated samples are considered correct if the following conditions are met:
where — the average result of the determination of the content of the analyzed element in the sample without additives, %;
— the average result of the determination of the content of the analyzed element in the sample with additive, %;
— contents of the analyzed element in additive, %;
— the permissible variation for the found contents of the analyzed element in the sample without additives established by the standard, %;
— the permissible variation for the found contents of the analyzed element in the sample with additive, %;
If you 
where — the permissible variation for found contents specified by the standard, %.
13.6. Failure to comply with the conditions specified in the PP.13.2 and 13.5, a second analysis of standard samples and certified mixtures or samples with the additive and without the additive. If a deviation from an established level of correctness is confirmed, the results of the analysis of the investigated samples are considered improper and subject to re-analysis at which execution should be identified and eliminated the causes of deviations from specified level of correctness.
(Changed edition, Rev. N 2).
14. Safety requirements — according to normative-technical documentation approved in the established order.
13, 13.1−13.6, 14. (Introduced later, Rev. N 1).
