GOST 1219.2-74
GOST 1219.2−74 calcium Babbits. Method of determination of sodium (Change No. 1)
GOST 1219.2−74
Group B59
INTERSTATE STANDARD
CALCIUM BABBITS
Method of determination of sodium
Lead-calcium bearing alloys.
Method for determination of sodium content
ISS 77.160.20*
____________________
* In the index «National standards» 2006
ISS
Date of introduction 1975−01−01
The decision of the State standards Committee of the Council of Ministers of the USSR from January 17, 1974 N 150 date of introduction is established 01.01.75
Limitation of actions taken by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)
REPLACE GOST 1219−60 in part of sec. III
EDITION (September 2003) with amendment No. 1, approved in November 1979 (ICS 1−80).
This standard applies to calcium babbits and sets the volume of the acid-basic method for the determination of the sodium content (in mass fraction of sodium from 0.20 to 1.0%).
The method is based on neutralization of sodium carbonate with sulfuric acid in the presence of the indicator methyl orange.
To transfer sodium hydroxide a sample of the Babbitt oxidize when heated in a muffle furnace, and then leached oxides with water. Preventing the determination of the alloy components are separated by precipitation with carbon dioxide.
(Changed edition, Rev. N 1).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1219.0−74.
2. APPARATUS, REAGENTS AND SOLUTIONS
Muffle furnace of any type, thermocouple.
Pumps porcelain rectangular N 2 according to GOST 9147−80 or No. 3 according to GOST 9147−80.
A balloon with carbon dioxide (or apparatus Kippa).
Sulfuric acid, 0.1 N. solution; prepared from fixanal.
The indicator methyl orange, 0.1 percent aqueous solution.
Water saturated with carbon dioxide; is prepared as follows: carbon dioxide from a cylinder or apparatus of the Kippa is passed in a bottle of distilled water for 10 min. Saturation effect before applying water.
3. ANALYSIS
A portion of the babbit 4 g is placed in a rectangular porcelain boat, put in a muffle furnace heated to 400−450 °C and kept at this temperature for 15 min. After oxidation the sample boat is removed, cooled and pour contents using a glass rod in a conical flask with a capacity of 250 cm. The boat 2−3 times rinse over the bulb with warm water.
Poured into a flask of 125 cmof hot water and leached by boiling to reduce the volume to 40 cm
. Then the flask was cooled, poured 100 cm
of water saturated with carbonic acid, and after standing for 3 min, the solution heated to boiling, reducing the amount of up to 60 cm
.
The solution was cooled for 3−5 min and filtered off from the precipitate, which was washed 6−8 times with water. The filtrate is titrated 0,1 n sulphuric acid solution in presence of 1−2 drops of methyl orange to yellow transition color of the solution pink.
4. PROCESSING OF THE RESULTS OF THE ANALYSIS
4.1. Mass fraction of sodium () in percent is calculated by the formula
where — amount of 0.1 n of sulfuric acid solution consumed for titration, cm
;
of 0.1 n sulfuric acid solution;
— hanging Babbitt,
4.2. Allowable absolute differences between the extreme results of the analysis should not exceed 0.02% when the mass fraction of sodium of 0.2 to 0.5%; 0,04% when the mass fraction of sodium more than 0.5 to 1.0%.
(Changed edition, Rev. N 1).
