GOST 1219.5-74
GOST 1219.5−74 calcium Babbits. Method for the determination of tin (with Change No. 1)
GOST 1219.5−74
Group B59
INTERSTATE STANDARD
CALCIUM BABBITS
Method for determination of tin content
Lead-calcium bearing alloys.
Method for determination of tin 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. VI
EDITION (September 2003) with amendment No. 1, approved in November 1979 (ICS 1−80).
This standard applies to calcium babbits and sets the volumetric iodometric method for the determination of tin (with tin content from 1.15 to 2.50%).
The method is based on the restoration of the tetravalent metal tin lead to the ferrous state and titration of recovered tin and iodine in the presence of potassium iodide and starch.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1219.0−74.
2. APPARATUS, REAGENTS AND SOLUTIONS
Funnel with water seal (see drawing).
Feed hopper with hydraulic gate
Nitric acid GOST 4461−77 diluted 1:1.
Sulfuric acid GOST 4204−77, diluted 1:1.
Hydrochloric acid by the GOST 3118−77.
The soluble starch according to GOST 10163−76, 1% freshly prepared solution.
Sodium bicarbonate according to GOST 4201−79, saturated solution.
Potassium iodide according to GOST 4232−74.
Iodine crystal according to GOST 4159−79, of 0.025 n solution; prepared as follows: 3.2 g of iodine dissolved in 50 cm40% solution of potassium iodide and dilute with water to 1 DM
or prepare fiksanala.
Potassium hydroxide.
Potassium ignominously according to GOST 4202−75, of 0.025 n solution; prepared as follows: 0.9 g odnomodovogo potassium, 10 g of potassium iodide and 20 g of potassium hydroxide dissolved in water and adjusted to 1 DM.
Tin GOST 860−75 stamps O1.
Lead according to GOST 3778−98 brand S00, plates with a total area of 60−70 cm, rolled in a spiral.
The titer determination of iodine solution and potassium odnomodovogo
Of 0.025 n solution of iodine, prepared as specified in sec. 2, is kept in a dark bottle 10−15 days, and then set its caption to a solution of tin. The solution of tin is prepared as follows: 0.5 g of tin are placed in a conical flask with a capacity of 250 cmand dissolved in 20−25 cm
of sulphuric acid when heated.
After dissolution and cooling the solution poured 100−120 cmof cold water and 50 cm
of hydrochloric acid. The solution was transferred to volumetric flask with a capacity of 500 cm
and after cooling, was adjusted to the mark with water.
To set caption select exactly 25 cmof a solution of tin, and placed in a conical flask with a capacity of 250 cm
, add 30 cm
of hydrochloric acid and bring the solution volume up to 140−150 cm
.
In the thus prepared flask immersed metallic lead in the form of spirals with a total area of 60−70 cm, cover the flask with a small funnel, heated to boiling and boiled for 20 min. For 1−2 min until the end of the recovery cover the flask with a rubber stopper inserted in her hopper with hydraulic gate. The funnel pre-poured saturated solution of sodium bicarbonate. Upon cooling above the solution in the flask is compressed gas, resulting in a saturated solution of sodium bicarbonate is sucked from the nozzle into the flask. As a result of interaction of sodium bicarbonate with hydrochloric acid produces carbon dioxide, the excess amount which can exit through the siphon.
At the end of the recovery flask and the solution cooled in running water to room temperature, adding as needed to funnel a solution of sodium bicarbonate. After cooling the solution, remove the funnel, into the flask, add a piece of marble about 5 g and add 0.2−0.3 g of potassium iodide, 3−5 cmstarch solution and titrated solution of iodine or potassium odnomodovogo. The titration performed in presence of lead, the remaining undissolved.
The titer of iodine solution (), expressed in g/cm
tin, calculated by the formula
where — hanging tin g;
— number of solution of iodine or potassium odnomodovogo consumed for titration of tin, cm
;
— the volume of the flask with standard solution of tin, cm
;
— the number of solution of tin, taken for titration, sm
.
(Changed edition, Rev. N 1).
3. ANALYSIS
A portion of the babbit 1 g is placed in a conical flask with a capacity of 250 cm, and dissolved in 20 cm
of nitric acid, diluted 1:1. After the decomposition of the alloy, and cooling the solution add 30 cm
of sulphuric acid diluted 1:1, and the solution evaporated until the appearance of dense white fumes of sulphuric anhydride. To the cooled sample carefully pour 10−15 cm
of cold water and again evaporated to the appearance of dense white fumes. Dilution and evaporation is repeated one more time. Then, after cooling the samples carefully poured 110−120 cm
of water and 25−30 cm
of hydrochloric acid. In thus prepared sample is immersed a plate of lead with a total area of 60−70 cm
, covered with a funnel and boil for 1 hour Then close a shutter of Haeckel and boil for 30 min, restore tetravalent tin and complete analyses, as specified in sec. 2 when the titer determination. At the same time through all stages of the analysis carried out control experience in the determination of tin in chemicals.
(Changed edition, Rev. N 1).
4. PROCESSING OF THE RESULTS OF THE ANALYSIS
4.1. Mass fraction of tin () in percent is calculated by the formula
where the titer of the iodine solution or potassium odnomodovogo, expressed in g/cm
tin;
— number of solution of iodine or potassium odnomodovogo consumed for titration of sample, cm
;
— number of solution of iodine or potassium odnomodovogo consumed for titration of the solution in the reference experiment, cm
;
— hanging Babbitt, g
.
4.2. The allowable divergence between the extreme results of the analysis shall not exceed 0.05 abs. %.
