OSI 671 International Standard INTE RNATIONAL ORGANIZATION FOR STANDARDIZATION MEXAYHAPOAHAA OPTAHW3AUMA nO CTAHAAPTM3AUMMORGANISATION INTE RNATIONALE DE NORMALISATION Steel and cast iron -- Determination of sulphur content Combustion titrimetric method Aciers et fontes -- Dosage du soufre -- Methode titrimetrique apres combustion First edition - 1982-11-15 UDC 669.13/.14 : 543.24 : 546.22 Ref. No. 1SO 671-1982 (E) ISO 671-1982 (E) Descriptors : steels, cast iron, chemical analysis, determination of content, suiphur, combustion analysis, volumetric analysis. Price based on 5 pages Copyright International Organization for Standardization Not for Resal Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards institutes (iso member bodies). The work of developing Inter- national Standards is carried out through Iso technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. International Standard ISO 671 was developed by Technical Committee ISO/TC 17, Steel. it was submitted directly to the iSo Council, in accordance with clause 5.10.1 of part 1 of the Directives for the technical work of ISo. It cancels and replaces IsO Recommendation R 671-1968, which had been approved by the member bodies of the following countries : Hungary Australia Romania Austria India South Africa, Rep. of Belgium Israel Spain Brazil Italy Sweden Canada Japan Switzerland Chile Korea, Rep. of Turkey Czechoslovakia Netherlands United Kingdom Denmark New Zealand Yugoslavia Norway Egypt, Arab Rep. of Poland Germany, F. R. The member bodies of the following countries had expressed disapproval of the docu- ment on technical grounds : France Portugal USA International Organization for Standardization, 1982 ? Printed in Switzerland Copyright International Organization for Standardization Not for Resa ISO 671-1982 (E) INTERNATIONAL STANDARD Steel and cast iron -- Determination of sulphur content - Combustion titrimetric method 1 Scope and field of application 4.1 Oxygen, minimum purity 99 % (V/V, free from sulphur-bearing compounds. This International Standard specifies a titrimetric method for the determination of sulphur in steel and cast iron, after com- 4.2 Soda asbestos, particle size : approximately 2 mm. bustion of the test portion in a current of oxygen. 4.3 Magnesium perchlorate, Mg(ClO4/2, particle size : ap- proximately 2 mm. 2 References 4.4 Pure iron, of known low sulphur content. ISO 377/2, Selection and preparation of samples and test pieces of wrought steels Part 2 : Samples and test pieces in. 4.5 Fluxes, iron, copper or tin, of known low sulphur con- tended for the determination of the chemical composition.1) tent. . Woven metal wire cloth, perforated ISO 565,Test sieves plate and electroformed sheet - Nominal sizes of openings.2) Absorbent solution 4.6 cooled water. Add 100 mt of hydrogen peroxide and dilute to Principle 3 2 500 ml with boited and cooled water. Combustion of a test portion at a high temperature (1 450 oC) in a current of pure oxygen, if necessary in the presence of a 4.7 Sodium borate, standard solution, corresponding to metal flux. Transformation of sulphur into suiphur dioxide. Ab- 0,010 % of sulphur for 1 g/ml of test portion. sorption of the gases resuiting from combustion, freed from oxide dust, by a solution of potassium sulphate and hydrogen Weigh, to the nearest 0,000 1 g, 2,383 9 g of sodium borate peroxide. Na2B407.10H20, dissolve in boiled and cooled water and dilute to exactly 2 000 ml with the same water. Titration of the absorbent solution with a standard sodium