ISO INTERNATIONAL STANDARD 28723 First edition 2008-10-15 Vitreousandporcelainenamels Determination of the edge covering on enamelled steel plate to be used in heat exchangers Emauxvitrifies- Déterminationdurevetement deI'aretesurune plaque en acierémaille destinee aux échangeurs de chaleur Reference number ISO 28723:2008(E) ISO @ISO2008 ISO28723:2008(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below COPYRIGHTPROTECTEDDOCUMENT ISO2008 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, ISO's member body in the country of the requester. ISO copyright office Casepostale56.CH-1211Geneva20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland ii ISo2008-Allrights reserved ISO28723:2008(E) Contents Page Foreword ..iv 1 Scope. 2 Normative references. .1 3 Principle... .1 4 Reagentsandmaterials... .1 5 Apparatus. 6 Testspecimens.. 7 Procedure. .4 8 Calculationandexpressionofresults .4 6 Precision.. 10 Test report. @ Is0 2008-All rights reserved ili ISO28723:2008(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies technical committees.Each memberbody interested in a subject for whichatechnical committee has been International Electrotechnical Commission (IEC)onall mattersofelectrotechnical standardization International Standards are drafted in accordance with the rules given in the ISO/lEC Directives, Part 2. adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval byat least75%of thememberbodies castingavote. rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO28723waspreparedbythe EuropeanCommitteeforStandardization(CEN)(as EN14863)andwas adopted,under a special“fast-track procedure",by Technical Committee ISO/TC 107,Metallic and other iv @ISO2008-Allrights reserved ISO 28723:2008(E) INTERNATIONALSTANDARD Vitreous andporcelain enamelsDeterminationofthe edge covering on enamelled steel plate to be used in heat exchangers 1 Scope This International Standard specifies a test method for the determination of the covering of the edge of enamelled steel platetobe used inheat exchangers.Thismethod is applicabletoall enamellingprocesses. It is applicabletoplates with a thickness between 0,5 mmand 1,5mm. This method is notapplicable where the current flowgenerated in thetest exceeds 3A. Normativereferences The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments)applies. Iso3696,Waterforanalytical laboratoryuse-Specificationandtestmethods EN10088-1,Stainlesssteels-Listofstainlesssteels 3 Principle at the edge. 4 Reagentsandmaterials During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and distlled or de-mineralized water or water of equivalent purity. 4.1 Pickling fluid, consisting of sulfuric acid (H2SO4) solution, (7±0,5)% by mass, with an Fe2+ concentration of (2 ± 1,5) g/l, at a temperature of (60 ± 2)°C. 4.2 Test bath electrolyte, consisting of sodium chloride solution, 5 % NaCl by mass, made with distilled water conforming tograde3of iSO 3696,ata temperatureof(22±3)C. ISO 2008 -All rights reserved 1 ISO28723:2008(E) 5 Apparatus 5.1 electrodes and