ISO INTERNATIONAL STANDARD 7624 First edition 1997-09-15 Petroleum products and lubricants - Inhibited mineral turbine oils - Determination of oxidation stability Produits pétroliers et lubrifiants - Huiles minerales inhibees pour turbines - Détermination de la stabilite a I'oxydation ISo Reference number ISO 7624:1997(E) No reproduction or networking permitted without license from IHS Not for Resale ISO7624:1997(E) Foreword IsoO (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO member bodies). The work of preparing International Standards is normally carried out through isoO technical committees. Each member body interested in a subject for which a technical committee has been established 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. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft international Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard IsO 7624 was prepared by Technical Committee ISO/TC 28, Petroleum products and lubricants. Annexes A, B and C form an integral part of this International Standard. @ISO1997 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utlized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56 : CH-1211 Geneve 20 . Switzerland Internet [email protected] X.400 C=ch; a=400net; p=iso; 0=isocs; S=central Printed in Switzerland ii se with ISC Not for Resale INTERNATIONAL STANDARD ISO ISO 7624:1997(E) Petroleum products and lubricants -- Inhibited mineral turbine oils - Determination of oxidation stability WARNING The use of this International Standard may involve hazardous material, operations and equipment. This International Standard does not purport to address all of the safety problems associated and health practices and determine the applicability of regulatory limitations prior to use. Scope This International Standard specifies a method for the determination of the resistance to oxidation under specified conditions of unused inhibited mineral turbine oils. The method is also applicable to other types of oil, such as hydraulic oil. NOTE This method may be used for specification purposes, and is of value in estimating the oxidation stability of turbine lubricants in the laboratory. It should be recognized, however, that correlation between the results of any single method of test for oxidation stability and thestability of an oil in servicewill vary with service conditions. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC.and Iso maintain registers of currently valid International Standards. ISO 3696:1987, Water for analytical laboratory use - Specification and test methods. IsO 4793:1980, Laboratory sintered (fritted) filters -- Porosity grading, classification and designation. 3 Principle Oxygen is passed for 164 h through a sample of the oil with added soluble metal catalysts (iron and copper) and (induction period), an acidity/time curve is obtained by daily determinations of the volatile acids. 4 Reagents and materials During the analyses, use only reagents of recognized analytical grade and water meeting the requirements of IsO 3696 Grade 2 or water of equivalent p