ISO INTERNATIONAL STANDARD 3174 Second edition 1994-12-01 Aircraft - Connections for checking hydraulic systems by ground appliances - Threaded type Aeronefs -- Raccords pour la verification des circuits hydrauliques par des appareils ausolTypefilete TSO Reference number ISO 3174 1994(E) No reproduction or networking permited without license from IHS Not for Resale ISO3174:1994(E) Foreword Iso (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 IsO 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. circulated to the member bodies for voting. Publication as an International a vote. International Standard ISO 3174 was prepared by Technical Committee IsO/TC 20,Aircraft and space vehicles,Subcommittee SC 10,Aerospace fluid systems and components. This second edition cancels and replaces the first edition (IS0 3174:1981), of which it constitutes a technical revision. Annex A of this International Standard is for information only. ?ISO1994 All rights reserved Unless otherwise specified, no part of this publication may be reproduced or utilized 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 CasePostale56.CH-1211Geneve20·Switzerland Printed in Switzerland orStandardizatior No reproduction or networking permitted without license from IHS Not for Resale ISO3174:1994(E) INTERNATIONAL STANDARD ISO Aircraft - Connections for checking hydraulic systems by ground appliances ---- Threaded type 1 Scope 4 Connecting thread This International Standard specifies the requirements for connections installed in aircraft hydraulic system pressure and suction lines, intended for checking the systems by means of ground appliances. 4.1 The profile, basic elements and dimensions of the three-start thread shall be in accordance with fig- 2 Normative references ure 2 and table 1. The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid. All standards are subject to revision, and parties to agreements 4.2 The end of the thread shall be relieved in order based on this International Standard are encouraged to ensure ease of engagement. to investigate the possibility of applying the most re- cent editions of the standards indicated below. Members of IEC and ISO maintain registers of cur- rently valid International Standards. 4.3 The thread shall be easily coupled or uncoupled ISo3323:1987,Aircraft—Hydraulic components from any position of engagement. Marking to indicate fluid for which component is ap- proved. MIL-STD-810, Environmental Test Methods and En- gineering Guidelines. 3 Basic connection elements 5 Installation of the connection The basic elements and dimensions of the con- nections shall be in accordance with figure 1 and Theclearanceenveiopefortheconnectionontheair- table 1. craft shall be in accordance with figure 3. No reproduction or networking permitted without license from IHS Not for Resale