ISO INTERNATIONAL STANDARD 2503 Third edition 2009-07-15 Gas welding equipment Pressure regulators and pressure regulators with flow-metering devices for gas cylinders used in welding, cutting and allied processes up to 300 bar (30 MPa) Materiel de soudage aux gazDetendeurs et detendeurs debitmetres integrés pour bouteilles de gaz utilisés pour le soudage, le coupage et les techniques connexes jusqu'a 300bar (30 MPa) Reference number ISO 2503:2009(E) @ ISO 2009 ISO 2503:2009(E) Contents Page Foreword .iv 1 Scope 2 Normative references 3 Terms and definitions 4 Symbols and abbreviated terms. 5 Design requirements 5.1 Materials. 5.2 Design and construction 6 Physical performance and operating characteristics. 6.1 6.2 Flow rates for pressure regulators without flow-metering devices 6.3 Equipment classes forpressure regulators without flow-metering devices 6.4 Pressure-relief valve...... 6.5 Operating-temperaturerange.. 6.6 Performance and operating characteristics .. 7 Marking.... 7.1 Pressure regulators without flow-metering devices. 7.2 Pressure regulators with flow-metering devices 11 8 Instructionsforuse. 12 9 Type-test procedure 12 9.1 General .... 12 9.2 Test samples and necessary documents .. 13 9.3 Test conditions..... 13 9.4 Units.... 13 9.5 metering devices ... ..14 9.6 Test for performance and operating characteristics of pressure regulator with flow- metering devices.. 9.7 Tests for mechanical resistance of pressure regulators or pressure regulator with a flow- meteringdevice. .19 9.8 Test for durability of markings. Annex A (informative) Pressure regulators 24 Annex B (informative) Operating principles of pressure regulators with flow-metering devices.. Bibliography..... ili ISO2503:2009(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 InternationalElectrotechnicalCommission(lEC)onallmattersofelectrotechnicalstandardization. International Standards are drafted in accordance with the rules given in the ISO/lEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an InternationalStandardrequiresapprovalbyatleast75%of thememberbodiescastingavote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO 2503 was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee Sc8,Equipmentforgas welding,cuttingand alliedprocesses. This third edition cancels and replaces the second edition (IsO 2503:1998), and also IS0 7292:1997, which havebeentechnicallyrevised Requests for official interpretations of any aspect of this International Standard should be directed to the found at www.iso.org IS0 2009-All rights reserved