ISO INTERNATIONAL STANDARD 3545-3 First edition 1989-12-01 Steel tubes and fittings - Symbols for use in specifications - Part 3: Tubular fittings with circular cross-section Tubes et raccords en acier - Symboles a utiliser dans les specifications Partie 3:Accessoires tubulaires a section circulaire Reference number ISO3545-3:1989(E) No reproduction or networking permitted without license from IHS Not for Resale ISO3545-3:1989(E) Foreword ISo (the International Organization for Standardization) is a woridwide 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, govern- mental 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 approval before their acceptance as International Standards by the iso Council. They are approved in accordance with iSO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 3545-3 was prepared by Technical Committee ISO/TC 5 Ferrous metal pipes and metallic fittings. ISo 3545 consists of the following parts, under the general title Steel tubes and fittings - Symbols foruse in specifications: Part1:Tubes andtubularaccessorieswithcircularcross-section Part 2: Square and rectangular hollow sections Part3:Tubularfittingswithcircularcross-section AnnexAofthispartofIsO3545isforinformationonly. @ISO1989 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,withoutpermission in writing from the publisher. International Organization for Standardization Case postale 56 . CH-1211 Geneve 20Switzerland Printed in Switzerland No reproduction or networking permited without license from IHS Nt fr Resale 1SO 3545-3 : 1989 (E) INTERNATIONALSTANDARD Steel tubes and fittings - Symbols for use in specifications Part 3 : Tubular fittings with circular cross-section 1Scope T= thickness This part of ISo 3545 defines the most common symbols with F = value of bending radius the aim of standardizing and facilitating the use of terminology in standards for tubular fittings and associated products. L - length of straight end B = dimension from the back to the face or to the start of the 2 Fundamental symbols straight end for 180° bends D = specified outside diameter 5.2 Reducers (see figure 3) P= pressure D = major outside diameter T = specified thickness d = major inside diameter M.=unit mass T = thickness adjacent to major diameter 3Symbols for service conditions D, = minor outside diameter DN = nominal size d, = minor inside diameter PN = nominal pressure T, = thickness adjacent to minor diameter L = overall length of reducer PS = service pressure TS = service temperature 5.3 Tees (see figure 4) D = major outside diameter 4 Symbols for tolerances (see figure 1) d = major inside diameter See Iso 5252 : 1977, Steel tubes - Tolerance systems. T = thickness adjacent to major diameter Q = angular alignment D, minor outside diameter P = perpendicular alignment d, = minor inside diameter U = alignment of faces T, = thickness adjacent to minor diameter 5 Symbols for dimensions F = dimension from centreline to face at d for equal and reduc- ing tees 5.1 Bends (see figure 2) H = dimension from centreline to face at d, for reducing tees NOTE - Bends are usually designated by their curving diameter nD (e.g.3D,5D). 5.4 Caps (see figure 5) The numerical value of the curving (or bending) radius is designated by the letter F. D = outside diameter D