ISO INTERNATIONAL STANDARD 7440-2 Secondedition 1991-12-01 Road vehicles -Fuel injection equipment testing - Part 2: Orifice plate flow-measurement Vehicules routiers-Essaides équipements d'injection de combustible Partie2:Mesuragedudebit despastllesatrou eferencenumber 3O 7440-2:1991(E) ISO7440-2:1991(E) Foreword Iso(the International OrganizationforStandardization)is aworldwide federation of national standardsbodies (isomemberbodies).Thework ofpreparingInternationalStandards is normallycarriedoutthroughIso technical committees.Each member bodyinterested in a subject for whichatechnical committeehasbeen establishedhasthe righttobe represented on that committee.international organizations,govern- mental and non-governmental,in liaisonwithisO,also takepart inthe work.Iso collaborates closely with the International Electrotechnical Commission (IEC)on all matters of electrotechnical standardization. Draft International Standards adopted bythe technical committees are circulated to the member bodies for voting.Publication as an Inter- bodies casting a vote. InternationalStandardiso7440-2waspreparedbyTechnicalCommittee iso/Tc22,Road-vehicles,Sub-Committeesc7,Injectionequipmentand fitersforuseonroadvehicles. This second edition cancels and replaces the first edition (iso 7440-2:1985),ofwhichitconstitutesacompleterevision. iso7440consistsofthefollowingparts,underthegeneraltitleRoad vehicles -Fuel injection equipment testing: -Part1:Calibratingnozzleandholderassemblies Part2:Orificeplateflow-measurement AnnexesAandBofthispartofIsO7440areforinformationonly. ?ISO1991 All rights reserved,Nopart of thispubllcationmaybereproduced or utllized in anyform orby any means,electronic or mechanical, including photocopying and mlcrofilm,without permission in writing from the publisher. International Organization forStandardization Case Postale56CH-1211Geneve20·Switzerland Printed in-Switzerland ii ISO 7440-2:1991(E) INTERNATIONALSTANDARD Road vehicles -- Fuel injection equipment testing Part 2: Orifice plate flow-measurement Scope 3 Orificeplateflow-measuringsystem Thispart of iso7440 specifies the flow-measuring system,includingthefixture,tobeusedforflow testing the single hole orifice plates used in an orificeplatetypenozzleandholderassembly(de- 3.1 General description scribed in Iso 7440-1)which are intended fortesting and setting diesel fuel injection pumps on test Figure1 shows an orifice plate flow-measuring sys- benches. tem comprising: The flow-measuring system and fixture described in a) fluid supply circuit and flow-measuring device this part ofIso7440 ensureaccurateflow-testingof (an exampleis shown inannex A); the entire range oforifices from0,4mm to o,8mm diameter as specified in IsO 7440-1.It is intended primarilyfor use by the manufacturers of single hole b) orifice plate holding fixture; orificeplates. c) flow overcheck device (optional) [This device is forperiodic overchecking ofthe accuracy of the primary flow-measuring device in a) and is specified in annex B.J Thesystemshallbedesignedandconstructedwith particular attention being giventotheproblems as- 2 Normativereferences sociated with fluid evaporation,contamination,aer- ation and instability of pressure and temperature. The following standards contain provisions which, through reference in this text, constitute provisions Flow values obtained by allernative systems shall of thispart of iso7440.At the timeof publication, require correlationwith-values determinedusingthe the editions indicated were valid.All standards are system shown in figure1. subjectto revision, and parties toagreements based onthis part of Iso 7440 are encouraged to investi- gate the possibilityof applying the most recent edi- tions of the standards indicated below.Members of IEC and Iso maintain registers of currently valid In- 3.2Orificeplateholdingfixture ternational Standards. Iso4113:1988,Roadvehicles-Calibrationfluidfor The functionally critical details and dimensions of diesel injection equipment.