19-5_Edtn_2004.pdf

AN AMERICAN NATIO NAL STANDARDFlow MeasurementASME PTC 19.5-2004Performance Test CodesCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.ASME PTC 19.5-2004FlowMeasurementPerformance Test CodesAN AMERICAN NATIONAL STANDARDThree Park Avenue New York,NY 10016Copyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.Date of Issuance:July 25,2005The 2004 edition of ASME PTC 19.5 is being issued with an automatic addenda subscription service.The use of addenda allows revisions made in response to public review comments or committeeactions to be published as necessary.This Supplement will be revised when the Society approvesthe issuance of a new edition.ASME issues written replies to inquiries as code cases and interpretations of technical aspects ofthis document.Code cases and interpretations are published on the ASME Web site under theCommittee Pages at http:/www.asme.org/codes/as they are issued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards.The Standards Committee that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate.The proposed code or standard was madeavailable forpublic review andcomment thatprovides an opportunityfor additional publicinput from industry,academia,regulatory agencies,and the public-at-large.ASME does not“approve,”“rate,”or“endorse”any item,construction,proprietary device,or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with anyitems mentioned in this document,and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent,nor assumes any such liability.Users of a code or standard are expresslyadvised that determination of the validity of any such patent rights,and the risk of infringement of such rights,isentirely their own responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the establishedASME procedures and policies,which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue,New York,NY 10016-5990Copyright 2005 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.CONTENTSNotice.ixForeword.xCommittee Roster.xiCorrespondence With the PTC 19.5 Committee.xiiiSection 1Object and Scope.11-1Object.11-2Scope.1Section 2Definitions,Values,and Descriptions of Terms.22-1Primary Definitions and Systems of Units.22-2Historical Definitions of Units of Measurement.22-3Symbols and Dimensions.32-4Thermal Expansion.42-5Sources of Fluid and Material Data.4Section 3Differential Pressure Class Meters.193-0Nomenclature.193-1General Equation for Mass Flow Rate Through a DifferentialPressure Class Meter.193-2Basic Physical Concepts Used in the Derivation of the GeneralEquation for Mass Flow.203-3Theoretical Flow Rate Liquid As the Flowing Fluid.203-4Theoretical Flow Rate Gas or Vapor As the Flowing Fluid.213-5Errors Introduced in Theoretical Mass Flow Rate by IdealizedFlow Assumptions.213-6Discharge Coefficient C in the Incompressible Fluid Equation.213-7Discharge Coefficient C and the Expansion Factor?for Gases.213-8Calculation of Expansion Factor?.223-9Determining Coefficient of Discharge for Differential PressureClass Meters.223-10Thermal Expansion/Contraction of Pipe and Primary Element.233-11Selection and Recommended Use of Differential PressureClass Meters.233-12Restrictions of Use.243-13Procedure for Sizing a Differential Pressure Class Meter.243-14Flow Calculation Procedure.243-15Sample Calculation.253-16Sources of Fluid and Material Data.27Section 4Orifice Meters.284-0Nomenclature.284-1Introduction.284-2Types of Thin-Plate,Square-Edged Orifices.284-3Code Compliance Requirements.284-4Multiple Sets of Differential Pressure Taps.284-5Machining Tolerances,Dimensions,and Markings for Orifice Plate.284-6Machining Tolerances and Dimensions for Di