1、AN AMERICAN NATIONAL STANDARDASME MFC-14M2003(Revision of ASME MFC-14M2001)MEASUREMENT 0FFLUID FLOW USINGSMALL BOREPRECISIONORIFICE METERSIntentionally left blank AN AMERICAN NATIONAL STANDARDMEASUREMENT OFFLUID FLOW USINGSMALL BOREPRECISIONORIFICE METERSASME MFC-14M2003(Revision of ASME MFC-14M2001
2、)Date of Issuance: April 17, 2003This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda issued to this edition.ASME will issue written replies to inquiries concerning interpretations of technical aspects of thisStandard. Interpretations are pub
3、lished on the ASME Web site under the Committee 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 NationalStandard
4、s. 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 for public review and comment that provides an opportunity for additiona
5、l public input 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 anyi
6、tems mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assume any such liability. Users of a code or standard are expresslyadvised that determination of the validity of any such patent righ
7、ts, 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 tho
8、se 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 pe
9、rmission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2003 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll Rights ReservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster . vCorrespondence With the MFC Committee . vi1 Scope an
10、d Field of Application 12 References and Related Documents 13 Symbols and Definitions 14 Principle of Measurement and Method of Computation 75 General Measurement Requirements . 96 Installation Requirements . 97 Discharge Coefficient and Empirical Equations 148 Uncertainties . 169 Pressure Loss, H90
11、04H9275 (h) 17Figures1 Standard Orifice Plate . 112 Corner Tap Geometry 133 Location for Orifice Flange Pressure Taps . 144 Honed Small Bore Orifice Flow Section With Corner Taps . 15Tables1 Symbols . 22 Minimum Recommended Upstream Straight Length Required to Achieve anUncertainty of 0.75% . 10iiiF
12、OREWORDBefore the publication of this Standard, there was no standard covering the measurementsof fluid flows using small bore precision orifice meters (nominal line sizes of14in. through 112in.) using differential pressure devices. Most people have used ASME fluid meters for guidanceor obtained inf
13、ormation from the manufacturers of proprietary devices.This Standard has been prepared by the ASME Committee on Measurement of Fluid Flows inClosed Conduit (MFC).Suggestions for improvement of this Standard should be sent to: Secretary, MFC, The AmericanSociety of Mechanical Engineers, Three Park Av
14、enue, New York, NY 10016.This Standard was approved as an American National Standard on February 26, 2003.ivASME MFC COMMITTEEMeasurement of Fluid Flow in Closed Conduits(The following is the Roster of the Committee at the time of approval of this Standard.)OFFICERSZ. D. Husain, ChairR. J. DeBoom, V
15、ice ChairR. L. Crane, SecretaryCOMMITTEE PERSONNELC. J. Blechinger, ConsultantR. W. Caron, Visteon Corp.G. P. Corpron, ConsultantR. L. Crane, The American Society of Mechanical EngineersR. J. DeBoom, Daniel Measurement and ControlP. G. Espina, Controlotron Corp.D. Faber, Badger Meter, Inc.R. H. Frit
16、z, Saudi AramcoF. D. Goodson, Daniel Measurement and ControlZ. D. Husain, Chevron TexacoE. H. Jones, Jr., Chevron Petroleum TechnologiesT. M. Kegel, Colorado Engineering Experiment Station, Inc.C. G. Langford, Cullen G. Langford, Inc.W. M. Mattar, Invensys / Foxboro Co.G. E. Mattingly, National Inst
17、itute of Standards and TechnologyD. R. Mesnard, Direct Measurement Corp.R. W. Miller, R. W. Miller and Associates, Inc.A. M. Quraishi, American Gas AssociationB. K. Rao, ConsultantW. F. Seidl, Colorado Engineering Experiment Station, Inc.D. W. Spitzer, Cooperhill and Pointer, Inc.D. H. Strobel, Cons
18、ultantJ. H. Vignos, ConsultantD. E. Wiklund, Rosemount, Inc.D. C. Wyatt, Wyatt Engineering and DesignSUBCOMMITTEE 23 SMALL BORE ORIFICE METERSZ. D. Husain, Chair, Chevron TexacoR. L. Crane, Secretary, The American Society of Mechanical EngineersG. P. Corpron, ConsultantG. E. Mattingly, National Inst
19、itute of Standards and TechnologyR. J. W. Peters, McCrometerD. E. Wiklund, Rosemount, Inc.D. C. Wyatt, Wyatt Engineering and DesignvCORRESPONDENCE WITH THE MFC COMMITTEEGeneral. ASME Standards are developed and maintained with the intent to representthe consensus of concerned interests. As such, use
20、rs of this Standard may interact with theCommittee by requesting interpretations, proposing revisions, and attending committeemeetings. Correspondence should be addressed to:Secretary, MFC Standards CommitteeThe American Society of Mechanical EngineersThree Park AvenueNew York, NY 10016-5990Proposin
21、g Revisions. Revisions are made periodically to the Standard to incorporatechanges that appear necessary or desirable, as demonstrated by the experience gained fromthe application of the Standard. Approved revisions will be published periodically.The Committee welcomes proposals for revisions to thi
22、s Standard. Such proposals shouldbe as specific as possible, citing the paragraph number(s), the proposed wording, and adetailed description of the reasons for the proposal, including any pertinent documentation.Interpretations. Upon request, the MFC Committee will render an interpretation ofany req
23、uirement of the Standard. Interpretations can only be rendered in response to awritten request sent to the Secretary of the MFC Standards Committee.The request for interpretation should be clear and unambiguous. It is further recom-mended that the inquirer submit his request in the following format:
24、Subject: Cite the applicable paragraph number(s) and the topic of the inquiry.Edition: Cite the applicable edition of the Standard for which the interpretationis being requested.Question: Phrase the question as a request for an interpretation of a specificrequirement suitable for genral understandin
25、g and use, not as a requestfor an approval of a proprietary design or situation. The inquirer mayalso include plans or drawings which are necessary to explain the ques-tion; however, they should not contain proprietary names or infor-mation.Requests that are not in this format will be rewritten in t
26、his format by the Committeeprior to being answered, which may inadvertently change the intent of the original request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation that might affect an interpretation is available. Further, persons aggrieved byan i
27、nterpretation may appeal to the cognizant ASME Committee or Subcommittee. ASMEdoes not “approve”, “certify”, “rate”,or“endorse” any item, construction, proprietarydevice, or activity.Attending Committee Meetings. The MFC Committee regularly holds meetings, whichare open to the public. Persons wishin
28、g to attend any meeting should contact the Secretaryof the MFC Standards Committee.viASME MFC-14M2003MEASUREMENT OF FLUID FLOW USINGSMALL BORE PRECISION ORIFICE METERS1 SCOPE AND FIELD OF APPLICATIONThis Standard specifies the geometry and method ofuse (installation and flowing conditions) for orifi
29、cemeters of 6 mm to 40 mm (14in. to 112in.) line sizewhen they are inserted in a conduit running full. It alsogives necessary information for calculating flow rateand its associated uncertainty.It applies only to differential pressure devices in whichthe flow remains subsonic throughout the measurin
30、gsection, flow is steady or varies only slowly with time,and the fluid is considered single-phase. In addition,the uncertainties are given in the appropriate sectionsof this Standard for each of these devices within the pipesize and Reynolds number limits, which are specified.This Standard covers de
31、vices for which sufficient cali-brations have been made to enable the specification ofcoherent systems of application and to enable calcula-tions to be made with certain predictable limits of uncer-tainty.The devices introduced into the pipe are called pri-mary devices. The term primary device also
32、includes thepressure taps and the associated upstream and down-stream piping. All other instruments or devices requiredfor the measurement or transmission of the differentialpressures are known as secondary elements, and in com-bination are referred to as the secondary devices. ThisStandard covers t
33、he primary devices; the secondarydevices will be mentioned only occasionally, as andwhen necessary for the proper operation of the primarydevice.The different primary devices covered in this Stan-dard are(a) orifice plates used with corner pressure taps;(b) orifice plates used with flange pressure t
34、aps;(c) specially designed orifice meters with integral fit-tings.2 REFERENCES AND RELATED DOCUMENTSASME MFC-1M Glossary of Terms Used in the Measure-ment of Fluid Flow in PipesASME MFC-2M Measurement Uncertainty for FluidFlow in Closed ConduitsASME MFC-8M Fluid Flow in Closed Conduits Con-nections
35、for Pressure Signal Transmissions BetweenPrimary and Secondary Devices1Filban, T.J. 1961. The Orifice Flow Section for MeteringLow Rates of Flow. Instruments and Control Systems(February).Filban, T.J. 1958. Orifice Metering of Small Volumes inMeter Tubes of12in.,34in., and 1 in. Sizes. Paperpresente
36、d at the ASME Application Gas MeasurementShort Course.Filban, T.J., and W.A. Griffin. 1959. Small-Diameter-Ori-fice Metering. Transactions of the ASME Journal ofBasic Engineering. Paper No. 59-A-101.Fluid Meters, Their Theory and Application. 1971. 6th ed.Publisher: American Society of Mechanical En
37、gineers(ASME International), Three Park Avenue, New York,NY 10016; Order Department: 22 Law Drive, Box 2300,Fairfield, NJ 07007ISO 2186 Fluid Flow in Closed Conduits Connectionsfor Pressure Signal Transmissions Between Primaryand Secondary DevicesISO 4006 Measurement of Fluid Flow in Closed Con-duit
38、s Vocabulary and SymbolsISO 4185 Measurement of Liquid Flow in Closed Con-duits Weighing MethodISO 5168 Measurement of Fluid Flow Evaluation ofUncertaintiesISO/DIS 8316 Measurement of Liquid Flow in ClosedConduits Method by Collection of the Liquid in aVolumetric TankPublisher: International Organiz
39、ation for Standardiza-tion (ISO), 1 rue de Varembe, Case Postale 56, CH-1211, Geneve, Switzerland/Suisse3 SYMBOLS AND DEFINITIONSThe vocabulary and symbols used in this Standardare defined in ASME MFC-1M and ISO 4006. The SI andcustomary (U.S.) measurement units are used through-out, with the SI uni
40、ts listed first and the customary unitsfollowing in parentheses, whenever stated.3.1 SymbolsTable 1 reproduces the symbols and their respectiveSI and customary dimensional units that are used in thisStandard.ASME MFC-14M2003 MEASUREMENT OF FLUID FLOW USING SMALL BORE PRECISIONORIFICE METERSTable 1 S
41、ymbolsDimensionsM: MassL: Length U.S. UnitT: Time Note (1)Symbols Represented Quantity H9258: Temperature SI Unit CustomaryC Discharge coefficient dimensionless . . . . . .CpSpecific heat at constant L2T2H92581J/(kg mole K) BTU/(lbm mole R)pressureCvSpecific heat at constant L2T2H92581J/(kg mole K)
42、BTU/(lbm mole R)volumec Speed of sound LT1m/s ft/sD Upstream internal pipe diameter L m in.at flowing conditionsd Diameter of orifice of primary L m in.device at flowing conditionsdmeasDiameter at a specified L m in.measured temperatureE Orifice plate thickness L m in.erRelative uncertainty dimensio
43、nless . . . . . .FaThermal expansion correction dimensionless . . . . . .factorGiIdeal specific gravity (gas), MW dimensionless . . . . . .of gas/MW of airMW of gas p Molecular weight M kg/mole lbm/moleof the gasMW of air p Molecular weight of M kg/mole lbm/moleair p 28.96247G Relative density (liqu
44、ids), dimensionless . . . . . .Specific GravitygcConversion constant dimensionless kg m/(N s2) 32.17405 lbm ft/(lbfs2)goStandard acceleration due to LT2m/s2ft/s2gravity, 9.806650 m/s232.17405 ft/s2h Pressure loss see H9004H9275 (h) . .hwDifferential pressure see H9004H9267 (hw) . .k (H9280) Uniform
45、equivalent roughness L m in.L Ratio of pressure tap spacing to dimensionless . . . . . .D, L p H5129/DH5129 Pressure tap spacing from L m in.orifice platen Polytropic exponent dimensionless . . . . . .p Static pressure of the fluid ML1T2Pa lbf/in.22MEASUREMENT OF FLUID FLOW USING SMALL BORE PRECISIO
46、N ASME MFC-14M2003ORIFICE METERSTable 1 Symbols (Contd)DimensionsM: MassL: Length U.S. UnitT: Time Note (1)Symbols Represented Quantity H9258: Temperature SI Unit CustomarypcAbsolute critical pressure of a substance ML1T2Pa lbf/in.2pnStatic pressure of flowing fluid at ML1T2Pa lbf/in.2upstream press
47、ure tappf2Static pressure of flowing fluid at ML1T2Pa lbf/in.2downstream tapqmMass rate of flow, MT1kg/s lbm/sqmp H9267fqH9263p H9267bqH9263bqH9263Volume rate of flow at flowing conditions L3T1m3/s ft3/sqH9263bVolume rate of flow at base conditions, L3T1m3/s ft3/sqH9263bp qH9263H9267fH9267bR Radius
48、L m in.RaArithmetical mean deviation from the L m in.mean line of the profile (for furtherdetails refer to ISO/R-468)RD, RdReynolds number referred to D or d dimensionless . . . . . .T Absolute temperature of the flowing fluid H9258 K Rt Temperature of the flowing fluid H9258 C FtmeasTemperature at
49、which dimension of the H9258 C Fpipe and plates are measuredtrReference Temperature H9258 C FU Mean axial velocity of the fluid in the pipe LT1m/s ft/sY Expansion factor see H9280 (Y) . .Z Gas (vapor) compressibility factor dimensionless . . . . . .H9251PThermal expansion factor of the pipe H92581(m/m)/C (in./in.)/FH9251PEThermal expansion factor of the primary H92581(m/m)/C (in./in.)/FelementH9252 Diameter ratio, H9252 p d/D, at flowing dimensionless . . . . . .conditionsH9004p (hw) Different
