ANSI API MPMS 14.3.1-2012 Orifice Metering of Natural Gas and Other Related Hydrocarbon Fluids-Concentric Square-edged Orifice Meters Part 1 General Equations and Uncertainty Guide.pdf

1、Orifice Metering of Natural Gas and Other Related Hydrocarbon FluidsConcentric, Square-edged Orifice MetersPart 1: General Equations and Uncertainty GuidelinesAGA Report No. 3Part 1Manual of Petroleum Measurement StandardsChapter 14.3.1American Gas Association400 North Captiol Street, NWWashington,

2、DC 20001American Petroleum Institute1220 L Street, NWWashington, DC 20005FOURTH EDITION, SEPTEMBER 2012 ERRATA, JULY 2013REAFFIRMED, SEPTEMBER 2017An American National StandardANSI/API MPMS Ch. 14.3.1/AGA Report No. 3, Part 1Special NotesThis AGA/API publication necessarily addresses problems of a g

3、eneral nature. With respect to particularcircumstances, local, state, and federal laws and regulations should be reviewed.Neither AGA and API nor any of AGAs or APIs employees, subcontractors, consultants, committees, or otherassignees make any warranty or representation, either express or implied,

4、with respect to the accuracy,completeness, or usefulness of the information contained herein, or assume any liability or responsibility for any use,or the results of such use, of any information or process disclosed in this publication. Neither AGA and API nor any ofAGAs or APIs employees, subcontra

5、ctors, consultants, or other assignees represent that use of this publicationwould not infringe upon privately owned rights.This AGA/API publication may be used by anyone desiring to do so. Every effort has been made by AGA/API toassure the accuracy and reliability of the data contained in it; howev

6、er, AGA/API makes no representation, warranty,or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss ordamage resulting from its use or for the violation of any authorities having jurisdiction with which this publication mayconflict.T

7、his AGA/API publication is published to facilitate the broad availability of proven, sound engineering and operatingpractices. It is not intended to obviate the need for applying sound engineering judgment regarding when and wherethis publication should be utilized. The formulation and publication o

8、f this AGA/API publication is not intended in anyway to inhibit anyone from using any other practices.Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standardis solely responsible for complying with all the applicable requirements of that standa

9、rd. API does not represent,warrant, or guarantee that such products do in fact conform to the applicable API standard.All rights reserved. No part of this work may be reproduced, translated, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, o

10、r otherwise, without prior written permission from either the American Gas Association, 400 N. Capitol St., NW, Washington, DC 20001 or API Publishing Services, 1220 L Street, NW, Washington, DC 20005.Copyright 2012 American Gas Association and American Petroleum InstituteForewordNothing contained i

11、n this AGA/API publication is to be construed as granting any right, by implication or otherwise, forthe manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anythingcontained in the publication be construed as insuring anyone against liability for

12、 infringement of letters patent.This document was produced under API standardization procedures that ensure appropriate notification andparticipation in the developmental process and is designated as API Manual of Petroleum Measurement Standard(MPMS) Chapter 14.3.1 and AGA Report No. 3, Part 1. Ques

13、tions concerning the procedures under which thispublication was developed should be directed in writing to the Director of Standards, American Petroleum Institute,1220 L Street, NW, Washington, DC 20005. Questions concerning the interpretation of the content of this publicationshould be directed to

14、the Director of Standards, American Petroleum Institute, 1220 L Street, NW, Washington, DC20005 and to the Vice President, Operations and Engineering, American Gas Association, 400 N. Capitol Street, NW,Washington, DC 20001, and shall be handled in accordance with APIs Procedures for Standards Devel

15、opment.Requests for permission to reproduce or translate all or any part of the material published herein should also beaddressed to the Director of Standards, American Petroleum Institute (as above) or the Vice President, Operationsand Engineering, American Gas Association (as above).This AGA/API p

16、ublication is reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-timeextension of up to two years may be added to this review cycle. Status of the publication can be ascertained from theAPI Standards Department, telephone (202) 682-8000. A catalog of API publications and

17、 materials is publishedannually by API, 1220 L Street, NW, Washington, DC 20005.A catalog of AGA Operations and Engineering publications, which is published and updated as needed and canbe obtained by contacting AGA Operations and Engineering Department, phone (202) 824-7000 or web sitehttp:/www.aga

18、.org/Pages/contact_us.aspx. Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW,Washington, DC 20005, standardsapi.org or Operations and Engineering Department, American Gas Association,400 North Capitol Street, NW, Washington, DC 20001, http:/

19、www.aga.org/Pages/contact_us.aspx.iiiContentsPage1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 Organization of Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Normative References. . . . . . . . . . .

21、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Terms, Definitions, and Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 Terms and Definitions. .

22、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.2 Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23、 . . . 74 Field of Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.1 Applicable Fluids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

24、 . . . . . . . . . . . . . . . . . . . . 84.2 Types of Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.3 Uncertainty of Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Method of Calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 Orifice Flow Equation . . . . . . . . . . . . . . . . . . . . . . . .

26、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106.1 Velocity of Approach Factor (Ev) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.2 Orifice Plate Bore Diameter (d). . . . . . . . .

27、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.3 Meter Tube Internal Diameter (D). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Empirical Coefficient of Discharge

28、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137.1 Regression Database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147.2 Empirical Coeffici

29、ent of Discharge Equation for Flange-tapped Orifice Meters . . . . . . . . . . . . . . . . . . . . 157.3 Reynolds Number (ReD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167.4 Flow Conditions. . . . . . . . . .

30、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167.5 Pulsating Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 E

31、mpirical Expansion Factor (Y ) for Flange-tapped Orifice Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198.1 Upstream Expansion Factor (Y1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208.2 Downstream Ex

32、pansion Factor (Y2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 In-situ Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

33、29.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229.2 Meter Factor (MF). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

34、. . . . . . . . . . . . . . . . . . . . 2210 Fluid Physical Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2310.1 Viscosity () . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

35、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2310.2 Density (t,p, b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2310.3 Isentropic Exponent (). . . . . . . . . . . . . . .

36、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2411 Unit Conversion Factors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2411.1 Orifice Flow Equation . . . .

37、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2411.2 Reynolds Number Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2511.3 Expans

38、ion Factor Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2511.4 Flow Rate per Unit of Time Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251

39、2 Practical Uncertainty Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2812.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

40、. . . . . . . . . . . . . . 2812.2 Uncertainty Over a Flow Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2812.3 Uncertainty of Flow Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

41、 . . . . . . . . . . . . . . . . . . . . . . . 2812.4 Typical Uncertainties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3112.5 Example Uncertainty Calculations . . . . . . . . . . . . . . . . . . . . . . . .

42、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37vContentsPageAnnex A (informative) Discharge Coefficients for Flange-tapped Orifice Meters . . . . . . . . . . . . . . . . . . . . . . . 40Annex B (informative) Adjustments for Instrument Calibration and Use . . . . . . . . . . . .

43、 . . . . . . . . . . . . . . . . . . 51Annex C (informative) Buckingham and Bean Empirical Expansion Factor (Y) for Flange-tapped Orifice Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Bibliograph

44、y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Figures1 Orifice Tapping Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

45、. . . . . . . . . . . . . . . 52 Orifice Meter Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Contribution to Flow Error Due to Differential Pressure Instrumentation . . . . . . . . . . . . . . . . .

46、 . . . . . . . . 294 Empirical Coefficient of Discharge: Uncertainty at Infinite Reynolds Number . . . . . . . . . . . . . . . . . . . . . 325 Relative Change in Uncertainty: Dependence on Reynolds Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326 Practical Uncertainty Levels. . .

47、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Tables1 Linear Coefficient of Thermal Expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Orifice Flow Rate Equ

48、ation: Unit Conversion Factor (N1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Reynolds Number Equation: Unit Conversion Factor (N2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 Empirical Expansion Factor Equation: Unit Conversio

49、n Factor (N3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 Uncertainty Statement for Empirical Expansion Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336 Example Uncertainty Estimate for Liquid Flow Calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 387 Example Uncertainty Estimate for Natural Gas Flow Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39A.1 Discharge Coefficients for Flange-tapped Orifice Meters: Nominal 2-in. (50-mm) MeterD = 1.939 in. (49.25