1、Manual of Petroleum Measurement Standards Chapter 4Proving SystemsSection 2Displacement ProversTHIRD EDITION, SEPTEMBER 2003REAFFIRMED, MARCH 2011ADDENDUM, FEBRUARY 2015Manual of Petroleum Measurement Standards Chapter 4Proving SystemsSection 2Displacement ProversMeasurement CoordinationTHIRD EDITIO
2、N, SEPTEMBER 2003REAFFIRMED, MARCH 2011ADDENDUM, FEBRUARY 2015SPECIAL NOTESAPI publications necessarily address problems of a general nature. With respect to partic-ular circumstances, local, state, and federal laws and regulations should be reviewed.API is not undertaking to meet the duties of empl
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5、cture, sale, or use of any method, apparatus, or prod-uct covered by letters patent. Neither should anything contained in the publication be con-strued as insuring anyone against liability for infringement of letters patent.Generally, API standards are reviewed and revised, reaffirmed, or withdrawn
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8、12-5776. This document was produced under API standardization procedures that ensure appropri-ate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this standard or com-ments and questions conce
9、rning the procedures under which this standard was developed should be directed in writing to the Director of the Standards department, American Petro-leum Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to reproduce or translate all or any part of the material publis
10、hed herein should be addressed to the Director, Business Services.API standards are published to facilitate the broad availability of proven, sound engineer-ing and operating practices. These standards are not intended to obviate the need for apply-ing sound engineering judgment regarding when and w
11、here these standards should be utilized. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices.Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible
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13、ans, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission from the publisher. Contact the Publisher, API Publishing Services, 1220 L Street, N.W., Washington, D.C. 20005.Copyright 2003 American Petroleum InstituteFOREWORDChapter 4 of the Manual of Petroleum
14、 Measurement Standards was prepared as a guide for the design, installation, calibration, and operation of meter proving systems used by the majority of petroleum operators. The devices and practices covered in this chapter may not be applicable to all liquid hydrocarbons under all operating conditi
15、ons. Other types of prov-ing devices that are not covered in this chapter may be appropriate for use if agreed upon by the parties involved.The information contained in this edition of Chapter 4 supersedes the information con-tained in the previous edition (First Edition, May 1978), which is no long
16、er in print. It also supersedes the information on proving systems contained in API Standard 1101 Measure-ment of Petroleum Liquid Hydrocarbons by Positive Displacement Meter (First Edition, 1960); API Standard 2531 Mechanical Displacement Meter Provers; API Standard 2533 Metering Viscous Hydrocarbo
17、ns; and API Standard 2534 Measurement of Liquid Hydrocar-bons by Turbine-meter Systems, which are no longer in print.This publication is primarily intended for use in the United States and is related to the standards, specifications, and procedures of the National Institute of Standards and Technol-
18、ogy (NIST). When the information provided herein is used in other countries, the specifica-tions and procedures of the appropriate national standards organizations may apply. Where appropriate, other test codes and procedures for checking pressure and electrical equipment may be used.For the purpose
19、s of business transactions, limits on error or measurement tolerance are usually set by law, regulation, or mutual agreement between contracting parties. This publi-cation is not intended to set tolerances for such purposes; it is intended only to describe methods by which acceptable approaches to a
20、ny desired accuracy can be achieved. Chapter 4 now contains the following sections:Section 1, “Introduction”Section 2, “Displacement Provers”Section 4, “Tank Provers”Section 5, “Master-meter Provers”Section 6, “Pulse Interpolation”Section 7, “Field-standard Test Measures”Section 8, “Operation of Pro
21、ving Systems”Section 9, “Calibration of Provers”API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connec
22、tion with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any federal, state, or municipal regulation with which this publication may conflict.Suggested revisions are invited and should be submitted to
23、API, Standards department, 1220 L Street, NW, Washington, DC 20005.iiiCONTENTSPage1 INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24、. . . . . . . . . . . . . . . . . .11.2 Displacement Prover Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11.3 Definition of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11.4 Referenced Publications
25、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 GENERAL PERFORMANCE CONSIDERATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . .22.1 Repeatability and Accuracy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22.2
26、Base Prover Volume. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22.3 Valve Seating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22.4 Flow Stability. . . . . . . . . . . . . . . . . . . .
27、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22.5 Freedom from Hydraulic Shock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22.6 Temperature Stability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
28、2.7 Pressure Drop Across the Prover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32.8 Meter Pulse Train. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32.9 Detectors . . . . . . . . . . . . . . . . . . . . . . . . .
29、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 GENERAL EQUIPMENT CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.1 Materials and Fabrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.2 Internal and Extern
30、al Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.3 Temperature Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33.4 Pressure Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31、. . . . . . . . . . . .33.5 Displacing Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43.6 Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53.7 Connections . . . .
32、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53.8 Detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53.9 Peripheral Equipment . . . . . . . . . . . . . . . . . . . . . . .
33、 . . . . . . . . . . . . . . . . . . . . . . . .63.10 Unidirectional Sphere Provers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63.11 Unidirectional Piston Provers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83.12 Bidirectional
34、 Sphere Provers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93.13 Bidirectional Piston Provers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94 DESIGN OF DISPLACEMENT PROVERS . . . . . . . . . . . . . . . . . . . . . . . . .
35、. . . . . . . .114.1 Initial Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114.2 Design Accuracy Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124.3 Dimensions of a Displacement Prover . . . . . .
36、. . . . . . . . . . . . . . . . . . . . . . . . . . .135 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185.1 General Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185.2
37、 Prover Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19APPENDIX A ANALYSIS OF SPHERE POSITION REPEATABILITY . . . . . . . . . . .21APPENDIX B EXAMPLES OF PROVER SIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27APPENDIX
38、 C A PROCEDURE FOR CALCULATING MEASUREMENT SYSTEM UNCERTAINTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35APPENDIX D TYPICAL DISPLACEMENT PROVER DESIGN CHECK LIST . . . . .39APPENDIX E EVALUATION OF METER PULSE VARIATIONS . . . . . . . . . . . . . . .45APPENDIX F PROVER S
39、PHERE SIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47vPageFigures1 Typical Unidirectional Return-type Prover System . . . . . . . . . . . . . . . . . . . . . . . . . .72 Piston Type Prover with Shaft and Optical Switches. . . . . . . . . . . . . . . . . . . . . . . . .
40、83 Typical Bidirectional U-type Sphere Prover System . . . . . . . . . . . . . . . . . . . . . . . 104 Typical Bidirectional Straight-type Piston Prover System. . . . . . . . . . . . . . . . . . . .115 Pulse Train Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41、. . . . . . . . . . 13A-1 Diagram Showing the Relationship Between Sphere Position Repeatability and Mechanical Detector Actuation Repeatability. . . . . . . . . . . . . . . . . . . . . . . . . .21A-2 Sphere versus Detector Relationship at Various Insertion Depths for a 12 in. Prover with a 0.75 in.
42、 Diameter Detector Ball . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25A-3 Prover Length versus Detector Repeatability at Various Insertion Depths for a 12 in. Unidirectional Prover with a 0.75 in. Diameter Detector Ball. . . . . . . . . . . .25TablesC-1 Range to Standard Deviation Conve
43、rsion Factors . . . . . . . . . . . . . . . . . . . . . . . . . 35C-2 Student t Distribution Factors for Individual Measurements . . . . . . . . . . . . . . . . . 36C-3 Estimated Measurement Uncertainty of the System at the 95% Confidence Level for Data that Agree within a Range of 0.05% . . . . . .
44、 . . . . . . . . . . . . . . . . . 361Chapter 4Proving SystemsSection 2Displacement Provers1 IntroductionThis document, including figures, graphs and appendices addresses displacement provers. It includes provers that were commonly referred to as either “conventional” pipe provers or “small volume”
45、provers. “Conventional” pipe provers were those with sufficient volume to accumulate a minimum of 10,000 whole meter pulses between detector switches for each pass of the displacer. “Small volume” provers were those with insufficient volume to accumulate a minimum of 10,000 whole meter pulses betwee
46、n detector switches for each pass of the displacer.Displacement provers may be straight or folded in the form of a loop. Both mobile and stationary provers may be con-structed in accordance with the principles described in this chapter. Displacement provers are also used for pipelines in which a cal
47、ibrated portion of the pipeline (straight, U-shaped, or folded) serves as the reference volume. Some provers are arranged so that liquid can be displaced in either direction.When using a displacement prover the flow of liquid is not interrupted during proving. This uninterrupted flow permits the met
48、er to be proved under specific operating conditions and at a uniform rate of flow without having to start and stop.The reference volume (the volume between detectors) required of a displacement prover depends on such factors as the discrimination of the proving counter, the repeatability of the dete
49、ctors, and the repeatability required of the proving system as a whole. At least 10,000 whole meter pulses are required for Meter Factors (MFs) derived to a resolution of 0.0001. The relationship between the flow range of the meter and the reference volume must also be taken into account. For provers that do not accumulate a minimum of 10,000 whole meter pulses between detectors for each pass of the displacer, meter pulse discrimination using pulse interpolation tech-niques is required (see API MPMS Chapter 4.6).1.1 SCOPEThis chapter outlines the essential elements of provers that do,
