1、Manual of PetroleumMeasurement StandardsChapter 4Proving SystemsSection 4Tank ProversSECOND EDITION, MAY 1998REAFFIRMED, SEPTEMBER 2010Manual of PetroleumMeasurement StandardsChapter 4Proving SystemsSection 4Tank ProversMeasurement CoordinationSECOND EDITION, MAY 1998REAFFIRMED, SEPTEMBER 2010SPECIA
2、L 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 employers, manufacturers, or suppliers towarn and properly train and equ
3、ip their employees, and others exposed, concerning healthand safety risks and precautions, nor undertaking their obligations under local, state, or fed-eral laws.Information concerning safety and health risks and proper precautions with respect to par-ticular materials and conditions should be obtai
4、ned from the employer, the manufacturer orsupplier of that material, or the material safety data sheet.Nothing contained in any API publication is to be construed as granting any right, byimplication or otherwise, for the manufacture, sale, or use of any method, apparatus, or prod-uct covered by let
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6、ars will be added to this reviewcycle. This publication will no longer be in effect five years after its publication date as anoperative API standard or, where an extension has been granted, upon republication. Statusof the publication can be ascertained from the API Measurement Coordination Departm
7、enttelephone (202) 682-8000. A catalog of API publications and materials is published annu-ally and updated quarterly by API, 1220 L Street, N.W., Washington, D.C. 20005.This document was produced under API standardization procedures that ensure appro-priate notification and participation in the dev
8、elopmental process and is designated as anAPI standard. Questions concerning the interpretation of the content of this standard orcomments and questions concerning the procedures under which this standard was devel-oped should be directed in writing to the Measurement Coordinator, American Petroleum
9、Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to repro-duce or translate all or any part of the material published herein should also be addressedto the director.API standards are published to facilitate the broad availability of proven, sound engineer-ing and opera
10、ting practices. These standards are not intended to obviate the need for apply-ing sound engineering judgment regarding when and where these standards should beutilized. The formulation and publication of API standards is not intended in any way toinhibit anyone from using any other practices.Any ma
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13、L Street, N.W., Washington, D.C. 20005.Copyright 1998 American Petroleum InstituteFOREWORDChapter 4 of the Manual of Petroleum Measurement Standardswas prepared as a guidefor the design, installation, calibration, and operation of meter proving systems commonlyused by the majority of petroleum opera
14、tors. The devices and practices covered in this chap-ter may not be applicable to all liquid hydrocarbons under all operating conditions. Othertypes of proving devices that are not covered in this chapter may be appropriate for use ifagreed upon by the parties involved.The information contained in t
15、his edition of Chapter 4 supersedes the information con-tained in the previous edition (First Edition, May 1978), which is no longer in print. It alsosupersedes the information on proving systems contained in API Standard 1101, Measure-ment of Petroleum Liquid Hydrocarbons by Positive Displacement M
16、eter(First Edition,1960); API Standard 2531, Mechanical Displacement Meter Provers; API Standard 2533,Metering Viscous Hydrocarbons; 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
17、 United States and is related to thestandards, specifications, and procedures of the National Institute of Standards and Technol-ogy (NIST). When the information provided herein is used in other countries, the specifica-tions and procedures of the appropriate national standards organizations may app
18、ly. Whereappropriate, other test codes and procedures for checking pressure and electrical equipmentmay be used.For the purposes of business transactions, limits on error or measurement tolerance areusually set by law, regulation, or mutual agreement between contracting parties. This publi-cation is
19、 not intended to set tolerances for such purposes; it is intended only to describemethods by which acceptable approaches to any desired accuracy can be achieved. Chapter 4now contains the following sections:Section 1, “Introduction” Section 2, “Conventional Pipe Provers” Section 3, “Small Volume Pro
20、vers” Section 4, “Tank Provers” Section 5, “Master-Meter Provers” Section 6, “Pulse Interpolation” Section 7, “Field-Standard Test Measures” Section 8, “Operation of Proving Systems”API publications may be used by anyone desiring to do so. Every effort has been made bythe Institute to assure the acc
21、uracy and reliability of the data contained in them; however, theInstitute makes no representation, warranty, or guarantee in connection with this publicationand hereby expressly disclaims any liability or responsibility for loss or damage resultingfrom its use or for the violation of any federal, s
22、tate, or municipal regulation with which thispublication may conflict.Suggested revisions are invited and should be submitted to the Measurement Coordinator,American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005.iiiCONTENTSPage1 INTRODUCTION . . . . . . . . . . . . . . . . . . . .
23、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 REFERENCED PUBLICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24、. . . . . . 14 EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.1 General Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.2 Valves . . . . . . . . . . . . . . . .
25、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.3 Wiring and Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.4 Safety Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、 . . . . . . . . . . . . . . . 14.5 Closed Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24.6 Necks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24.7 Counters/Regi
27、sters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 DESIGN AND CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.1 General Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28、 . . . . . . . . . . . . . . 25.2 Temperature Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.3 Pressure Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.4 Prover Capacity . . . . . . . . . .
29、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.5 Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.6 Gauge Glasses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30、. . . . . . . . . . . . . . . 46 TANK PROVER CALIBRATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46.1 General Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46.2 Procedural Uncertainty in Prover Calibr
31、ation. . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.3 Temperature Stability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76.4 Calibration by the Waterdraw Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76.5 Calibra
32、tion by the Master-Meter Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.6 Temperature Corrections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.7 Determining a Tank Prover Volume Under Pressure . . . . . . . . . . . . . . . . . .
33、. . . 10Figures1 Closed Stationary Tank Prover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Open Stationary Prover Tank (Drain-to-Zero or Bottom Gauge-Glass Type) . . . . 43 Schematic Operating Diagram of Volumetric Prover for Vapor Displacement . . . 54 Porta
34、ble Prover (Drain-to-Zero or Bottom Gauge-Glass Type) . . . . . . . . . . . . . . . 65 Open Portable Prover Tank With Pump Assembly . . . . . . . . . . . . . . . . . . . . . . . . . 7Tables1 Capillary Rise in Glass Tubes with Varying Water Quality . . . . . . . . . . . . . . . . . . 42 Estimated Sta
35、ndard Deviation of Average Tank Prover Calibration Sets . . . . . . . . 63 Uncertainty of the Average at the 95% Confidence Level of Prover Calibration Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6v1Chapter 4Proving SystemsSection 4T
36、ank Provers1 Introduction Throughout this chapter a prover tank shall be consideredan open or closed volumetric measure that generally has agraduated top neck and may have a graduated bottom neck.The volume is established between a shut-off valve or bot-tom-neck graduation and an upper-neck graduati
37、on.The requirements in this chapter are intended for crude oiland refined petroleum products. Meter proving requirementsfor other fluids should be appropriate for the overall custody-transfer accuracy and should be agreeable to the partiesinvolved.2 Scope This chapter specifies the characteristics o
38、f stationary(fixed) or portable tank provers that are in general use and theprocedures for their calibration. Guidelines are provided forthe design, manufacture, calibration and use of new and/orreplacement tank provers, and are not intended to make anyexisting tank provers obsolete.More specific de
39、sign criteria are available in NIST1Hand-book 105-3, Specifications and Tolerances for GraduatedNeck-Type Volumetric Field Standards(includes Provers, perSection 1.1 of NIST 105-3). Consideration must also be givento the requirements of any weights and measures authoritythat may be involved.3 Refere
40、nced Publications The current editions of the following standards, codes, andspecifications are cited in this chapter: API Manual of Petroleum Measurement Standards Chapter 1VocabularyChapter 4Proving SystemsChapter 5MeteringChapter 7Temperature DeterminationChapter 11Physical Properties DataChapter
41、 12Calculation of Petroleum QuantitiesChapter 13Statistical Aspects of Measuring andSamplingNIST1Handbook 105-3Specifications and Tolerances for Grad-uated Neck-Type Volumetric FieldStandards4 Equipment 4.1 GENERAL CONSIDERATIONS All components of the tank prover installation, includingconnecting pi
42、ping, valves, and manifolds, shall be in accor-dance with applicable pressure codes. Once a closed tank prover is on stream, it becomes part ofthe pressure system. Provisions should be made for expansionand contraction, vibration, reaction to pressure surges, andother process conditions. Considerati
43、on should be given tothe installation of valving to isolate the tank prover from linepressure when the system is not in use or during maintenance.All closed tank provers should be equipped with vent anddrain connections. Provisions should be made for the disposal of liquids and/orvapors that are dra
44、ined or vented from the tank prover. The dis-posal may be accomplished by pumping liquids or vapors backinto the system or by diverting them to a collecting point. Blind flanges or valve connections should be provided oneither side of a double block-and-bleed valve in the tankprover piping system. T
45、hese connections can serve as loca-tions for proving portable meters or as a means of calibratingthe tank prover by the master-meter or waterdraw method.4.2 VALVES All valves used in a tank prover system that can provide orcontribute to a bypass of liquid around the tank prover or themeter or to lea
46、kage between the tank prover and the metershall be double block-and-bleed valves, or the system shall beprovided with valves and piping that are the equivalent. Amethod for checking leakage in the valve system is required.4.3 WIRING AND CONTROLS All wiring devices and controls shall conform to the a
47、ppli-cable codes. Electrical controls and components should be located in aconvenient place for operation and maintenance.4.4 SAFETY DEVICES Safety relief valves, with discharge piping and leak detectionfacilities, shall be installed to control thermal expansion of theliquid in the tank prover and i
48、ts connecting piping while theyare isolated from the main stream. Automatic and remote con-trols should be protected with lockout switches or circuits orboth between remote and local panel locations to prevent acci-dental remote operation while a unit is being controlled locally. 1National Institute
49、 of Standards and Technology, Gaithersburg,Maryland 20899.2CHAPTER4PROVINGSYSTEMSSafety devices and locks should be installed to preventinadvertent operation of, or unauthorized tampering with,equipment. All automated or power-operated meter provingsystems should have emergency manual operators for useduring an accident or power failure. Grounding devices should be provided to protect againstelectrical shock or static discharge in both tank prover andelectrical instrumentation. 4.5 CLOSED SYSTEMS If the liquid to be measured by meter has a high vapor pres-sure, a closed tank proving
