Manual of Petroleum Measurement Standards Chapter 4.8

Operation of Proving Systems

SECOND EDITION, SEPTEMBER 2013

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms and Definitions 1

4. Basic Principles 2

5. The Need to Prove 2

6. Frequency of Meter Proving 2

7. General Considerations for Meters and Provers 3

   1. General 3

   2. Data Recording 3

   3. Temperature and Pressure Measurements 3

   4. Operating Pressure 4

   5. Density 4

   6. Proving Meters with Pulse Output 4

   7. Proving Meters Utilizing Totalizers 4

8. Proving Locations 5

   1. General 5

   2. In Situ Proving 5

   3. Laboratory Proving 5

   4. Ex Situ Proving 5

9. Types of Provers 5

   1. General 5

   2. Displacement Provers 6

   3. Tank Prover 8

   4. Master Meter Prover 9

10. Prover Calibration Frequency 10

    1. Displacement and Tank Provers 10

    2. Master Meter Provers 11

11. Proving Methods 12

    1. Volumetric Proving 12

    2. Direct Mass Proving 12

    3. Inferred Mass Proving 13

12. Assessment of Proving Results 13

    1. The Number of Runs 13

    2. Meter Factor 13

    3. Application of Meter factors 14

13. Proving Concerns 14

    1. Flow Conditioning 14

    2. Temperature and Pressure Variations 15

    3. Viscosity Variation 15

    4. Valve(s) Leakage 15

    5. Displacer Slippage 16

    6. Meter Wear 16

    7. Effect of Electrical Disturbance 16

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       Contents

       Page

    8. Flow Rate Variation 16

    9. Meter Registration (Head) Check 16

    10. Meter and Prover Design 17

    11. Meter and Prover Combinations 17

    12. Air/Vapor in the Proving System 17

    13. Cavitation 17

    14. Debris and Coating 17

    15. Physical Damage 17

    16. Computational Master Meter Provers Zero 18

Annex A (normative) Evaluating Meter Proving Data 19

Annex B (normative) Method for Determining the Frequency of Calibrating Provers 22

Annex C (informative) Meter Prover Operation 25

Annex D (informative) Proving Form Examples 36

Bibliography 40

Figures

1. Proving Example—Inferred Mass Proving 37

2. Proving Example—Direct Mass Proving 38

3. Proving Example—Volumetric Proving 39

Tables

1. Repeatability Criteria for 0.027 % Uncertainty (Preferred Uncertainty)

   For ±0.00027 Random Uncertainty in Average Meter Factor 20

2. Repeatability Criteria for 0.073 % Uncertainty (Limited Volume Proving)

For ±0.00073 Random Uncertainty in Average Meter Factor 21

1. Prover Calibration Frequency Example 23

2. Example Table—Dynamic or Tank Prover Calibration Frequency

   For 0.06 % Volume Change Benchmark 24

3. Determining the Frequency of Prover Calibration 24

1. Repeatability Criteria for 0.027 % Uncertainty

   For ±0.00027 Random Uncertainty in Average Meter Factor 34

2. Suggested Minimum Prover Volume for ±0.027 % Uncertainty of Meter Factor

when Proving Ultrasonic Flow Meters 35

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Introduction

This guide is intended to provide essential information on the operation of the various meter proving systems used in the petroleum industry.

In the petroleum industry, the term proving is used to refer to the testing of liquid petroleum meters. A meter is proved by comparing a known prover volume (mass) to an indicated meter volume (mass). For volume proving, the meter and prover volumes are subjected to a series of calculations using correction factors to convert volumes to standard conditions for the effects of temperature and pressure to establish a meter factor. For mass proving, the prover volume is converted to prover mass by the measurement or calculation of density at the prover in order to compare the meter mass to the prover mass, or by the use of a Coriolis master meter, to establish a meter factor.

Liquid petroleum meters used for custody transfer measurement require periodic proving to verify accuracy and repeatability and to establish valid meter factors.

Displacement, master meter, and tank provers vary in size and may be permanently installed or mobile. These prover types are described in their respective section API Manual of Petroleum Measurement Standards Chapter 4, Proving Systems.

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Operation of Proving Systems

1. Scope

   This guide provides information for operating meter provers on single-phase liquid hydrocarbons. It is intended for use as a reference manual for operating proving systems.

   
   

   The requirements of this chapter are based on customary practices for single-phase liquids. This standard is primarily written for hydrocarbons, but much of the information in this chapter may be applicable to other liquids. Specific requirements for other liquids should be agreeable to the parties involved.

   
   

2. Normative References

   The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

   
   

   API MPMS Chapter 4.2, Displacement Provers

   
   

   API MPMS Chapter 4.4, Tank Provers

   
   

   API MPMS Chapter 4.5, Master-Meter Provers

   
   

   API MPMS Chapter 4.6, Pulse Interpolation

   
   

   API MPMS Chapter 5.1, General Considerations for Measurement by Meters

   
   

   API MPMS Chapter 5.2, Measurement of Liquid Hydrocarbons by Displacement Meters

   
   

   API MPMS Chapter 5.3, Measurement of Liquid Hydrocarbons by Turbine Meters

   
   

   API MPMS Chapter 5.4, Accessory Equipment for Liquid Meters

   
   

   API MPMS Chapter 5.5, Fidelity and Security of Flow Measurement Pulsed-Data Transmission Systems

   
   

   API MPMS Chapter 5.6, Measurement of Liquid Hydrocarbons by Coriolis Meters

   
   

   API MPMS Chapter 5.8, Measurement of Liquid Hydrocarbons by Ultrasonic Flow Meters Using Transit Time Technology

   
   

   API MPMS Chapter 7.2, Dynamic Temperature Determination

   
   

   API MPMS Chapter 12. 2, (all parts) Calculation of Petroleum Quantities Using Dynamic Measurement Methods and Volumetric Correction Factors

   
   

   API MPMS Chapter 13.1, Statistical Concepts and Procedures in Measurement

   
   

   API MPMS Chapter 13.2, Statistical Methods of Evaluating Meter Proving Data

   
   

3. Terms and Definitions

No definitions are unique to this document.

1