Manual of Petroleum Measurement Standards

Chapter 7—Temperature

Determination

Section 4—Dynamic Temperature Measurement

SECOND EDITION, JANUARY 2018

Special Notes

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Users of this Standard should not rely exclusively on the information contained in this document. Sound business, scientific, engineering, and safety judgment should be used in employing the information contained herein.

Users of Instructions should not rely exclusively on the information contained in this document. Sound business, scientific, engineering, and safety judgment should be used in employing the information contained herein.

Where applicable, authorities having jurisdiction should be consulted.

API is not undertaking to meet the duties of employers, manufacturers, or suppliers to warn and properly train and equip their employees, and others exposed, concerning health and safety risks and precautions, nor undertaking their obligations to comply with authorities having jurisdiction.

Information concerning safety and health risks and proper precautions with respect to particular materials and conditions should be obtained from the employer, the manufacturer or supplier of that material, or the material safety data sheet.

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Copyright © 2018 American Petroleum Institute

Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms and Definitions 2

4. Acronyms 2

5. General Precautions 3

   1. Introduction 3

   2. Safety 3

   3. Equipment Precautions 3

6. Equipment and Design Requirements 4

   1. General 4

   2. Minimum Acceptable Resolution 4

   3. Thermowell 5

   4. Digital Thermometer 8

7. Installation Requirements 8

   1. General 8

   2. Meters 9

   3. Provers 10

   4. Test Facilities 11

   5. Signal Transmission to Remote Readout 11

8. Procedures for Temperature Determination 12

   1. General 12

   2. Temperature Measurement for Prover Calibration 12

   3. Temperature Measurement for Meter Proving 12

   4. Temperature Measurement for Online Density Meter Proving 12

   5. Temperature Measurement for Meter Ticket 13

   6. Use of Manual Measurement 13

9. Accuracy Requirements 13

   1. Accuracy of Temperature Measurement Devices 13

   2. Total Accuracy of the Dynamic Temperature Measurement 15

10. Inspection, Verification, and Calibration Requirements 15

    1. General 15

    2. Traceability 15

    3. Inspection 15

    4. Verification 16

    5. Calibration 18

    6. Certification 20

Annex A (normative) Comparison of Inspection, Verification, and Calibration Requirements 21

Bibliography 26

Tables

1. Minimum Resolution of Reading 5

2. Minimum Accuracy Requirements of Temperature Devices 14

A.1 Comparison of Inspection, Verification and Calibration Requirements 22

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Introduction

The purpose of this standard is to describe the measurement practice to accurately determine the temperature of liquid hydrocarbons under dynamic (i.e. flowing) conditions. The accurate measurement of temperature is essential to accurately determine the average temperature of the hydrocarbon liquid transferred, for the purpose of obtaining the temperature and pressure volume correction factors (refer to API MPMS Chapter 11.1) to calculate the volume at standard conditions.

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Chapter 7—Temperature Determination Section 4—Dynamic Temperature Measurement

1. Scope

   This standard describes methods, equipment, installation, and operating procedures for the proper determination of the temperature of hydrocarbon liquids under dynamic conditions in custody transfer applications. This standard describes the accuracy requirement and the calibration of the temperature measurement equipment.

   
   

   This standard does not cover dynamic temperature measurement of refrigerated, light hydrocarbon fluids or cryogenic liquids.

   
   

2. Normative References

The following standards and other industry publications contain provisions that, through reference in this text, constitute provisions of this standard. All standards are subject to revision, and parties to agreements based on this standard are encouraged to use the most recent editions of the standards indicated below:

API Manual of Petroleum Measurement Standards (MPMS)

• Chapter 1, Terms and Definitions, https://chapter1.api.org

  
  

• Chapter 4 (All Relevant Sections), Proving Systems

  
  

• Chapter 5 (All Relevant Sections), Metering Systems

  
  

• Chapter 6 (All Relevant Sections), Metering Assemblies

  
  

• Chapter 7.1, Liquid in Glass Thermometers

  
  

• Chapter 12.2, Calculation of Liquid Petroleum Quantities Using Dynamic Measurement Methods

  
  

• Chapter 21.2, Electronic Liquid Volume Measurement Using Positive Displacement and Turbine Meters

API Recommended Practice 500, Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I Division 1 and Division 2

API Recommended Practice 2003, Protection Against Ignitions Arising Out of Static, Lighting, and Stray Currents

ASME 1

ASME PTC 19.3TW_2016, American National Standard for Thermowells

ASTM 2

• ASTM E1, Standard Specification for ASTM Thermometers

  
  

• ASTM E77, Standard Test Method for Inspection and Verification of Liquid-in-glass Thermometers

  
  

• ASTM E344, Terminology Relating to Thermometry and Hydrometry

1. American Society of Mechanical Engineers, Two Park Avenue, New York, NY 10016-5990

2. ASTM International, 100 Barr Harbor Drive, West Conshohocken, Pennsylvania 19428, www.astm.org

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