1 Scope
This regulation is applicable to the type evaluation, initial verification, subsequent verification and in-service inspection of ultrasonic flowmeter (hereinafter referred to as flowmeter) for closed pipeline follows the principle of time difference method.
This regulation is not applicable to the verification of flowmeter measuring the flow in open or covered channel.
2 Reference Documents
The following standards and regulations contain provisions which, through reference in this text, constitute provisions of this regulation.
JJF 1001-1998 General Terms in Metrology and Their Definitions
JJF 1004-2004 Metrological Terms and Their Definitions for Flow Rate
GB 3836 Electrical Apparatus for Explosive Gas Atmospheres
GB/T 18604-2001 Measurement of Natural Gas Flow by Ultrasonic Flow Meters
GB 17820-1999 Natural Gas
GB 50251-2003 Code for Design of Gas Transmission Pipeline Engineering
GB/T 13609-1999 Natural Gas - Sampling Guidelines
GB/T 13610-2003 Analysis of Natural Gas by Gas Chromatography
GB/T 17747.2-1999 Natural Gas - Calculation of Compression Factor - Calculation Using Molar-composition Analysis
ISO 17089:2004 (CD) Measurement of Fluid Flow in Closed Conduits - Ultrasonic Meters for Gas; Meters for Fiscal and Allocation Measurement
ISO/TR 12765:1997 Measurement of Fluid Flow in Closed Conduits - Methods Using Transit Time Ultrasonic Flowmeters
AGA Report-1992 No.8 Compressibility Factors of Natural Gas and Other Related Hydrocarbon Gases
AGA Report No.9-1998 Measurement of Gas by Multipath Ultrasonic Meters
AGA Report No.10-2003 Speed of Sound in Natural Gas and Other Related Hydrocar-bon Gases
ANSI/API MPMS 5.8-2004 Measurement of Liquid Hydrocarbons by Ultrasonic Flowmeters Using Transit Time Technology
Editions of such documents which are applied shall be those currently in effect.
3 Terminologies and Definitions
3.1 Ultrasonic flowmeter
1 Scope
2 Reference Documents
3 Terminologies and Definitions
4 General
4.1 Operating Principle
4.2 Structure Type
5 Metrological Performance Requirements
5.1 Accuracy Grade
5.2 Repeatability
5.3 Meter Factor Adjustment
5.4 Requirements of Bi-direction Measurement Flowmeter
5.5 Requirements of Clamp-on Meter
6 General Technical Requirements
6.1 Random Documents
6.2 Nameplate and Marking
6.3 Appearance
6.4 Protective Function
6.5 Tightness
7 Measuring Instrument Control
7.1 Verification Condition
7.2 Test Item and Test Method
7.3 Verification Result Treatment
7.4 Verification Period
Appendix A Type Evaluation of Ultrasonic Flowmeter
Appendix B Special Requirements for Site Verification
Appendix C In-service Inspection
Appendix D Installation Requirements of Ultrasonic Flowmeter
Appendix E Verification Certificate (Inside Page) Format
