1 Scope
This standard specifies the technical requirements in aspects of design, establishment, operation and maintenance of trade measuring system in constructed, reconstructed and extended natural gas measuring stations. The quality of natural gas transmitted shall meet the requirements of GB 17820.
This standard is applicable to the trade measuring system of natural gas measuring station with design through capacity no less than 100m3/h (under standard reference conditions) and operating pressure no less than 0.1MPa (gauge pressure).
This standard doesn't cover all safety concerns related to its application. It is the responsibility of the user of this standard to establish corresponding safety and protection measures and determine the limited application scope prior to use.
2 Normative References
The following documents for the application of this document are essential. Any dated reference, just dated edition applies to this document. For undated references, the latest edition of the normative document (including any amendments) applies.
GB 3836.1 Explosive Atmospheres - Part 1: Equipment - General Requirements
GB/T 5274 Gas Analysis - Preparation of Calibration Gas Mixture - Gravimetric Method
GB/T 10248 Gas Analysis - Preparation of Calibration Gas Mixture - Static Volumetric Methods
GB/T 11062 Natural Gas - Calculation of Calorific Values, Density, Relative Density and Wobbe Index
GB/T 13609 Natural Gas Sampling Guidelines
GB/T 13610 Analysis of Natural Gas Composition - Gas Chromatography
GB 13837 Sound and Television Broadcast Receivers and Associated Equipment - Radio Disturbance Characteristics - Limits and Methods of Measurement
GB/T 14023 Vehicles Boats and Internal Combustion Engine Driven Devices - Radio Disturbance Characteristics - Limits and Methods of Measurement
GB/T 17281 Determination of Hydrocarbons from Butane (C4) to Hexadecane (C16) in Natural Gas - Gas Chromatographic Method
GB/T 17626.1 Electromagnetic Compatibility - Testing and Measurement Techniques - Overview of Immunity Tests
GB/T 17626.3 Electromagnetic Compatibility - Testing and Measurement Techniques - Radiated Radio-frequency Electromagnetic Field Immunity Test
GB/T 17626.6 Electromagnetic Compatibility - Testing and Measurement Techniques - Immunity to Conducted Disturbances, Induced by Radio-frequency Fields
GB/T 17626.9 Electromagnetic Compatibility - Testing and Measurement Techniques - Pulse Magnetic Field Immunity Test
GB/T 17743 Limits and Methods of Measurement of Radio Disturbance Characteristics of Electrical Lighting and Similar Equipment
GB/T 17747 (all parts) Natural Gas - Calculation of Compression Factor
GB 17820 Natural Gas
GB/T 18604 Measurement of Natural Gas Flow by Gas Ultrasonic Flow Meters
GB/T 19000 Quality Management Systems - Fundamentals and Vocabulary
GB/T 21391 Measurement of Natural Gas Flow by Turbine Meters
GB/T 21446 Measurement of Natural Gas Flow by Means of Standard Orifice Meter
GB/T 22723-2008 Energy Determination for Natural Gas
GB 50251 Code for Design of Gas Transmission Pipeline Engineering
GB/T 50540-2009 Standard for Construction and Acceptance of Oil and Natural Gas Station Procedure Pipeline Project
SY/T 6658 Measurement of Natural Gas Flow by Vortex Precession Meter
SY/T 6659 Measurement of Natural Gas by Coriolis Meter
SY/T 6660 Measurement of Natural Gas Flow by Rotary Displacement Gas Meters
JJG 700 Verification Regulation of Gas Chromatograph
JJG 1003 Verification Regulation of Integration Meters
JJG 1055 On-line Gas Chromatograph
ISO 10723 Natural Gas - Performance Evaluation for On-line Analytical Systems
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
3.1
measuring station
facility used for trade measuring of natural gas, which is composed of inlet and outlet pipelines, block valve and other instruments and can be isolated
3.2
Foreword III
1 Scope
2 Normative References
3 Terms and Definitions
4 Physical Principles and General Requirements
4.1 Standard Reference Conditions
4.2 Flow Measurement
4.3 Calorific Value Measurement
4.4 Energy Measurement
4.5 Assurance for Continuous Gas Transmission
4.6 Ambient Conditions
4.7 Safety
4.8 Quality Management System
5 Design and Establishment
5.1 Design
5.2 Establishment of Measuring Station
6 Calorific Value Measurement
6.1 General
6.2 Measurement System
6.3 Performance Requirements
6.4 Operation and Maintenance
6.5 Assignment
7 Reliability and Calibration of Natural Gas Measuring System
7.1 Accuracy Requirements
7.2 Installation Requirements
8 Commissioning and Test Run
8.1 General
8.2 Test Equipment
8.3 Test Run
8.4 Test and Calibration Procedures
9 Acceptance
9.1 General
9.2 Post-commissioning Inspection
10 Operation and Maintenance
10.1 General
10.2 Flow Meter
10.3 Conversion Device
10.4 Inspection after Maintenance
10.5 Consistency
10.6 Data and Files
Annex A (Informative) Calculation Formulae of Natural Gas Volume, Mass and Energy
A.1 General
A.2 Calculation of Volume
A.3 Calculation of Mass
A.4 Calculation of Energy
Annex B (Normative) Equipment Guideline of Instruments and Meters
B.1 Measuring System
B.2 Supporting Meters
Annex C (Informative) Selection Guideline of Flow Meter Type
C.1 Selection Guideline of Flow Meter Type
Annex D (Informative) Performance Characteristics of Measuring System
D.1 General
D.2 Technical Requirements for Accuracy of Measurement Meter
D.3 Accuracy Requirements: Maximum Permissible Error (MPE)
D.4 Example of Uncertainty Evaluation
Annex E (Informative) Test Procedure for Supporting Meters
E.1 Differential Pressure Sensor
E.2 Pressure Sensor
E.3 Temperature Sensor
Annex F (Informative) Files and Records
F.1 Files
F.2 Records
F.3 File Confirmation
Bibliography
Figure D.1 Change of the Maximum Permissible Error over Time - without Recalibration
Figure D.2 Change of the Maximum Permissible Error over Time - Pressure Sensor, Recalibrated once every 2 Years
Figure D.3 Change of the Maximum Permissible Error over Time - Pressure Sensor Recalibrated every 2 Years and Flow Meter Recalibrated every 6 Years
Table A.1 Symbols and Codes
Table B.1 Measuring System of Different Grades
Table B.2 Accuracy of Supporting Meters of Measuring System
Table C.1 Selection Guideline of Flow Meter Type
Table D.1 Symbols and Codes
Table D.2 Examples of Uncertainty Parameters
Table D.3 Uncertainty of the Change of Values in Table D.2 over Time
