Foreword
Introduction
1 Scope
2 References
2.1 Normative references
2.2 Informative references
3 Definitions and symbols
3.1 Definitions
3.1.1 General
3.1.2 Quantities
3.1.3 Meter design
3.1.4 Thermodynamic conditions
3.1.5 Statistics
3.1.6 Flow rates
3.2 Symbols and subscripts
3.3 Abbreviations
4 Principles of measurement
4.1 Basic formulas
4.2 Factors affecting performance
4.3 Description of generic types
4.3.1 General
4.3.2 Transducers
4.3.3 Meter body and acoustic path configurations
4.4 Contributions to the uncertainty in measurement
4.5 USM Classification
4.6 Reynolds number
4.7 Temperature and pressure correction
4.7.1 Introduction
4.7.2 Correction for the temperature
4.7.3 Pressure correction
4.7.4 Effects of Transducer ports
4.7.5 Total metering error
4.7.6 Detailed calculation procedure
5 Meter characteristics
5.1 Operating conditions
5.1.1 Flow rates/gas velocities
5.1.2 Pressure
5.1.3 Temperature
5.1.4 Gas quality
5.2 Meter body/materials/construction
5.2.1 Materials
5.2.2 Meter Body
5.2.3 Connections
5.2.4 Dimensions
5.2.5 Ultrasonic transducer ports
5.2.6 Pressure tappings
5.2.7 Anti roll provision
5.2.8 Flow conditioner
5.2.9 Markings
5.2.10 Corrosion protection
5.3 Transducers
5.3.1 Specification
5.3.2 Rate of pressure change
5.3.3 Transducer characterization
5.3.4 Path configuration
5.3.5 Marking
5.3.6 Cable
5.4 Electronics
5.4.1 General requirements
5.4.2 Power supply
5.4.3 Pulse detection method
5.4.4 Sampling/pulsating flow
5.4.5 Signal to noise ratio
5.4.6 Processing of data
5.4.7 Output
5.4.8 Cable jackets and insulation
5.4.9 Marking
5.5 Software
5.5.1 Firmware
5.5.2 Discontinuity
5.5.3 Marking and version-management
5.5.4 Configuration and Monitoring Software
5.5.5 Inspection and Verification Functions
5.5.6 Diagnostic parameters
5.6 Exchange of components
5.7 Determination of density
5.7.1 General
5.7.2 Pressure measurement
5.7.3 Temperature measurement and density measurement
5.8 Performance requirements
5.8.1 Accuracy requirements for Class 1 meters
5.8.2 Accuracy requirements for Class 2 meters
5.8.3 Pressure, Temperature, and Gas Composition Influences
5.9 Operation and installation requirements
5.9.1 General
5.9.2 Operational requirements
5.9.3 Installation requirements and flow profile
considerations
5.9.4 Manual handling and transportation
6 Test and calibration
6.1 Pressure testing and Leakage Testing
6.2 Individual testing - Static testing
6.2.1 General
6.2.2 Geometrical parameters
6.2.3 Timing and time delays
6.2.4 Zero Flow Verification Test
6.3 Individual Testing - Flow Calibration
6.3.1 General
6.3.2 Laboratory flow calibration
6.3.3 Judging the measurement quality of the meter
6.3.4 Calculation of Flow Weighted Mean Error (FWME)
6.3.5 Adjustment factors
6.4 Type testing, ensuring measurement quality in the field
6.4.1 General
6.4.2 Accuracy
6.4.3 Installation conditions
6.4.4 Path failure simulation and exchange of components
6.4.5 Electronics design testing
7 Audit trail and Operational practice
7.1 General
7.2 Verification process
7.3 Into operation
7.4 Operational diagnostics
7.4.1 Speed-of-sound
7.5 Audit trail during operation; Inter comparison and Inspection
7.5.1 Inter-Comparison Checks
7.5.2 Inspections
7.6 Recalibration
7.6.1 General
7.6.2 Recalibration interval
7.6.3 Field recalibration
7.6.4 As-found laboratory recalibration
7.6.5 Consequences and aftercare
7.7 Total operational uncertainty
8 Valve characterization and noise in a metering & regulating
station
8.1 Introduction
8.2 The calculation method
8.2.1 General
8.2.2 The generation of the noise by the control valve:
8.2.3 The propagation of the noise from the valve to the
USM (Nd)
8.2.4 The signal strength of the USM (ps)
8.2.5 The signal to noise ratio at the USM
8.2.6 M&R station design
Annex A (informative) Registration of Error Bands
A.1 General
A.2 Mismeasurement example
Annex B (informative) Derivation and correction of USM errors
B.1 Methods for correcting a USM's flow measurement error
B.2 Example of a flow weighted mean error (FWME) calculation
Annex C (informative) The Reference Meter Method for USM's In Series
Annex D (informative) Documents
Annex E (informative) Detailed calculation of geometry related
temperature and pressure corrections
E.1 General background
E.2 Direct Calculation Step 1 - Body Temperature Effect
E.4 Direct Calculation Step 3 - Correction for body style
effect or proximity to flanges
E.5 Direct Calculation Step 4 - Combined pressure correction
effect
E.6 Direct Calculation Step 5 - Expansion effects in the
transducer ports
E.7 Direct Calculation Step 6 - Combined Flow Correction
E.8 Guidance on the use of Finite Element (FE) Models
E.9 Note on intentional use of thin-wall equations beyond
their normal limit
E.10 Calculation of an initial estimate for the body pressure
effect
E.11 Worked Example
E.11.1 Meter details
E.11.2 Initial flow error estimate
E.11.3 Common elements to detailed calculation
E.11.4 Direct single-stage detailed calculation
E.11.5 Three-stage detailed calculation
E.12 Observations on the example calculation
Annex F (informative) Disturbance tests
Annex G (informative) Bibliography