BS 7965:2000

Committees responsible
Foreword
1 Scope
2 Normative references
3 Symbols and abbreviations
4 Selection
5 Installation recommendations
6 Operational consideration
7 Ultrasonic flowmeter certification
Annex A (informative) Uncertainty calculation for
                      ultrasonic flow meters
Annex B (informative) Performance specification
Annex C (informative) Derivation and correction of flow
                      measurement errors
Bibliography
Figure 1 - General ray geometry for transit time velocity
           measurement
Figure 2 - Intrusive a) and non-intrusive b) transducer
           designs
Figure 3 - Variations in path configuration
Figure 4 - Some typical cross-sectional acoustic path
           configurations
Figure 5 - Performance specification summary
Figure B.1 - Performance specification for class 1 meters
Figure B.2 - Performance specification for class 2 meters
Figure B.3 - Performance specification for class 3 meters
Figure B.4 - Performance specification for class 4 meters
Figure C.1 - Un-corrected and WME-corrected flow calibration
             data plot for 200 mm diameter USM
Table 1 - USM Classification
Table 2 - Installation criteria
Table 3 - Internal diameter tolerances
Table 4 - Uncertainty tolerances for beam path lengths
Table 5 - Nominal test flow rates
Table C.1 - Flow calibration data table for 200 mm diameter
            USM
Table C.2 - Flow weighted mean error calculation summary for
            200 mm diameter USM
Table C.3 - "WME-corrected" flow calibration data summary
            for a 200 mm diameter USM

Supplies a guide to the installation, selection, calibration and operation of diagonal path transit time gas ultrasonic flowmeters (USMs) for industrial gas applications. Only applies to devices where the entire gas stream flows through the body of the USM and the transducers are in contact with the fluid (wetted or invasive type). Includes full-bore and insertion type meters employing reflective or direct paths, and covers "dirty gases", i.e, gas that has been contaminated with solids and/or liquids in small quantities. Does not apply to clamp-on/externally mounted meters.