S-G-03–Specifications for the approval of type of gas metering devices–Part 9

Category: Gas
Issue date:
Effective date:
Revision number: 3
Supersedes: S-G-03 (rev. 2)


Part 9: Cone-shaped differential pressure meters

Table of contents


1.0 Scope

This part of the Specifications applies to cone-shaped differential pressure (CSDP) meters.

2.0 Unit requirements

Note: The following requirements of Part 1, section 1.0 apply:

  • 1.1 Use of units
  • 1.2 Metric units of measure

3.0 Metrological requirements

Notes: The following requirements of Part 1, section 2.0 apply:

  • 2.1 Rated operating conditions (except g)
  • 2.3 Maximum permissible errors
  • 2.4 Weighted mean error
  • 2.5 Repeatability
  • 2.6 Working pressure
  • 2.7 Temperature
  • 2.9 Vibrations and shocks
  • 2.10 Orientation
  • 2.12 Flow disturbance

According to the characteristics of the meter, the following requirements may also apply:

  • 2.14 Different gases
  • 2.15 Influences from ancillary devices

3.1 Maximum permissible error

The error of registration must not exceed a maximum permissible error (MPE) of ± 1% within the Reynolds number range.

3.2 Algorithm

The algorithm used to translate the primary measurements of pressure and temperature into volumetric flow must be the algorithm derived in Appendix A.

Note: Where the applicant can show sufficient evidence that an alternative algorithm is suitable, that algorithm may be authorized for use in the notice of approval.

4.0 Technical requirements

4.1 Pressure tap

A static pressure tap must be located on the meter body.

5.0 Marking requirements

Notes: The following requirements of Part 1, section 4.0 apply:

  • 4.1 Permanency and legibility
  • 4.2
    • (a) Departmental approval number
    • (b) Manufacturer's name or registered trademark
    • (c) Model or type designation
    • (d) Serial number
    • (e) Ambient temperature range, where less than -30 °C to 40 °C
    • (f) Pmin (where applicable) and Pmax
    • (j) Gas temperature range for which the errors ≤ MPE
  • 4.6 Unidirectional flow measurement
  • 4.12 Inspection number
  • 4.13 Verification marks

According to the characteristics of the meter, the following requirement may also apply:

  • 4.3 Bar codes or quick response codes

5.1 General

The following information must be indelibly marked on the meter or on a nameplate permanently affixed to the meter:

  • Reynolds numbers range;
  • Beta ratio;
  • Inside diameter of the meter tube; and
  • Meter's material type or thermal expansion coefficient as well as the reference temperature associated with the inside diameter of the meter tube.

6.0 Sealing requirements

Note: The requirement of Part 1, sub-section 5.1 apply.

7.0 Administrative requirements

Note: The requirements of Part 1, section 6.0 apply.

8.0 Performance test requirements

Note: Test conditions and performance tests can be obtained by contacting MC.

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