Category: Gas
Issue date:
Effective date:
Revision number: 3
Supersedes: S-G-03 (rev. 2)
Part 4: Turbine meters
Table of contents
- 1.0 Scope
- 2.0 Unit requirements
- 3.0 Metrological requirements
- 4.0 Technical requirements
- 5.0 Marking requirements
- 6.0 Sealing requirements
- 7.0 Administrative requirements
- 8.0 Performance test requirements
1.0 Scope
This part of the Specifications applies to axial flow turbine type gas 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
- 2.2 Flow rate characteristics
- 2.3 Maximum permissible errors
- 2.4 Weighted mean error
- 2.5 Repeatability
- 2.6 Working pressure
- 2.7 Temperature
- 2.8 Durability
- 2.9 Vibrations and shocks
- 2.10 Orientation
- 2.11 Flow direction
According to the characteristics of the meter, the following requirements may also apply:
- 2.13 Drive shaft (torque)
- 2.14 Different gases
- 2.15 Influences from ancillary devices
3.1 Maximum permissible errors
The error of the unconverted volume registration must not exceed the MPE indicated below in Table 1.
Test conditions | Meter operating pressure type | Flow rate (Q) | MPE |
---|---|---|---|
Reference or "other than reference" | Meter intended for low operating pressure (i.e. < 400 kPa [≈50 psig]) | Qmin ≤ Q ≤ Qt (where Qt ≤ 0.2 Qmax) | ± 1.5% |
Qt ˂ Q ≤ Qmax (where Qt ≤ 0.2 Qmax) | ± 1.0% | ||
Meter intended for:
or
|
Qmin ≤ Q ≤ Qmax | ± 1.0% |
3.2 Effect of swirl
Where a swirl exists at the inlet of the meter, the error of the unconverted volume accumulation must not exceed ±1%.
Note: Meters not meeting the requirement in the two recommended configurations judged most likely to produce inaccurate measurement will not be considered for approval of type.
3.3 Measuring cartridge interchangeability
The fault due to measuring cartridge interchangeability must not be more than one third of the MPE applicable during evaluation, while the error must in no case exceed the MPE for that range.
4.0 Technical requirements
Notes: The following requirements of Part 1, section 3.0 apply:
- 3.1 Design, composition and construction
- 3.4 Case
- 3.5 Zero flow
- 3.6 Flow direction
- 3.7 Indication
- 3.12 Registration
According to the characteristics of the meter, the following requirements may also apply:
- 3.2 Minimum temperature range
- 3.3 Automatic volume conversion
- 3.8 Output
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
- (g) Qmax
- (h) Qmin
- (i) Qt
- (j) Gas temperature range for which the errors ≤ MPE
- 4.12 Inspection number
- 4.13 Verification marks
According to the characteristics of the meter, the following requirements may also apply:
- 4.3 Bar codes or quick response codes
- 4.4 Temperature converted volume
- 4.5 Pressure converted volume
- 4.6 Unidirectional flow measurement
- 4.7 Bidirectional flow measurement
- 4.8 Output drive shaft
- 4.14 Operating information
5.1 K factors and/or rotor factors
The K factors and/or rotor factors must be marked on the nameplate, where applicable.
5.2 Interchangeable cartridges
Where a meter is designed for operation with interchangeable cartridges, the markings required in Part 1, 4.2 (a to f), and subsection 4.6 must appear on the meter case and the interchangeable cartridge.
5.3 Change gears
Where change gears are provided, the number of teeth must be permanently marked on each of the change gears in such a location as to be legible with the change gears in place.
6.0 Sealing requirements
Note: The requirements of Part 1, section 5.0 apply, except subsection 5.2.
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.