S-G-03–Specifications for the approval of type of gas metering devices–Part 21

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


Part 21: Flow conditioners

Table of contents


1.0 Scope

This part of the Specifications applies to flow conditioners used with certain meter types in natural gas custody transfer metering systems to improve the flow profile of a given piping installation.

2.0 Technical requirements

Note: The requirements of Part 1, subsection 3.1 apply.

2.1 Capability

The flow conditioner and piping configuration for each combination in 4.1.4 must demonstrate improvement in baseline conditions for the gas meter installed.

3.0 Marking requirements

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

  • 4.1 Permanency and legibility
  • 4.2
    • (a) Departmental approval number
    • (c) Model or type designation
  • 4.13 Verification marks

3.1 General

The following requirements apply:

  1. Markings required in Part 1, 4.2 (a) and (c) must be stamped on the edge of the flow conditioner flange, and be legible and visible when the conditioner is installed.
  2. The manufacturer's inspection marking (if other than the marking in a) must also be stamped on the top edge of the flow conditioner to attest to the conformance of the flow conditioner to the manufacturer's design and construction specifications.
  3. The pipe size and schedule of the upstream pipe that the flow conditioner is intended to be used with must be stamped on the downstream face of the plate or on the flange.
  4. Where the flow conditioner is not of a flange mounted type, the required markings must be stamped on the downstream face of the plate and on a nameplate/tag to allow for the identification of the model and its status with regards to the manufacturer's inspection carried out in accordance with design requirements, without disassembling the meter run.

4.0 Administrative requirements

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

  • 6.1.1(a) to (c)

4.1 Application for approval

4.1.1 Design

Along with the application for approval, the applicant must state the following flow conditioner design parameters with their tolerances.

  • Outside plate diameter (and outer flange where applicable);
  • Plate thickness;
  • Number of bore holes and their pattern;
  • Bore hole dimensions, as a function of the inside pipe diameter of the pipe in which the conditioner is intended to be used
4.1.2 Construction material

The applicant must provide a listing of the acceptable materials of which the flow conditioner may be constructed.

4.1.3 Test data
4.1.3.1 Third party test data from a recognized test facility

The applicant must submit test data from a test facility recognized by MC that demonstrates improvement in baseline conditions for specific the meter types or classes.

4.1.3.2 Standard

The test data supplied must conform to the latest version of the applicable AGA report for the type or class of meters the conditioner is intended to be used with. Where the applicable AGA report does not provide test data requirements for the approval of flow conditioners, the following requirements must apply:

  • Appendix D of AGA Report No. 3, Part 2 (Fifth edition, 2016); or
  • Test data conforming to the requirements as set out by another industry-recognized authority, subject to the following conditions:
    • Identification of the industry-recognized authority and the requirements document;
    • Provision of the flow conditioner approval requirements document to MC, where requested;
    • MC approval of the use of the approval requirement document for the submission of test data.
4.1.3.3 Combinations of flow conditioner model and meter type or class

The applicant must supply test data for each combination of flow conditioner model and meter type or class for which approval is being sought. This test data must be supplied for the Qmin and Qmax flow rates for each meter type or class.

Note: Qmin for lowest capacity meter in the meter type or class and Qmax for the largest capacity meter in the meter type or class.

4.1.3.4 Test medium

The applicant must specify the test medium used to conduct testing (i.e. natural gas, air).

4.1.3.5 Flow range

The applicant must provide the flow range of the flow conditioner, if less than the range of the meters.

Note: Limitations in flow ranges are indicated in the notice of approval.

4.1.4 Configuration requirements

The manufacturer must supply the piping configuration requirements for each type of meter the flow conditioner is intended to be used with. Any limitations must be stated, such as the number of elbows or partially opened valves preceding the flow conditioner.

The piping configuration requirements must include the following information:

  • The distance between the meter and flow conditioner stated in the form of the number of pipe diameters;
  • The downstream meter tube requirements;
  • The distance between the flow conditioner and any elbows or valves upstream of it stated in the form of the number of pipe diameters.

Note: The notice of approval will contain photos and diagrams of the flow conditioner models and piping configurations for each type of meter the flow conditioner is approved for use with.

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