S-G-03–Specifications for the approval of type of gas meters, ancillary devices and associated measuring instruments

Category: Gas
Issue date:
Effective date:
Revision number: 1
Supersedes: LMB-EG-08 and S-G-03


Part 20: Flow conditioners used in gas measurement systems

Table of contents


1.0 Scope

This part of the Specifications applies to flow conditioners submitted for approval and used with certain meter types in natural gas custody transfer metering systems to improve performance or to allow for the reduction of the piping.

2.0 Metrological requirements

In addition to the applicable requirements of Part 1, section 7.0, the following shall apply.

2.1 The flow conditioner and piping configuration shall reduce pipeline disturbances resulting in a measurement system improvement of ½ maximum permissible error of the meter installed.

3.0 Marking requirements

In addition to the applicable requirements of Part 1, section 9.0, the following shall apply.

3.1 Markings required in Part 1, 9.1.3 (a) and (c) shall be stamped on the edge of the flow conditioner flange, and be legible and visible when the conditioner is installed.

3.2 The manufacturer's inspection marking (if other than the marking in 3.1) shall 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.

3.3 The pipe size and schedule of the upstream pipe that the flow conditioner is intended to be used with shall be stamped on the downstream face of the plate or on the flange.

3.4 Where the flow conditioner is not of a flange mounted type, the required markings shall 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

The applicable requirements of Part 1, section 11.0 shall apply unless otherwise stated in this section.

4.1 Application for approval

4.1.1 Design

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

  1. Outside plate diameter (and outer flange where applicable);
  2. Plate thickness;
  3. Number of bore holes and their pattern;
  4. 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 shall provide a listing of the acceptable materials of which the flow conditioner may be constructed.

4.1.3 Test data

4.1.3.1 The applicant shall submit test data, from a test facility recognized by MC, that demonstrates improvement in baseline conditions for specific the meter types.

4.1.3.2 Subject to 4.1.3.3, the test data supplied shall 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.

4.1.3.3 Where the applicable AGA report does not provide test data requirements for the approval of flow conditioners, the following test data requirements shall apply:

  1. Appendix 2-D of AGA Report No.3: Orifice Metering of Natural Gas and Other Related Hydrocarbon Fluids, Part 2: Specification and Installation Requirements, (Fourth edition, 2000); or
  2. Test data conforming to the requirements as set out by another industry-recognized authority, subject to the following:
    1. Identification of the industry-recognized authority and the requirements document;
    2. Provision of the flow conditioner approval requirements document to MC, where requested;
    3. MC approval of the use of the approval requirement document for the submission of test data.

4.1.3.4 The applicant shall supply:

  1. subject to 4.1.3.4(a)(i), test data for each combination of flow conditioner model and meter type or class for which approval is being sought;
    1. The test data shall be supplied for the Qmin and Qmax flow rates for each meter type or class for which approval is being sought (i.e. Qmin for lowest capacity meter in the meter type or class and Qmax for the largest capacity meter in the meter type or class).
  2. the flow range of the flow conditioner, if less than the range of the meter(s);
  3. the test medium used to conduct testing (natural gas/air).
4.1.4 Configuration

4.1.4.1 Subject to 4.1.4.2, the manufacturer shall supply the piping configuration requirements for each type of meter the flow conditioner is intended to be used with.

4.1.4.2 The piping configuration requirements shall include the following:

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

4.1.4.3 Any limitations shall be stated, such as the number of elbows or partially opened valves preceding the flow conditioner.

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