P-G-20—Procedure for the verification and reverification of Coriolis mass flow meters pursuant to the requirements of PS-G-20

Category: Gas
Issue date: 2023-01-25
Effective date: 2023-01-25
Revision number: N/A
Supersedes: N/A

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Table of Contents

• 1.0 Purpose
• 2.0 Scope
• 3.0 Definitions
• 4.0 References
• 5.0 Safety
  • 5.1 Measurement Canada's health and safety policy
  • 5.2 Contractor and third-party safety and security requirements
  • 5.3 Potential hazards
  • 5.4 Contractor's responsibilities
• 6.0 Standards and test equipment
  • 6.1 Working level standards
  • 6.2 Inspection and test equipment
• 7.0 Inspection worksheet
• 8.0 Assessment of conformity with administrative requirements
  • 8.1 Interrogation hardware and software
  • 8.2 Markings
  • 8.3 Software version
• 9.0 Assessment of conformity with technical requirements
  • 9.1 Meter construction and condition
  • 9.2 Transmitter's electronic display
  • 9.3 Transmitter output verification
  • 9.4 Zero stability
• 10.0 Assessment of conformity with metrological requirements
  • 10.1 General
  • 10.2 Pressure and temperature working level standards
  • 10.3 Test equipment set-up
  • 10.4 Meter configuration
  • 10.5 Performance testing
• 11.0 Sealing
• 12.0 Inspection certificate
• 13.0 Fees
• 14.0 Nonconformity and defect reporting

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1.0 Purpose

This procedure provides instructions for the verification and reverification of Coriolis mass flow meters pursuant to the requirements of provisional specification PS-G-20.

2.0 Scope

This procedure applies to Coriolis mass flow meters within the scope of PS-G-20 that are subject to 100% inspection for the purposes of verification and reverification at a test facility.

3.0 Definitions

Refer to PS-G-20 for definitions of terms that are relevant to this procedure.

4.0 References

• Electricity and Gas Inspection Regulations
• GEN-16—Conformance With Industry Safety and Security Requirements
• GEN-27—Policy on the Issuance of Inspection Certificates and the Recording of Test Results and Reverification Periods Required Under the Electricity and Gas Inspection Act
• PS-G-20—Provisional Specification for the Verification, Reverification, Installation and Use of Coriolis Mass Flow Meters

Refer to PS-G-20 for other reference documents that are relevant to this procedure.

5.0 Safety

5.1 Measurement Canada's health and safety policy

Inspectors must be aware of and fully conform to Measurement Canada's (MC) health and safety policy, including but not limited to the provisions relating to the following:

• Hazardous materials
• Inspections at gas meter shops
• Personal protective equipment (e.g. safety glasses, safety shoes)
• Workplace Hazardous Materials Information System

5.2 Contractor and third-party safety and security requirements

Subject to the policy established in bulletin GEN-16, inspectors must be aware of and conform to the contractor's and any third party's safety and security requirements that are applicable to the work site.

5.3 Potential hazards

Inspectors must be aware of the following potential hazards which may occur during transport to and from the work site and while at the work site:

• Asphyxiation
• Aircraft
• Debris from a compressed air jet
• Extreme environmental conditions
• Flammability
• Heavy equipment in operation or in motion
• High pressure
• Noise
• Overhead meter conveyors
• Stacked skids or pallets of meters
• Toxic and irritant gas

5.4 Contractor's responsibilities

The contractor must supply the required test facilities, test equipment and certified gas measuring apparatus required to perform the inspection in a safe, efficient and convenient manner.

6.0 Standards and test equipment

6.1 Working level standards

The following certified working-level standards are required:

• Pressure standard
• Temperature standard (if needed)

6.2 Inspection and test equipment

Subject to the type, construction and configuration of Coriolis mass flow meters to be inspected, the following equipment is required:

• Calculator
• Conventional verification seals
• Laptop computer with software applications authorized by MC for inspection purposes
• Natural gas at operational pressure
• Pressure hoses and fittings
• Reference meter ^{Footnote 1}
• Sealing tool
• Sealing wire
• Teflon^TM tape
• Verification marks (sticker type)
• Wrenches for pressure fittings

7.0 Inspection worksheet

1. Obtain the inspection worksheet referred to in this procedure from any MC regional office for electricity and gas.
2. Record the following information pertaining to the meter:
   • Owner's name
   • Contractor's name, if different from the owner's name

8.0 Assessment of conformity with administrative requirements

8.1 Interrogation hardware and software

1. Review the meter's notice of approval (NOA) and any associated modification acceptance letter (MAL), and determine if any interrogation hardware and/or software will be required to facilitate the inspection. If so, obtain it from the contractor.
2. If the interrogation hardware and/or software identified in the NOA is the sole means of accessing certain information required for inspection purposes and that information cannot be accessed, record this as a nonconformity on the inspection worksheet. If possible, determine if the root cause is the meter or the interrogation hardware and/or software.

8.2 Markings

1. Examine the meter and assess its conformity with the marking requirements of PS-G-20.
2. Record the required markings of the meter and any nonconformity with the requirements on the inspection worksheet.

8.3 Software version

1. Confirm that the meter's software version is identified as approved in the NOA.
2. Record the meter's software version on the inspection worksheet.
3. Record the conformance status on the inspection worksheet and details of any nonconformity to the requirements.

9.0 Assessment of conformity with technical requirements

9.1 Meter construction and condition

1. Visually examine the construction and condition of the meter and confirm that it conforms to the requirements of PS-G-20.
2. Record the conformance status on the inspection worksheet and details of any nonconformity to the requirements.

9.2 Transmitter's electronic display

1. Visually examine the transmitter's electronic display and confirm that it conforms to the requirements of its NOA.
2. If the transmitter provides for a segment test, perform this test and assess whether all segments are present and clearly readable.
3. Record the conformance status on the inspection worksheet and details of any nonconformity to the requirements.

9.3 Transmitter output verification

1. On the transmitter display interface, confirm and record the activated pulse/frequency output associated with a legal unit of measure (LUM) (e.g. Hz), and maximum output.
2. Check and record the system units (e.g. kg/s) for process measurement (e.g. mass flow rate).
3. Check and record the calibration factors through the transmitter display or interrogation software, if applicable.
4. Record each K-factor associated with a LUM (e.g. pulses/kg).
5. Confirm and record the flow direction on the transmitter display.
6. Confirm if low-flow cut-off (LFCO) parameter is applied and matches the values indicated on the nameplate of the sensor, if applicable.
7. Record the conformance status on the inspection worksheet and details of any nonconformity to the requirements.

9.4 Zero stability

1. Check the meter for meter zero stability under no flow conditions (i.e. flow at full rest).
2. Record the mass flow registered on the inspection worksheet and details of any nonconformity to the requirements of PS-G-20.

10.0 Assessment of conformity with metrological requirements

10.1 General

This assessment involves performance testing of the meter's accuracy, repeatability and weighted mean error.

10.2 Pressure and temperature working level standards

1. Ensure the pressure and/or temperature standards selected for testing of the flow meter have suitable measuring ranges, resolution and accuracy for the meter under test.
2. Ensure the selected standards have a valid calibration certificate.

10.3 Test equipment set-up

1. Ensure the meter under test was calibrated against working standards.
2. Ensure the meter under test correctly connects with the reference meter.
3. Ensure the temperature standard measures the flow temperature at test points after the reference meter and the meter under test positions.
4. Ensure the pressure standard measures the differential pressure at test points between the reference meter and the meter under test positions.
5. Ensure high-frequency pulses from the meter under test, and that the reference meter is registered by a microcomputer which also registers temperature and pulses.
6. Ensure the test system runs automatically.

10.4 Meter configuration

Confirm that the meter is configured in accordance with the requirements of PS-G-20.

10.5 Performance testing

1. Ensure that the suitable test medium^{Footnote 2} is used at flowing conditions expected for the meter's intended use.
2. Set the flow rate as per the test points prescribed in PS-G-20 and complete the performance test.
3. Record the corresponding transmitter output values from the meter under test and the reference meter on the inspection worksheet.
4. Calculate the relative error of the transmitter output values, and compare the error to the applicable maximum permissible error (MPE) specified in Table 1 of PS-G-20.
5. Perform a performance test and repeat two more consecutive performance tests for each test point specified in Table 1 of PS-G-20, as required for the repeatability test.
6. Calculate the repeatability error and compare the error to the requirements specified in subsection 9.3.3 of PS-G-20.
7. Calculate the weighted mean error and compare the error to the requirements specified in subsection 9.3.4 of PS-G-20.
8. Determine the overall conformance status of the Coriolis mass flow meter in relation to all specified requirements and record the conformance status on the inspection worksheet.

11.0 Sealing

Refer to PS-G-20 for the sealing requirements of conforming Coriolis mass flow meters.

12.0 Inspection certificate

Complete and issue an inspection certificate in accordance with the requirements of PS-G-20 and bulletin GEN-27.

13.0 Fees

Charge the applicable fees for the inspection of each Coriolis mass flow meter at a location other than the operational location, as established in Schedule 1, Part IV of the Electricity and Gas Inspection Regulations.

14.0 Nonconformity and defect reporting

Report details of any nonconformity or defects identified during the inspection to the regional gas specialist for review and follow-up.

Footnotes

Footnote 1

Reference meter with valid proof of certification issued by MC's Engineering and Laboratory Services Directorate or by an MC recognized test facility or laboratory in accordance with G-16.

Return to footnote 1 referrer

Footnote 2

The test medium will normally be natural gas; however, another suitable fluid that has been submitted to MC for review and acceptance may be used as a test medium.

Return to footnote 2 referrer