Introduction: External corrosion has been identified on auxiliary valves on the impulse rails to the governors. The external corrosion is due to condensation from pressure reduction, and galvanic corrosion due to dissimilar metals. There are a significant number of governors within SGN network operating at 2 to 7 Bar consisting of approximately 1600 Streams. Currently the governors must be bypassed or isolated at the fire valve to enable the valves on the impulse rails to be removed and replaced. This can often lead to a stream replacement or a full governor replacement.

Objectives:

• Complete and provide a detailed conceptual design to meet the performance criteria for the extraction of ball valves from Gas Distribution Governors.
• Complete a risk assessment and gap analysis of the conceptual design against relevant aspects of primary and secondary legislation, SGN and Gas Industry standards.
• Carry out a detailed design review, addressing design gaps identified.
• Manufacture prototype for use and carry out offsite testing against criteria specified.
• Following completion of the off-site testing, incorporate any design revisions as required to allow approval for live field trials or otherwise.
• Provide training package and training for operatives carrying out the valve replacements.
• Support the installation and track performance of at least 3 live field trials.
• Assess the performance from the trials and review the outcomes and provide recommendations
• Following the live trials, prepare installation and maintenance Work Instructions in SGNs Safety Management Framework (SMF) format.
• A detailed final report is required on completion of the project.

Expected Benefits: As this project focuses on a conceptual design and the manufacture of prototype, for offsite testing and live field trials, it is envisaged that this novel BVR, would lead to the following financial benefits:

• Reduction in costs for repairs due to not having to bypass the governors
• Prevention of having to isolate governors
• Reduction in costs of not having to fully replace the governors
• Reduction in costs relating to governor replacements in alternative locations