Northern Gas Networks (NGN) engineers use schematics to quickly get an overview of asset locations and sequences when responding to incidents. Schematics are a simplified view of the gas distribution network similar to a London Underground Map.
Historically, at NGN, Schematics are printed on paper and manually created in a CAD system, using an old GIS data extract, for reference. Over time the CAD and GIS systems have become out of sync with data updates being applied in one system and not in the other.
This is causing an operational risk to NGN as field engineers are making decisions based on schematics, which are potentially missing key information. Also, there is no uniform design for schematics; they can vary across operational areas, making them difficult to understand if you’re not unfamiliar with a particular area.
Schematics are useful for planning and emergency response purposes. The generation of schematics has historically been done using manual CAD drawing tools and is an expensive and time-consuming process. As soon as the network data changes then the schematics become out of date and old versions continue to be used.
The use of old schematics creates risk to safety and reduces the efficiency of planning and maintenance, but it is prohibitively expensive to update the schematics by hand. The only viable long-term solution to schematic maintenance is to generate them automatically from the live network data.
Objectives
The project objectives are:
• Reduce operational risk by improving the currency of schematics (by generating them from live data)
• Ensuring schematics are uniform in design (and so support more consistent provision of information)
• Shortening the time to produce schematics and removing the risk of data errors being introduced to schematics (by removing the otherwise labour-intensive process)
Learnings
Outcomes
The main outputs of the project are the latest schematic PDFs produced by the process developed during this phase, a data improvement report, and a rule catalogue.
The scripts and tools used to build the process were not a deliverable as part of this phase and are retained by 1Spatial. NGN is currently undertaking a separate GIS upgrade project which will radically alter data structures and models, including those relating to schematic production, by moving to a Utility Network (UN).
The delivery of the UN will include a large amount of work required by any future schematics phases as documented during this phase, as the UN (like schematics) relies on the digitised asset data being of high quality and following defined sets of rules. After the GIS upgrade is complete there is an opportunity to look at the new system and its data and then detail any potential future schematics phases.
Lessons Learnt
· The methods used did not cause significant problems and the iterative approach produced better and better outputs as the project progressed through the fixed time available.
· This phase demonstrated that the methods were viable, but more work would be required around the spacing and placement of assets and their labels to ensure maximum readability to move this process to higher TRLs.
· As the methods rely on digitised asset data and remove manual intervention, they highlight quality issues with the data. Low quality data in the source system requires correction there, rather than applying a correction in CAD when a schematic is manually produced by a user.
