Currently there are 559 sites with ERS modules that were originally designed by British Gas Research centre in the early 1980’s installed across SGN which are no longer supported by the original manufacture, and these are having to be replaced due to many assorted reasons. This can include obsolescence, the obtainability of spares, the soft spare parts are still produced but there is no support for the internal hard parts and the issues relating to the existing ERS module regulator configuration outdated and the general condition of the ERS Modules where a number are suffering from water ingress issues.
Following on from the ERS Module Regulator Conversion Phase 2 Project SGN_0133 it is now necessary to progress the Project to a Phase 2 which will involve the installation of new axial flow valves and assess its suitability on the gas networks at 3 sites, 2 in the South and 1 in Scotland, which will meet existing industry specifications. This will enable the ERS modules to be upgraded, overcoming issues such as obsolescence which will be impacted on during GD/2, obtainability of spares, prolonging the existing vessels asset life, reduce the need to replace the vessels and reduce environmental impact. Current inspection methods require extensive excavation works to dig out the pipe, remove the sleeve and visually inspect it, which are often costly, time-consuming and a resource burden on the GDNs. In June 2003 Advantica Report R6196 was produced which provided a risk assessment methodology for OLI4 pipelines contained within Air-Filled Sleeves. This report made a number of recommendations as to how potentially make a desktop assessment to select which pipelines should be exposed and inspected. Since this time sleeves have undergone a limited number of condition assessment since this was published and recommended as the overall cost is extremely prohibitive.

Benefits

SGN currently has over 559 ERS module regulators where these are no longer supported by the original manufacture and are being replaced due to many assorted reasons such as obsolescence, the obtainability of spares and the general condition of the ERS module regulators.
The replacement of these units requires the ERS module regulators to be replaced or relocated above ground, leading to a complete new site requiring large excavations, backfilling and infrastructure changes.