PMC are working for National Grid Gas Transmission Operations at Moffat Compressor Station to rectify safety issues on various valve vent and sealant lines around the station as Principal Contractor.

At Moffat Compressor Station there are eight valves with Ermeto fittings which require the vent and sealant lines changing. The replacement of these eight valves will enable asset health performance improvements to be realised and reduce operational issues across the Scottish compression fleet. 

The scope of works is to complete the replacement of the vent and sealant lines to comply with T/SPN/6 on the eight defective valves. Seven of the eight valves are buried and excavations will be required up to a depth of approximately three metres to facilitate replacement of the valve and sealant lines on these buried valves. The eighth is in an existing valve pit.

We are currently in the final phase of the works, being to complete final reinstatement of each previously excavated area including installation of new pipe supports and bases, sand boxes and the reinstatement of existing paving slab walkways. These works are planned for completion early in November.

PMC are co-ordinating the design element of the works with the customer and Mott MacDonald, providing temporary works management and operational management of the project and sub-contractors who are providing services for site mobilisation, general civil’s and concrete breakout.

PMC have deployed a team of technicians from Ambergate to complete the mechanical works for the replacement of the old vent and sealant lines and installation of the new.

There have been some minor setbacks to date in the early phase of the works whereby buried concrete bases were found during initial excavation works that needed break out and removal from the excavation footprints. This brought in additional design works for new bases for the bridle pipework associated with the valves. Extreme weather conditions have hindered the project slightly, with heavy rainfall and high winds experienced in the latter stages of the project during civils reinstatement works.