UK-based heavy haulier Collett & Sons has delivered two redundant 147-tonne main inlet valves (MIV) from Dinorwig hydropower station to a specialised facility in Bangor.
The deliveries are part of the ongoing upgrade scheme at the power station, with Collett having previously delivered two new MIVs earlier this year to replace existing equipment.
Operating within the mountain, each valve was loaded from the temporary storage area using an overhead gantry crane. The MIVs were securely loaded onto two 10-axle flat-top trailers. Upon exiting the facility, Collett was challenged with the long exit tunnel, featuring a demanding 10 percent gradient. To overcome this, Collett implemented a double-headed approach utilising two 8 x 4 heavy tractor units to pull the valves up the tunnel.
The valves were transported in convoy along the 11-mile (17.7 km) route to the specialist facility in Bangor. The convoy was accompanied by a police escort, as well as Collett’s abnormal load escort fleet.
Before transportation, Collett’s projects department conducted thorough preliminary works, including a comprehensive route survey, lift plans, method statements and risk assessment report. Additionally, Collett’s heavy lift team had previously attended the site, setting up the JS-125 500-tonne capacity jack-up system.
Upon arrival at the specialist facility, each trailer was reversed under the lifting gantry, and the MIVs were offloaded directly from the trailer.
