Collett delivers 160 tonne valves to hydropower station

By Niamh Marriott15 September 2023

UK-based heavy transport specialists Collett & Sons has delivered two 160 tonne inlet valves to Dinorwig hydropower Station in Wales as part of an essential upgrade scheme.

Collett completed swept path analysis (SPA) reports, lashing calculations and plans and stability calculations prior to the transport. (Photo: Collett and Sons)

Working on behalf of Rhenus Project Logistics, Collett has completed the first two deliveries of the project, a crucial milestone in the ongoing upgrade project, aimed at extending the power station’s operational lifespan for the decades ahead.

A total of six valves will be delivered to complete the project, with each valve weighing 160 tonnes and measuring 5.3 metres long, 4.7 metres wide and 3.7 metre high.

Pre planning

Prior to deliveries, preliminary works were completed by Collett’s project management and consulting departments. This included swept path analysis (SPA) reports, lashing calculations and plans, stability calculations, as well as a comprehensive test run and route studies.

Collett discharged both valves from the vessel using an 800 tonne mobile crane. (Photo: Collett and Sons)

During the test run, a load replicating the exact size and shape of the valves was constructed to ensure safe transportation.

The first two inlet valves arrived at the Port of Penrhyn, located East of Bangor, North Wales. Working under CPA contract lift conditions, Collett discharged both valves from the vessel using an 800 tonne mobile crane. Ensuring secure transport, each valve was carefully lashed onto two 10 axle modular trailers.

The journey from the port to Dinorwig station was 12 miles and took three hours to complete.

Permits and escorts

Throughout the transport, a comprehensive support system was in place, including full police escorts and Collett’s own escort vehicles. The loaded trailers were accompanied by three 8x4 ballasted tractor units, two primary and one in support. Special order BE16 permits were obtained by Collett’s Permit Team to facilitate the move.

The loaded trailers were accompanied by three 8x4 ballasted tractor units. (Photo: Collett and Sons)

Upon arrival at the power station, the two main inlet valves were directly transported to a designated storage area and lowered onto stools.

After later preparation, the valves were transported into the mountain and offloaded by overhead gantry cranes.

Dinorwig station, located near Llanberis in the Snowdonia National Park, is the largest pumped hydroelectric storage facility in the UK.

With a maximum power supply of 1,728MW and a storage capacity of approximately 10GWh, the station manages water between the Marchlyn Mawr reservoir and the Llyn Peris Lake to generate power as needed.

The cargo was transported under police escort. (Photo: Collett and Sons)
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