Cammell Laird and the RWE Pontoon
When iconic shipbuilder Cammell Laird required a structurally compromised pontoon to be removed from the River Mersey, the S Evans & Sons team worked around the tides to manage the complex assignment.
S Evans called on the support of specialist third parties as well as Carmet Tug’s workboat Vital and HAPO’s crane vessel, Lara 1, to deliver the programme, demonstrating the team’s ability to work offshore and in challenging conditions.
Before mobilisation, S Evans used Salvesen UK’s dive team to conduct underwater investigations to survey the current condition of each element of the floating pontoon. These details where used to assess the deconstruction sequence and working with offshore engineers Malin Group, our team supplied a comprehensive solution to our client. Assessments where also made of the river bed levels to ensure the proposed equipment could safely operate around tide levels.
To remove the pontoons from their anchorage, Vital was attached to each birthing pontoon under the guidance of offshore engineers Malin Group so that S. Evans’ team could hot-cut the chains and release the pontoon from the link bridge.
To remove the link bridges, Lara 1 was used to sling each section, lifting and transporting it to the quayside for processing. Once the section was slung, S Evans operatives used hot-cutting techniques to release the bearings. The sections were processed using cold cutting techniques. being processed into manageable sections and removed. Following the link bridge’s removal, Vital transported the inner birthing pontoons to the slipway for processing.
A Hitachi 870 excavator, connected to the pontoon’s chassis with chains, pulled the pontoon up the slipway and into the processing area, where it was broken into manageable sections. The concrete and polystyrene waste from the pontoon was separated and removed from the site for recycling.
Once all pontoons and link bridges had been removed, Vital was used to remove the chains and anchor blocks held in the water by buoys via grapple.
All works were carefully planned around tide times. Excavator works on the slipway were carried out during low tide, while Lara 1 was used during high tide only.