Following a routine propeller polish on British Royal Navy Type 23 Frigate HMS Lancaster, carried out by one of UMC underwater maintenance teams at HMNB Portsmouth, the survey report uncovered another area where UMC’s repair expertise came to the fore.
The underwater survey photography revealed cracks to the port propeller blade. Having worked closely with the RN for many years, UMC Design and Consultancy Division had previously written procedures for the removal and replacement of Type 23 Frigate propellers, and so was more than competent and able to remove the damaged propeller so that repairs to the blade could be completed in a dry environment.
UMC’s marine engineers and divers began their removal procedure by first recovering the cone to the surface using the dockside crane.
Using chainblocks attached to the hull brackets, the propeller was then lifted clear of the water. In order to ensure that the propeller did not rotate, it was kept at an elevation that ensured that the shaft key remained in the keyway.
The propeller was then laid on a flatbed trailer and transported to the dry dock for repairs.
UMC’s Design and Consultancy division provides project management services and turnkey solutions for the afloat inspection repair replacement and installation of a wide range of underwater hull and platform mounted marine equipment including: stabilisers, rudders, propellers, thrusters, stern seals, ICCP anodes and reference cells, hull plate and transducers fitted to commercial, naval and offshore vessels and platforms.
