THE PROBLEM
Baymarine were contacted by a client to provide a solution for a series of corroded pipes used to move compressed air through a void space and to the delivery boxes located at the stern, feeding compressed air into the water around the Azipod propulsion units. The pipework had corroded over time, resulting in multiple leaks of compressed air into the void space, and a reduced flow rate into the water and therefore leading to increased vibration and reduced efficiency of the propellers.
THE SOLUTION
The preferred repair that was chosen was to replace the majority of the pipework with bespoke, prefabricated, high-strength flexible hoses connected to prefabricated carbon steel tee pieces and manifolds which were hot-dip galvanised for improved corrosion protection. As well as providing a long-term solution to the problem, this was also cost-effective.As the pipework connected to ship-side stub pieces, the solution required Class-approval and be rated for water-ingress prevention.
The existing, corroded pipework was removed while the steel pipe spools were fabricated by Baymarine in the workshop and a local supplier was engaged for the fabrication of the flexible hoses.
The pipes were then installed on board over a period of two weeks. Access was difficult due to the pipework being in a void space, and several transverse frame penetrations required cutting and sleeving to allow the flexible hoses to pass through.
The final result was highly effective, with the compressors capable of delivering full flowrate of compressed air to the propellers without compromising the void space structural elements and reducing the risk of further corrosion.
