Structural maintenance is widely recognised by ship owners and operators as an integral part of repair and maintenance regimes for all vessels. Specifically, repairing fatigue cracks present on key structural areas , is vital to preserving asset integrity, seafarer safety and cargo, while also meeting regulatory and class requirements.
Age-old problem collides with new complexities
While the management and repair of vessel cracks is an age-old issue, the root cause(s) leading to their occurance remains unknown. Current thinking suggests that the development of cracks could be triggered by a combination of factors including vibration, fatigue, corrosion and extreme or repeated loads.
However, new challenges, such as an aging global fleet and a growing requirement to retrofit vessels to ensure compliance with the IMO’s decarbonisation strategy, is adding new stress points to vessels; increasing the proliferation of cracks. For example, installing a scrubber on a vessel to ensure compliance with the IMO’s global sulphur limit may add stress to a vessel’s existing structure; exposing previously undetected structural weaknesses as a result of different weight loads causing cracks in new and unusual areas. This, coupled with the array of existing causation factors, increases the pressure on ship owners to find a cost effective and time efficient crack repair solution.
Traditional crack repair methods
Gouging and rewelding or crop and renewal are how cracks are repaired on vessels. However, while effective, these approaches come with limitations, including considerable time and budget commitments to complete extensive steel renewal.
Notwithstanding their limitations, these repair techniques remain widespread due to a number of factors, such as ease of acceptance by class societies, a lack of appetite for change from conservative ship owners and the desire of yards to preserve significant income from steel renewal work.
Now is the time for change
The current economic fragility of the shipping industry and beyond, with overcapacity, weak freight rates and the financial shock of COVID-19, has increased the need for ship owners and operators to maintain the lowest possible OPEX costs.
At SPS Technology, we have a proven alternative to reinforce traditional gouging and rewelding or crop and renewal techniques, which is cost effective and time efficient. Structural composites, such as our Sandwich Plate System (SPS), have been used in the industry for decades and offer a permanent, class approved, cost competitive alternative that’s fast, non-disruptive and delivers improved strength when compared to conventional steel structures.
Despite the proven economic benefits, confidence building is one area where work is needed before the industry fully adopts proven crack repair technology, such as SPS. This confidence will support a move away from traditional vessel crack repair techniques, which despite their limitations, have the benefit of a long and successful track record. The support of class in making the transition away from traditional crack repair and prevention techniques is gaining momentum and is likely to spark off the embracing of structural composites from ship owners and operators, shipyards, and R&M contractors.
In addition, the backing of shipyards could help mitigate current capacity bottlenecks that have resulted from COVID-19 containment measures. With drydock periods for each vessel expected to be shortened, embracing composite solutions could ensure crack repairs are completed faster, keeping projects on schedule that remain cost competitive with conventional crop and renewal and gouging and rewelding repair techniques.
The economic payback of a change in mindset
As the shipping industry continues to face financial pressures, new environmental regulations and unforeseen circumstance, approaches once considered desirable may no longer be adequate for ship owners and operators navigating this new landscape. Therefore, now is the time for ship owners and operators to revaluate all areas of their business and embrace new yet mature technologies proven to deliver safe, efficient and environmentally sustainable solutions in order to well position themselves amid an uncertain future.