Now is the time to get on board with the latest bonding solutions
With some of the most discerning customers and apparently limitless budgets, the superyachts being built today can utilise the latest technologies and materials for every stage of their manufacturing process. This starts with the latest CAD packages and goes right through to innovative, high tech solutions for communications, entertainment, and the ultimate in luxury for interior design and décor. But there is one area where there is still a certain reluctance to make the leap to new and proven technologies and that is when it comes to joints and seals used across these unique vessels.
Since the earliest times, mankind has been tempted to set sail across the wide, open seas and these primitive vessels show mechanical methods of construction, using wooden pegs and tight bindings to hold the hulls together. The hulls of these vessels were then strengthened and their water resistance improved by the application of caulking, a process that may still be used today. But, now is the time for boat builders to think again and look at the benefits that can be achieved when using the latest bonding techniques over the more traditional mechanical fastening solutions.
The benefits of bonding
There are five key areas where bonding provides a significant benefit over the more traditional methods of drilling and tapping, soldering or welding a joint. These benefits apply whether the bonding approach is used in the initial construction phases but also when vessels are subject to refurbishment and upgrade. They are:
- Light weighting
Aesthetics – These amazing vessels are designed to impress; with sleek lines, shining surfaces and sumptuous elegance so why would you want to secure deck fittings with clumsy mechanical bolts and rivets which detract from the design and may also provide a trip hazard? The use of an appropriate bonding agent, that is not only robust enough to meet the physical demands, but is also both UV and weather resistant, immediately eliminates these problems. A similar argument of aesthetics can also be made for the internal fixtures and fittings, where the replacement of mechanical fittings with the appropriate bonding and sealing products can help deliver a far more elegant finish and any joints will be virtually invisible, (and easier to keep clean).
Engineering – Bonding a joint offers several engineering benefits over the more traditional welding or mechanical means of joining. With the latter, it goes without saying that creating a hole in a hull for a bolt or rivet obviously increases the chances of water ingress. With both welding or mechanical fixings, the inherent stresses generated within the vessel are likely to be focussed on local points within the structure, which may become a point of weakness. With an adhesive bond the entire joint area will be subject to uniform load distribution, making it far stronger. When it comes to securing disparate materials, adhesives are far better suited to securing a strong bond and compensating for variation in the varying physical properties of differing components. For example, the thermal elongations of diverse substrate materials could impact on the effectiveness and durability of either a welded, or mechanical ie a bolted or screwed, fixing. Other considerations are that of the mechanical joint’s resistance to vibration, which over time may result in a loosening of the joint or the possible degradation over time of a welded joint which may in due course exhibit signs of fatigue. A final consideration is that of a far better resistance to both humidity and salt corrosion is often found in bonded joints than in those secured with metal based mechanical fixings.
Environmental – There are several aspects to the environmental argument for the use of adhesives, bonding agents and sealants. Firstly, modern methods of production for these products are constantly evolving and in line with recent legislative changes the environmental impact of both the manufacturing processes, the individual components and the finished product are all closely regulated to ensure that environmental damage is kept to a minimum, if not entirely eradicated. When it comes to the boatyard where it is being used, improvements in storage and application techniques ensure that there is far less wastage and the materials are less harmful to the workforce.
Financial – Despite the big budgets, efficiency in the build process is still a key requisite for any boatyard. Welding solutions probably require the highest level of investment in terms of equipment and its relative lack of portability may present challenges during the build process. (Welding may also present a fire hazard if used on vessels that are nearing completion.) Mechanical fixings and the equipment required to install them are relatively cheap, portable and allow for far more flexibility in terms of ‘on-site assembly’. However, the latest bonding and sealants solutions can be applied using, hand held application ‘guns’, that can be easily moved around the entire vessel with little or no delay. So, whilst costs of the actual fixing may be comparable, there is significant opportunity for savings to be accrued both in terms of supplementary equipment and actual time and man-hours.
Light weighting – Shipbuilders, like car makers and the aerospace industry, are constantly striving to find ways of making their vessels lighter. Not only does a lighter vessel use less fuel, (thus also saving money) but it may also bring other benefits in terms of handling and safety. To achieve this reduction in weight, materials such as aluminium, fibre glass and carbon fibre may be used, all of which can be bonded rather than using mechanical fastenings, the use of which will only add to the finished weight of the yacht.
As materials, vessels and bonding solutions all continue to evolve and new processes are developed, the debate about the use of mechanical and welded joints versus bonding in superyacht construction will no doubt continue. As with most areas of development and technology there are occasions where it is obvious which is the right solution, but more often than not there are arguments for and against each approach which need to be considered, in light of the above criteria, before a final decision is made.
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For more information please visit: https://www.koe-chemie.de/en/
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