An EU funded research initiative has identified a new process for joining lightweight materials in shipbuilding, which its inventors say, will make shipyards in Europe more competitive and environmentally friendly. It is currently standard practice in shipbuilding to apply welding techniques to joint lightweight materials such as aluminium. However, by moving to adhesive bonding methods, researchers believe that the cost of producing and operating ships can be significantly reduced, while also delivering environmental benefits.
The three-year BONDSHIP project resulted in detailed guidelines for the production, assembly, testing and repair of adhesive joints in shipbuilding. The 13 project partners carried out studies aimed at confirming their technique's potential for savings. These studies estimated that adhesive bonding of supports, stiffeners, and other attachments could provide cost savings of at least 20 per cent in the construction of large passenger ships compared with welding, and 25 to 30 per cent for large patrol craft. In fast passenger ferries, another benefit of adhesive bonding is an overall weight reduction of between 4.5 and 9 tonnes, which over a period of 20 years could save between 8,000 and 16,000 tonnes of diesel fuel.
It is expected that the environmental benefits may be substantial – estimates have been made that a medium sized shipyard produces about 60 tonnes per year of welding slag - considered a special waste for which a controlled disposal is required. The replacement of welding by adhesive bonding would remove this source of environmental pollution. Additionally, the widespread uptake of the practice would lead to an improvement in working conditions as it removes the need for many tedious and repetitive tasks associated with welding, such as filing and sanding, thereby minimising health hazards caused by airborne particles. Welding fumes and the potential fire hazard caused by welding heat would also be reduced.