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Through Optimum Use and Innovation of Welding and Joining Technologies
Improving Global Quality of Life
advanced technological level as for steel fabrication due to lower priority in the past by fabrication and
welding systems manufacturers.
There is a great potential, in particular for aluminium ship structures for further improvement. Development
is carried out in close co-operation between shipyards, research institutes, fabricators of production
systems and welding supply companies. Suppliers offer technologies and systems for robotic welding of ship
structures. Off-line programming based on CAD data combined with a high degree of automatic generation
of the complete control programmes for welding is required to fully realise the capacity and potential of the
welding station.
The main objective for using sensors in robotic welding of aluminium ship construction, is the need for
localising the point where to start welding and then to follow the seam. There are remaining challenges and
problems, which have to be solved before the technology can be considered to be ready for implementation
in the production of aluminium constructions in shipyards. The future work will be focused on the off-line
programming. So far it has been focused mainly on the problems connected to accuracy. The strategy for
handling the huge amount of data for a complex hull section and the welding required is not clear and has
to be emphasised in future work.
Generally, the business drivers in the shipbuilding industry include reducing both the cost of producing new
ships and reducing the total ownership cost over the life of the ship.
9.8.7
Hot topics
Improved Joining Technologies for Ship Structures:
There is the need for continued improvement
and the application of “World-class” processes that increase efficiency, reduce rework, and shorten
construction time. Joining processes such as precision arc welding, friction stir welding, and
hybrid laser arc welding continue to be of high interest. Additionally, the shipyards have interest in
expanding the use of automation for large marine structures using smart adaptive welding systems.
Process Control:
Application of process control that will result in more standardised production
processes, improved accuracy control, and improved cost, quality, and schedule performance.
Interest areas include advanced measurement techniques, expanded use of statistical process
control, automated data storage, analysis, and transfer. Distortion prediction and accuracy
control are important subsets of this. Controlling weld distortion continues to be a challenge for
shipbuilders and the problem increases as lighter and lighter structures must be built. Technology
needs include improved modelling and simulation tools and the development and application of
workable manufacturing processes capable of controlling distortion during fabrication. EWI has field
demonstrated a novel automated technology, dubbed Transient Thermal Tensioning, for control of
buckling distortion on thin panels.
Joining Non-traditional Materials:
There is a need for increased performance (e.g. speed and
manoeuvrability) and this is driving the requirement to reduce ship weight. This results in the use
of non-traditional materials including non-metallic composites, high-strength steel, aluminium, and
titanium. There are needs for materials joining processes for these materials and processes to join
dissimilar combinations of these materials.
Advanced Non-Destructive Inspection Techniques:
Shipyards want to minimise the cost of
inspecting welds. New solutions include the implementation of advanced non-destructive inspection
technologies. These technologies include processes for improved inspection under lagging,
ultrasonic and digital radiographic inspection of welds, inspection of composite structures, and the
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Needs and challenges of major industry sectors for future applications
