This case study delves into the transformative impact of Wire and Arc Additive Manufacturing (WAAM) on the marine industry. This sector has traditionally been slow to adopt 3D printing due to its reliance on large-scale, custom components. WAAM has emerged as a game-changer, enabling the efficient production of complex, large metal components like marine propellers without the high costs and long lead times associated with traditional manufacturing methods.
The study highlights a pioneering achievement in 2017 when Damen Shipyards Group successfully produced the world’s first WAAM-manufactured marine propeller in collaboration with several partners. This breakthrough demonstrated WAAM's potential to revolutionize the production of critical, complex marine components.
WAAM offers significant advantages, including up to 70% material savings, reduced lead times by up to 80%, and cost reductions of up to 40%. It also supports rapid prototyping and the creation of innovative designs that are difficult to achieve with conventional techniques. Despite challenges like oxygen contamination during welding, advancements in flexible welding enclosures and oxygen monitoring systems have made WAAM a viable, high-quality manufacturing option for the marine industry.
As the marine sector increasingly embraces WAAM, it is anticipated that by 2030, additive manufacturing could account for up to 10% of the global marine manufacturing market, driving efficiency, sustainability, and innovation in producing customised marine components.
The Evolution of Metal 3D Printing
The marine industry has traditionally been slow to embrace 3D printing technologies, primarily due to the sector's reliance on large-scale, custom components and the high costs associated with traditional manufacturing methods like casting and forging. However, recent advancements in Wire and Arc Additive Manufacturing (WAAM) are beginning to shift this trend. WAAM enables the production of complex, large-scale metal components, such as marine propellers, without expensive tooling and lengthy production times. This case study explores the application of WAAM in the marine industry, highlighting its potential to revolutionise manufacturing processes.
3D printing with metals involves using a targeted heat source, often controlled by a Computer Numerical Control (CNC) system, to melt or sinter metal alloys and build up complex three-dimensional shapes layer by layer. The metal material is typically supplied in wire or powder form and is fused by the heat source to create the final product. Various metal 3D printing techniques exist, with Direct Metal Laser Sintering (DMLS) and Electron Beam Melting (EBM) being popular for small, intricate parts. However, WAAM has emerged as the preferred method for more significant, more substantial components due to its ability to produce heavy-duty engineering parts efficiently.
The global 3D printing market for metal, which was valued at approximately $3.36 billion in 2022, is expected to grow at a compound annual growth rate (CAGR) of 23.6% from 2023 to 2030, reflecting the increasing adoption of technologies like WAAM in industries such as marine, aerospace, and automotive.
WAAM in the Marine Industry: A Game-Changer
WAAM has demonstrated tremendous potential in the marine industry by enabling the rapid, cost-effective production of significant, complex components. A landmark achievement occurred in 2017 when the Damen Shipyards Group, collaborating with partners RAMLAB, Promarin, Autodesk, and Bureau Veritas, successfully developed the world’s first WAAM-manufactured marine propeller. This propeller, designed for a Damen Stan Tug type 1606, was made from bronze, measured 1300 mm in diameter, and weighed 180 kg. The project showcased the ability of WAAM to produce significant, critical components with intricate geometries, paving the way for broader adoption in the marine sector.
The marine industry is projected to increasingly adopt WAAM technology, with expectations that by 2028, approximately 30% of significant marine components will be produced using additive manufacturing methods, driven by the demand for faster production times and cost efficiencies.
Advantages of WAAM in Manufacturing
The primary advantage of WAAM lies in its ability to reduce material waste and manufacturing costs significantly. In industries like aerospace, where components are often machined from solid billets or forgings, traditional methods can result in more than 50% of material waste. WAAM, by contrast, builds components layer by layer, minimising waste and offering material savings of up to 70%. This efficiency is particularly beneficial for producing significant components like marine propellers, where traditional manufacturing methods are time-consuming and costly.
According to recent studies, WAAM can reduce lead times by up to 80% compared to conventional manufacturing methods. Additionally, companies that have integrated WAAM into their production processes have reported up to 40% cost reductions, primarily due to material savings and reduced tooling requirements.
Additionally, WAAM enables rapid prototyping and production of parts with complex geometries that would be challenging or impossible to achieve using conventional techniques. This capability opens up new possibilities for innovative designs in the marine industry, where custom and particular components are often required.
Overcoming Challenges in WAAM: Oxygen Contamination
One of the significant challenges in WAAM, especially when working with reactive materials like titanium and stainless steel, is the risk of oxygen contamination. Exposure to oxygen during welding can lead to oxidation, reducing the final product's corrosion resistance and mechanical properties. To mitigate this risk, flexible enclosures have been developed to create an oxygen-free environment around the welding area.
These enclosures, such as those designed by Huntingdon Fusion Techniques Ltd, offer a cost-effective alternative to traditional vacuum systems. By purging the enclosure with inert gas, such as argon, the oxygen content can be reduced to levels as low as ten parts per million (ppm), critical for ensuring high-quality welding. Some enclosures are large enough to accommodate entire workpieces, welding equipment, and even robotic systems, making them ideal for large-scale marine applications.
Ensuring Quality: Oxygen Level Monitoring
Maintaining an optimal welding environment is crucial for ensuring the quality of WAAM-produced components. Advanced instruments like the PurgEye® Weld Purge Monitor® series, specifically designed for welding applications, can detect oxygen levels as low as ten ppm. These monitors provide real-time data, helping to maintain the oxygen-free conditions necessary to prevent discolouration and preserve the corrosion resistance of the final product.
Ensuring such low oxygen levels during the WAAM process has been shown to improve the mechanical properties of the final product by up to 15%, further enhancing the quality and durability of components produced for the marine industry.
Conclusion
WAAM presents a significant opportunity for the marine industry to achieve cost savings, material efficiency, and the ability to produce complex, custom components that are difficult or impossible to manufacture using traditional methods. The development of flexible enclosures and advanced oxygen monitoring systems, such as the PurgEye® 600, has further enhanced the viability of WAAM for processing even the most reactive materials without the risk of oxidation. As the marine industry continues to explore and adopt these technologies, WAAM is poised to play a pivotal role in the future of marine manufacturing.
By 2030, additive manufacturing, including WAAM, is anticipated to account for up to 10% of the global marine manufacturing market, driven by its ability to produce highly customised components efficiently and sustainably.
