[SINGAPORE] After more than four decades as Singapore’s sole propeller designer, manufacturer and repairer, Mencast Marine took the ambitious step to inject artificial intelligence (AI) and additive manufacturing into its operations.
This was a game changer for the company as it enabled faster production of its key product and required less manual labour.
Since it started in 1981, Mencast has been designing and manufacturing propellers for the tugboat and fast-boat market. The propellers are about 1 to 3 metres in diameter, and are made by melting bronze alloy ingots into sand moulds in a process known as sand casting.
The company also provides repair services for bigger propellers of up to 12 m in diameter, and gets orders for both production and repair from firms in Asean and even parts of Europe.
The business, however, does come with challenges. “We are very aware of the dependencies that we have in the supply chain,” Dr Chia Boon Tat, chief technology officer of Mencast Marine, told The Business Times.
For example, the company is highly reliant on raw materials such as sand and bronze alloy ingots that are imported from places such as Malaysia and Europe.
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Another issue has been the lack of qualified workers, as the labour-intensive production processes are very dependent on engineers.
“It’s very difficult to find new, young engineers who want to work in (this) type of environment,” said Dr Chia, adding that the company’s ageing workforce and its reliance on foreign labour have been a concern as well.
He also noticed that, in recent years, clients were looking for greener, more sustainable propellers – ones that contributed less to their carbon footprint through both the production process and in their operations.
Tech brings about a sea change
Given the challenges and changes in demand, the propeller manufacturer partnered Enterprise Singapore (EnterpriseSG) in 2023 to collaborate with the Agency for Science, Technology and Research (A*Star).
This involved two main projects to introduce AI, additive manufacturing and robotic automation to its production flow. “We believe that using these technologies will massively value-add and increase the productivity of (Mencast’s) operations,” said Dr Chia.
The majority of the production processes are carried out at the Precision Engineering Centre in A*Star’s Singapore Institute of Manufacturing Technology. This centre is part of EnterpriseSG’s Advanced Manufacturing Centre of Innovation.
The first project has helped to accelerate and improve efficiency in Mencast’s propeller design process.
Previously, designing propellers was more reliant on experts. Though there are software tools in place, much practical experience is needed as well as manual calculations, together with rounds of trial and error. Thus, it would typically take a few weeks to create around 20 versions of a design.
But, in the joint lab, AI-driven algorithms were implemented on top of Mencast’s existing parametric modelling and computational fluid dynamics tools, which already allow designers to refine their propeller models and analyse their predicted movements.
This has led to more than 10,000 design iterations being produced within a few days.
This vastly increases the number of possibilities, pointed out Dr Chia. Within a shorter period of time, Mencast can obtain a higher number of potential designs that are better in terms of performance, and also more sustainable.
The second project looked at producing propellers with additive manufacturing – or what many know as 3D printing.
Each design generates a toolpath for a robot arm to follow. As the arm, armed with a welding torch or laser wire, moves along the toolpath, it builds up a propeller with bronze alloy layer by layer.
While older models made from sand casting require around two weeks to a month to be completed, additive manufacturing has cut the time required for production by half.
Not only are the 3D-printed propellers more efficient to produce, but they are also 10 to 20 per cent faster than the older versions. For clients, this means a reduced carbon footprint as well.
Dr Chia is thus hoping for a “quantum jump in productivity” by leaning on AI and additive manufacturing.
The “silicon economy”
The partnership with EnterpriseSG and A*Star is part of Mencast’s foray into what it deems the “silicon economy”.
This means integrating more robotics, software and AI into all facets of its operations, explained Dr Chia.
It is a strategy that holds much potential.
Mencast can streamline its supply chain by mainly focusing on one type of feedstock – bronze alloy wires that are used in additive manufacturing. The company was already using these for its repair services.
“As we move into the silicon era, we are actually recruiting a lot of the younger generation (as well). They like these types of jobs because it’s higher technology,” noted Dr Chia.
This is not to say the current processes have done away with the need for engineers. Much of the post-processing – such as grinding down the freshly printed propellers – and quality control still require input from engineers.
Next, a lighthouse factory
The company is looking for ways to automate the manufacturing process even further.
As part of this, it is establishing a “lighthouse factory” – a curated space in its compound that is able to facilitate large-scale production.
Set to start production by the end of the year, it will employ Industry 4.0 technologies, including high-end additive manufacturing robots.
Mencast has started sourcing from original equipment manufacturers overseas to acquire its own manufacturing robots, which could bring down the cost by around two-thirds.
A few of these self-sourced robots have already been brought in, and are enabling manufacturing to scale up quickly, added Dr Chia. He aims to push the new 3D-printed propellers out in the second half of 2025, and also officially launch the lighthouse factory.
Once the factory is up and running, the technology will pave the way for Mencast to transform its business model by decentralising manufacturing and enabling it to expand globally.
The company hopes that, in the future, its tech capabilities can be transferred overseas so that its propellers can be manufactured in more countries. This would help it broaden its client base beyond South-east Asia and Europe.
The use of AI and additive manufacturing also sets the scene for Mencast to venture into producing higher-end propellers for bigger ships, such as supply vessels and high-end military vessels. In addition, the company would be able to offer its repair services to other industries too – such as the aerospace sector.
“We are trying to turn this into a network effect, rather than (be) just a manufacturing company,” noted Dr Chia.