3D Printing For Shipbuilding and the Maritime Sector

Published on April 23, 2017

3D Printing For Shipbuilding and the Maritime Sector

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  • 3D printing has been used in shipbuilding on a relatively small scale
  • There is a lot of research being conducted in 3D printing for the maritime sector.
  • The first commercial end use parts for ships are being installed
  • 3D printing could be used to test models, critical parts, on board repair and new geometries.

Whereas we can see big advances in 3D printing in automotive and aerospace the shipbuilding and maritime industries have been laggards in implementing 3D printing. This is partially due to scale. Ships are very large and 3D printers often do not at this moment have the size to be able to produce many of the parts for ships. Models used for shipbuilding are also quite large. This means that a test model of a ship or a wave test model has also so far been comparatively expensive to produce. At precisely the moment when other industries were looking at commercializing 3D printing in end use parts the oil price took a significant hit. This had huge effects on shipbuilders producing craft for the oil and gas industries. This has knock on effects in competition and orders across the industry and lead to a reduction in R&D and staff. Due to the timing of this the shipbuilding industry is still very much “battening the hatches” rather than looking to invest to commercialize new technologies for their industry.

These factors have held back the large scale introduction of 3D printing in the shipbuilding industry. There are a number of interesting things happening at the moment however that point to growth in 3D printing of ships. The same considerations that make 3D printing valuable for automotive and aerospace: lower weight, fewer parts, less labor, less stock, lead time reduction and quicker iterations also do play a role in shipbuilding.

Casting  of Propellors

Investment casting and other casting processes are used at scale in shipbuilding. For complex critical parts investment casting processes are used to make propellors and other critical parts. Investment casting of large, sometimes 1m to 3m parts, is an expensive multi step process. As an alternative some parts builders for the maritime industry are looking to do this with casting 3D prints. Using Voxeljet 3D printing for example a mold or core can be 3D printed and then cast. This saves on time and money in the investment casting process. Since the parts are very large for 3D printing however, the print time and part cost of these propellors is very high. Propellors are very complex parts which have to be made to exacting precision. Many companies are therefore a bit careful when rushing into a new technology to manufacture them. 3D printing such propellors does however save on labor and costs per part so this is why many companies are exploring this option at the moment.

Direct Metal Printing of Parts

Direct Metal Laser Sintering (Powder Bed Fusion) and Directed Energy Deposition have also been explored to directly 3D print metal parts for ships. Some of the largest EOS, SLM Solutions, Renishaw, Concept Laser (GE) and Additive Industries DMLS printers however have build volumes of around 50 CM. In shipbuilding land this is not very large. It takes quite some time to dial in a new part and produce it with a well defined regularity. Shipbuilders themselves, most notably Hyundai, have invested in 3D printing processes and are trying to commercialize larger 3D printing technologies.

A technology that is capable of producing large scale parts is Directed Energy Deposition. This is a cousin of Electron Beam Welding and similar technologies. These technologies have been deployed widely in industry for many years. With Sciaky and Optomec machines one can make 1m to 5m parts. These then are finished by CNC and other processes to smooth them. This limits your design space when comparing the technology to DMLS but it does let one print lower cost parts. These types of technologies are being explored and commercialized for shipbuilding as we speak.

Part Repair 

Directed Energy Deposition can also be used to repair critical parts. A worn down part is brought in and new material is deposited on it. Some of this material is then removed and a rejuvenated part emerges from the machine. This can be done on machines that combine 3D printing with subtractive processes such as the Lumex Avance does. At the Port of Rotterdam a consortium looked at 3D printing marine spares and evaluated the possibilities for them. For shipping contractors these opportunities could be huge if they adopt a technology and can offer cost effective repairs.

Meanwhile the US Navy wishes to put metal 3D printers on board ships. This can let the Navy ships stay afloat longer and could improve their combat readiness throughout a conflict. The higher utilization of Navy ships and being able to repair while under sail is a huge opportunity for the Navy. There are however a lot of technical hurdles when trying to 3D print metal parts on board ships. Stabilizing the 3D printer and fire safety are just some of the things that come to mind.

Wave Models

3D printing has been used for prototypes in the maritime sector. An interesting application is to 3D print wave models for testing ships geometries. This could save considerably on lead times and cost of these one off parts.

Custom Parts for Yachts

In the Yacht and Super yacht industry 3D printing has made the most inroads. Super yachts are often completely one off. Apart from the technical parts everything on a ship can be custom designed and made. Often this is done with craftsmen whose skills let them make anything in wood for example. For certain parts however 3D printing plays a role. Metal coated plastic parts are low weight and can be used inside the ship’s interior. Cast parts or direct metal parts can be used for ornamentation throughout the ship.

Commercialization of Larger Scale Printers

Essentially in order to continue to grow in 3D printing the shipbuilding industry will have to invest itself in commercializing large scale manufacturing using 3D printing. In aviation and space the necessary investments for commercializing their parts are being heavily subsidized by the US and Chinese governments. The automotive industry can piggyback on these investments because they essentially can use the same processes and build volumes. In shipbuilding however we will need to see newer large scale 3D printers for the industry to really be able to use them well. This investment will have to be borne by the shipbuilding industry itself. Given the large scale nature of the parts needed we will expect shipbuilding to be slower to adopt 3D printing than other industries. There are however many interesting opportunities for companies to outperform their peers through using 3D printing in their workflow and in manufacturing.