A 3D-printing revolution?

For many people in the marine sector 3-D printing is a very new technology that does not seem to have much application. However a couple of years ago Maersk Tankers seized on this new technology as a possible way to revolutionise their supply chain for ship spares. Markus Kuhn, the Purchasing Manager of Group Procurement Marine argues, “What happens when a critical engine part on a tanker breaks down? Dealing with equipment malfunctions is a daily challenge for the crew on board. And for the procurement team on the ground, the job is to get the parts on to the vessel as fast as possible. This involves a race, first to locate the required part, get it then it to the next port of call and then to charter a boat to make the delivery because due to their dangerous cargoes, tankers are usually forbidden from entering a main port area.”

The logistics are further complicated by the fact that tankers do not always stick to a schedule of ports. Kuhn explains, “Two thirds of our fleet is operating on the spot trade, so customers charter a vessel, not always knowing exactly where the cargo will be discharged. It could be anywhere from Venezuela to Houston. Getting spares to a ship can add up to a very costly and complex logistical operation, with a huge carbon footprint plus the time delays involved.”

Maersk decided to install a 3-D printer on a tanker to allow the crew to ‘print’ off parts that they need. However it appears that this experiment has been quietly shelved and a spokesperson for Maersk Tankers would not offer any update on the 3-D printer situation. Reports suggest that it has been decided to install 3-D printers on shore rather than on ships which could at least shorten delivery times for spares that could be printed and be ready waiting for a ship’s arrival.

3-D printers use laser beams to melt down a raw material, building up the product layer upon layer. In recent years the technology has developed to allow printing in both plastic and metal, resulting in a flood of interest from some of the world’s biggest companies which are using it to speed up the production of and create complex, lightweight parts at a fraction of the cost of machined or moulded parts. Martha Rehnberg, also from Group Procurement Marine, who was driving the project with students at Copenhagen Business School, believes 3D printing could revolutionise the supply chain. “Today you can print very complex parts you never imagined could be printed before. All you need is a computer friendly 3-D blueprint as the starting point and the printer does the rest.”

“It is not yet known how far the technology could be used on board, but even printing a few spare parts would have a major impact on supply chain costs. It can cost up to $5,000 just to get one part on board a vessel. 3D printing would eliminate the costs of warehousing and packing, airfreight to the port, customs clearance and chartering of the delivery craft.”

Boarding the train

Being a very new technology means there are many unknowns, including how to license products from suppliers. The Maersk plan was to team up with manufacturers to develop the technology in partnerships. Hans Mortensen who is the Senior Manager at MAN Diesel & Turbo which supplies engine parts to Maersk, was enthusiastic about the idea, “We see it as an opportunity to collaborate with Maersk on 3D printing. Either you hop on the train and start learning, or you stay behind and watch the train leave.”

Nils Søholt from MAN sees the use of 3-D printing as a clear advantage for fast prototype and the freedom of design as the prime source of benefit but is much less enthusiastic when it comes to using the technology in the production of the serial production of non-complex parts. “We do not see plastic parts as much more than visual prototyping in our products which is heavy duty large diesel machinery although we are looking with great interest in the development of 3-D printing in metal although as components get bigger the competitive advantage of the technology is vanishing due to the relatively slow production method of 3-D printing.”

The materials used for 3-D printing are another issue. Obviously around 90% of engine parts are made from metal, but the days of having 3-D printers on board that can work with metal could be some way off yet. “The technology is there, but it is a matter of cost,” says Rehnberg. “Today a printer capable of making parts in metal can cost around $1 million compared with the $25,000 or so for an industrial one printing in plastic.”

Other engine manufacturers appear to be taking the same cautious approach to 3-D printing. When approached both MTU and Wartsila said that they were not using the technology. However it is very likely that they are following the same route as MAN and keeping a watching brief on the technology.

The military are also looking into the possibilities of 3-D printing at sea. US Navy ships equipped with 3-D printers are using them to print off items such as oil caps and drain plugs and plan to expand the use of the printers. By using the printers in this way the stock of spares required on board can be reduced with obvious benefits. The British Royal Navy is experimenting with a similar application but there is also the possibility of using 3-D printers to produce complete craft.

Already a small unmanned drone aircraft made using a 3-D printer has flown from a navy ship in trials and because such drones are relatively inexpensive they can be expendable. The same type of concept can be used for unmanned mine clearance craft, both surface and underwater versions using more sophisticated 3-D printers. Rather than having to carry a stock of these cheap unmanned drones on board it would be possible for an onboard printer to produce them virtually on demand.

The U.S. Navy has been testing the use of 3D printers on its ships to produce custom drones outfitted for specialized missions on board the USS Essex. The project, being carried out by researchers at the Naval Postgraduate School, is investigating whether modern communications and fabrication technology can be combined to give sailors a new tool for whatever mission they are deployed on.

Digitised computer drawings of the required units are loaded into the printer. Once the printer has printed the parts the crew then follow the instructions for assembly, marrying the plastic parts with electronic components that are already on board. Those parts include the motors, radio, controller and a GPS unit and this allows the body of the drone to be designed according to specific requirements for each mission. As Maersk has found, once a ship leaves harbour, getting additional parts to that ship becomes difficult. In the case of the USS Essex the drone was used to fly over ships in support of anti-piracy work and there could also be an application for similar drones on board merchant vessels which are transiting danger areas.

Shoreside advances

On shore the use of 3-D printers in the maritime sector is expanding. Building ship models for conventional tank testing and also for checking the aerodynamics is saving considerable time and improving accuracy. A team at the Naval Surface Warfare Centre, at Carderock in the US has created a scale model of the hospital ship using 3D printing technology. The state-of-the-art 3D printer used, enabled Carderock to deliver large, complex models of ships, which can be assembled faster than manual construction with the printers operating unmanned for 24 hours a day. This model was used to test the wind flow on the ship to improve the safety of operating helicopters from the ship.

Other test tanks are using the same technology to replace the skilled craftsmen needed for model production in the past. The complex shape of modern propellers might be one area that exploits 3-D printing particularly as the industry moves slowly towards composite propellers. Marine engine manufacturers are also starting to use the technology to develop printed versions of the complex casting moulds used for producing the metal castings used in engine manufacture and the next step is likely to be for metal printers to produce the actual metal parts themselves thus removing the whole expensive casting process from the operation although metal printing currently tends to be restricted to certain materials.

3-D printing in suitable metals is the challenge for the printer manufacturers. Most current metal printers use a sintering process to produce complex parts but powerful laser melting is another option. Currently this tends to limit metal parts to aluminium or titanium whilst most engine parts require special steels so the application tends to be limited. With 3-D printing it is possible to produce accurate complex parts so reduced machining may be required and small batch numbers are possible.

Maersk Line, which covers the company’s container ships, is more concerned about the effects of 3-D printing on trade flows. Michael Storgaard of Maersk Line commented, “It is too early to predict the full, long term impact of 3-D print technology. A substantial unknown factor is whether the actual technological development and cost of materials is capable of outweighing the scale advantages of global production. Shipping costs usually represent a fraction of the total production costs.”

3-D printing is an industry still in its infancy. Because parts can be literally made on demand it has the potential to change the character of many spare part supply chains particularly in the maritime world where it that supply chain can be costly. It could reduce the requirement to hold expensive stocks of spares, it can it could allow a much greater flexibility in developing custom made parts rather than having standard designs and the size of components produced by 3-D printing could increase considerably. However implementation still seems to be a long way off and it seems that the maritime world is watching developments rather than taking a lead.