Maintaining an efficient and cost-effective supply chain doesn’t end once the product is produced. The manner in which parts and products are repaired (if at all), how often parts are replaced and the overall maintenance process has a big influence on a company’s bottom line. Additive manufacturing allows for keeping virtual inventory and manufacturing spare parts only when needed which can contribute greatly to cost savings. Another important factor in this equation is addressing issues of wear and tear. As always, our #AMapplication series focuses on AM applications that are in use today, this installment is dedicated specifically to those applications used for maintenance and repair purposes.
Now and 30 Years from Now
One of the advantages of AM is creating a holistic end-to-end solution. When we discuss end-to-end we usually refer to the entire supply chain from placing an order through manufacturing ending with delivery to the end customer. But what happens after regular use? Let’s say 30 years from now when a part breaks down? A truly end-to-end solution goes all the way down the line. For example, just recently Siemens Mobility was asked to build 13 (in addition to the existing 16) high-speed trains for the Russian railway company, RZD. The agreement doesn’t end with supplying the trains, it includes an agreement to maintain and service the trains for the next 30 years, using AM of course. In order to do so, 2 Stratasys machines (Fortus 450mc) have been installed in their facilities in St. Petersburg and Moscow, which will additively manufacture rail replacement parts on-demand. Lufthansa, as well, has been using AM for the production of aircraft parts and for MRO purposes. The Maintenance, Repair and Overhaul (MRO) division of Lufthansa has an additive manufacturing center in Germany for repairs, spare parts, and tools.


Same Technology Different Method
The same AM build process which basically deposits layer on top of layer is also utilized for repair purposes. The AM layers are deposited on an existing part or product, adding material and reforming damaged areas. AFI KLM E&M (Air France Industries and KLM Engineering & Maintenance) is one example where AM laser-cladding is used for repairs. In fact, Optomec recently released a white paper showing how laser cladding repairs used for gas turbine engines can potentially improve return on investment (ROI) by 184% compared to traditional processes. In a similar manner, EOS provides a repair service for tool inserts, Trumpf uses laser metal deposition for repairs (up top as presented last year at Formnext), and Caterpillar Inc. uses AM to produce and repair solar turbines components in-house (below). Another AM repair method currently used for repairs is cold-spray. At Avio Aero, the method, based on tiny metal particles that are deposited filling the areas affected by wear and tear, is used for the GE90 engine.

The Tools for the Job
If possible, it’s better to avoid maintenance altogether. In a previous #AMapplications post we showed how AM can be used to design parts to withstand harsh conditions with little to no maintenance, but AM can also be used to make maintenance a more efficient process. “Companies tend to have one massive jig, no matter how big or small the repair area is, it’s just not very efficient. This is a solution that allows people to be much more flexible and just focus on the repair that they actually need to do,” says Tony Flanagan, Business Development Manager at FDM Digital where they developed an additively manufactured tool kit for repairing carbon fiber aircraft wings (above). The kit incorporates 4 extensions to a heat blower which enables directing heat only to the area needed, improving repair quality and precision. Another example is McLaren’s Speedtail – it comes with a built-in additively manufactured titanium toolkit (below), which is a lightweight solution, in line with the aerodynamical requirements of the car.
Between Repairs – The Emergency Spare Part
When a part needs to be repaired or replaced, a lack of an immediate replacement can cost thousands of dollars per minute, to be exact, in the automotive industry downtime can cost 22,000 dollars per minute. So whether a new part is ordered or sent for repairs a quick solution is needed to get the production line up and running. An additively manufactured spare part can be manufactured on-demand, and it doesn’t need to fulfill the needs of the original part, just keep things going until the new part arrives. Philips Lighting (now Signify) worked with Materialise to address such a problem. A bracket in their production line was prone to break and they required fast replacement parts. In the development process of the AM replacement part, they actually managed to create an improved part (below). While the original broke on a weekly basis, the first new AM replacement part installed lasted over 3 months.
The strength of AM is creating a smooth supply chain, it can address various maintenance needs across production and life span of a part. It works best as a holistic solution yet each one of these needs and phases can be implemented individually to improve production, overall maintenance, and the bottom line.
We’re always open to new applications – tell us about the AM applications you encountered, we’ll try to feature them here and follow us for more #AMapplications. For more insights and information follow us on LinkedIn or subscribe to our newsletter for weekly updates.
I liked the idea that an additively manufactured spare part doesn’t always need to fulfill the needs of the original part, just keep things going until the new part arrives, but would like to know how it is done. Does it change just the weakest link?