3D printing has reached numerous industries across the globe over recent years, and now nuclear power plants can be added to that list. Just this week, Siemens completed the first successful installation of a 3D printed part inside of a nuclear power plant in Slovenia. The part, an impeller, is for a fire prevention pump that is constantly rotating and outputting pressure for the fire protection system. The breakthrough comes as quite an accomplishment, with the safety requirements of parts used in nuclear energy being held to an extremely high standard. The plant it was produced for, Krško Nuclear Power Plant (NEK), is one of the highest ranking European nuclear power plants, providing over a quarter of Slovenia’s power, as well as more than 15 percent of Croatia’s for the past 30 years.

Krško Nuclear Power Plant located in Slovenia.

The original impeller, measuring 108 mm in diameter, needed replacement after being in service for nearly 40 years. Because the original manufacturer of the part no longer exists, Siemens was contracted to produce a replacement part using reverse engineering. Without additive manufacturing, replicating the part with the high accuracy needed would have been near impossible. However, with 3D printing technology, the team of experts deployed by Siemens was able to create a replacement part of the utmost precision with ease.

According to the plant’s Head of Maintenance, Vinko Planinc, “The better than expected performance of this 3D printed part gave us confidence that we can reach the full life expectancy from our asset. Siemens has a long history of innovation in this area and their dedication to providing their customers with the latest, proven innovations made them an excellent partner for this project.”

The original impeller (left), the 3D printed prototype (center) & final resulting 3D printed replacement part (right)

The testing process for the 3D printed part was quite extensive as the quality control and safety requirements previously mentioned are very high. In-house testing was performed in collaboration between Siemens and operators at the plant while external testing was also performed by an institution that conducted CT scans and material testing. The test results revealed that the 3D printed part’s properties were actually stronger than the original impeller being replaced.

Siemens has made great efforts to enhance and grow its additive manufacturing department. In 2016, the company opened up an extremely high-tech additive manufacturing facility in Sweden that serves as home to many members of the Siemens team tasked with developing the replacement part.

In response to the successful installation on the 3D printed impeller, Tim Holt, CEO of Siemens Power Generation Services division, stated, “We continue to push forward our investments and cutting-edge advancements in additive manufacturing and 3D printing. This achievement at the Krško nuclear power plant is another example of how the digital transformation and the data-driven capabilities we have are impacting the energy industry in ways that really matter. Additive manufacturing’s reduced lead times and faster production optimizes parts replacement and creates real value for our customers.”

Siemens and the Krško nuclear power plant are continuing to work in collaboration to produce other replacement parts needed in the future with 3D printing technology.