The US Navy wants to start 3D printing parts for ageing naval ships. However, developing 3D models of these parts is a time-consuming process. GE Global Research, a division of GE focused on technology development, has therefore received $9 million from the US Office of Naval Research to develop a method to speed up this process.
Navy ships have a long lifespan; the average age of ships in the US Navy is 17 years. The oldest US Navy ship still in service today was launched in 1970. Keeping these types of ageing ships in service is quite a challenge, partly because many parts are no longer produced. These parts must therefore be custom-developed, which takes a long time.
Producing parts faster
The US Navy is therefore looking at additive manufacturing to produce replacement parts faster. This form of manufacturing allows parts to be produced in very small runs or even a run of one. Parts for older machines that this makes no longer interesting for manufacturers to produce via traditional manufacturing technologies can still be made as a result.
However, this requires 3D models. Redeveloping an existing part takes a long time. To speed up this process, GE Global Research, in collaboration with researchers from GE Aviation, GE Additive, Honeywell, Penn State, Lawrence Livermore National Laboratory, Navy Nuclear Lab and the National Center for Defense Manufacturing and Machining, is developing so-called 'digital twins'. These are living and 'learning' digital models of physical objects such as naval ship parts. The models are based on model-based data of the part and sensor-based data from 3D metal printers.
Single source of truth
The models are continuously updated so that the digital model is continuously an exact replica of its physical counterpart. Digital twins thus serve as a 'single source of truth' for all data related to the part. This includes information about the object's current state and performance, as well as the state the object was in at earlier points in its history and the performance it delivered then. This makes it possible, on the basis of a digital twin, to carry out analyses to detect signals that may point to impending problems, among other things.
So GE Global Research now wants to deploy these digital twins to create faster 3D-printable models of parts of naval ships, among others. This has been a considerable challenge so far, as such models have strict requirements. "The main challenge with industrial 3D printing is to additively build a part that contains exactly the same material composition and properties as the original part produced via subtractive methods. With the Navy's mission-critical equipment, there is no room for deviations in material performance or manufacturing errors," explains Ade Makinde, Principal Engineer Additive Technologies at GE Global Research.
From years to weeks
Using digital twins, GE Global Research not only expects to meet these requirements, but also to develop 3D models much faster than is currently possible. "With today's technology, designing a new part can take years. We think we can shorten this to weeks with the unique solutions now under development," Makinde said.
The project uses a technique for error-free printing that is being developed within the Accelerated Certification of Additively Manufactured Metals project at the Lawrence Livermore National Laboratory. This technique uses simulations to predict the end result of the printing process, so that problems in the design can be detected and rectified in advance of the printing process. Not only does this make prints less likely to fail, it can also help speed up the certification of 3D printed parts used for critical applications.
Parts for classic Porsche's
Additive manufacturing has long been used in other industries to produce parts in small runs. Porsche, for example, has been producing parts for classic Porsche cars using 3D printers since the beginning of this year. The car manufacturer previously produced these parts through traditional manufacturing methods, but could not efficiently produce them in small runs. As a result, the company struggled to keep low-demand parts in production. Additive manufacturing allows parts to be printed in smaller runs, making this possible.
Author: Wouter Hoeffnagel
Source: GE (pictured)
Source: Lawrence Livermore National Laboratory
Source: Porsche
