Avio Aero, a GE Aviation business that designs, builds and maintains aviation engines, will produce, at its Brindisi plant, the additive-manufactured components of the General Electric ATP (Advanced Turboprop) engine, for the General Aviation market. The additive manufacturing machines will be installed at the Brindisi facility from 2018 and the first production activities will start between the end of 2018 and the beginning of 2019.
The ATP, an all-European project led by the Centre of Excellence for engine development established in Italy, is the first turboprop to include 3D printed parts: 13 components, ranging from the combustion chamber to various structural elements, which have reduced the total number of parts in the engine by about 30%.
After Cameri (Novara), which specializes in additive manufacturing using the EBM (electron beam melting) technology, Brindisi is the second Avio Aero plant to adopt an additive process, although this time using DMLM (direct metal laser melting). The use of additive manufacturing has simplified the engine’s design, with fewer parts and solutions not feasible with conventional technologies, and also produced a lighter, more compact unit.
The Italian Government is considering additive manufacturing as one of the most important enabling technologies to address the aims and objectives pursued under the National Industry 4.0 Plan launched at the end of 2017. In fact, the Italian Ministry of Economic Development has undertaken actions to support Avio Aero’s initiative in Brindisi as part of a broader investment project proposed by Avio Aero that is being regarded as a significant contribution to the digital transformation of the manufacturing industry in Italy.
“Additive manufacturing is one of the enabling technologies in which Avio Aero is investing,” declared Riccardo Procacci, Avio Aero Chairman and CEO. “It’s now more than 10 years since we built the first prototypes, and today at Cameri – and soon also at Brindisi – we are using this technology to produce extremely innovative and, above all competitive, aviation engine components. Avio Aero is very proud of its achievements in this area. They would not have been possible without the priceless know-how developed by our engineers at Cameri, merged with the excellent reputation and commitment of our Brindisi employees. The fruitful network of partnerships Avio Aero constantly cultivates with the central and local Institutions, Universities and Research Centers has also been fundamental in creating the right conditions for this to come about.”
THE DMLM TECHNOLOGY
The laser sintering process, selective laser sintering (SLS), direct metal laser sintering (DMLS) or any other typical name is termed direct metal laser melting (DMLM) within GE. We believe this more accurately reflects the nature of the process since one typically achieves a fully developed, homogenous melt pool and fully dense bulk upon solidification. The nature of the rapid, localized heating and cooling of the melted material enables near-forged material properties when proper heat treating is applied. In the DMLM process, one typically stress-relieves the part(s) while still attached to the platform, followed by hot isostatic pressing (HIP), and a final solution heat treat. These addresses distortion, micro-cracking, and material properties, respectively.
ATP (ADVANCED TURBOPROP)
General Electric’s new 1,300 SHP-rated ATP (Advanced Turboprop) is the first entry in GE’s new family of turboprop engines aimed at Business and General Aviation aircraft in the 1,000-1,600 SHP range. Engineers in both Torino (Italy) and Prague, where GE placed the Turboprop Headquarter, spent more than five years working on a new engine design with power output hitting as high as 1,650 shaft horsepower that would enable GE to compete and win in large business & general aviation turboprops. The effort paid off in the fall of 2015 when Textron Aviation, the world’s largest maker of business propeller planes, announced it would use the new advanced turboprop engine (ATP) for its all-new, single engine turboprop—the Cessna Denali.
The ATP features an industry-best 16:1 overall pressure ratio (OPR), enabling the engine to achieve as much as 15% lower fuel burn and 10% higher cruise power compared to competitor offerings in the same size class with better time between overhaul (TBO) and class-leading performance retention. Some of the ATP’s advantages are credited to the industry-first technology designed into the engine.