Russia is increasing its use of industrial 3D printing in the production of the PD-14 turbofan engine, which is the powerplant designed for the MC-21-310 passenger aircraft. Complex engine components are being manufactured using additive manufacturing, which has the potential to reduce material consumption, reduce manufacturing cycles, and produce geometries that are challenging to achieve using traditional production methods.
The task is being conducted by specialists at ODK-Aviadvigatel, a subsidiary of the United Engine Corporation, within the Russian engine-building industry. The PD-14 has emerged as one of the most critical platforms for the integration of additive technologies into the production of serial aircraft engines.
The development is especially noteworthy due to the fact that the technology has progressed beyond laboratory experiments. Components manufactured thru additive manufacturing have been certified and are currently being installed on serial PD-14 engines that are participating in the MC-21-310 certification program.
A Complex Component Gets a New Manufacturing Method
The swirler in the combustion chamber of the PD-14 is one of the most notable examples.
The swirler is a small yet critical element. It assists in the regulation of the airflow that enters the combustion chamber and aids in the formation of the necessary air-fuel mixture. The accuracy of manufacturing is particularly critical due to the fact that the stability and efficiency of combustion are influenced by its geometry.
The metal-powder technology was used to develop the component for additive production. The necessary geometry can be generated layer by layer directly from a digital model, rather than manufacturing a conventional casting and subsequently conducting numerous machining operations.
This method is especially advantageous for aviation-engine components, as it enables designers to generate intricate shapes while simultaneously decreasing the quantity of material that must be eliminated.
From Conventional Production to 3D Printing
The PD-14 swirler was developed in Russia over a decade ago. In 2015, ODK-Aviadvigatel collaborated with specialists from the All-Russian Scientific Research Institute of Aviation Materials to develop a swirler that utilized additive technology.
It was the first Russian component to be incorporated into an aircraft engine that was manufactured using additive manufacturing.
The technology employed selective laser melting, which involves the selective melting of layers of metal particles by a laser in accordance with a digital model. After the first layer is finished, an additional layer of powder is applied, and the process continues until the component is fully formed.
The method exhibited a significant decrease in manufacturing time when contrasted with conventional investment casting. Earlier Russian development work suggested that the additive process could manufacture the component at a rate approximately ten times faster than conventional manufacturing.
The PD-14 was subsequently transformed into a significant testbed for industrial metal 3D printing as the technology advanced toward serial production.
Why the Swirler Is Important
The combustion chamber is one of the most demanding components of any gas turbine engine. To ensure stable combustion across a broad spectrum of operating conditions, fuel and air must be combined and burned in a controlled manner.
This underscores the significance of the swirler’s geometry.
The component generates the necessary swirling motion in the incoming airflow. This assists in the establishment of the requisite conditions for the efficient mixing and combustion of fuels. The aerodynamic efficacy can be influenced by even relatively minor deviations in geometry.
Engineers are granted more flexibility in the development of these components thru additive manufacturing. The digital model can incorporate complex contours, internal features, and optimized structures without necessitating the same number of manufacturing stages as conventional production.
This could result in a reduction in technological operations and the potential for improved consistency among components for the engine manufacturer.
Minimizing Material Waste and Weight
The potential to decrease the weight of components is another major benefit of additive manufacturing.
A relatively large metal blank or casting is often the starting point for traditional manufacturing. The material is subsequently removed through machining until the desired shape is achieved. In contrast, additive manufacturing employs a progressive addition of material to produce the component.
This has the potential to significantly reduce waste and enable engineers to consider lightweight structures that would be challenging to manufacture conventionally.
In aviation engines, weight is of paramount importance. The overall weight and efficacy of the propulsion system can be enhanced by reducing the mass of individual components.
Additionally, the necessity for intricate fabrication can be reduced, and the transition from a digital design to a physical component can be expedited thru industrial 3D printing.
Certification Is the Real Test
However, the production of a component on a 3D printer is only one aspect of the process for an aircraft engine.
The geometry, material properties, strength, and internal structure of a printed component must meet the rigorous aviation standards. This is especially crucial for components that operate within the hot section of an engine.
The manufacturing process therefore includes extensive inspection.
The dimensions of the finished component can be verified by comparing it to its digital model using three-dimensional scanning. In addition, material properties are assessed, and X-ray computed tomography can identify internal defects that may not be visible on the external surface.
Implementing this inspection regime is crucial to address challenges from additive manufacturing, like internal porosity and structural variations, caused by improper management of printing parameters.
The fact that PD-14 additive-manufactured components have progressed through certification represents an important step for the technology.
Beyond the PD-14
The program’s importance is not limited to the MC-21-310.
Russia is endeavoring to broaden the application of additive manufacturing in its aircraft-engine sector. Other engines, such as the PD-8 and PD-35, are also incorporating technologies developed through the PD-14 program.
The goal is not to entirely replace conventional manufacturing. Rather, additive production can be implemented in applications where its advantages are most pronounced, such as for components that are intricate, lightweight, or challenging to manufacture.
This hybrid approach may become more significant as Russian engine manufacturers transition to higher production volumes.
A New Manufacturing Layer for the MC-21
The PD-14 is another milestone in the progression of Russia’s civil aviation manufacturing program, as it incorporates 3D-printed components.
The potential is exemplified particularly well by the PD-14 swirler. A digital design can be used to directly produce a component with aerodynamic geometry that is crucial for combustion, resulting in reduced material waste and fewer conventional manufacturing operations.
Consequently, what originated as an experimental demonstration in 2015 has developed into a certified production technology. As Russia continues to develop the PD-14 and other domestic aircraft engines, industrial 3D printing may become a more prevalent component of the country’s engine manufacturing toolkit.