Specialists from United Engine Corporation (UEC, JSC “ODK”) started the implementation of an innovative technology in aircraft engine manufacturing—rotary friction welding. This was announced by Almaz Miniakhmetov, senior engineer at the Research Institute of Engine Manufacturing Technology and Production Organization (NIID).
This innovation represents an important step in domestic aircraft engine manufacturing: for the first time in Russia, equipment has been implemented that enables the joining of superalloy components with diameters reaching up to 400 mm. The installation was built in strict accordance with the technical specifications established by NIID.
Friction welding technology has emerged as a crucial component in the manufacturing of the high-pressure compressor rotor for the advanced PD-35 engine. Under the rigorous standards for strength, precision, and dependability, this solution presents new opportunities for enhancing operational efficiency and decreasing component weight.
What Is Rotary Friction Welding and Its Significance
Friction welding is a technique for joining metal components through mechanical friction and applied pressure, producing heat adequate for plastic deformation and bonding of the materials. Unlike conventional arc or gas welding, no heating of the metal takes place. Instead, materials are joined through a solid-state process, substantially minimizing the likelihood of defects and microstructural damage in advanced alloys.
In the new installation, components are assembled under high compressive force and rapid rotation, establishing a bond free of gaps, cavities, or metal deterioration. This guarantees optimal joint uniformity, enhanced strength, and minimal residual internal tension.
Such technology is widely used in the aerospace sectors of the United States, Japan, and Europe. There, rotary friction welding is used in the production of rotor shafts, compressor components, and other essential aircraft engine parts. The rationale is straightforward: heavily laden engine components demand flawless joints with superior resistance to fatigue stresses, a requirement that friction welding consistently fulfills.
For Russia, the creation of domestically manufactured equipment of this class represents an important development. Historically, essential technological advancements in aircraft engine manufacturing have relied on imported equipment or foreign expertise. The new installation, engineered in accordance with NIID standards, addresses a vital technological deficiency and substantially enhances the autonomy of PD-35 production.
Benefits of Completed Structures
According to the press service of Rostec, completed structures produced through friction welding are lighter, with connections that are stronger and more dependable than those created by conventional techniques.
Reduced structural weight directly impacts the total mass and fuel efficiency of the engine. In the field of aviation, even minor reductions in weight result in significant enhancements in fuel efficiency and greater payload capacity. Simultaneously, more robust joints extend service life, lower operating costs, and improve reliability in demanding operating environments.
Furthermore, friction welding markedly decreased production waste, as slag formation and thermal defects commonly associated with traditional welding are essentially eliminated. This is significant not only in terms of cost but also for enhancing the sustainability and efficacy of manufacturing processes.
The PD-35 Engine: An Innovative Advancement in Wide-Body Aviation
The PD-35 is an advanced high-bypass turbofan engine with a thrust exceeding 35 tons, engineered for installation on wide-body commercial aircraft. It is regarded as the most powerful engine ever engineered in Russia, featuring a fan diameter exceeding three meters and capable of producing thrust comparable to the world’s foremost foreign engines.
The development of the PD-35 commenced in 2017. By late 2025 and early 2026, the prototype engine effectively completed the initial phase of bench testing at an open test facility in the Perm region. During over 50 test iterations, the engine was repeatedly operated at takeoff power, consistently demonstrating thrust exceeding 35 tons — a noteworthy accomplishment for the domestic aerospace sector.
Emerging Technologies and Advances in Manufacturing
Beyond rotary friction welding, the PD-35 program actively integrates additive manufacturing, composite materials, and digital modeling technologies. These techniques facilitate the optimization of intricate components such as compressor and turbine blades, minimizing weight while enhancing aerodynamic efficiency.
Composite fan blades, for instance, can decrease component weight by several hundred kilograms relative to conventional metal designs, thereby substantially enhancing specific thrust and fuel efficiency.
The development process also extensively depends on CAD/CAE modeling and topological optimization, which expedite design cycles and minimize the need for costly engineering iterations.
The International Framework of Aircraft Engine Advancement
An additional significant aspect is the competition within the global engine industry. Aircraft within the 35-ton thrust class are conventionally equipped with engines manufactured by Rolls-Royce, GE Aviation, and Pratt & Whitney. The Rolls-Royce Trent family, for instance, encompasses variants with performance attributes comparable to the PD-35, supported by decades of industrial and technological development.
For Russia, the development of a domestic engine in this category constitutes a crucial advancement toward decreasing reliance on imported power plants for wide-body aircraft—a particularly vital objective amid heightened sanctions and limited international technological collaboration.
Certification Obstacles and Future Outlook
Although the test-bench results are promising, the shift from demonstrator to mass production continues to be a complex process. According to experts, complete certification of the PD-35 as an operational powerplant may necessitate an additional two to three years or more, as comprehensive endurance testing and validation under extreme operating conditions remain to be conducted.
A crucial element in expediting this process will be the effective integration of technologies such as friction welding, additive manufacturing, and advanced composites into robust, repeatable production workflows appropriate for mass manufacturing. This necessitates close collaboration among engineers, research institutions, and industrial enterprises, along with continuous investment.
Conclusion: A New Phase in Domestic Aircraft Engine Production
The deployment of rotary friction welding equipment signifies considerably more than a mere enhancement of manufacturing instruments. It represents a wider shift within Russia’s aircraft engine sector toward establishing a self-reliant, comprehensive technological ecosystem capable of competing with leading global industry players.
The integration of cutting-edge manufacturing techniques, contemporary materials, and a well-established engineering culture establishes the basis for engines that can reliably perform under the most rigorous conditions. The PD-35 is establishing itself not only as a significant technical accomplishment but also as a technological platform whose innovations can be applied to future engine programs, thereby enhancing the technological independence of Russia’s aerospace industry on a global level.