3D metallic printing breathes new life into wind turbine gears

The additive manufacture of metals by direct laser deposition (DLD) will allow the rebuilding and repairing gears in wind turbine systems, ensuring mechanical properties equal to - or even superior to - those of the repaired components.

This capability arises from a challenge launched by SERMEC Group, a company in the field of precision metalworking, that develops maintenance solutions for the wind industry.

With the support of INEGI and the Faculty of Engineering of the University of Porto (FEUP), it mobilized to answer one of the sector's greatest challenges: increasing the useful life of wind turbine components, while maintaining comparatively high levels of quality and reliability, when compared to that of a new component.

"These are components prone to failure at various bearing locations, intermediate shafts and high-speed shafts, which result in costly maintenance interventions. High repair costs can reach hundreds of thousands of euros, and the time the equipment is inoperable is relevant”, explains Ricardo Cardoso, responsible for the project at INEGI.

To solve this problem, INEGI's team of specialists is developing an integrated repair process based on the 3D reconstruction of large case hardened gear teeth through laser processing of metallic powders.

In addition to the process, deposition strategies are being studied to combine different materials to create functional gradient materials, in order to ensure compatibility between successive layers and good adhesion between these and the substrate.

"This additive manufacturing process, which arises from laser coating technology with coaxial powder injection, offers significant advantages over conventional repair methods, which necessarily involve the manufacture of a new component", says João Cruz, responsible for the project at Sermec.

The 3D printing process should lead to a shorter lead time, given the need to re-manufacture the components, and reduce the repair cost, with the reduction of manufacturing operations and raw material acquisition. The reuse of damaged or worn gears also contributes to a more rational use of resources, following circular economy practices.

The project also includes the creation of a numerical model, as a complementary predictive tool to support parameter definition and process optimization, and the development of test protocols to validate repair quality and reliability.

The project "GEAR3D: 3D reconstruction of large gear teeth via direct laser deposition" is co-financed by the European Regional Development Fund (ERDF) through the Competitiveness and Internationalization Operational Program (POCI).