Traditionally, bevel gears are produced as blanks from which the teeth shape is cut. This generates a great deal of material waste. The EcoGear project, a joint R&D venture of Oerlikon Balzers, Stockholm’s KTH Royal Institute of Technology, and industry partners Scania, Georg Fischer and Buderus Steel, was launched in 2020 to develop an alternative to replace the traditional manufacturing process.
“The goal of the EcoGear project is to develop a pre-forged blank at the beginning of the process chain with a near net shape geometry of the teeth,” says Tony Ulander, Oerlikon Balzers’ Sales Manager for Scandinavia. “This dramatically reduces the machining effort to achieve the desired shape and the material waste; it also increases tool lifetime.”
However, this new approach raises challenges for the entire process chain, including the tools and coatings. Oerlikon’s role in the project includes establishing the parameters for the cutting data and the criteria for running operations. “By utilizing primeGear, we can optimize surfaces and edges with pre- and post-treatments together with coating. This makes it possible to increase tool life by up to 80%,” says Kristofer Malmberg, Oerlikon Balzers’ Tribology Specialist. “Cutting data collected over the course of the project gives us the documentation needed understand tool wear and to optimize the tool surface and edges.”
The team found that the EcoGear solution reduced not only material waste, but also the volume of energy and resources needed for production, machining, transport and recycling. Results of a pre-study announced by the team notes: “The potential material savings are estimated to be up to 20% of total weight of the workpiece. If the workpiece weighs 37.8 kg and 80,000 bevel gears are produced per year, this would lead to material savings of approximately 600 t steel per year. The volume of chips generated in gear milling in a year would be reduced from approximately 700 t to 100 t.”
