To meet the needs of bearing and mechanical transmission professionals, the Cetim, a Carnot-labelled technology institute, has implemented a pooled test bed of rail bearings. Manufacturers can test innovative solutions and understand phenomena within high-burden mechanical components.
Impressive features: the bench allows to carry out tests on large bearings (boring: 160 mm, external diameter: 250 mm) and under heavy loads (up to 15,000 daN constant radial, up to ±5000 daN cycle in axial). For a constant radial effort, corresponding to the weight of the train, the axial efforts applied are cycle and correspond to phases of turning or misalignment of the track.
According to Ludovic Saunier, test engineer at NTN-SNR, "The difficulty of this type of equipment stems from the need for robustness in terms of the effort applied, the need for reproducibility and the need for axial effort cycling. The bench's steering system allows load and speed cycles to be programmed up to 1,600 rpm, and records effort, speeds, temperatures, vibrations, etc.. Funded from the collective action budget of the "Rolls" profession, this new pooled test bed provides the opportunity to conduct trials with great expertise and at a lower cost. "We do certification tests for rail bearings, but they are done on complex benches for several months," says Saunier. The characteristics of this type of test do not allow us to conduct the functional tests necessary to improve our knowledge of railway equipment in parallel." And that's the goal of Cetim's new test bed: to provide additional resources to industrialists in the service of innovation.