SKF launched a revolutionary new seal that has been developed to save energy and cut maintenance requirements in high-speed passenger rail applications. Introduced to the market for the first time at InnoTrans 2016, the SKF Centrifugal Lip Seal features an innovative design that offers a unique combination of both contacting and non-contacting sealing on wheel set bearing units in one product.
The sophisticated seal allows for an optimized friction pattern throughout the operation cycle of high-speed trains. It incorporates a lip that is closed when the vehicle is travelling at low start and stop speeds to effectively exclude contamination from the bearing. When the speed is increased and the centrifugal force reaches a certain limit the lip opens and it becomes a zero friction seal, while the same centrifugal force prevents the ingress of pollution.
This intelligent two-seals-in-one design balances the trade-off between sealing function and friction torque, eliminating the need for a compromise on either. As a result, the unit can operate at a low temperature and extended maintenance intervals can be realized to cut the cost of servicing and improve the reliability of the application through cleaner grease. The significantly enhanced efficiency and energy savings can also lead to a reduction in the environmental impact of high speed rail.
“The SKF Centrifugal Lip Seal has been developed specifically to overcome the traditional sealing quandary manufacturers face with high-speed train wheel set bearing units,” Maurizio Martinetti, senior project manager at SKF product development, said. “No lip contact at low speeds meant there was a risk of contamination, while contact at high speeds led to energy-consuming friction and its other associated problems, such as excessive operating temperatures and the need for frequent maintenance. However, this new seal eliminates all of these issues for consistently efficient and high performance operation.”
