The Silent Series super-precision angular contact ball bearings have been developed in direct response to key issues faced by manufacturers of machine tool spindles. They identified that minimising noise and vibration levels during operation was key to improving confidence in the performance of their spindles. Bearing cages in lower-speed spindles can make rattling noises during rotation. This is normal, but can be mistaken for a sign that something is wrong with the spindle or its components. Rudolf Groissmayr, product line manager at SKF says: “The SKF Silent Series feature a new and innovative polyamide cage centred on the balls that minimises this ‘cage rattling’ during rotation. Their silent operation increases the confidence of the end-user in the quality of spindles.”