Improved reliability, profitability and reduced environmental impact
To meet the ever-growing performance requirements of high-speed precision applications, SKF has developed the new Super-precision Bearing Lubrication Unit for use with oil-air lubrication in high- speed applications. “This system can not only simplify new spindle designs but can also improve the performance of existing designs,” the company claims.
Advantages of oil-air lubrication The rotational speed at which a bearing reaches its operating temperature limit depends primarily on the heat generated in the bearing (frictional heat) and the amount of heat that can be transferred away from the bearing. One way to reduce frictional heat, particularly in bearings, is to be sure that the correct quantity of the appropriate lubricant reaches all necessary components. Many high speed applications can be lubricated with grease. However, as speeds and the resulting frictional heat increase, grease is typically replaced with an oil lubrication system. Very high-speed applications generally require a precise lubricant delivery system: the precise amount of oil required to adequately lubricate the bearing is continuously delivered by the oil-air lubrication system, thus minimising friction and operating temperature.
Oil-air lubrication system provides the following advantages:• Increases the bearing attainable speed • Reduces friction torque and energy consumption • Reduces environmental impact • Reduces lubricant consumption • Maximises the effectiveness of the lubricant • Positive pressure within the housing virtually eliminates the ingress of contaminants.
Improved performance and reliability As a result of SKF’s precise placement of the oil-air nozzle relative to the bearing, the cooling effect from the compressed air is optimised. This can stabilise operational preload within the bearing, further reduce frictional heat and maximise the effectiveness of the lubricant. The result: bearings can attain and even exceed their attainable speeds.
ApplicationsSKF Super-precision Bearing Lubrication Units can extend bearing service life and allow increased operating speeds for high speed applications such as machining centres, milling machines, internal grinding machines and spindles for printed circuit boards drilling. The unit works on high-speed spindles, with an air-oil lubrication system, in horizontal and vertical position.
