In high performance turbomachinery, the maximum bearing temperatures can be a crucial parameter. To increase the operational safety and performance, Miba developed the patent pending eddy groove technology.
Bearing Performance Improvement
Miba eddy groove bearings develop significantly lower maximum oil film and bearing metal temperatures than conventional bearings, especially at medium to high loads and sliding speeds. At high sliding speeds, eddy groove technology clearly outperforms CuCr base material and thereby pushes the limits of bearings and applications considerably. Experimental results obtained on the Miba engine bearing test bench demonstrate the performance of the technology. (Green = Eddy groove bearing; Red = Conventional bearing)
Physically, robust grooves of a certain shape, arranged in a certain pattern, are machined into a specific area of the bearing material. The grooves are optimized to disturb the laminar lubricant flow and thus create the cooling effect, by improving temperature exchange between cooler oil near the shaft and warmer oil near the bearing surface. Compared to an identical bearing without whirling grooves, key operating parameters such as oil consumption, frictional power and dynamic properties remain practically unchanged.
The reduced bearing temperatures, induced by eddy grooves, can be utilized to: