High-speed applications require the tightest tolerances, minimal quantities of lubrication, low frictional torque, and high-purity roller bearing greases. In addition to the load caused by high speeds, the resulting increased heat development should also be taken into account. True running accuracy also plays a role with regard to a bearing’s service life. The Xspeed bearing equipment components were tailored specifically to this performance segment.
Service life and comparison tests with selected types on the performance test rig have shown that the actual service life of Xspeed bearings is up to 50% above the reference values for premium bearings. To achieve this, Findling specified the bearing clearance within a more narrow tolerance (CM) and adapted the dimensional tolerances of the connecting components and the radial runout accuracy to high speeds (P6).
The greasing is also designed for higher continuous temperatures, is high-purity and does not generate much noise. The high-performance grease used is designed for a temperature range of -50 °C to 150 °C. It is characterized by a very low start-up torque and an extremely fine particle structure. For bearings with C3 bearing clearance, Findling uses a high-purity, diurea-based high-temperature grease with an operating temperature of up to 180 °C. At 177 °C, this special grease still has a service life in accordance with ASTM D 3336 of over 750 hours. Because of its fine particle structure, this grease is also extremely quiet, but its higher base oil viscosity means that it has a higher start-up torque at lower temperatures and can be used up to -40 °C.
Particularly efficient double-lip 2RSDD seals with grooves on both sides have proven to be an optimum combination with special grease in the eXtreme series bearings. In the Xspeed bearings for high speeds, this type of seal also reduces the bearing’s internal heating such that performance can be increased even further. It was possible to reduce the internal heating by up to 10 °C compared to a standard RS seal, which directly affects the bearing’s service life. A non-contact seal variant (LLB) is also available for the Xspeed bearings. Findling uses a special production process for eXtreme and Supra series bearings. It does not involve the usual turning of seal grooves. Instead, they are produced using ceramic molds. This results in increased production precision and a significantly lower peak-to-valley height. The sealing lip thus slides within the groove, which ensures that the seal is also maintained at high speeds and drastically reduces frictional heat and wear.