Generally, the seal bearing a greater role than the dust cover, and by rotating flexible and low-speed rotation restrictions. Designers select the right seal must consider the lubricant performance and delivery systems, and the desired operating conditions.

For roller bearings in use to withstand high loads, strong impact, as well as water and rust debris intrusion, NSK company developed a new ultra-high load capacity of the sealed type, clean lubricating roller bearings. It is said that 34% of the load bearing capacity can be increased, with higher reliability, can work long hours under harsh lubrication conditions. Its improved performance sealed bearings, the integration of mechanics optimization design, new materials and seals patented technology, and easy to operate the installation.

In the conventional sealed roller bearing, the primary seal and width limits the length of the roller, which limits the load capacity of the bearing. Therefore, they are new roller bearing design, the retainer edge profile contains voids in the sealing member, the roller can be longer, such that increasing the diameter of the cage and roller lengthened, but does not increase the length of the cage, to achieve increased 34 % of basic rated load capacity, equivalent to 27 times prolong bearing life. The selection of high-quality bearing "TF" bearing steel, is also crucial to improve bearing performance, because the material impurities and uneven lubrication is the main cause of premature bearing failure.

Experience has shown that pollution in the working conditions, easy to enter the bearing debris, which will damage the grain raceway debris, causing stress concentration. In addition, if lubrication is uneven, hard contact of the metal surface, resulting in small "peeling" damage, it can lead to stress concentration contact areas, both the result of stress concentration causing metal surface crack spread, and ultimately shorten bearing life.

NSK Research shows that by changing the organization bearing steel, the bearing can be improved in impurity contamination conditions, or the edge of the working life under lubrication, improve their ability to release stress concentration at the edges.