Do Sealed Bearings Require Refueling?

No, you don't need to Bearings with sealed covers on both sides, whether rubber sealed caps or steel stamped seal covers, do not require refueling.

Bearing designers, in order to achieve the best life value of the bearing, filled with what label of grease, grease filling amount, is after countless practical experiments to obtain the best, the most scientific solution. It is generally believed that the life of grease depletion is comparable to that of bearings. In addition, the design of the seal cover, the distance from the inner ring, or contact, or non-contact, or maze are designed. The disassembling of the sealing cover when refueling will inevitably affect its effect, and thus the service life of the bearing.

Take NSK as an example: 6305DDUCM NS7S, NS7 is a grease label, its chemical composition is strictly confidential. S is the label of grease filling volume, but also strictly confidential!