Deep groove ball bearings have various types of structure. Not only the open type bearings are provided, but also the bearings with shield or seal at one side, shields or seals at both sides. The seal ring can be divided into contact and non-contact (low friction) according to contact ways. Usually the bearings with seals at both sides have been filled with grease lubricant before delivery. The filler amount would be 25%-30% of the effective space in bearings. If customers have special requirements, other types of greases can be filled and the filler amount could be adjusted accordingly. The bearings sealed at both sides are forbidden to washed. Bearings with seals can maintain their reliable operation at working temperature between ?30¡æ and 100¡æ. Contact sealed bearings should not be chosen to use in high speed working conditions, because the friction existing between seal and inner ring of the bearing would make the ambient temperature higher than that of non-contact sealed bearings. As a consequence, contact sealed bearings are suitable for middle or slow speed working conditions.
