The basic type of deep groove ball bearing consists of an outer ring, an inner ring, a group of steel balls and a group of cages. There are two types of deep groove ball bearing, single row and double row, deep groove ball structure is also divided into sealed and open two kinds of structure, open refers to the bearing without sealing structure, sealing type deep groove ball is divided into dust seal and oil seal. The dust proof sealing cover is made of steel plate stamping, which only prevents dust from entering the bearing raceway. The oil-proof type is contact oil seal, which can effectively prevent the grease spillover in the bearing.