Identification of rolling bearings

According to national standards, rolling bearing codes are represented by Hanyu Pinyin letters and Arabic numerals, and are generally represented by a set of numbers to indicate the structure, type and inner diameter size of the bearing. The regulations are expressed in seven digits:

The first and second digits from the right indicate the bearing inner diameter;

The third digit from the right indicates the bearing diameter series;

The fourth digit from the right indicates the bearing type code;

The fifth and sixth digits from the right indicate the structural characteristics of the bearing;

The seventh digit from the right indicates the width or height series of the bearing.

More than seven digits, from the left, the first digit from the left indicates the bearing clearance, and the second digit from the left indicates the bearing accuracy level, such as G (normal), E (advanced), D (precision level), C (super precision level). Usually, the code number of rolling bearings is expressed in four digits, and the meaning of the four digits is shown in Table 1-2.

Table 1-2 Significance of rolling bearing designations

Number of bits (right-to-left)	Numbers represent meaning	Codename
1	2	3	4	5	6	7	8	9
First and second digits	Bearing bore diameter	When the code number < 04, 00, 01, 02, 03, respectively, indicates that the bearing inner diameter = 10, 12, 15, 17mm, the code number is 04 ~ 99, the code number is multiplied by 5, that is, the inner diameter size of the bearing.
Third digit	Bearing diameter series	Extra light series	Light and narrow series	Medium narrow series	Heavy narrow series	Light and wide series	Medium wide series		Ultralight series
Fourth digit	Bearing type	Centripetal ball bearings	Spherical ball bearings	Short contiguous cylindrical roller bearings	Spherical roller bearings	Needle roller bearings	Screw roller bearings	Angular contact ball bearings	Tapered roller bearings	Thrust ball bearings	Thrust roller bearings

Note: The leftmost "0" when marking the code is not written.