Bearing meaning

ID Code: Under normal circumstances bearing diameter bearing inner code (the basic code of the last two digits) × 5 = internal diameter (mm), Example: 6204 bearing diameter is 04 × 5 = 20mm.
Common special cases:
(I) When the bearing diameter less than 20mm
Bearing diameter size (mm) 10 12 15 17
Corresponding inner code is 00010203
(Ii) When the bearing diameter less than 10mm, the direct use of the basic code of the last one represents the bearing bore size; Example: Bearing 608Z, with a basic code '608 'as the last one eight inner diameter, the inner diameter of the bearing 608Z 8mm. An inner diameter of 627 so 7mm, 634 an inner diameter of 4mm.
(Iii) the bearing bore is not a multiple of 5 is equal to or greater than 500mm, diameter code with a slash '/' character. Another situation: There are some old code needle Stainless steel slewing bearing  iameter code directly using the '/' character. These types of situations '/' behind several values ​​for the bearing bore size. Example below:
Bearing 619/1.5 62/22 60/5003519/11207943/25
Diameter size (mm) 1.5 22 500 1120 25
These are some of the common representation bearing bore, some of the international code of the company are not all the same; should to the actual situation. Specifically to refer to a variety of materials and samples of each manufacturer.
Size code: for expressing the same diameter but the diameter and width of the bearing, see Fig.
Diameter Code ↑
↑

Width Code
OD Series Code: special light (0,1), light (2), middle (3), weight (4)
Width series code: normal width to "0", usually not marked. But for tapered roller bearings (Class 7) and self-aligning roller bearings (3 classes) and other types can not omit the "0"
6010 is slim series, used in light load, high speed; 6210 series is a lightweight, light load speed most reasonable, is the application of the most extensive type; 6310 is the heavy series; 6410 series is re-used for heavy low. Medium and heavy duty most widely used, such as various types of mechanical transmission components, small motors, conveyor lines, motorcycles, etc. Almost all the machinery and equipment used in both types.
Type code: should be remembered that the commonly used bearing code: 3,5,6,7, N 5, corresponding to the old code 7,8,0,6,2 classes. .
Tolerance class code table:
Radial bearings and angular contact ball bearings are divided into five below (High → Low)
New level code P2 P4 P5 P6 P0
Old level code B C D E G
Tapered roller bearings are divided into four below (High → Low)
New level code P4 P5 P6x P0
Old level code C D Ex G (E)
Thrust ball bearings are divided into four below (High → Low)