Deep Groove Ball Bearing

1. Basic Designation

The basic designation is composed of type code + dimension series code + bore code.

• Type code: 6 stands for deep-groove ball bearing.
• Dimension series code: Two-digit number. The first digit is the width series; the second digit is the diameter series. It comprehensively reflects the outer diameter and width of the bearing. Common series include 19, 00, 10, 02, 03, 04, with load-carrying capacity increasing sequentially.
• Bore code: Indicates the nominal bore diameter (d) of the bearing.

Dimension series code (middle digits)

Combination of width series and diameter series, determining bearing thickness and load capacity.

• 0 (or omitted): Extra-light series (e.g. 6000)
• 2: Light narrow series (e.g. 6200), widely used
• 3: Medium narrow series (e.g. 6300), higher load-carrying capacity
• 4: Heavy narrow series (e.g. 6400), heavy load capacity
• 8, 9: Thin-wall series (e.g. 6800, 6900), for space-limited applications

2. Suffix Codes

Suffix codes indicate modified features such as bearing construction, seals, cage type and tolerance class.

3. Radial Internal Clearance

• C0 (or CN): Normal clearance group, usually omitted in marking.
• C2: Clearance smaller than normal group.
• C3: Clearance larger than normal group (commonly used for hightemperature conditions, interference fits and other working conditions).

4. Tolerance Classes

• P0: Normal grade (standard), generally omitted.
• P6: High grade.
• P5 / P4: Precision grade / superprecision grade (for machinetool spindles, etc.)