FAG 6308-2RSR-C3 Deep Groove Ball Bearing 40x90x23

FAG 6308-2RSR-C3 is a single-row deep groove ball bearing with a 40 mm bore, 90 mm outside diameter and 23 mm width. The FAG suffix 2RSR identifies seals on both sides, while C3 specifies radial internal clearance greater than Normal. These features are part of the complete bearing specification, so the 40x90x23 mm dimensions alone are not sufficient for selecting an equivalent.

FAG 6308-2RSR-C3 - Characteristics

The 6308-2RSR-C3 belongs to the FAG 63 series of single-row deep groove ball bearings. Its deep raceway geometry allows the bearing to carry primarily radial loads while also accommodating axial loads in both directions.

For this specific configuration, the key identification features are the 6308 boundary dimensions, double-sided 2RSR sealing and increased C3 radial internal clearance.

Dimensions

The boundary dimensions of FAG 6308 are:

d - Bore Diameter: 40 mm
D - Outside Diameter: 90 mm
B - Width: 23 mm
Complete Dimensions: 40x90x23 mm

Schaeffler also confirms 40x90x23 mm for the current FAG 6308-C family.

Bearing Construction

FAG 6308-2RSR-C3 is a single-row deep groove ball bearing. The rolling elements are balls running between deep raceways in the inner and outer rings.

This geometry provides radial load capacity while also enabling axial load transmission in both directions. Unlike a single-row angular contact or tapered roller bearing, the basic deep groove design is not limited to axial loading from only one direction.

2RSR Sealing

In FAG terminology, 2RSR identifies contact seals on both sides of the bearing. Schaeffler distinguishes this configuration from 2ZR, which identifies shields on both sides.

The seals help protect the rolling elements and raceways against contamination and retain lubricant inside the bearing. Consequently, a 6308-2RSR and a 6308-2ZR should not be considered technically identical solely because their boundary dimensions are the same.

C3 Radial Internal Clearance

The suffix C3 means radial internal clearance greater than Normal. It describes bearing clearance, not quality or accuracy class.

Radial internal clearance can decrease after mounting because of interference fits and can change further in operation due to temperature differences between the inner and outer rings.

For this reason, a 6308-2RSR with Normal clearance should not automatically replace 6308-2RSR-C3 when C3 is specified for the bearing arrangement.

JN Cage

Schaeffler specifies the JN cage as the standard cage design for sealed FAG deep groove ball bearings in the 6300-2RSR to 6314-2RSR range. FAG 6308-2RSR falls within this range.

The cage suffix does not need to appear separately in the designation when the bearing uses the standard cage specified by the manufacturer.

Loads and Operating Principle

The deep groove ball bearing design accommodates radial loads and axial loads in both directions. Actual bearing suitability, however, depends on more than bearing type and dimensions.

Operating load, rotational speed, shaft and housing fits, temperature conditions, lubrication, contamination and required service life should be considered when verifying the bearing arrangement.

Meaning of FAG 6308-2RSR-C3

The designation identifies the bearing configuration as follows:

6308: single-row deep groove ball bearing, 63 series
2RSR: contact seals on both sides
C3: radial internal clearance greater than Normal

The commonly used commercial description FAG 6308 2RS C3 therefore corresponds to a configuration that FAG identifies more precisely using the 2RSR sealing suffix.

Selection and Interchangeability

When selecting an equivalent for FAG 6308-2RSR-C3, verify:

Bearing Type: single-row deep groove ball bearing
Dimensions: 40x90x23 mm
Bore d: 40 mm
Outside Diameter D: 90 mm
Width B: 23 mm
Sealing: contact seals on both sides
Radial Internal Clearance: C3
Load and Speed Capability: suitable for the actual operating conditions

Matching dimensions alone do not establish full interchangeability. A 6308-2ZR-C3, for example, differs in its closure system because 2ZR identifies shields rather than contact seals.

Technical Specification

Manufacturer: FAG / Schaeffler
Catalogue Designation: 6308-2RSR-C3
Type: Single-row deep groove ball bearing
Series: 63
Bore Diameter d: 40 mm
Outside Diameter D: 90 mm
Width B: 23 mm
Dimensions: 40x90x23 mm
Number of Rows: 1
Sealing: Contact seals on both sides
Seal Suffix: 2RSR
Radial Internal Clearance: C3, greater than Normal
Cage: JN, standard cage for the applicable sealed FAG range
Load Direction: Radial and axial in both directions

FAQ

What are the dimensions of FAG 6308-2RSR-C3?

The bearing measures 40x90x23 mm: bore diameter d = 40 mm, outside diameter D = 90 mm and width B = 23 mm.

What does 2RSR mean on FAG 6308-2RSR-C3?

2RSR means contact seals on both sides of the bearing. This is the FAG catalogue terminology for this sealing arrangement.

What does C3 mean?

C3 means radial internal clearance greater than Normal. The clearance class is a functional part of the bearing specification.

What cage is used in FAG 6308-2RSR?

Schaeffler specifies the JN cage as standard for sealed FAG 6300-2RSR to 6314-2RSR deep groove ball bearings, which includes 6308-2RSR.

What loads can FAG 6308-2RSR-C3 accommodate?

As a deep groove ball bearing, it is designed primarily for radial loads and can also accommodate axial loads in both directions.

Are FAG 6308 2RS C3 and 6308-2RSR-C3 the same designation?

"6308 2RS C3" is a common commercial description. FAG uses 2RSR as its catalogue suffix for contact seals on both sides, making 6308-2RSR-C3 the more precise technical identification.

Can 6308-2ZR-C3 replace 6308-2RSR-C3?

Not automatically. 2ZR identifies shields, while 2RSR identifies contact seals. The required sealing arrangement and operating conditions must be considered.

Can 6308-2RSR with Normal clearance replace 6308-2RSR-C3?

Not automatically. The C3 version has greater radial internal clearance, which can affect operating clearance after mounting and at operating temperature.

AI Overview

FAG 6308-2RSR-C3 is a single-row deep groove ball bearing measuring 40x90x23 mm, with contact seals on both sides and C3 radial internal clearance greater than Normal. FAG uses the 2RSR suffix for double-sided contact sealing. The deep groove design accommodates radial loads and axial loads in both directions.