CAT 624-3921 BEARING

CAT 624-3921 is a Caterpillar genuine single-row cylindrical roller bearing (with cage, no seal), suitable for the gearboxes, transfer cases, or hydraulic pump drives of mini excavators and loaders. It features high radial load capacity and high speed adaptability, making it suitable for medium-to-high speed, continuous radial load conditions. The following are the key information.

Core Technical Parameters

Item Details
Part Model: CAT 624-3921 (Single Row Cylindrical Roller, Stamped Steel Cage, No Seal/Dust Cover, Straight Raceway)

Material: Inner ring, outer ring, and rollers are all made of 52100 high-carbon chromium bearing steel, integrally hardened (HRC 60-64), hardened layer depth ≥ 1.2 mm; suitable for -40℃ to +120℃, compatible with oil/grease lubrication

Key Dimensions: Inner diameter 40 mm (1.575 in), outer diameter 68 mm (2.677 in), width 15 mm (0.591 in), roller diameter 4.5 mm, number of rollers 20, chamfer 1.0 mm

Single Weight: Approx. 0.21 kg (0.463 lbs)

Tolerances and Geometric Positions: Inner diameter tolerance m6 (+0.012/+0.002 mm), outer diameter tolerance… h6 (0/-0.019 mm), radial clearance C3 (0.015-0.028 mm), rotational accuracy P0
Load capacity: Radial rated dynamic load 42.2 kN, radial rated static load 40.5 kN, limiting speed 9000 rpm (oil lubrication) / 6300 rpm (grease lubrication)
Structure and core functions:
High-speed radial load: Cylindrical roller line contact design, suitable for high-speed rotating parts such as gearbox shafts and hydraulic pump drive shafts, maintaining stable radial load at high speeds and reducing rolling friction loss.

Uniform load distribution: Stamped steel cage precisely positions the rollers, avoiding roller tilting or poor contact, ensuring uniform load transfer and extending bearing life.

Flexible assembly: Separable inner/outer ring structure, convenient for installation and disassembly, suitable for batch maintenance scenarios, reducing assembly time.

Wear-resistant and fatigue-resistant: Made of 52100 bearing steel with an integral quenching process, it possesses excellent resistance to pitting and fatigue, making it suitable for the complex working conditions of construction machinery involving frequent start-stop and continuous operation.

Compatible Models and Application Scenarios

Compatible Equipment: CAT 306E2/307E2 mini excavators, 906M/907M loaders, 420F2 backhoe loaders, C4.4 engine-equipped hydraulic pumps/transmissions.

Core Applications: Used for transmission intermediate shaft support, hydraulic pump drive shaft bearings, transfer case output shaft bearings, and the front end of the travel motor reduction mechanism, suitable for medium-to-high speed (≤6000 rpm) radially predominant load conditions.