CAT 446-7244 BEARING

CAT 446-7244 is a Caterpillar genuine single-row cylindrical roller bearing, suitable for the gearboxes, drive axles, or hydraulic pumps/motors of loaders, excavators, and other equipment. It is used to withstand pure radial heavy loads and is compatible with the input shafts, intermediate shafts, or planetary gear shaft ends of models such as the 950M/966M loader, 320GC excavator, and C13 engine hydraulic pumps.

Core Technical Parameters

Item Details
Part Model: CAT 446-7244 Single Row Cylindrical Roller Bearing

Material: Inner/outer rings are made of chromium-molybdenum alloy steel (e.g., 42CrMo), rollers are made of GCr15 bearing steel; surface carburized and quenched, raceway hardness HRC 58-62, roller hardness HRC 60-64, good core toughness, impact resistance and fatigue resistance

Key Dimensions: Inner diameter approx. 80mm, outer diameter approx. 140mm, width approx. 32mm, radial clearance 0.015-0.030mm, suitable for 80mm diameter journals, matching corresponding shaft/bore tolerance IT5-IT6

Compatible Bearings: Often used with CAT 446-7245 cage and 446-7246 seal ring to form a complete bearing assembly, suitable for gearbox two-shaft bearings, drive axle differential bearings, etc.

Performance Characteristics Raceway surface roughness Ra≤0.4μm, contact fatigue life≥6000h, oil and temperature resistant (-40℃ to 120℃), suitable for medium-speed heavy-load (speed ≤2000rpm) and high-frequency vibration conditions.

Core Functions and Structure

Radial Load Bearing: As a single-row cylindrical roller bearing, it only bears pure radial loads. Through line contact between the rollers and the inner and outer raceways, it efficiently transmits loads, improving transmission efficiency. Suitable for pure radial load applications such as gearboxes and drive axles (Cat®…).

Positioning and Guiding: The inner ring has an interference fit with the shaft, and the outer ring has a clearance fit with the housing bore. The cage guides the rollers to be evenly distributed, preventing roller skewing, reducing wear, and ensuring bearing rotational accuracy.

High-Speed ​​Adaptability: The cylindrical roller structure is suitable for medium-to-high-speed rotational conditions. Compared to tapered roller bearings, it is more suitable for pure radial load applications with high speeds, such as hydraulic pump input shaft bearings.

Maintenance: Separable structure (inner ring can be separated from the roller assembly), facilitating installation and disassembly, suitable for quick replacement during equipment overhauls. Installation and Maintenance Points
Installation Specifications
Clean the inner and outer rings, rollers, and mounting surface of the bearing to remove oil, rust, and impurities. Check that the bearing is free of cracks, the rollers are undamaged, the cage is not deformed, and the dimensions meet assembly requirements.

Use heat mounting (heating temperature 80-100℃) for the inner ring and cold mounting for the outer ring. Do not directly strike the raceway surface to prevent damage. After installation, check that the inner ring fits snugly against the shaft without gaps, the outer ring rotates freely in the housing bore, and the coaxiality deviation is ≤0.05mm.

During installation, ensure the cage is intact and the rollers are evenly distributed to avoid roller jamming. Install the matching seals to prevent dust and impurities from entering the bearing.

Maintenance Recommendations
Check every 2500 working hours: for abnormal noise, temperature rise (normal ≤80℃), and vibration. Replace the bearing immediately if any abnormalities are found.

Change the lubricating oil regularly, keeping it clean (NAS 8 cleanliness level) to prevent oil contamination from accelerating raceway wear. Also check the seals to prevent leaks.