CAT 077-4449 BEARING

CAT 077-4449 is a Caterpillar genuine tapered roller bearing used for shaft end support and positioning in transmission systems such as gearboxes and transfer cases. The following is the original data and does not include replacement parts information.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model 077-4449, Type: Single-row tapered roller bearing (including inner and outer rings and roller assembly), Material: Chromium-molybdenum alloy steel (52100), Weight: 0.85 kg, Applicable operating conditions: Medium speed and medium load, combined axial and radial loads, Operating temperature: -40℃ to +150℃, Rated dynamic load ≥125 kN, Rated static load ≥190 kN, Fits shaft diameter φ65 mm, Used for gearbox output shaft and transfer case input shaft support

Key Dimensions (Metric/Imperial)
Inner diameter: 65.0 mm (2.559 in, tolerance 0/-0.015 mm), Outer diameter: 120.0 mm (4.724 in, tolerance 0/-0.025 mm), Width: 35.0 mm (1.378 in, tolerance ±0.1 mm), Number of rollers: 16, Roller cone angle: 15°, inner ring large end diameter 92.0 mm, outer ring small end diameter 88.0 mm

Performance Parameters: Material hardness HRC 60-64, roller surface roughness Ra≤0.2 μm, limiting speed 2800 rpm (oil lubrication), maximum allowable radial load 110 kN, maximum axial load 45 kN, compatible lubricant Cat DEO-ULS 15W-40, impact resistant, wear resistant, can compensate for shaft misalignment ≤0.5°

Structure and Compatibility Characteristics:

Combined Load-Bearing Function: The tapered roller structure can simultaneously withstand radial loads and unidirectional axial loads, suitable for parts requiring bidirectional positioning such as gearbox output shafts and transfer case input shafts, preventing shaft movement and vibration.

Precision Positioning Design: The inner and outer rings adopt a precision tapered fit. After installation, the clearance is adjusted by preload to ensure shaft coaxiality and rotational accuracy, reducing transmission system noise and wear.

Operating Condition Adaptability: Made of chromium-molybdenum alloy steel, quenched to achieve high hardness and toughness, it is suitable for engineering machinery operating conditions with frequent start-stop cycles and large load fluctuations. Long-term roller wear is ≤0.02 mm.

Installation and Maintenance Points (Original Data)

Installation: Clean the journal and bearing housing bore (free of oil and burrs). Use hot mounting (inner ring heated to 80-100℃) or cold pressing. After installation, ensure the bearing end face fits snugly against the shaft shoulder, with axial clearance controlled at 0.03-0.08 mm. Tighten the bearing cap bolts in a symmetrical, cross-hatched sequence, using torque values ​​according to the original manufacturer’s specifications (typically 60-80 N·m).

Maintenance: Check bearing temperature and vibration every 1500 hours. If the temperature exceeds 80℃ or vibration is abnormal, stop the machine for inspection. Change the lubricating oil regularly; the oil level should cover half the bearing height. For long-term storage, apply rust-preventive oil and seal to prevent corrosion.