CAT 552-4635 Sleeve Bearing

CAT 552-4635 is a steel-backed aluminum-coated straight sleeve bearing (shaft sleeve) used by Caterpillar for drive systems. It is suitable for the final drive, gearbox, or hydraulic pump of excavators and loaders. Its core function is to provide radial support and wear reduction for the shaft system, absorb vibration and withstand medium loads. It is a key component for smooth operation of the drive system and is suitable for medium-low speed and medium-heavy load conditions. It has excellent shock resistance and wear resistance. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 552-4635, Type: Straight-type unscrewed sleeve bearing (steel-backed aluminum-based alloy), Material: Steel back + high-tin aluminum-based alloy (Steel back Q235, aluminum layer tin content 12%-15%, hardness HB 80-100), Uncoated surface (aluminum layer self-lubricating, with axial lubrication grooves), Single weight approximately 0.82 kg, Operating temperature: -30℃ to +160℃, Installation method: Cold pressing/Hot fitting (interference fit), Design life ≥10000 hours (normal operating conditions)

Key Dimensions
Inner diameter: 101.6 mm (4 inches, tolerance 0/+0.02 mm), Outer diameter: 120.65 mm (4.75 inches, tolerance 0/-0.018 mm), Total length: 76.2 mm (3 inches, tolerance 0/-0.1 mm), Number of lubrication grooves: 4 Strips (uniformly distributed, 3 mm wide, 1 mm deep), inner hole surface roughness Ra≤0.4 μm, outer circle cylindricity≤0.01 mm, end face parallelism≤0.02 mm
Compatible Models and Parts: Compatible with Cat 323D2 and 330D2 excavators (final drive planetary gear shaft), 972M loader (gearbox input shaft), 3516B diesel engine (auxiliary drive shaft), with matching 241-3818 fixed race, 103-8329 elastic retaining ring, 5V-5498 retainer, 366-9273 straight sleeve bearing (installed in the same group)

Performance Parameters: Radial rated load ≥80 kN, allowable linear velocity ≤5 m/s, coefficient of friction ≤0.08 (boundary lubrication), wear rate ≤0.005 mm/1000 hours, interference fit 0.04-0.06 mm (cold fitting), hot fitting temperature 80-100℃, impact load ≥25 kN, grease lubrication (Cat 5P-0960 grease recommended)

Structural and Performance Advantages: Steel-backed aluminum composite structure. The steel back ensures high strength and rigidity, while the aluminum alloy layer provides excellent friction reduction and self-lubrication, suitable for boundary conditions without sufficient lubrication, preventing seizing caused by dry friction between the shaft and bearing.

Axially distributed lubrication groove design stores grease, forming a stable oil film, reducing friction loss, absorbing transmission system vibration, reducing impact between components, protecting journals and bearing housings, and improving transmission system reliability.

Straight structure without flanges, suitable for various shaft diameters, flexible installation methods (cold pressing/hot mounting), adaptable to different maintenance scenarios. The steel back and aluminum layer are firmly bonded, eliminating the risk of delamination, suitable for frequent start-stop and variable load conditions.

Installation and Maintenance Points:
**Before installation, clean the journal, bearing inner bore, and bearing housing bore. Check for burrs and rust. Measure the shaft diameter (101.6 mm) and bearing inner diameter, as well as the bearing housing bore and bearing outer diameter, ensuring the interference fit meets requirements. For cold installation, use a special press to apply even pressure. For hot installation, heat the bearing to 80-100℃ and quickly install it into the bearing housing bore.

After installation, check the fit between the bearing end face and the bearing housing. Ensure there is no gap or misalignment, and that the rotating shaft system rotates smoothly without jamming. Add the recommended grease, ensuring the lubrication grooves are full.

Maintenance: Check bearing wear and lubrication condition every 2000 hours. If the aluminum layer peels off, wear exceeds 0.1 mm, or the grease deteriorates, replace immediately. When replacing, replace the entire bearing; do not repair the aluminum layer and reuse it, as this will worsen journal wear.