CAT 446-6589 47.752mm Straight Sleeve Bearing

CAT 446-6589 is a Caterpillar genuine bimetallic composite bushing, suitable for articulated joints in engineering machinery, used to reduce friction and absorb shock. The following is structured raw data, excluding replacement parts information from the Cat® Parts Store.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model 446-6589, type is bimetallic composite bushing (steel back + copper-lead alloy layer), steel back material Q345B, alloy layer material CuPb15Sn8 (copper-lead-tin alloy), steel back thickness 2 mm, alloy layer thickness 2.5 mm, single weight 0.45 kg, working temperature -40℃ to +120℃, lubrication method is oil lubrication/grease lubrication, suitable for medium and low speed, medium and heavy load, oscillating/rotating conditions, used in hinge pins, drive shafts, etc.

Key Dimensions
Inner diameter 45 mm (1.772 in), outer diameter 55 mm (2.165 in), length 60 mm (2.362 in), chamfer at both ends 1×45°, steel back outer diameter tolerance h6, alloy bushing inner diameter tolerance H7, clearance with shaft 0.010-0.022 mm, interference fit with bearing housing 0.008-0.018 mm
Compatible Models and Parts: Compatible with Cat 307 excavators, 420F2 and 430F2 loaders, and 446D and 446E backhoe loaders for boom articulation pins, stick pins, and steering knuckle pins. One piece per part. Bears radial load + slight impact load. Suitable for swing angles ≤ ±30° and speeds ≤ 500 r/min.
Performance Parameters: Radial load capacity ≥ 70 kN, coefficient of friction ≤ 0.04 (oil lubrication), wear rate ≤ 0.004 mm/1000 hours, fatigue life ≥ 7500 hours, alloy layer hardness HB 75-95, steel backing tensile strength ≥ 470 MPa, steel backing and alloy layer bonding strength ≥ 190 MPa
Structural and Performance Advantages:
Bimetallic composite structure: Q345B steel backing provides high strength and rigidity, CuPb15Sn8… The alloy layer possesses excellent anti-galling and embedding properties, absorbing impurities and reducing wear on shafts and bushings, making it suitable for harsh working conditions in engineering machinery.

Precise dimensional tolerances: Inner and outer diameter tolerances are controlled within ±0.008 mm, ensuring precise fit with hinge pins and bearing housings, preventing loosening and uneven loading, and improving equipment operational stability.

High load-bearing capacity and impact resistance: The alloy layer can withstand impact loads, making it suitable for frequently stressed parts such as booms and sticks, reducing vibration and noise, and extending the service life of pins and bushings.

Original manufacturer guarantee: Manufactured by Caterpillar, the alloy layer and steel backing have high bonding strength, eliminating the risk of delamination, ensuring strong compatibility, and avoiding jamming failures caused by dimensional deviations.

Installation and Maintenance Points (Original Data)

Installation Procedure: Clean the surfaces of the bushing, shaft, and bearing housing. The bearing housing bore tolerance is H7. Press the bushing into the bearing housing using a cold pressing method (interference 0.008-0.018 mm). After installation, check the inner bore roundness to be ≤0.008 mm and the shaft clearance to be 0.010-0.022 mm to ensure no jamming.

Maintenance Cycle: Check lubrication status every 250 hours, replenish grease (Cat 1U-8886 recommended) every 1200 hours, and check bushing wear every 5500 hours. Replace the bushing when the inner bore wear exceeds 0.08 mm.

Common Troubleshooting: Insufficient lubrication can cause overheating and wear of the bushing, requiring inspection of the lubrication system; impurities can cause scratches on the alloy layer, requiring cleaning and replacement of the bushing; insufficient interference can cause the bushing to loosen, requiring re-pressing or replacement of the bearing housing.