CAT 528-7406 Sleeve Bearing

CAT 528-7406 is a Caterpillar genuine steel-backed bronze alloy straight-tube sleeve bearing (without oil grooves/oil holes), suitable for the boom/stick hinge points and rocker arm bushings of Cat 320D2/323D2 excavators and 966M loaders. Its core function is to withstand radial loads and oscillating friction under medium to heavy load conditions, suitable for low-speed, high-frequency oscillation scenarios. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes
Model: 528-7406, Type: Straight-tube sleeve bearing (without oil grooves/oil holes), Suitable for Cat medium to large equipment boom/stick/rocker arm hinge systems, Material: Steel back + bronze alloy (CuSn8P), Inner diameter: φ55 mm (compatible with φ55 mm pins), Outer diameter: φ63 mm, Total length: 40 mm, Single weight: approximately 0.22 kg, Rated radial load: 28 kN, Operating temperature: -40℃ to +120℃, fits shaft tolerance h8, fits seat tolerance H7, suitable for low to medium speed (≤500 rpm) and medium to heavy load conditions.

Key Dimensions: Inner diameter tolerance 0/-0.020 mm, outer diameter tolerance +0.025/-0.010 mm, length tolerance ±0.15 mm, wall thickness 4 mm, chamfer at both ends 1.5×45°, coaxiality ≤0.03 mm, radial clearance 0.015-0.025 mm, steel backing thickness 1.2 mm, bronze alloy layer thickness 2.8 mm.

Material and Manufacturing Process: The steel backing is made of low carbon steel (SPCC, thickness 1.2 mm, hardness HB 120-150), tin-plated for rust prevention; the bronze alloy layer is CuSn8P (containing 8% tin and 0.15% phosphorus, hardness HB 80-100, tensile strength ≥350 MPa), with no oil grooves on the surface. Oil-free design, lubricated by mating pins; bronze layer surface roughness Ra≤0.8 μm; steel backing and bronze layer are metallurgically bonded with a bonding strength ≥150 MPa. Compatible with Cat 320D2/323D2/326D2 excavator boom-stick hinge bushings, 966M/972M loader rocker arm bushings, and D6K/D7E bulldozer blade connection bushings. Used for hinge point swing support, compatible with φ55 mm pins, installed between the support and the pin, bearing radial loads. Assembly fit: clearance fit with the pin (0.015-0.025 mm), interference fit with the support (0.010-0.020 mm); rear end face runout ≤0.05 mm; no jamming during swinging; axial movement ≤0.1 mm. Installation and Maintenance Points: Before installation, clean the pin, support, and sleeve bearing. Check for damage to the bearing inner bore and any peeling of the bronze layer. Press the sleeve into the support using a cold pressing method. Do not directly strike the bearing end face to prevent deformation.

After installation, check for smooth movement and no abnormal noise. Check every 800 hours. Replace the bearing immediately if the inner diameter wear is >0.1 mm or if the bronze layer shows peeling/cracks.

Lubrication Maintenance: Apply Cat-specific lithium-based grease to the pin surface before installation. Replenish every 500 hours. In humid/dusty conditions, shorten this to 300 hours to ensure adequate lubrication of the hinge points and reduce wear.