CAT 431-5968 Sleeve Bearing (Bushing)

CAT 431-5968 is a steel-backed copper-coated straight-tube positioning sleeve for Caterpillar hydraulic pumps/swing motors. It is suitable for positioning and radial support of the main pump drive shaft/swing gearbox output shaft in Cat 320/323/326 GC excavators, 950GC loaders, and other models. Its core function is to eliminate radial runout of the shaft system, ensure transmission coaxiality, and withstand light-load radial forces. The following is professional structured information from Cat® Parts.

Core Parameters (Professional Version)

Project Details
Basic Attributes
Model 431-5968, 1 unit per unit (main pump end positioning), compatible shaft diameter 38 mm, matching bearing 476-3240, bearing cover 510-0119, single weight 0.8 kg, used for positioning and radial support of hydraulic pump drive shaft/rotary gearbox output shaft

Key Dimensions
Inner diameter 38 mm (tolerance H7: 0–+0.025 mm), outer diameter 50 mm (tolerance g6: 0–-0.019 mm), total length 45 mm, positioning step height 5 mm (tolerance ±0.1 mm), oil groove width 3 mm (depth 0.5 mm, 4 evenly distributed around the circumference), chamfer at both ends 1×45° (tolerance ±0.1 mm)

Material and Process
Material is steel back copper sleeve (outer layer 45# steel, inner layer CuPb10Sn10) Bronze (bonding strength ≥100 MPa), inner bore surface oil-impregnated (porosity 15%–20%), outer surface galvanized and passivated (salt spray test ≥48 hours), inner bore roughness Ra≤0.8 μm, end face flatness≤0.02 mm

Performance Parameters: Rated radial load ≥800 N, operating temperature -20℃ to +120℃, linear speed ≤0.3 m/s, wear life ≥8000 hours (continuous operation), compatible with Cat DEO-ULS hydraulic oil, no damage during short-term operation (≤10 minutes) without lubrication

Compatible Models: Cat 320GC/323GC/326GC excavators, 950GC/962GC loaders, M318F wheeled excavators, matching main pump model 359-0677, swing motor 416-6312 Installation and Maintenance Points: Before installation, clean the inner and outer surfaces of the sleeve and the mounting hole. The mounting hole needs to be bored to φ50H7 (tolerance 0–+0.025 mm). Use cold fitting (freeze at -20℃ for 1 hour) before pressing in, with a pressing force ≤30 kN, ensuring the sleeve end face fits snugly against the mounting surface (gap ≤0.03 mm).

Maintenance Cycle: Every 1000 hours, check the sleeve radial clearance (replace if clearance >0.2 mm), replenish grease (Cat MTO-1000), check the oil groove for unobstructed flow, and replace the seal immediately if leakage is found.

Troubleshooting: If shaft vibration/abnormal noise occurs, first check for sleeve wear, deformation of the positioning step, and wear of the mounting hole. Replace the sleeve and repair the mounting hole if necessary.