CAT 523-3712 BUSHING-SEM

CAT 523-3712 is a Caterpillar genuine SEM series straight-sleeve heavy-duty bushing, suitable for the pivot parts of loaders, excavators, booms, sticks, etc., for heavy-duty, low-speed swinging operations. The following is pure original data and does not include replacement parts information.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model 523-3712, Type SEM straight sleeve bushing, Material steel back + high-strength brass alloy (CuZn25Al5), Single weight 1.2 kg, Applicable working conditions heavy load, low-speed oscillation, Working temperature -25℃ to +150℃, Rated bearing pressure ≥250 MPa, Friction coefficient ≤0.10 (oil lubrication), Compatible with Cat 950M/962M loaders, 336F/349F excavator boom pins, stick cylinder pins, etc.

Key Dimensions (Metric / Imperial)
Inner diameter 50.80 mm (2.000 in, tolerance +0.02/-0 mm), Outer diameter 63.50 mm (2.500 in, tolerance +0.03/-0 mm), Length 76.20 mm (3.000 in, tolerance ±0.1 mm) 6.35 mm wall thickness (0.250 in, tolerance ±0.02 mm), end face perpendicularity ≤0.02 mm, inner hole roughness Ra≤0.8 μm, suitable shaft diameter φ50.80-50.83 mm, installation interference 0.03-0.05 mm

Performance Parameters: Fatigue life ≥1.2×10⁶ cycles (200 MPa load), wear resistance ≥5000 hours (oil lubrication condition), steel backing hardness HB 180-220, brass layer hardness HB 90-110, suitable mounting hole diameter φ63.50-63.53 mm

Structure and Fitting Characteristics: Composite material structure: The steel backing provides high-strength support, and the high-strength brass alloy layer has excellent wear resistance and self-lubricating properties, suitable for low-speed heavy-load and frequent oscillation conditions, reducing pin wear.

Precise Size Fit: The groove-free and oil-hole-free design accommodates pins and mounting holes of specific diameters. An interference fit ensures no loosening after installation, guaranteeing stable equipment operation.

Strong Compatibility: Compatible with key components such as the boom and stick of equipment like the Cat 950M/962M loaders and 336F/349F excavators. Precisely matches original pins and mounting holes, requiring no additional machining.

Installation and Maintenance Points (Original Data)

Installation: Clean the mounting holes and pin surfaces (free of oil, burrs, and rust). Use cold-press installation (pressure ≤100 kN). After installation, the bearing end face should be flush with the mounting surface, without skewing. The pin should rotate freely without jamming, and the clearance between the bearing and the mounting hole should be ≤0.01 mm.

Maintenance: Check lubrication every 500 hours to ensure sufficient grease between the pin and the bearing (Cat HD EP 2 grease recommended); periodically check bearing wear, and replace when the inner diameter wear exceeds 0.15 mm; for long-term storage, apply anti-rust oil and seal to prevent moisture.