CAT 3H-9574 Clutch Sleeve

CAT 3H-9574 is a wear-resistant positioning sleeve designed by Caterpillar for the transmission/steering system of heavy machinery. It is mainly used in the connecting rod pins/pivots of loaders and excavators to compensate for the clearance between the shaft and the hole, center and guide, and protect against wear. It is suitable for heavy-load high-frequency oscillation conditions and is a key wear part of the chassis and working device. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 3H-9574, Type: Steel positioning wear-resistant sleeve, Material: Medium carbon alloy structural steel (42CrMo), Surface induction hardening (HRC58-62), Inner hole precision honing, Single weight approximately 0.85 kg, Applicable temperature: -40℃ to +150℃, Suitable grease: Cat Moly Paste, Fit: Interference fit (Sleeve H7 / Shaft j6)

Key Dimensions
Inner diameter: 50 mm (Tolerance H7, Surface roughness Ra≤0.8 μm), Outer diameter: 65 mm (Tolerance g6), Length: 80 mm (Tolerance ±0.12 mm), Wall thickness: 7.5 mm, Chamfer at both ends: 2 mm × 45°, Inner hole cylindricity ≤0.005 mm, Coaxiality ≤0.01 mm, Installation interference: 0.015-0.030 mm

Suitable Models and Applications Compatible with Cat 950G/966G loaders and 320C/325C excavators, used for boom-stick connecting pins, steering knuckle pivots, and connecting rod pin bushings. Matching parts include pivot pins, lock nuts, and dust seals. Rated load capacity ≥250 MPa, fatigue life ≥8000 hours.

Performance Parameters: Tensile strength ≥1080 MPa, yield strength ≥930 MPa, hardness gradient (within 5 mm of surface) HRC55-62, coefficient of friction ≤0.12 (lubricated state), impact toughness ≥60 J/cm², corrosion resistance meets ISO 9227 neutral salt spray test ≥48 hours with no red rust.

Structural and Performance Advantages: High strength and wear resistance: 42CrMo material + induction hardening, surface hardness reaches HRC58-62, good core toughness, can withstand heavy-load impact and wear, suitable for high-frequency oscillating conditions in construction machinery.

Precision Positioning: The inner bore has an H7 tolerance and is honed, ensuring an interference fit with the pivot pin, guaranteeing connection accuracy, reducing radial runout, lowering the clearance between the pin and the sleeve, and extending overall service life.

High Adaptability: Chamfered ends facilitate installation, and uniform wall thickness ensures balanced stress distribution, adapting to various heavy-duty conditions. It perfectly matches original factory pivot pins, dust rings, and other accessories, reducing maintenance costs.

Installation and Maintenance Points: Before installation, clean the inner and outer surfaces of the sleeve and the mounting hole, checking for burrs and cracks; use cold fitting or press fitting (pressure ≤10 kN, applied to the end face), and do not strike the inner bore; after installation, the rear face runout should be ≤0.02 mm, rotation should be smooth, and the clearance should meet design requirements.

Trial run for 30 minutes, sleeve temperature ≤80℃, no abnormal noise or vibration; check wear and lubrication status every 500 hours, replenish grease every 1000 hours, and replace the sleeve when the inner bore wear exceeds 0.20 mm. When replacing, the original pivot pin must be matched to ensure the interference fit and tolerance, and avoid non-standard parts that may cause poor fit and premature failure.