CAT 320-7332 BUSHING

CAT 320-7332 (3207332) is a Caterpillar heavy-duty steel-backed bimetallic bushing, suitable for boom pins, steering knuckle pins, or counterweight beam pins on Caterpillar 980K/982M loaders, D10T/D10R bulldozers, etc., for radial support and wear protection. The following are the core information:

Core Technical Parameters
Item Details
Part Model: CAT 320-7332 (3207332) Straight-fit bimetallic bushing (steel back + copper alloy, no lubrication holes, suitable for heavy-duty oscillating conditions)

Core Material: Steel back: Low carbon alloy steel (Q235), thickness 2 mm; Liner: Tin bronze (CuSn8P), centrifugally cast, surface Ra≤0.8 μm, self-lubricating and wear-resistant, suitable for heavy-duty oscillating conditions

Key Dimensions: Inner diameter 90 mm, outer diameter 105 mm, length 80 mm, wall thickness 7.5 mm, suitable pin diameter 90 mm (HRC≥58), installation tolerance H7/s6 (interference 0.02–0.04 mm)
Single weight: Approx. 1.9 kg
Compatible models: CAT 980K/982M loaders (boom pin/link pin), D10T/D10R bulldozers (balance beam pin/rocker arm shaft), 966M loaders (steering knuckle pin), used for swing connection parts such as boom, steering, and suspension
Working adaptability: Maximum radial load 120 kN, operating temperature -20℃ to +120℃, compatible with lithium-based grease (NLGI 2), wear life ≥5000 working hours
Core functions and structural features: Bimetallic composite structure: Steel backing provides high-strength support, tin bronze lining reduces friction and wear, friction coefficient f≤0.15, suitable for heavy-duty swing conditions, reducing pin and hole wear.

No lubrication hole design: Suitable for pre-lubricated pins or centralized lubrication systems, supplying oil through the pin lubrication channel, avoiding localized wear caused by blocked lubrication holes.

Interference fit fixation: The outer diameter interferes with the mounting hole by 0.02–0.04 mm, ensuring no looseness after installation, guaranteeing coaxiality, suppressing wobbling and eccentricity, and reducing vibration and noise.

Impact and deformation resistance: Structural yield strength ≥300 MPa, adaptable to the impact loads and load fluctuations of engineering machinery, preventing deformation and cracking, and extending component life.

Installation and maintenance points:
Installation specifications: Clean the mounting hole and pin. Mounting hole Ra≤1.6 μm, pin diameter tolerance h6 (0–-0.03 mm), HRC≥58.

Cold press or heat the mounting hole (≤100℃) for assembly. The bearing end face is flush with the mounting hole end face, with an interference fit of 0.02–0.04 mm to avoid deformation.

After installation, apply lithium-based grease (NLGI 2) to ensure sufficient lubrication between the pin and the inner liner.

Maintenance Recommendations:

Inspect every 800 working hours: check for bearing clearance > 0.2 mm, inner liner wear, and surface scratches; replace immediately if necessary. Simultaneously check pin wear (> 0.1 mm requires repair).

When replacing parts, prioritize original equipment manufacturer (OEM) or certified parts to ensure material, dimensional accuracy, and surface treatment meet standards.

Simultaneously check the lubrication system, clean lubrication channels, and ensure effective lubrication.