CAT 421-3805 BUSHING

CAT 421-3805 (4213805) is a Caterpillar steel-backed + copper-lead alloy bimetallic bushing, suitable for swing connections such as boom pins, connecting rod pins, and balance beam pins on CAT 980K/982M loaders and D10T/D10R bulldozers. It provides radial support and wear protection. Key information is as follows:

Key Technical Parameters
Item Details
Part Model: CAT 421-3805 (4213805) Straight-fit bimetallic bushing (steel backed + copper-lead alloy, no lubrication holes, suitable for heavy-duty swing conditions)

Core Materials: Steel backed: Low-carbon alloy steel (Q235), thickness 2 mm; Liner: Copper-lead alloy (CuPb24Sn4), centrifugally cast, surface Ra≤0.8 μm, self-lubricating and wear-resistant, suitable for heavy-duty swing conditions

Key Dimensions: Inner diameter 95 mm, outer diameter 110 mm, length 90 mm mm diameter, wall thickness 7.5 mm, compatible pin diameter 95 mm (HRC≥58), installation tolerance H7/s6 (interference 0.025–0.045 mm)
Single weight Approx. 2.5 kg
Compatible models CAT 980K/982M loaders (boom pin/rocker arm shaft), D10T/D10R bulldozers (balance beam pin/link pin), 966M loaders (steering knuckle pin), used for swing connection parts such as boom, steering, and suspension
Working adaptability Maximum radial load 150 kN, working 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, copper-lead alloy 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 0.025–0.045 mm, ensuring no looseness after installation, guaranteeing coaxiality, suppressing sway and eccentricity, and reducing vibration and noise.

Impact and deformation resistance: Structural yield strength ≥320 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 0.025–0.045 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.