CAT 126-0794 BUSHING

CAT 126-0794 is a Caterpillar steel-bronze composite bushing commonly used in the boom, stick, or connecting rod pins of excavators and loaders. It serves to resist wear, reduce friction, and provide positioning. It is compatible with Cat 320D and 336D series excavators and 950M and 966M loaders, and is a key component to ensure the flexible operation of the articulated parts of the working device. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 126-0794, Type: Composite Sleeve Bushing, Material: Outer layer 42CrMo alloy steel, Inner layer tin bronze (CuSn10Pb10), Single weight approximately 1.2 kg, Applicable temperature -20℃ to +100℃, Outer layer hardness HRC50-55, Inner layer hardness HB80-100, Coefficient of friction ≤0.15 (dry friction), ≤0.08 (oil lubrication)

Key Dimensions
Inner diameter 60 mm (tolerance 0 to -0.015 mm), Outer diameter 80 mm (tolerance +0.018 to +0.030 mm), Length 55 mm (tolerance ±0.12 mm), Step diameter 72 mm, Step length 10 mm, Chamfer 1.5 mm × 45°, Inner diameter surface roughness Ra≤0.4 μm, Outer diameter surface roughness Ra≤0.8 μm, clearance 0.05-0.10 mm
Compatible Models and Applications: Compatible with Cat 320D, 323D, and 336D excavators, and 950M and 966M loaders. Used for boom and stick hinges, stick and bucket connections, and connecting rod and rocker arm pin joints. Supporting parts include pins, dust seals, and grease fittings. Rated load capacity ≥120 MPa, fatigue life ≥8000 hours.
Performance Parameters: Rated radial load ≥120 kN, allowable linear velocity ≤1.5 m/s, lubrication method: oil lubrication (Cat DEO-ULS recommended) or grease lubrication (Cat Moly Grease recommended), grease filling amount 8-12 g, corrosion resistance meets ISO 9227 neutral salt spray test ≥72 hours without rust, radial runout after assembly ≤0.06 mm. mm
Structural and Performance Advantages

Composite Wear Resistance: The outer alloy steel layer provides high strength and rigidity, while the inner tin bronze layer offers excellent friction reduction and embedding properties, suitable for reciprocating oscillation conditions in hinged parts, reducing the wear rate of pins and bushings.

Precise Positioning: The stepped structure enables axial positioning, preventing bushing movement on the pin. The chamfered design facilitates installation and is suitable for complex engineering machinery operating environments.

Long-Term Stability: The composite material is suitable for heavy-load and impact conditions. The inner bronze layer stores lubricating oil, forming an oil film, reducing the risk of dry friction and extending the service life of parts.

Simple Maintenance: Cold-press assembly is possible during installation, requiring no complex tooling. Regular grease replenishment via grease fittings results in low maintenance costs and suits rapid on-site repair needs.

Installation and Maintenance Points:
**Before installation, clean the bushing, pin hole, and pin, checking for burrs and cracks.** Use cold pressing (pressure ≤25 kN, applied to the bushing end face), and do not strike the inner bronze surface. After installation, ensure the bushing fits tightly against the hole wall without looseness, with a radial clearance of 0.05-0.10 mm and no jamming during movement.

Perform a 2-hour trial run. The temperature of the hinge area should be ≤65℃, with no abnormal noise or wear. Check the lubrication status every 500 hours and replenish grease. Check the bushing wear every 2000 hours. Replace the bushing when the inner diameter wear exceeds 0.2 mm or when scoring or peeling occurs.

When replacing, prioritize original parts, ensuring that the inner and outer diameter dimensions, material, and fit clearance meet standards. After installation, check the condition of the dust seal and pin to prevent dust ingress and pin bending, which could lead to premature bushing failure.