CAT 536-2601 BUSHING-SEM

CAT 536-2601 is a Caterpillar SEM (Special Engineering Material) bushing, adapted for the boom/stick hinge points of Cat 320D2, 323D2 and other excavators. It is used to withstand heavy swing and impact loads, reduce friction and wear between the pin and the hole, and improve the reliability and operating accuracy of the mechanism (Cat® Parts). The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 536-2601, Type SEM Bimetallic Bushing (Steel Back + Bronze Alloy Layer), Material Steel Back Q345B (Quenched and Tempered HRC28-32), Surface Sintered CuSn10 Bronze Alloy (Thickness 2.0 mm, Hardness HB90-110), Single Weight Approx. 1.6 kg, Operating Temperature -40℃ to +150℃, Rated Dynamic Load 95 kN, Rated Static Load 220 kN, Fatigue Life ≥7000 Hours

Key Dimensions
Inner Diameter 60.0 mm (Tolerance 0/+0.018 mm), Outer Diameter 75.0 mm (Tolerance 0/-0.022 mm), Length 50.0 mm (Tolerance ±0.12 mm), Alloy Layer Thickness 2.0 mm (Tolerance ±0.10 mm), Radial Clearance 0.03-0.05 mm, end face runout ≤0.04 mm, inner hole surface roughness Ra≤0.8 μm

Compatible Models and Parts: Compatible with Cat 320D2, 323D2, and 326D2 tracked excavators, used in the boom lower hinge point and stick cylinder connecting rod, with matching pin model 154-7892. It withstands reciprocating swing and impact loads, protects the hinge point hole wall, and reduces maintenance frequency.

Performance Parameters: Coefficient of friction ≤0.08 (unlubricated condition), ≤0.015 (lubricated condition), impact load resistance ≥160 kN, corrosion resistance meets ISO 9227 standard (no rust after 72 hours), steel backing and alloy layer bonding strength ≥150 MPa, compatible with lithium-based grease/molybdenum disulfide grease.

Structural and Performance Advantages: Bimetallic composite structure: The steel backing ensures high strength and rigidity, while the bronze alloy layer provides excellent wear resistance and self-lubrication, suitable for heavy-duty and impact conditions, reducing the risk of fracture and deformation in Cat® Parts.

High-precision dimensional control: Strict tolerances and low surface roughness ensure a perfect fit with the pin/hole, reducing clearance and vibration, and improving the mechanism’s operational accuracy and response speed.

Self-lubricating compatibility: The bronze alloy layer can store grease, providing short-term protection to the hinge points even when lubrication is interrupted, adapting to the lubrication and maintenance needs of complex on-site conditions.

Standardized design: Universal dimensions and installation interfaces require no additional machining, allowing for quick replacement and reducing maintenance time and costs.

Installation and maintenance points: Before installation, clean the bushing mounting holes and pins, checking for burrs and cracks; use a special press to cold press the bushing into the hole (interference 0.04-0.06 mm), ensuring coaxiality ≤0.06 mm. Welding or hot fitting is prohibited to avoid damage to the alloy layer.

After installation, apply Cat Moly-Dee grease, check that the bushing rotates freely without jamming, and tighten the pin fixing bolts to the main unit’s specified torque (approximately 200 N·m). Run for 10 minutes to confirm there is no abnormal noise or temperature rise.

Maintenance: Check the hinge gap every 500 hours. If the gap is >0.20 mm or the alloy layer shows peeling or scratches, replace immediately. Use original parts first to ensure compatibility and service life.