CAT 296-1371 TRUNNION-GD

CAT 296-1371 is a Caterpillar standard load-bearing trunnion, adapted for the boom and stick hinge points of Cat 320D2, 323D2 and other tracked excavators. It is used to connect structural components and transmit loads, ensuring the swing accuracy and stability of the hinge points, and reducing wear and maintenance frequency (Cat® Parts). The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 296-1371, Type: Solid conventional load trunnion, Material: 42CrMo alloy structural steel (quenched and tempered HRC30-35), Single weight: approx. 12.8 kg, Operating temperature: -40℃ to +150℃, Rated dynamic load: 180 kN, Rated static load: 420 kN, Fatigue life: ≥8000 hours

Key Dimensions
Diameter: 70.0 mm (tolerance 0/-0.022 mm), Total length: 180.0 mm (tolerance ±0.15 mm), Shoulder diameter: 85.0 mm (tolerance 0/-0.030 mm), Shoulder thickness: 15.0 mm (tolerance ±0.10 mm), Center hole diameter: 12.0 mm (depth: 30.0 mm), Thread specification: M20×1.5 (length: 25.0 mm), Surface roughness: Ra≤0.8 μm
Compatible Models and Parts: Compatible with Cat 320D2, 323D2, and 326D2 tracked excavators. Used at the boom hinge point and the boom-stick connection hinge point. Matching bushings 536-2601 and pins 154-7892. Bears conventional swing and impact loads, transmits working force, and positions structural components.

Performance Parameters: Tensile strength ≥1080 MPa, Yield strength ≥930 MPa, Impact toughness ≥60 J/cm², Surface hardness HRC30-35, nitrided surface (nitriding layer depth 0.3-0.5 mm, hardness HV850-1000), excellent wear and corrosion resistance, compatible with lithium-based grease lubrication.

Structural and Performance Advantages: High-strength material: 42CrMo alloy structural steel, tempered and nitrided, possessing high tensile strength, yield strength, and impact toughness, suitable for swing and impact conditions under conventional loads, reducing the risk of fracture.

Precise Dimensions and Surface Treatment: Strict tolerance control ensures compatibility with bushings and pins. A nitrided layer enhances surface hardness and wear resistance, reducing hinge wear and extending service life.

Standardized Interface: Universal dimensions and mounting structure, requiring no additional machining, allowing for quick replacement and adaptability to various machine models, improving maintenance efficiency and reducing maintenance costs.

Reliable Positioning Function: Shoulder and thread design ensure axial positioning of the trunnion at the hinge point, preventing movement, ensuring mechanism accuracy, and reducing vibration and noise.

Installation and Maintenance Points: Before installation, clean the trunnion, bushing mounting holes, and pins, checking for burrs and cracks. Use a special press to cold press the bushing into the hole, then install the trunnion, ensuring coaxiality ≤0.06 mm and a tight shoulder fit. Welding or heat fitting is prohibited.

After installation, tighten the nut to 280 N·m with a torque wrench, apply Cat Moly-Dee grease, and test run for 15 minutes to confirm no jamming, abnormal noise, or abnormal temperature rise.

Maintenance: Check the hinge clearance every 800 hours. Replace immediately if the clearance is >0.25 mm or if there are scratches or wear >0.3 mm on the trunnion surface. Use original parts first to ensure compatibility and performance.