CAT 4T-0172 Angling Blade Trunnion

The CAT 4T-0172 is a Caterpillar original equipment bulldozer blade suspension trunnion (blade rocker arm/push beam hinge shaft), used to connect the bulldozer C-frame and push arm, enabling blade pitch and swing. The following is pure original data and does not include information on replacement parts.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model: 4T-0172; Type: Bulldozer blade suspension trunnion (solid alloy structure); Material: 42CrMo low alloy tempered steel (tempered hardness HB 280-320); Single weight: 6.18 kg; Operating temperature: -40℃ to +120℃; Rated static load: 850 kN; Rated dynamic load: 520 kN; Surface treatment: Nitriding + shot peening (nitriding layer depth 0.3-0.5 mm, surface hardness HV 650-750); Fatigue life: ≥5×10⁵ cycles; Corrosion resistance: IP65; Suitable impact load: ≤1200 kN

Key Dimensions
Ball head diameter: 127 mm (5.000 in, tolerance ±0.05 mm); Cylindrical journal diameter: 95 mm (3.740 in, h6 tolerance 0/-0.030 mm); Total length: 285 mm (11.220 in), journal length 150 mm, mounting hole diameter 28 mm (1.102 in, H7 tolerance + 0.030/0 mm), ball end sphericity ≤0.02 mm, coaxiality ≤0.03 mm, threads at both ends M24×2 (6g tolerance), effective thread depth 30 mm, chamfer 2×45°. Compatible Models and Parts: Compatible with the blade suspension system (C-frame and push arm hinge point) of Cat D4H bulldozers, 2 pieces per unit (1 on each side), paired with 4T-1753 bulldozer trunnion assembly and 8E-2305 working device linkage assembly, used to transmit pusher force and compensate for installation errors, compatible with the original manufacturer’s blade hydraulic control system.

Performance Parameters: Tensile strength ≥1080 MPa, yield strength ≥930 MPa, elongation ≥12%, impact toughness ≥60. J/cm² (-20℃), surface roughness Ra 0.8 μm (ball end), Ra 1.6 μm (journal), rotational oscillation angle ±15°, maximum oscillation frequency 1.2 Hz, wear rate ≤0.003 mm/1000 hours, assembly clearance 0.15-0.25 mm

Structural and Performance Advantages

High-strength Alloy Material: 42CrMo tempered steel provides high rigidity and impact resistance. Nitriding treatment enhances surface wear resistance and fatigue strength, suitable for heavy-duty bulldozer operations.

Precision Spherical Design: Ball end sphericity ≤0.02 mm, ensuring flexible blade oscillation, reducing friction and jamming at hinges, and improving work efficiency.

Threaded Connection Fixing: M24×2 threads ensure secure installation. Nitriding and shot peening treatment extend service life and reduce maintenance frequency.

Installation and Maintenance Points (Original Data)

Installation: Clean the mounting surface and journal (free from oil and burrs). Assemble in a cold state (heat assembly is prohibited; temperatures > 80℃ will affect the tempering structure). Pre-tighten bolts to 280 N·m. After installation, ensure the ball joint swings smoothly without jamming; radial runout ≤ 0.05 mm. Check the hinge clearance (0.15-0.25 mm) and ensure no interference in the hydraulic lines.

Maintenance: Add lithium-based grease (Cat DEO specific) every 500 hours. Check the swing flexibility every 1000 hours (swing resistance ≤ 500 N). Check ball joint wear every 1500 hours (replace if wear > 0.3 mm). Avoid overloading (≤ 120% of rated load) and prevent trunnion bending or breakage.

Troubleshooting: Swinging and jamming are often caused by insufficient lubrication or ball joint wear, requiring the addition of grease or replacement of the trunnion; abnormal noises are often caused by excessive hinge clearance, requiring adjustment of the clearance or replacement of the bushing; breakage is often caused by overload or material fatigue, requiring investigation of the operating conditions and replacement with original parts.