CAT 307-4155 BEARING ANGU

CAT 307-4155 (3074155) is a Caterpillar single-row angular contact ball bearing (non-four-point contact/tapered type), suitable for high-speed + complex load components such as gearbox spindles and hydraulic pump drive shafts in CAT loaders and excavators. It is used to withstand combined radial and unidirectional axial loads. The following is the core technical information:

Core Technical Parameters
Item Details
Part Model: CAT 307-4155 (3074155) Single-row angular contact ball bearing (suitable for high-speed complex loads, such as gearbox spindles and hydraulic pump drive shafts)

Core Materials: Inner ring/outer ring: SAE 52100 bearing-grade chromium steel, hardened to HRC 60–64; Balls: GCr15 chromium steel, surface Ra≤0.2 μm; Cage: Stamped low-carbon steel (brass optional for high-speed applications), anti-ball misalignment

Key Dimensions: Inner diameter 60 mm, outer diameter 110 mm, width 22 mm, contact angle… 25° (AC type), ball diameter 9.525 mm, 10 balls, radial clearance C3 (0.012–0.020 mm), journal tolerance h6 (0–-0.019 mm), bearing housing tolerance H7 (0–+0.030 mm)

Single weight: Approx. 0.68 kg (1.5 lb)

Compatible models: CAT 950M/966M loaders (gearbox spindle), 320GC excavators (hydraulic pump drive shaft), mini road rollers (vibratory wheel drive shaft), for high-speed rotating parts that need to withstand combined radial and axial loads.

Operating conditions: Dynamic radial load 58 kN, dynamic axial load 24 kN, limiting speed 6300 rpm (grease lubrication), operating temperature -30℃ to +120℃, compatible with extreme pressure lithium-based grease (NLGI 2)

Core functions and structural features: 25° Contact Angle Design: Balances radial and axial load capacity, suitable for medium-to-high speed and medium axial load conditions. It offers 30% higher axial load capacity than 15° contact angle bearings and better speed adaptability than 40° contact angle bearings.

Non-Separable Structure: The inner and outer rings are integrated, ensuring high coaxiality after installation, suitable for applications requiring high rotational precision (such as gearbox spindles).

C3 Clearance Fit: Compensates for temperature expansion during high-speed operation, preventing jamming, ensuring smooth rotation, and suppressing vibration and noise.

High-Precision Cage: The stamped steel cage precisely positions the steel balls, reducing friction and wear, and extending bearing life.

Installation and Maintenance Points
Installation Specifications: Clean the journal and bearing housing. The journal surface Ra≤0.8 μm, free of scratches; use a transition fit (clearance 0.001–0.006 mm) with the shaft and a clearance fit (clearance 0.002–0.010 mm) with the bearing housing. Install by evenly tapping the inner ring end face with a sleeve to avoid deformation of the outer ring due to stress. Ensure a tight fit with the shaft shoulder. After installation, axial movement should be ≤0.01 mm.

Add lithium-based grease, filling 1/3 of the bearing’s internal space to prevent heat buildup during high-speed operation.

Maintenance Recommendations: Every 800 operating hours, check for pitting and wear on the steel balls/raceways, and for abnormal noises during rotation. Replace immediately if radial clearance >0.03 mm.

Avoid confusion with similar models such as 307-4156. Verify the inner diameter/outer diameter/width. The inner diameter of 307-4155 is fixed at 60 mm.

For high-speed operation, pair installation (back-to-back DB or face-to-face DF configuration) is recommended to improve rigidity and resistance to overturning moments.