CAT 188-5072 160mm Inner Diameter Pivot Bearing

CAT 188-5072 is a Caterpillar genuine double-row angular contact pivot bearing, suitable for the swing platform and boom hinge, and stick pivot of Cat 320D2/323D2 excavators. It is used to withstand combined loads and ensure the swing accuracy of components. The following is pure raw data and does not include replacement parts information.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model: 188-5072; Type: Double row angular contact ball bearing (with cage, seal, locating groove); Material: Outer/inner ring: Chromium bearing steel (GCr15); Rolling elements: Bearing steel balls (φ12 mm, 16 balls/row); Cage: Phenolic resin; Seal: Nitrile rubber (NBR); Weight: 3.2 kg; Applicable pivot diameter: φ100 mm; Rated radial load: ≥280 kN; Rated axial load: ≥150 kN; Limiting speed: 120 rpm (grease lubrication); Operating temperature: -30℃ to +120℃; Lubrication method: Grease lubrication (lithium-based grease, dropping point ≥190℃); Protection rating: IP66; Assembly clearance: 0.012-0.025 mm

Key Dimensions
Inner diameter: φ100 mm (tolerance +0.015/+0.005 mm); Outer diameter: φ140 mm (tolerance…) 0/-0.02 mm), width 42 mm (tolerance ±0.12 mm), positioning groove diameter φ130 mm (tolerance 0/-0.03 mm), groove width 5 mm (tolerance ±0.10 mm), ball diameter φ12 mm (tolerance ±0.005 mm), ball spacing 25 mm, clearance C3 group (0.015-0.028 mm), roundness ≤0.008 mm, cylindricity ≤0.010 mm
Performance parameters: outer ring hardness HRC 60-64, inner ring hardness HRC 60-64, rolling element hardness HRC 62-66, coefficient of friction ≤0.002 (grease lubrication), rated life ≥20000 hours (rated load cycles), sealing performance 0.3 MPa pressure no leakage, impact resistance ≥500 g (11 ms pulse), corrosion resistance neutral salt spray test ≥72 Rust-free operation for hours.
Structural and performance advantages:
Double-row angular contact design: Can withstand radial and bidirectional axial loads simultaneously, suitable for complex stress conditions at the pivot point, reducing bearing movement.

Integrated seal and cage: NBR seal cap prevents dust/moisture intrusion, phenolic resin cage ensures even distribution of steel balls, reducing friction and wear.

Positioning groove structure: Quickly positions with the pivot support, with a coaxiality error ≤0.02 mm after assembly, improving oscillation accuracy.

GCr15 bearing steel material: After quenching treatment, it balances hardness and toughness, suitable for high-frequency oscillation and impact loads.

Installation and Maintenance Points (Original Data)

Installation: Clean the pivot and bearing inner bore (free from oil, rust, and impurities). Assemble using the cold pressing method (pressing force ≤ 80 kN, indenter coaxiality ≤ 0.015 mm). Ensure proper fit between the locating groove and the support locating pin (clearance ≤ 0.03 mm). Do not heat (temperature > 80℃ can easily cause bearing deformation). After assembly, check the radial clearance to be 0.015-0.028 mm.

Maintenance: Replenish with lithium-based grease every 800 hours (use 1/2 of the bearing cavity volume). Check the clearance every 1500 hours (replace if it exceeds 0.05 mm). Check the seal every 2500 hours (replace the seal if leakage occurs). Avoid uneven loading (uneven load ≤ 10% of rated load). Prevent foreign objects from entering the bearing clearance.

Troubleshooting: Excessive clearance is mostly due to wear; replace the bearing. Abnormal noise is mostly due to insufficient lubrication or damage to the steel balls; add grease or replace the bearing. Leakage is mostly due to aging of the seal; replace the seal and clean the bearing cavity.