178-4640: Bearing – Cone(Debris Resistant)

CAT 178-4640 is a Caterpillar tapered roller bearing inner ring, suitable for heavy-duty equipment drive systems, used to withstand radial and unidirectional axial heavy loads. Key information is as follows:

Key Parameters
Item Details
Type: Tapered roller bearing inner ring (inner ring only, excluding outer ring, rollers, and cage), compatible with corresponding Cat tapered roller bearing assemblies, used for radial and axial load support in heavy-duty drive systems.
Dimensions (Metric/Imperial): Inner diameter 165.10mm (6.50in), outer diameter 200.00mm (7.87in), width 44.45mm (1.75in), compatible with corresponding journals and bearing assembly mounting space.
Material: Chromium-molybdenum alloy steel, quenched and tempered, hardness HRC60-64, surface ground and polished, roughness Ra≤0.4μm, fatigue-resistant, wear-resistant, suitable for heavy-duty impact conditions.
Accuracy: Inner diameter tolerance. ±0.01mm, outer diameter taper tolerance ≤0.005mm, width tolerance ±0.02mm, ensuring precise contact with the rollers and smooth operation of the bearing assembly.

Compatible Assemblies: Compatible with Cat 178-4641 tapered roller bearing assemblies. The inner ring and rollers have line contact, providing approximately 3 times the load-bearing capacity of ball bearings of the same size.

Suitable Applications: Suitable for drive axle main reducers, differentials, and gearbox output shafts in Cat 980G/980H loaders, D8T/D9T bulldozers, 777F mining dump trucks, and other equipment. Used to withstand heavy loads and impact loads in the transmission system, ensuring transmission efficiency and stability.

Suitable for replacing worn inner rings during equipment overhauls or bearing maintenance, eliminating the need to replace the entire bearing assembly and reducing maintenance costs.

Performance Characteristics: Made of chromium-molybdenum alloy steel, professionally heat-treated, with high fatigue strength. Lifespan is approximately 50% longer than ordinary carbon steel inner rings, suitable for the long-term operation requirements of heavy equipment. The high-precision conical surface design ensures linear contact with the rollers, resulting in uniform stress distribution, strong load-bearing capacity, and suitability for heavy-load, low-speed, and high-torque transmission conditions.

Surface grinding and polishing reduces frictional loss with the rollers, lowers operating temperature, and extends the service life of the bearing assembly.

Alternative Models: Direct replacements for 107-6643 and 8T-4170; interchangeable and suitable for the same bearing assemblies and installation conditions.