CAT 168-8390 Inner Race Cylindrical Roller Bearing

CAT 168-8390 is a Caterpillar single-row tapered roller bearing housing (outer ring) used in transmission/hydraulic systems. It is compatible with bearings such as 159-5424 and is used in C13/C15 engines, 349D2 excavator slewing gearboxes, 992K loader gearboxes, etc. It serves to provide radial positioning and load transfer, limit radial movement of the shaft system, and work with the inner ring and roller assembly to ensure stable operation of the bearing system. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 168-8390, bearing housing ring (outer ring of tapered roller bearing), material is high carbon chromium bearing steel GCr15 (hardness after quenching HRC60-64, outer ring raceway surface ultra-fine ground Ra≤0.08μm, wear-resistant, fatigue-resistant, pitting-resistant), single weight approximately 1.5 kg, operating temperature -40℃ to +120℃, suitable for high-speed (≤3000 rpm), medium and heavy load conditions, used in conjunction with 159-5424 bearing inner ring and roller assembly

Key Dimensions
Inner diameter 100 mm (fitting inner ring, tolerance 0/-0.025 mm), outer diameter 180 mm (tolerance +0.035/0 mm), width 46 mm (tolerance 0/-0.15 mm), raceway cone angle 12°30′, outer ring fit tolerance J7 (+0.015/-0.010 mm), radial clearance matching 0.025-0.050 mm, end face runout ≤0.02 mm, raceway roundness ≤0.005 mm
Compatible Models and Parts: Compatible with Cat C13/C15 engines (crankshaft bearing housing ring), 349D2 excavators (slewing gearbox output shaft bearing outer ring), 992K loaders (gearbox input shaft bearing housing ring), D11T bulldozers (final drive gearbox bearing outer ring), matching 159-5424 inner ring, 1J-0581 bearing cap, 474-9675 O-ring
Performance Specifications: Rated radial dynamic load matching 185 kN (matching 159-5424 inner ring), rated radial static load matching 250 kN, limiting speed (grease lubrication) 2800 rpm, (oil lubrication) 3600 rpm rpm, impact load ≥50 kN, service life ≥8000 hours (normal operating conditions)

Installation and Maintenance Points:
**Before installation, clean the raceway of the bearing race and the bearing housing bore, checking for cracks, rust, and raceway spalling. Measure the outer diameter of the bearing race and the inner diameter of the bearing housing bore to ensure the fit tolerances meet J7 standards.** Apply Cat-specific assembly oil to the bearing housing bore and use cold-press installation to avoid deformation of the bearing race due to heat fitting.

Use a special press to apply even pressure to press the bearing race into the bearing housing bore. Do not strike the end face of the bearing race to prevent damage to the bearing steel. After installation, check the fit between the bearing race and the bearing housing bore to ensure there is no looseness or gap. Adjust the radial clearance to 0.025-0.050 mm.

Maintenance and Replacement: Check the wear and surface roughness of the bearing race race every 1500 hours. If pitting, spalling, or radial clearance >0.15 mm is observed on the raceway, replace immediately. It is recommended to replace the bearing race simultaneously with the inner ring, roller assembly, and bearing cap to ensure the overall performance of the bearing system.