KOYO HICAP30304AJR Tapered Roller Bearing

The KOYO HICAP30304AJR is a premium, heavy-duty tapered roller bearing. KOYO's 'Hi-Cap' technology features optimized internal geometry and an advanced surface hardening process that increases dynamic load capacity and significantly reduces rolling resistance, even under extreme load conditions.

Technical Specifications

• Manufacturer: KOYO
• Part Number (SKU): HICAP30304AJR
• Bearing Type: Single-row tapered roller bearing
• Bore Diameter (Inner Diameter, d): 20 mm
• Outer Diameter (D): 52 mm
• Total Width (T): 16.25 mm
• Inner Ring Width (B): 15 mm
• Outer Ring Width (C): 12 mm
• Material Quality: High-purity, heat-treated chromium-alloy bearing steel
• Design Characteristic: High-capacity design (Hi-Cap), precision cage construction

Functional Operation and Significance

The primary function of tapered roller bearings is to provide rigid, precise guidance for rotating shafts and to minimize mechanical friction. Due to their geometric configuration, they absorb combined radial and unidirectional axial forces with outstanding efficiency. In automotive and mechanical drivetrains—such as differentials, manual and automatic transmissions, wheel hubs, and transfer cases—they are essential for maintaining accurate gear engagement clearances and ensuring smooth, quiet operation.

Typical Symptoms of Wear and Failure

Insufficient lubrication, ingress of contaminants, or natural material fatigue can lead to bearing failure over time. Common symptoms of failure include:

• Speed-dependent mechanical humming, growling, or whining noise that varies under load.
• Increased radial or axial shaft clearance and play within the assembly.
• Elevated operating temperature around the bearing housing.
• Abnormal vibration and erratic rotation caused by pitting or spalling on the raceway surfaces.