Koyo KOYO6318-ZZC3 Deep Groove Ball Bearing 90mm

Product Description

The KOYO KOYO6318-ZZC3 is a single-row, deep groove radial ball bearing built for applications where moderate contamination is a concern. The double metal shield (ZZ) configuration keeps grease in and contaminants out, making it suitable for environments where an open bearing would be exposed to dust or debris. The C3 internal clearance designation provides a looser-than-standard fit, accommodating thermal expansion and higher-speed operation. Licensed bearing technicians, millwrights, and HVAC equipment service professionals are the typical installers for bearings in this series.

This bearing is commonly used in industrial and commercial equipment including electric motors, blowers, fans, pumps, and HVAC air-handling units. The 63 series designation places it in a medium-duty load range appropriate for radial load applications found in both commercial mechanical systems and light industrial machinery. Its shielded design suits installations where periodic relubrication access is limited.

Key Features

• Double metal shield (ZZ) construction retains grease and resists moderate contamination
• C3 internal clearance rating accommodates thermal expansion and elevated operating temperatures
• Single-row deep groove design handles radial loads with low friction
• 63 series medium-duty load capacity suitable for motors, fans, and pumps
• Compatible with oil or grease lubrication systems

Compatibility

Designed as a direct replacement for 6318-ZZ C3 designation bearings used in single-row deep groove ball bearing applications across industrial motors, blowers, fans, and HVAC equipment requiring a 90mm bore.

Installation Notes

Bearing installation should be performed by a qualified millwright or mechanical technician. Always de-energize and lock out the equipment before removing or installing any bearing. Use a proper bearing press or induction heater when seating the bearing onto a shaft — never strike the bearing directly with a hammer, as this can damage the raceways and shielding. Verify housing bore and shaft tolerances before installation to maintain the intended C3 clearance.

Technical Specifications

• Series: 63
• Bore Diameter: 90mm
• Row Configuration: Single Row
• Bearing Type: Deep Groove Ball Bearing
• Shield Type: Double Metal Shield (ZZ)
• Internal Clearance: C3
• Lubrication: Grease or Oil

Standard Information

• Brand: KOYO
• Manufacturer Part Number: KOYO6318-ZZC3