Deep Groove Ball Bearings SKF 6318 /C4

The SKF 6318 /C4 deep-groove ball bearing, measuring 90x190x43 mm and featuring significantly increased clearance, ensures reliable operation under thermal expansion.

The SKF 6318 /C4 single-row deep groove ball bearing accommodates radial and moderate axial loads in both directions. Manufactured from standard 100Cr6 rolling-element bearing steel, this open bearing features a sheet steel cage. This design has neither seals nor cover plates, allowing lubricants to reach the rolling elements unimpeded. With dimensions of a 90 mm bore, 190 mm outer diameter and 43 mm width, the design is suitable for industrial applications with continuous oil lubrication or a defined grease supply.

In which operating conditions does the 6318/C4 deep-groove ball bearing prove its worth?

This design is particularly suitable for use where there are significant temperature differences between the inner ring and the outer ring. Thanks to its open design, the component can be integrated directly into existing lubrication circuits or relubricated as required. Thanks to its specification in tolerance class P0/PN (ABEC 1), the rolling bearing is designed for a temperature range of –20 to +150 degrees. Designs with fixed fits on the shaft benefit from the increased radial flexibility.

What does the increased C4 clearance mean for this deep-groove ball bearing?

The designation C4 indicates a significantly increased radial clearance compared with standard clearance and the C3 grade. This characteristic compensates for the expansion of the inner ring caused by tight press fits, as well as for operational thermal expansion of the shaft. Without sufficient initial clearance, the operating clearance would shrink too much when the bearing is warm, which could lead to increased friction. Before installation, it should be checked whether operating temperatures and fit selections require this increased bearing clearance.