Deep Groove Ball Bearings FAG 6405 -C3

The single-row FAG deep groove ball bearing 6405 -C3 (25x80x21 mm) offers reliable operation under thermal variations and at high speeds thanks to its increased bearing clearance.

The single-row deep-groove ball bearing 6405 -C3 from FAG is an open rolling bearing designed for demanding industrial shaft mountings. Manufactured from standard rolling-element bearing steel 100Cr6, the design primarily accommodates radial forces as well as axial forces in both directions. Thanks to its open design, lubricant from the gearbox housing or oil bath reaches the rolling elements and raceways unimpeded. The guided sheet steel cage maintains the balls at a uniform distance and ensures low-vibration operation across a temperature range of -30 to +120 degrees.

What is the 6405-C3 deep-groove ball bearing suitable for in mechanical engineering?

Typical applications include enclosed gearboxes or machine housings where lubrication is supplied from the outside and an external seal is fitted. Due to its open design without a flange or groove, the outer ring fits cylindrically into housing bores. This design is suitable for assemblies that operate in an oil circuit or where maintenance intervals require regular manual relubrication with a suitable rolling-element bearing grease.

What characterises the increased bearing clearance (C3) in this open bearing?

The designation C3 indicates a slightly increased radial bearing clearance compared with the standard version. This additional clearance between the rolling elements and raceways serves to compensate for thermal expansion when the inner and outer rings reach different temperatures during operation. Furthermore, the C3 clearance compensates for radial constrictions that occur with tight fits on the 25 mm shaft or in the 80 mm housing seat. In tolerance class P0/PN or ABEC 1, the component ensures precise shaft guidance without premature seizure.