

Design and Performance Characteristics
The performance characteristics of the 31309 bearing stem from the fundamental design of tapered roller bearings
.
Combined Load Capacity: The bearing can withstand combined radial loads(force perpendicular to the axis) and unidirectional axial loads(force along the axis) simultaneously, resulting in a high combined load-carrying capacity
. Its design incorporates a modified contact line between the rollers and raceways, which helps to reduce stress concentration .Separable Design: The bearing features a separable design, meaning the inner ring (including the rollers and cage) and the outer ring can be mounted separately
. This characteristic simplifies the installation and disassembly processes. Furthermore, it allows for the adjustment of the bearing's internal clearance after installation, which is crucial for optimizing system rigidity and controlling running accuracy .Material and Process: The bearing is typically manufactured from high-carbon chromium bearing steel (GCr15)
, and the cage is generally a pressed steel cage . Some models (e.g., FAG 31309-XL) are designated as "Extended Life" and may incorporate special heat treatment or design optimizations.





