The Standard for Metric Precision Engineering
The Timken JM511945 cone is a cornerstone of the modern "Metric Series" tapered roller bearing family. Unlike the legacy Imperial designs such as the 462 series, the JM511945 is designed strictly to ISO standards, featuring a 65mm bore that integrates seamlessly with precision ground shafts found in European and Japanese machinery.
Nomenclature Decoding: "JM" Series
The prefix "JM" is not arbitrary. In Timken's ISO nomenclature, "J" indicates a Metric dimension, while "M" signifies a Medium Duty load rating relative to the bearing's cross-section. This balance makes the JM511945/10 set ideal for applications where space is constrained but high radial loads are present, such as in the output shafts of helical gear reducers or the wheel hubs of medium-duty commercial trucks.
Performance Characteristics
With a dynamic load rating ($C_1$) of approximately 148 kN, this bearing punches above its weight class. The K-Factor of 1.76 indicates a steep contact angle optimization, allowing it to handle substantial thrust loads. This is crucial for applications involving bevel gears where axial forces are significant. Compared to standard ball bearings like the SKF 6318, the JM511945 offers significantly higher rigidity and load-carrying capacity, albeit at slightly lower limiting speeds.
Global Interchangeability
One of the strengths of the metric series is universal interchangeability. A Timken JM511945 can physically replace an NTN or KOYO equivalent in the same series. However, mixing brands (e.g., a Timken Cone with a Koyo Cup) is strongly discouraged due to micro-variations in the raceway profiles and steel metallurgy, which can lead to premature spalling.
Application Sectors
We frequently ship these units for:
- Agricultural Machinery: Tractor transaxles and PTO drives.
- Construction: Concrete mixer drum rollers.
- Industrial Gearboxes: Intermediate shafts in conveyor drives.
Check our Heavy Duty Metric Catalog if your application requires even higher load ratings.