Bearings play a critical role in ensuring smooth motion and long service life in machinery. One of the most important factors when selecting the right bearing is understanding the type of load it must support. The two primary load types are radial load and axial load. Choosing a bearing without properly considering these loads can lead to premature failure, excessive wear, and costly downtime.
This blog explains the difference between radial and axial loads, how they affect bearing performance, and how to choose the right bearing for your application.
What Is a Radial Load?
A radial load acts perpendicular (at 90°) to the shaft axis. In simple terms, it is a load that pushes sideways on the bearing.
Common Examples of Radial Load:
- Weight of rotating shafts
- Belt and pulley systems
- Gear-driven applications
- Electric motors
Bearings Suitable for Radial Loads:
- Deep Groove Ball Bearings
- Cylindrical Roller Bearings
- Needle Roller Bearings
Radial-load bearings are designed to handle high rotational speeds while supporting significant side forces.
What Is an Axial Load?
An axial load acts parallel to the shaft axis, pushing or pulling the shaft along its length.
Common Examples of Axial Load:
- Thrust from helical gears
- Vertical shafts
- Pumps and compressors
- Screw and spindle applications
Bearings Suitable for Axial Loads:
- Thrust Ball Bearings
- Thrust Roller Bearings
- Angular Contact Ball Bearings
Axial-load bearings are engineered to manage force in one or both axial directions while maintaining alignment.
Radial Load vs. Axial Load: Key Differences
| Feature | Radial Load | Axial Load |
|---|---|---|
| Direction | Perpendicular to shaft | Parallel to shaft |
| Force Type | Sideways force | Push/Pull force |
| Common Bearings | Deep groove, cylindrical | Thrust, angular contact |
| Speed Capability | High | Moderate to high (depends on bearing type) |
| Typical Use | Motors, gearboxes | Pumps, vertical shafts |
Combined Loads: When Both Act Together
In many real-world applications, bearings experience both radial and axial loads simultaneously. These are known as combined loads.For industry-standard bearing load definitions, refer to ISO bearing load guidelines or engineering resources such as SKF and NSK technical manuals
Bearings for Combined Loads:
- Angular Contact Ball Bearings
- Tapered Roller Bearings
- Spherical Roller Bearings
These bearings are specially designed to distribute forces evenly, ensuring stability, accuracy, and longer service life.
Why Load Understanding Matters
Incorrect load selection can cause:
- Overheating
- Excessive vibration
- Premature bearing failure
- Shaft misalignment
Understanding whether your application involves radial load, axial load, or both helps you:
- Choose the correct bearing type
- Improve machine efficiency
- Reduce maintenance costs
- Extend equipment life
How to Choose the Right Bearing
When selecting a bearing, consider:
- Load direction (radial, axial, or combined)
- Load magnitude
- Operating speed
- Mounting position
- Environmental conditions
Consulting a bearing expert ensures the best match for your machinery.
Conclusion
Understanding the difference between radial and axial loads is essential for selecting the right bearing and ensuring reliable machine performance. While radial loads act sideways and axial loads act along the shaft, many applications involve a combination of both. Choosing the correct bearing type based on load conditions leads to improved efficiency, durability, and uptime.
At Accurate Bearing, we help you select the right bearing for every load condition—ensuring precision, reliability, and long service life.