The Tapered Roller Bearing: Advantages and Uses
The tapered roller bearing is essential in many applications and industries, including heavy machinery, automotive, and aerospace.
An adequately maintained tapered roller bearing can provide reliable performance for extended periods without failing. The bearing’s durability and longevity can be enhanced by incorporating high-quality frame wear parts such as seals, lubrication systems, and suitable housings. These additions allow tapered roller bearings to withstand harsh operating conditions, reduce downtime, and lower maintenance costs.
What are Tapered Roller Bearings?
Tapered roller bearings consist of outer and inner rings that house rolling elements. These rollers taper right into truncated conical shapes. The cone is the inner ring, while a cup serves as the outer ring, a cage, and rollers. Both inner and outer ring raceways taper to accommodate the rollers’ shape.
Features of Tapered Roller Bearings
The window cage, inner ring, and tapered rollers forming the cone are in one piece and can generally be mounted separately from the outer ring.
The tapered angle enables tapered roller bearings to support large radial and axial loads in one direction. Using an opposing second bearing often requires axial guidance in the other direction. The axis of the bearing as well as the angle, determines the ratio between the radial capacity and the axial capacity.
Tapered roller bearings must be serviced occasionally with oil or grease. This is because they can be used in various environments ranging from –30 degrees Celsius to +120 degrees Celsius. Breakage can occur if the tapered roller bearings function in extreme temperatures.
Types of Tapered Roller Bearings
Several models of tapered roller bearings exist today, though most bear great similarities. Nevertheless, every roller bearing has significant features different from the others.
For instance, the single-row tapered roller bearing model is the most frequently used – and simplest – tapered roller bearing. This tapered roller bearing is often mounted in pairs and generally consists of a cup and a cone. Variants of the single-row tapered roller bearing exist, the most popular of which is the model with the cup provided with a collar in order to facilitate axial positioning.
Another well-known model is the two-row tapered roller bearing which consists of 2 cups and a double cone. The configuration of this particular bearing type ensures a considerable effective separation.
Uses of Tapered Roller Bearings
Tapered roller bearings are usually appropriate where a bearing must handle a combination of loads. One of the most popular uses of tapered roller bearings involves maintaining axial balance. This is often achieved using multiple tapered roller bearings along a shaft or axle.
The tapered roller bearings evenly distribute loads when adequately aligned. This significantly minimizes wear and tear on the components. Since tapered roller bearings have a higher surface area, they effectively distribute heat and friction from combination loads than non-tapered roller bearings.
The only way non-tapered rollers are more efficient than their tapered counterparts is due to their straightforward non-combination forces. The minimized friction boosts the rotational speed of interfacing components, making tapered roller bearings perfect for use in the following:
- Motors
- Wheels and axles
- Engines
- Propellers and turbines
- Gearboxes, especially those equipped with helical gears, etc.
The Advantages of Tapered Roller Bearings
Using tapered roller bearings has several advantages. Here are a few of them, highlighted in no particular order:
Tapered Roller Bearings Support Axial and Radial Loads
A tapered roller bearing can support axial and radial loads when other bearing types are primarily designed to support one type of load. Regardless of whether the load on the bearing is axial, radial, or a combination of both, the tapered design gives rise to a resultant force that pushes or propels the rollers up the taper towards the rib or flange of the cone.
This particular force seats the rollers against the flange while maintaining roller alignment. Engineers usually design systems using tapered roller bearings in opposing pairs. This is to ensure that axial forces are equally supported in both directions.
Supports Higher Load-Carrying Capacities
Tapered roller bearings can support higher load-carrying capacities, especially when compared to ball bearings of the same magnitude or size. Line contact between every raceway and roller provides a much wider weight-bearing surface than a ball’s point of contact.
Therefore, a tapered roller bearing for an identical load capacity will be much smaller than a ball bearing.
Adjustable Clearance
Another significant advantage of tapered roller bearings is their adjustable clearance. The cone and cup assembly are detachable, allowing axial clearance, end play, axial interference, or preload by moving the cone or cup axially during installation.
In several applications, slight preloads maximize bearing overall performance and life. However, excessive preloads generate higher temperatures – or drastically reduce bearing life – leading quickly to bearing failure.
High Reliability
Tapered roller bearings are much more reliable when utilized appropriately than their non-tapered counterparts or other bearing types. Automobiles can function for hundreds of thousands of miles without undergoing tapered bearing failures and requiring little or no maintenance.
Minimum Load Requirement
Tapered roller bearings are far more unlikely to skid or slide when unloaded or loaded. But other roller bearings have minimal load requirements – i.e., a highly consistent amount of pressure that must be carefully maintained – to prevent the rollers from sliding in their raceways.
Tapered Roller Bearings Help Extend Equipment Lifespan
Standard bearings generally break down much more quickly in high-speed applications and severely damage the components they interface with. However, tapered roller bearings combine less friction with high surface-area contact with high-speed rotating components.
The outcome is a highly efficient transfer of shifting and combined forces into a single rotational axis. This remarkable efficiency translates to less vibration, which helps prevent damage to delicate components throughout the equipment. This also minimizes the need to dampen external forces.
Conclusion
Tapered roller bearings are commonly used in several heavy-duty, moderate-speed applications with multi-directional loading. Gear sets and gearboxes, especially those employing helical gears, use tapered roller bearings due to multi-directional loading and excellent performance.
Mounted tapered roller bearings are common with aggregate and mining equipment, agricultural machinery, fans exposed to high axial forces, etc.