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Roller Bearing vs. Ball Bearing: What's the Difference?

The smallest elements can sometimes make the biggest impact when using furniture and equipment in different commercial and industrial environments. For instance, roller and ball bearings in caster wheels make transporting heavy items across multiple surface types easy. Though it might appear as though these bearings are the same, they're vastly different and suitable for specific applications.

Which is best in the roller bearing vs. ball bearing debate? Our team at Caster Central has decades of experience producing many kinds of caster bearings and knows how confusing it can be to determine which bearing type is ideal for a specific application. Get clarity about the similarities and differences between roller and ball bearings in our guide below. 

Don't hesitate to contact us if you need a specific caster bearing type for your business equipment. 

What Are Ball Bearings?

Before going into a roller bearing vs. ball bearing discussion, you should know what both mechanical bearings are to fully comprehend their differences and applications. 

Industrial ball bearings have outer and inner rings with a series of steel balls and a cage to ensure even spacing between the balls inside the rings. Both rings could be steel, ceramic, or another durable material designed to withstand heavy loads and high speeds in material handling applications. 

The balls inside the bearing create low-friction contact points with the outer and inner rings. As a result, the bearing can move without much resistance or energy consumption. In other words, the ball bearing design makes it easy for items to glide over a surface with even load distribution.

Typical applications for ball bearings are:

  • Electric motors
  • Car engines
  • Power tools
  • High-speed tooling equipment

Pros and Cons of Ball Bearings

Ball bearings offer incredible versatility since they can move on more than one axis. They can accommodate applications with pure radial loads like gearboxes and machine shafts, pure axial or thrust loads like industrial conveyor and screw drive systems, or any load combination. 

Ball bearings don't produce much friction because they don't have a large contact area for the load. As a result, they're great for applications where smooth movements at higher speeds are necessary.

Unfortunately, the lack of surface area makes ball bearings unsuitable for heavy loads. They function best in applications that require light loads and speed. 

Types of Ball Bearings

Ball bearings can have a single or double row, but the former is more common than the latter. Both options have a series of balls between an inner and outer ring with a cage separating them. However, the single-row ball bearings have one row of steel balls moving along one grooved path, while the double-row ball bearings have two sets of balls and dual raceways.

The Conrad type of ball bearing is a radial ball bearing with a unique design that allows more balls to fit between the rings by creating a filling slot cut through the bearing's shoulder into its ball grooves. Including extra balls in this design increases the load capacity of the bearing.

What Are Roller Bearings?

When considering that roller bearings also create smooth movements like ball bearings, the roller bearing vs. ball bearing discussion might seem unnecessary. However, industrial roller bearings don't use a set of durable balls to facilitate motion. Instead, they use cylindrical rollers to reduce friction between the bearings and whatever surface they encounter. 

The rolling element of this bearing sits between the inner and outer rings. Because of the size and nature of the cylindrical roller, it has a greater contact surface area. Like ball bearings, the cylindrical rollers have even spacing with a cage to maintain their positioning. 

This design gives roller bearings an excellent load capacity with improved radial and axial performance. You'd usually find these bearings in applications and industries like:

  • Agricultural equipment
  • Mining
  • Construction

Pros and Cons of Roller Bearings

Roller bearings don't have to be cylindrical. They're also available in other forms like spherical, needle, and tapered shapes to work in more applications.

With the increased surface area, the rollers can support heavier radial loads. Roller bearings also offer exceptional durability, so there's little to no worry about heavy loads damaging them. However, they're bigger, so they're best for machinery and equipment with enough space to accommodate them.

A downside to using industrial roller bearings is friction. Roller bearings take on a little more friction than ball bearings despite their limited movements with radial loads. The extra friction may require additional maintenance to keep the roller bearings in good condition and prevent the need for premature replacement.

Types of Roller Bearings

Roller bearings come in many forms, like spherical roller bearings. These bearings feature two rows of barrel-shaped rollers on a spherical raceway within the outer ring. This type of bearing is good for carrying heavy loads. 

Cylindrical roller bearings have rolling elements that resemble tubes and move with guidance from flanges on the other or inner ring. The bearing is suitable for relatively high speeds since the cylindrical elements inside the bearing don't produce much friction. It's common to find cylindrical roller bearings working alongside angular contact ball bearings in machine spindles.

As a variant of cylindrical roller bearings, needle bearings have long rollers that are smaller in diameter in relation to their length. The increase in surface area in contact with the raceways means these rollers can accommodate a greater load capacity without needing more clearance between the bearing's axle and the rest of the structure.

Another common type of roller bearing is the tapered variety. With tapered roller bearings, each rolling element has one end that's smaller than the other. As a result, the outer ring has a slightly curved design to prevent edge loading on the rollers. Tapered roller bearings can manage pure axial load applications at moderate speed. 

The Difference Between Roller and Ball Bearings

If you need bearings for an application that demands speed but doesn't have a heavy load, ball bearings are likely the best choice. On the other hand, roller bearings are best for heavy-duty applications with shocks. 

Manufacturers frequently sell ball bearings as assemblies. When it's time to replace them, you'd need to replace the unit, not individual parts. Roller bearings are different; you can replace the inner and outer rings individually if necessary. 

Because ball bearings are versatile, the single-row bearing style is the standard. You can use them in various applications regardless of manufacturers. However, roller bearings don't have a specific standard, so particular applications will require a specific bearing brand, type, size, and so on.

Another difference between ball and roller bearings is the possibility of usage following the misalignment of a roller element. For example, ball bearings could still work if a ball has an angular misalignment up to 0.004 inches between the bearing and the shaft. Roller bearing misalignments are less forgiving and could stop functioning correctly if a roller falls too far out of place.

Get the Caster Bearings You Need From Caster Central 

No matter your thoughts regarding the roller bearing vs. ball bearing discussion, Caster Central is the go-to destination to acquire either. We offer a wide range of wheel and material handling products and accessories, from cylindrical roller bearings to various mount types of caster wheels

Caster Central has over 150 years of experience as an industry leader. We provide caster bearing solutions for any personal, commercial, or industrial use and back our products and services with a 100% satisfaction guarantee. Our knowledgeable and well-trained team is ready to help you in any way. Call (800) 445-4082 today to inquire about our Caster Central products.