Caster wheels decrease wheel friction to allow more freedom of movement. They are made of different materials and come in many different sizes and bearing types. The bearing type can significantly increase the caster wheel’s performance and durability.

This article will review the advantages and disadvantages of the three bearing styles—ball, roller, and sleeve—and then discuss the most popular types of caster wheel bearings made from them.

Each type of caster wheel bearing has its own set of advantages. For example:

• Delrin® bearings are inexpensive and don’t require maintenance
• Roller wheel bearings are well suited to low-speed, intermittent, and manual operations.
• Precision caster wheel bearings are best when planned for low noise, high speeds, or continuous-operation environments
• Tapered caster wheel bearings are for the heaviest-duty applications

These are just four of the types and applications of caster wheel bearings that we talk about below. Read on to learn more about caster wheel bearings.

Pros and Cons of Ball, Roller, and Sleeve Bearings

Baller, roller, and sleeve bearings each have their advantages and disadvantages:

Ball Bearing Pros and Cons

Ball bearings generate less heat than other bearings due to a lower contact area. Lubrication is inexpensive and straightforward, needing only an oil bath, oil rings, or oil mist. Ball bearings are narrow and fit in compact housings. They can carry both thrust and radial loads. One need only stack them in tandem or in a back-to-back arrangement to increase thrust load capacity.

Roller Bearing Pros and Cons

Roller bearings lower friction resistance and power consumption. They are easy to install and have high mechanical efficiency. Suitable for mass production, roller bearings are stable and reliable with large loads and have a long lifespan.

Roller bearings can handle combined loads of radial and thrust simultaneously. However, they have a higher cost and create more noise. The bearing seat structure of roller bearings is more complex, and even when well lubricated and sealed, they will eventually fail due to rolling surface fatigue.

Sleeve Bearing Pros and Cons

Sleeve bearings are also called “bushings,” “plain bearings,” and “journal bearings.” They use a metal, plastic, or composite sleeve to improve movement between two parts. They have practically unlimited radial thrust capacity and are more expensive than ball bearings. Suitable for moderate to high-speed applications, sleeve bearings are stiffer than ball bearings. Their split halves are easier to install, inspect, and replace.

However, sleeve bearings do not have the capacity for axial thrust loads. They create higher friction and more heat than ball bearings or roller bearings, resulting in the need for more lubrication. However, they can reduce noise and absorb vibration, increasing the lifespan of both the wheel and the caster.

Types of Caster Wheel Bearings

When choosing the caster wheel bearings suited for your applications or industry, the first step is to check the type of wheel bearing currently used on the caster. Each type of bearing has advantages and disadvantages for different kinds of applications.

Annular Ball Bearings

Choose pre-assembled wheel-mounted annular ball caster bearings where maximum rolling ease and quiet operation are needed. These are precision-type bearings with machined, hardened raceways. They are best suited for light- to medium-duty loads. Annular ball bearings need no maintenance and can withstand temperatures up to 250oF. They have a side thrust loading rating of 20% radial capacity.

Bronze Bearings

Bronze caster bearings are made of a bronze metal alloy combined with other additives to eliminate porosity. They are corrosion-resistant and durable under a wide range of temperature and humidity conditions. Perfect for wet or high-heat applications, bronze caster bearings can withstand temperatures up to 525oF.

Caged (Torrington-Style) Roller Bearings

Torrington-style drawn cup roller bearings on 2” tread width wheels are ideal for maximum cage strength and long service life. Their steel cages provide inward retention of thrust, making them perfect for use in heavy-duty applications like tooling fixtures and towlines. Caged roller bearings require a spanner bushing or hardened shaft and tolerate temperatures up to 250oF.

Delrin® Bearings

Delrin caster wheel bearings consist of a DuPont-engineered plastic called acetyl resin (also known under the brand name Celcon®). They are durable, corrosion-resistant, and can withstand a wide range of temperature and humidity conditions. Wheels equipped with either one- or two-piece Delrin bearings are suited for applications with steam cleaning, brine conditions, or otherwise involving the presence of excessive water or liquids. Typical applications include material handling and food service.

Oilex Bearings

Oilex caster wheel bearings are best used where rolling ease is not a significant concern. They are manufactured using powder metallurgy to create tiny pores in bronze or iron alloy. The single-piece bearing is impregnated with an oil lubricant that bonds through sintering. Due to their self-lubricating capability, Oilex bearings rarely require maintenance and can withstand temperatures up to 450oF.

Pedestal Precision Ball Bearings

These are a form of sealed precision ball bearing with an integrated spanner bushing. Not recommended for heavy loads, pedestal precision ball bearings can withstand operating temperatures up to 250oF. They are best for ease of rolling and noise reduction in light- to medium-duty applications. They require no maintenance and are suited for 1-1/2” and 2” wheels with either 1-3/16” or 1-5/16” bores.

Plain Bore and Sleeve Bearings

Drastically different from the ball and roller bearings, plain bore caster wheel bearings used by themselves are only recommended when rolling ease is not essential. These maintenance-free, machine-bored wheels are suited for applications in which price is the dominating factor and are often used with either the axle or a spanner bushing resting directly on the wheel hub. 

Roller Bearings

Roller caster wheel bearings are the most popular anti-friction bearings for industrial equipment. They have a split metal outer cage holding the roller assembly and are not chemical- or water-resistant. Roller bearings can carry more oversized loads than the same diameter ball bearing and are often made of hardened and ground steel for maximum lifespan and load capability. Roller bearings can roll at speeds up to 2.5 mph and withstand temperatures up to 350oF.

Sealed Precision Ball Bearings

Sealed precision ball bearings include a two-piece approach of steel balls held by two lubricated, sealed, heat-treated raceways. They are top of the line in rolling ease and noise reduction and are the best option when high speed and high radial thrust capacity are needed. Commonly used in medium- and heavy-duty applications, sealed precision ball bearings require no maintenance and withstand temperatures up to 250oF.

Tapered (Timken®) Roller Bearings

Precision tapered roller bearings, also known as Timken® bearings, have a two-piece design that requires two paths and two washers per wheel. The dual raceways are machined to create a taper on the inner piece to create a “cup and cone” design. Tapered bearings are best for high-speed and high-load-weight applications, including industrial equipment and towlines, and require periodic inspection and adjustment. They are impact-resistant and can tolerate temperatures up to 400oF.

Rely on Caster Central for All of Your Caster Needs

Caster Central’s experienced staff has answers to all of your questions about caster wheel bearings, applications suitability, and material handling and storage solutions. We belong to the NCA and SCA and have been in business since 1866.

Caster Central offers expert design and installation services and works with all industries. We are a Tier One distributor for all of our suppliers and offer competitive and guaranteed pricing, just-in-time delivery, and no minimums. Call Caster Central today to discuss your needs at {PHONE NUMBER}.