Ball Bearings: What Do the Numbers Mean? Ball bearings are designed to provide smooth, low-friction movement in rotary applications. Used in drive systems, power tools, motors and more, ball bearings are identified by their numerical designation. This number typically provides important information about the bearing’s size, type, and design. In this guide, we explain what ball bearing numbers mean in easy-to-follow terms. Bearing Number Analysis Bearing numbers are typically composed of three parts. Consider a sample bearing number: 6203-2RS. This feature is shared across many bearing types, including roller bearings and linear bearings. Each section of the number offers insight into the important aspects of the bearing: 6203 This three-digit number is the most important section. It contains information on the type and size of the bearing. In the above example, the 6203 indicates a deep groove type bearing with a size designation of 17 mm bore x 40 mm OD x 12 mm width. This indicates that the bearing is 17 mm inside diameter, 40 mm outside diameter and 12 mm width.
2RS This two-digit number indicates the bearing type, specifically whether it is open, shielded or in contact. RS stands for a rubber seal on either side of the bearing. These are commonly used to keep out dirt and debris and can help extend the life of the bearing. In this case, the bearing has two rubber seals. Bearing Identification When selecting a new bearing, you should refer to the bearing’s dimensional charts to ensure you are selecting the correct size and type. In most cases, it is best to refer to the bearing by its official designation (e.g. 6203-2RS). This is typically the case when selecting replacement bearings for existing equipment. However, when designing a new application, you may also refer to a CAD model of the bearing you intend to use. This is a more straightforward way to make sure you select the correct bearing type. Benefits of Ball Bearings With their useful design, ball bearings offer advantages over other bearing types. These include: • Lower friction: Ball bearings are designed to reduce friction, allowing the load in an application to rotate freely. • Durability: The components of a ball bearing are separated, which prevents them from being damaged by direct contact. This also helps lubricants remain in place longer, improving the bearing’s performance. • Precise control:The bearings’ precision construction makes it easier to control the load in an application. • Lower maintenance: Compared to roller and sleeve bearings, ball bearings require less maintenance, helping to reduce operating costs.
Final Thought Ball bearings are popular components in mechanical drive systems. They are available in a wide range of sizes and styles, and can be identified by the numbers on their designation. Understanding how to read these numbers can make it easier to select the correct bearing for your application. It also helps to understand the critical benefits of ball bearings, including durability and low friction. With these pieces of information you can be sure to get the best performance and longest life from your mechanical drive system.
