Ball bearing table

The tolerances for inner and outer diameters depend on the installation size. These are often approx. ±0.05mm to the nominal dimension. The bearing races are usually injection moulded and have a certain ovality by nature. For this reason, the caliper is used to measure 90° to the injection moulding point (if present) across the entire width of the bearing. The dimensions and tolerances are designed in such a way that they fulfil a light press fit by hand when using an H7 fixture and h6 shaft. An additional locating spigot using a circlip (shaft) and snap ring (housing) is recommended to prevent axial displacement.

The dimensions of ball bearings are usually specified in millimetres (mm). They comprise three main dimensions: The inner diameter, the outer diameter and the width of the bearing. These dimensions are crucial to ensure the compatibility of the bearing with the intended shaft and housing.

Inner diameter:

This is the diameter of the opening in the inner race of the bearing through which the shaft fits. This value is also known as the bore diameter. For example, a bearing could have an inner diameter of 10mm.

Outer diameter:

The outer diameter is the overall diameter of the bearing, measured from one outer edge to the opposite outer edge of the outer race. This value is important to ensure that the bearing fits into the housing. A typical example would be an outer diameter of 30mm.

Width:

The width of the bearing is the thickness of the entire bearing, measured from one side to the other. This dimension influences the stability and load capacity of the bearing. An example of this would be a width of 9mm.

The dimensions of a ball bearing are often given in the form "inner diameter × outer diameter × width". A bearing with the dimensions 10 × 30 × 9 therefore has an inner diameter of 10mm, an outer diameter of 30mm and a width of 9mm.

Serial numbers and suffixes:

Ball bearings often have serial numbers and suffixes that provide additional information about the bearing. The serial number provides information about the series and size of the bearing, while the suffix indicates details such as the type of seal or special design features. In contrast to metal bearings, we do not use suffixes at igus, as the open design offers the advantage that dirt and contamination can be easily rinsed out or removed with compressed air.

What does 6203 mean on a bearing, for example?

A typical serial number could be "6203"*. Here, "62" stands for the series (radial deep groove ball bearing) and "03" for the inner diameter of 17mm, as the bore code 03 corresponds to this inner diameter.

*igus product recommendation: Cost-effective all-rounder xirodur B180

Ball bearings are available in many different sizes and types, which vary depending on the application. The most common sizes range from small bearings with an inner diameter of 3mm to large bearings with an outer diameter of over 600mm.

Ball bearings are manufactured in different series and types, each with specific sizes and applications. For example, the 6000* and 6200* series are widely used and range in size from 10 × 30 × 9mm to 150 × 320 × 65mm. These bearings are used in many different industries, from the automotive industry to household appliances and sports equipment.

Special applications:

For special applications, there are miniature ball bearings with very small dimensions that are used in precision instruments and medical devices. On the other hand, there are also large ball bearings that are used in heavy machinery and industrial applications.

The wide variety of ball bearing sizes makes it possible to find the right bearing for every application and thus achieve optimum performance and durability.

*igus product recommendation: Cost-effective all-rounder xirodur B180

The DIN 625 standard specifies the dimensions and tolerances for radial deep groove ball bearings. It includes bearings with an inner diameter of 3mm to 1,500mm, an outer diameter of 10mm to 1,820mm and a width of 7mm to 140mm. This standardisation enables the compatibility and interchangeability of radial deep groove ball bearings.