Types of Rolling Bearings: A Comprehensive Guide

Importance of Bearings in Mechanical Systems

Rolling bearings are an important mechanical basic component used to support mechanical moving parts, carry loads and allow them to rotate, oscillate or reciprocate in a straight line. Rolling bearings require a higher degree of precision and reliability than general mechanical components. They are available in a wide range of different construction types. Specialized manufacturing plants usually mass-produce them due to their special manufacturing processes and high demand for finished product quality. This guide will focus on the common ways of categorizing rolling bearings. It will also introduce the basic concepts of spherical and linear rolling bearings, types of spherical plain bearings and classification methods for housed external spherical ball bearings.

Classification of Rolling Bearings

Rolling bearings have a wide variety of structural types, and there are many ways to categorize them. The more common rolling bearing classification method is based on the structure type and size of the bearing classification. Structure type classification is based on the direction of the load-bearing role, rolling body shape, each set of bearings in the number of rolling body columns, and work can be centering, and so on several aspects of classification, the name of the bearing is also the content of this to be integrated to name; size classification is based on the size of the bearing dimensions for type. The following is a specific introduction to the variety of rolling bearings.

Classification According to Load Direction And Contact Angle

• Radial bearings - rolling bearings are mainly used to bear radial loads, with the nominal contact angle from 0 ° to 45 °. The little contact angle is different but also divided into the following:

• Radial contact bearings - radial bearings with a little contact angle of 0°;

• Angular contact radial bearings - with little contact angles greater than 0° to 45°.

• Thrust bearings - rolling bearings are mainly used for axial loads with nominal contact angles greater than 45° to 90°. According to the different little contact angles, it is also divided into:

• Axial contact bearings-Thrust bearings with a nominal contact angle of 90°;

• Angular contact thrust bearings - with a nominal contact angle greater than 45° but less than 90°;

Classification According to The Type Of Rolling Body

• Ball bearings - the rolling elements are balls;

• Roller bearings - bearings in which the rolling bodies are rollers.

• Cylindrical roller bearings - bearings in which the rolling elements are cylindrical rollers;

• Needle roller bearings - bearings in which the rolling elements are needle rollers;

• Tapered roller bearings - bearings whose rolling elements are tapered rollers;

• Spherical roller bearings - bearings whose rolling elements are spherical rollers;

According to The Classification of Bearing Centering

• Spherical bearings - The raceway is spherical and can adapt to the two raceway axis lines between the angular deviation and angular motion of the bearing;

• Non-aligning bearings (rigid bearings) - bearings that can resist the angular deviation of the axis line between the raceways.

Classification According to The Number of Columns of The Rolling Elements of The Bearing

• Single-row bearings - with a row of rolling body bearings;

• Double row bearings - with two rows of rolling element bearings;

• Multi-row bearings - with more than two rows of moving elements and bear the same load-bearing direction. Such as three rows or four rows of bearings;

According to The Bearing, Parts Can Be Separated By Classification

• Separable bearings - bearings with detachable parts;

• Non-separable bearings- bearings in the final package, the rings can not be arbitrary free separation of bearings;

Classification According to The Shape of The Bearing Structure

Bearing according to its structure shape (such as with or without filling groove, with or without inner and outer rings and the form of the ring, the structure of the retaining edge, and even with or without cage, etc.) can also be divided into a variety of structural types.

Classification According to The Size of The Outer Diameter of The Bearing

• Miniature bearings - bearings with a nominal outside diameter of 26mm or less;

• Small bearings - bearings with a nominal outside diameter of 28 ~ 55mm;

• Small and medium-sized bearings - bearings with a small outer diameter of 60 ~ 115mm;

• Medium and large bearings - bearings with a small outside diameter of 120 to 190 mm;

• Large bearings - bearings with a small outer diameter of 200 ~ 430mm;

• Extra large bearings -bearings with a nominal outer diameter of 440mm or more;

Classification According to The Application Areas of Bearings

• General-purpose bearings - bearings used in general-purpose machinery or for general purposes;

• Specialized bearings-bearings used exclusively or mainly for specific hosts or special working conditions. Such as automobile bearings, railroad bearings, etc;

Classification According to Whether It Meets The Standard Size

• Standard bearings - bearings whose external dimensions conform to the provisions of the classic size series;

• Non-standard bearings - the external dimensions of any size do not meet the standard size series of bearings;

Classification According to Whether The Bearings Have Seals or Dust Caps

• Open bearings - bearings without dust caps and seals;

• Closed bearings - shafts with one or two dust caps, one or two seals, one dust cap and one seal;

Classification of Bearings According to The Unit of Expression of External Dimensions and Tolerances

• Metric bearings - external dimensions and tolerances using the metric (metric) unit of expression of the bearing;

• Inch bearings - bearings whose external dimensions and tolerances are expressed in imperial units;

Other Categories of Rolling Bearings

Classification of Housed Spherical Ball Bearings