Deep groove ball bearings are the most widely used among all bearings. They can support both a radial load and a certain amount of axial load coming from both directions at the same time. If a bearing to support a very large axial load is needed, the "angular contact ball bearings" explained below are used.

Radial roller bearings are roller bearings that can support a force perpendicular to the shaft. They can support an even greater load than radial ball bearings, and there are bearing types that are made to suit the type of roller.

Means "increased internal clearance". Often referred to as high-speed, this means that the bearing is designed for high rotational speeds and moderately high temperatures. CAUTION: a bearing with increased internal clearance will not operate optimally at low speeds. Please refer to the data sheet for the bearing you are looking for to find out its rotation speed limit.

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The Deep Groove Ball Bearing, known as 6306-32-2RS-C4-KOYO JTEKT, has an inner diameter of 32 mm, an outer diameter of 72 mm and a thickness of 19 mm.

These suffixes mean "with 1 or 2 sheet metal deflectors", for dust-tightness. At 123Roulement, we specify whether the bearing is sealed on 2 sides with "ZZ".

These use barrel-shaped convex rollers as their rolling elements. As shown in Figure 7, they are inserted between a spherical outer ring raceway surface and an inner ring raceway surface. This is why the inner ring, rolling elements and cage in a spherical roller bearing are able to rotate while inclined toward the outer ring.

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As can be seen in Table 1, bearings can be categorized into four groups based on the direction of the force supported and the shape of the rolling elements. For more details, please take a look back at Part 3!

Figure 1 shows the forces applied to the bearing used in a car's wheel with a tire on it. The force generated by the weight of the vehicle (the blue arrow in Figure 1) is applied perpendicular to the axle. Conversely, the centrifugal force generated when the car turns(the red arrow in Figure 1) is applied in the same direction as the axle.

These suffixes indicate that the cage (the part of the bearing that holds the balls apart) is made of polymer material. Usually made of glass-fiber-reinforced polyamide.

As shown in Figure 8, spherical roller bearings can support a large load, and are used in machines where the shaft is easily bent.

In this way, bearings at all times have forces applied from various directions. The bearings are categorized based on which direction the force is coming from and how much force can be applied.

The Deep Groove Ball Bearing, known as 6306-32-2RS-C4-KOYO JTEKT, has an inner diameter of 32 mm, an outer diameter of 72 mm and a thickness of 19 mm.

A stainless steel bearing is generally magnetizable, as it is made from AISI 420 stainless steel, which is harder and more shock-resistant than standard stainless steel (AISI 304).To check whether your bearing is made of stainless steel, simply read the reference engraved on the side of the bearing. This reference should begin with the prefix "S" meaning "Stainless Steel".

Of the four types of bearings listed in Table 1, radial ball bearings and radial roller bearings are used most often. We will explain a bit about those two types of bearings.

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There are various types of bearings categorized by the direction and magnitude of the force they can support, and the optimal bearing type is selected, taking the machine's structure into consideration.There are many other types of bearings we didn't introduce in this article. For those who wish to learn more, please click on the Koyo Bearing product-type pages or the catalog below. You can also contact JTEKT directly.

There are various types of bearings, and we must select the type of bearing most suited to a particular machine's structure and use.

Some bearings are available with more or less important variants (high or low internal clearance, special grease, very high temperature, etc.). These variants are systematically indicated by prefixes and suffixes in the part number.For example, the suffix "2RS" means that the bearing is splash-proof, thanks to a sealing flange on both sides of the bearing.The suffix "C3" means that the bearing has increased internal clearance, and will require a higher operating temperature, or a higher rotation speed.

These suffixes mean "with 1 or 2 rubber seals". At 123Roulement, we use the number "2" to specify when the bearing is sealed on both sides.

Part 1: What Are Bearings? Let's learn about the basic functions of bearings! Part 2: Leonardo da Vinci Was the Father of the Bearing!? The amazing history of bearings Part 3: What's the Structure of the Bearing? The role of the structure and parts in reducing friction Part 4: What Are the Differences Between Bearings? The various types and special features of bearings Part 5: The Applications of Bearings I: This is how bearings are used in cars Part 6: The Applications of Bearings II: This is how bearings are used for machines in industry Part 7: Bearings Made Using Advanced Materials and Lubricants: Bearings all around you

In this part, we will divide the types of bearings into broad categories, and then explain the main features of bearings.

The contact angle is the angle formed by the direction of the load applied to the bearing rings (races) and rolling elements, and a plain perpendicular to the shaft, when a "radial load" and "axial load" are both applied to a bearing.

The ABEC standard is used to classify bearings according to their machining tolerance. This standard is regularly called into question because it does not include certain technologies that are important for guaranteeing proper operation, both in terms of efficiency and bearing life.123Roulement therefore makes little use of this standard.

Bearings support forces applied from various directions, and so they can be categorized based on the "direction of the force". Firstly, we will explain about the forces applied to bearings.

These use needle rollers as their rolling elements. Needle rollers have a smaller diameter than cylindrical rollers, and so (as can be seen in Figure 5) the bearings have a smaller cross-sectional height and contributed to the down-sizing of machinery.

How to Select the Right Bearing (Part 1): The order of priority for selecting bearings, and the types of bearings How to Select the Right Bearing (Part 2): How to decide the bearing arrangement How to Select the Right Bearing (Part 3): Bearing dimensions and service life How to Select the Right Bearing (Part 4): Bearing limiting speed, running accuracy, and fits How to Select the Right Bearing (Part 5): Bearing preload and rigidity How to Select the Right Bearing (Part 6): Bearing lubrication How to Select the Right Bearing (Part 7): Components surrounding the bearing

The Deep Groove Ball Bearing, known as 6306-32-2RS-C4-KOYO JTEKT, has an inner diameter of 32 mm, an outer diameter of 72 mm and a thickness of 19 mm.

The force applied to a bearing is called the "load". The force applied perpendicularly to the shaft is called the "radial load", and that applied in the same direction as the shaft is called the "axial load".

These use cylindrical rollers as their rolling elements. Cylindrical roller bearings can support an even greater radial load than deep groove ball bearings, and are used in machinery where they will experience strong impacts.

These use tapered rollers in the shape of tapered trapezoids as their rolling elements. Tapered roller bearings are the most widely used among all roller bearings, and can support a radial load and a one-directional axial load at the same time. When axial loads coming from both directions are to be supported, two or more tapered roller bearings are combined together.

This suffix indicates that the bearing is designed for very high operating temperatures. In general, the temperature is indicated after this suffix.Beware, these bearings are not suitable for all applications, and will require a high temperature for optimum service life.

Angular contact ball bearings can support a radial load and a one-directional axial load at the same time. When axial loads coming from both directions are to be supported, two or more angular contact ball bearings are combined together.