In previous Bearing Trivia entries, we introduced the fact that bearings are used in many machines and are a very important machine component. We focused in those columns on topics like bearing structure and so on.
Click here to get more.
"What's the Structure of the Bearing? The role of the structure and parts in reducing friction"
"What Are the Differences Between Bearings? The various types and special features of bearings"
When designing a machine, it is important to select the bearing that is right for that machine.
JTEKT has published a guide for selecting the right bearing in its Ball & Roller Bearings Catalog, but the catalog uses a large number of technical terms and is very long, so many people seem to have trouble handling it.
That's where this column comes in. We will explain the key points for selecting the type of bearing that is right for your machine.
The catalog uses the terms "bearing" and "rolling bearing" interchangeably. This column does not use the term "rolling bearing" as a general rule.
Bearings come in a variety of types, and their sizes can range from just a few millimeters to over ten meters in diameter.&#;
Fig. 1: Extra-small (miniature) bearings
Fig. 2: Ultra large slewing rim bearing for tunnel excavators
When selecting from among these many varied types of bearings, the bearing that is right for your machine, the following two criteria are very important.
If these criteria are met, damage of the machine can be reduced, the time needed to replace the bearings when performing repairs can be shortened, and the machine can be used for a longer period of time.
In this way, selecting the appropriate bearing will lead to machine design that is economically superior!
In the "How to Select the Right Bearing" columns, we will select the optimal bearing based on the ordering shown in Table 1, below.
Please note that the following order is only a guideline.
When you actually select the bearing to use, the most important factors are past success history and points of improvement, so it is not necessary to follow this order to the letter.
Table 1: Bearing selection checklist
Order Examination item Major points to confirm &#; Bearing type What magnitude and direction of load do you need? Will it fit in the installation space?When designing a machine, most people first decide on the dimensions of the shaft to satisfy the strength requirement, and then select the bearing based on that.
1) If the load will be mostly radial (perpendicular to the shaft), use a radial bearing, and if the load will be mostly axial* (same direction as the shaft), use a thrust bearing. * Axial loads are sometimes called thrust loads.
2) If the load on the bearing will be light, use a ball bearing, and if it will be heavy, use a roller bearing.
Fig. 3: The radial and axial loads
Table 2: The various types of bearings and loads placed on bearings
Rolling element Ball Roller Direction in which load is mostly applied Perpendicular to the shaftradial load
) Radial ball bearing Radial roller bearing The same direction as the shaftaxial load
) Thrust ball bearing Thrust roller bearingFig. 4: Radial bearings
Fig. 5: Thrust bearings
3) If a radial load and an axial load are both placed on a single bearing at the same time (combined load), a light combined load calls for a deep groove ball bearing or an angular contact ball bearing, while a heavy combined load calls for a tapered roller bearing.
Fig. 6: The radial and axial loads (combined load) applied to an angular contact ball bearing
If there is a heavy axial load being applied from both directions, you can combine two or more bearings, or use a double-row bearing.
Fig. 7: A matched pair of bearings (angular contact ball bearings)
Fig. 8: A double-row bearing (tapered roller bearing)
Our bearing catalog contains a table showing the boundary dimensions (dimensions required for bearing installation with shaft and housing) as in Table 3, below. Using the table of boundary dimensions, select a bearing type that will fit in the installation space based on the dimensions of the shaft or housing.
What is housing?
1) In the table of boundary dimensions, the dimensions such as bearing outside diameter and width (or height in the case of a thrust bearing), corresponding to a specific bearing bore diameter, are shown in series.
2) The "dimension series code" refers to a combination of the width series and the diameter series that has a stepped bearing outside diameter with respect to the bearing bore diameter.
Table 3: An example of the bearing boundary dimensions table (a spherical roller bearing)
Bearing type Bearing series code Type code Dimension series code Width series Diameter series Spherical roller bearing 239 2 3 9 230 2 3 0 240 2 4 0 231 2 3 1 241 2 4 1 222 2 2 2 232 2 3 2 213 2 0 3 223 2 2 3Reference: Bearing series code
3) Even if a bearing has the same bore diameter, there are several types of width and outside diameter, so select the appropriate bearing from among them.
[see Fig. 9 a) ]
Some people choose bearings based on the outside diameter of the bearing that matches the dimensions of the housing.
[see Fig. 9 b) ]
Fig. 9: Bearings with the same bore diameter or the same outside diameter
Reference: Dimension series diagrams of radial bearings and thrust bearings
4) Select the bearing of diameter series 0, 2, or 3 from the example of Table 3. If the bearing installation space is limited due to the down-sizing of the machine, select a bearing of diameter series 9.
If the installation space is limited only in the radial direction, select a bearing with a width (or height in the case of a thrust bearing) series 2 or higher, or a double-row bearing. The width series is omitted for some bearing types (such as deep groove ball bearings), so please check the Ball & Roller Bearings Catalog for details. At this stage of selecting the bearing type, it is best not to limit yourself to one type, but to select multiple types.
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Check that the type of bearing you have selected is generally appropriate by using the "Performance comparison of bearing type" (Table 4).
Table 4: Performance comparison of bearing type
Deep groove ball bearing Angular contact ball bearing Single-row Single-row Double-row LoadPerformance comparison of bearing type
Check that the type of bearing you have selected is generally appropriate by using the "Selected bearing type checklist" (Table 5).
Table 5: Bearing selection checklist
Order Examination item Major points to confirm &#; Bearing type What magnitude and direction of load do you need? Will it fit in the installation space?When selecting the bearing that is right for your machine, it is important that the bearing be appropriate for the requirements of the usage environment and that it be easily acquired for replacement. In the "How to Select the Right Bearing" columns, we will show you how to do this.
In this month's column, "How to select the type of bearing," we conveyed the following points:
Deep Groove Ball Bearings are another term for radial ball bearings. These bearings support both radial and axial loads with balls as the rolling element. Grooves in both the inner and outer rings provide a path of travel for the balls. The deep groove geometry facilitates efficient handling of a combination of loads while maintaining a relatively simple design. In this article, we will explore the various types of Deep Groove Ball Bearings.
Standard Deep Groove Ball Bearings (SKF series)
The 200 series is the most common ball bearing design found in most standard applications. 200 series Deep groove ball bearings are used in electric motors, hand tools like drills and saws, and hundreds of other applications from automotive to medical devices. These bearings handle light to moderate and some heavy loads but are primarily used for medium-load applications. They truly are the most utilized ball bearing series. 200 series ball bearings are made of chrome steel. Standard DGBBs (Deep Groove Ball Bearings )are engineered to handle both radial and axial loads effectively, making them the best choice for applications like electric motors, household appliances, and general industrial machinery. Buy TPI, FAG, and other high-quality 200 series ball bearings from: https://pibsales.com/product-category/radial-ball/
Shielded Bearings (FAG ZZ)
Shielded bearings incorporate metal shields to protect against dirt and debris. While they don't completely seal the bearing, these shields significantly reduce the ingress of contaminants and the leakage of lubricant. They are ideal for environments where there's potential for contamination but still a need for temperature and speed performance, such as in certain industrial settings. 300 series DGBB ball bearings are ideal for heavy-duty applications. To purchase 300s series ball bearings with ZZ shields visit: https://pibsales.com/product-category/radial-ball/
PIB offers top-quality brand names such as TPI, FAG, SKF, and more from stock
Sealed Bearings (FAG -2RSR)
series bearings are best used in light duty applications. In the case of a -2RSR size it will feature rubber seals on both sides while offering superior protection against contaminants and better lubricant retention. Suited for applications where contamination and moisture are major concerns, sealed bearings may have lower speed limits due to increased seal friction. They are commonly found in agricultural machinery, outdoor equipment, and high-contamination industrial settings. PIB offers LLU seal designs from TPI bearing for use under heavy water pressure and full sealing ability. To purchase sealed ball bearings for light, medium and heavy duty applications visit: https://pibsales.com/product-category/radial-ball/
High-Temperature Bearings (NTN HT200)
NTN and other manufacturers offer 200 series bearings designed for high-temperature environments. Pacific International Bearing offers these bearings which use heat-stabilized materials and special lubricants. They can operate in temperatures up to 200°C, making them suitable for applications like kilns and steel mills, where standard bearings would fail due to the extreme heat.
To purchase high temperature bearings please contact us at
Ceramic Ball Bearings (Timken PP)
series utilizing ceramic balls, these bearings are lighter, harder, and more wear-resistant than their steel counterparts. They offer reduced friction, lower operating temperatures, and minimal lubrication requirements, making them ideal for high-speed applications such as dental drills, spindles, and high-performance motors. Pacific International Bearing Sales offers a variety of miniature, standard or even heavy-duty bearings as hybrid or as fully ceramic ball construction. To purchase ceramic ball bearings please contact us at .
Stainless Steel Bearings (SKF W-2RS1)
Constructed entirely of stainless steel, including the balls, races, and cages, these bearings offer superior corrosion resistance. They are particularly suited for environments where there is exposure to corrosive elements, making them ideal for use in food processing, medical equipment, and marine applications.
To purchase fully stainless steel bearings contact us at
Design Principles of Deep Groove Ball Bearings
Standard Deep Groove ball bearings are ABEC 1 , chrome bearing steel, and are produced in massive quantities in highly automated factories.
The components for a ball bearings include inner and outer ring, balls, retainer, seals or shields and grease.
In some cases rings can be made from corrosion resistant materials, balls from ceramic, and cages from plastic or steel or phenolic. Different manufacturers offer seals and shields from various materials. In today's world a bearing can have almost every feature tweaked to obtain the highest level of performance possible for every application.
In addition, quality and tolerance specifications are standardized to conform with ABEC and ISO organizations. These standards define the level of precision and consistency in the bearing's dimensions and rotational accuracy. High-precision bearings meeting the highest standards are essential in applications where minimal noise and vibration are required, such as in high-speed machinery and precision instruments.
Lubrication in DGBBs is chosen based on factors like operational speed, temperature conditions, and environmental exposure. The type of lubricant&#;whether it's grease, oil, or solid-based&#;plays a significant role in reducing wear and extending the bearing's service life.
Some bearings come with pre-applied lubricants, tailored to provide optimal performance throughout the bearing's lifespan.
Applications of Deep Groove Ball Bearings
In the automotive industry, DGBBs are extensively used due to their ability to withstand both radial and axial loads, a necessity for vehicle components. They are found in clutch release bearings, alternators, and wheel hubs, where their durability and low maintenance requirements are crucial for the longevity and performance of the vehicle.
Industrial machinery is another application where DGBBs are indispensable. In this sector, they are utilized in electric motors, conveyors, and pumps. Their role in electric motors, in particular, is critical; they support the motor's rotational movement, ensuring efficiency and reducing energy consumption. The ability of DGBBs to operate at high speeds with minimal noise and vibration is especially beneficial in high-speed machinery, contributing to smoother operation and increased machinery lifespan.
In the aerospace industry, the precision and reliability of DGBBs are vital. They are used in various aircraft components, including gearboxes and control systems. The high precision and low-torque resistance of DGBBs are essential in these applications, where every component's performance can impact the overall safety and functionality of the aircraft.
Consumer electronics also benefit from the use of DGBBs. In devices like hard drives and DVD players, small and precise bearings are necessary for the fast-moving and intricate parts. The low noise and vibration characteristics of DGBBs are particularly advantageous in these applications, where they contribute to the device's overall performance and user experience.
PIB Sales offers an extensive range of products tailored to meet your project needs. Our online includes the latest innovations and specialized bearing types, ensuring you find the perfect match for your application. Whether you're looking for standard bearings for general use or specialized bearings for high-precision applications, PIB Sales is your go-to source for reliability and performance. Visit our online shop today or contact us at