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Complete Guide to Ball Bearing Types

🔗 Mechanical transmission

Date of publication : 23/10/2023

Reading time : 4 Minutes


Ball bearings reduce friction between two rotating parts by distributing the load over a large number of balls.

Ball bearings are the most widely used bearings in various products and applications. They can withstand radial and axial loads, but are used in light load applications. Used in a variety of applications of all shapes, sizes and complexities, bearings remain a cost-effective solution for different categories, products and industries.

Sizing of ball bearings

Bearing sizing is an essential step when designing or maintaining mechanical machines and equipment. Improper bearing selection can lead to premature failure, high repair costs and inefficient operation. Here are the boxes to fill in to select the right bearing based on your specific needs :

What is the best brand of ball bearing ?

Installation of ball bearings 

Under radial load, the rings of rotating bearings tend to rotate on their seats or housings, causing premature wear of the seat. It is therefore generally necessary to connect the rings to the assembly parts (shaft, housing) so that they become an integral part. Generally, when installing ball bearings, the rotating ring relative to the load direction should be installed firmly, and the fixed ring relative to the load direction should be free. There are many bearing mounting techniques.

Cold bearing assembly

Cold fitting is a simple approach, suitable for small and medium sized bearings, in combination with standard fits. The bearing can then be installed by gently tapping the ring on the ring with a hammer for a snug fit. This must be clean and have parallel planes without burrs. Remember to lubricate the bearing with light oil to avoid damage to the shaft during assembly. Installation is then carried out using a plain bearing protruding from the bearing race with the tightest fit. This avoids stress on the rolling body and damage to components when installing the bearings.

If there is an internal thread on the shaft, it can be used for bearing assembly. With a hydraulic press and removable shaft, the shaft and bearing can be aligned by using a mounting ring or bushing between the press and the bearing ring. Be sure to maintain alignment throughout press assembly, never exceeding the capacity of the press to avoid bearing damage.

If there is an internal thread on the shaft, it can be used for bearing installation. If you have a hydraulic press and the shaft is removable, you can place the shaft in the center of the axis of the press with the bearing, by interposing a ring or a mounting bush between the press and the ball bearing ring. Throughout the press assembly procedure, it is imperative to maintain alignment. It is essential to never exceed the capacity of the press, otherwise the integrity of the ball bearing will be compromised during installation.

Hot bearing assembly

Hot mounting is common for press fitting bearings onto shafts requiring considerable force due to their size and high tolerances. The induction heating method is often favored for its safety, cleanliness and speed, outperforming alternatives such as oil bath, hot plate or oven.

The heating temperature depends both on the size of the ball bearing on the one hand, and on the other hand, on the fit and material of the bearing surface. The temperature must not be too high (maximum 130°C), otherwise it could modify the particular properties of the steel or the internal parts of the bearing.

In this method of assembly of ball bearings, heating causes the bearings to expand, followed by their installation and cooling to room temperature. This process causes the inner ring to contract, ensuring a secure fit on the shaft. After assembly, the bearings shrink in both axial and radial direction during cooling.

Lubrication of ball bearings

There are several types of bearings and self-aligning bearings, although bearings are the most popular mechanism.

Common bearings are essentially composed of four elements: the outer ring, the inner ring, the rollers generally made of treated steel, and the cage, which can be made of metal, plastic or other composite materials. The function of the cage is to keep the rollers positioned relative to each other, located between the two rings. In the case of ball bearings, the rolling elements are balls that move along the raceway, providing the contact surface between the balls and the ring.The whole thing is then lubricated with grease or oil to reduce friction and wear.

Bearings may have seals to retain lubricant and prevent dust contamination. However, over time, especially unprotected bearings, can accumulate impurities, causing seizure. To ensure extended life, proper maintenance, including lubrication with oil or of the fat specifically designed for bearings, is essential.

Bearings can be equipped with seals to retain lubricants or grease, while preventing parts from becoming contaminated by dust or dirt. And over time, bearings, especially those without protective seals, tend to accumulate dirt which affects their normal operation. This phenomenon is called seized bearing. To ensure a long lifespan for bearings, it is necessary to maintain them well, in particular by lubricating them with bearing oil or bearing grease.

What are the different types of ball bearings?

Bearings are named based on their physical design characteristics. By understanding their design, one can appreciate the logical relationship between the design, name and load capacity of each of the following types of bearings:

Rigid ball bearings

Rigid ball bearings mainly support radial loads and small charges axially simultaneously in both directions. Rigid ball bearings are reputed For their versatility, low cost and capacity to operate at speeds high. 

Spherical ball bearings

Spherical ball bearings create less friction than any other type of bearing, resulting in less heat generation, even at high speeds. This type of bearing is recommended when the shaft is bent and when alignment between the shaft and housing is difficult.

Angular contact ball bearings

Angular contact ball bearings are designed such that a contact angle is formed between the rings and the ball when the bearing is used. The main characteristic of this type of bearing is that one or both rings have a higher shoulder than the other.

Self-aligning bearings

Self-aligning bearings, also called mounted bearings or bearings, are used to support and guide the shaft of a machine or equipment, thus allowing rotation gentle and reducing friction between the surface of contact. The bearings are designedFor sustain AndTO DO turn THE trees effectively while minimizing the friction And The loss of energy. They generally consist of three main components: The rolling element, the cage and the housing.

Precision ball bearings

Precision ball bearings have been especially developed to suit applications involving high speed high and this with a big precision. They are designed to produce little heat while maintaining controlled rigidity in the most demanding applications. 

Ball thrust bearings

Ball thrust bearings are of two types: THE single-acting thrust bearings (1 row of balls) andTHE stops double acting (2 rows of balls).THE stops single-acting support axial loads in one direction, whileTHE stops has double effect support of the charges axial in both ways.

THE benefits of deathstops ballare boundaries. In effect, minimum axial loadEast necessary For Ensure ball rolling and operation normal of the stop.They aredesigned Forsupporter uniquely axial loads and must under no circumstances support radial loads.

Where to buy ball bearings?

Ball bearing, where to find them? when they need to be replaced or when an application requires the installation of a specific bearing, There are stores specializing in the sale of bearings like ITAFRAN. To find a bearing, whatever its application and whether you are a professional, individual, craftsman, repairer or DIYer, ITAFRAN offers you countless references and thousands of bearing samples in stock with same day delivery if you order before 6 p.m. You will also find the biggest bearing brands, whatever their type: NSK, CMW, IKO, KOYO… By using the search tool integrated on the site and its various filters, you can easily find the ball bearing which will meet all your mounting and application needs.

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