How to choose the appropriate bearing model

A bearing is a mechanical component that functions to guide rotating components. Therefore, bearings can rotate one component relative to another component.
Bearings are high-precision components that can be effectively transported and loaded,
Enable devices to move horizontally at different speeds.
A bearing must have high precision and durability, and be able to operate at high speeds with minimal noise and vibration frequency.

This type of equipment is used in many projects, such as the automotive industry, aerospace, construction equipment, machine tools, etc.

There are various types of bearings, with the four main types being ball bearings, cylindrical roller bearings, tapered roller bearings, and needle roller bearings.

Although ball bearings are the most common equipment, each type of bearing has its own advantages and disadvantages. That's why we recommend comparing each type of bearing to determine which bearing system is most suitable for you.

When choosing bearings, you must consider several important factors. The first factor to consider is the load that the bearing can withstand. There are two types of loads:

-Axial load: parallel to the axis of rotation
-Radial load: perpendicular to the axis

Each type of bearing is specifically designed to support axial or radial loads. Some bearings can withstand both types of loads simultaneously: we call this a combined load. For example, if your bearings must withstand combined loads, we recommend choosing tapered roller bearings. If you need bearings that can withstand high radial loads, we recommend using cylindrical roller bearings. On the other hand, if your bearings need to support lighter loads, ball bearings may be sufficient as they are usually cheaper.

Rotation speed is another factor to consider. Some bearings can withstand higher speeds. Therefore, cylindrical roller bearings and needle roller bearings with cages have higher rotational speeds compared to bearings without cages. However, sometimes higher speeds come at the cost of sacrificing the load.

You also need to consider possible deviations; Some bearings are not suitable for this situation, such as double row ball bearings. Therefore, attention should be paid to the structure of bearings: embedded bearings and spherical bearings are prone to some alignment deviations. We suggest using self-aligning bearings for adjustment to automatically correct alignment defects caused by shaft bending or installation errors.

Similarly, when choosing ideal bearings, working conditions are also very important. Therefore, it is necessary to analyze the working environment during the operation of bearings. Your bearings may be subject to various types of contamination. Some uses may cause noise interference, shock, and/or vibration. Therefore, your bearings must be able to withstand these impacts while not causing inconvenience.

Another fundamental factor to consider is the lifespan of the bearings. Various factors such as speed or repeated use can affect the lifespan of bearings.

Choosing a sealing system is the key to ensuring the correct and long-lasting operation of bearings; Therefore, it is necessary to ensure that the bearings are always well protected from any impurities and external factors, such as dust, water, corrosive liquids, or even used lubricants. The choice depends on the type of lubricant, environmental conditions (and therefore pollution type), fluid pressure, and rotational speed.
To give you a good starting point, fluid pressure is the determining factor in choosing a sealing system. If the pressure is high enough (such as within the range of 2-3 bar), mechanical seals are ideal. Otherwise, the choice will be directly related to the type of lubricant, grease, or oil. For example, for grease lubrication, the most commonly used solutions are deflectors or washers, machined or narrow channels with grooves; In the case of oil lubrication, the sealing system is usually accompanied by grooves for oil recovery.

The usage conditions can also affect your choice, especially when assembling bearings. It is also necessary to consider the rigidity and accuracy required for bearings during use. In some cases, preloads can be applied to the bearing components to increase their stiffness. In addition, preloading will have a positive impact on bearing life and system noise levels. Please note that if choosing preload (radial or axial), it is necessary to understand the rigidity of all parts through software or experiments.

In your selection criteria, you must also consider the ideal material for the bearings. Bearings can be made of metal, plastic, or ceramic. The material of the bearing depends on its intended use. We recommend that you choose the most compression resistant bearings. However, the materials used will affect the price of the bearings.

Ball bearings are typically optimized for radial contact: this means that if you want the force of the bearing contact to be perpendicular to its axis of rotation, ball bearings are very effective. However, double row ball bearings have been optimized for inclined contact. In addition, if you want to use a ball bearing to withstand axial loads, it should be noted that the device only supports moderate axial loads. However, using a double row ball bearing structure can avoid this defect. In addition to low cost, ball bearings are also the most compact, making them the most widely used type of bearing.

We strongly recommend using ball bearings on small bearings that operate at high speeds.

Each type of bearing can be deep groove, spherical or embedded. Deep groove bearings are the most common. Embedded bearings are also deep groove bearings, which, like spherical bearings, can effectively withstand the effects of misalignment.

The difference from spherical bearings is that their rotation angle is smaller. The larger the rotation angle, the greater the deviation that the bearing can withstand.

Another factor to consider is that depending on usage, you may need a rotating shaft (such as a car wheel drive bearing) or a rotating wheel hub (such as a washing machine bearing).

Then, you need to pay attention to the assembly method of the bearings. If two bearings are too close to each other, the O-shaped assembly method should be used to avoid interference between the bearings. If this is not the case, then the X assembly method is the most suitable.

In short, each bearing has a specific size. These dimensions are expressed in millimeters and comply with international standards. Therefore, we suggest that you pay attention to the holes of the bearing, namely the inner diameter (always represented by the lowercase letter d), outer diameter (represented by the letter D), and width (represented by the letter B).

Choosing lubricants is an important factor in ensuring the normal operation of bearings and extending their service life. Lubricants have the following functions:

Make movement easier
Avoid wear and material fatigue
Reduce internal friction
Ensure the bearing is sealed with external objects
Reduce work noise
Protect bearings from corrosion
You have two choices: lubricating grease or engine oil.
Generally speaking, grease lubrication is definitely the simplest and most effective choice because it has all the functions mentioned above and has lower maintenance costs. However, if your bearings are integrated into an oil lubricated machine, we recommend using the same lubrication system.
In any case, the choice of lubricant depends on three factors: load, type of operation (continuous or intermittent), and rotational speed.
If bearings are prone to high loads, continuous operation, and high rotational speeds, oil lubrication is the ideal solution to ensure the normal operation of the rolling system.
On the contrary, if the load is low and the speed is limited, then using lubricating grease is sufficient.

My name is Jack, and I am a bearing R&D engineer. If you require assistance with bearing design or need to purchase bearing-related components, please do not hesitate to contact me; I will provide you with the perfect solution.