Precision Bearings

What’s the precision bearings?

Precision bearings are a type of bearing with high-precision manufacturing and performance characteristics, playing a crucial role in various fields that require high-precision motion control and stable operation.

Features of the precision bearings

High Precision

Dimensional Accuracy：The manufacturing process of precision bearings strictly controls the dimensions of each component. The dimensional tolerances of the inner and outer rings, rolling elements, and cages are extremely small. For example, in some ultra-precision bearings, the dimensional error of the inner and outer ring diameters can be controlled within a few micrometers.

Runout Precision：They have extremely low runout, which means that during the rotation of the bearing, the radial and axial runout is minimal. This is crucial for applications that require high-precision rotation, such as in optical processing equipment, where the runout of the spindle bearing needs to be controlled within a very small range to ensure the accuracy of optical component processing.

Low Friction

Smooth Surface Finish: The raceway surfaces of precision bearings are polished to a high degree of smoothness. The low surface roughness reduces the frictional resistance between the rolling elements and the raceways. As a result, the bearing can operate with lower energy consumption and less heat generation.

Optimal Lubrication Design: They are often designed with optimized lubrication channels and grease filling methods. This ensures that the lubricant can be evenly distributed within the bearing, further reducing friction and wear.

High Rigidity

Strong Structural Design: Precision bearings usually have a more robust structural design. The thickness and material of the inner and outer rings are carefully selected and designed to improve the bearing's ability to resist deformation under load.

High Load-Carrying Capacity: They are capable of withstanding high radial and axial loads while maintaining their precision. For example, in heavy-duty machine tools, precision bearings need to support the large cutting forces and axial thrust generated during machining, ensuring the stability and accuracy of the machine tool's operation.

Good Stability

Resistance to Thermal Expansion: The materials used in precision bearings have low thermal expansion coefficients. This means that under different temperature conditions, the bearing's dimensions change very little, maintaining its original precision and stability.

Vibration and Noise Reduction: Precision bearings are designed to reduce vibration and noise. Their precise manufacturing and balanced structure minimize vibration during operation, resulting in quiet operation.

High-Speed Performance

Low Centrifugal Force: The rolling elements and cages of precision bearings are designed to have low centrifugal force at high speeds. This allows the bearing to maintain stable operation and reliable performance even at extremely high rotational speeds.

Good Heat Dissipation: They have good heat dissipation performance. At high speeds, the heat generated by the bearing can be quickly dissipated to prevent overheating, which could affect the bearing's performance and lifespan.

Types of the precision bearings

1. Ball Bearings

Deep Groove Ball Bearings:

The most common type, used for radial and axial loads.

Suitable for high-speed and low-noise applications.

Used in everything from electric motors to automotive components.

Angular Contact Ball Bearings:

Designed to handle both radial and axial loads.

Often used in high-speed applications (e.g., machine spindles, robotics).

The contact angle between the balls and the raceways allows for higher axial load handling.

Self-Aligning Ball Bearings:

Have two rows of balls and a common spherical raceway.

Automatically align in case of shaft misalignment, making them ideal for certain industrial applications.

Ceramic Ball Bearings:

Use ceramic balls (usually silicon nitride) to reduce friction and increase performance.

Offer better heat resistance and wear resistance compared to traditional steel bearings.

Often used in high-speed or high-precision applications like turbines and medical equipment.

2. Roller Bearings

Cylindrical Roller Bearings:

Use cylindrical rollers instead of balls, offering higher radial load capacity.

Good for high radial loads at moderate speeds.

Suitable for heavy-duty industrial machinery and automotive.

Tapered Roller Bearings:

Designed to handle both radial and axial loads.

The inner and outer raceways are tapered, which helps to distribute the load better.

Commonly used in wheel hubs, gearboxes, and truck axles.

Needle Roller Bearings:

A type of cylindrical roller bearing with small diameter rollers, allowing for a compact design.

Ideal for applications where space is limited but high load-bearing capacity is required.

Used in automotive, industrial, and aerospace applications.

Spherical Roller Bearings:

Have two rows of rollers and are designed to accommodate misalignment.

Ideal for heavy-duty applications where shaft deflections or misalignment occur.

Common in heavy machinery, mining, and wind turbines.

3. Thrust Bearings

Thrust Ball Bearings:

Specifically designed to handle axial loads.

Ideal for low to medium speed applications with axial loading requirements.

Common in gearboxes, automotive, and aerospace systems. 

Tapered Thrust Bearings:

A combination of tapered roller bearings and thrust bearings, capable of handling both axial and radial loads.

Used in applications such as automotive transmissions, rotary tables, and conveyor systems.

Needle Thrust Bearings:

A variant of needle bearings designed to support axial loads.

Often used in high-precision applications like medical devices and instruments.

4. Magnetic Bearings

Active Magnetic Bearings (AMBs):

Use magnetic fields to levitate a rotating shaft, reducing friction.

Often used in high-speed applications such as turbines, flywheels, and pumps.

Passive Magnetic Bearings:

Use permanent magnets to provide a magnetic bearing force without requiring active control systems.

Often used in applications where precision control is not as critical.

5. Hybrid Bearings

Hybrid Ceramic Bearings:

Incorporate ceramic balls with steel races to combine the benefits of both materials.

Offers reduced friction, heat resistance, and longer life compared to full steel bearings.

Commonly used in high-speed and high-precision environments.

6. Thin-Section Bearings

Thin-Section Ball Bearings:

Feature a thin outer ring and reduced bearing cross-section.

Provide a compact design with high precision.

Often used in aerospace, robotics, and machine tools.

7. Custom Bearings

Custom Precision Bearings:

Designed to meet very specific application requirements in terms of size, load capacity, and material.

Used in specialized industrial applications, medical devices, or in scientific instruments.

Summary Table of Bearing Types

How to select the precision bearings?

1. Identify the Type of Load

Radial Loads: If the bearing will primarily support forces perpendicular to the shaft, such as in motors or conveyors, you may need radial ball bearings (e.g., deep groove ball bearings).

Axial Loads: If the bearing is subjected to forces along the shaft, consider thrust bearings (e.g., thrust ball bearings or tapered roller bearings).

Combined Loads: If the bearing needs to handle both radial and axial loads, angular contact ball bearings or tapered roller bearings are good options.

2. Consider the Operating Speed

High-Speed Applications: Choose bearings designed for low friction and minimal heat generation, such as ceramic ball bearings or hybrid bearings (ceramic balls with steel races).

Moderate to Low-Speed Applications: Regular steel ball bearings or cylindrical roller bearings may suffice.

High-Speed Precision: For maximum performance at very high speeds, consider angular contact ball bearings, which offer excellent precision.

3. Determine the Load Capacity

Radial Load Capacity: Ensure the bearing type can handle the expected radial load. Cylindrical roller bearings offer higher radial load capacity than ball bearings.

Axial Load Capacity: If the application involves significant axial loads, go for tapered roller bearings or angular contact ball bearings, which are designed for handling both radial and axial loads.

4. Precision Level (Tolerance)

Tolerance Grade: Choose a bearing with the correct precision grade (e.g., P0, 6, 5, 4, or 2) based on your application's accuracy requirements.

P0: Standard tolerance for general industrial applications.

P6/5: Suitable for moderate precision, widely used in machinery and automotive.

P4/2: Used in high-precision applications like aerospace, robotics, and high-speed machinery.

Higher ISO grades or P4/P2 tolerance levels also indicate higher precision, which is necessary for applications where minimal runout or vibration is critical.

5. Consider Environmental Conditions

Temperature: Bearings designed for high or low temperatures (such as ceramic bearings) are important in environments with temperature extremes.

Corrosion Resistance: If the bearing is exposed to moisture, chemicals, or corrosive environments, choose bearings made from stainless steel, or use sealed or shielded bearings for added protection.

Cleanliness: In clean room applications (like in the semiconductor or medical industry), cleanroom-grade bearings with low contamination and smooth surfaces are essential.

6. Bearing Size and Space Constraints

Space Restrictions: For applications with limited space, you may need thin-section bearings or needle roller bearings.

Load Requirements: Ensure the bearing size matches the expected load and torque. Larger bearings often carry more load but may not fit into smaller spaces.

7. Bearing Material

Steel Bearings: Most common, offering good strength, toughness, and resistance to wear. However, they may be prone to corrosion.

Stainless Steel Bearings: Ideal for harsh environments (moisture, chemicals), though they may have slightly lower strength than carbon steel.

Ceramic Bearings: Offer low friction, high wear resistance, and can withstand higher temperatures. They are often used in high-speed and high-precision applications.

Hybrid Bearings: Combination of ceramic balls and steel races provide lower friction, heat resistance, and longer life.

8. Lubrication Requirements

Greased Bearings: Common in general industrial applications, providing long-lasting lubrication but requiring maintenance.

Oiled Bearings: Suitable for high-speed applications, offering lower friction but may need more frequent lubrication.

Sealed Bearings: Pre-lubricated and sealed to prevent contaminants from entering the bearing, reducing maintenance needs.

Shielded Bearings: Similar to sealed bearings but with less protection against contamination.

9. Vibration and Noise Considerations

Low Noise Requirements: In high-precision machinery or applications like medical equipment or robotics, noise and vibration can affect performance. Choose bearings with minimal runout, such as angular contact ball bearings or ceramic bearings, which reduce vibrations.

Minimized Runout: Bearings with tighter tolerances will help minimize vibrations and ensure smooth operation.

10. Cost vs. Performance

Precision bearings can vary significantly in cost based on the materials, tolerances, and design. Choose the best bearing that meets your requirements while balancing performance and cost.

Consider the total cost of ownership, which includes maintenance and potential replacement costs. For high-precision applications, investing in higher-quality bearings may result in fewer failures and less downtime.

Summary of Key Selection Criteria

Step-by-Step Selection Process

1.Define application requirements (load type, speed, precision, environment).

2.Choose bearing type (ball, roller, thrust, or hybrid).

3.Determine the required load capacity (radial, axial, or combined).

4.Select precision grade (P0,6,5, ISO, or P4/P2).

5.Choose appropriate materials (steel, ceramic, hybrid, stainless).

6.Consider lubrication needs (sealed, greased, or oiled).

7.Review environmental factors (temperature, contaminants, moisture).

8.Check bearing size and space constraints.

By carefully considering these factors, you can select the ideal precision bearing for your specific application.

If you’d like further guidance or have a particular application in mind, feel free to share details!

Price of the precision bearings

For specific price details, you can communicate with our staff.

Supplier of the precision bearings

NEWBEE Transmission is a precision bearing company boasting over ten years of rich experience. We have professional and modern production workshops, dust - free assembly workshops as well as testing equipment. Our team is composed of senior engineers, senior technicians, professional inspectors and quality assurance staff, enabling us to offer customers professional precision bearing solutions.