Small Ball Bearings: Sizes, Uses & Buying Guide
- sociocon20
- Aug 16
- 12 min read
If you're looking for small ball bearings, choosing the right bearing isn't simply about finding one that fits the shaft. Bore size, outside diameter, width, load capacity, operating speed, sealing, lubrication, precision, and the available mounting space all need to be considered before making a purchase.
At Kashyap Bearing, we help customers identify suitable small ball bearings based on the actual machine requirement rather than selecting a bearing only by size. Whether you need small ball bearings for electric motors, fans, robotics, automation equipment, instruments, pumps, 3D printers, or general machinery, you can share the bearing number, dimensions, photograph, shaft size, or application details with our team.
Kashyap Bearing has been serving customers from SP Road, Bangalore since 1987, supplying a wide range of bearings and industrial products for different applications.
📍 #11/1 SP Road, Bangalore 560002 📞 9448516463 / 8951322259 💬 WhatsApp us with your bore size and application — we'll tell you exactly which double row angular to buy.
What Are Small Ball Bearings?
Small ball bearings are compact rolling-element bearings that use balls between the inner and outer rings to reduce friction and support rotating components.
They are designed for applications where a relatively small shaft and compact bearing arrangement are required.
Small ball bearings are commonly used in:
Electric motors
Cooling fans
Pumps
Robotics
Automation equipment
3D printers
Office equipment
Small machinery
Precision instruments
Material-handling equipment
Depending on the application, small ball bearings can be available in open, shielded, sealed, flanged, stainless steel, and other configurations.
How Do Small Ball Bearings Work?
A small ball bearing generally consists of:
Inner ring
Outer ring
Balls
Cage
The inner ring is fitted to the rotating shaft while the outer ring is mounted within the housing or surrounding structure.
As the shaft rotates, the balls roll between the raceways. This reduces sliding friction and allows the shaft to rotate smoothly.
The cage keeps the balls appropriately spaced during operation.
The exact construction can vary depending on the bearing type.
Why Are Small Ball Bearings Used?
Small ball bearings are useful when a machine requires reliable rotation but has limited installation space.
They can offer:
Compact dimensions
Low friction
Smooth rotation
Reduced weight
Easy installation
Good rotational performance
Wide range of configurations
They are particularly useful in compact mechanical assemblies where a larger bearing would take up unnecessary space.
Types of Small Ball Bearings
Small ball bearings are available in several configurations.
The most common types include:
Small Deep Groove Ball Bearings
Shielded Small Ball Bearings
Sealed Small Ball Bearings
Open Small Ball Bearings
Flanged Small Ball Bearings
Stainless Steel Small Ball Bearings
Small Angular Contact Ball Bearings
Small Thrust Ball Bearings
Ceramic and Hybrid Small Ball Bearings
Extended Inner Ring Bearings
Let's look at these types in more detail.
Small Deep Groove Ball Bearings
Small deep groove ball bearings are among the most widely used small bearing types.
They are designed primarily for radial loads and can also accommodate suitable axial loads.
Their relatively simple construction makes them suitable for many general-purpose applications.
Common uses include:
Small electric motors
Fans
Pumps
Office equipment
Automation machinery
Robotics
Small gear-driven systems
For general rotating applications, a small deep groove ball bearing is often one of the first options to consider.
Shielded Small Ball Bearings
Shielded ball bearings use shields to help protect the internal components from larger contaminants and retain lubricant.
They are commonly used in relatively clean applications where some protection is required.
Typical applications include:
Electric motors
Fans
Small machinery
Office equipment
Electronic equipment
Shielded bearings can also be suitable for applications where lower friction and rotational performance are important.
Sealed Small Ball Bearings
Sealed small ball bearings use seals to provide additional protection against dust and moisture.
They can be useful when the bearing operates in environments where contamination is more likely.
Applications may include:
Outdoor equipment
Small pumps
Agricultural equipment
Automation systems
Compact machinery
The appropriate seal type depends on factors such as speed, temperature, lubricant and contamination.
Open Small Ball Bearings
Open bearings do not have external shields or seals.
They can be suitable when the bearing is installed inside a protected housing or where relubrication is required.
Advantages can include:
Easy access for lubrication
Lower sealing resistance
Suitable heat dissipation in certain applications
However, they offer less protection from external contaminants.
Flanged Small Ball Bearings
Flanged small ball bearings have an integrated flange on the outer ring.
The flange can help position the bearing within the housing and can simplify installation in certain applications.
They are commonly used in:
Small instruments
Printers
Robotics
Compact machinery
Automation equipment
Flanged bearings can be particularly useful where axial positioning of the bearing is required.
Stainless Steel Small Ball Bearings
Stainless steel ball bearings can be useful where corrosion resistance is important.
Potential applications include:
Medical equipment
Food-processing machinery
Laboratory equipment
Outdoor machinery
Wet environments
Equipment exposed to cleaning processes
However, stainless steel construction alone doesn't determine whether a bearing is suitable for a particular environment. Seals, lubricant and the complete bearing construction should also be considered.
Small Angular Contact Ball Bearings
Small angular contact ball bearings are designed to accommodate radial and axial loads through an angled contact arrangement.
They can be useful in compact applications where controlled axial positioning or combined loading is required.
Applications can include:
Precision machinery
Small spindles
Robotics
Instrumentation
Compact drive systems
The correct arrangement depends on the direction and magnitude of the loads.
Small Thrust Ball Bearings
Small thrust ball bearings are primarily designed for axial loads.
They are useful when the main force acts parallel to the shaft.
Applications can include:
Small actuators
Rotary mechanisms
Instrumentation
Compact machinery
Positioning systems
They should not be used as a substitute for a radial ball bearing when significant radial loads are present.
Ceramic and Hybrid Small Ball Bearings
Some small ball bearings are available with ceramic rolling elements.
Hybrid bearings combine ceramic balls with steel rings.
These bearings can be considered for specialized applications where factors such as:
High speed
Low friction
Electrical insulation
Precision
are important.
They are generally more application-specific than conventional steel ball bearings.
Extended Inner Ring Bearings
Some small ball bearings are available with an extended inner ring.
The extended inner ring can simplify mounting and positioning in certain mechanical assemblies.
They can be useful when the bearing needs additional axial positioning or a specific shaft arrangement.
Small Ball Bearing Sizes
Small ball bearings are available in a broad range of dimensions.
Common bore sizes can include:
3 mm
4 mm
5 mm
6 mm
8 mm
10 mm
12 mm
15 mm
17 mm
20 mm
25 mm
30 mm
The exact classification of a bearing as "small" varies depending on the bearing series and manufacturer.
The three basic dimensions you should check are:
Bore × Outside Diameter × Width
For example, a bearing specified as 8 × 22 × 7 mm generally means:
8 mm bore
22 mm outside diameter
7 mm width
However, these three dimensions don't describe the complete bearing.
The bearing type, internal clearance, seal, material and load rating also need to be considered.
Small Ball Bearing Size Chart
Dimension | What It Means |
Bore diameter | Opening through the inner ring for the shaft |
Outside diameter | Overall diameter of the outer ring |
Width | Axial thickness of the bearing |
Flange diameter | Outside diameter of the flange on applicable bearings |
Flange width | Width of the flange where applicable |
When replacing a bearing, measure all relevant dimensions rather than assuming the bearing number from the shaft diameter.
How to Read Small Ball Bearing Numbers
Bearing designations can contain information about the bearing series and configuration.
Depending on the manufacturer, the designation may indicate:
Bearing series
Bore size
Seal or shield type
Internal clearance
Flange arrangement
Special construction
Material
For example, suffixes may distinguish between:
Open bearings
Shielded bearings
Sealed bearings
Different clearance classes
Because designation systems vary, don't assume that two bearings with similar dimensions are automatically interchangeable.
If possible, provide the complete bearing number when purchasing a replacement.
Small Ball Bearings vs Miniature Bearings
The terms small ball bearing and miniature bearing are often used in similar contexts, but they aren't necessarily identical.
Miniature bearings generally refer to very compact bearings designed for particularly small shafts and space-constrained applications.
Small ball bearings cover a broader size range and can include bearings used in general machinery and compact industrial equipment.
Feature | Miniature Bearings | Small Ball Bearings |
Typical size | Very compact | Small to compact |
Shaft size | Generally very small | Small to moderate |
Load capacity | Usually lower | Wider range |
Applications | Precision and compact equipment | Motors, machinery, automation |
Size range | Narrower | Broader |
The exact terminology can vary between suppliers and manufacturers.
Small Ball Bearings vs Standard Ball Bearings
A small ball bearing is still a ball bearing, but its compact dimensions make it different from larger industrial bearing arrangements.
Feature | Small Ball Bearing | Larger Standard Bearing |
Installation space | Low | Generally greater |
Shaft diameter | Small | Small to very large |
Load capacity | Generally lower | Can be much higher |
Typical applications | Compact machinery | Industrial machinery |
Weight | Low | Higher depending on size |
The right size depends on the machine rather than simply choosing the smallest bearing available.
Applications of Small Ball Bearings
Small ball bearings are used across many industries.
Electric Motors
Small motors frequently use ball bearings to support rotating shafts.
They can be found in:
Cooling fans
Small appliances
Office equipment
Pumps
Compact motors
Electronic equipment
The bearing needs to match the motor's speed, temperature and load.
Fans and Blowers
Small fans require bearings capable of continuous rotation.
A suitable sealed or shielded bearing can help protect the internal components while maintaining smooth operation.
Applications include:
Cooling fans
Ventilation equipment
Electronic cooling systems
Small blowers
Robotics
Small ball bearings can be used in compact robotic mechanisms.
They may support:
Wheels
Rollers
Joints
Shafts
Positioning mechanisms
The bearing should be selected based on the robot's load and movement.
3D Printers
3D printers use bearings in several movement mechanisms.
Small ball bearings can be used for:
Rollers
Guide mechanisms
Drive systems
Extruder assemblies
The exact bearing requirement depends on the printer design.
Pumps
Small pumps can use ball bearings to support rotating components.
The bearing selection needs to consider:
RPM
Load
Temperature
Moisture
Lubrication
Automation Equipment
Automated equipment often contains compact rotating components.
Small ball bearings can be used in:
Rollers
Actuators
Conveyors
Positioning mechanisms
Compact drive systems
Precision Instruments
Instruments can require smooth and controlled rotation while operating within limited space.
Small bearings can be used in:
Measuring equipment
Optical equipment
Laboratory instruments
Small mechanical devices
Office Equipment
Printers, scanners and other office equipment use numerous small rotating components.
Small ball bearings can provide reliable rotation without taking up significant space.
Advantages of Small Ball Bearings
Compact Design
Small dimensions allow them to be integrated into space-constrained machines.
Low Friction
Rolling elements reduce sliding friction between rotating components.
Smooth Operation
A suitable bearing can provide smooth and consistent rotation.
Wide Range of Sizes
Small bearings are available in many bore, outside diameter and width combinations.
Multiple Configurations
They are available as:
Open
Shielded
Sealed
Flanged
Stainless steel
Angular contact
Thrust bearings
Suitable for Many Applications
They can be used in motors, fans, robotics, automation, pumps and instruments.
Limitations of Small Ball Bearings
Small ball bearings also have limitations that should be considered before purchasing.
Lower Load Capacity
A smaller bearing generally cannot handle the same load as a much larger bearing of a similar design.
Sensitive to Installation
Improper installation can damage small bearings, particularly when excessive force is applied.
Contamination
Dust and other contaminants can affect the raceways and rolling elements.
Lubrication Requirements
The correct lubricant and quantity are important for smooth operation and service life.
Shaft Condition Matters
A worn or incorrectly sized shaft can affect bearing fit and performance.
How to Choose the Right Small Ball Bearing
Choosing the correct small ball bearing requires more than knowing the shaft diameter.
Check the Bore Diameter
Start by measuring the shaft.
The bearing bore needs to match the required shaft fit.
Check the Outside Diameter
Make sure the bearing fits within the available housing or mounting space.
Check the Width
Check the available axial space.
A bearing can have the correct bore and outside diameter but still be unsuitable because of its width.
Check the Load
Determine:
Radial load
Axial load
Shock load
Continuous load
Intermittent load
Check Operating Speed
Find out the shaft RPM.
High-speed applications may require specific bearing configurations and lubrication.
Check Temperature
Operating temperature can affect:
Lubricant
Seals
Internal clearance
Bearing materials
Service life
Check the Environment
Consider whether the bearing is exposed to:
Dust
Water
Moisture
Chemicals
Coolant
High temperatures
Check the Seal or Shield
Determine whether the application requires:
Open
Shielded
Sealed
construction.
Check the Required Precision
For precision equipment, robotics and instruments, internal clearance and accuracy may be more important than they are for general machinery.
What to Actually Check Before You Buy
Before buying a small ball bearing, don't simply tell the supplier the shaft size.
Check the Existing Bearing Number
Look for the complete number printed or engraved on the bearing.
If the marking is unclear, take a clear photograph.
Measure the Bearing
If the number isn't available, measure:
Bore
Outside diameter
Width
Flange dimensions, if applicable
Check the Shaft
Inspect the shaft for:
Wear
Damage
Corrosion
Incorrect fit
Surface irregularities
Check Load
Provide an approximate radial and axial load.
Check RPM
Tell the supplier the normal operating speed.
Check the Environment
Mention if the bearing operates in:
Clean conditions
Dusty conditions
Wet environments
Chemical environments
High-temperature conditions
Check the Seal
Decide whether the bearing needs to be open, shielded or sealed.
Check the Available Space
Measure the housing and surrounding components before selecting the bearing.
Small Ball Bearing Maintenance
Proper installation and maintenance can help improve bearing performance.
Keep the Bearing Clean
Prevent unnecessary exposure to dust, dirt and moisture.
Use Suitable Lubrication
Use the appropriate lubricant and quantity for the bearing and application.
Avoid over-lubrication.
Install Carefully
Avoid applying installation force through the rolling elements.
Use appropriate tools and mounting methods.
Check Alignment
The shaft and bearing should be properly aligned.
Misalignment can increase friction and wear.
Monitor Noise and Vibration
Watch for changes in:
Noise
Vibration
Temperature
Rotational resistance
These can indicate wear or damage.
Common Mistakes When Buying Small Ball Bearings
Choosing Only by Shaft Size
The bearing may fit the shaft but have an incompatible outside diameter or width.
Ignoring Operating Speed
A bearing suitable for low-speed operation may not be appropriate for high-speed machinery.
Choosing the Wrong Seal
The wrong sealing arrangement can affect contamination protection and operating performance.
Ignoring Load
Small bearings have specific radial and axial load limits.
Using Excessive Installation Force
Improper mounting can damage the raceways or rolling elements.
Ignoring Lubrication
Incorrect lubricant or excessive grease can affect bearing performance.
Assuming Similar Dimensions Mean Interchangeability
Two bearings with identical dimensions can have different internal clearances, seals, materials and load ratings.
Why Buy Small Ball Bearings From Kashyap Bearing?
When sourcing small ball bearings in Bangalore, the challenge isn't simply finding a bearing that fits the shaft.
The important part is matching the bearing dimensions, load, speed, sealing, material, precision, lubrication and operating environment to the actual application.
At Kashyap Bearing, you can share your existing bearing number, photograph, dimensions, shaft details or machine requirements with the team.
This makes it easier to identify the appropriate small ball bearing rather than selecting one based only on its bore size.
Kashyap Bearing has been serving customers from SP Road, Bangalore since 1987, supplying a broad range of bearings and industrial products.
Whether you need small ball bearings for a motor, fan, pump, robot, automation system, 3D printer, precision instrument or compact industrial machine, providing the actual application details can help narrow down the right product.
If you're unsure whether you need a deep groove, shielded, sealed, flanged, stainless steel, angular contact or thrust ball bearing, speak with the Kashyap Bearing team before purchasing.
The right small ball bearing isn't simply the smallest or cheapest option. It is the one that correctly matches the machine's requirements.
Frequently Asked Questions on Small ball bearings
What are small ball bearings?
Small ball bearings are compact rolling-element bearings that use balls between inner and outer raceways to reduce friction and support rotating shafts.
What are small ball bearings used for?
They are commonly used in motors, fans, pumps, robotics, automation equipment, 3D printers, instruments and compact machinery.
What are the common types of small ball bearings?
Common types include deep groove, shielded, sealed, open, flanged, stainless steel, angular contact and thrust ball bearings.
What sizes are available in small ball bearings?
Small ball bearings are available in a wide range of bore sizes, from very small diameters to larger compact bearing sizes. Exact sizes depend on the bearing series and manufacturer.
What does 8 × 22 × 7 mm mean on a bearing?
These dimensions generally represent an 8 mm bore, 22 mm outside diameter and 7 mm width.
What is the difference between a small ball bearing and a miniature bearing?
Miniature bearings generally refer to very compact bearings for small shafts, while small ball bearings cover a broader range of compact bearing sizes.
Are small ball bearings suitable for high-speed applications?
Certain small ball bearings can operate at high speeds, but the permissible speed depends on the bearing design, seals, lubrication, load and operating conditions.
Should I choose a sealed or shielded bearing?
The choice depends on the environment, speed and lubrication requirements. Sealed bearings generally provide greater protection against contamination, while shielded bearings can offer lower resistance in suitable applications.
Are stainless steel small ball bearings better?
Stainless steel bearings can be advantageous where corrosion resistance is important. The best choice depends on the complete application and operating environment.
How do I identify a small ball bearing?
Check the complete bearing number first. If it isn't available, measure the bore, outside diameter and width and provide a photograph to a bearing supplier.
How long do small ball bearings last?
Bearing life depends on load, speed, lubrication, contamination, alignment, installation, temperature and operating conditions.
Where can I buy small ball bearings in Bangalore?
You can contact Kashyap Bearing on SP Road, Bangalore for small ball bearing requirements. Share the bearing number, dimensions or application details so the appropriate bearing can be identified.
Final Word
Small ball bearings are essential components in compact machines where smooth rotation, low friction and limited installation space are important.
From deep groove and shielded bearings to sealed, flanged, stainless steel, angular contact and thrust bearings, different configurations are available for different applications.
Choosing the right small ball bearing isn't simply about matching the shaft diameter.
Before purchasing, check the bore, outside diameter, width, load, operating speed, temperature, sealing, material, lubrication and available mounting space.
If you're replacing an existing bearing, start with the complete bearing number and dimensions. If you're selecting a bearing for a new application, provide the supplier with the shaft size, load, RPM and operating environment.
And if you're unsure which small ball bearing is right for your application, Kashyap Bearing can help you narrow down the available options. Share your bearing number, dimensions or application requirements with the team before purchasing so you can select a bearing that actually matches your machine rather than choosing one based only on size.
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