The cage has the task of keeping the balls in the ball bearing separated from each other around the pitch circle of the bearing. In order to find the optimum solution for any ball bearing, myonic has developed many different cage designs. They differ both in their construction and in the material.
Key Functions of Ball Cages
Uniform Spacing
Keeps balls evenly distributed, prevents collision
Guide Motion
Ensures correct ball running trajectory
Reduce Friction
Lowers operating resistance and heat generation
Lubricant Distribution
Helps distribute lubricant evenly
Cage Selection Considerations
There is no cage that meets all conceivable requirements. The following requirements must be taken into account when selecting the most suitable cage:
- Starting and running friction torque
- Speeds
- Acceleration and deceleration
- Operating temperature
- Type and quantity of lubricant
- Ambient conditions during use (vacuum, chemicals, etc.)
- Noise emission requirements
- External vibrations
- Self-lubricating requirements
Metallic Cages
Standard Model 480 - Two-Piece Tightly Crimped Steel Cage
This two-piece cage is manufactured using a stamping process. It is sufficient for most applications where there are no extreme requirements. It can be used where no low starting or running friction torque are required, in applications with medium or high speeds, or if sufficient lubrication is guaranteed.
Standard steel ribbon cage (Model 480)
This type of cage is supplied as standard with most miniature radial ball bearings when contamination, misalignment and high acceleration/deceleration are not important. If the cage is to be used with a speed characteristic value n x Dm above 400,000 (n = speed in rpm; Dm = pitch circle in mm), please consult our application engineers.
| Characteristic | Specification |
|---|---|
| Material | Cold-rolled steel sheet |
| Manufacturing Process | Precision stamping |
| Max Speed (n x Dm) | ≤ 400,000 |
| Friction Characteristics | Standard |
| Operating Temperature | -20°C to +120°C |
| Applications | Standard industrial applications |
Model 48 - Loosely Crimped Two-Piece Steel Cage for Low Frictional Torques
This cage is manufactured using a stamping process, is very light and prevents sticking. myonic has developed the "48" model especially for applications requiring low frictional torque or relatively low speeds.
Low friction steel ribbon cage (Model 48)
Improvements compared to Standard Model 480:
- Extremely low starting friction torque
- High sensitivity, suitable for instruments
- Note: For speeds above 5,000 rpm, please contact our technical department
Two-Part Crimped Steel Cage with Coating
For cases where conventional lubricants are not suitable, both the two-piece standard cage model "480" and model "48" can be coated with a fine layer of Teflon or other materials that have a self-lubricating effect. Teflon-coated cages are used for very long storage times, in instruments that work in a vacuum, and in optical systems.
It is strongly recommended to consult our technical office before choosing coated cages and/or to carry out practical tests with the end application.
Synthetic Material Cages
For high-speed and ultra-high-speed applications, myonic offers various synthetic material cages, manufactured by precision machining or injection molding.
High-speed cage (Model 23)
Angular contact high-speed cage (Model 25)
Two-piece crimped steel cage
Model 23 - Crown or Comb Cage for High Speed Applications
This ball cage in the form of a crown or a comb is machined or injection-molded from various synthetic materials. If the correct material is selected, this model can be supplied either oil-impregnated for a longer service life or completely dry if the ambient conditions do not permit lubrication with standard lubricants.
The ball cage model "23" is used in myonic ball bearings for applications with speed characteristics n x Dm of up to 1.3 million (n = speed in rpm; Dm = pitch circle in mm). For even higher rated speed values, we recommend consulting our application engineers.
Model 25 - Solid One-Piece Cage for Angular Contact Ball Bearings
This is a solid one-piece cage that is machined or injection molded. The myonic cage "25" is specially designed for the RA and RKA series angular contact ball bearings. This ball cage can be supplied in oil-impregnated form to increase the service life in the event of insufficient lubrication.
The ball pockets are designed so that the inner ring of the ball bearing can be removed without the balls falling out. This means that the two rings can be installed separately if necessary. The ball cage model "25" is used in myonic ball bearings for applications with speed characteristics n x Dm of up to 1.5 million (n = speed in 1/min; Dm = pitch circle in mm).
Model 27 - High-Speed Cage with Through-Drilled Ball Pockets
This ball cage is very similar to model "25", with the exception that the ball pockets are drilled through. When the inner ring is removed, the balls are not held in place with this design. The advantage is the lower frictional torque compared to the "25" model.
Model "27" is used in myonic ball bearings for applications where speed characteristics n x Dm of up to 2.4 million (n = speed in 1/min; Dm = pitch circle in mm) occur. For even higher speed characteristics, we recommend consulting our applications engineers.
High-Speed and Special Material Cage Comparison
| Model | Material | Manufacturing Process | Max Speed (n x Dm) | Characteristics |
|---|---|---|---|---|
| 27 | High-performance synthetics (e.g., PAI/PI) | Precision machining (drilled) | ≤ 2,400,000 | Ultra-low friction, designed for very high speeds |
| 25 | Synthetic materials (e.g., PEEK/PPS) | Injection molding | ≤ 1,500,000 | One-piece design, suitable for flanged bearings |
| 23 | Synthetic materials (e.g., PEEK) | Machined | ≤ 1,300,000 | Can be oil-impregnated (vacuum impregnation) |
| Hgw | Phenolic resin (hard fabric) | Machined | ≤ 1,000,000 | Traditional high-speed material, good oil absorption, smooth operation |
| PTFE | Pure Teflon (solid) | Machined | Low speed | Self-lubricating, corrosion resistant, suitable for vacuum/cleanroom |
Advantages of Synthetic Cages
Ultra-Low Friction
Self-lubricating properties, extremely low friction coefficient
High-Speed Performance
Lightweight materials, low centrifugal force
Non-Magnetic
Does not affect magnetic measurement environments
Corrosion Resistant
Excellent chemical stability
Materials for Cages
myonic can offer many synthetic materials for cages in addition to metallic materials. Some examples:
- Corrosion-resistant steel
- Laminated fabric
- PAI (Polyamide-imide)
- PI (Polyimide)
- PEEK (Polyetheretherketone)
- PA (Polyamide)
- PTFE (Polytetrafluoroethylene)
- POM (Polyoxymethylene)
- Laminated paper
Each of these materials has its advantages, depending on the area of application, lubrication and operating environment. We strongly recommend that you contact your nearest myonic sales office or our applications engineers for the best choice of cage material.
Special Coatings
For special application environments, myonic offers Teflon-coated cages.
Teflon Coating Application Scenarios
| Application Environment | Coating Advantage | Typical Cases |
|---|---|---|
| Vacuum Environment | Low outgassing rate, prevents contamination | Semiconductor manufacturing, aerospace equipment |
| Dry Running | Self-lubricating properties, reduced wear | Medical devices, food processing |
| Chemical Corrosion | Excellent chemical resistance | Chemical equipment, laboratory instruments |
| Cryogenic | Maintains performance at -200°C | Cryogenic freezing equipment |
Customized Cage Designs
If none of the standard cages listed are suitable for the customer's requirements, myonic can also manufacture special designs completely according to customer specifications. Our research and development department is constantly testing new innovative materials and cage designs which offer first class performance.
Please contact our sales engineers or technicians who will be happy to help you select the best solution for your application problem.
Cage Selection Guide
| Speed Range (n x Dm) | Recommended Cage | Application Scenarios |
|---|---|---|
| < 600,000 | 480 (Standard steel) | General industrial applications, motors, pumps |
| 600,000 - 800,000 | 48 (Low friction steel) | High-speed motorized spindles, turbines |
| 800,000 - 1,200,000 | 27 (PA) | High-speed spindles, dental handpieces |
| 1,200,000 - 1,800,000 | 25 (PPS) | Ultra-high-speed spindles, grinding machines |
| > 1,800,000 | 23 (PEEK) | Extreme high-speed spindles, aerospace applications |
Important Notes:
- n x Dm value = RPM x bearing pitch circle diameter (mm)
- Actual applications must also consider load, lubrication, and temperature factors
- Consult the myonic technical team to confirm the optimal configuration