myonic Designation System for Ball Bearings
myonic uses a standardized designation system to identify all the technical characteristics of a bearing. The following example illustrates the complete designation structure:
UL 3006 .9f 1000
Example: design UL, dimension code 3006 (in 1/32 inch units), X arrangement, preload 10 N
Official Designation Example Table A — Basic / Material / Closure / Duplex / Cage / Tolerance / Radial Clearance
Source: myonic official General information page.
| Basic designation | Material | One-sided closure | Duplex | Cage | Tolerance | Radial clearance |
|---|---|---|---|---|---|---|
| UL 3006 | X | — | — | -48 | -A5P | -6/10 |
| ULKZ 4008 | X | .1c | — | — | -A7P | — |
| RKF 310 | X | .1v | — | — | -P5P | -11/20 |
| R 6190 | X | — | — | -237HG | -P4P | -2/5 |
| ULKU 8012 | X | — | — | -48 | -A9P | -2/10 |
| RA 4012 | X | — | — | -257HP | -A7P | — |
| R 5160 | X | — | .9d/1000 | — | — | -16/20 |
Notes: UL = design / 3006 = nominal bore and outside diameter in 1/32 inch (metric series in mm) / X = 1.4125 (AISI 440 C) stainless steel / .1 = one-sided closure, .1c = flange side, .1v = opposite the flange / .9f = X, .9d = O, .9t = Tandem, 1000 = preload 10 N / cage design, number of balls, material / tolerance per ISO or ABEC / radial clearance lower/upper limit in µm, standard = 6/15.
Official Designation Example Table B — Contact Angle / Noise / Frictional Torque / Dimension Group / Special Instructions / Lubrication
| Basic designation | Contact angle | Noise | Frictional torque | Dimension group | Special instructions | Lubrication |
|---|---|---|---|---|---|---|
| UL 3006 | — | — | 10/75D | -S2 | -J... | -L23 |
| ULKZ 4008 | — | — | — | — | — | -G48 |
| RKF 310 | — | -10/174 | — | — | — | -G48/20 |
| R 6190 | — | — | — | -SB4/0C | — | -G21/…mg |
| ULKU 8012 | — | — | — | — | -J... | -L25 |
| RA 4012 | -20/25° | — | — | — | — | -L23 |
| R 5160 | — | — | — | -S4/BB | -J... | -L23 |
Notes: contact angle lower/upper in degrees, standard = 17/22° / Noise: 10 ≥ limit value, 174 = measurement device / Frictional torque: 10 ≥ limit value in µNm, 75 = axial testing force in cN, D = running friction moment / dimension group classification / -J... refers to internal company regulations for requirements not expressible by prior suffixes / L = oil, G = grease; e.g. G5/20 = grease G5 with 20% dispersion; G18/…mg = grease G18 with dosage in mg.
Designation Code Description
| Position | Code Example | Description |
|---|---|---|
| Design type | UL | Basic model / design type (UL series) |
| Dimension code | 3006 | Nominal bore and outside diameter, in units of 1/32 inch; 3006 means bore 3/32″ ≈ 2.381 mm, outside diameter 6/32″ ≈ 4.763 mm |
| Duplex arrangement | .9f | .9f = X arrangement / .9d = O arrangement / .9t = Tandem |
| Preload | 1000 | Preload 10 N |
Contact Angle and Radial Clearance (Two Independent Parameters)
Per the official myonic General information page, contact angle and radial clearance are two independent parameters, each expressed as "lower/upper" (contact angle in degrees, radial clearance in µm); the official page does not provide a mapping between them.
| Parameter | Standard value | Notation | Official reference |
|---|---|---|---|
| Contact angle | 17/22° (standard) | lower / upper (degrees) | Bearing clearance and contact angle |
| Radial clearance | 6/15 (standard) | lower / upper (µm) | Bearing clearance and contact angle |
Complete Reference Table of Common Suffix Codes
| Category | Code | Description |
|---|---|---|
| Seals | V | Dust cover (non-contact shield) |
| Z | Metal shield | |
| X | Stamped stainless-steel shield (one of myonic's standard closures) | |
| F | Filmoseal (capillary-film non-contact seal) | |
| .1 | One-sided closure | |
| .1c | One-sided closure (flange side) | |
| .1v | One-sided closure (side opposite the flange) | |
| Duplex arrangement | .9f | X arrangement (face-to-face) |
| .9d | O arrangement (back-to-back) | |
| .9t | Tandem arrangement | |
| Tolerance class | P2 / A9P | ISO 2 / ABEC 9P (ultra precision) |
| P4P / A7P | ISO 4 / ABEC 7P (high precision) | |
| P5P / A5P | ISO 5 / ABEC 5P (precision) | |
| P6 / A3 | ISO 6 / ABEC 3 (standard) | |
| No suffix / A1 | ISO 0 / ABEC 1 (general) | |
| Dimension group classification | S4 | Both bore and outside diameter grouped in 1.25 µm |
| S2 | Both bore and outside diameter grouped in 2.5 µm | |
| SN4 | Bore only grouped in 1.25 µm | |
| SN2 | Bore only grouped in 2.5 µm | |
| SB4 | Outside diameter only grouped in 1.25 µm | |
| SB2 | Outside diameter only grouped in 2.5 µm | |
| SN4-SB2 | Bore 1.25 µm + outside diameter 2.5 µm | |
| SN2-SB4 | Bore 2.5 µm + outside diameter 1.25 µm | |
| Contact angle | 17/22° (standard) | lower/upper (degrees); standard contact angle |
| a/b° | lower a° / upper b°; non-standard combinations available on request | |
| Radial clearance | 6/15 (standard) | lower/upper (µm); standard radial clearance |
| a/b | lower a / upper b (µm); non-standard combinations available on request |
Designation Examples Explained
Official example: UL 3006 .9f 1000
- UL = design type (basic model)
- 3006 = dimension code (in 1/32 inch units; metric series in mm)
- .9f = X arrangement (matched pair, face-to-face)
- 1000 = preload 10 N
When ordering, please refer to Official Designation Example Table A and Table B above for each suffix code; for example, the full designation for the UL 3006 model includes material X, cage -48, tolerance -A5P, radial clearance -6/10, friction torque 10/75D, grouping -S2, special -J..., and lubrication -L23 (see the corresponding columns in Table A/B).
Cleanliness is Crucial for Miniature Ball Bearings
Cleanliness is a critical factor in ensuring proper functioning of miniature ball bearings. Even minute contaminants can severely affect bearing performance and service life. myonic implements strict cleanliness controls throughout the entire production and packaging process.
How myonic Fulfills Strict Cleanliness Requirements
Environment Control
Complete temperature and humidity control as well as air filtration in all production areas
Ultrasonic Cleaning
Ultrasonic cleaning of components between the individual production steps
Special Cleaning Process
Cleaning the components using special processes developed by myonic immediately before assembly
Clean Room Assembly
Assembly of ball bearings in ISO 7 clean rooms under ISO 5 laminar flow boxes
Strict Personnel Rules
Strict adherence to cleanroom processes by all personnel working there
Final Product Cleaning
Cleaning of the fully assembled product using processes specially developed and optimized by myonic for miniature ball bearings
Filtered Lubricants
Use of special filtered lubricants
Hermetically Sealed Packaging
Packaging of the finished ball bearings in clean and hermetically sealed bags or tubes
This enables myonic to supply customers with ball bearings with the highest possible degree of cleanliness. In order to guarantee this condition until the ball bearing is installed, our customers should also exercise this high degree of care.
Customer Installation and Handling Guidelines
To maintain the highest cleanliness of myonic bearings, we recommend observing the following instructions:
Installation Environment Requirements
| Item | Requirement |
|---|---|
| Adjacent Component Tolerances | All adjacent components must be manufactured to the recommended tolerances in this catalog |
| Surface Quality | Component surfaces must meet the application requirements and be free of burrs, loose particles, swarf, rust, dirt and similar |
| Cleaning Location | Cleaning of adjacent components should be carried out outside the assembly area, ensuring parts are not soiled again during transportation |
| Dedicated Installation Area | Bearings should be installed in a specially equipped area that is separated from other rooms |
| Environment Conditions | The area should meet clean room requirements as far as possible, with a dust-free atmosphere and temperature/humidity control |
| No Mechanical Processing | Mechanical processing steps must not take place in the same room |
Personnel Operating Guidelines
| Guideline | Detailed Requirement |
|---|---|
| Dress Code | Must wear lint-free gloves and work suits (such as dust coats and overcoats), and use lint-free hoods |
| Strictly Prohibited | Smoking, eating, wearing make-up and similar are strictly prohibited in the cleanroom |
| Package Opening Timing | Bearings should only be removed from protective packaging immediately before installation |
| Quantity Control | If a package contains more than one bearing, do not remove more than the immediately required number |
| Handling Tools | Bearings should be handled with tweezers or other special tools |
| No Direct Contact | High-precision miniature bearings must never be touched directly with the fingers |
| Protective Gear | Recommend wearing lint-free, abrasion-free finger cots or gloves |
Important Note:
The higher the demands placed on the bearings, the more strictly these recommendations must be observed.
myonic ISO Certifications
myonic holds the following international certifications, ensuring that product quality and environmental management meet the highest standards:
ISO 9001:2015
ISO 14001:2015
Certification documents can be downloaded directly from the official website (German, English and Czech PDF versions, see product-myonic.com/en/general-technical-basics/).
Material for Ball Bearing Races
myonic offers a variety of material options to meet the requirements of different application environments. The right choice of material is crucial for optimum function in the end application.
Material Comparison Table
| Suffix | Short Name | Availability | DIN | AISI | AMS | SAE | Corrosion Resistance | Smooth Running | Hardness |
|---|---|---|---|---|---|---|---|---|---|
| X | X105CrMo17 | Standard | 1.4125 | 440 C | 5618 | - | Very good | Good | 61 HRC |
| XG | X65Cr13 | On request | 1.4037 | 420D | - | - | Good | Good | 60 HRC |
| XA | X30CrMoN15-1 | On request | 1.4108 | - | 5898 | - | Excellent | Good | > 58 HRC |
| V | 100Cr6 | On request | 1.3505 | - | 6444 | 52100 | No | Very good | 62 HRC |
Material Properties Description
| Material Suffix | Properties | Recommended Applications |
|---|---|---|
| X (Standard) | X105CrMo17 - This is the standard material, mainly used where corrosion resistance is required. It has a high degree of corrosion resistance and, after heat treatment, reaches a hardness of 61 HRC. | General purpose, corrosion-resistant environments |
| XG | X65Cr13 - Introduced to round off the range of corrosion-resistant bearing steels. The low carbon content gives a lower hardness than 440C steel, but still sufficient for rolling bearings. The 13% chromium content meets corrosion resistance requirements. | Moderate corrosion environments |
| XA | X30CrMoN15-1 - Stainless steel with a large proportion of nitrogen, producing a special microstructure with improved macromechanical properties, particularly hot hardness, elasticity, flexural strength and elongation at break. | Please consult myonic application engineers |
| V | 100Cr6 - The most frequently used material for bearings of all sizes. Complies with the AISI 52100 standard and, after heat treatment, ensures a good, uniform microstructure with a hardness of 62 HRC. | High precision, dry environments (no corrosion resistance required) |
Material Selection Advice:
Please contact our application engineers, who will recommend the steel grade best suited to your specific application. Our engineers will provide the right solution for applications with the highest demands on ball bearings. Steel grades from the list above and/or special materials can be used. Other materials are available on request.