S638
600 Series Stainless Steel Miniature Bearings
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Part No.
Part No.
S638
Basic Information
Bearing type
Ball
System of measurement
Metric
Construction
Single Row
Weight
28.1 g
Tolerance class
ABEC1
Seal type
Open
For load direction
Radial
Main Dimensions
Bore diameter
8 mm
Bore diameter tolerance
-0.008mm to 0
Outside diameter
28 mm
Outside diameter tolerance
-0.008mm to 0
Width
9 mm
Width tolerance
-0.12mm to 0
Inner Ring Dimensions
Inner ring type
Standard
Ball & Washer Dimensions
Ball diameter
4.762 mm
Ball quantity
7
Performance
Temperature range
-30° to 110 °C
Radial dynamic load rating
785 lbf
Radial static load rating
321 lbf
Limiting speed
25.2 X 1000 rpm
Lubrication
Required
Radial internal clearance
0.002mm to 0.013mm
Radial internal clearance
MC3
Materials
Ring material
Stainless Steel
Ball material
Stainless Steel
Cage material
Stainless Steel
Environment & Compliance
REACH
Compliant
ROHS
Compliant
Technical Drawings
No drawings available at the moment, will be launched soon
Price:
$ 1.35
/ each
In Stock
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S638 Bearing Product Overview & Core Advantages
The S638 is a metric single row deep groove ball bearing engineered for superior performance in radial load applications. Constructed entirely from stainless steel, it offers excellent corrosion resistance and durability. This bearing is characterized by its compact design with an 8 mm bore and a high limiting speed of 25,200 rpm, making it ideal for applications demanding precision, reliability, and efficient operation in various environments. Its ABEC1 tolerance class ensures consistent quality and smooth running.
S638 Bearing Model Code Explained, Specifications & Naming Convention
| Model Segment | Technical Meaning |
|---|---|
| S6 | Series designation indicating a specific size and performance profile for miniature and instrument bearings. |
| 38 | Bore diameter code, corresponding to an 8 mm bore. |
| (No Suffix) | Indicates an open (unsealed) bearing construction. Lubrication is required by the user for operation. |
S638 Bearing Structural Features & Performance Benefits
- All-Stainless-Steel Construction: The rings, balls, and cage are made from stainless steel, providing superior corrosion resistance and making the bearing suitable for harsh or wash-down environments. This also ensures compatibility with a wide temperature range (-30° to 110 °C).
- Deep Groove Raceway: The geometry of the raceway is optimized to support high radial dynamic load ratings (785 lbf) and accommodate minor axial loads, offering versatile performance.
- High-Speed Capability: The design, combined with 7 precision balls and a stainless steel cage, enables a very high limiting speed, which is critical for applications like small spindles and high-speed rotors.
- Standard Internal Clearance (MC3): Features a radial internal clearance of 0.002mm to 0.013mm, which is suitable for most general applications and ensures smooth, low-friction operation.
S638 Bearing Typical Application Areas
- Precision Instruments and Optical Devices
- Small Electric Motors and Fans
- Medical and Dental Equipment
- Food Processing and Packaging Machinery
- RC Models and Drones
- Office Automation Equipment
