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Miniature Bearings and Instrument Ball Bearings

miniature bearingsAST Bearings has a huge selection of Miniature Bearings and Instrument Series Ball Bearings with over 500 types available. Precision tolerances from ABEC-1 through ABEC-9 are generally available for most miniature products. Typical bore sizes of miniature ball bearings start at 3 mm with an outside diameter a mere 10 mm. Custom-made miniature bearings can have bore sizes as small as 1 mm! 

Many products are available in SV30 special stainless steel material (also in more common 400 and DD type Stainless Steel, 52100 Chrome Steel materials) in both inch and metric dimensions. Other major configurations from AST include:

  • Open miniature ball bearings
  • Open, with extended inner ring miniature ball bearings
  • Shielded miniature ball bearings
  • Shielded, with extended inner ring miniature ball bearings
  • Sealed miniature ball bearings
  • Sealed, with extended inner ring miniature ball bearings
  • Flanged, open miniature ball bearings
  • Flanged, open, with extended inner ring miniature ball bearings
  • Flanged, shielded miniature ball bearings
  • Flanged, shielded, with extended inner ring miniature ball bearings
  • Flanged, sealed miniature ball bearings
  • Flanged, sealed, with extended inner ring miniature ball bearings

Miniature Ball Bearings

Miniature Ball Bearings are small bearings with balls as their rolling elements.  These small bearings have an outside diameter of less than ⅜” (<9.525 mm) or are small bearings with an outside diameter less than or equal to ½” (≤ 12.7 mm) having a ration of outside diameter to inside diameter equal to or less than two.

"Other" Miniature Bearings

AST Bearings specializes in miniature bearings (small bearings) of all kinds and is not limited to just miniature "ball bearings" as described above.  Many times, the category of "miniature" is not defined with other types of bearings, they are simply smaller.  If you are looking for other types of small bearings, you can find them elsewhere on our site in their respective categories including, but not limited to:

Instrument Ball Bearings

The term “Instrument Ball Bearing” is not limited to certain sizes, as with “miniature” ball bearings.  They are precision ball bearings with functional requirements which allow their use in the literal sense of the word.   The tolerances of instrument bearings are always ABEC-5 and higher.  Additionally, they must meet two or more of the following conditions: 

  • Low or uniform starting or running torque
  • Smooth operation or vibration limitations
  • A definite contact angle or preload (or both)
  • Meet high cleanliness standards

If you need help in selecting the best products for your particular application, please remember that design engineering and application assistance are available from AST as part of our value-added services designed to make your job easier.

Choose below to go to either our metric or inch series online catalog and product specifier for Miniature Ball Bearing and Instrument Ball Bearings including free 3D CAD model downloads.

Miniature & Instrument Bearings - Inch Series Catalog & CAD Library»

Miniature & Instrument Bearings - Metric Series Catalog & CAD Library»

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