ABEC scale

The ABEC scale is an industry accepted standard for the tolerances of a ball bearing. It was developed by the Annular Bearing Engineering Committee (ABEC) of the American Bearing Manufacturers Association (ABMA). The ABEC scale is designed to provide bearing manufacturers dimensional specifications that meet the standards of precision bearings in a specified class. Manufacturers who produce equipment that require bearings must also know the dimensional tolerances to design parts that will accommodate a bearing.

There are five classes from largest to smallest tolerances: 1, 3, 5, 7, 9. The higher ABEC classes provide better precision, efficiency, and the possibility of greater speed capabilities, but do not necessarily allow the components to spin faster. The ABEC rating does not specify many critical factors, such as load handling capabilities, ball precision, materials, material Rockwell hardness, degree of ball and raceway polishing, noise, vibration, and lubricant. Due to these factors, an ABEC 3 classified bearing could perform better than an ABEC 7 bearing. Bearings not conforming to at least ABEC 1 cannot be classified as precision bearings as their tolerances are too loose.

The scale also works as a guide for consumers to make informed decisions about the type of bearing they desire, despite not knowing factors related to materials, manufacturing, and performance.

High rated bearings are intended for precision applications like aircraft instruments or surgical equipment. Lower graded bearings are intended for the vast majority of applications such as vehicles, mechanical hobbies, skates, skateboards, fishing reels and industrial machinery. High ABEC rated bearings allow optimal performance of critical applications requiring very high RPM and smooth operation.

ISO's equivalent standard is ISO 492.[1][2] The German equivalent is DIN 620. The Japanese equivalent is JIS B1514[3].

ABEC ISO 492 DIN 620 JIS B1514
ABEC 1normal
class 6X		 P0 Class 0
ABEC 3class 6 P6 Class 6
ABEC 5class 5 P5 Class 5
ABEC 7class 4 P4 Class 4
ABEC 9class 2 P2 Class 2

Bearing Tolerance Illustrated

For a graphical representation of the bearing tolerance differences by grade,[4] please see the table. The table shows the actual allowable deviations, in micrometers (μm), from nominal for a 20 mm inner diameter bearing. As you can see, an ABEC 7 bearing only has a 5 μm (Greek letter Mu) tolerance window, whereas an ABEC 1 has double that at 10 μm. Please see the tables and PDF's above for more specific precision bearing tolerancing.

gollark: git would really not be a good choice:- the flat-hierarchy thing would probably be problematic, I hear filesystems do not like directories with tons of files in them- would have to deal with git's bad CLI- would have to incur the significant overhead of running an external process to do stuff- no easy way to do on-disk encryption (for SQLite, I can swap in SQLCipher easily)- external state (in git) means more complex code still
gollark: Now, I *could* overhaul it to use text files and git, but that would be extremely annoying.
gollark: Fossil?
gollark: This uses SQLite as a data storage backend.
gollark: ... no?

References
  1. ISO 492:2014 – Rolling bearings – Radial bearings – Geometrical product specifications (GPS) and tolerance values. Iso.org (2014-09). Retrieved on 2017-10-11.
  2. Bearing Precision Comparison. Minibearings.com.au. Retrieved on 2012-08-12.
  3. "General Bearing Technical Information - Technical Support". www.hambini.com. Retrieved 2019-11-19.
  4. differences between the ABEC classes provided by GMN Bearings

Bibliography
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.