How are bearings coded?

[Karl H]

I recently needed a low profile rolling box to hold my wonder scrap. I made a angle iron frame the size of an empty wine box and will weld studs to hold bearings for rollers close to the floor. My question: I have one bearing 6201 RS and found more on ebay. The site had over 2000 berings for sale. What does the 6201 stand for? Or the RS? Can some one enlighten me? Thanks -K-

[Spin Doctor]

Am I correct in assuming that the bearing in question is a SKF although it could be an FAG

6-radial bearing, deep groove
2-"light" seies, a 1 is extra light, 3 medium
01-refers to the bore size in mm. Once you get to say a 6204 the bore size in mm is 5 x number. An 04 is 20mm, an 05 25mm, 06 is 30mm etc. Below that I rreally cant recall the ID sizes as I did not deal with them that much
RS-sealed and shielded one side IIRC

Bearing nomenclature can be pretty arcane. Most manufctures have web sites where you can sort through all this stuff

[wierdscience]

The 62xx part refers to the series bearing,they have different race thicknesses,bore sizes and widths depending on 60xx,62xx,63xx,64xx.The 62xx IIRC would mean light conrad type radial ball bearing.

The xx01 refers to the bearing measurements,yours is a 12mm bore,32mm odx10mm thickness.Bearings from 6204 on up the last two digits can be multiplied by five to obtain the metric bore size,example-6205 would be a 25mm bore.

The letters in your case would indicate the seal configuration.

Z = shielded oneside
2Z= shielded two sides
RS= rubber seal oneside
2RS=rubber seal two sides

Then there are other suffixes like
NR= snapring groove on the od
C3=looser than standard internal clearance

So if your bearings used all of these features the part number would be -

6201-2RS-NR-C3

There are many other designations,some standard in industry and many that are proprietary.Sometimes you will se a bearing with what looks like standard markings that is anything but and sometimes it will be a standard bearing with gibberish markings.

[CCWKen]

I get all my general purpose bearings from VXB: http://www.vxb.com/Merchant2/merchant.mvc?Screen=SFNT

He also sells on ebay. He's been adding bearings for the last couple of years and has just about any general purpose and many specialty bearings including angular contact. The prices are cheap and the quality is more than you'd expect for the price. He also has ABEC7 bearings at about 1/3 the price of any other seller. The last batch I got came from Russia and these are great bearings. I think I paid less than $12 (including shipping) for 10 6201-2RS bearings.

No connection, just a satisfied customer.

[motorworks]

chart

To add to W-S excellent reply,
here is a handy chart of fits for housings and shafts fits:

http://www.conweb.com/tblefile/bearfta.shtml

take care
e