In message , Clive
George writes
"tg" wrote in message
...

"Ignoramus13628" wrote in
message ...
On Tue, 2 Jan 2007 18:47:21 -0000, tg wrote:

I have to replace some bearings in a generator I have. I discovered
they are a common size - 6302-2RSH. What I want to know is, do
bearings come in different grades or qualities? Or are they all the
same? I want to replace these bearings with the best I can
get. Thanks for any pointers.

yes, they do come in different grades and qualities. Can you ask the
manufacturer for what they recommend?

I don't trust those girls that answer the phone at the manufacturers.
I'd rather just go for the best I can get - if I can get advice about
what's available. If I ask a local supplier they will only tell me
what they've got, rather than what are the best type.

Define "best". Longest lasting? Smoothest running? For some
applications, the cheapest are the best choice because that's all they
need.


Also, assuming you've decided you want eg the longest lasting ones, how
far up the price/performance curve are you actually prepared to go? If
the normal ones are a fiver,

6203 bearings of the quality you need should cost about a fiver a pair



are you prepared to pay 100 quid for ones which may last twice as long?

This is where you need the experience of a good distributor who knows
their stuff

Manufacturers are not the best people to ask as they will always promote
their product.


(and a side question : I know ball bearings come in different qualities
- do the sealed ones have the same range, or are they rather more
standardised?)


I think 6203-2RSH bearings are sealed on both sides

you could get 6203 Z or ZZ for (single or double) shielded ones

Yes most bearings come in shielded or sealed versions


--
geoff