"DIYGUY" wrote in news:1129295051.005458.248910
@g14g2000cwa.googlegroups.com:

... answer me this question. If a caster wheel is rated at a load
carrying capacity (which it is) how is the rating determined? I have a
600# tool I want to put on casters. Does each caster have to be rated
at 600# or can I get four casters, one on each corner, that are each
rated at 150# (or more) load bearing capacity?

Go to mcMaster Carr
http://www.mcmaster.com/

They have 1001 casters in 200 to 600 lb range. Everything you ever wanted
to know about casters are described there.