Secrets to getting a catalog:

Say you have 25 or more employees
Say you are in manufacturing or steelfab, not a hobbyist
Do not say you are an engineer or purchasing agent, say you are
maintenance
Be angry on your second call, or at least say it's your second call,
and ask for a supervisor.

They have (or had, while I was there) this attitude that they only send
catalogs to those they "want" to do business with and meet certain
criteria. Credit doesn't have anything to do with it, and if you wait
for them to notice how much you order it may be a year before they do.