Can someone smart tell me what are the accepted ratios of marketing
expenses to revenue in the industrial sector? We're talking a big
company, selling heavy equipment, doing about $1 billion in sales.

Marketing budgets usually range from anywhere from as little as 4%
(industrial/manufacturing) to 15% (retail/entertainment) of annual
sales. Each industry has certain ranges, and further more you can find
product specific advertising budgets. I would venture so far as to say
that spending on advertising will not be very high given the sector
you are inquiring about. A good example for you to investigate is auto
manufacturers. A company like Hyundai spent just over 30 million last
year in the US alone. For a company with worldwide profits of tens of
billions of dollars, that is a miniscule amount (and thats the auto
sector!).

It also depends what you clasify as marketing/advertising. The lines
are begining to blur with the advent of interactive sales tools. The
other end of the spectrum is to look at the goals you are trying to
accomplish and figure out what it would take to accomplish that.

A targeted audience like industrial equipment would not need a wide
spread awareness campaign. It could probably reach its target
customers much more efficiently through tradeshows and trade
magazines.

So to answer your question. Personally being in the advertising
industry I like to see a healthy advertising budget to work with. If
you work back from your advertising objectives, and include a
provisional 10-20% of the budget on top, you should have a fairly
accurate estimate.

If you would like to email me your objectives, I can give you a
specific estimate on what I think your budget might be.