Dive Summary:

• When you're talking "big" cranes, don't even bother if the lift capacity is less than 2,000 long tons, and the supercranes these days can reach up to 7,000.
• For as fair a comparison as possible, the list looks at lifting capacities at about 200 feet out from a center of rotation, assuming a 400-foot boom.
• The growth in supercranes has been fast in recent years, with nine of the 13 largest coming on line in the past six years.

From the article:

What is "heavy duty"? A 600-tonne crane is a heavy-duty crane, but in the world of supercranes, heavy is measured in thousands of tons, not hundreds. ...