Dive summary:

• Chunjo Construction Co. bought a Manitowoc 31000 super-crane – which goes for about $30 million – for its fleet just about the time the global economic downtown turn put the brakes on heavy lifting and lots of other activities.
• The crane was for lifting pressure vessels into place at a gas plant, which is not a strain for its 2,300-metric-ton capacity.
• Now, the crane has put one 280-metric-ton load in place and a second coming in at 480 metric tons, working with as 55-meter boom and a 60-meter luffing jib.

From the article:

Unique to the 31000 is a Variable Position Counterweight—essentially a floating counterweight wagon—that allows the crane to work in tight spaces with minimal ground preparation. ...