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. Spurred on by the demand to build infrastructure bigger, faster and safer, the lifting capacities of the world's largest construction cranes are getting supersized.

For the first time, ENR has assembled a list of the world's top supercranes, which we found hard at work on almost every continent building powerplants, refineries and other large-scale infrastructure and industrial projects.

Ranked by maximum lifting capacity, we found heavy lifters that can pick up at least 2,000 tonnes all the way up to nearly 7,000 tonnes—about the same weight as 78 space shuttles. Some of these machines stand more than 185 meters tall (600 ft), about four times taller than the Statue of Liberty. The price tags on these machines can run to $30 million or more.

Showing these cranes at max capacity reveals little, though. All cranes are essentially levers, so their maximum capacity is rated very close, physically, to the machine. Most construction work happens farther away from the crane, where capacity falls off. Using the manufacturer's load charts, we rate the machines in a more meaningful way by comparing the middle of their load charts. That's where the rubber meets the road.

Taking advice from heavy-lift experts, we plotted out how much each crane can pick up at approximately 61 m (200 ft) away from the crane's center of rotation—also known as the lifting radius—using a roughly 122-m-long (400 ft) boom. We tried to get as "apples to apples" as we could in the comparison. In some cases, we were surprised by what we found.

Brute Strength
The sheer size of supercranes has shot up dramatically in a short time. Nine out of the 13 cranes on our list were introduced within the past six years. In that time, lifting professionals have seen the capacities of supercranes skyrocket to more than 6,800 tonnes from around 2,000 tonnes.

"Ten years ago, 1,000 tons was a pretty sizable crane, and it still is," says Mitch Landry, vice president of Baton Rouge, La.-based Deep South Crane & Rigging. Its VersaCrane model TC-36000/1, built in 2001 and good for 2,268 tonnes (2,500 short tons), ranks at No. 9 on our list.

Since the VersaCrane was built, many supercranes now come in the 3,000-ton category. Much of this muscle power is designed to handle next-generation nuclear powerplants, such as the Westinghouse AP1000, which is put together with hundreds of large modules rather than stick-built. Just a few years ago, project planners were forecasting a resurgence in nuclear construction. After the Fukushima disaster in Japan in 2011, new nuclear power has crept forward much more slowly than expected.

"People built a bunch of really big cranes speculating on the nuclear renaissance here," says Landry. "They designed those cranes to do these big nuclear jobs. Since the Japan problem, it slowed way down."

Ring-type cranes such as the hulking 6,800-tonne Bigge 125D AFRD, the 4,300-tonne ALE AL.SK190 and the 3,200-tonne Mammoet PTC-140/200—first, second and fourth, respectively, on our list—are examples of the newer machines. In the crawler category, we find more recent introductions: the 3,600-tonne Sany SCC36000, the 3,200-tonne Liebherr LR-13000, the 3,200-tonne Terex CC8800-1 TWIN and the 2,300-tonne Manitowoc 31000.