Bringing a 50,000-ton forging press back to Life


Alcoa's 50,000-Ton forging press in Cleveland is "one of the great machines of American industry." Built in 1955, the "Fifty" broke down three years ago, and Alcoa considered scrapping it. But it's back in operation. Tim Heffernan has the story in The Atlantic.

A forging press is — begging the forgiveness of the engineering gods — essentially a waffle iron for metal. An ingot, usually heated to increase its malleability, is placed on the lower of a pair of dies. The upper die is then gradually forced down against the ingot, and the metal flows to fill both dies and form the intended shape. In this way, extremely complex structures can be created quickly and with minimal waste.

What sets the Fifty apart is its extraordinary scale. Its 14 major structural components, cast in ductile iron, weigh as much as 250 tons each; those yard-thick steel bolts are also 78 feet long; all told, the machine weighs 16 million pounds, and when activated its eight main hydraulic cylinders deliver up to 50,000 tons of compressive force. If the logistics could somehow be worked out, the Fifty could bench-press the battleship Iowa, with 860 tons to spare.

It is this power, combined with amazing precision—its tolerances are measured in thousandths of an inch—that gives the Fifty its far-reaching utility. It has made essential parts for industrial gas turbines, helicopters, and spacecraft. Every manned U.S. military aircraft now flying uses parts forged by the Fifty. So does every commercial aircraft made by Airbus and Boeing.

Iron Giant: One of America's great machines comes back to life.