One of America’s great machines comes back to life

TECHNOLOGYMARCH 2012 ATLANTIC MAGAZINE

APPROACHING ALCOA’S 50,000-TON forging press feels a bit like approaching an alp: it starts out incomprehensibly huge and keeps getting incomprehensibly huger. From a distance, the thing dominates the horizon of the hangar-like Cleveland Works facility; as you get nearer, catching glimpses through forests of girders and around cliffs of firebrick, it begins to dominate the air above. But even as you stand at its foot, being told that the eight steel bolts anchoring it are 40 inches thick, calculating in your head that that makes them 10 feet around — even then it’s still a bit out of reach. Only when you climb it, peer down from its sixth-floor summit, and realize that the puny machine next to it is, in fact, its 35,000-ton brother — well, then you finally appreciate the size of the thing. It’s big.

The Fifty, as it’s known in company shorthand, broke down three years ago, and there was talk of retiring it for good. Instead, it was overhauled and is scheduled to resume service early this year. One of the great machines of American industry has been reborn.

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.

The Fifty began its work in 1955, but its history goes back to 1919, when the Treaty of Versailles required Germany to relinquish some of its principal iron-producing regions but allowed it to keep its abundant magnesium reserves. Strong and lightweight, the metal also had one crucial drawback: it could not be worked by hammering, the way iron could. Smack iron, and it bends. Smack magnesium, and it cracks. So of necessity, German engineers developed a new technique for shaping the temperamental metal: press forging. Components made by German forges, using both magnesium and aluminum, helped build the Third Reich’s war machine. But at the end of that conflict, the Soviets took the most powerful forge home with them.

Meanwhile, in the U.S., Rosie the Riveter was still piecing together components out of layers of heavy steel plate. Finding itself suddenly at a disadvantage to the Soviets, the U.S. government decided to do something frankly Soviet in nature: it ordered the construction of a series of massive forges and directed industry in their production and use. The now-forgotten Heavy Press Program, inaugurated in 1950 and completed in 1957, would ultimately result in 10 forges built with taxpayer dollars: four presses (including the Fifty) and six extruders — giant toothpaste tubes squeezing out long, complex metal structures such as wing ribs and missile bodies.

At least eight of the forges are still working today. The Fifty will soon be supplying bulkheads for the Joint Strike Fighter, the U.S. military’s next-generation workhorse. Planned production of the plane extends to at least 2034, when the Fifty will be 79 years old. Alcoa expects it to keep working for at least 30 years beyond that.

Tim Heffernan is a writer in New York. He is currently working on a book about the Heavy Press Program.

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