Steel, p.18
Steel, page 18
This was difficult to discern. Even the slag, when it came an hour into the casting, was hard for the uninitiated to detect. “Slag is yellower, and not as bright to the eye as iron,” Shupe said, incredulous that I could not see the difference. “It’s important to spot the one from the other, ’cause you can waste a lot of iron if you don’t see it running away with the slag. Or if you have to run slag into a pot and there’s too much iron in it, you’ll burn a hole clean through.”
When the drill is withdrawn from the tap hole, iron bursts into a cast house trench.
In the old days, slag was always poured into a kind of pot, called a thimble even though it was made of cast steel and held twenty tons. Most times at L, slag disposal was more automated. After it rose upstream from the block and began to flow into its own channel, it scurried along to an opening in the cast house wall. Just outside the wall, it cascaded into a square tunnel, where in mid-descent it was sprayed with cold water. The cooled slag coagulated into popcorn-size globs before it hit the tunnel floor. Then the little chunklets flowed with the water through the tunnel a quarter mile to a plant that removed the water, ground the globs to grains, and shipped it to concrete plants.
Molten iron gushes out of the tap hole into a trench.
Meanwhile, the iron took its longest straight run to an area close to a far corner of the cast house. There, at the hole at the end of the trough, it too tumbled, about three feet, falling free into a four-foot oval pool contained in what resembled a double-spouted gravy boat. The area was covered by a fume catcher, as at the skimmer, but there were windows here, too. The iron fell in a steady rhythm, widening and narrowing. The pool of liquid iron frothed and bubbled where the iron hit it, and dozens of sparks flew toward the cover’s walls, flittering like enraged, iridescent blue butterflies and bouncing off the walls in all directions.
The pool of iron was in what was called the tilting runner, which the operator could tilt right or left to one of two tracks and an attendant submarine car. He tilted it left, and the flow of liquid iron arced like soup to the open orifice at the top of the submarine car below. The fall widened as it descended, flaring, losing some droplets, making little smoke and not many sparks, and running at six tons a minute. Inside the twelve-foot-high submarine car, the pink iron rose steadily, showing quarter-size circles of heat that evolved and disappeared. When a car was full, the operator of the tilting runner shifted the angle of the runner and made the liquid iron cascade into a neighboring car.
“An amazing thing about iron and steel,” Gilpin said, looking the high-school principal again, “is to look at the end product, which is as hard as stone, and to think that at one time it flowed thin as water.”
Back at the tap hole, after two hours of casting, sparks began to shoot out, several at first and then more with a vengeance. L was getting dry on this side—it was time to swing this tap hole’s mud gun into position to plug it up. A worker manned the controls, the mud gun moved into the vortex of sparks, and, seemingly against all odds, its nozzle snuffed them. The plunger went silently to work.
Out at the tilting runner, the pool subsided and the golden, sun-bright cascade thinned, then diminished to a dribble. This cast was finished and already men were entering its statistics: seven hundred tons of iron, two hundred tons of slag …
Gilpin and Shupe moved as quick as cats under girders and pipes toward the opposite cast house to help men prepare the tap-hole breakout on the other side.
The molten iron flows past workers on its way to the cast house edge.
During a blast-furnace cast, liquid pig iron flows from the cast-house floor into a submarine car.
On Turning
IRON INTO STEEL
The railway journey from the blast furnace to the steelmaking shop was less than a half mile, but the locomotive and submarine car full of three hundred tons of hot molten pig iron moved no faster than a slow walk; they looked like linked turtles lumbering on uncertain ground. The submarine car, rolling on thirty-two wheels because of the great weight it carried, emitted a stream of rippled air above its orifice, an upside-down cascade of heat. Around this central portal, like an irregular collar of pumice, clung a ragged mess of lumpy, frozen pig-iron drool.
The locomotive clanged as it pulled the submarine car so slowly you could eyeball a blemish on a wheel rim, the tracks sagging as the wheels rotated over them. The pace was deliberate, not only because of the pig iron’s weight but also for the safety of any human or vehicle that might chance to cross the railroad track. The engineer never had his hair ruffled while sticking his head out the cab window unless a wind happened by.
The destination of the pig iron was a building where it was to be purified by fire, to rise in its new incarnation as steel. This was the house of the open hearths, a Karnak Temple born of the industrial age, a mountain ridge of angles and roof and stacks, seemingly designed by an architect wearing seven-league boots. It could only be grasped in part, like an ocean liner eyed from a gangplank. No vantage point revealed its entire breadth or length—retreating a suitable distance failed because other buildings invaded the view.
Trusses and pipe chases entered the open-hearth building from half a dozen directions. Railroad tracks led in at one level, and a gravel road led out from a lower one. Exterior steel stairs and guardrails, all painted yellow, tumbled down the outside walls. Chimneys stood like kiosks all in a row, and a dozen sheds branched off from the main bulk of the building like fractal growths. Into one of these sheds the locomotive dragged the enormously heavy submarine car.
An open hearth shop showing its varied elements, including the charging side and the pouring side, or the “pit.”
Several hundred feet away and twenty feet higher, in the same building, lay the heart of the steelmaking shop, the room with the row of open-hearth furnaces. From the vantage of one end and peering down its length, the room, called the charging side, was boxed counterclockwise from the bottom by the concrete floor, furnace fronts, truss roof, and control wall. These four planes receded with distance, seeming to converge on a far-off vanishing point—a perfect example of artistic perspective. The concrete floor was eighty feet wide and held three pairs of railroad tracks sunk flush along its length. To the right, the fronts of up to a dozen furnaces showed only their seven square doors each, doors that were pierced by six-inch-diameter “wicket holes” spewing fearsome light and sometimes flame. Above was the ceiling of steel trusses, clone after clone of the same truss, one seemingly lapping another and cutting space into countless triangles. To the left was the plane of air-conditioned control rooms, one to a furnace, and panels with gauges and dials.
Open hearths align one after another along the charging side of this building.
Millions of cubic feet of space were contained between these four planes. An ocean liner could have fit in here, or a skyscraper lying prostrate. Pigeons flew around unperturbed. Such rooms are often 1,200 feet or more long; a man walking at a leisurely pace would need five minutes to travel one end to the other. Ten men together, one atop another’s shoulders, could reach the bottoms of the trusses; eight more could reach the peak. All this space would be monotonous except that, at least during the day, it was slashed by shafts of dusty sunrays slicing air from the skylight that ran the length of the peak (Frederick Wood’s inspiration) to the concrete floor, like a lighted spine. These swaths of brightness, after displaying a kind of dexterity by threading the lattice of trusses, took on a solid yellow appearance, the dust and curls of sooty smoke lending them substance.
Master of one such enormity was Jim Garrity, general foreman of Number Four Open Hearth Shop at the Sparrows Point plant. He strolled the great hall like the captain of an old windjammer, up and down, inspecting gauges, checking the source of alarm bells, nodding to an assistant’s suggestion, chewing out a subordinate. “Once, when my kids were small, I took them to the Smithsonian, where there’s a model of this building—or used to be,” he said. “They asked me where in the building I worked. I said all up and down, and they couldn’t believe it. They wanted to know exactly where, and I kept telling them—all up and down. It’s pretty hard on your legs, what with these steel-toed shoes.”
Garrity was fifty-five, claimed Irish descent, and held a Johns Hopkins engineering degree. His grandfather worked in Pittsburgh mills as a puddler, stirring iron through the door of an oven to turn pig iron into wrought iron, considered at the time to be the world’s toughest job. His father started as a door boy in open hearths at age thirteen and grew muscular, like his father before him, from physical labor. “I don’t know what happened to me,” Garrity mused, almost moaned. “I turned out to be a string bean.” But actually he was not. He had good muscles on good bones, stood six feet, and weighed 175 pounds. He looked larger—and fiercer—patrolling the enormous room than in his small foreman’s office, because his hardhat added inches of height and he slung a cocoa-brown wool jacket over his left shoulder like a teenage tough.
His hardhat was white, for management, his full name arced across the front. Clipped to the bill was a pair of blue-tinted glasses shaped like a pince-nez that he could hinge down in front of his eyes when he peered inside a furnace. Below the bill was a band of forehead, flushed from heat, and then a pair of dark-rimmed wraparound safety glasses protecting nut-brown eyes. Supporting them was a nose more flushed than the forehead, and below that a neatly trimmed brown mustache fading to gray. He wore long-sleeved shirts, often striped, over a long-john undershirt, the better to keep steel sparks and heat from reaching his skin. His work pants were dark gray. He kept a pen and pencil in his breast pocket. In his left rear pants pocket, he stuffed the cuffs of a pair of heavy leather gloves; in the right rear pocket was a bent notebook. His wool jacket was flatteringly called fireproof, but its purpose was more to baffle heat and sparks.
“I’m probably a bastard to work for,” he said. “I raise hell a lot. I don’t try to contain myself. I figure I’m the foreman. If people can’t put up with me, people who’ve known me for years now, to hell with ’em. I’m my own boss here. But I want my aides to criticize me. I might say ‘Bullshit’ now, but in an hour, you know I’ll be thinking about it and maybe try a new way.” A little later he said, “I learned a long time ago you can’t be lenient; you can only be fair.”
Garrity’s subordinates were cranemen and furnacemen, about twenty-three to a shift when four of seven furnaces were running, seventy men in all over twenty-four hours. Garrity worked in the shop more than ten hours a day and turned it over to his juniors when he left for home. Still, the phone rang at night and on weekends because the furnaces never shut down.
“It’s a fine line learning how to melt,” he said, using the open-hearth term for turning scrap and molten pig iron into steel that meets customer specifications, “how to tap the furnace, and how to add manganese.” He strolled toward one of the furnaces, one hundred feet long, showing a brick face and seven square doors. “Each batch—we call it a heat—is different and takes different ingredients. Some of what you have to do is laid out, but still you have to think about what the hell you’re doing. It’s not an automatic thing. You have to know the history of the heat. Sometimes it can get real touchy and only experience’ll guide you through. Making steel in an open hearth is more an art than a science.”
He sauntered up to one of the furnace doors—each was water cooled and refractory lined so it wouldn’t melt—and jiggled his left arm. The brown heavy wool jacket on his shoulder jerked forward and unfolded so that, like a matador’s cape, it half lay across the left side of his back and half across the left of his chest. He turned this protected side to the heat of the furnace and with his left hand raised the collar of the jacket up across his nose, lower face, and neck. With his right hand he reached up, flipped down the small blue-tinted lenses, and moved his head near the six-inch wicket hole of the door. His face and hardhat brightened with yellowness. He bobbed and weaved his upper body trying for a parallax view of the flame and molten steel inside, and then his right arm rose, moved slowly toward his back, and halted—a signal to one of his furnacemen about the flame’s location.
Content, he stepped back; there was a locomotive on the way. “We’re very quality conscious,” he said, skin still flushed from the heat, “Very customer oriented. When foreign steel wasn’t such a factor, we used to go our merry way and somebody’d buy everything we made. It’s not that way anymore. We’re very conscientious. It’s a matter of pride. Most men who work with me make as many goals as they can. By goals I mean things like proper chemical composition, time allowed, and so forth. Nobody feels worse than when he misses the goals of a heat.”
Garrity had to make way. One of the heats of which he spoke was in need of pig iron, hauled in by locomotive. It was a full-height electric locomotive striped in yellow-and-black slashes for safety, sporting two flashing red lights, and clanging a bell. The concrete floor trembled underfoot. The train rolled along a track near the control room wall no faster than a man can walk. The engineer, elbow propped on the window frame, poked his head out of a glassless opening and inspected the track. Behind the locomotive, and responsible for the laborious pace, was a flatcar and on it two saddles that supported huge ladles filled with L blast furnace pig iron that had been trundled over in the submarine car; above them, the air seemed to be liquefied, rippling toward the trusses. The ladles are as divorced from the human scale as the room itself. In the main, shaped like any water bucket, they are taller than ranch houses. They seem to have come from an earlier, more heroic age. A football team rushing with shoulder pads lowered would not budge one; a mule team could not pull one. The volume of each was greater than the trailer of a tractor-trailer truck.
After the locomotive had hauled the two ladles to the vicinity of the furnace in need of feeding, it ceased its progress and clanging, and the trembling underfoot stopped. Then there was a faint whir from above, and a huge shadow slid along the floor. It was cast by an overhead crane, a kind of moving steel bridge that stretched from furnace wall to control wall, rolling on rails one hundred feet apart and thirty-five feet up. Dropping below the bridge, close to the control wall, was the operator’s cab; farther out in the room and riding under the bridge itself was a carriage with pulleys, from which descended twenty-four steel cables to a second carriage, also for pulleys. Attached to this lower carriage were two steel J-hooks ten feet high. Upright, the hooks could have pierced the ceiling of a normal room; given the proper tugging power, they probably could have dismembered the Golden Gate Bridge. From down the building, this airborne assemblage rolled, winking out the sun to those below like a solitary summer cloud.
When the overhead crane stopped, the lower carriage and hooks quickly ceased swaying. Then the hooks descended to the level of the ladles and slowly moved toward one of them. They stopped only when their midsections had clanged against the foot-thick sprockets, called trunnions, that protruded from opposite sides of the ladle. The ladle barely wiggled. Above it, the underside of the pulley carriage glowed a pink and vibrated with the furious air. Then, slowly, the cables attached to the pulleys overhead moved through the pulley holes; the J-hooks rose, snared the trunnions from below, and, cables straining, lifted the ladle from its flatcar. The movement was steady—nothing sloshed. Then the cable-suspended system—pulley carriage, hooks, and ladle—rose to twenty feet off the sooty floor and began in the same motion to advance across the room.
When the ladle neared the furnace, it lost speed and descended toward a chute, or runner, that workmen had braced and slanted toward a furnace door. A third, smaller hook dropped from the overhead crane and groped for a lateral bar near the ladle bottom. In the meantime, the furnace door rose in its frame, whose lower level was eighteen inches above the floor, pulling with it a pair of hoses that flushed water through its insides. A thin rectangle of brilliance appeared between door bottom and frame, then seemed to overgrow its confines and hide them behind shimmering, almost painful luminescence. The light was difficult to view directly, but still the door ascended until the golden, incandescent cavern of the furnace fully appeared.
The small hook, having found its grip at the back bottom of the ladle, began to rise, tilting the ladle forward. The angle barely altered before there appeared at the forward, furnace side of the ladle lip a red-yellow tongue, thicker than a camel’s, wider than a hippo’s, reluctantly rolling out into the air. It fell from the ladle with barely a curl, growing longer and longer until its tip smashed against the chute. Then the stream turned a brilliant white, too white to look at, and an explosion of sparks flew back to the ladle top. A great gray cloud, all furious and curling over itself, rolled up like steam escaping from a soup pot when the lid is suddenly lifted. And a great hiss, like gas escaping from a mountaintop, filled the volume of the room. This astounding display, however, was short lived. The sparks tumbled back to the floor, and although others leapt to take their place, these new ones never soared as high as the first. The gray cloud calmed, slowed its ascent, and drifted idly toward the trusses and skylight. The hiss subsided as if it knew its protest was in vain. The flow of liquid metal persisted.
The pig-iron stream lost some of its initial brilliance and added a shade of pink, the color of a very pale pink rose. The liquid was the consistency of cream and so smooth that it practically called to be touched, to have your hands run over and through it. The flow modulated in subtle pulses—wider, thinner, wider, thinner, every dozen seconds. The geyser of sparks, continuing its parabolic flight from the chute, pulsed through higher and lower arcs in rhythm to the stream. The hook at the bottom of the ladle rose steadily, sustaining the pinkish flow. Flames leapt from the furnace through the open door, licked at the stream of liquid metal, and morphed into smoke, which slowed as it rose and meandered toward the trusses. The ladle continued past forty-five degrees, past sixty-five degrees, its rising end never faster than a foot or two per minute. It reached horizontal, and the stream of rosy iron began to thin. At first circular holes appeared in it, then longer elliptical gaps. The hook raised the bottom higher than the lip, but the stream turned to ragged strands. Finally, the ladle gave up its last heavy globs to the chute and drooled on itself a red-yellow drivel. The overhead crane hoisted the ladle away from the furnace and carried it back toward the flatcar, on the way to snare its twin.
