On the Docks
Steelmaking has long been part of the arc of Cleveland’s history. Today the city is home to the most productive integrated steel facility in the world: ArcelorMittal Cleveland, where 1,800 workers manufacture steel in a process steeped in tradition and controlled with high-tech precision.
With a blast furnace that reaches temperatures of 4,000 degrees Fahrenheit, giant rollers that flatten steel as thin as 1/16th of an inch, and dozens of computers that track the process from start to finish, the ArcelorMittal workers produce almost a ton of steel per worker hour. And that efficiency is what gives this complex along the Cuyahoga River international bragging rights.
In a way, the process of making steel in Cleveland begins in places such as Silver Bay, Minnesota, where iron ore is mined and then loaded on freighters that ply the Great Lakes, navigate the crooked Cuyahoga, and deposit thousands of tons of marble-sized pellets at ArcelorMittal’s riverfront yard, 5.5 miles upriver from Lake Erie.
Like most integrated steel facilities, the complex was built along the water because iron ore had to be transported by ship.
And today ArcelorMittal and its workers – most of them members of the United Steelworkers of America – continue to depend on waterborne transportation to move the millions of tons of iron ore needed annually. Nick Pugliese, raw materials manager, methodically tracks the supply and demand, working with freighter schedulers and shift managers to keep a 100-day supply of iron ore (about 1.1 million tons) close at hand to ensure non-stop production, even during the winter months after one shipping season ends and the new one has yet to begin.
Steelmaking begins when ore from the yard is combined with limestone and coke (created when coal is baked for hours) and loaded into railroad cars that workers guide up a 300-foot high bridge. Once at the top of the bridge the cars are positioned over the top of the blast furnace and their contents dropped into a giant hopper. The scene is rooted in both the past and present. Ray Petz, the raw materials process manager, has spent nearly 40 years making iron and steel, and watching the process evolve. “There are a lot more computers involved now,” he said, “but the ingredients to the recipe are still basically the same.”
Once inside the blast furnace, the iron ore is “smelted,” or melted down and purified in a chemical reaction fueled by air and coke. The limestone removes impurities that rise from the melted iron ore as “slag,” a byproduct later sold for use in cement, concrete and other construction materials. The entire process is monitored on computer screens by workers including 40-year veteran Fareed Hakeem, a senior operating technician. “There is no guesswork to what goes into the furnace and how long it stays in,” he said. “Everything is mapped out down to the minute and the pound.”
Now purified, the molten iron is drawn by gravity to the bottom of the furnace. When enough accumulates, a tap hole that had been plugged with clay is opened to allow the molten iron to escape and run down a refractory-lined trench into rail cars that resemble large torpedoes on wheels with holes cut into the top. As these “bottle cars” leave the blast furnace, traveling along a portion of the complex’s 71-mile short-line railroad system, they glow a bright orange. Their destination: the Basic Oxygen Furnace (BOF), where iron becomes steel.
At the BOF, the bottle cars are rotated so that their contents flow into ladles, which then deposit the molten iron into the furnace, where scrap steel is added and pure oxygen is blown in to reduce the carbon content and remove contaminants. What results is pure, molten steel, which is then poured into another ladle for transport to the continuous caster, where the steel flows into water-cooled copper molds. The steel begins to solidify into a long rectangular shape, and at the bottom of the molding machine, the steel emerges and is cut by operators into individual slabs, each marked with a designated identification number.
The slabs then move by rail to the hot strip mill, a half-mile-long building where steel is reheated to 2,300 degrees Fahrenheit in a special furnace. The 9-inch thick, red-hot slabs are then rolled through a series of mills that reduce and flatten the slab down to a much thinner strip, anywhere from ¾” to 1/16” in thickness. As the steel moves along the hot strip mill’s rollers, it picks up speed, eventually moving at 36 miles an hour. The heat from the process can be felt 30 yards away. “Little bit warm?” joked Debbie Thomas-Ward who worked in the complex for 25 years and now gives tours as a retiree.
Still about 1,200 degrees, the strip of steel is then coiled up and moved into storage for cooling until it is ready to be shipped to a customer or to another department for further processing.
Depending on a customer’s order, the steel coil may move to a final finishing facility where workers roll and treat coils to meet customer specifications, eliminate blemishes, alter the steel’s flexibility, and/or coat it with protective finishes. At the facility’s world-class Hot Dip Galvanizing Line, for example, the long coil of steel is unwound and dipped into a pot of liquid zinc, giving the steel an anti-corrosive coating. When completed, the numbered coils, weighing an average of 22 tons each, are placed in a series of rows to await shipment to companies that will continue the process of transformation by turning the steel coils into new cars, appliances, or other consumer goods.
This is the second in a three-part series. Please visit: www.portofcleveland.com/on-the-docks-4 to read the first part. Next month we will follow the steel to the customer to see what it becomes next.