How one mill competes
Burns Harbor, Ind.
AT is 150 degrees: hot enough to make Death Valley feel like the inside of an ice chest. But Bill Crosslin, covered with asbestos shielding from head to toe, walks into the heat and sticks a 20-foot thermometer into a caldron of molten steel. Mr. Crosslin is checking the temperature in a mixing bowl filled with 65 tons of metal heated to a searing 2,816 degrees F.
Crosslin's job at this Bethlehem Steel mill is to control the inferno, ensuring that each slab of steel comes out exactly alike, thus meeting the quality demands of customers building everything from automobiles to dishwashers.
Twenty yards away in an air-conditioned control room, Dale Valett watches a computer monitor that emits a steady stream of data on the molten process outside. With a few clicks on a keyboard, he directs the path of 300 tons of liquid steel brewing in a ladle.
Both men are part of a team managing a continuous caster that saves Bethlehem Steel between $100 million and $160 million a year compared with less efficient steelmaking methods. ``Steelmaking has gone from an art to a science,'' says Joe Emig, the plant's general manager.
That's not the way it was 10 years ago at Burns Harbor. Before the continuous caster was installed, ``We needed people with little education and a strong back,'' says Walter Bargeron, a senior manager. ``It was rough and dirty work.''
It was also time-consuming. Steel was poured into cast-iron molds to form ingots, which took 12 hours to solidify. Once cold, they were thrown back into a furnace and heated for 20 hours until they glowed red hot and could be made into a slab. The slab itself had blemishes on it, requiring individual grooming.
That's not the way it is today.
The high-tech process is most noticeable in a $14 million investment Bethlehem has made in computerizing the way it adds alloys and other agents to a 300-ton ladle, which is a mixing bowl for molten steel. By computerizing the ladle treatment, Bethlehem can ``control the steelmaking to a gnat's eyelash,'' says assistant superintendent Fred Rorick.
From the ladle, the steel is poured into a smaller, 65-ton vessel called a tundish, where it is kept at Dante-esque temperatures until it can be poured into the mill's new $250 million continuous caster. The eight-story, football-field-size caster looks like a roller coaster. The caster forms the molten steel directly into 20-ton slabs.
The slabs eject from the caster like soda cans from a vending machine. Glowing red at 2,400 degrees, they are squeezed into thin coils used to make just about everything.
The squeezing process takes three miles in eight separate buildings, with hardly a worker in sight. Instead, workers monitor multiple sets of computer screens with high-quality color graphics. As cranes swing around the ladles of molten steel, the computers track the progress. Electronic sensors warn operators of temperature and pressure changes. The computer helps operators in the sorting and hauling process.
The yield and quality of steel produced by this process are eye-opening. With the ingot method, between 80 and 86 percent of the raw steel produced could be made into coils. With the continuous caster, 95 to 97 percent is usable.
But it is more than machinery that is revolutionizing steel production at Burns Harbor. Instead, general manager Emig notes, ``We have a new philosophy of continuous improvement.''
For example, 80 percent of the hourly work force is trained in statistical process controls. This method of production, used widely by the Japanese, employs statistics to determine when manufacturing processes have actually changed.
Thus the caster operator, Mr. Valett, is constantly watching the computer screen as temperatures, flow rates, and pressures change in the furnaces outside his window. ``We are trying to reduce variability,'' he says. When the statistics start changing in an unusual pattern, he knows it is time to check the recipe before a slab with a defect is cast.
This quality-conscious attitude is impressed on Crosslin and Valett everywhere they turn. Company note pads, calendars, banners, and posters are all stamped with the ``Continuous Improvement'' motto.
The new machinery and attitude are paying off. Emig says defects are down 50 percent over the past two years. Even more important, customers such as General Motors have upgraded their standards so they can compete with the Japanese auto companies. So far they like the results from Burns Harbor. The number of coils rejected by customers is down 10 to 20 percent since the new process started.
Reflecting the new attitude, Emig says: ``We can still improve.''