Related topics

Major Step Forward in Steel Casting Measured in Inches

April 30, 1988

PITTSBURGH (AP) _ An industry that weighs its products by the millions of tons and totals its sales in the billions of dollars is measuring one of steelmaking’s most promising technical breakthroughs by the inch.

″The potential is there to shake up this industry,″ analyst Charles Bradford of Merrill Lynch says of a machine that eliminates several major steps in the shaping, or casting, of liquid steel into slabs for further processing.

Like other advances, thin-slab casting has the potential to reduce production costs, including labor. It also gives minimills - smaller scrap- melting steelmakers - an opening to markets dominated by the giant integrated companies that produce finished steel from ore.

The German firm SMS Schloemann-Siemag AG has developed a caster that spits out a ribbon of steel two inches thick - much thinner than the 10-inch-thick strands produced by today’s slab casters.

The eight inches gained may not seem like much. But they’re a world of difference to anyone who ever had to hammer a thick hunk of steel into a strip one-tenth of an inch thick or paid to have that done by the thousands of tons per day as major steelmakers do in conventional hot strip mills.

Roughly half of all the steel produced in the United States passes through hot strip mills, which convert thick slabs of metal into thinner sheets that are used to make such things as car fenders, office furniture and appliances.

SMS says its thin-slab casting process was tested in Europe with good results and offers savings in machinery, energy, time and labor, all of which mean money.

Nucor Corp. hopes to reap those savings at a new plant in Crawfordsville, Ind., where SMS is preparing the first commercial thin-slab caster for a production start next April.

″They’ve achieved things that people didn’t expect them to,″ said Keith Kappmeyer, vice president of research and technology for USX Corp.

USX and Bethlehem Steel Corp. the nation’s No. 1 and No. 3 steelmakers, respectively, aborted a $30 million, federally funded development program after SMS announced its breakthrough more than a year ago.

″We were scooped,″ he said.

Kappmeyer said thin-slab casting has been an ambition of steelmakers since the 19th century, when a patent for a similar caster design was granted to Henry Bessemer, the English engineer whose namesake furnace was the first high-tonnage steelmaking process used by the industry.

Until now, the thinnest slabs possible on a continuous caster were six inches, with 10-inch slabs more common.

″People are struggling to get down ... to six inches. So to go from 10 inches to two inches is enormous. It is an unknown territory,,″ said Herbert Fastert, president of the German company’s Montvale, N.J.-based subsidiary, SMS Concast Inc.

The limiting factor had been the caster’s water-cooled copper mold, which shapes the molten steel while cooling the surface enough to hold the shape as the metal moves through continuously. In conventional molds, the intake and output openings are the same size.

The ″ingenious idea″ that SMS engineers had was to use a funnel-shaped mold and to put the steel through at faster rate, 250 inches per minute compared to 60 inches in conventional molds, Fastert said.

″The principle is so simple people said it’s crazy,″ he said. ″It is crazy to suggest you do it in a funnel, because when it gets stuck in the funnel and you pull it out and it breaks, all your steel will run out. You lose three or four tons of liquid steel all over your equipment.

″If you do it fast enough, you can do what at slow speed you could never achieve,″ Fastert said. ″I liken it to water skiiing. If you don’t have the courage to go fast, you’ll never get out of the water.″

Nucor’s interest in the new caster fits the style of the lean and aggressive Charlotte, N.C., company, one of the efficient minimill operators that helped rebuff cheap imports of concrete reinforcing bar and other low- value products.

″We’ve always made an effort to use the latest technology,″ said Nucor Chairman Kenneth Iverson.

The innovative caster will help Nucor break into the market for flat-rolled steel sheet, which had been the province of integrated companies whose excess capacity led to cut-throat competition through most of this decade.

″When you go into a market that has overcapacity, you’ve got to be prepared to push somebody else out,″ Iverson said. ″You’ve got to have a competitive advantage.″

The Crawfordsville, Ind., caster, Nucor’s edge, will be coupled with a streamlined mill to produce flat-rolled steel. The plant will cost $230 million ″compared to a billion for an integrated hot strip mill,″ he said.

SMS says the quality of its thin-cast strip meets or beats conventionally produced steel, and Iverson said he expects to lop $50 to $75 off the average price of $400 per ton for strip.

″This is the first time that a minimill has been built for flat-rolled products,″ Iverson said. ″There’s just a whole group of people who are looking at it and watching us.″

The entry of a minimill operator into flat-rolled steel may not faze some of the giants of the industry, but lesser competitors could be challenged, analysts say.

″None of this is going to be a problem for the first few years, but I know six people who want to buy the second″ SMS caster, Bradford said.

End Adv Weekend Editions April 30-May 1

Update hourly