Above: Shelby Steel bundles and marks cut-to-length sheets to prepare for shipment to customers.
Equipment that can withstand daily abuse and last saves on overhead and headaches
April 2014 - With the spring thaw comes a welcome reprieve from the onslaught of winter that hit much of the U.S. hard this year. Once the slush melts away, an aresenalof potholes emerges to greet drivers like so many tulips. Cities spend significant sums to repair potholes, yet they never seem to stay filled for long. Similarily, one steel mill discovered their levelers’ rolls persistently deteriorated every three to four years. At $40,000, that routine “repair” just became too costly and the company sought a more permanent solution. Eight years later, the company is glad it took that step.
“We need to be able to produce flat sheet and plate and be confident our equipment allows us to be consistent and reliable,” says Mark McClain, president at Shelby Steel Processing, River Rouge, Mich. The company’s leveler contains rolls the metal sheet passes through and backup rolls that put pressure on the rolls. Back up rolls are 3 to 5 inches wide. If the rolls and backup rolls have any spalling (chipping or flaking off the rollssurface), the finished product might come out with a wave or leave marks on the material’s surface.
“After two to three years the backup bearings would be in bad shape and every three to four years, the rolls would need to be completely replaced,” McClain says. “We don’t have time to be worrying about how long rolls have been in our leveler and when their time is up. We needed a low maintenance option.”
Running since 1976, Shelby Steel has survived in the particularly hard-hit Detroit area. “It’s been a tough time in the automotive capital of the world with a lot of smaller companies closing down. Even with the automotive sector recovering, that hasn’t really benefited us because we don’t do a lot of automotive work,” McClain says.
Eager to cut costs and streamline maintenance, McClain turned to Allor Manufacturing Inc./Plesh Industries Inc. for rolls and backup bearings. “We needed the change for longevity’s sake,” McClain says. “We’d keep $40,000 worth of rolls and bearings on the floor just in case we needed to make replacements without losing too much time—that’s money that is better spent elsewhere and now that we’ve got Allor Manufacturing’s rolls, it has been spent better.
“It’s been a tough road for us, we haven’t been thriving,” McClain continues. “But not having to buy new equipment every couple years has helped a lot.”
Normalizing is the norm
The high quality raw materials used to manufacture the rolls and bearings and the normalizing/heat treating process each product goes through is what makes it so durable, says Tony Allor, president of Allor Manufacturing “Normalizing the steel is better for the final surface hardening process. It provides stability and additional strength into the material. It’s a heat treating process so when we do our secondary induction hardening process, it allows our surface hardening to be deeper, harder, stronger and more stable,” he says.
Normalizing is a value-added process and not necessarily a given. “I think a lot of roll manufacturers don’t normalize,” Allor says. “The process allows for the induction hardening to be more stable. We very seldom have spalling issues with our rolls which is a reflection of our heat treating procedures. This process increases the cost of our products, but we think the value-added benefits to our customers makes it worth it.”
Shelby Steel needs to produce flat steel meeting tight specifications and since installing Allor rolls, has had few material rejections. The company operates three cut-to-length lines that can level material as light as 16 gauge up to 1/2 inch thick. “We handle 20 inches to 76 inches in width and level from 30 inches to 540 inches in length. We can handle hot-rolled pickled and oiled, cold-rolled, , galvanized and floor plate,” McClain says. “When you put material out the door, especially today, quality needs to be high and the flatness has got to be right there—panel flat for laser tables. If the material is not panel flat, then we’re in trouble and won’t get any return orders.”
To keep abreast of the latest technology and continue evolving its products, Allor Manufacturing’s people work closely with with in-house engineers. “Our sales team asks customers what equipment needs to be improved and monitors market changes,” Allor says. “If a customer wants to run a new material or has problems with their machines, they come to us for our engineering expertise. We will do a calculated analysis and offer recommendations on equipment upgrades or new equipment requirements.
Older levelers typically have large-diameter rolls with large roll spacing. But with new thinner gauge/higher yield materials, many manufacturers are finding that their levelers no longer level to their satisfaction. “What’s required is a much deeper roll plunge so you can get greater bending,” Allor says. The new high-strength steels have significant shape memory that requires a true 80 percent plastification leveler, he adds. As the yield increases and the gauge decreases, the steel needs to be bent at a tighter radius to achieve consistently leveled flat product.
Allor Manufacturing has worked with customers all over the world, including one client that was having problems leveling thin-gauge armor plate. “It just started out as this idea drawn out on a napkin,” Allor says. “Instead of 7-inch diameter rolls, we reconfigured the leveler using 4 ¾-inch diameter rolls. They went from producing secondary products to better than ¼ tolerance flatness shortly after startup. That was nearly a decade ago and since then our leveling technology has made its way into SSAB, Nucor Steel and others—flat steel that is shipped worldwide.”
The notion of value-added services ends up being a standard expectation when working with Allor Manufacturing. “We try to help our customers solve the problems that keep them up at night,” Allor says.
Purchasing rolls and bearings is Shelby Steel’s first encounter with Allor Manufacturing and the results have been convincing. “My maintenance man said it was one of the best deals we’ve done because we’ve had no issues since the order—he was always busy fixing what we had before,” McClain says. “The specifications from Allor Manufacturing were right on. We’re talking 0.001 of an inch here. Everything was right where it needed to be.” MM