Sorting scrap iron and steel is done daily at all scrapyards, but a select few have raised the task almost to the level of an art form the yards that ship ferrous scrap to iron foundries.
The castings makers are among the fussiest scrap buyers. They're not happy with steel mill grade busheling; it has to be black busheling without a zinc coating and many of the tramp elements that steelmakers might deem tolerable for their furnaces. Shredded not only must be low in copper (0.20 percent, much like the material that steel mills buy), but also low in other elements, like manganese and chrome.
Mark Lasky, president/owner of Sadoff & Rudoy Industries LLP, Fond du Lac, Wis., said his company and a few others like it have carved out a niche in the foundry scrap market by sorting carefully, keeping non-conforming material out and giving foundries a tight specification package for the melt. That puts more value-added into the scrap.
Foundries also are very sensitive to variations in chemistry from using different types of obsolete plate and structural scrap, he said. "They need the consistency. We work with hand-held spectrometers, but we find we have to shoot these samples more often because the mix changes. We don't want our consumers to tell us that. We want to know that before we ship it."
Foundries have expectations of what they are going to get from a scrap supplier. And they also might have storage problems that require the scrapyard to carry their inventory. Everything from just-in-time deliveries to the inspection process for scrap has improved, Lasky said.
The specifications on scrap have become tighter, but foundries also are looking at different types of scrap to get the same chemistry. Sadoff & Rudoy shreds plate scrap because its foundry customers like the densities and pieces, but foundries also are looking for different ways to package low-cost material like turnings and borings for reuse.
And scrap suppliers are working with them to develop those resources, said Jason Redden, vice president of marketing at OmniSource Corp. The big Fort Wayne, Ind.-based scrap processor has patented a process in which it makes a block out of borings and turnings. "It's a square block instead of a round briquette. We ship a few thousand tons of those to foundries today, primarily the cupola foundries. It was a product that used to go to the landfill."
Redden said his company is willing to look at material once deemed the dregs of the scrap pile because the supply of prime industrial steel scrap, like No. 1 busheling, is dwindling. That prompt steel scrap comes from automakers and their suppliers, but now some stamping plants are shutting down either because they are no longer needed in an age of smaller cars or they have moved south to fill the needs of the "new domestic" automakers.
"Plus you have SeverCorr (LLC, Columbus, Miss.), a new steel mill in the South that is going to be buying a couple of hundred thousand tons of scrap a month," he said, which will draw even more scrap out of the Midwest. "Some scrap processors don't want to put all that time into making a foundry grade (of busheling). They'll just put it in a rail car and ship it south."
Redden echoed Lasky's comments on foundries' tight chemistry controls. For factory busheling, he said, foundries are very strict on the amount of manganese and whether the scrap is titanium stabilized. OmniSource monitors scrap that comes from stampers and has good relationships with many of its suppliers; if they make any chemistry changes, OmniSource is notified.
Most specialty foundries are looking for scrap with no more than 0.5 percent manganese and 0.05 percent chrome, Thomas Lotz, marketing manager at Morris Iron & Metal Co. Inc., Philadelphia, said. "It's a pretty tight spec. They buy some plate and structural scrap if it meets their criteria. They have a little higher manganese spec for p&s (plate and structural scrap)—0.7 percent," but foundries are hesitant about painted material because of the lead content in girders from older buildings.
In eastern Pennsylvania, he said, there had been three types of basic foundries steel, gray iron and ductile. All of the steel foundries have gone, and now just a handful of gray and ductile iron foundries remain—and they buy much less cut scrap than they did in the past. Most used to buy a 60-40 mix of plate and structurals and busheling, but now it has swung the other way, with anywhere from 20 to 40 percent plate and structural scrap and the rest busheling.
And as in the Midwest, generators of that prompt industrial scrap are disappearing. Through the 1960s and 1970s there was a lot of busheling available from stamping plants in the New England region, Lotz said. Most of those are now gone.