Because no one wants to be the person responsible for the merlot ring on the white linen tablecloth, servers at fine-dining establishments suggest to give the bottle a little twist at the end of the pour to control drips from running down the side. If only it were that easy with steel.
In mills from Gary, Ind., to Calcutta, India, red-hot metal is poured from one vessel to another on a daily basis. And even though a hard-to-remove red wine stain can seem like the end of the world, spilling any amount of molten steel can be catastrophic. It would take a little bit more than cold water and peroxide to clean up that mess.
So to avoid accidents, it’s best to outfit a facility with the most appropriate equipment for the task at hand. For moving liquid metal from place to place, Boltech Inc., Youngstown, Ohio, has a solution. The company’s ladle transfer cars provide ease of mind when it comes to catching and handling hot metal as it’s poured from a furnace.
"There was a time when, instead of using a car, if it was possible, a mill might have had an overhead crane that would hold the ladle while the vessel was tilted over and pouring out," explains Mark Hogan, vice president of sales at Boltech. "But that’s very tough duty on a crane because of all of the smoke and heat that’s rising up. On top of that, you’ve got this poor crane operator who’s trying to see through all of that as he’s holding the ladle."
One would think that 500 tons of steel dangling from a crane is the last thing any business owner would want to be liable for, especially when that steel can measure up to 3,000 degrees Fahrenheit. Keeping a ladle as stationary as possible is a safe bet, and to do so, the largest car that Boltech has approved thus far can support up to 500 tons.
Make it your own
A new trend that’s surfacing for connoisseurs is wine blending. Mixing different parcels together can satisfy some of the most sophisticated pallets that may have become bored with a standard pinot or single beaujolais. And it’s no surprise. Customization is prevalent in all areas of life. What works for one person, might not serve the next.
For Boltech customers, the transfer cars can be specialized to suit a mill’s individual ladles. To produce a ladle transfer car for Nucor Steel Decatur, Boltech worked alongside Clayton H. Landis Co., a firm that provides Nucor with engineering and project management services. "The new ladle car was commissioned in December 2006," says Joel Payne, engineering supervisor at Nucor Steel Decatur. "The car is currently used for transfer only but is designed to accommodate a weight system."
Boltech’s 15 engineers start with one of three different model types and then work off that basic model to incorporate a customer’s needs. A transfer-only car is used strictly to hold a ladle. A transfer and weigh car does just what one would expect: transfer and weigh a ladle. And the transfer and tilt car can pour a ladle 50 degrees or more as necessary. Any of these cars can also serve as a temporary location for testing.
"They can hold a ladle full of molten steel while it’s being processed at a ladle metallurgy station," says Hogan. "This is where they fine-tune the chemistry of the heat and make sure that it has the right temperature before it goes to the caster. There are several melt shops that still use a crane to hold the ladle, but if you’re going to do any type of ladle metallurgy or conditioning before it goes to the caster, you’re almost guaranteed that it’s going to sit on a car."
"Liquid steel is tapped [or poured] out of the electric arc furnace into a ladle which is positioned in the transfer car," Payne says of the custom equipment. "Once the ladle is full the operator will move the car, via a remote control station, to a position where an overhead crane will pick up the ladle."
To produce the ladle transfer cars, Boltech, now a vintage 1997 company, employs 130 people at its 110,000-square-foot manufacturing shop. In addition to its manpower, Boltech relies on its own specialized equipment to get the job done. When it comes to crafting large-scale machinery as in the case of Boltech--some of the company’s cars have measured up to 18 feet wide by 30 feet long--the manufacturing capabilities have to be just as big.
"One of our specialty machines is a Scharmann horizontal boring mill," says Hogan. "It’s probably one of the largest machines on the East Coast. It’s a seven-axis CNC machine. It has a travel of 315 inches on the X-axis, 197 inches on the Y-axis and 102 inches on the Z-axis. It’s hard to imagine a 90-ton machine speeding away like that, but it is a very impressive piece of equipment. It chews off the chips like you wouldn’t believe."
Improving with age
People have been sipping, swirling and spitting since ancient times. Early man was purportedly fermenting grapes more than 7,000 years ago, and in the grand scheme of things, not a lot has changed. Likewise, in the production of transfer vehicles, the standard model hasn’t had to make much of a transformation since its initial introduction to the industry. It has accepted a few tweaks, however.
"The biggest thing that has occurred is the desire for impact protection of the wheel support bearings," says Hogan. "We actually put coil springs above the bearings to protect the axles and wheels from the entire impact. You can imagine if someone is putting a 300-ton ladle onto a car, it tends to wear on it. Now we have springs to absorb the impact load that compress up to 1 inch so that we don’t have that shock loading on the systems of the car. It really helps to improve the longevity of the components."
Some other improvements have been made to increase the durability and lifespan of the Boltech models. "There was a time when the industry was using rubber shock pads, which in most cases have been a disaster because rubber pads are only good until about 160 or 180 degrees," Hogan explains. "After that they melt. You’d be amazed that some people are still using them in hot applications."
Other alterations that ladle transfer cars have underwent also deal with the extreme temperatures that they must endure. Hogan says that the company’s customers have a tendency to destroy equipment on a regular basis because of what they’re trying to process and because of the environment in which they’re doing so. Therefore, Boltech is continually developing parts that can withstand a high amount of wear and tear.
"We’ve been replacing the drive gear boxes on the cars," he says. "They used to all be fabricated steel boxes, but we’ve pretty much switched over to cast-iron gear boxes. The frames are much more thermally stable. What we ran into with fabricated steel boxes was that as they were exposed to the heat that can be underneath these cars, like molten slag, the steel would actually stress-relieve itself and move. We’ve found that that isn’t a problem with the cast-iron boxes; they’re more heat tolerant."
So while a Boltech ladle transfer car can withstand the extreme conditions of a mill environment, perhaps an informed host or hostess can withstand the snobbish scrutiny of a hard-to-please guest. Determining which varietal will best pair with coq au vin and establishing the best manner to handle molten steel are two entirely different tasks. But they do share a common thread. The more knowledge that is applied, the better the end result.MM
By Abbe Miller, from the January 2008 issue of Modern Metals.