June 12, 2003
A growing manufacturing base in the Southeast spurred Thompson Steel in the mid-1990s to research what type of equipment to purchase for its new facility in Fountain Inn, S.C. The steel supplier had been shipping coils of slit steel from its plants in Baltimore; Franklin Park, Ill.; and Rome, Ga., almost daily to several customers in the area.
The decision to produce cut-to-length steel and blanks at the new plant arose from regional stampers' and other manufacturers' need for these products.
Once committed to building a new plant in the Southeast, Thompson's management began planning the facility's production capabilities. Because the company supplies a variety of industries, including stampers that supply BMW, John Deere, and Siemens, it needed equipment that would be versatile and could keep up with a heavy production schedule.
Thompson set out to determine the nature of the plant's likely customer base by conducting a market study of all the region's businesses that were using flat-rolled steel. The company's representatives surveyed not only Thompson customers, but also potential customers, noting the grade and type of steel each business required at that time and their anticipated future needs.
Also contacted were two mill suppliers from which Thompson was buying unprocessed steel. This was done to determine exactly what these companies were shipping into the region and to track any trends. The study concluded that the initial mission of the new plant should be to supply what was found to be a growing demand for blanks and cut-to-length steel.
Next the steel supplier began a comprehensive process to select the production line equipment for the new plant. Four manufacturers of such equipment responded to Thompson's call for bids. Over the next 10 months, Thompson management visited plants where bidders had installed their equipment, comparing design plans, performance, and production values. The company selected at the end of the process was Red Bud Industries, Red Bud, Ill.
Designed, built, and installed by Red Bud Industries, the multiblanking production line at Thompson Steel's South Carolina plant has broadened the company's customer base by providing rapid, customized service to stampers and other fabricators in the Southeast without the cost of long-distance freight.
Overall, according to Jeff Goodreau, plant manager with Thompson Steel, the decision to install a Red Bud multiblanking line at the new plant had to do with productivity, versatility, and reliability of the equipment (see Figure 1). Specific factors considered included the tolerances the company would be able to offer its customers. Because of its proprietary grip-feed measuring system, the supplier was able to ensure the widths of the orders coming off the line to an accuracy of ±0.005 inch.
Maintenance figured into the equation as well. For routine cleaning and minor adjustment, the company found it was easy to access key components in the production line. Also, almost all day-to-day maintenance could be performed by in-house employees.
In January 2001 Thompson opened its new 80,000-square-foot Fountain Inn facility. According to Goodreau, initial delivery estimates have been exceeded, and the production capability of the multiblanking line allows for expanded growth. The line can handle master coils from 15 to 72 in. wide and 28 to 75 in. in diameter and up to 50,000 lbs.
Capable of running 400 feet per minute, the line can produce large quantities of cut-to-length sheets (up to 72 by 192 in.), as well as shorter, narrower pieces called blanks. These blanks are cut to precise lengths and widths, and the line has the ability to turn out blanks as small as 6 by 6 in. (see Figure 2).
The CNC on the multiblanking line helps cut large orders of steel to precise lengths and widths with variations of no more than 0.005 in.
It is not uncommon for the steel supplier to produce cut-to-length sheets or blanks in the morning and deliver them that same afternoon. Just-in-time (JIT) can be an unforgiving phrase. One customer offers only a 45-minute delivery window before the next truck is blocking the loading dock.
In addition to the freight costs saved by having a plant nearby, Goodreau comments, the line offers speed and reliability that allow both Thompson and its customers to operate with smaller inventories and to meet JIT delivery schedules.
Equipped with a CNC slitting head, the multiblanking line simultaneously levels the steel as it passes through the line. This means that as a coil is unwound, it doesn't need to be recoiled between leveling and cutting-to-length. Some raw material coils are more distorted than others, and the line has an adjustable roller/leveler to improve the flatness as necessary. Uniform thickness is not a problem, because the company works with prime metal.
Because steel is cut and sized to order, scrap is minimal. Toll processing, in which the customer supplies the steel, constitutes a major portion of the plant's business.
Today the steel supplier serves about 100 customers annually throughout the Southeast, providing slit steel in thicknesses ranging from 0.015 to 0.250 in. Last year Thompson Steel installed a second Red Bud production line to fill the needs of stampers and other fabricators who buy their steel by the coil.
The new line, with two packed-arbor slitter heads with shimless tooling, handles coils up to 84 in. in diameter and offers a tolerance of ±0.002 in. The slitter heads are run in tandem so that one slits while the other is "being built" offline. Changeover takes less than three minutes.
The slitting line's looping pit is 30 ft. deep, but a loop-doubler system in effect doubles that to almost 60 ft. When the outer loops come close to the bottom of the pit, the operator activates the pinch rolls to engage the strips, stopping the movement of the original loop before it touches the bottom and simultaneously starting another loop, all without slowing down production. A computer helps synchronize the doubler with the strip speed.
To keep camber at a minimum, a contact sensor monitors and measures strip position and controls a motor that moves the slitting head to the side as needed. According to Goodreau, the computer minimizes slippage and monitors the rotating speed of all driven arbors and rolls to keep everything synchronized. If it can't compensate enough, it shuts the line down. Motorized separator bars keep the line's self-nesting slit mults on track. The operator pushes a button to make the bars oscillate to push the strips between the separators.
In spite of the recession, Goodreau reports, the Fountain Inn facility has boosted Thompson Steel's business. Since it began production, the plant has increased the company's overall revenues by approximately 12 percent. The enhanced versatility has broadened the company's product range in the marketplace.
Thompson Steel, 120 Royall St., Canton, MA 02021, 781-828-8800, fax 781-828-5082, www.thompsonsteelco.com.Red Bud Industries, 200 B & E Industrial Drive, Red Bud, IL 62278, 618-282-3801, fax 618-282-6718, www.redbudindustries.com.
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