August 2012 - In the heart of the United States, 22 heavily loaded semitrucks embarked on their trek westward from Moundridge, Kan., to Vancouver, Wash. Inside each vehicle was a section of the massive piece of equipment needed to help Farwest Steel Corp. open its 330,000-square-foot coil distribution and processing site.
A flat-rolled supplier in the Northwest, Farwest Steel wanted to complement its extensive array of value-added services with a cut-to-length line. “We’ve been a flat-rolled supplier in the Northwest, but until now, our coil has been leveled through third parties and at one time was leveled at the mills,” says John Worstell, vice president of the steel division at Farwest Steel. “We decided we needed to get into leveling internally because our customers wanted us to be more efficient and faster,” he says.
After acquiring a number of regional companies in 2005 and 2006, Farwest Steel decided it needed to consolidate its existing Eugene, Ore., and soon-to-be completed Vancouver shops. After determining a location, Farwest Steel researched leveling capabilities throughout the Northwest and found “there weren’t any stretcher levelers,” Worstell says. “We were concerned about our need to provide a product as good as the Northwest market was used to, as well as the ability to improve upon that standard,” he adds.
“We knew we would have to prove ourselves as our product would get scrutinized very closely,” Worstell says, noting customers would want to know how Farwest Steel’s product would hold up to laser or plasma cutting. As the company evaluated stretcher levelers, it found The Bradbury Co. Inc., Moundridge, Kan., a subsidiary of The Bradbury Group.
Bradbury’s eDrive System uses dual motors that create tension inside the leveler. “This greatly reduces internal stress and has a higher than usual effect on strip shape,” says Brownie Cox, senior sales advisor for flat products. Bradbury now has more than 20 eDrive levelers in the field and more on order.
Meeting a range of needs
Farwest Steel provides products for a variety of industries, including agriculture, marine, transportation and material handling equipment. The company needed its new line to process hot rolled A36, as well as high-strength low-alloy steels—up to 100,000 yield grades of material and eventually even higher.
Farwest Steel installed a line with two levelers using Bradbury’s eDrive technology. “Our line is a twin leveler line, so we have to have the ability to go from 14 gauge to 1⁄2 inch all in one line,” explains Worstell. “Using the eDrive allows us to run different sizes at fast speeds, all through one line.”
Farwest Steel’s line is equipped with electric braking on the dual mandrel uncoiler. “This is important for two reasons,” Cox says. It provides automatic back tension to the eDrive and maintains a steady tension throughout the entire coil.
“This means the material will be processed consistently regardless of changes in coil as it decreases in diameter,” Cox says. The second advantage is most of the time the motors are in a regeneration mode, capturing electrical energy that is fed back to the system and used by other devices in the line.
The combination of electric braking with the eDrive system increases the cut-to-length line’s efficiency. According to Cox, special instrumentation has been installed to monitor power consumption, regeneration and savings that can be accessed and monitored in real time online by Bradbury.
The technology also can be adapted for companies with existing, older leveling technologies that struggle with higher yields and laser flatness issues, “without increasing the present footprint,” or size of the line, Cox says. The eDrive leveler doesn’t require more floor space than the old leveler it replaces. There is no need to move or rearrange a shop’s existing layout, which could result in costly foundation or footing work.
Ongoing research and development allows Bradbury to upgrade older designs to the new eDrive platform, Cox says. “The upgrade provides this new technology at a fraction of the cost of a new leveler,” he adds.
The finished parts Farwest Steel provides must be memory-free. When laser or plasma cutting, warping of material can negatively impact customers’ manufacturing processes. “From laser heads getting damaged to warping or cambering of parts—we can’t have it happen,” Worstell says. “Customers don’t want to have to fix damaged laser heads or have to straighten out parts before they can be machined or welded. Robotics are getting to be a bigger and bigger part of our businesses, and our customers need to have that flat, uncambered material.”
Worstell says the eDrive allows Farwest Steel to produce flatter plate than with conventional roller levelers. Instead of one drive, the eDrive uses two drives, each powered at a slightly different speed, causing a pulling and braking action, or tension, as the material goes through the rollers. That action produces memory-free material.
“Material in its master plate form comes through the leveler and remains flat,” Worstell explains. “As it gets cut into long narrow plates or pieces, the tension induced through the leveling process starts to relieve itself, allowing parts to bow and buckle, returning back to their coil form.
“Instead, the eDrive pulls more of that memory out of the material,” Worstell continues. “It just allows the parts that are cut from the product that have gone through the leveler a better opportunity to remain flat. And the ability for a finished part that is cut from leveled coil to stay flat is absolutely crucial to the manufacturing process.”
Worstell emphasizes the importance of flatness to both Farwest Steel’s operations and its customers who purchase stock sheets or plates from the company. “Everybody is focusing on how to keep their material flat—and that’s flat throughout the entire process,” Worstell says. “From leveled coil through finished part. For a company like us, producing parts as narrow as 10 inches wide and 60 feet long, to parts that are 8 feet wide by 60 feet long, we want to minimize wave and camber in the parts. We don’t want them turning into a banana.”
The leftover scrap skeleton also can warp after cutting small 3-inch to 4-inch square parts. The scrap can buckle and damage cutting equipment, resulting in costly repairs and lost production time.
For long, wider parts, Worstell says the company wants the material to be flat and not have horizontal or vertical waves. “We bought the flat track on the line and feel very confident this line will produce the flatness we need,” he says. “We’ll get to monitor and track the leveler to ensure it’s producing the flatness we expect.” MM
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