Automation's Advance

Dec. 21, 2004
Manufacturers in a variety of industries are moving toward the fully automated plant, but the human touch remains.

Judging from the state of the art in high tech, textiles, and even some traditional manufacturing industries, the notion of the lights-out factory remains an elusive goal. Even so, many companies in these and other industries are making major strides toward the fully automated plant. Manufacturers such as ABB Inc., HMT Technology Corp., and Unifi Inc. are implementing new automation to their manufacturing processes almost daily in an effort to reduce costs, eliminate human error, and shorten the time it takes to make products. A look at just a few plants that are leaders in their industries in applying automation reveals that although some processes can be streamlined with technology, there remain many manufacturing operations that still require people to perform key tasks. ABB moves toward seamless operation An international manufacturer, one of whose many businesses is automation systems, ABB has embarked on an ambitious global plan for its power transformer unit to create a seamless, fully automated, integrated manufacturing system. Ultimately, the system may be used in many of the company's 32 transformer plants in 25 countries. "We are expanding other plants in the U.S. and Europe using this concept," says Zurich, Switzerland-based Steven M. Hegyi, manager, operations, ABB Distribution Transformers. The showcase of the plan is ABB's TXF-21, or Transformer Factory of the 21st century, located in Athens, Ga. Touring the plant, a visitor notices conveyors and robots performing key tasks, but workers still are a necessary element of production. On one production line, a series of robots manages an entire cell that fabricates the metal box, or tank, that will become a pad-mounted transformer, used primarily for new residential construction. The combined production at the Athens plant and at one similar to it in Jefferson City, Mo., makes ABB the largest manufacturer of power distribution transformers in North America. As the manufacturing process begins, robots pick heavy-gauge sheet steel, using lasers to cut holes for connections. The metal is bent into sections to form the sides and bottom, and the sections are welded together to form the tank. One robot holds the sections, while the other does the welding. The seam welds are important, because later the tank will be filled with oil to absorb heat and insulate the copper-wound transformer core. This entire process is done by a team of robots working inside an area fenced off to humans for safety purposes. The feeling one gets is a little like watching exotic animals in the zoo. At the next workstation a robot proceeds to mount 15 threaded studs where other parts or attachments will be secured. The welding of the studs was a particularly challenging automation problem. Typically this would be a job for a worker, since the weld must have strength characteristics that require the use of a ceramic ferrule at the base of the stud to protect the metal from being weakened by the intense heat of the welder. But ABB automation experts figured a way to have a robot, working with great precision, execute the weld without using the ferrule, saving more than a dollar's worth of ceramic parts per unit. When making 800 transformers a day, seven days a week, the savings can add up. "We've invented a lot of technology to run this plant," says Tarak Mehta, an engineer at the Electric Systems Technology Institute, part of ABB's automation R&D unit. "This system is at the cutting edge of what technology can do today." ABB, in fact, is still working the kinks out of some of the new robotics. During a recent production run, the robot doing the stud welding dropped two studs in a row and then stopped, thereby freezing its brethren up the line in their automatic tracks. With the aid of the system's built-in diagnostics, a technician immediately swung into action and fixed the problem. The machines were up and running again in a few minutes. "It's painfully obvious when there is a problem or error," comments Mehta. "It stops by design -- the system can't make a bad part." Similarly, there is no chance that a mountain of tanks could be built with a problem, such as a bad weld or leaky seam, because the system automatically shuts down when a problem arises. On a different line, one that builds pole-mounted transformers, a team of robots was busy fabricating cylindrical tanks. These devices will be sold to utilities as replacement units in existing residential neighborhoods. The act of welding the seam along the inside of the tank is particularly tricky and potentially dangerous if done by humans, who, after umpteen hours straining to reach inside the tank with an arc welder, could make a mistake, missing part of the seam or injuring themselves. The use of standard components is important to ABB's "flexible automation" concept. "We take a very large list of standardized components to create a very customized product for the customer," says Herb Grant, power transformer division marketing manager. But ABB didn't achieve this level of automation by chance. The company was seeking a strategic plan that would ensure the competitiveness of the division well into the 21st century. One reason for the effort: ABB management could see that other transformer makers with lower labor costs were looking to grab a larger share of the North American market, where ABB is the leader. "We were being challenged to do something different, so we knew this would be a high-risk project," says Hegyi. "We're not going to get ahead of our competitors if we just do it the way everybody else does." ABB looked at its product technology, manufacturing automation, and business systems. The company found ways to improve all three, but the most dramatic gains came through accelerating the order process and using in-plant automation to speed production and order-to-delivery times. As a result, ABB's labor and overhead costs for the facility are down by one-third, while total costs are 20% lower. The most impressive gain was in throughput time, which has been cut by 90%. Despite all the automation at the ABB facility, though, hundreds of people still work in the unionized plant -- they just do different jobs. Some are materials handlers, moving units from here to there. Some perform tasks such as mounting transformer cores on machines that wind them with copper wire. Operators and technicians check robotic systems, perform maintenance, and tend to breakdowns. For instance, one manual task has workers lifting the transformer cores and setting them inside the tanks. They rotate each core slightly so that it clears obstructions and fits inside. "In this application, the core won't go straight in," explains Mehta. "And because the human eye is so much better than a robot's, we have people put the core into the tank." HMT Technology strives for perfect products Although engineer Jack Kelly will tell you that a human never touches the product at HMT Technology's Fremont, Calif., plant that makes hard-disk drives, it's also true that there are plenty of people working at various steps in the manufacturing process. Some shuttle stacks of drives from workstation to workstation, while others work in specific areas that have yet to be automated, such as packaging. And, of course, there are plenty of people, like Kelly, whose role is to maintain and upgrade the equipment. HMT makes metal platters that later will be assembled by its customers into hard-disk-drive assemblies for desktop and laptop personal computers. The circular aluminum disks measure about three and a half inches in diameter and have a mirror surface. Because of the nature of the product, human involvement in the manufacturing process is to be avoided whenever possible. Much of the work area inside the firm's 250,000-sq-ft, state-of-the-art plant is a clean room. In this area, workers must wear white gowns, booties, gloves, hats, and masks. The reason is that a piece of dust, a stray human hair, or a tiny piece of skin could render a platter inoperative. "We're always looking to use more automation," explains David Gruebele, HMT's director of sales and marketing. "The fewer people in the factory, the better chance we have of making a perfect product." Apart from the clean aspect of the manufacturing environment, HMT also has sought to reduce human involvement as a way to eliminate errors. "You're asking a human being to make the same type of movement thousands of times a day and not make a mistake," says Gruebele. Even so, product quality wasn't the only reason HMT looked to accelerate its use of automation. Labor cost was another. Most disk drive manufacturers are located in the Far East where labor is cheaper than in the U.S., and management decided that that a move toward full automation was critical for the company to survive and prosper. To that end, in 1997 HMT built a $380 million state-of-the-art manufacturing facility next to its existing site in Fremont, southeast of San Francisco and very near Silicon Valley, although most of its customers are in Asia. Workers can be found throughout the plant, yet most of the key processes are done by machines. These include chamfering, turning, grinding, plating, annealing, polishing, and washing. Once these tasks are completed, the disks are sent via conveyor to machines that put tiny grooves into their surfaces. Riding on an underwater conveyor, the disks are scrubbed clean of the diamond-based slurry used in the grooving process. Next, a laser is used to burn a texture into the surface. Later, a sputtering process coats the disks with 17 layers of thin magnetic film. A couple of molecules of lubricant are added to the surface to prevent wear from friction. The disks then are buffed before moving on to a testing workstation where each unit is examined for data integrity "so the customer has no risk of losing data," Gruebele says. The entire manufacturing process encompasses several physical sciences, including chemistry, physics, and electrical engineering. "It's the highest-technology device in the PC," says Gruebele. Throughout the largely automated production line, the disks travel in bar-coded cassettes, plastic racks containing 25 each, with each batch radio-frequency tagged. The bar code identifies the cassette; the RF tags track its location and movement. Each batch is tracked by a manufacturing execution system (MES) from Camstar Systems Inc., Campbell, Calif. "Camstar keeps track of everything happening in this factory," Kelly says. HMT figures the ultra-advanced, heavily automated plant won't require significant upgrading or retooling until 2004-05. "We have a staff of engineers who are continually improving the equipment," says Kelly, a member of the team that built much of the automation the plant uses. "We're always looking for new, higher-tech machines to do the job better." Kelly explains that the plant was designed so that a malfunctioning robot or series of machines causing problems in one area wouldn't shut the entire operation down. "We didn't want a Denver airport type of glitch," he says, referring to the infamous debacle several years ago at the new Denver International Airport where a baggage conveyor system suffered a near meltdown in front of the press. HMT engineers designed the building to contain four smaller manufacturing bays, each with its own power, water, and other resources. Each bay can make the product independently of the others. The facility ships an estimated 120,000 disks daily. "We can shut one line down at a time if needed," he says. HMT engineers created the automation systems, the orientation of the line, as well as all the networks that link the various operations. "The most difficult part of all the automation is the software and the integration," Kelly says. In some cases, automation equipment on the line has a built-in trapdoor that enables technicians to work on it from outside the clean-room area, thereby reducing the possibility of human contamination of the product. Although final product packaging currently is done manually, HMT is looking for a machine that will automate this step, as well. Unifi realizes ROI One of the leading producers of polyester yarn for textile manufacturing, Unifi has about 80 employees at its highly automated Yadkinville, N.C., plant. Most workers are supervisors who work in the control room, or operators who handle maintenance and repairs. Responding to pressure from customers to move to a build-to-order model with smaller lot sizes, Unifi installed automation equipment to enable it to perform automatic machine setup on the fly. The company also was successful in creating a fully integrated production system, linking an MES from Camstar with an Oracle Corp. enterprise-resource-planning system. Orders come in from customers via fax or EDI, generating a work order, and then the MES system begins to manage production. Materials are moved throughout the plant by automated guided vehicles that pull yarn packages off winding machines as each step in the process is completed. "The combination of the MES and automatic material handling took a lot of the direct labor costs out, for a reduction of about 65%, " says Rob Rudder, marketing director at Unifi Technology Group, a spinoff that provides consulting and systems-integration services to other manufacturers. "We were so successful with this technology that we figured we could get a better return spinning out our technology group to offer this knowledge to other manufacturers." An important benefit of the MES is the ability to track production history in case there is a problem. "You know exactly the path the product took through the manufacturing process," Rudder says. "This has led to significant quality improvements." Other gains achieved at the Yadkinville facility include a reduction in cycle time to two hours from a day and a half. "The whole system is dynamic, so the plant can react quickly to orders that come in," Rudder adds. That flexibility, of being able to handle smaller lot sizes,drives to the bottom line, he says. "You create new markets you thought you couldn't go after." He estimates the company's return on its automation and systems spending at more than $10 million over the cost of the project.

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