By RICHARD MANDEL, senior editor

At a 6-employee shop in Colorado, a Lincoln Electric eCell welds a bracket for agricultural equipment.

One of the best ways to gauge overall acceptance of a technology is to observe its presence in the marketplace. For example, the first combination watch-calculators, made by Hewlett-Packard, sold for nearly $900 to those who could afford the novelty. Within five years, anyone with $20 had the ability to sport one on his or her wrist. A more recent example is the cell phones with cameras, music storage and other extras that are popular with the 12- to 16-year-old set. Just a few years ago, cell phones were an elite novelty themselves, and only were used as mobile telephones.

Today, sophisticated welding robots that were the leading automation items for a privileged few welding shops can be purchased at the catch-all bazaar, eBay, alongside antique pottery, collectible watches and special-edition Barbie dolls.

So, if welding robots are readily available, why isn't one in your shop?

Robot as employee
The welding robot, once seen only in large-scale operations such as auto production lines and oilfield pipeline shops, has been finding employment in successively smaller shops. Improvements in motors and motor controllers have led to smaller robotic equipment; while control interfaces have been simplified to reduce an operator's learning time. Concurrently, the prices for complex robots have fallen, and cost and sophistication is less of a barrier to adding automation today than it was as recently as a decade ago. Or, as Tom Smith, vice president of industrial robots integrator RobotWorx (www.robots.com), puts it, welding robots are now "just another tool in the arsenal - it's not voodoo anymore, it's a dependable, proven tool."

In a promotional brochure for Lincoln Electric's (www.lincolnelectric.com) automation division, it's suggested that, "In a perfect world, your labor costs would be predictable, steady and reasonable; increasingly intense competition wouldn't be squeezing your profit margins; the available pool of skilled welders would be vast; (and) your customers wouldn't be demanding higher quality, shorter turn-around times, and the use of tougher-to-deal-with materials." To which Geoff Lipnevicius, engineering manager at Lincoln Electric, adds: "Any decision making for a robot system typically involves the shop owner looking at financial factors — what is the payback, and what's the return on investment. There are additional factors that sometimes override the financial aspects, such as improvements in quality, skilled labor shortages."

Once programmed, the robot can produce consistent results, as long as the components presented to it are consistent in form and fixturing, and the equipment itself is regularly maintained. The machine can operate without regard to a time clock, and reports to work at the flip of a switch.

Moreover, automating the welding process provides a buffer against the diminishing pool of skilled welders. In an article printed August 15, 2006, the Wall Street Journal said: "Welding, a dirty and dangerous job, has fallen out of favor over the past two decades, as young skilled laborers pursue cleaner, safer and less physically demanding work. Now, thanks to a global boom in industrial manufacturing, skilled workers are in greater demand than ever. Companies can't find enough of them." Until more welders become available, robots can handle repetitive production-line tasks that do not entail great variation between parts.

While buying a robot is less expensive in the long run — as opposed to hiring an employee who requires a paycheck, training, health benefits and time off — skilled welders certainly are not totally replaceable. Many jobs still require on-the-spot decisions, such as when a misalignment occurs between the parts being worked. Not all jobs can be fit into an automated weld cell, either, so they require welding personnel working away from shop floors, such as bridge repairs, many other outdoor jobs and non-OEM tasks.

There's also a need for someone to set up the robot. "The best people running welding robots are good welders," says Smith, adding, "A good welder who can program, can then program five welding robots. How valuable is that to a company?" As one engineer from Miller Electric (www.millerwelds.com) recently remarked, "I can train a welder to program a robot easier than I can train a programmer to weld".

Competing
A consortium called Save Your Factory (www.saveyourfactory.com), formed a few years from several manufacturing companies, associations, and publications (including our sister magazine American Machinist), urges North American manufacturing companies to recognize automation, robotics, and efficiency measures such as lean manufacturing, as more cost-effective and profitable alternatives to off-shore manufacturing. In a white paper titled "Manufacturing Competitiveness through Robotics and Automation," issued by the consortium in December 2005, the author says "There are numerous factors to consider when moving manufacturing operations overseas.... Producing products in other countries such as China also provide challenges in maintaining high quality parts. Counterfeiting costs the global automotive parts industry $12 billion a year; $3 billion of that total is in the United States. In addition, according to the U.S. Embassy in Beijing, companies investing in the Chinese market underestimate the market situation, failing to perform risk assessments and seek council.... All data supports the fact that through automation, robotics and other lean manufacturing operations, North America can be cost competitive with countries like China."

As manufacturing decentralized into smaller and smaller job shops, the need for high product volumes strained the small shop's abilities. Even after one robot is installed to handle a major contract, many shops have found that the weld cell is kept busy only three days out of seven. Software improvements that have made programming a robot more "user-friendly" have helped shop managers to learn how to program many different part setups into the memory, speeding changes between jobs and occupying the robot full time, even as much as to two shifts.

Thus, the small job shop not only can meet quotas and compete, but can increase business and grow as well. "A guy who bought a robot through us for a specific job will call six months later, ready to buy a second robot because he's been able to take on more business, often because he could increase the jobs handled by the first robot," Smith says.

When not a robot
The practicality of investment in automation is not necessarily due to high production volumes a robot can provide, however. Lipnevicius cites installations with heavy earthmoving equipment manufacturers, such as Caterpillar Inc. and John Deere Co., where the robot runs non-stop for 9 to 10 hours on a single part such as a cab assembly or a shovel. There are also cases in pipe welding in which a robot may weld a few pieces of 6-in. water pipe, then a few pieces of 2-in. steam line. Despite a non-production-line flow, the robot lends accuracy and speed, especially because it can maneuver non-stop around a piece of pipe — in some cases reducing weld time from 30 minutes to 9 minutes.

However, there are times where a robot is not appropriate for a shop. Says Lipnevicius, "We've turned down jobs. Most of the time, the jobs relate to repeatability of the parts. The robot can be programmed to be very adaptive to changing conditions, but if those conditions go outside the envelope of what the robot can accommodate, then you're going to have a condition where you'll be making scrap very productively."

Additionally, there are shops that have a lot of welding and still not have practical use for a robot. One example is a Canadian company that makes large industrial equipment with heavy steel cabinets, augers and other components. The company considered installing a welding robot in their US repair and spare parts facility, but found that manual welding was more practical for them because every job was different. That repair facility does use an automated plasma cutting table, however, because most of its parts are simple, two-dimensional shapes.

Ultimately, automating the small weld shop has become easier, owing to a wide array of systems from which to select. Many reliable used robots are also available, especially since most auto manufacturers choose to replace their robots when retooling their production lines. More and more shops also are buying rather than leasing robots, an indication that shop owners are buying for the long-term. "Small shops are very smart," says Smith, "They watch their profits, they watch their cashflow, and they know what they can bring to a project."

Family-owned shop not too small for robotic welding Groff AG, a manufacturer of agricultural equipment, was started in the late 1970s by a Nebraska farmer with an idea that led to a better way to fertilize his crops. The company added another farm implement to its production line, and was purchased in early 2006 by another farmer, Allan Winick, who moved it to his 2,000 acres in Wellington, Colo. Winick found himself the only trained welder on his staff, and was putting in 10- to 12-hour days, manually MIG welding brackets, seams and discs. He sometimes worked two-and-a-half days welding 70 brackets. "We only have six employees, and I was spending too much of my time welding. While we were able to fill the orders coming in, the business wasn't growing at a pace I was satisfied with," Winick says. He chose to add a compact robotic cell that was particularly suited for smaller fabrication shops — Lincoln Electric's eCell, with a Lincoln PowerWave 355M welding power source. The 70 fertilizer brackets now are completed in less than five hours. "With the robot, my downtime is minimized due to the flexibility its repeatable programming gives me," Winick said. "Automation offers a shop my size tremendous advantages — more than I realized when I first decided to buy a robot. After the initial setup, testing and programming, all I have to do now is set it and let it do its job." Component parts are manufactured from a high carbon plate steel that range in thickness from 1 /4 in. to 3 /8 in. Discs, which remove debris and break up clods of dirt for a variety of soil conditions, are cut into shapes by a plasma cutter. The pieces are then pulse MIG welded with .045-in. diameter wire and a 90 percent argon/10 percent CO2 shielding gas. With the welding cell, Winick has been able to move from MIG spray welding, where post-weld spatter cleanup was an issue, to modified pulsed MIG welding that requires virtually no cleanup. He added that, before installing the robot, there could be considerable downtime when he moved from one weld to another, or from one product to another. "Our finished products have to stand up to a variety of conditions, including heavy, rocky soil, so the quality and integrity of its construction and welds are imperative. Our reputation is on the line," Winick said. Since he added the robot, the company is working on expanding its dealer network from 9 to 15 states — with an eye toward adding more states down the road. Winick has started to consider other applications for his company's robot, and is talking with a couple of manufacturers about outsourcing some of their welding jobs to Groff Ag. "We've been able to accommodate our regular demand while growing our capacity for other orders and applications. I would have had to hire at least three full-time welders to accomplish what I got with one eCell," Winick added. "The robot has also allowed us to steadily build up our inventory, which we weren't always able to do before. We're now better equipped to meet the demands and expectations of our distributors and customers and have set the stage to continue to grow Groff Ag's business."

Small fab shop meeting rigorous automotive quality and productivity standards A seat bracket welded in Res Manufacturing's robot cell. Milwaukee-based Res Manufacturing Company primarily produces metal stampings, with secondary operations that include heat-treating, shot blasting, deburring and welding for diverse industries such as automotive, cookware and lawn and garden. Prime automotive customers are Tier I and Tier II suppliers that supply components such as engine baffles, interior seating parts, and brackets to Toyota Motor Corp., Ford Motor Co., Honda Motor Company, General Motors Corp., Daimler-Chrysler, Jaguar, Nissan Motor Co. LTD. and Mazda Motor Corp. Res Manufacturing operates in a 90,000-square-foot facility and employs 80 people. Dave Johnson, project engineer at Res Manufacturing, notes that the profit motive contributes to pressures to achieve high-level productivity and product quality. "Since we have endless demand for greater productivity, tools to increase efficiency and quality are mandatory," he says. A 14-year engineering and production veteran, Johnson elaborates on the pressures that face a small company in the automotive fabricating market. He cites as a case-in-point a contract that the company won to produce automotive seating components that required MIG welding. With no prior production-level MIG experience, Res Manufacturing was challenged to achieve quality and productivity. "We knew how to handle the forming, but were now faced with measurable welding requirements," said Johnson. After researching options, the company installed a PerformArc model 102S robotic welding cell from Panasonic Factory Solutions Co. The decision was based on a recommendation from the gases and welding equipment supplier, whose previous experience with this work cell indicated rapid and successful implementation of robotic welding, A fast learning curve for launching commercial production and operators' comfort level were also key factors. Sorenson Industrial Systems, Inc., based in Waukesha, Wis., was brought in to help integrate fixturing for the weld cell. "When integrating products from multiple sources into a single system, it is more difficult, slower, and usually involves performance compromises. Once we received the CAD drawings of the two initial parts involved, we were able to design tooling within three weeks that satisfied specs and were tailored to the specific robot cell," said President Gregg Sorenson." "Utilizing our 3-D models and Panasonic's 3D simulation package design software," continued Sorenson, "we could rapidly and accurately verify issues of the robot's motion, such as reach in multiple directions and access to weld areas. Everything was done off-site so that the customer's manufacturing and engineering associates were not tasked with these efforts." Johnson notes that Res Manufacturing's prime concern was programming: "The robot's teach pendant, using a Windows CE-based interface, offered our operators a familiar and easy means of programming. In fact, as the welding procedures were being developed, some of our people were learning how to program. No time was lost by carrying out both steps in parallel." The work cell, he added, was up and running quality parts only a few hours after installation, programming, and initial test welding. In addition, Sorenson and Johnson collaborated to develop a proprietary design and manufacturing procedure that eliminated post-weld shrinkage.