Dispelling the Myths
- February 20, 2002
By Mary Scianna
There is probably no better time than now to automate your welding shop. With the average welder approaching his late 50s, and the competitive environment in which businesses operate, automation is the most cost-effective and efficient way to improve productivity.
More importantly, recent developments are making automation a viable option for smaller shops, says Christopher A. Bailey, general manager-automation division for Lincoln Electric Co., Cleveland, OH.
“New options in welding automation are broadening its application and its economic value as a production tool. More flexible programming and finely tuned digital communications between welding power sources, robotics arms and positioning equipment makes it possible to create a system that is economically justifiable and productive for manufacturing operations of almost any size,” he notes in an online article on the company’s web site “Automated Welding…Not Just for the Big Jobs.”
Many companies are now looking more closely at increasing quality and making it easier for welders to do their jobs and one consideration is automation, says Jamie Scripnick, product manager for ESAB Automation North America, Mississauga, ON.
“I see more customers saying we need to be able to improve our process. They’ve being doing the same thing for 20 years and they recognize they need to change to become more competitive and you do that by automating. Some of our smaller customers build components for larger companies and these large companies in turn are looking for less expensive vendors. So automating is a good way for small companies that supply these larger manufacturers to do things faster, more efficient and more cost effectively.”
There is more flexibility in today’s automated system, even with robotic welding, a focus for Brian Doyle, sales manager for Miller Welding Automation. There are different levels of automation and what a welding shop needs depends on its production strategy.
“People use robotic welding because there is a typical productivity gain of 3:1. If a manual welder can make 100 parts in a shift and you take the torch out of his hand and automate this, the same operator can now make 300 parts per shift, but the question you need to ask is 'do you have enough work for this?'”
In a high production environment, a robot with an indexing table and an operator on one side removing the finished parts is one style of automation, but for job shops that typically run high mix/low volume production “a robot in between the head and tailstock—two stations 180° apart from each other—is a better style for making different parts in a high mix and low volume production environment,” explains Doyle.
One of the biggest misconceptions is that automation is simply for high volume production environments, but the combination of new and existing technologies means automation is more accessible to small and medium sized shops, says Louis Dicarie, vice president of marketing for AGT, Trois-Rivieres, QC, an authorized integrator of Fanuc robotics and Lincoln Electric robotic welding systems.
“If you think automation is not for you because suppliers have told you this based on your volume, this may not be the case. Of course you need some overall volume, but because of how we combine 3D vision, robotics and software, a robotic welding cell can adapt to a variety of shapes of different quantities, even lots of one.”
Dicaire says what makes automation more accessible to shops with lower volume/higher mix runs is the automation package AGT has developed, the “Self-Learning Production Cell.” At the foundation, these cells are comprised of one or many six axis industrial robots, 3D laser scanners, welding sources and a set of software tools. The cell automatically loads, scans, inspects, validates, compensates for local deformation from the nominal model, and optimizes the welding process after validation. Once parts are validated, the system knows the robot can perform all the welding paths as the system has compensated and “learned” the new part and so the welding process then starts.
The most significant benefit from today’s automated welding systems is simply that fact that such systems are smarter. Digital communication systems are faster than previous analog versions and the ability to connect between components and to the Internet allows welding operators to better monitor welding processes, not just on the floor but remotely too.
“By bring together the right combination of equipment, software and communications technologies, manufacturers are now able to create technologically advanced arc welding platforms,” says Lincoln Electric Co.’s Christopher Bailer, “that provide seamless integration and high speed communication between welding equipment, PLCs, networked computers and everything from the shop floor to the office computer.”
On the robotic end, Miller Welding Automation’s Brian Doyle says robots eliminate variation and “have the ability to adjust the tip-to-work distance and keep that constant over the length of a seam, and they can better control the torch angle to minimize variability. Today’s robots eliminate the guesswork because a robot operator doesn’t have to pick a torch angle that looks right. Instead, the robot’s teach screen displays the right information, making it easier to use robotic automated welding cells.”
Process improvements are also making welding systems smarter, says Jamie Scripnick, product manager for ESAB Automation North America.
“There are more changes in processes. For instance in the power supply and how we delivery the power to the welding head. We can use the power source and manipulate the wave form to adjust for weld profiles to suit different applications.”
Scripnick is referring to ESAB’s Aristo 1000 AC/DC which features an “on-the-fly” switching function that allows the operator to switch to an AC arc without stopping the process when welding on round objects. The feature helps minimize downtime and the risk of weld defects as the stop and re-start sequence is eliminated.
A good example of smarter automated welding systems is AGT’s “Self-Learning Production Cell” which uses a combination of software and hardware—robotics, 3D laser scanners and cameras—that offers a complete start-to-finish welding solution. The cell automatically loads, scans, inspects, validates, compensates for local deformation from the nominal model, and optimizes the welding process after validation. Once parts are validated, the system knows the robot can perform all the welding paths as the system has compensated and “learned” the new part and so the welding process then starts.