by Mathieu Bélanger-Barrette
The myths and the reality of robotic welding automation
Even with huge improvements in the last few years, most people think welding automation is still more akin to rocket science. Automated welding systems are getting easier to use and their price is dropping. During the 90s, the number of new arc welding robots in North America grew at an average annual rate of 12 per cent. As we entered into the 2000’s, this rate accelerated to 32 per cent. This means the application is suitable for big industrial plants, and also for smaller workshops that are using robots to get the job done. Have a look at the different myths and realities that are often brought up when considering welding automation.
MYTH: “Only highly repetitive productions justify installing a robotic welding robot.”
With the impressive number of programs that can be stored in a robot controller’s memory, it is easy to go from one part to another. Furthermore, startup times tend to be reduced with new programming techniques. This means that the welding robot no longer needs to be dedicated to one single part or process.
MYTH: “The robot operator must be highly trained and a skilled employee.”
Becoming an experienced welder takes years of training and practice. However, becoming a highly skilled welding robot operator takes less time. By having good loading techniques, a developed sense for quality and minimum programming knowledge, this job is accessible to people on a larger scale.
MYTH: “Robotic welding cells are expensive and difficult to justify cost wise.”
With the rise in popularity of welding robots, the price has dropped dramatically in the past ten years. Today, robots and software are getting faster, easier to use and more accurate. The overall performance of a robotic welding cell has improved and its price has been reduced. So it is now easier to justify the acquisition of this kind of working cell.
What about quality?
Most of the quality verifications are still done by the robot operator. Furthermore, the decision to adjust the robot, accept or reject the part and even change the programming method remains the decision of the operator. With the introduction of high quality robotic vision, the parts can now be scanned and the robot will adjust itself for the next part, in order to have perfectly welded parts every time.
What to remember
While you are analyzing your robotic process, make sure to review the following items: the parts to be welded, weld joint accessibility, repeatability of the parts, tooling nest (or fixturing) requirements, ways to compensate for distortion, and determination of the welding process to be used. Keep in mind that the robot cell layout must consider not only providing space for the work motion device, power source, robot controller and wire feed package, but also how the part is delivered to the area, and how the finished part leaves the area. Workflow simplicity characterizes a good cell layout. Hopefully this article is able to answer a couple of your questions concerning robotic welding automation or inspires you to look further into this process. SMT
Mathieu Bélanger-Barrette is automation junior engineer with Robotiq, St. Nicolas, QC.