A reality but still in the early stages of adoption, is adding robotics to the structural fabrication shop. Robotic welding and thermal cutting are not new to structural fabricators, but automated welding is—that is, welding with no manual intervention whatsoever. This includes program development and moving material in and out of rotating fixtures.
Two technology advancements make fully automated robotic welding possible. First, weld programming in these systems now can be automated. Traditionally, robotic welding systems still require programming, so a structural fabricator usually takes a welder and makes him a programmer. But the goal is to reduce overhead and increase efficiency, not increase the labor burden.
Second, robots use sensors and probes (including the use of the welding wire tip as a touch probe) to measure and adapt to workpiece variation. For instance, intelligent systems now can probe toed-in or -out flanges, off-center webs, and whether material is within mill tolerances.
Intelligent welding systems can import data from CAD, if the welding information is in the model. If it is not, a database can recommend the welding information to add to the model; a programmer then can take this recommendation or add in the welding information separately.
At the end of the beam line, beams are automatically loaded into the welding system. From here the detail (that is, the part to be welded onto the beam) is transported, deburred, scanned, and positioned correctly so that the material handling robot can place the part on the beam. Using the wire tip as a touch probe, the welding robot detects the beam’s true position, and then tacks the part. Finally, when all the parts are tacked in position, the robot arm welds the pieces.