When designing a building, engineers perform a lot of give-and-take when it comes to costs. They could select a thinner wall thickness for HSS, saving on material, then again take care of the added cost of additional through-plates or some other connectors so that the structure has sufficient strength. Or they might choose thicker-walled HSS to make certain connections between structural members meet requirements. Architectural engineers may call for connections between HSS, or connect HSS to wide-flange beams. It’s a continual balancing act.
This balancing act may be easier-and here is where hollow section steel tube really can shine. The device effectively makes complex geometries at HSS end sections inexpensive to fabricate. Six-axis laser cutting heads create complex bevels along with tab-and-slot arrangements to simplify fit-up. This includes tilting back and forth (moving along the A/B axis), that may be extremely beneficial not simply for HSS, but for cutting various structural geometries, including wide-flange beams. By tilting, the head can cut geometries in corners, eliminating secondary operations.
This tilting allows for cutting angles for bevels along with precise fit-up between two HSS of numerous diameters. What if you want one tube to slip in with an angle with another tube? A 3-D cutting head can cut the required angles to make sure complete surface contact; that is, no gap between the two workpieces. Systems likewise have secondary tapping units to tap holes inside the laser cutting work envelope (see Figures 3-7).
This done-in-one concept reduces handling and total production time, no less than that’s the optimal. But this is much more complicated than a tube cutoff operation having a saw, and quite distinctive from typical light-gauge laser cutting; again, stick weight might be thousands of pounds. This makes proper planning and inspection much more important.
It starts off with the 3-D CAD model, which from the architectural world is usually incorporated into BIM, or building information modeling. The architectural industry also transfers data via files formatted as Industry Foundation Classes (IFC), a physical object-based building model format created by the International Alliance for Interoperability (IAI). Such files now can be imported right into machine tool software.
The program shows the way the laser cutting machine will process the hollow steel pipe, simulating the complete work cycle. This includes the loading automation, when several V arms position a brand new component of material, whether it be round, rectangular, or square. The simulation then shows the master chuck grabbing into the material and pushing it through another chuck (the slave chuck) and into the laser work envelope.
As being the material moves into position, the software reveals specifically where the probe will contact the workpiece. Touch sensing might be critical with heavy HSS. The probe compares the actual workpiece geometry on the one programmed in the machine. For example, the longitudinal weld in a tube production process can create distortion in extremely long HSS, as well as the touch probe can take into account that distortion.
The program simulates the laser cutting and (if needed) tapping work cycle, ensuring you will find no interferences between your processing heads and workpiece. It simulates chuck movement through the cycle and then shows how the machine will unload the finished workpiece and remnant.
This all is planned before anything moves to the shop floor. This sort of simulation can benefit various fabrication processes, naturally, but it really becomes even more important facing large sections. Moving and fabricating bad components coming from a 2,000-lb. tube represents a great deal of wasted time and cash.
If you think about how long wide-flange beams happen to be used, HSS are still newcomers, however more builders are calling to them. Examine various building designs today, and you’ll see HSS increasingly prevalent, either dominant within a building’s design or providing efficient support between wide-flange beams.
On the fabrication side, most beams being shipped to construction sites are processed through beam lines, and some of the latest technologies in that arena include aspects of the done-in-one concept: seamless steel pipe, tapping, drilling, and much more, in one machine. This idea has carried up to the laser cutting arena, in dexopky12 both the workpiece and multiaxis cutting heads move around in concert to make extremely complex geometries, many regarded as expensive or simply just impossible a little while ago.
The laser made these possible and cost-effective, because process simulation, touch probing, as well as the done-in-one concept reduce overall fabrication time. As soon as these heavy sections get to the work site, erectors can assemble them quickly, shortening overall construction time-which, in the scheme of things, offers the most dramatic result on construction costs. It has been core to the achievements many architectural and structural fabricators recently: Do more within the controllable environment from the fabrication shop to produce things easier from the relatively uncontrollable environment from the construction site.