Even though the automotive industry shapes people’s perception of Usa manufacturing, and metal manufacturing especially, it isn’t the nation’s largest consumer of metal-not from a long shot. It’s commercial construction.
To lessen cost, builders have trusted design techniques to reduce the level of seamless steel pipe a structure needs, in addition to reduce on-site erection time. One design avenue that is far more popular inside the past two decades is to use choices to the conventional wide-flange beam.
These beams have become a reliable building material associated with preference. But in terms of strength, the form from the wide-flange beam pre-sents a challenge. It might span simply a certain distance (or “unbraced length”) before requiring support. Coming from a purely strength perspective, it could be a lot more efficient for beams to take on a circular, square, or rectangular shape, which would extend the most unbraced length. The more time distance these structural members are able to span, the fewer braces and supports a building needs. Ultimately, this implies builders may use a smaller amount of what’s often their biggest expense: the structural metal itself.
Enter hollow structural sections, or HSS (see Figure 1). These round, rectangular, or square tubes have shapes that provide inherently higher strength and will span greater lengths between braces. A square steel tube using a 3/16-in.-thick wall thickness posseses an allowable load of 79 kips spanning a column duration of 32 ft., while a similar wide flange (ASTM designation of W12 x 40) has an allowable load of 64 kips within the same column length (see Figure 2).
For several years HSS happen to be utilized for their dramatic effect. Builders and architects used those to make an artistic statement, not to economize, which remains true on many occasions today. But because HSS are so strong, architects can design buildings with less material. HSS also save money on finishing costs, because in comparison to hollow steel pipe, tubular sections have less area to paint or fireproof. Combine this with the fact that tube production costs have fallen in recent times, and building with HSS starts to make real economic sense. This is one major reason that need for HSS is going up since the recession, and it’s with this environment the tube cutting laser is commencing to start new opportunities.
HSS represent a departure from many tube laser cutting applications that tend to use relatively thin-walled workpieces. Shops providing HSS often must deal with workpiece weights (called “stick weights”) approximately 2,000 pounds. These workpieces are not only long, but in addition large; 14-, 16-, and 20-in. diagonal cross sections aren’t uncommon.
To create such large workpieces cost-effectively over a tube laser calls for careful planning. It’s far more complicated than by using a cutoff saw, but it additionally adds considerably more value to the workpiece. Modern tube lasers have load/unload functions that could handle mill-length pipe and structural material.
This capability gives designers stainless steel seamless tube in terms of designing for mated sections. Mating a round tube to another one round tube seems simple, but the bevel required dexopky12 build a tight fit-up in between the two sections can be quite complicated, especially if tubes are of several diameters or shapes, or maybe if they intersect at unusual angles.
From an architectural engineering perspective, such angles may make the best transfer of loads and the majority of efficient consumption of HSS. But on the welder and fabricator, this type of complicated joint can be quite a nightmare.