Stainless Steel Expanded Metal
Stainless steel alloys are naturally resistant to corrosion. Composed of at least 10% chromium, stainless steel
expanded metal products develop a thin layer of chromium oxide that resists rust and is self-repairing when scratched. This protective layer renders
expanded metal screens and
meshes impervious to the effects of weather, making stainless steel expanded metal particularly well suited to outdoor applications such as bridges, walkways, fencing and utility enclosures. Also self-sanitizing, expanded stainless steel is common in food, chemical and medical industries where a hygienic metal is imperative. Automotive, aerospace, marine, water treatment and other industries also make use of these screens for filtration, anti-dazzle screening, railings, ramps, walkways, window guards, architectural panels, drying racks and more. The open construction of
expanded metal allows for varied amounts of light, water, sound, air and debris to pass through it, improving visibility, safety and ventilation. Although this particular alloy may have a higher initial cost, stainless steel products often outlast alternative metalwork.
While other processes produce the same open grid patterns, metal expansion eliminates waste as the product is cut rather than punched or perforated. As it is a solid piece of metal, it is also more stable and has no welds, joints or seams to wear and work loose over time. To form this complete interlinking grid, stainless steel sheets or plates are fed into an automated metal expansion machine. The thickness, length and width of these stock forms should be carefully considered with regards to the final product as thickness will be significantly reduced during the expansion process. Likewise, the length of a piece of stainless steel can increase to as much as ten times that of the original. Once the sheet enters the machine, a series of knife-like dies slit the metal hundreds or even thousands of times in an alternating offset pattern. At the same time, the metal is drawn through hot rollers that stretch the metal, which causes the pre-cut holes to swell to the desired size. The solid metal sheet is transformed into a web of thin strands and bonds, creating an interconnecting structural network that distributes weight evenly along the entirety of the screen. While stainless steel may be manually expanded, computerized equipment is faster and more precise. The shape and percentage of the open area should be carefully considered with regards to the finished product or secondary operations.
