Perforated tubes’ standard perforated patterns are straight, staggered or oblong staggered, but many manufacturers are able to produce tubes with custom perforated patterns.
Their open hole area size is determined by the minimum size of the particulates being trapped within the tube. Though the perforations are usually round, some tubes are made with square or slot-shaped holes.
Perforated metal tubes, unlike many other perforated metal varieties, are infrequently used for decorative purposes. They are sometimes used in pieces of industrial art, but they are generally restricted to use as industrial utilities.
The most visible applications of perforated metal tubes are exhaust systems. Wide, corrosion-resistant perforated exhaust pipes are standard on most large trucks and in some sport cars and high-performance utility vehicles. Perforated metal tubes are also used in Bunsen burners and other gas-fired heating apparatus.
During the perforated metal tube manufacturing process, every tube is inspected for hole diameter accuracy. The perforated pattern in tubes is made by machines called punch presses, which cut holes in rolled sheet metal.
For many years, punch presses were operated manually by technicians. Today, punch presses are often controlled by computer software, which is called Computer Numerical Control software.
Using CNC punch presses is less time-intensive than manual punch pressing and requires a lower investment in labor costs. Whether a punch press is manual or automatic, it involves a ram or stamp that exerts pressure on a metal, which makes hole-shaped cutouts in the sheet.
Perforated tubes are most often made of stainless steel or carbon steel, although aluminum is sometimes used. After perforation, the sheet metal is cut to size and welded or fastened into the tube form.
Perforated tubing manufacturers often provide end forming operations, which include sizing, reducing, flaring and bulging. In high strength applications, the metal may be strengthened by tempering, quenching or a galvanizing processes.