The process of perforating metal sheets and panels has been around for nearly 150 years and was initially developed as a way of manufacturing durable filters and sorters for use in the mining industry. In the late 19th century, coal was separated using presses with screens made of canvas or wire, which tended to break or tear easily and needed constant replacement. Metal screens proved excellent for filtering mining materials and their use soon expanded well beyond their original function.
Today, perforated metal panels are used by architects for a wide variety of applications, from decorative lighting fixtures and signs to industrial filtration screens and acoustical panels. As the uses for perforated metals have evolved, so has the perforating process itself. Manufacturers now utilize specialized techniques to achieve the intended perforation patterns and sizes according to material, width of the panel, and customer specifications.
The original metal perforation process was crude, as would be expected. The first perforators punched holes individually into the metal but quickly realized the inefficiency and inconsistency of this method. Soon perforations were made by simultaneously using many punching needles which were arranged in specific patterns and widths.
Today’s perforation methods would probably be unrecognizable to earlier manufacturers. The best perforating companies have at their disposal several techniques to precisely perforate metal sheets and panels.
The most common tool used today is the rotary pinned perforation roller. This is a large cylinder with sharp, pointed needles on the exterior to punch holes in the metal. These needles can be heated in order to melt the metal and provide a ring of extra reinforcement around the perforation. Pinned rollers are used for making a wide range of hole sizes.
Die and punch perforating is another method which is relatively simple. A sheet with needles is pressed onto the metal panel in such a way that the “chad” is left hanging on the opposite side (think Florida ballots, circa November 2000). These chads are then sheared and the surface is smoothed. The die and punch process allows for fast perforating over a large surface area of metal screens and panels.
Laser perforating is the most recent development in perforating technology and also the most expensive and complex. The perforations which are made with this process have much of the same characteristics as hot needle perforations but are far more precise and consistent.
Architects and building developers have never had more choices when it comes to perforated metal panels and screens for use in their projects. More and more structures are utilizing these materials in creative and innovative ways to meet their clients’ needs.