How is Perforated Sheet Metal Affected by the Weather?

Different grades of perforated metal can perform differently under different weather conditions. We go over some of the key information you need to know below.

What Is Perforated Metal?

‘Perforation’ is another word for ‘hole,’ so perforated metal is simple sheet metal with holes punched into it. These holes can be of various shapes and sizes, and can perform various functions and effects. Perforated metal is also called perforated sheet and perforated screen, and can be made from a variety of metals, including stainless steel, cold rolled steel, aluminium or other metals.

The mining industry first used perforated metal about 150 years ago. It used it to filter coal. Early efforts at making perforated metal sheets were inefficient. Labourers punched holes in sheets of metal by hand. Mechanised methods of punching holes have greatly increased efficiency and accuracy in this process.

How Is Perforated Metal Manufactured?

The process of manufacturing perforated metal begins with a metal sheet. Like the name suggests, the metal is thin and flat, much like a bed sheet in shape. It can be cut to any desired shape prior to, or after, perforation. The thickness of the metal is measured in mm in most of the world, but the United States uses ‘gauges.’ The larger the gauge, the thinner the metal.

Most metal perforation is done using a rotary pinned perforation roller. This device is comprised of a large cylinder with strong, pointed needles on the outside of it. As the sheet is passed under the rolling cylinder, the needles punch holes in it. In some processes, the needles are heated, and the sheet is paused under the roller just long enough to partially melt the edges of the new hole, decreasing sharpness.

The size and configuration of the hole patterns are determined by the roller chosen.

Die and punch perforating is another common method. Rather than using a continuous roller, die and punch uses a plate with needles on it, which is pressed down upon a sheet of metal, thereby punching holes in it. The surface is cleaned and smoothed afterwards by a sheer. This process is efficient and can quickly punch holes in large sheets.

The most advanced method of perforating metal is laser perforation. As you might assume, laser perforation requires a very expensive system. The benefits of it include extremely precise perforations which are heated during the process, similar to heated rotary needles. Consistency is very high.

How is Perforated Sheet Metal Used?

Modern architecture uses perforated metals often, and for a variety of purposes.

These sheets are excellent for sun protection, as they let limited light through small holes but don’t block it out completely like a solid sheet would. The perforations also allow ventilation, either natural or mechanically-driven, which further assists in climate control. Since the perforations can be punched in a variety of patterns and shapes, the purpose of these design elements is often mistaken for something purely decorative, whereas they function beyond that as well. Savings in heating, cooling, and other environmental controls are all gained by using this kind of simple design element.

Perforated sheets can function in much the same way, but for filtering out sound. The solid parts of the sheet block or deflect sound, while the holes allow some of it through.

Perforated sheets are also excellent for use as balustrades. They function almost as a solid barrier, but are lighter and still allow air flow and beautification through hole patterns and shapes.

Many industries use perforated metals. The food and beverage industries use them in wine vats, fish farms, sorting machines, fruit and veg presses, grain dryers, and even baking trays. The energy and chemical sectors use them for filters, mine cages, elevators, filters, coal washers, battery separator plates, centrifuges, and more. They are used in the automotive industry for oil filters, radiator grilles, engine ventilation, motorcycle silencers, and purifiers. Material development uses them for blast furnaces, cement slurry screens, safety cages, blast furnace screens, textile printers and felt mills, and more.

Perforated metal is also used a lot in structural steel projects according to Steelgram Fabrications LTD, which say they are among the most plentiful and widely used materials in most modern building construction.

Clear Weather Questions

As a result of these processes, there are clear differences in how we should view metal for outdoor and indoor use. We also need to consider things like vibrations, and climate factors (such as average rain acidity). This will all determine the final choice for your steel or other metal perforated panels, and you should always consult with a fabrication specialist before implementing anything.