Steel’s versatility has been hardly beaten by any other metal so far. Thanks to its adaptable composition, malleability and low-cost, steel is a metal that shows little chances of being downgraded. Its range of uses includes roof and wall panels, domestic appliances, gutters and downspouts, leaf and debris prevention, garage and entry doors, ceiling tiles, back splashes, furniture, etc. Yet, why do we not notice the presence of such metal despite it being everywhere? The extremely large range of the metal’s appearances may explain this matter.

One of the most common uses of steel is in the form of PPGI for coating purposes. Generally speaking, PPGI is a good choice when cost-effectiveness and aesthetics matter. It consist in a sheet of steel, plus a galvanization layer and a further paint coat on top. Yet the process is not as simple as gluing layers together.

At SMC, the galvanized iron coil is firstly cleaned at the decreasing tank, where oil and dust are chemically removed. Secondly, a basic layer of paint, called primer, is applied on the pre-treated chemical coat. The requested colours and specifications of paint are then applied on both sides of the primer coated coil to complete the painting work. The primer coating is cured in a oven and cooled at the primer water quench. Similarly, the finish oven and finish water quench also serve to ensure that the final layer of finishing paint applied is completely cured and cooled.

A great deal of attention has to be paid at each of these stages. For instances, the galvanized layer -beneath the paint- plays a significant role already. Zinc corrosion can happen where the paint is damaged. Usually, chances of cracks to form in the paint coating are high if the panel designed has small sharp edges. Large bend radius designs are preferred. Another issue is ‘oil canning’ when wide flat panels start to show a wavy appearance.

Beyond manufacture precision, the item’s destination of use has to be carefully considered -especially for outdoor purposes. The amount and intensity UV rays exposure largely affects the lifespan of the product. Flatter roofs on a building located at low latitudes mean high UV exposure, so good primer and topcoat are required. Moisture contact, the acidity of the rain,  wind direction, pollution fallout from nearby industrial plants and effects of salt near close to sea coast locations are all elements that have to be taken into account.

 At SMC we approximately supply 5,000 ton of output monthly for each line. We are aware that good PPGI products can reach a lifespan of over 20 years. Thus, with 15 years of experience in the field, we can supply you with Pre-painted Galvanized Steel Coil, Diamond Embossed PPGI, Printing PPGI and many other products. For further information and enquiry,