Stainless steel relies on its protective oxide film to protect it during service. If this film is damaged during fabrication or installation, the stainless steel will be more vulnerable to corrosion. This is why it’s so important that any contamination is avoided during the manufacturing processes, and that any effects of welding, such as splatter, that might affect the surface of the steel are removed.
As a general rule, the cleaner and smoother the surface finish, the higher the corrosion resistance. This is not only relevant during manufacture, but also applies to transport and storage after fabrication. Stainless steel should be stored in such a way that the surface isn’t scratched or scored in any way. In cases where plates or sheets have to be stored vertically, they should be separated from each other using timber spacers or even pieces of cardboard so that they don’t touch each other, as this could cause abrasion. Ideally, all stainless steel should be kept under some kind of protective cover while in storage.
The reason why it’s so important to protect stainless steel from potential crevices or gouges on its surface is because this kind of damage provides a perfect place for corrosion to start. Scratches could also contain contaminants from the object that caused the damage.
Common contaminants include a number of every day products, including salt, oil, grease, fingerprints, paint and chalk marks. These can all contain products that could cause localised corrosion. They can also lessen the efficacy of electrochemical cleaning.
Occasionally, residual adhesive from protective plastic coatings or tape remains behind after the tape or plastic has been removed. This should be removed as soon as possible using an organic solvent as, if they are left to harden, they can form sites for corrosion and can be very difficult to remove.
By far the most common contaminant, which is encountered frequently during fabrication, is iron, either embedded or in the form of loose particles. Iron rusts very quickly and can cause corrosion.
Welding also presents a number of challenges as its high temperature characteristics create a host of potential corrosion issues from splatter, slag and stray arc strikes.
Stainless steel is a robust and forgiving material, but good manufacturing processes can only serve to further enhance these characteristics. The stainless steel industry always strives to deliver finished products that are in a passive condition, meaning they are free of corrosive reactions, so that customer satisfaction is guaranteed.
Steelmor is a respected stainless steel company that’s been manufacturing and supplying stainless steel products for over 40 years. We adhere to strict fabrication, storage and transport protocols to ensure all your products reach you in perfect condition. Speak to us today about how we can help you with your next project.