Stainless steel products have countless properties, which is why they are the first choice for many industries. However, if you don’t take proper care of them, they can become contaminated. Although it may be hard to believe, stainless steel can also be susceptible to contamination.
Thanks to our extensive experience, at Tisco steel we are well placed to provide the necessary advice and instructions on the handling and use of stainless steel. So, continue reading our instructions below to avoid contamination of this great alloy.
How is stainless steel contaminated?
Find out how to avoid contamination of stainless steel
Stainless steel contamination occurs when the thin, passive film on the surface of the metal is permanently damaged, leading to corrosion. This surface contamination not only negatively affects the aesthetics of the steel, but also its performance, so avoiding this problem should be one of your company’s goals.
There are many possible sources of stainless steel contamination including manufacturing methods, chemical environment, temperature, product design, carbon steel particles, paint, grease, oil, dust, dirt, salt and free metals such as copper, zinc, lead, brass and aluminium.
In the steel industry, fabricators must follow very careful storage and handling practices in order to avoid contamination of stainless steel.
This contamination usually occurs, for example, when stainless steel is processed together with other materials such as carbon steel or when the same tools are used on the same workbench.
Because of this, companies working on the distribution and transformation of stainless steel must be aware of all the recommendations and procedures necessary for transport, handling, storage, operation and other appropriate actions with the aim of providing a product free of contamination.
Mistakes can be costly and difficult to correct, so prevention is always the better course of action.
What measures can I take?
Find out how to avoid contamination of stainless steel
Contamination of stainless steel is a major stage in the corrosion process. Here are some of the main steps you can take to avoid stainless steel contamination.
Careful storage. Mixed” fabrication shops have a high risk of contamination. Fabricators should have designated separate areas for their steel stock and fabrication processes.
When handling stainless steel, protect it with plastic or other packaging to prevent iron filings and other contaminants from settling on the surface and causing damage.
Stainless steel sheets should be stored horizontally in wooden boxes and covered to prevent contamination from airborne debris.
The possibility of iron or steel dust particles is eliminated. Loose and embedded iron particles are one of the most common sources of contamination. Many workshop activities, such as grinding, sandblasting, welding and machining, generate spatter, filings or dust, and these fragments can fall on stainless steel and contaminate it. It is therefore imperative that carbon steel is handled away from stainless steel.
Clean every cavity to avoid signs of corrosion. In addition, the stainless steel must be cleaned and disinfected in its entirety before any treatment is carried out.
Cleaners or acids with a pickling or passivating action (i.e. it will help with surface replenishment) are best used, but care should be taken as they can be aggressive.
The manufacturer should ensure that there is no contamination from shared tools, equipment and storage accessories. It uses those special tools to manipulate and process stainless steel. These tools must be properly sterilised and free from any contaminating agents.
If marks or marks need to be made on the stainless steel, they must be made with marks that can be easily removed.
The surface must be properly cleaned before welding.
In wet environments, it is best to use the same type of stainless steel.
Avoid mixing stainless steel joints with other metals. We recommend that you keep them separate.