Chem treat stain, what exactly is it? This defect looks like a linear stain that is uniform throughout a coil. It is usually caused by mechanical failures at a chemical treatment’s wiping mechanism. It is primarily found on galvanized coils but can present on any coated steel coil, stainless steel coil or galvanneal coil. The color can vary on the stain ranging from light silver defect all the way to green and every color in between.
This steel defect can also be called longitudinal stain because of the direction it runs on the coil. You will find this defect throughout any coil that is affected. It’s not a highly common defect. Because the lines are manned as soon as the defect appears the red button is smacked and the line shuts down. That’s why you’re not normally going to find boatloads of steel coils with chem treat stain.
Even with chem treat stain some of our jobs and application have no issue with the steel as long as it’s not out of flat or buckled. As long as it’s straight, its either going into a mining application or buried in the back of a commercial dryer where it will never see the light of day.
Why does chem treat stain happen?
The defect usually occurs because of a clog in the line, a broken wiper or a miscalculation of the wiper roll. Surplus Metals Corp purchases defect and secondary coils and if you need to sell coils please reach out today.
Chem treat stains are going to be impossible to remove on such a large scale such as mill coils. However if you find yourself with stained pots, pans or a stained stainless steel sink – this could be just what your looking for to remove that!!