How to Deal With The Different Forms of Corrosion On Stainless Steel Tubes

Corrosion is among the most common problem that affects stainless steel tubes. The good news is that dealing with corrosion on stainless steel tubes can be done in the individual capacity. This article provides useful information about the restoration of stainless steel for a DIY homeowner. Read on.

Differentiating between stainless steel and coated stainless steel

Steel tubes around the home can be made of actual stainless steel, or they can be made of a different material coated with stainless steel. You need to establish whether the steel tube in question is made of stainless steel or it has been coated using stainless steel before undertaking any repairs meant to combat corrosion.

Differences between coated steel and stainless steel products include the fact that stainless steel products have a uniform silver colour all around, while steel-coated products are often black on the back and only have a silver appearance on their front side. This is the easiest way for laymen to tell what type of steel tube they're working with.

Types of corrosion that affect steel tubes and how to avoid them

Steel tubes may suffer various forms of corrosion.

Pitting corrosion

Pitting corrosion refers to a situation in which the action of harmful chemical compounds results in the formation of cavities on the steel surface of the tube. Harmful compounds, e.g. chloride ions, attack the protective coating on the steel tube leading to degradation. This type of corrosion is dangerous because it deeply damages the metal structure of steel tubes. Pitting corrosion can be prevented by polishing steel tubes to increase their resistance. 

Crevice corrosion

Crevice corrosion, which is also common with steel tubes, occurs when there is limited oxygen supply to the surface of the steel tube, limiting the formation of the protective layer on the tube and thereby making it more vulnerable to corrosion. This type of corrosion can be avoided through DIY sealing of crevices. If the extent of corrosion is severe, you may have to upgrade to a stainless steel grade that is more resistant to corrosion.

Galvanic corrosion

Lastly, stainless steel tubes may also suffer galvanic corrosion, which happens when a stainless steel tube is allowed to be in contact with a different metal in the presence of an electrolyte solution such as water. The two metals and the electrolyte solution form a galvanic cell of sorts. The formation of this "cell" results in the accelerated galvanic corrosion of the weaker metal. To correct and avoid this problem in future, you should create a barrier between the two metals using non-metallic corrosion insulators such as rubber.