Stress Chloride Cracking

Posted by Tunstall Industries Inc. on 19th Dec 2022

Stress Chloride Cracking

Stress chloride cracking (SCC) is a type of corrosion that can occur in stainless steel water heaters when they are exposed to chlorides, such as those found in salt water or in chlorinated water. SCC can also occur when stainless steel is exposed to high stress, high temperatures, and high chloride concentrations.

SCC is a concern for stainless steel water heaters because it can lead to leaks and structural damage to the tank. The crack can appear in welds, areas of high stress, or around the opening of the tank where water is in contact with the steel. The crack can grow over time and cause leaks, it also can make the water heater to fail prematurely.

SCC can be prevented by selecting the right grade of stainless steel for the specific application, by reducing the chloride content in the water, by controlling the temperature, by reducing the stress and by proper welding techniques. For example, if a water heater will be used in an area with high chloride levels, it's recommended to choose a stainless steel grade that is more resistant to SCC, such as 316L or 317L stainless steel. This is why we only utilize high quality 316L stainless steel and also pickle and passivate them to add further protection.