Stress Corrosion

Is it STRESS CORROSION.
We are having a Continuous Hardening & tempering Mesg belt furnace. Life of mesh belt , upon which the material is loaded is having very
short life, only 3-4months. very expensiec affair. Isn't it.
Gear blanks, wt.600-850gms, are loaded upon the mesh belt, it move inside the furnace set at 880C. at the end material falls into quench tank (sealed with oil stream) and mesh belt move down abd back into water bath.
mesh belt of steel SS 310.
We see corroded surface of the mesh belt. Slowly it get thin and breakdown.
What could be the reason. We checked down the water statsu it was having high chloride content not acidic...!!!
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I copied the following piece of information from a supplier of stainless steel (http://www.sandvik.com ):
Pitting and crevice corrosion The steel may be sensitive to pitting, even in solutions of a relative low chloride content. When continuous operation at room temperature, Sandvik 1200SA has good resistance to pitting providing that the belt is kept clean. To achieve even better resistance to pitting than Sandvik 1200SA, Sandvik 1000SA, which has a molybdenum content, is recommended.
Stress corrosion cracking Stress corrosion cracking, although occurring relatively infrequently, can be cause of failure in stainless steels. It occurs at temperature above about 70 C (160 F), if the steel is subjected to tensile stresses and comes into contact with certain solutions, particularly those containing chlorides.
Bosse
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Bosse, Thansk for the infromation. Its really useful. Regards Sunil Kumar

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wrote:

I copied the following piece of information from a supplier of stainless steel (http://www.sandvik.com ):
Pitting and crevice corrosion The steel may be sensitive to pitting, even in solutions of a relative low chloride content. When continuous operation at room temperature, Sandvik 1200SA has good resistance to pitting providing that the belt is kept clean. To achieve even better resistance to pitting than Sandvik 1200SA, Sandvik 1000SA, which has a molybdenum content, is recommended.
Stress corrosion cracking Stress corrosion cracking, although occurring relatively infrequently, can be cause of failure in stainless steels. It occurs at temperature above about 70 C (160 F), if the steel is subjected to tensile stresses and comes into contact with certain solutions, particularly those containing chlorides.
Bosse
And i always though chloride was alkaline, and that alkaline solutions were just as corrosive as acid ones !
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