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Metal finishing Q&As since 1989

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Even Hastelloy Rusts in Chloride-Rich Glass Mfg. Environment

We are manufacturing glass in corrosive environment of Chlorides . Our machine are rusting even in spite of using Hastelloy material. After this rusting is clean within few days again the rust is appearing. How can I avoid rust formation? Any one having information on rust or corrosion prevention, please forward me .

S Singh
MANUFACTURING - KANPUR, UP, India
2004

Hastelloy and its relatives are alloys of either nickel or cobalt with additions formulated to form a protective layer. Both base metals are attacked by chlorides, so eventually when this layer is affected the alloy will be attacked. Though there may be other alternatives, the most common totally immune are precious metals and some plastics (these limited by temperature and mechanical properties).

Guillermo Marrufo
Monterrey, NL, Mexico
2004

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Dear Mr. Singh,

I am not well aware of glass manufacturing process and do not know where from chloride atmosphere is generating. However to avoid further corrosion clean the equipments free from any rust and oil, apply suitable (anti-corrosive grade) of epoxy or PU system.

PRABHAKAR GUPTA
- Kanpur, U.P., India
2004