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Zinc Embrittlement

How can stainless steel pipe can be protected against zinc embrittlement which may result from molten zinc dripping from galvanised steel during fire in a refinery.

Mishra
LTC - INDIA
2006

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2006

Hmm, avoid jury-rigging piping that leads to mechanical failures and fires.

Regarding the 1974 Flixborough disaster, zinc embrittlement seems only a secondary or tertiary cause. Leaking and ignition initiated events including prolonged impingement of a cyclohexane jet flame upon a stainless pipe. This decomposed cyclohexane within the pipe at 400-800 C, forming a brittle carbide network within the SS grain boundaries. I suggest also that burning cyclohexane reduced available oxygen and allowed melting, rather than oxidation, of zinc on the galvanized piping.

See "FLIXBOROUGH: THE EXPLOSION AND ITS AFTERMATH" by J. E. S. VENART, Trans IChemE, Part B, Process Safety and Environmental Protection, 2004, 82(B2): 105˜127.
http://www.icheme.org/about_icheme/medals/Venart2004.pdf

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
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