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[MW:13306] RE: 13288] To increase hardness of Heat Exchanger fin

By Materials & Welding
Hi Priyanka,
 
What are the design conditions for the air cooled finned exchangers, e.g operating media, design temperature , materials of construction? .Is the intended application is for refinery or other type of plants ?
 
Generally  pure aluminum is popular as fin material, however it does not offer much scope for improvement of hardness as this this material  is not heat treatable. Improvement of hardness through surface coating or thermal spray may impair corrosion resistance and the heat transfer coefficient.  

Below are some extracts on recommended material of construction for fin tubes, typically for oil and gas applications from various appropriate specifications.
 
Thanks


Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist & Consultant
Ontario,Canada.
Email-pgoswami@sympatico.ca,
pgoswami@quickclic.net

  • Tubes with embedded aluminum fins or hot-dip galvanized steel fins, applicable up to a maximum operating temperature of 360 °C, should be used. Hot-dip galvanised steel fins shall not be used on austenitic steel tubing.
 



  • -----Original Message-----
    From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Priya Deshmukh
    Sent: Saturday, December 24, 2011 1:24 AM
    To: materials-welding
    Subject: [MW:13288] To increase hardness of Heat Exchanger fin

    To,

    All.

    Please provide me the procedure to increase the hardness of fin material without affecting its thermal conductivity.

    May be some spray or liquid may be available, by spraying or dipping the fins into the liquid the hardness can be increased.

    Thanks,

    --
    Priyanka Deshmukh

    --
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