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Max needed inlet air temperature?
walk
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Posted on 02/09/2022 9:15 AM
I am planning to build fb roster, first one. I got borosilicate glass tube OD90 mm, ID80 mm and 310 mm height.
What is the max needed inlet air temperature? Does PTFE (250C) ok choice for glass tubes bottom unit?

Thank You
 
UmMerkur
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Posted on 02/09/2022 10:05 PM
Not sure on max inlet temp, I'm a drum guy, but came to warn you about PTFE.
While PTFE has a melting point of around 325C, it will start off-gassing around 250C. The F stands for Fluorine. You do not want that anywhere near something you eat/drink. In general I would avoid most plastics for high temperatures. PEEK may be an option depending on the temperature.
 
walk
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Posted on 02/09/2022 11:47 PM
Sounds logical, thank you!
 
walk
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Posted on 02/09/2022 11:57 PM
If glass and stainless steel are used, sealing or gluing may be required. Any suggestions on this?
 
renatoa
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Posted on 02/10/2022 2:04 AM
Kapton tape, on outer side of the glass/steep. Nothing inside.

Any seal/glue means chemicals... even they are rated for xxx degrees, almost none is rated for alimentary use at those degrees.

The only elastic thing that comes in my mind as usual in any house in a food usage over 200 C is the rubber gasket of the oven doors.
If you can find its formula... and availability for sale in tubes in liquid state... would be a great find !
 
walk
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Posted on 02/10/2022 2:27 AM
Thank you!
 
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