Re: inductive heaters

To: neon-l@netcom.com
Subject: Re: inductive heaters
From: neonmc@earthlink.net (Morgan Crook)
Date: Mon, 22 Apr 1996 16:23:26 -0700
Reply-To: neon-l@netcom.com
Sender: owner-neon-l@netcom.com

>>
>What is the "reabsorption" temp to a tube and are there other variables
>that come into play?  By that I'm wondering, since some phosphers are more
>sensitive to absorbing moisture, etc., do they reabsorb crud at different
>temps?
>
>Tom U.
>
>
>
Tom,
one simple way to view "readsorption" is that it occurs at the same temp
that it was liberated.  If you check out Miller it (kinda) says that
everything is being released at around 175 C. (sorta)
Anyway (if you take this rough model), crap then can reattach itself to the
glass at this same temp when cooling.  If you were to use an IR temp gauge
you may be suprised to find that it takes only 20 or 30 secs for the tube to
cool to this point when heated to 225 C.  Really makes you think about the
importance of this window of opertunity (how narrow it is) and how important
it is toget as much stuff out as possible QUICKLY.
I think most of the stuff in phosphors is water.  From what I understand (or
don't as the case may be) is that phosphor "production" is done at temps
much higher than even glass bending temps, so we never get to the
"outgassing" temp of the phosphors.
This is a pretty rough explination.  There are some good phosphor people on
the list... maybe they will add (or correct)
Morgan