Bev
I agree PFCs are the worst climate changers (with SF6) that exist. Some
of them are over 10,000 times worse than CO2. As a rule of thumb, 6
freezing cans which contain a PFC gas would have as much effect on
climate change as a medium car over its whole lifetime (horrific
thought). Furthermore, there will still be the contents of two of those
cans in the atmosphere 40-odd generations from now (assuming man lives
for another 40 generations!). However, I think most freezing cans
contain HFC-134a, which is bad enough but not as bad as PFCs. Some may
still contain HCFC-22 which is just as bad AND an ozone depleter, to
boot, but is not phased out under the Montreal Protocol until 2010 (some
countries may phase it out sooner).
Brian
Bev Christian wrote:
>
> Jean-Luc and other TechNetters,
> I just want to point out that I was absolutely NOT talking about CFC's
> (chlorofluorocarbons), which of course I know are banned. I am concerned
> about fully fluorinated compounds - no chlorine, no hydrogen, just
> CF3(CF2)nCF3 and branched chain equivalents. I will shut up if someone can
> tell me about cooling sprays that are not based on CF compounds - or on
> relatively friendly gases like CO2 and N2.
>
> Bev Christian
> Research in Motion
>
> -----Original Message-----
> From: [log in to unmask] [mailto:[log in to unmask]]
> Sent: April 25, 2002 10:02 AM
> To: [log in to unmask]
> Subject: Re: [TN] Freeze Spray Trouble Shooting
>
> Nice equipment but well the original post was about freezing electronic
> component, and not to cool down dry machining operations.
>
> For electronic application, the chemical used must be clean and not have
> any contaminants in it, otherwise the electronic won't like it.
> I see that Exair Vortex include a dust and oil filter but is it clean
> enough for electronic parts ?
> Another thing is that also it is small compared to a milling machine, the
> Vortex is still quite bulky to use in a lab, specially with the hose for
> the shop air.
>
> Aother thing to consider is that most freeze spray are specified with low
> electrostatic charge, because charge build-up could destroy components.
>
> As for Bev Christian's concern about CFC, there are Freeze Spray without
> CFC.
>
> Jean-Luc Lehmann
>
> SteveZeva@AOL
> .COM To: [log in to unmask]
> Sent by: cc:
> TechNet Subject: Re: [TN] Freeze Spray
> Trouble Shooting
> <[log in to unmask]
> ORG>
>
> 25.04.02
> 02:44
> Please
> respond to
> "TechNet
> E-Mail
> Forum.";
> Please
> respond to
> SteveZeva
>
> Hi David!
>
> That's why this list is so valuable! They are still around!
> Http://www.exair.com
>
> Thanks!
>
> -Steve Gregory-
>
> Bev, Years ago (about 7) there was a company selling hand held Vortex
> generators that plugged into 100 psi shop air.
> These little jewels put out -40 degree C air as long as there was 100 psi
> available. It also had to be dry nonlubed air. The company was called
> EXAir. I don't know if they are still around. David A. Douthit
> Manager
> LoCan LLC
>
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