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watana
30-12-2001, 05:25 PM
please advise how to identify between the unit "micron" and "torr", how to convert them?

thank you

Prof Sporlan
31-12-2001, 04:48 PM
A 'torr' is the pressure exerted by a 1 mm column of mercury. The Prof hasn't seen the term 'torr' used much... 'mm Hg' seems more common. A 'micron' is the pressure exerted by a 1 micron (one millionth of a meter) column of mercury.

Since there are exactly 1000 microns to the millimeter, the conversion from torr to microns is easy to remember:

1 torr = 1000 microns

Relating these units to atmosphere:

1 atm = 760 mm Hg (torr)
1 atm = 760,000 microns

Mike Hopkins
14-01-2002, 02:56 AM
Hey Prof,
Frequently I run across converting inches hg to psia and vice versa, have you any handy formulas for this.
I use one for inches hg to psia = subtract inches hg from 29.9
divide result by 2.04 to get PSIA.

Mike Hopkins

nadeem majeed
07-11-2008, 01:32 PM
when we vacuum the a/c unit maximum it goes to -1 bar can we get the vacuum more than -1 bar on same atmospheric pressure

nike123
08-11-2008, 11:08 PM
when we vacuum the a/c unit maximum it goes to -1 bar can we get the vacuum more than -1 bar on same atmospheric pressure

You cant go below-1 bar on any atmospheric pressure. That is absolute vacuum!
But because of inaccurate gauge, you may see lower pressure!

dogma
09-11-2008, 09:05 AM
please advise how to identify between the unit "micron" and "torr", how to convert them?

thank you


buy 1 of these mate.


http://www.toolstop.co.uk/cps-vg200-vacrometer-digital-vacuum-gauge-p1327


:)

Peter_1
09-11-2008, 09:55 AM
Nadeem, don't make twice the same post in a different section.
Therefore I will close this one and suggest you go to http://www.refrigeration-engineer.com/forums/showthread.php?p=125283#post125283