Page 617 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

Appendix 581

A-9.
Vacuum Conversion
··------
Absolute Pressure Vacuum"
Torr Inches Hg Psia
Microns Hg Mm Hg (Abs.l Inches Hg

762 30.00 14.74
750 29.53 14.50 0.47
700 27.56 13.54· 2.44
650 25.59 12.57 4.41
600 23.62 11.60 6.38
550 21.65 10.64 8.35
500 19.68 9.67 10.32
450 l 7.72 8.70 12.28
400 15.75 7.74 14.25
350 13.78 6.77 16.22
300 11.81 5.80 18.19
250 9.84 4.84 20.16
200 7.84 3.87 22.13
150 5.91 2.900 24.09
100 3.94 l.934 26.06
50 1.97 .967 28.03
40 1.57 .774 28.43
30 1.181 .580 28.82
20 0.787 .3868
10 0.394 .1934
5 .197 .0967
4 .158 .0774
3 .1181 .0580
2 .0787 .0387
1.0 1000 1 .0392 .0193
0.5 500 0.50 .0197 Low Vacuum
l x 10- 1 too 0.10 .0039
5 x 10- 2 50 0.050
1 x 10- 2 10 0.010
5 x 10- 3 5 0.005
1 x 10- 3 0.001
1 X 10-•
l X JQ-G to High Vacuum
1 X 10- 6
to Very High Vac.
1 X I0- 9
1 x 10- 0
and beyond Ultra High Vac.
*Refers to 30'' Barometer
Conversion Factors:
millimeter = LOOO microns inch Hg = 25.4 mm Hg
1 Torr = I mm Hg Abs. I atmosphere = 14.7 pounds per sq. in.= 760 mm Hg= 29.92 in. Hg

Courtesy Pfaudler Co., Div. of Sybron Corp.