|
 |
|
micron Hg |
torr/mm Hg |
mbar |
inches psi
absolute |
inches Hg
gauge |
inches Hg |
atm |
|
|
|
760,000 |
760 |
1013 |
14.7 |
29.92 |
0.0 |
1.0 |
|
750,000 |
750 |
1000 |
14.5 |
29.5 |
0.42 |
0.987 |
|
735,000 |
735.6 |
981 |
14.2 |
28.9 |
1.02 |
0.968 |
|
700,000 |
700 |
934 |
13.5 |
27.6 |
2.32 |
0.921 |
|
600,000 |
600 |
800 |
11.6 |
23.6 |
6.32 |
0.789 |
|
500,000 |
500 |
667 |
9.7 |
19.7 |
10.22 |
0.658 |
|
400,000 |
400 |
533 |
7.7 |
15.7 |
14.22 |
0.526 |
|
380,000 |
380 |
507 |
7.3 |
15.0 |
14.92 |
0.500 |
|
300,000 |
300 |
400 |
5.8 |
11.8 |
18.12 |
0.395 |
|
200,000 |
200 |
267 |
3.9 |
7.85 |
22.07 |
0.264 |
|
100,000 |
100 |
133.3 |
1.98 |
3.94 |
25.98 |
0.132 |
|
90,000 |
90 |
120 |
1.74 |
3.54 |
26.38 |
0.118 |
|
80,000 |
80 |
106.8 |
1.55 |
3.15 |
26.77 |
0.105 |
|
70,000 |
70 |
93.4 |
1.35 |
2.76 |
27.16 |
0.0921 |
|
60,000 |
60 |
80 |
1.16 |
2.36 |
27.56 |
0.0789 |
|
51,700 |
51.7 |
68.8 |
1.00 |
2.03 |
27.89 |
0.068 |
|
50,000 |
50 |
66.7 |
0.97 |
1.97 |
27.95 |
0.0658 |
|
40,000 |
40 |
53.3 |
0.77 |
1.57 |
28.35 |
0.0526 |
|
30,000 |
30 |
40.0 |
0.58 |
1.18 |
28.74 |
0.0395 |
|
25,400 |
25.4 |
33.8 |
0.4912 |
1.00 |
28.92 |
0.034 |
|
20,000 |
20 |
26.7 |
0.39 |
0.785 |
29.14 |
0.0264 |
|
10,000 |
10 |
13.33 |
0.193 |
0.394 |
29.53 |
0.0132 |
|
7,600 |
7.6 |
10.13 |
0.147 |
0.299 |
29.62 |
0.01 |
|
1,000 |
1 |
1.33 |
0.01934 |
0.03937 |
29.88 |
1.32x10-3 |
|
750 |
0.75 |
1.00 |
0.0145 |
0.0295 |
29.89 |
9.87x10-4 |
|
100 |
0.1 |
0.133 |
0.00193 |
0.00394 |
29.916 |
1.32x10-4 |
|
10 |
0.01 |
0.0133 |
1.93x10-4 |
3.94x10-4 |
29.9196 |
1.32x10-5 |
|
1 |
0.001 |
0.00133 |
1.93x10-5 |
3.94x10-5 |
29.91996 |
1.32x10-6 |
|
0.1 |
0.0001 |
1.33x10-4 |
1.93x10-6 |
3.94x10-6 |
29.91999 |
1.32x10-7 |
|
1 bar = 14.5 psi
con viscous flow
1 kg/cm2 = 14.223 psi
1 inch = 25.4 mm
1 cubic meter = 35.31 cubic feet
1 cubic foot = 28.32 liters
1 cubic foot = 7.4805 U.S. gallons
1 micron (1um) = 0.001 or 10-3mm
1 millimeter = 1000 um
1 micron = 1 millionth of a meter
con viscous flow
1 pascal = 7.5 microns
1 torr = 133.3 pascal
cu meters / hr to cu ft/ min x .589
cu/hr to liter/sec x 2.778
Mb to Pa x 100
torr to Pa x 133.322
liters to cu. ft. x .03531
cu ft/min to cu meter/hr x 1.697 |
conductance molecular flow (below 10-3 torr) through pipe
| C(pipe) = |
11.6 D(cubed) |
(Expressed as liters/sec) |
|
L |
D&L in cm. | pump down time
|
T = |
2.3V |
T= Time in sec. V=system volume liters |
|
Sn |
Sn=net pumping speed in liters/sec |
| |
|
Sn = |
sp c |
SP= pump speed |
|
sp+c |
C=conductance of rough line (in viscous flow) |
| conductance (viscous flow)
|
D=tube diam.in cm
L=tube length in cm
Pavg=sum of pressure at tube ends divided by 2 in torr | C=0.033 (D4/L) Pavg liters/sec (Simplified for air @ 20deg.c) |
| | |
