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Helium Leak Test Method

Spray
Sniffer
Bombing
Vacuum Chamber Inside in
Vacuum Chamber Inside Out
Pressure Accumulation

Vaccum Pump Comparison Chart
DRY TYPE VACUUM PUMP SYSTEM
STEAM EJETOR SYSTEM
OIL ROTARY VACUUM PUMP SYSTEM
WATER SEALED VACUUM PUMP SYSTEM
Ultimate Pressure
Available until high vacuum (100-10-Torr), No chance of ultimate pressure at high temperature in Summer
As water temperature. rises at summer, ultimate pressure falis.
Emulsifying water and oil, ultimate pressure falls
It's limited for use under low vacuum (60-500 Torr)
Environment
Sewage problem is eliminated
Sewage
Waste oil
Sewage
Processing capacity (Pump capacity)
Capacity from small to high is used for specific application
For high capacity
The capacity is limited. For small capacity mostly
High capacity is available but with big expenses of power and investment
Utility
Only Little space needed for installation, Easy to utilize free space
Wide space is needed for installation
The space for installation is quite small so some free space is available.
Wide space is needed for installation
Operation cost
At same capa, 50% of operating cost can be saved.
Huge operating cost is spent due to excess utility
More electric power is needed compared to processing capacity
As capacity is getting bigger. power cost and operating cost are needed more.
Maintenance
Simple manipulation and maintenance at processing.
Difficult maintenance because of many individual facilities
Vacuum oil is needed to change often. Difficult maintenance
Difficult maintenance because of many individual facilities

Water Vapor Pressure Table

For this subsection, the following units conversions are applicable.

“F=9/5°C+32

To convert milimeters of mercury to pounds-force per square inch, multiply by 0.01934

VAPOR PRESSURE OF WATER ICE FORM -15 TO 0 °C
1°C
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
-14
1.361
1.348
1.336
1.324
1.312
1.3
1.288
1.276
1.264
1.253
-13
1.49
1.477
1.464
1.45
1.437
1.424
1.411
1.399
1.386
1.373
-12
1.632
1.617
1.602
1.588
1.574
1.559
1.546
1.532
1.518
1.504
-11
1.785
1.769
1.753
1.787
1.722
1.707
1.691
1.676
1.661
1.646
-10
1.95
1.934
1.916
1.899
1.883
1.866
1.849
1.833
1.817
1.8
-9
2.131
2.112
2.093
2.075
2.057
2.039
2.021
2.003
1.985
1.968
-8
2.326
2.306
2.285
2.266
2.246
2.226
2.207
2.187
2.168
2.149
-7
2.537
2.515
2.493
2.472
2.45
2.429
2.408
2.387
2.367
2.346
-6
2.765
2.742
2.718
2.695
2.672
2.649
2.626
2.603
2.581
2.559
-5
3.013
2.987
2.967
2.937
2.912
2.887
2.862
2.838
2.813
2.79
-4
3.28
3.252
3.225
2.198
3.171
3.144
3.117
3.091
3.065
3.039
-3
3.568
3.539
3.509
3.48
3.451
3.422
3.393
3.364
3.336
3.308
-2
3.88
3.848
3.816
3.785
3.753
3.722
3.691
3.66
3.63
3.599
-1
4.217
4.182
4.147
4.113
4.079
4.045
4.012
3.979
3.946
3.913
0
4.579
4.542
4.504
4.467
4.431
4.395
4.359
4.323
4.587
4.252
VAPOR PRESSURE OF WATER ICE FORM -16 TO 0 °C
t°C
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
-15
1.436
1.425
1.414
1.402
1.39
1.379
1.368
1.356
1.345
1.334
-14
1.56
1.547
1.534
1.522
1.511
1.407
1.485
1.472
1.46
1.449
-13
1.691
1.678
1.665
1.651
1.637
1.624
1.611
1.599
1.585
1.575
-12
1.834
1.819
1.804
1.79
1.776
1.761
1.748
1.734
1.72
1.705
-11
1.987
1.971
1.955
1.939
1.924
1.909
1.893
1.878
1.863
1.848
-10
2.149
2.134
2.116
2.099
2.084
2.067
2.05
2.034
2.018
2.001
-9
2.326
2.307
2.289
2.271
2.254
2.236
2.219
2.201
2.184
2.167
-8
2.514
2.495
2.475
2.456
2.437
2.418
2.399
2.38
2.362
2.343
-7
2.715
2.695
2.674
2.654
2.633
2.613
2.593
2.572
2.553
2.533
-6
2.931
2.909
2.887
2.866
2.843
2.822
2.8
2.778
2.757
2.736
-5
3.163
3.139
3.002
3.092
3.069
3.046
3.022
3
2.976
2.955
-4
3.41
3.384
3.334
3.334
3,309
3.284
3,259
3.234
3.211
3.187
-3
3.673
3.647
3.593
3.593
3.567
3.54
3.512
3.487
3.461
2.436
-2
3.956
3.927
3.871
3.871
3.841
3.813
3.785
3.757
3.73
3.702
-1
4.258
4.227
4.165
4.165
4.135
4.105
4.075
4.045
4.016
3.986
0
4.579
4.546
4.48
4.48
4.448
4.416
4.385
4.353
4.32
4.289

Computed form the above table with the aid of the thermodynamic quation.
log10 pw-1.1489t pi 273.1+t -5/2 -8/2 –1.330×10 +9.084×10

VAPOR PRESSURE OF LIQUID WATER FORM 0 TO 100 °C
t°C
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0
4.579
4.613
4.647
4.681
4.715
4.75
4.785
4.82
4.855
4.89
1
4.926
4.962
4.998
5.034
5.07
5.107
5.144
5.181
5.219
5.256
2
5.294
5.332
5.37
5.408
5.447
5.486
5.525
5.565
5.605
5.645
3
5,685
5.725
5.766
5,807
5.848
5.889
5.931
5.973
6.015
6.058
4
6.101
6.144
6.187
6.23
6.274
6.318
6.363
6.408
6.453
6.498
5
6.543
6.589
6.635
6,681
6.728
6.775
6.822
6.869
6.917
6,965
6
7.013
7.062
7.111
7.16
7.209
7.259
7.309
7.36
7.411
7.462
7
7.513
7.565
7.617
7,669
7.722
7.775
7.828
7.882
7.936
7.99
8
8.045
81
8.155
8.211
8.267
8323
8.38
8.437
8.494
8.551
9
8.609
8.668
8.727
8.786
8.845
8.905
8.965
9,025
9.086
9.147
VAPOR PRESSURE OF LIQUID WATER FORM 0 TO 100 °C
t°C
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
10
9.209
9.211
9.333
9.365
9.468
9.521
9.595
9.649
9.714
9.779
11
9.844
9.931
9.976
10.042
10.109
10.176
10.244
10.312
10.380
10.449
12
10.518
10.588
10.658
10.728
10.799
10.870
10.941
11.013
11.085
11.185
13
11.231
11.305
11.379
11.453
11.528
11.602
11.678
11.754
11.831
11.908
14
11.987
12.065
12.144
12.223
12.302
12.382
12.462
12.543
12.624
12.706
15
12.788
12.871
12.953
13.037
13.121
13.205
13.290
13.375
13.461
13.547
16
13.634
13.721
13.809
13.898
13.987
14.076
14.166
14.256
14.347
14.438
17
14.530
14.622
14.715
14.809
14.903
14.997
15.092
15.188
15.284
15.380
18
15.477
15.575
15.673
15.772
15.871
15.971
16.071
16.171
16.272
16.374
19
16.477
16.581
16.685
16.789
16.894
16.999
17.105
17.212
17.319
17.427
20
17.535
17.644
17.753
17.863
17.974
18.085
18.197
18.309
18.422
18.536
21
18.651
18.767
18.883
19.000
19.118
19.236
19.355
19.475
19.595
19.716
22
19.837
19.959
20.081
20.204
20.328
20.452
20.577
20.703
20.829
20.956
23
21.084
21.213
21.342
21.472
21.603
21.734
21.866
21.999
22.132
22.266
24
22.401
22.537
22.674
22.811
22.949
23.088
23.227
23.368
23.509
23.651
25
23.794
23.937
24.081
24.226
24.372
24.518
24.665
24.813
24.362
25.112
26
25.263
25.414
25.566
25.719
25.873
26.027
26.182
26.338
26.495
26.653
27
26.812
26.971
27.131
27.292
27.454
27.617
27.781
27.946
28.111
28.278
28
28.446
28.614
28.783
28.953
29.124
29.296
29.469
29.643
29.818
29.994
29
30.171
30.349
30.528
30.708
30.889
31.071
31.253
31.438
31.623
31.809
30
31.996
32.185
32.375
32.566
32.758
32.951
33.145
33.340
33.536
33.733
31
31.931
34.130
34.330
34.532
34.734
34.937
35.141
35.346
35.552
35.759
32
35.967
36.176
36.386
36.597
36.809
37.022
37.236
37.451
37.667
37.884
33
38.102
38.321
38.541
38.762
38.984
39.207
39.431
39.656
39.882
40.109
34
40.337
40.566
40.796
41.027
41.259
41.492
41.726
41.961
42.197
42.434
35
42.672
42.911
43.151
43.392
43.634
43.877
44.121
44.366
44.612
44.859
36
45.107
45.356
45.606
45.857
46.109
46.362
46.616
46.871
47.127
47.384
37
47.342
47.901
48.161
48.422
48.684
48.947
49.211
49.476
49.742
50.009
38
50.277
50.546
50.816
51.087
51.359
51.632
51.906
52.181
52.457
52.734
39
53.012
53.291
53.571
53.852
54.134
54.417
54.701
54.986
55.272
55.559
40
55.874
56.136
56.426
56.717
57.009
57.302
57.596
57.891
58.187
58.484
41
58.782
59.081
59.381
59.682
59.984
60.287
60.591
60.896
61.202
61.509
42
61.817
62.126
62.436
62.747
63.059
63.372
63.686
64.001
64.317
64.634
43
64.952
65.271
65.591
65.912
66.234
66.557
66.881
67.206
67.532
67.859
44
68.187
68.516
68.846
69.177
69.509
69.842
70.176
70.511
70.847
71.184
45
71.522
71.861
72.201
72.542
72.884
73.227
73.571
73.916
74.262
74.609
46
74.957
75.306
75.656
76.007
76.359
76.712
77.066
77.421
77.777
78.134
47
78.492
78.851
79.211
79.572
79.934
80.297
80.661
81.026
81.392
81.759
48
82.127
82.496
82.866
83.237
83.609
83.982
84.356
84.731
85.107
85.484
49
85.862
86.241
86.621
87.002
87.384
87.767
88.151
88.536
88.922
88.309
50
89.697
90.086
90.476
90.867
91.259
91.652
92.046
92.441
92.837
93.234
60
149.38
150.43
151.77
153.38
155.31
157.54
159.95
162.47
165.17
168.01
70
223.7
226.9
230.4
234.1
238.0
242.1
246.3
250.6
255.0
259.6
80
335.1
340.7
346.9
353.5
360.6
368.2
376.3
384.9
394.0
403.7
90
525.76
527.76
529.77
531.78
533.80
535.82
537.86
539.9
541.95
544.0
91
546.05
548.11
550.18
552.26
554.35
556.44
558.53
560.64
562.75
564.87
92
566.99
569.12
571.26
573.4
575.55
577.71
579.87
582.04
584.22
586.41
93
588.6
590.8
593.0
595.21
597.43
599.66
601.89
604.13
606.38
608.64
94
610.90
613.17
615.44
617.72
620.01
622.31
624.61
626.92
629.24
631.57
95
633.90
636.24
638.59
640.94
643.3
645.67
648.05
650.43
652.82
655.22
96
657.62
660.03
662.45
664.88
667.31
669.75
672.2
674.66
677.12
679.69
97
682.7
684.85
687.04
689.04
692.05
694.57
697.1
699.63
702.17
704.71
98
707.27
709.83
712.4
714.98
717.56
720.15
722.75
725.36
727.98
730.61
99
733.24
735.88
738.53
741.18
743.85
746.52
749.20
751.89
754.58
757.29
100
760.0
762.72
765.45
768.19
770.93
773.68
776.44
779.22
782.0
784.78
101
787.57
790.37
793.18
796.0
798.82
801.66
804.5
807.35
810.21
813.08
t°C 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
109.2099.2119.3339.3659.4689.5219.5959.6499.7149.779
119.8449.9319.97610.04210.10910.17610.24410.31210.38010.449
1210.51810.58810.65810.72810.79910.87010.94111.01311.08511.158
1311.23111.30511.37911.45311.52811.60211.67811.75411.83111.908
1411.98712.06512.14412.22312.30212.38212.46212.54312.62412.706
1512.78812.87112.95313.03713.12113.20513.29013.37513.46113.547
1613.63413.72113.80913.89813.98714.07614.16614.25614.34714.438
1714.53014.62214.71514.80914.90314.99715.09215.18815.28415.380
1815.47715.57515.67315.77215.87115.97116.07116.17116.27216.374
1916.47716.58116.68516.78916.89416.99917.10517.21217.31917.427
2017.53517.64417.75317.86317.97418.08518.19718.30918.42218.536
2118.65118.76718.88319.00019.11819.23619.35519.47519.59519.716
2219.83719.95920.08120.20420.32820.45220.57720.70320.82920.956
2321.08421.21321.34221.47221.60321.73421.86621.99922.13222.266
2422.40122.53722.67422.81122.94923.08823.22723.36823.50923.651
2523.79423.93724.08124.22624.37224.51824.66524.81324.96225.112
2625.26325.41425.56625.71925.87326.02726.18226.33826.49526.653
2726.81226.97127.13127.29227.45427.61727.78127.94628.11128.278
2828.44628.61428.78328.95329.12429.29629.46929.64329.81829.994
2930.17130.34930.52830.70830.88931.07131.25431.43831.62331.809
3031.99632.18532.37532.56632.75832.95133.14533.34033.53633.733
3133.93134.13034.33034.53234.73434.93735.14135.34635.55235.759
3235.96736.17636.38636.59736.80937.02237.23637.45137.66737.884
3338.10238.32138.54138.76238.98439.20739.43139.65639.88240.109
3440.33740.56640.79641.02741.25941.49241.72641.96142.19742.434
3542.67242.91143.15143.39243.63443.87744.12144.36644.61244.859
3645.10745.35645.60645.85746.10946.36246.61646.87147.12747.384
3747.64247.90148.16148.42248.68448.94749.21149.47649.74250.009
3850.27750.54650.81651.08751.35951.63251.90652.18152.45752.734
3953.01253.29153.57153.85254.13454.41754.70154.98655.27255.559
4055.84756.13656.42656.71757.00957.30257.59657.89158.18758.484
4158.78259.08159.38159.68259.98460.28760.59160.89661.20261.509
4261.81762.12662.43662.74763.05963.37263.68664.00164.31764.634
4364.95265.27165.59165.91266.23466.55766.88167.20667.53267.859
4468.18768.51668.84669.17769.50969.84270.17670.51170.84771.184
4571.52271.86172.20172.54272.88473.22773.57173.91674.26274.609
4674.95775.30675.65676.00776.35976.71277.06677.42177.77778.134
4778.49278.85179.21179.57279.93480.29780.66181.02681.39281.759
4882.12782.49682.86683.23783.60983.98284.35684.73185.10785.484
4985.86286.24186.62187.00287.38487.76788.15188.53688.92289.309
5089.69790.08690.47690.86791.25991.65292.04692.44192.83793.234
60149.38150.43151.77153.38155.31157.54159.95162.47165.17168.01
70223.7226.9230.4234.1238.0242.1246.3250.6255.0259.6
80335.1340.7346.9353.5360.6368.2376.3384.9394.0403.7
90525.76527.76529.77531.78533.80535.82537.86539.9541.95544.0
91546.05548.11550.18552.26554.35556.44558.53560.64562.75564.87
92566.99569.12571.26573.4575.55577.71579.87582.04584.22586.41
93588.6590.8593.0595.21597.43599.66601.89604.13606.38608.64
94610.90613.17615.44617.72620.01622.31624.61626.92629.24631.57
95633.90636.24638.59640.94643.3645.67648.05650.43652.82655.22
96657.62660.03662.45664.88667.31669.75672.2674.66677.12679.69
97682.7684.85687.04689.04692.05694.57697.1699.63702.17704.71
98707.27709.83712.4714.98717.56720.15722.75725.36727.98730.61
99733.24735.88738.53741.18743.85746.52749.20751.89754.58757.29
100760.0762.72765.45768.19770.93773.68776.44779.22782.0784.78
101787.57790.37793.18796.0798.82801.66804.5807.35810.21813.08

Pressure Unit Converter

to

Pressure unit Conversion Table

FROM/TO
Pa
Torr
atm
mbar
psi
kg/cm
mmAq
Pascal(N/㎡)
1
7.5 X 10
9.87 X 10
10
1.45 X 10
1.02 X 105
0.10197
Torr(mmHg)
13
1
1.316 X 10
1.333
1.934 X 10
1.359 X 10
13.59
atm(atmosphere)
1.013 X 10
760
1
1.013 X 10
14.695
1.033
10332
mbar(millibar)
100
0.75
9.87 X 10
1
1.45 X 10
1.02 X 10
10.197
psi(lb/
6.89 X 10
51.71
6.8 X 102
6.89
1
7.031 X 10
703.1
kg/cm
9.81 X 10
7.536 X 102
0.968
9.81 X 10
14.223
1
10000
mmAq(水柱)
9.806
0.0736
9.68 X 10
0.098
1.42 X 10
1 X 10
1