When using low throughputs and searching for leaks commonly the volume throughput qpV in pV-Units for stating the leakrate is used. Moreover the type of gas and the temperature have to be considered.
- m/t mass flow (m=mass, t=time)
- v Number of moles v = m/M (m=mass, M=molar mass of the gas
- R molar gas constant (R=8,314 J*mol^-1K^-1
- T temperature
- t time
Leakrate Conversion
convert the basic leakrate units.
Leakrate Conversion
This table shows the unit conversion factors when using different volume or mass throughput units. For this conversion standard state of the gas is considered.
Unit | mbar 1/s | Pa 1/s | Torr 1/s | lusec | cm3/s | cm3/hour | kg/hour Air | g/year R12 |
|---|---|---|---|---|---|---|---|---|
Torr 1/s | 1.33 | 1.33 | 1 | 1000 | 1.32 | 4738 | 5.7E-3 | 2.1E5 |
Pa 1/s | 001 | 1 | 7.5E-3 | 7.51 | 0.99E-2 | 35.6 | 4.3E-5 | 1.55E3 |
mbar 1/s | 1 | 100 | 0.75 | 751 | 1 | 3560 | 4.3E-3 | 1.55E5 |
lusec | 1.33E-3 | 0.133 | 1E-3 | 1 | 1.32E-3 | 4.74 | 5.7E-6 | 2.1E2 |
kg/hour Air | 230 | 23000 | 175 | 1.75E5 | 230 | 8.29E5 | 1 | - |
g/year R12 | 6.4E-6 | 6.4E-4 | 4.90E-6 | 4.80E-3 | 6.4E-6 | 2.3E-2 | - | 1 |
cm3/s | 1.01 | 101 | 0.76 | 759 | 1 | 3600 | 4.3E-3 | 1.55E5 |
cm3 /hour | 2.81E-4 | 2.81E-2 | 2.11E-4 | 2.11E-1 | 2.7E-4 | 1 | 1.21E-6 | 4.30E1 |
Annotations
- Jousten, Karl (Hrsg.): Handbuch Vakuumtechnik. Vieweg+Teubner Verlag, 2006. ISBN 383480133X, 9783834801333, Seite 751[↩]