Technical Resource Center
Calculation
Technical Resource Center
Calculation
Calculation
When inlet mass flow constant
Formula(1) : V = W x 22.4/Mw x (273+T)/273 x 760/P
| Where) | V : Exhaust Velocity of Vacuum Pump(㎥/hr) T : Suction temperature(℃) Mw : Moleculat Weight(Kg) W : Suction Flow Rate(Kg/Hr) P : Suction Pressure(Torr) |
|---|---|
| Example(1) | Suction Temperature : 60℃ Suction Temperature : 15 Torr Suction Flow rate : 10Kg/Hr(Air) |
| Then | Vair = 10 × 22.4/29 × (273 + 60)/273 × 760/15= 478㎥/hr |
When evacuation volume constant
Formula(2) : S=V/T x 2.3 log P1/P2
| Where) | S : Exhaust Velocity of Vacuum Pump(㎥/hr) V : Equipment Volume (㎥) T : Evacuation Time P1 : Initial Pressure(torr) P2 : Final Pressure(torr) |
|---|---|
| Example(1) | Equipment Volume : 20㎥ Evacuation Time : 30 Min. Final Pressure : 5 Torr |
| Then | S = 20 /0.5 × 2.303Log 760/5 = 201 ㎥/hr |