－20－
5.2
Pumping speed
The pumping speed of the pump depends on the type and pressure of the gas to be evacuated.
The pumping speed usually reaches the maximum at a high pressure range, and it gradually
decreases as the pressure reduces.
The nominal pumping speed of this pump is the maximum pumping speed when dry air is
evacuated. Figure6 shows the relationship between the evacuation pressure and pumping
speed.
Figure6. Pumping speed curve
