The main advantage of Roots vacuum pump is that it can operate with high pumping
speed under lower suction pressures, however, has to be backed by a backing pump.
(See Fig.3) Under normal working conditions, it is permissible to not add by-pass pipes.
Roots vacuum pump should not operate with a higher-pressure difference than allowable,
otherwise overheating and overload will cause damage of Roots vacuum pump.
Therefore, proper backing pump and necessary protection devices must be considered.
|Extract Capacity (L/S)||30||70||150||300||600||1200|
|Inlet diameter (mm)||50||80||100||150||150||300|
|Outlet diameter (mm)||40||50||100||150||150||300|
1. Ultimate pressure (Pa) value is measured by mercury McLeod vacuum gauge.
2. Pumping speed refers to maximum pumping speed measured when Roots vacuum
pump is connected with a recommended backing pump with an inlet pressure ranging
from 67Pa to 2. 7Pa.
3. Ultimate pressure refers to lowest value of stable partial pressure measured at inlet
port of a Roots pump without any additional vessels after sufficient suction with inlet
of it tightly closed by a blank flange when connected with a recommended backing
4. Each performance above the list is obtained under recommended backing pump.
Customers can select backing pump suitable for the intended application, but its main
performance index may have some changes.