1. The ultimate pressure of the vacuum pump
The unit of the ultimate pressure of the pump is Pa. It means that the pump is equipped with a standard test cover at the inlet and works according to the specified conditions. It works normally without introducing gas. Under working conditions, the lowest pressure tends to be stable.
2. Pumping rate of vacuum pump
The pumping rate unit is m3/s or l/s, which means that the pump is equipped with a standard test cover and works according to the specified conditions. When, the ratio of the gas flow rate flowing through the test cover to the equilibrium pressure measured at the specified position of the test cover. Referred to as the pumping speed.
3. The air pumping volume of the vacuum pump
The unit of the air pumping volume of the vacuum pump is Pam3/s or Pal/s. It refers to the gas flow rate at the pump inlet.
4. Starting pressure of the vacuum pump
The starting pressure unit of the vacuum pump is Pa, which refers to the pressure when the pump starts without damage and has a pumping effect.
5. The front-stage pressure of the vacuum pump
The unit of the front-stage pressure of the vacuum pump is Pa, which refers to the outlet pressure of the vacuum pump whose exhaust pressure is lower than one atmosphere.
6. The maximum front-stage pressure of the vacuum pump
The maximum front-stage pressure unit at the vacuum pump port is Pa, which refers to the front-stage pressure that exceeds the pressure that can cause damage to the pump.
7. Maximum working pressure of vacuum pump
The unit of maximum working pressure of vacuum pump is Pa, which refers to the inlet pressure corresponding to the maximum pumping volume. Under this pressure, the pump can operate continuously without deterioration or damage.
8. Compression ratio of vacuum pump
The compression ratio refers to the ratio of the outlet pressure of the pump to the inlet pressure of a given gas.
9. Ho's coefficient of the vacuum pump
The ratio of the actual pumping speed on the pumping channel area to the theoretical pumping speed calculated based on molecular effusion.
10. Pumping speed coefficient of vacuum pump
The ratio of the actual pumping speed of the pump to the theoretical pumping speed calculated based on molecular effusion at the pump inlet.
11. Backflow rate of vacuum pump
The unit of backflow rate of vacuum pump is g/cm2.s. It refers to the mass flow of pump flow per unit area through the pump inlet when the pump operates under specified conditions.
12. Water vapor allowance
The unit of water vapor allowance is kg/h. It refers to the amount of water the gas ballast pump can pump under normal environmental conditions when the gas ballast pump is working continuously. except the water vapor mass flow rate.
13. Maximum allowable water vapor inlet pressure
The maximum allowable water vapor inlet pressure unit is Pa. It refers to the highest inlet pressure of water vapor that can be removed by a gas ballast pump during continuous operation under normal environmental conditions.
Extended information
According to the working principle of vacuum pumps, vacuum pumps can basically be divided into two types, namely variable volume vacuum pumps and momentum transfer pumps.
A variable volume vacuum pump is a vacuum pump that uses periodic changes in the volume of the pump chamber to complete suction and exhaust to achieve the purpose of pumping air. The gas is compressed before exiting the pump chamber. ?
The momentum transfer pump relies on high-speed rotating blades or high-speed jets to transfer momentum to the gas or gas molecules, so that the gas can be continuously transferred from the inlet to the outlet of the pump.
Variable volume vacuum pumps are divided into: reciprocating type, rotary type (rotary vane type, slide valve type, liquid ring type, Roots type, spiral type, claw rotor type), and other types.
Baidu Encyclopedia-Vacuum Pump