Vacuum pump pressure calculation formula of _

the function of the vacuum pump gas molecules are removed from the vacuum chamber and reduce the gas pressure in the vacuum chamber in order to achieve the required vacuum. Usually, from atmospheric pressure to high vacuum range is very wide, so far there are no vacuum system to cover the scope. Therefore, in order to achieve different product craft standard, working efficiency and working life of the equipment requirements, different vacuum part need to choose a different vacuum system configuration. For optimal configuration, when choosing vacuum system should consider the following:

first of all, you must check to make sure the vacuum degree necessary for the each process. Because each process has its own vacuum level range, so must study carefully. Determining critical vacuum

on the basis of determine the processes needed for the vacuum check limit vacuum in the vacuum pump system, because of the limit of the vacuum system determines the best job in the vacuum system. In general, the limit of the system vacuum 20% lower than the system of vacuum, 50% lower than the previous level limit vacuum.

to pumping gas type and pumpage

check the water pump type and determine the quantity of pumping required for the process. Because if the pumping of the type of gas and liquid in the pump to reaction, the pump system will be contaminated. At the same time, must be considered to determine proper exhaust time and pumping process of gas volume.

amount of vacuum check the time needed for the desired vacuum, flow resistance and vacuum pipeline leakage. After considering the desired vacuum, under a certain technological requirements of required to keep the vacuum pumping rate.

the main vacuum pump selection calculation of

S = 2. 303V/tLog( P1/P2)

:

S for the vacuum pump suction rate ( L/s)

V for vacuum chamber volume ( L）

t to reach for the vacuum degree required by the time ( s)

P1 for initial vacuum degree, Torr)

P2 for vacuum degree ( Torr)

for example:

V = 500 l

t = 30 S

P1 = 760 torr

P2 = 50 torr

is: S = 2. 303V/t Log( P1/P2)

= 2。 303x500/30xLog( 760/50)

= 35。 4 l/s

of course on the theoretical calculation results, there are a number of variable factors not taken into account, such as pipe flow resistance, leakage, flow resistance of the filter, is pumped gas temperature, etc. In fact should also take into consideration of the factor of safety. In the industrial application is one of the most water ring vacuum pump and rotary vane vacuum pump for general requirement is:

1, vacuum, vacuum volume, main medium, temperature, volume devices.

2, vacuum flow and flow rate, pressure, temperature, medium are studied.

3, swept volume, spare gas medium and temperature.

4, covers an area of vacuum equipment, automation degree, vacuum pipe specification