In petroleum and chemical production, some production processes are often carried out under atmospheric pressure. The pressure below atmospheric pressure is called vacuum, and vacuum degree is often used to indicate the degree below atmospheric pressure. Vacuum pump is used in the petroleum industry for vacuum distillation, lubricating oil denitrification, furfural recovery, etc., and in the chemical industry for vacuum filtration, evaporation concentration, drying, crystallization, etc. Vacuum pump can also be used as a large-scale centrifugal pump, such as water filling pump.
Mechanical vacuum pump can be divided into reciprocating, rotary (sliding plate type) and water ring type according to its structure.
Generally, any vacuum pump uses the following two main parameters to express its working performance
(1) air extraction rate refers to the volume of gas drawn in from the intake pipe by the vacuum pump under the residual pressure in unit time, i.e. the production capacity (or current V) of the vacuum pump, expressed in m3 or L / s.
(2) residual pressure or ultimate vacuum refers to the minimum pressure (absolute) that the pump can reach.
No matter how long the suction time is, the pressure in the container cannot be reduced to zero (absolute vacuum) indefinitely. This is because when the air inlet pressure is lower than a certain value, or because the liquid in the pump vaporizes, or because the air disk leaked from the high pressure side is the same as the suction of the vacuum pump, or because the compression ratio of the vacuum pump is too high, the volume coefficient is reduced to zero, which will make the pump unable to continue to inhale new fresh gas. In this case, the pressure in the container will never decrease again. The absolute pressure is called residual pressure or ultimate vacuum.
Vacuum Pump In Pharmaceutical Industry
DLV Series Double Stages Water Ring Vacuum Pumps
2SK Liquid Ring Vacuum Pump
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