Answer: In the current micro pump selection type, such as miniature vacuum pumps, micro -gas pumps, micro gas sampling pumps, micro gas circulating pumps, micro -pump pumps, micro -absorbing pumps, micro pumps, miniature pumps, micro -pressure air pumps, etc., often need It involves these three concepts.

First, it is simple to say that these three concepts correspond to the thin, normal, and dense state of the gas.

Normal pressure: refers to a atmospheric pressure, that is, the gas pressure generated by this atmosphere of our usual life. A standard atmospheric pressure is 101325 PA (Pascal-Pasca-Commonly used pressure unit). 100,000Pa = 100kPa, so "a standard atmospheric pressure" we also often use 100kPa or 101kPa. Due to the geographical location, altitude height, temperature, etc. in each place, the actual local atmospheric pressure is not equal to the standard atmospheric pressure, but for the purpose of simplifying, sometimes it can be approximate that the normal pressure is a standard atmospheric pressure, that is, 100kPa;

Negative pressure: It refers to the gas state of low air pressure than normal pressure, which is the "vacuum" we often say. For example, when drinking drinks with a tube, the tube is negative pressure; the inside of the suction cups used to hang things is also negative pressure.

Positive pressure: refers to the gas state of high pressure than normal pressure. For example, when giving bicycles or tires, the outlet of the air pocket or air pump is positive pressure.

2. In many fields such as scientific research, biological engineering, automatic control, environmental protection, water treatment, etc., gas sampling, gas circulation, and object adsorption are often used. At this time, vacuum pumps must be used. Its main parameters include real vacuum, traffic, and so on.

(1), "Quality" generally refers to the extreme pressure that can be achieved when the pump works, that is, after the gas in the closed container can be pulled away, the remaining gas is thinner.

In industrial, extreme pressure indicates that there can be two types, one is "absolute pressure", that is, "absolute vacuum" (absolute vacuum that can be achieved theoretically, no matter) is zero, and the marked values are all. At the same time, the smaller the number, the closer to the absolute vacuum, that is, the higher the vacuum. For example, we have a "high vacuum" miniature vacuum pump VCH1028. Its extreme pressure is 10kPa (0.01MPa), and in the micro vacuum pump, it belongs to the high vacuum.

The other is "relative pressure", that is, the atmospheric pressure is used as zero, and the negative value is lower than the atmospheric pressure, so it is called "negative pressure". The greater the absolute value of this negative value, the higher the vacuum. For example, if we have a "high negative pressure miniature vacuum pump" PH2506B negative pressure is -75kPa (-0.075MPa), there is no VCH1028 high (VCH is -90kPa (-0.09MPa)). Therefore, the corresponding pH2506b's suction power is not strong.

The international vacuum industry is universal and the most scientific is the "absolute pressure" logo; but because the method of measurement is simple and the measuring instruments are common (such as the general vacuum table is a relatively stressometer), the domestic habit uses "relative pressure to stressful pressure "Come to identify.