A, if you just use the micro air pump output compressed air.
Simply put, it is only used to pump and inflate, the pumping port of the pump is basically not used. This situation is relatively simple, according to the output pressure from large to small in order to choose: PCF5015N, FAA8006, FAA6003, FAA4002, FM2002, FM1001, of course, but also refer to the flow indicators and other relevant technical parameters.
Two, if the micro-pump pumping, the situation is slightly more complex, roughly from the following two aspects to determine the selection:
1. Judgment of the micro-pump pumping end of the working conditions
Used for pumping micro-pumps are divided into two categories: gas sampling pumps and micro-vacuum pumps. Although it is usually always indiscriminate to them simply referred to as a miniature vacuum pump, but from a technical point of view of the two are different, the selection of special attention.
In short, the gas sampling pump can only take a small load (i.e.: the pumping end of the pumping resistance can not be too large), but the price is cheap; the strict sense of the micro-vacuum pump can take a large load (the pumping end of the pumping end to allow a large resistance, or even completely blocked), but the price is slightly more expensive. Specific differences between the two can be detailed in the article "on the difference between miniature vacuum pumps and gas sampling pumps", will not be repeated.
Gas sampling pumps: SA, SB, PM series (eg: SA751.5, SB550.5, PM950.2, etc.);
Micro vacuum pumps: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH series, PH series, VBH series, FM series, FAA series, PCF series, all the sizes under these series are true miniature vacuum pumps, such as VM7002, VAA6005, PC3025 and so on.
The size of the resistance at the pumping end of the miniature pump can be measured with an instrument, and it can be compared with the Por value of the pump's technical parameter "Maximum Resistance at the Inlet" to know whether the selection is appropriate or not. Usually based on experience using simple methods to determine, for example, the following cases are loaded (i.e., the pumping end of the pump resistance), can only be selected within the scope of miniature vacuum pumps:
① in the pumping end of the pump to be connected to the very long pipeline, or the pipeline bending points, bending even blocking the closed, or the pipeline is very small hole (for example, less than ?2 millimeters);
② in the pipeline There are throttle valves, solenoid valves, air switches, filters and other components;
3 pump pumping port connected to a closed container, or the container is not closed but the air intake is small;
4 pump pumping port connected to the suction cup for adsorption of objects (such as integrated blocks, precision workpieces, etc.);
5 pump pumping end is connected to the filtering container, the container mouth placed on the strainer, used to accelerate the liquid filtration
5) The pump's pumping end is connected to the filtering vessel, and a screen is placed at the mouth of the vessel to accelerate liquid filtration.
2. Judgment of micro-pump exhaust end conditions
The above are discussing the micro-pump pumping end resistance, according to these judgment conditions have narrowed down the scope of selection, but must also consider the exhaust end resistance, so as to finalize the optional range.
In practical applications, miniature vacuum pumps face different exhaust conditions: a class of exhaust is very smooth, straight through the atmosphere; the other class is the exhaust resistance is larger, such as in the exhaust pipeline valves, fine bends, large damping sensors, non-specialized silencers, in the liquid level below the exhaust, gas discharge to the confined or semi-closed containers and so on. In modern design and manufacturing, micro vacuum pumps facing different exhaust conditions are treated differently. The parameter "maximum permissible resistance Por value at the exhaust port" is what calibrates the pump's exhaust capacity and allows us to determine the appropriateness of the selection using strictly technical means.
Simply put, for systems with high exhaust resistance, our selection range is: FM series, FAA series, PCF series; for systems with low exhaust resistance, the selection range is: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH series, PH series, VBH series.
Based on the above steps, we have been able to determine the selection range of miniature pumps. In the delineation of a few optional series, and then according to our requirements for flow and vacuum can determine the specific model.
Note that the parameter selection should leave a margin, especially the flow parameters. After the pump is connected to the gas system, due to piping, valves and other gas components to cause pressure loss, will attenuate the flow rate, so the flow rate obtained is less than the nominal flow rate of the pump.
Three, there are a number of issues related to selection are listed below, according to the use of consideration.
1, with load start problem.
If the miniature air pump before the start of its pumping port there has been a vacuum or exhaust port there has been a pressure, it is necessary to consider another technical parameter of the pump: the maximum starting load Pis value of the intake port, the maximum starting load Pos value of the exhaust port. Typical application examples are the use of miniature air pumps to maintain vacuum or positive pressure inside the container, when the vacuum or positive pressure inside the container is lower than the set value, the pump needs to be energized to start, higher than the set value of the shutdown.
Products that can be started at the ultimate vacuum level they can achieve include: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH series, PH series, and VBH series.
Products that can be started at the maximum output pressure they can achieve are: FM series, FAA series, PCF series.
This performance requires a high level of technology from the manufacturer.
2, miniature pump medium temperature problem.
Based on the temperature of the medium gas through the pump, choose whether you want ordinary type or high temperature type.
3, miniature pump reliability.
Based on the severity of the consequences of the failure of the miniature pump, depending on their own requirements. The average trouble-free continuous operation time of high-quality products are greater than 1,000 hours, some as high as thousands of hours. Special attention is paid to this parameter is measured under full load, uninterrupted operation, the worst working conditions, if the actual use is not full load or continuous operation, the value will be higher, how much higher depending on the working conditions of the pump. The performance is entirely a test of the manufacturer's technical strength, from the appearance of the product can be seen, such as the use of special motors rather than ordinary low-priced motors, the volume of the case of the same heavier weight, etc.. According to the price of the product can also be a little known.
4, micro-pump electromagnetic interference.
If there is a precision circuit to control the miniature pump, depending on the circuit's ability to resist interference, you may need to order a low electromagnetic interference miniature pump.
"Chengdu Xinwei Cheng Technology Co.