With the vigorous development of China's instrumentation industry, compact, oil-free miniature vacuum pump, micro-pump is more and more widely used. How to choose the most suitable for your product in a variety of micro-pump?
According to the use of micro-pump, can be divided into three categories to discuss:
First, if only the output of compressed air micro-pump.
Simply put, it is to use it to cheer, inflatable, pump exhaust port basically do not have. This situation is relatively simple, according to the output pressure from descending order of options: PCF5015N, FAA8006, FAA6003, FAA4002, FM2002, FM1001, of course, refer to the relevant technical parameters such as flow indicators.
Second, if it is the following situations, you should choose PHW600B or WAA series products.
1, with a mini pump or vacuum pump, but sometimes there will be liquid water into the pump chamber.
2, require micro-pump both pumping and pumping.
3. Pumping mainly with micro pumps, but do not want to manually add "water diversion" before pumping (some pumps need to manually add some "water diversion" before work, so that the pump can pump low water up, otherwise the pump can not pump water or even pump Damaged.), I hope the pump has "self-absorption" function. The beauty of the PHW600B or WAA series is that when it is not in contact with water, it is evacuated, pumped up by air pressure after a vacuum is formed and then pumped.
4, using micro-pump pumping, but sometimes there may be no pump pump water, in a "dry turn" state. Some traditional pumps fear "dry turn", "dry turn" can even damage the pump. The PHW600B or WAA series is essentially a compound function pump that integrates the functions of a vacuum pump and a pump, some call it a "vacuum pump." So, in the absence of water, it will be evacuated, and when it has water it will pump it. Whether it is pumping or pumping state, belong to the normal work category, it does not matter "dry turn" damage.
Third, if it is to pump with a micro-pump, the situation is slightly more complicated, roughly from the following two aspects to determine the selection:
(A), to determine the micro pump pumping end condition
Miniature pumps for pumping are divided into two categories: gas sampling pumps and miniature vacuum pumps. Although they are often referred to as miniature vacuum pumps simply and indiscriminately, they differ from the technical point of view and require special attention.
In short, the gas sampling pump can only be used with a small load (ie, the pump suction resistance must not be too high), but the price is very low; in the strict sense of the micro-vacuum pump can carry a large load Blocked), but the price is slightly expensive. Specific differences between the two can be found in my company's Web site "test data" in the article "on the difference between micro-vacuum pump and gas sampling pump," will not repeat.
Gas sampling pumps are: PM series (specific models such as: PM950.2, PM850.5, PM8001, PM7002, PM6503); miniature vacuum pumps are: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH Series, PH series, FM series, FAA series, PCF series, all the specifications under these series are real miniature vacuum pump, such as VM7002, VAA6005, PC3025 and so on.
For the mini pump, the resistance of the suction side can be determined by the instrument and compared with the technical data of the pump "Por of maximum allowable air inlet resistance" (definition of "inlet Por" can be found in VM series detailed parameters) Selection is appropriate. Usually based on experience and easy to use methods to determine, such as the following several cases belong to a larger load (ie pump suction end of the resistance), can only be selected within the miniature vacuum pump range:
In pump suction end to take a long pipe, or pipe bending point, bending or blocking, or the hole is very small (such as less than ∮ 2 mm);
In the pipeline throttle, solenoid valve, gas switch, filters and other components;
Pump suction port and airtight container connection, or the container is not closed but the intake is smaller;
Pump suction port and sucker connection, for the adsorption of objects (such as manifolds, precision workpieces, etc.);
The pumping end of the pump is connected to the filter container, which is used to speed up the liquid filtration.
(B), to determine the micro pump exhaust conditions
The above discussion is about the mini pump pump end resistance, according to these judgment conditions have narrowed the selection range, but also must consider the exhaust end resistance, so as to finally determine the optional range.
In practical applications, micro-vacuum pump facing the exhaust situation is not the same:
One is the exhaust is smooth, straight through the atmosphere;
The other is a larger exhaust resistance, such as in the exhaust pipe valve, a small bend, a large damping sensor, non-specific muffler, exhaust below the liquid level, gas discharged to airtight or semi-airtight containers. In the modern design and manufacturing, to face the different exhaust conditions of miniature vacuum pump treated differently. "The maximum allowable Por value of the exhaust port" (see definition of the "exhaust port Por" for details on the VM series parameters) This parameter is used to calibrate the exhaust capacity of the pump, so that we can use strict technical means to determine the appropriate selection.
In short, for the system with large exhaust resistance, our selection range is: FM series, FAA series, PCF series; For the system with small exhaust resistance, the selection range is: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH series, PH series.
Based on the above steps, we have been able to determine the selection of micro-pump range. In the delineation of a few optional series, and then based on our flow and vacuum requirements can determine the specific model.
Note that the parameters to choose to leave a margin, especially the flow parameters. Pump connected to the gas system, due to the pipeline, valves and other airway components to cause pressure loss, will reduce the flow, the resulting flow is less than the nominal pump flow.
The following are other issues related to the selection, please consider the use of:
1, with the load start problem.
If the miniature pump already had a vacuum on its suction port or the pressure in the vent already exists before starting the miniature pump, consider another pump specification: Pis for the maximum start of the air intake and Pos for the largest start of the exhaust The definition of these two values, see the VM series detailed parameters). A typical application example is the use of micro-air pump to maintain the container under vacuum or positive pressure, when the vacuum or positive pressure within the container is lower than the set value, the need for pump power start, higher than the set value shutdown.
Products that can be activated under the limit of vacuum that can be achieved by itself are: VM series, VAA series, PK series, PC series, VCA series, VCC series, VCH series, PH series;
Products that can be activated under the maximum output pressure that they can achieve are: FM series, FAA series, PCF series.
The performance of the manufacturer's technical requirements.
2, micro-pump medium temperature problems.
Depending on the temperature of the medium gas passing through the pump, the choice is either ordinary or high temperature.
3, the reliability of micro-pump.
Depending on the severity of the consequences of the mini pump failure, it is entirely based on your own requirements. The average quality of trouble-free continuous operation of more than 1,000 hours, some up to thousands of hours. Special attention to this parameter is measured at full load, continuous operation, is the worst operating conditions, if the actual use is not full or continuous operation, the value will be higher, depending on the number of high pump conditions set. The performance is a test of the manufacturer's technical strength entirely, from the product appearance can be seen some, such as the use of special motors instead of ordinary low-cost motor, the case of considerable weight and other heavy. According to product prices can also know a little bit.
4, micro-pump electromagnetic interference problems.
If you have a precision circuit-controlled micropump that depends on the circuit's immunity to interference, you may want to order a miniature pump with low electromagnetic interference.