College】 【weak air filter selected the voice of experience.

<br> experience shows that, for the same structure, the same filter media, when the end of the resistance OK: media area increased by 50%, the filter will extend the service life of 70% to 80%; double filter .life is about 3 times the original. .Multi-media, filters, prices will increase accordingly, but certainly not as good as the level of increase the magnitude of the filter life expectancy. .Furthermore, the effective area is large, the initial resistance decrease, the system's energy consumption will fall. .For users, the effective area of a large selection of certain cost-effective filter. .<BR> <BR>, Of course, the filter according to the specific structure and site conditions to consider the possibility of increasing the effective filtration area. .Such as bag filter, filter bag can increase the number and length of the bag; traditional clapboard filters to reduce the partition with the manufacturers of the interval to increase the number of pleated filter paper; for the design of the project, you can choose .can accommodate more than the kind of filter material filter. .<BR> <BR> HEPA filter must be tested by Taiwan <BR> <BR> abroad, the manufacturer of high efficiency filter-by-station testing is self-evident thing. .Within the very particular about the factory on the production line just under the high efficiency filter testing, can pick out a 3% filter tainted point, most of which can be restored to the qualified, but there are still about 1% of which are beyond repair .scrapped. .<BR> <BR> Manufacturers in the country, just off the assembly line of high efficiency filter testing, the failure rate of 3% to 10%, in extreme cases, the failure rate of up to 30%. .Sadly, hundreds of domestic high efficiency filter manufacturer, has less than 10% of the means test, which can be tested by Taiwan manufacturers insist it is one of the few. .A large number of untested high efficiency filter into the market, and many users are not prosecuted. .Visual inspection can not find the leak point of the filter. .For the high-purity occasions, a leak in the filter is enough to make the whole project fails. .Therefore, every high efficiency filters in the factory, must be conducted in a special test stand standard performance test. .Once selected by Taiwan tested without the high efficiency filter, the user must bear the risk of project failure. .<BR> <BR> Between the filter manufacturers may use a different testing method, the user may be in favor of or suspect a specific method. .The most basic principle is that each manufacturer must have high efficiency filter for routine testing, and specific test methods can be further discussed. .<BR> <BR> Most manufacturers of high efficiency filter holding third-party inspection report or certificate of authenticity. .These documents represent the performance of the sample submission, does not guarantee that your purchase is approved filter pass. .In many cases, third-party merchants report presented to the people the more people the more we doubt whether he really means test, if true to the high efficiency filter-by-station testing. .<BR> <BR> Country has a strange phenomenon for a long time many manufacturers and scientific research departments continue to develop high efficiency filter, but few people to worry about tests, so that thing with the results for a large, decent product .are rare. .Until 2001, there are still people to re-develop the so-called "0.1mm high efficiency filter." .Developed for many years, today's generous clean domestic project, its high efficiency filter is still a small number of foreign manufacturers monopoly. .<BR> <BR> Current, high efficiency filter for many domestic manufacturers, the establishment of testing methods, and insisted on testing by Taiwan, which is to change the reputation of high efficiency filter made of the most urgent task is to enhance the product competitive in the most direct .means, but also manufacturers the most likely thing done. .<BR> <BR> Adhere to the by-station testing will increase production costs (cost of testing, waste), the price will increase slightly, as long as you can prove that each high efficiency filter are tested, the user will trust your product. .Comparison of fiber diameter, coarse filtration <BR> <BR> identified in the filtration process, the fiber is to intercept the dust of the obstacles. .Fiber thin, the number of fibers per unit volume to more; fiber and more, filtration efficiency is high. .Energy flow around the fiber Movement, the performance of air flow resistance for the fiber. .Two filtration efficiency of the same material, crude fiber resistance, fine fiber resistance. .In addition to being fiber blocking dust, but also can be blocked early capture of dust, so dust the surface of fiber to "dendritic structure" loosely stacked, fiber is the "dry", dust is the "sticks." .Fiber and more, to the formation of branched structures are more dust per unit area can accommodate the more, the long filter life. .Fiber and more space between the fibers when the small, branched structure formed by the dust on the solid dust blown off the possibility of secondary pollution caused to small. .<BR> <BR> The same thickness, the same bulkiness of the two media, fine fiber media filter, high efficiency, fine fiber filter dust holding capacity. .The same efficiency, the same structure, consisting of two different fibers from the filter, fine fiber media resistance is low. .<BR> <BR> Air-conditioning system itself needs a good filter <BR> <BR> Over the years, air-conditioning designers to the needs of users select a filter, and now, people realize, too, must have a good central air conditioning filter .to protect. .<BR> <BR> Only low efficiency filters, air-conditioningsystem problems and more: airway obstruction, air scaling, the air volume decreases; reduce the efficiency of heat transfer components; temperature and humidity measurement and control component failures; dynamic end of the air supply .equipment failure; total heat exchange device failure; pipe fouling moderate temperature and humidity is an ideal place for microorganisms to propagate. .<BR> <BR> Number of central air conditioners, the use of one or two years, the performance degradation, open the air conditioner, the crux of a glance. .The phenomenon: fouling; its roots: the low efficiency filters. .<BR> <BR> In developed countries, the use efficiency of the filter specifications for the F5 (the assay 45%, in Europe the old standard EU5, China Specifications "in effect"), central air conditioning system every 5 to 8 years to be cleaned once .; with F7 filter efficiency (45%, EU5, high efficiency) of the central air conditioner, used after 30 years without cleaning. .Our existing comfort air conditioning, the filter often as "coarse," and some did not even filter section, used a few years later, the unsightly within the system. .<BR> <BR> Performance degradation due to fouling caused by air-conditioning is far greater than the economic losses caused by the cost of using the best filter; shortened life expectancy due to fouling the air conditioner caused economic loss is greater than the cost of using the best filter; .cleaning costs (you will find air conditioning needs cleaning) will also higher than the cost of using the best filter. .<BR> <BR> In developed countries, the cost of cleaning air conditioning system is good or bad filter post 20 times. .Air-conditioning system temporary lack of domestic cleaning company, a number of years, users will find clean air to how expensive. .<BR> <BR> Good air-conditioning system, the filter efficiency specifications shall not be less than F6 ~ F7. .<BR> <BR> <BR> <BR> Owners suffer a domestic-star hotels, central air-conditioning design, no filter section. .Building before delivery, delivery outlet has a black stain, the owners asked people inside the temporary addition of the air conditioner "in effect" filter segment. .Hotel opening more than a year after the sharp drop in air-conditioning system, open the air conditioner a look, cooling clogging, fouling pipes, fans scaling. .Air-conditioning system owners determined to reform and transform the money spent times in the first built, the cost of using the best filter. .<BR> <BR> <BR> <BR> Hapless Paris, a contractor built 90 office buildings, using the dynamic end of the supply air unit with air-conditioning system. .Contractor to install a low-efficiency air conditioner filters, resulting in savings of 20 million francs. .Building opened a year later, many of the end of device failure. .Contractors have asked people to clean the entire air conditioning system, cleaning fees spent 600 million francs. .<BR> <BR> Points <BR> <BR> itself needs a good central air conditioning filters to protect. .Low efficiency filters will allow users and contractors to pay a high price. .F7 efficiency filters to protect air-conditioning systems for 30 years. .<BR> <BR> The impact of wind speed on the filter <BR> <BR> In most cases, wind speed, the lower the better use of filters. .The diffusion of small particle dust (Brownian motion) was significantly, low wind speed, the air in the filter material on the longer retention time, the dust will have more opportunities to hit obstacles, the filtration efficiency is high. .Experience has shown that, for the high efficiency filter, wind speed reduced by half, reduce the transmission of dust close to an order of magnitude (numerical increase in the efficiency of a 9), wind speed doubles, the transmission will increase an order of magnitude (reduced efficiency of a 9). .<BR> <BR> And diffusion effect is similar to that when the filter material with static electricity (the electret material), the retention of dust in the filter longer, be more likely adsorbed material. .Change in wind speed, the efficiency with electrostatic filter material will change significantly. .If you know the material on static electricity, air-conditioning system is designed to be as much as possible through each filter to reduce the amount of wind. .<BR> <BR> The main mechanism for the inertia of large particles of dust, according to traditional theory, the wind speed drops, dust and fiber will reduce the chance of collision, filtration efficiency will be reduced. .However, in practice this effect is not obvious, because the wind speed, the fiber on the rebound force is also small dust, and dust is more likely to be stuck. .<BR> High wind speed, the resistance to large. .If the filter's life to end the resistance, based on high wind speed, the short filter life. .Generally difficult for users to actually observe the impact of wind speed on the filtration efficiency, but the observed wind speed on the impact resistance is much easier. .<BR> <BR> For high efficiency filters, air flow rate through the filter is generally 0.01 ~ 0.04m / s, in this context, filters, air flow resistance and a positive correlation between filtration. .For example, a 484 × 484 × 220mm high-performance filters, the rated air volume 1000m3 / h under the initial resistance to 250Pa, if you use the actual air volume is 500m3 / h, its initial resistance can be reduced to 125Pa. . For the general ventilation air box filters, air flow through the filter at a rate of 0.13 ~ 1.0m / s range, resistance and air flow is no longer a linear relationship, but a rising curve, the wind increased by 30% .resistance may be increased by 50%, if you filter resistance is a very important parameter, you have to asksuppliers to filter resistance curve. .<BR> <BR> <BR> <BR> Filter does not filter function can capture any form of particles, including droplets. .Filter material soft, was porous, somewhat silencer effect. .Filter on the airflow resistance, some are current role. .<BR> <BR>, However, can not be won at any time the filter when the retaining plate, not when the muffler, nor when the wind deflector. .<BR> <BR> Filter with water, the above mixed with water to form slurry fouling. .If the filter material is a dense filter paper or filter cloth, filter mud paste will soon die. .Filter material for the more fluffy, absorbent, the group has captured the dust may vary with water droplets into the air side under the filter, then a dry, dust will be flying again. .Sometimes, the filter with water dripping Buzhi Yu serious to the extent, but enough to filter trace moisture on the windward side of dust transported to the leeward side, filters, dried, dust has to re-flying risks. .<BR> <BR> Test was done to the bag filter dust on the spray complicated, does not increase the resistance of the filter. .Resistance to change, that did not keep dust and which go? .Of course, with water running. .Where is the filth filter, wet the propagation of beneficial microorganisms, and other mold better said, encounter "Legionella" (35 ℃, humidity, air-conditioning systems), big trouble. .Filter is to deal with dust, though some sound absorption effect, but you can not use the assessment approach to investigate the muffler filter. .If the user requirements muffler or muffler honestly the use of specialized equipment, not played the filter idea. .<BR> <BR> Particular, for gas turbines and large centrifugal compressor inlet filter, replacement filter elements may be allowed when the shutdown, if no specific silencer, filter indoor work environment will be very bad, operators .operation would not care. .<BR> <BR> In addition, the filter can not be won with a wind deflector. .No filter plate so strong, in reality, there had been many failures due to wind board or design mistakes, and let the fan blowing straight filter, resulting in abnormal damage to the filter example. .Any time, any form of filters, you can not do wind carries it to boards. .<BR> <BR> <BR> <BR> Points only to deal with dust filter, it is not multi-functional duties, and no multi-functional ability. .<BR> <BR> <BR> <BR> <BR> <BR>.