Weak current College】 【air filter parameters --- Power By】 【China power house network.

<br> 1. rated air flow RatedAirflow <br> <br> In unit time filter through a certain volume of gas flow, internal general use m3 / h air flow units abroad also used Imperial air units cfm (cubicfootperminute), ft3/mim .cubic feet per minute, both conversion: 1cfm ≈ 1.7m3 / h. Of course we want to filter in the same wind section, you can pass the air better, said its filter capacity, but mainly by its filter material and structure. <br .> <br> 2. surface speed sufacevelocity and filtration speed filtervelocity <br> <br> Speed means wind section on airflow speed, m / s in General to represent; <br> <br> Surface speed = air volume ÷ upwind area < .br> <br> Filtering speed means the filter material on airflow speed, generally expressed in cm / s; <br> <br> Filtering speed = air volume ÷ filtration area <br> <br> Filtration area means the filter material in the .area, only when the filter material for Planar direction normal to the airflow, the filter of the wind section and filtration area is the same, but in the vacuum cleaner filter often discount forming. <br> <br> Abroad also used Imperial wind speed .units: fpm (footperminute) <br> <br> Feet / minute, 1000fpm ≈ 5.08m / s <br> <br> 3. filtration efficiency Efficiency <br> <br> 1), definitions: filtration efficiency = filter and trap .to the amount of dust in the upper air dust ÷ = (upper air dust-downstream air dust) ÷ upstream of the dust content of the air <br> <br> Efficiency definition seems simple, but its meaning and value and test methods are .closely related, different testing methods to get the value of efficiency is not directly comparable, so speak to efficiency must indicate what is the efficiency of the test method. Abroad is also sometimes used transmittance Penetration or penetration to represent filtration performance, through rate = 1 .-filtration efficiency <br> <br> 2) specifications: <br> <br> A, China specifications: primary efficiency (Course) effect (Medium) high efficiency (HighMedium)-high-efficiency (SubHEPA) (HEPA) <br .> B, European specifications: GFHU grade 4 <br> <br>.