Compressors / compressed air - DMK

9 Sound pressure level andsound power levelWe indicate the sound power level LWA as well as the sound pressurelevel LPA for the sound levels on our compressors. In order todemonstrate that such values are not compared to one another andcannot be compared with other noise levels, e.g. for aircrafts we giveyou a short explanation how to determine the two values below.· Sound pressure level L P A10 Determination of the compressed air requirementMost work cycles are only temporary. For these cycles, you may calculate anaverage on time (ED). Furthermore, these consumers are generally used timedisplaced.The average on-time (ED) and the factor of simultaneous f use areincluded in the requirement reducing multiplication.Overall compressed air consumption: In order to dimension your compressoryou should also take the following factors into consideration: losses due toleakages, reserves and miscalculation.The volume is defined by its proper value by the sound pressureor by the logarithmic sound pressure level. The sound pressuredescribes the actual effect of a sound source on the air pressure andthus on the human hearing. It is directly measured and is alwaysdepending on the distance to the sound source and on the acousticalconditions in the room. The sound pressure level is the value whichis used to determine the occupational safety and health protection(Occupational health and safety regulations).· Sound power level L w AThe sound power determines the sound energy emitted by a soundsource for each time unit. It can be determined by measuring thesound pressure at several places on an enclosed enveloping surfacearound the sound source. This value is not directly measured butcalculated and does not depend on the distance or on the acousticsof the room. The sound power level for instance servesto define legal limit values when using devices outdoors (Outdoordirective).Calculation example:Compressed air Working Duty cycle Number Individual A x q x ED/100consumption pressure ED (%) A (pcs.) consumption(bar)q (l/min.)Color spray gun 3 40 1 180 72ø 1.5 mmBlow out gun 6 10 3 65 19.5ø 1.0 mmImpact screw-driver 6 20 3 200 120M 10Drilling maschine 6 30 1 700 210up to ø 20 mmAngle grinder 6 40 2 500 400Sum Q of the compressed air consumption of the consumers (l/min.) 821.5Factor of simultaneous use f 0.71Compressed air consumption of the consumers Qf = f x Q (l/min.) 583.313