ft. of free Air per minute at atmospheric Pressure of 14.7 psia, and 70 °F. The table given below gives the discharge of air through an orifice in cu. Don’t forget your compressed air fittings! CFM of compressed air required to raise a known system pressure to a desired system pressure:C2 = Required CFM total C1 = Existing or known CFM P2 = Desired pressure P1 = Known Pressure EXAMPLE: A 75 HP Compressor rated at 320 CFM t 125 PSIG will hold only 85 PSI and we desire 125 PSI.C1 = 320 CFM P2 = 125 + 14.7 (139.7) P1 = 85 + 14.7 (99.7) Finally, you’ll need to conduct an operating analysis, which allows you to find the optimal level of compressed air you should produce. From global corporations to intelligent trades businesses; from food production to aerospace: Our customers benefit day in, day out, from the quality, safety, and cost efficiency that a Kaeser compressed air supply brings. Pressure drop is caused by friction of the compressed air flowing against the inside of the pipe and through valves, tees, elbows and other components that make up a complete compressed air piping system. Multiply psig by 6.9 to obtain KPa 2. Then how can I find pressure drop from this leak. To keep it simple my system consists of a 5.5 bar supply (550000Pa) supply on 12mm OD Nylon Tubing and is reduced to 6mm OD Nylon through a valve (pressure drop assumed neglible for now) so the valve is treated as a simple orifice. I'm trying to ascertain the dynamics of a compressed air system in terms of flow rate, air consumption, pressure drop etc. Pressure drop is caused by friction of the compressed air flowing against the inside of the pipe and through valves, tees, elbows and other components that make up a complete compressed air pipe system. In our compressed air system in a leakage test it found that there is a leak of 4.375 m3/minute. For air line 2 1/4″ and up assume a 3% pressure drop per 100′ of air line and you should be safe; Air Fittings Affect Flow And Increase Pressure Drop. – Note the time it takes for the receiver pressure to drop and for the compressor to turn on or load up. The chart was calculated from a formula published by the Fluid Controls Institute, Inc., 12 Bank St., Summit, NJ 07901, which, when simplified for a Cv of 1.00, compressed air (specific gravity of 1.00), and an air temperature of 80 to 100°F, reads as follows: Q is the air flow in SCFM P1 is the inlet pressure, PSIG P2 is the outlet pressure, PSIG ft. air gage pressure (acfm) in PSIG 1 To find the free air equivalent for 100 acfm of compressed air refer to the vertical line at 100 psi, go up to the diagonal, then horizontal to the left, to find the multiplier of 8. Then, 100 8 = 800 scfm 1. Pressure drop in a compressed air system is a critical factor. For sharp-edged orifices a multiplier of 0.65 may be used. Multiply scfm by 0.5 to obtain nl/s Online pressure drop in compressed air pipework calculator from the KAESER Toolbox of online calculators. For well-rounded entrance multiply values by 0.97. Customer Success Stories. Typically, an inlet filter causes air pressure to drop when air is pulled through, and compressor vendors need to account for this to accurately estimate performance. Pressure losses in pipework calculations made easy. With this information, average system compressed air demand can be calculated with the following equation: C = V(P(sub 1) – P(sub 2))/tP(sub 0) Where: C = air demand, cfm of free air Based on 100% coefficient of flow. Customer Success Stories. – Repeat these steps over a reasonable period of time. Pressure drop in a compressed air system is a critical factor. From global corporations to intelligent trades businesses; from food production to aerospace: Our customers benefit day in, day out, from the quality, safety, and cost efficiency that a Kaeser compressed air supply brings. I would like to know about compressed air pressure drop calculation from air leak. 1cu. Every elbow, every Tee and even every coupling cause turbulence in the air as it passes, and this increases the pressure loss. Discharge of Air Through An Orifice Equation.