Air Compressor Sizing

Air Flow Through OrificesVolume of free air in CFM that will flow thru round holes from a receiver into the atmosphere. Cubic feet of air per minute measured at absolute pressure of 14.7 lbs. per sq. in. and 70¼ F. Air Flow Through Orifices Dia. of Orifice (In.) Guage Pressure in Reciever - Pounds 2 5 10 15 20 25 30 35 40 45 50 60 70 80 90 100 125 150 1/64 0.04 0.062 0.077 0.105 0.123 0.14 0.158 0.176 0.194 0.211 0.29 0.267 0.3 0.335 0.37 0.406 0.494 0.583 1/32 0.158 0.248 0.311 0.42 0.491 0.562 0.633 0.703 0.774 0.845 0.916 1.06 1.2 1.34 1.48 1.62 1.98 2.32 3/64 0.356 0.568 0.712 0.944 1.1 1.26 1.42 1.58 1.75 1.91 2.06 2.38 2.7 3 3.33 3.66 4.44 5.25 1/16 0.633 0.993 1.24 1.68 1.96 2.25 2.53 2.81 3.1 3.38 3.66 4.23 4.79 5.36 5.92 6.49 7.9 9.1 3/32 1.43 2.23 2.8 3.78 4.41 5.05 5.69 6.31 7 7.63 8.25 9.5 10.8 12 13.3 14.6 17.8 20.9 7.86 37.3 1/8 2.53 3.97 4.98 6.72 8.98 10.1 11.3 12.4 13.5 14.7 16.9 19.2 21.4 23.7 26 31.6 3/16 5.7 8.93 11.2 15.2 17.65 20.2 22.8 25.2 28 30.5 33 38 43.2 48.3 53.2 58.5 71 84 1/4 10.1 15.9 19.9 26.9 31.4 35.9 40.5 45 49.6 54.1 58.6 67.6 76.7 85.7 94.8 104 126 149.3 3/8 22.8 35.7 44.7 60.5 70.7 80.9 91.1 101 112 122 132 152 173 193 213 234 284 336 1/2 40..5 63.5 79.6 108 126 144 162 180 198 216 235 271 307 343 379 415 506 596 5/8 63.03 99.3 124.5 168 196 225 253 281 310 338 366 423 479 536 592 649 790 932 3/4 91.2 143 179.2 242 283 323 365 405 446 487 528 609 690 771 853 934 1138 1340 7/8 124 195 244.2 329 385 440 496 551 607 662 718 828 939 1050 1161 1272 1549 1825 1 162 254 318.2 430 503 575 648 720 793 865 938 1082 1227 1371 1516 1661 2023 2385 1 - 1/8 205 321 402.5 544 637 727 820 910 1004 1094 1187 1370 1552 1734 1918 2101 2560 3020 1 - 1/4 253 397 498 672 784 900 1019 1124 1240 1352 1464 1693 1917 2144 2370 2596 3160 3725 1 - 3/8 307 482 604 816 954 1091 1230 1367 1505 1643 1780 2054 2330 2607 2880 3153 3840 4525 1-1/2 364 572 716 968 1132 1293 1460 1620 1783 1946 2112 2335 2760 3081 3412 3734 4550 5360 1 - 3/4 496 780 972 1318 1540 1760 1985 2205 2429 2650 2875 3310 3755 4200 4645 5085 6195 7300 2 648 1015 1274 1720 2120 2300 2594 2880 3173 3460 3752 4330 4915 5480 6070 6650 8100 9540 Table is based on 100% coefficient of flow. For well rounded entrance, multiply values by 0.97. For sharp edge orifices, a multiplier of 0.65 may be used. This table will give approximate results only. The formula Q=14.5 PD2, where Q is CFM, P is absolute pressure and D is orifice diameter in inches, may be used for any points not given in table. (Applies only above 15 pounds gauge.) Compressed Air Requirements Tool/Equipment Size or Type Air Pressure (PSI) Air Consumed (CFM) (pounds per sq.000lb cap 70-90 10 Bus or Truck Lift 8.000lb 70-90 5 cf/ft. Cleaning 70-100 9 Fender Hammer 70-90 20 70-90 18 Filing/ Sawing Machine File & Burr Tools Small 90-100 3 Filing/ Sawing Machine Large 90-100 5 70-90 3 Grease Gun Hi Pressure 120-150 4 Grinders W" Wheel 70-90 50 Grinders Z" Wheel 70-90 20 Grinders .) Air Bushing Small or Large Air Filter Cleaner 80-90 15-25 70-100 3 Light to Heavy 70-90 4.000lb cap 70-90 6 Car Lift 70-90 6 Car Rocker 70-100 3 Carbon Remover 70-90 10.0-15. 70-90 30 Backfill Tamper 70-100 7 Bead Breaker 125-150 12 Blow Gun 70-90 3 70-100 2 70-100 5 Body Polisher Body Sander Orbital Brake Tester 70-100 4 Burring Tool Small 70-100 4 Burring Tool Large 70-100 6 Burring Tool 14. of free air per min.000lb And larger up to 70-90 15 cf/ ft.0-15. lift Angle Nut Setters 5/16" weighing 8 lbs.Horizontal 6" to 8" wheel 70-90 50 Grease Gun .lift Air Hoist 2. 1/2" 70-90 20 Angle Nut Setters to 3/4" weighing 8 lbs.) (cu. Rotary 70-100 3 Dusting Blow Gun 70-90 5 Engine.0 Carving Tools Carving Tools Monumental 70-100 7 Chain Saw Lightweight 70-100 22 Chain Saw Heavy Duty 70-90 28-30 Chipping Hammers Weighing 2-4 lbs 70-90 39 Chipping Hammers Heavier than 13 lbs 70-90 30 Chipping Hammers Weighing 10-13 lbs 70-90 12 Concrete Vibrators 70-100 4 Die Grinder 70-100 7 Drill 70-90 50-110 Drills.000lb to 10. in. Piston 70-90 20-90 Drills.000 lb and under 70-90 1 cf/ft.0 70-90 10. lift Air Hammer Air Hoist 10. ft.0-40 Air Hoist 1. 0 Nut Setters & Runners Nailers and Staplers 1/4" cap to 3/4" cap 70-90 6-30. Piston Type Capacity 7/8"-1-1/4" weighing 25-30 lbs. Rotary Motors Capacity 1-1/4" weighing 30 lbs. 70-90 45 Steel Drills.0-7. Rotary Motors Capacity up to 1/4" weighing 1 1/2-4 lbs. 70-90 75-80 Steel Drills.0 Paint Sprayers Protection gun 40-70 20 Paint Sprayers Small Hand 70-90 2. 2 to 6 screw 70-90 5 Screwdrivers Nbr. 70-90 18-20 Steel Drills.Horizontal 2"-2 1/2" wheels 70-90 14-20 Grinders . 70-90 35 Riveting Hammer 70-100 8 Rotary Sanders 70-90 30 90 6-400 Riveters Sand Blasting (Blasting Data Pg J-17) Wide Variation 70-90 25-40 Sand Rammers and Tampers Sand Hammer 1" x 4" cylinders 70-90 25 Sand Rammers and Tampers 1-1/4" x 5" cylinders 70-90 28 Sand Rammers and Tampers 1-1/2" x 6" cylinders 70-90 39 70-100 3 Scaling Hammer Screwdrivers Nbr. Rotary Motors Capacity 7/8"-1" weighing 25 lbs. 70-90 95 . 70-90 80-90 Steel Drills. Rotary Motors Capacity 1/2"-3/4" weighing 9-14 lbs.Vertical Small 70-90 22 Hoist 1 ton 70-100 1 125-150 6 Hydraulic Floor Jack Hydraulic Lift 145-175 6 Small to Large 70-90 4-10. Piston Type Capacity 1-1/4"-2" weighing 40-50 lbs.Horizontal 1-1/2" wheels and under 70-90 10 Grinders and Sanders .Vertical Large 70-90 53 Grinders and Sanders . Piston Type Spring Oiler Capacity 1/2"-3/4" 13-15 lbs.Vertical Medium 70-90 30 Grinders and Sanders . Piston Type Capacity 2"-3" weighing 55-75 lbs.0 Plug Drills 70-90 40-50 Pneumatic Door 40-90 2 Pneumatic Garage Door 120-50 3 Radiator Tester 90-100 1 Rammers Small 70-100 4 Rammers Medium 70-100 9 Rammers Large 70-100 10 100-120 6 Rim Stripper Rivet Buster 70-90 35-39 Small-Large 70-90 Oct-35 Riveters 3/32"-1" rivets 70-90 12 Riveters Larger weighing 18-22 lbs. 6 to 5/16" screw 70-90 10 Spark Plug Cleaner Reach 36-45 70-90 5 Spray Gun Engine Cleaner 90-100 5 Spring Oiler 40-70 4 90-100 4 Steel Drills. Rotary Motors Capacity 1/4"-3/8" weighing 6-8 lbs.0-8.Grinders . 70-90 70 Steel Drills.0 Impact Wrenches to-1/2" 70-90 5 Impact Wrenches 1/2" to 3/4" 70-90 10 Impact Wrenches 3/4" to 1 1/4" 70-90 20 Impact Wrenches 1-1/4" to 2" 70-90 30 Impact Wrenches 2" to 3" 70-90 55 Impact Wrenches 3" to 12" 70-90 100 40-70 1 Impact Wrench/ Screw Driver Laboratory Outlet/ Station 70-100 5. 70-90 100-110 Steel Drills. 70-90 20-40 Steel Drills. 70-90 80 Steel Drills. At 50 foot head 70-90 70 Tapper to 3/8" 70-100 5 Tire Changer 70-90 1 Tire Changer 125-150 2 Tire Hammer 90-100 12 Tire Inflater 70-90 2 Tire Inflation Line 125-150 2 Tire Rim Stripper 125-150 6 Tire Spreader 70-90 1 Tire Spreader 125-150 2 Touch Up Paint Spray Gun 90-100 4 Transmission/ Differential Flusher 70-100 3 Undercoat Paint Spray Gun 90-100 19 Vacuum Cleaner Shop 100-120 6 Valve Grinder 70-90 2 Vertical Disc Sander 90-100 10 1"-2" 70-90 40-80 Wood Borers 1" diameter weighing 4 lbs 70-90 40 Wood Borers 2" diameter weighing 26 lbs.Sump Pumps 145 gals. At other than 100 PSI. count each pipe fitting as equal to 5 feet of pipe. When measuring piping distances. 70-90 80 Wood Borers Air Line Pipe Size Figures in body of chart are pipe sizes on a 100 PSI air system to carry air at about a 1 PSI per 100 feet pressure loss. to be conservative. SCFM Length of Run .Feet . flow capacity will be in inverse proportion to pressure (as based on PSIA (absolute) pressure levels and calculated by Boyle's Law). 31/2 1/2 4 Valve Sizing Valve Sizing With Cv = 1 Table This method can be used if the required air flow is known or has been calculated with the formulas as shown below: .11/4 1/2 1/2 2 2 2 300 11/2 2 2 360 11/2 2 2 450 2 2 2 600 2 2.1.2.21/2 1/2 2 2 2 2 2 2 2-1/2 21/2 2-1/2 2.2.21/2 1/2 1/2 750 2 2.21/2 1/2 1/2 3 3 2.1.1.1.1.21/2 1/2 3 3 2.11/4 1/4 1/4 1/2 1/2 2 2 180 1.1.1.1.1.1.11/4 1/4 1-1/4 1.1.1.11/4 1/4 1/4 1/2 1/2 1/2 2 1 3/4 3 3 3 3-1/2 3 3 3 31/2 4 3 3 3.1.1.21/2 1/2 3 2.11/4 1/4 1/4 1/2 1-1/2 1.11/4 1/2 1/2 1/2 2 2 2 240 1.11/4 1/4 1/4 1/4 1/2 1/2 150 1.Flow 25 50 75 100 150 200 300 500 1000 6 1/2 1/2 1/2 1/2 1/2 1/2 1/2 3/4 18 1/2 1/2 1/2 3/4 3/4 3/4 3/4 30 3/4 3/4 3/4 3/4 1 1 45 3/4 3/4 1 1 60 3/4 1 90 1 1 120 1 1 1 1 1 1 11/4 1-1/4 1.1.1.21/2 1/2 3 1 1. 8 47.0 A valve with a Cv of minimum 2 should be selected.5 140 16.9 110 15 23. Example 4: Find Cv if cylinder size and stroke speed is known.9 15.5 48.7 28.4 70 12.2 29.9 11.6 24.8 65.3 128.4 20.3 52.8 35.8 16.2 49.9 31.7 50.Air Flow Q (SCFM) for Cv = 1 Inlet Air Flow Q Pressure (PSIG) Example 2: Find Cv if air flow Q (SCFM) is given.3 150 17.3 56 90 180 18.9 12 30 9 13.8 29.8 x 21.1 48.2 160 17.8 50 10.6 23.7 30.7 120 15.6 130 16.4 34.4 46.1 41.4 99.9 22.5 60 11.7 26.8 Flow through valve from Table 28 for Cv = 1:21.4 220 20.6 210 20.8 40.7 57.7 29. since some manufacturers do not show the standard Cv to allow a comparison.4 46.1 52.5 41.5 119.9 124 250 21.6 44.3 19.1 90 13.8 37.9 21.3 230 21 33.6 44.2 54. Example 3: Find Cv if air flow Q (SCFM) to atmosphere is given.8 = 39.1 32.6 38.5 109.2 80 13 20.4 39.5 80.8 43.8 54.1 46. Primary Pressure P1 = 90 PSIG Air Flow to atmosphere Q = 100 SCFM Flow to atmosphere through valve from Table 28 for Cv = 1:51 SCFM Cv = Air Flow to atmosphere Q (SCFM) Air Flow to Atmosphere at Cv = 1 (SCFM) Cv = 100 51 Example 1: Find an air flow Q(SCFM) if Cv is known.4 60.3 85. This conversion is often necessary to size a valve properly.8 70.3 36.6 31.8 42.8 35.1 39.1 170 18.7 31.6 47.6 18.8 190 19.3 65.9 43.1 59.3 59.7 28.2 SCFM Flow given is equivalent to valve with Cv = 2.7 200 19.7 37.8 49.9 34.8 26. Cv = 1.2 51 100 14.6 37.2 24.8 SCFM Q = Cv of valve x air flow at Cv = 1 (SCFM) Q = 1.9 104.7 75.4 45.6 Flow through valve from Table 28 for Cv = 1:30 SCFM Cv = Air Flow Q (SCFM) Air Flow at Cv = 1 (SCFM) Cv = 60 SCFM 30 = 2.2 30.2 27.4 22.3 56.6 66.5 33.8 62.3 58.6 35.5 26.8 26. (SCFM) To 2 PSID 5 PSID 10 PSID 15 PSID 20 PSID Atmosphere 10 6.2 31.2 240 21.8 18.1 25.7 60.7 21. using .3 40.4 33.7 94.7 46.5 55.9 33.8 68.1 44.7 20 7.2 40 9.2 53.1 42 50.8 30 35.9 16.2 32.3 57.1 64 114. . x 10" Stroke Time to complete stroke 2 sec. Primary Pressure = 90 PSIG Pressure Drop across valve = 5 PSID Cylinder Size 4" Diam.formulas 1 and 3. Depending on the the size of the system. The water vapor content at 100¼ F of saturated compressed air is about two gallons per hour for each 100 CFM of compressor capacity.10 Amps per HP 230V .5 Amps per HP 230V . A 50 horsepower compressor rejects approximately 126. Water-Cooled Aftercoolers: 1. 400 660 1060 1600 220 2560 Dimensions 36" x 96" 42" x 117" 48" x 144" 54" x 170" 60" x 190" 60" x 220" 2.50 Amps per HP 460V .1. Size air receiver tanks for about 1 gallon capacity for each CFM of rotary compressor capacity. Every 20¼ F temperature drop in saturated compressed air at constant pressure. 2. Most water-cooled aftercoolers will require about 3 GPM per 100 CFM of compressed air at Discharge Air Tempera.000 BTU per hour for heat recovery. Air compressors are normally rated to deliver 4 to 5 CFM per horsepower at 100 PSIG discharge pressure. Compressor Discharge Temperature (Before Aftercooling): 1.13368 Water Content: 1.2. Standard receiver tank sizes are listed below: Gal. 2. compressed air costs about 25 to 42 cents per thousand cubic feet of free air ingested by the compressor (including operating and maintenance costs).Handy Rules Of Thumb For Estimating Air Compressors: 1. 4. Approximate discharge temperatures (before aftercooling) at 80¼ F ambient: PRESSURE 100 PSIG 150 PSIG 200 PSIG . 50% of the water vapor condenses to liquid. Motor amperage draw: 1 Phase 3 Phase 115V .ture at 100 psig. Cubic Feet: Gallons x 0. 3.25 Amps per HP Air Receivers: 1. 30 60 80 120 200 240 Dimensions 16" x 38" 20" x 48" 20" x 63" 24" x 68" 30" x 72" 30" x 84" Gal. 7 10. Allow Temp. (T1) = 80F (1. 10¢/ KWH Electric Power Rate = $806/ Year for 1 HP/3 shift Constant Run. (1.1 20 22 55 43 56 65 95 170 285 480 138. KW = HP x 0.6 88.) Air Required CFM = 12. 3. 4.6 4 9.060 Max.3 51. Rise Air Reciever Capacity Chart Capacity Ratings of Air Receivers In CFM for Constant Speed Operation Gauge Air Receiver Size and Volume In Cubic Feet 12 x 36 14 x 46 PSI 2 15 12 20 25 Pressure 6x 38 18 x 72 20 x 48 20 x 63 20 x 72 24 x 72 30 x 84 36 x 96 42 x 120 48 x 144 54 x 168 60 x 192 66 x 216 3. Ventilation Required The following formula will estimate the required ventilation air in cfm to adequately control ambient heat rejection from an air compressor Ð BE SURE TO USE FULL ABSORBED HORSEPOWER! EXAMPLE: WHEN TOTAL BHP = 110 CFM = 110 HP x 2546 Start Temp.T2)Temp.8 210 294 404.60 CFM = (Sensible Heat BTU/ Hr.966 CFM Vent.08)(T1 . Every 2 psig change in pressure equals 1% change in horsepower. (T2) = 100F 21.200 615 365 190 .1 17.4 1060 1560 220 14 24 27 66 52 68 78 114 204 342 3000 576 1270 1872 2640 15 28 31 77 61 80 91 133 238 400 3600 672 1480 2185 3080 4200 .215 Horsepower & Power Cost: 1. Most AIR MOTORS require 30 CFM at 90 psig per horsepower.08)(20¼)Temp. At 100 psig every 20¼ F increase in saturated air temperature doubles the amount of moisture in the air.2 31.Single-Stage Two-Stage Rotary (Oil-Cooled) 510 325 180 . Rise = 280.2 17. 2.7 7.205 --395 200 .7457 Saturated Compressed Air 1. 0025 0.0045 0.0028 0.0035 50 0.0021 0.0058 0.001 0.0018 0. Gallons Per Hour Per CFM Percentage Of Saturation Temp º F 40 50 60 70 80 90 100 35 0.0017 0.0041 0.0017 0.0014 0.0024 0.0025 0.0054 0.0015 0.0032 0.0042 0.0035 0.003 0.0048 0.0042 0.002 0.0024 40 0.0063 0.0021 0.0021 0.0012 0.0049 0.0066 0.0036 0.0012 0.0075 0.0035 0.0022 0.0042 55 0.007 70 0.003 0.0026 0.0056 0.0017 0.0029 45 0.004 0.0083 .0034 0.0024 0.0025 0.0038 0.003 0.30 18 32 36 88 69 91 104 152 272 456 768 1692 2500 3520 4800 35 20 37 41 100 78 102 117 170 306 513 865 1905 2810 3960 5400 40-125 24 41 46 110 87 114 130 190 340 570 960 2115 3120 4400 6000 126-350 36 57 63 165 122 160 182 285 510 855 1440 3172 4680 660 9000 351-500 48 82 91 220 174 228 260 380 680 1140 1920 4230 6240 880 12000 501-620 60 102 113 275 217 285 325 475 850 1425 2400 5288 7800 11000 15000 621-720 72 121 134 330 261 343 390 570 1020 1710 2880 6346 9360 13200 18000 721-800 84 144 160 385 305 400 455 665 1190 1995 3360 7404 10920 15400 21000 801-880 96 164 182 440 348 457 520 760 1360 2280 3840 8462 12480 17600 24000 881-950 108 184 204 495 391 513 585 855 1530 2565 4320 9520 14040 19800 27000 951-1000 120 205 228 550 435 571 650 950 1700 2850 4800 10578 15600 22000 30000 Determine the Water Volume The following chart was created to simplify the procedure necessary to determine the amount of water vapor that is present in a cubic foot of air at various temperature and humidity conditions.003 0.7 PSIA). and 35¼ pressure dew point.005 60 0.0015 0.006 65 0.002 0.005 0. The design conditions are based on sea level (14.0028 0. 0185 0.0057 0.0236 110 0. Take the CFM rating of the air compressor system that you intend to dehydrate.0186 0.0144 0. please round up to the next number present. determine your maximum temperature and humidity condition.0049 0.0271 115 0.) Locate the factor that is at the intersection point of these two conditions.016 0.0095 0.0283 0.0088 0.0163 0.0138 0.0097 80 0.0114 85 0.0217 0. The answer you get is the total amount of water in gallons per hour that would be condensed when chilled to 35¼ F .0118 0.0155 0.0078 0.0093 0. Multiply the CFM by the factor at the intersection of the proper conditions.0166 0.0177 0.0132 90 0.0154 95 0.0102 0.0123 0.0108 0.0142 0.0071 0.0045 0.008 0.0123 0.0142 0.0213 0.0205 105 0.0119 0.0068 0.0103 0.0106 0.0189 0.0079 0.0066 0.0039 0.0125 0.0136 0.0279 0.0077 0.0212 0.0319 0.0248 0.0061 0.0178 100 0.019 0.0092 0.031 120 0.0217 0.0107 0.0164 0.0354 To use this chart.0091 0.0089 0.0068 0. (In the event you are between ratings.0124 0.75 0.0058 0.0108 0.0053 0.0244 0.0142 0.0082 0.0248 0.