DETERMINING YOUR AIR REQUIREMENTS GENERAL TERMS CONTINUED CHECKING EXISTING COMPRESSOR CAPACITY NOTES:

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3 GENERAL TERMS CONTINUED PISTON DISPLACEMENT: Is the volume swept by the piston, generally expressed in cubic feet per minute (CFM). For multi-stage compressors, the piston displacement of the first stage only is commonly stated as that of the entire machine. ACTUAL CAPACITY: Is the quantity of gas actually compressed and delivered to the discharge system by the compressor at rated speed and under rated pressure conditions. Actual capacity is expressed in cubic feet per minute at the temperature and pressure conditions existing at the inlet to the first stage. VOLUMETRIC EFFICIENCY: Is the ratio of actual capacity to piston displacement, generally stated as percentage. FREE AIR: Generally describes air at room or ambient temperatures and pressures, that is, normal atmospheric conditions. In other words, the term free air describes the air actually taken into the suction of a compressor which takes air from the surrounding atmosphere. STANDARD CONDITIONS: Are not universally defined; therefore, since compressor capacities are sometimes expressed in standard cubic feet per minute (SCFM), it is necessary to identify, before the compressor can be sized, () the standard pressure condition; (2) the standard temperature condition; (3) the compressor suction pressure condition, and; (4) the compressor suction temperature condition. The most popular identification for standard pressure and temperature conditions is 4.5 PSIA or 60 F. BRAKE HORSEPOWER (bhp): Is the measured horsepower input at the compressor shaft. The horsepower output of the driver must equal or exceed the compressor bhp plus any drive losses. LOAD FACTOR: Is the ratio of the available demand for compressed air during a certain period of time to the maximum rated output capacity of the compressor. NOTES: DETERMINING YOUR AIR REQUIREMENTS A relatively simple procedure to see if additional compressor capacity (CFM) is required can be performed in any plant or compressed air-using operation. Most general compressor air operations supply 00 PSIG at the compressor and deliver a minimum of 90 PSIG to the using air tool. For lowest possible power cost, this means compressor has a cut out pressure or unloads at 00 PSIG and cut-in or loads at 90 PSIG receiver or system pressure. With these known figures (or whatever unload and load figures a particular system utilizes), we can determine the following: If the receiver is below the normal cut-in point (90 PSIG) or does not gradually rise to the cut-out point (00 PSIG), more air is probably needed. Always check, of course, that there are no significant leaks and that the unloading and control system on the compressor are functioning correctly. NOTE: If the compressor must operate at more than 00 PSIG to get 90 PSIG at the tools, check the distribution system for piping size or check points. The pipe may be too small or a single choke point too small for the system s total demand (flow) or length. CHECKING EXISTING COMPRESSOR CAPACITY Running a timed pump-up test is a relatively accurate way to check your existing air compressor s capacity or output. This will confirm that your shortage of compressed air is not due to a worn unit or a malfunction. Check the receiver volume in cubic feet. Check the pipe volume between the compressor and receiver in cubic feet. Operate the compressor at load. Close the air valve between the receiver and plant air system. Drain the receiver down to 70 PSIG. Close the drain valve quickly. Record in seconds the required time to pump to 00 PSIG. Now work the following equation: If this is close to the rated capacity of your air compressor, then you can be relatively sure the demand on your air system is too high and you need additional air. C = COMPRESSOR CAPACITY IN CFM V = RECEIVER & PIPING VOLUME IN CU. FT. P2 = FINAL CUT OUT PRESSURE PSIA = 00 PSIG = 4.7 PSIA P = INITIAL PRESSURE PSIA = 70 PSIG = 84.7 PSIA V (P2 - P) 60 SEC. C = (4.7) (TIME-SEC.) * Assume the receiver and piping volume were 80 cu. ft. * Assume the pump-up time is 5 seconds. Then solve: C = C = (80) ( ) (60) (4.7) (5) 44, C = 653 cubic ft./min. = actual capacity of existing air compressor 28

4 TERMINOLOGY CONTINUED UNLOAD (No Load): Air compressor continues to run (usually at FULL RPM), but NO air is delivered because intake is either closed off or modified, NOT allowing inlet air to be trapped. MODULATING UNLOAD: Air compressor continues to run and air supply is matched to demand by partial unloading. This is usually accomplished by a regulator controlled floating inlet. START-STOP CONTROL: Air supply is matched to demand by actual starting and stopping of the unit. CUT-IN/CUT-OUT PRESSURE: The settings on a pressure switch used to either load or unload the air compressor on constant speed application. The cut-out pressure is also referred to as maximum pressure, the point at which there is NO AIR DELIVERED. The cut-in pressure is also referred as minimum pressure - the pressure that the system is allowed to fall to before additional air volume is called for. The compressor runs at full load between cut-in and cut-out. VARIABLE DISPLACEMENT CONTROLS: Also called Rotor Length Adjustment in oil cooled Rotary Screw controls. Particularly efficient in holding constant speed from 60% to 00% capacity variable speed control. Below this usually goes to blow down and idle. VARIABLE SPEED CONTROL: Most commonly applied in oil cooled Rotary Screws. Very efficient from about 50% to 00% capacity. Below 50% usually defaults to modulation of Blow Down and idle. RATED PRESSURE: The operating pressure at which the air compressor s performance (CFM and BHP - Horsepower required) is measured. SPECIFIC POWER: Used to compare air compressor efficiency unless otherwise stated. Usually in form of BHP/00 ACFM or CFM/HP. GENERAL TERMS COMPRESSORS: Are machines which compress air or gases from atmospheric pressure to a higher discharge pressure. BOOSTER COMPRESSORS: Are machines which compress air or gases from a pressure higher than atmospheric to a still higher discharge pressure. VACUUM PUMPS: Are machines designed for compressing air or gases from an initial pressure which is below atmospheric to a pressure which is at or close to atmospheric pressure. RECIPROCATING COMPRESSORS: Are positive displacement machines used to increase the pressure of a definite volume of gas by volume reduction. The compressing element is a simple piston which reciprocates back and forth in a cylinder. COMMON LEAK PROBLEM AREAS COUPLINGS, HOSES, TUBES AND FITTINGS Tubes and push-to-lock fittings are common problems. DISCONNECTS O-rings required to complete the seal may be missing. FILTERS, REGULATORS AND LUBRICATORS (FRL s) Low first-cost improperly installed FRL s often leak. OPEN CONDENSATE TRAPS Improperly operating solenoids and dirty seals are often problem areas. PIPE JOINTS Missed welds are a common problem. CONTROL AND SHUT-OFF VALVES Worn packing through the stem can cause leaks. POINT OF USE DEVICES Old or poorly maintained tools can have internal leaks. FLANGES Missed welds are a common problem. CYLINDER ROD PACKING Worn packing materials can cause leaks. THREAD SEALANTS Incorrect and/or improperly applied thread sealants cause leaks. HOW DO YOU FIND LEAKS? Since air leaks are almost impossible to see, other methods must be used to locate them. The best way to detect leaks is to use an ultrasonic acoustic detector, which can recognize the high frequency hissing sounds associated with air leaks. These portable units consist of directional microphones, amplifiers, and audio filters, and usually have either visual indicators or earphones to detect leaks. A simpler method is to apply soapy water with a paint brush to suspect areas. Although reliable, this method can be time consuming. Other methods include: smoke sticks, candles, foam, manometers and stethoscopes. Ultrasonic detectors can find mid to large sized leaks. The advantages of ultrasonic leak detection include: versatility, speed, ease of use, the ability to perform tests while equipment is running and the ability to find a wide variety of leaks. HOLE DIA. AIR LEAKAGE AT 00 PSI COST PER YEAR IN. CFM $.06 KWH /32.62 $58 /6 6.5 $633 /8 26 $2,532 /4 04 $0,30 WHAT DO SYSTEM LEAKS COST? Determine size of leak either through calculation or actual size of orifice. /4 inch orifice can pass PSIG. A typical 25 horsepower oil flooded Rotary Screw Air Compressor. At 6 cents a kw and 8,000 hours of operation, this can equal $9,

5 USEFUL FORMULAS. COMP. RPM = 2. MOTOR PULLEY p.d. = 3. COMP. PULLEY p.d. = comp. pulley p.d. x comp. RPM 4. MOTOR RPM = motor pulley p.d. 5. FREE AIR = piston displacement x volumetric eff. (%) 6. REQUIRED PISTON free air = DISPLACEMENT vol. eff. motor pulley p.d. x motor RPM comp. pulley p.d. comp. pulley p.d. x comp. RPM motor RPM motor pulley p.d. x motor RPM comp. RPM 7. PISTON DISPLACE- Cyl. bore x Cyl. bore x stroke in In. x RPM = MENT IN CU.FT. MIN* CU. FT. COM- cu. ft. free air x atmospheric pressure = PRESSED AIR (PSIG + 4.7) 9. CU. FT. cu. ft. compressed air x (PSIG + 4.7) = FREE AIR atmospheric pressure 0. CU. FT. FREE AIR REQ D TO RAISE REC. FROM 0 GAUGE TO FINAL PRESSURE vol. of rec. in cu. ft. x PSIG = atmospheric pressure. CU. FT. FREE AIR REQ D TO RAISE REC. FROM SOME PRESS. vol. of rec. (final PSIG initial PSIG) = x GREATER THAN 0 in cu. ft. (atmospheric pressure) GAUGE TO A FINAL HIGHER PRESSURE 2. PISTON SPEED IN 2 x stroke (in inches) x RPM = FT. PER MIN GALLONS = cu. ft CU. FT. = gallons x TOTAL FORCE IN LBS. OF AIR = Area of Cylinder x CYLINDER Dia. in sq. inches 6. CFM OF FREE AIR REQUIRED Vol. of Cyl. Cycles (Gauge Press ) TO OPERATE = in cu. ft. x per min. x (4.7) AIR CYLINDER (SINGLE ACTING) For Double Acting Cylinders Multiply by 2. PSIG of air press. used * Piston displacement for multi-stage compressors - only the low pressure cylinder is considered. 24 * ORIFICES ARE REQUIRED ANTICIPATING YOUR FUTURE AIR REQUIREMENTS The following charts will be helpful to anyone planning a future air system or requirement. Remember, these are averages for various types of tools and you should always consult the manufacturer for exact air requirements and analyze your own operation to evaluate normal. INDUSTRIAL TOOLS & EQUIPMENT AIR AVG. FREE NORMAL PRESSURE EQUIPMENT AIR CONS. LOAD RANGE CFM FACTOR** *Dusting Gun (Blow Gun) 3.0 0% *Drill, /6 to / % *Drill, 3 /8 to 5 / % *Screwdriver, #2 to #6 Screw.0 5% *Screwdriver, #6 to 5 /6 Screw 3.0 5% *Tapper, to 3 / % *Nutsetters, to 3 / % *Nutsetters, to 3 / % *Impact Wrench, 3 /8 sq.dr % *Impact Wrench, /2 sq.dr % *Impact Wrench, 5 /8 sq.dr % *Impact Wrench, 3 /4 sq.dr % *Impact Wrench, sq.dr % *Die Grinder, Small % *Die Grinder, Medium % *Horizontal Grinder, % *Horizontal Grinder, % *Horizontal Grinder, % *Horizontal Grinder, % *Vertical Grinders & Sanders, 5 Pad % *Vertical Grinders & Sanders, 7 Pad % *Vertical Grinders & Sanders, 9 Pad % *Filing & Sowing Mach., small *Filing & Sowing Mach., large % 5% *Burring Tool, small *Burring Tool, large % 30% *Bench Rammer % *Floor Rammer % *Backfill Tamp % *Compression Riveter.0 0% *Automatic Drills % *Air Motor, HP % *Air Motor, 2 HP % *Air Motor, 3 HP % *Air Motor Hoist, 000# 5.0 0% *Air Motor Hoist, 2000# 5.0 0% *Cylinder Type Hoist.5 0% HAMMERS *Scaling Hammer % *Chipping Hammer % *Riveting Hammer % SPRAY GUNS *Point Spray Gun (Production) *Point Spray Gun (Touch-up) % 25% Always check with tool manufacturers for actual consumption of tools being used. The above are based on averages and should not be considered accurate for any particular make of tools. The free air consumptions listed herein are based on the use of the normal load factors shown in the adjacent column. Load factor is a percentage that expresses the normal actual usage of air as compared to the maximum usage that will occur if the tool s throttle valve is turned fully open and the tool is operated continuously at maximum capacity (Load factors should be adjusted based on your own individual operating conditions). 5

6 THREE PHASE MOTOR DATA - For 60 Hz 800 RPM Standard Motor MOTOR /2 3 /4 / / MOTOR SYSTEM 200V (208V) /0 3/0 4/ / MOTOR SYSTEM 230V (240V) /0 3/ /0 2-4/ FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS HOSE SIZE FRICTION OF AIR IN HOSE GAUGE CU. FT. OF AIR PER MINUTE AT 80 PSIG PRESSURE OF LINE LOSS OF PRESSURE (PSI) IN 50 FT. LENGTHS OF HOSE / / These devices are to be considered as continuously operating devices when operating normally. All other devices listed are to be considered as intermittently operated when operating normally. When the devices consist of a large number of the continuously operated type, and if only a few are to be used at one time, the compressor should have a capacity at least equal to the total consumption of all those tools used simultaneously, in addition to the consumption of all the intermittently operated tools, if any. **Normal load factor is the percentage of time the throttle valve is open during normal use. TANK DIMENSION COMPRESSED AIR RECEIVER CAPACITY CAPACITY IN GALLONS CAPACITY IN CU.FT. OF FREE AIR AT GAUGE PRESSURE SHOWN x x x x x x

7 FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE CONTINUED LINE PRESSURE - PSIG NOMINAL CFM PIPE SIZE FREE AIR SCHEDULE 40 DISCHARGE OF AIR THROUGH AN ORIFICE In cubic feet of free air per minute at standard atmospheric pressure of 4.7 lb. per sq. in. absolute and 70 F GAUGE PRESSURE BEFORE ORIFICE IN LBS. PER SQ.IN. DIAMETER OF ORIFICE /64 /32 /6 /8 /4 3 /8 /2 5 /8 3 /4 7 /8 Discharge in cubic feet of free air per minute Table is based on 00% coefficient of flow. For well rounded entrance, multiply values by For sharp edged orifices a multiplier of 0.6 may be used for approximate results. Values for pressures from to 5 lbs. gauge calculated by standard adiabatic formula. Values for pressures above 5 lbs. gauge calculated by approximate formula proposed by S.A. Moss. Where: W = ACp W = discharge in lbs. per sec. T A = area of orifice in sq. in. C = Coefficient of flow P = Upstream total pressure in lbs. per sq. in absolute T = Upstream temperature in F abs. Values used in calculating above table were: C =.0, p = gauge pressure lbs./sq. in. T = 530 F abs. Weights (W) were converted to volumes using density factor of lbs./cu. ft. This is correct for dry air 4.7 lbs. per sq. in. absolute pressure and 70 F. Formula cannot be used where p is less than two times the downstream pressure. 20 9

8 FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE CONTINUED NOMINAL CFM PIPE SIZE FREE AIR 2 SCHEDULE 40 LINE PRESSURE - PSIG FRICTION OF AIR IN HOSE - Pulsating Flow* SIZE OF HOSE, GAUGE COUPLED PRESSURE EACH END, IN. AT LINE, LB. /2 3 /4 CU.FT. FREE AIR PER MIN. PASSING THROUGH 50 FT. LENGTHS OF HOSE LOSS OF PRESSURE (PSI) IN 50 FT. LENGTHS OF HOSE

9 FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE CONTINUED NOMINAL CFM PIPE SIZE FREE AIR SCHEDULE 40 LINE PRESSURE - PSIG Table. Refrigerated Air Dryer Performance ( data per PSIG) 50 F Dew-Point Unit Inlet temperature Inlet water vapor - lbs./hr Lbs. water removed/hr Water removed, percent Percent of design point Sensible load - btu./hr Latent load - btu./hr Total load - btu./hr Percent of design Operation kw./hr F Dew-Point Unit Inlet temperature Inlet water vapor - lbs./hr Lbs. water removed/hr Water removed, percent Percent of design point Sensible load - btu./hr Latent load - btu./hr Total load - btu./hr Percent of design Operation kw./hr

10 DETERMINING ADDITIONAL COMPRESSED AIR REQUIRED TO BRING YOUR AIR SYSTEM BACK TO 00 PSIG Once the actual existing compressed air capacity is known, it is relatively easy to mathematically determine the air required to bring the air system up to 00 PSIG: CFM (REQUIRED) = CFM (REQUIRED) = CFM P2 P 653 (4.7) = 884 CFM 84.7 Therefore, the total air capacity required to hold 00 PSIG is 884 CFM and the additional then is or 23 cubic feet per minute. Additional compressed air is required to meet the current demand. Depending on the type of system and type of air supply, a leakage or unload factor should be added to any requirement. This is generally from 20% to 30% depending on the condition. Using a 20% extra capacity factor, the total air requirement would then be 884 x.20 = 060 CFM and an additional ( ) 408 CFM would be recommended. ANALYZING THE COST OF SYSTEM LEAKS A shortage in capacity is often due to or certainly partially due to system leakage. Air system leaks are a continuing source of lost power and should always be minimized. A number of small leaks to that of a /4 orifice would at 00 PSIG pass CFM of compressed air. This is a 25HP air compressor to you. A.04 per KWH operating 8,000 hours per year, (3 shifts) this would cost you $6,600 in power cost to do no work. Defective tools, shut-off valves, packings, fit-ups, drain cocks, etc., should be continually checked. Most plants can always afford the maintenance labor and parts to correct leaks. Total system leakage can be identified by measuring time in seconds for the system (receiver) pressure to drop from 00 to 90 PSIG with no air supply or usage: For example, assume the total receiver and piping of the system is 20 cubic feet. If the plant has a 90 second bleed down rate is 90 PSIG when no production air is being used, this is leakage. The calculated leakage capacity is: CFM (LEAKAGE) = (20) ( ) (60) = 54 CFM (90) 4.7 TOTAL COMPRESSED AIR LEAKAGE = 54 CFM X.5 = 62 CFM * Add 5% to adjust for the higher leakage rate at the 20 PSIG to 90 PSIG (30 PSIG x.5) * Any leakage rate beyond 5% of the total system should be corrected. GENERAL TERMS CONTINUED SINGLE-ACTING COMPRESSORS: Are machines which compress on only one side of the piston. Compression takes place on only one stroke per revolution of the compressing element. DOUBLE-ACTING COMPRESSORS: Are machines which compress on both sides of the piston. The running gear consists of a crank and crosshead mechanism with the piston rod attached to the crosshead, and extending into the compressor cylinder through a packing box. Compression takes place on both strokes in each revolution. AIR RECEIVERS: Are large tanks placed in compressed air systems. A receiver acts primarily as a pulsation damper and warehouse for air. It also serves to collect condensate. Consequently, it is advisable to equip receivers with automatic moisture traps. SINGLE STAGE COMPRESSORS: Are machines which use only one step or stage to compress from the initial pressure to the final discharge pressure. MULTI-STAGE COMPRESSORS: Are machines which use more than one step or stage to compress from the initial pressure to the final discharge pressure. For example, a two stage compressor compresses in two steps; a three stage compressor compresses in three steps, etc. INTERCOOLERS: Are heat exchangers used to remove the heat of compression between stages of compression on multi-stage compressors. AFTERCOOLERS: Are heat exchangers designed to remove the heat of compression after the final stage of compression in addition to removing moisture from the compressed air. MOISTURE SEPARATORS: Are used generally in conjunction with aftercoolers and intercoolers to collect and remove the moisture which has condensed in compressed air lines. AUTOMATIC MOISTURE TRAPS: Are devices designed to automatically eject from the system the moisture collected in the separator. ABSOLUTE PRESSURE: Is the existing gauge pressure (as read on a gauge) plus atmospheric pressure. Atmospheric pressure at sea level is 4.7 PSIA; therefore, for 00 pounds gauge, the absolute pressure (PSIA) is 00 plus 4.7, or 4.7 PSIA. RATIO OF COMPRESSION: Is the absolute discharge pressure divided by the absolute suction pressure. For a compressor taking in atmospheric air at sea level and compressing it to 00 pounds gauge, the ratio of compression is 4.7/4.7 = 7.8. (Note that in compressors, ratio of compression is a ratio of pressures. It should not be confused with the similar term used by internal combustion engine manufacturers. In engines, ratio of compression is a ratio of volumes) 2 27

11 WHAT IS ELECTRIC ENERGY COST? HP x.746 x HRS. x RATE ELECTRIC ENERGY COST (DOLLARS) = MOTOR EFFICIENCY This is the formula for electric energy cost in dollars, and you can see it is a function of: The number of hours of operation The power used to drive the Compressor (HP) The power rate (cents per kw) The motor efficiency This formula is acceptable as accurate for estimating and comparison purposes. (Your actual power bill can be further affected positively or negatively by such things as Power Factor - Demand Charges, etc.). THE MAGNITUDE OF ENERGY COST (ELECTRIC)! To see the magnitude of your potential expenditure in power cost, calculate the power cost of a 00 HP Air Compressor: TERMINOLOGY CFM DISPLACEMENT: CUBIC FEET PER MINUTE measures the volume displaced by the air compressor at full RPM - but not Delivered Air or Usable Air. CFM DELIVERED CUBIC FEET PER MINUTE: Volume of air delivered to the system by the air compressor at rated pressure. ICFM: INLET CFM is rated volume of Inlet air (at Inlet conditions i.e.: temperature and pressure 4.7 PSIG at sea level) taken in to the compressor. ACFM: Is the actual cubic feet per minute of inlet compressed air delivered to the system at a specified point at the final discharge pressure. i.e.: the compressor delivers 625 ACFM of compressed air at 00 PSIG at the discharge end of the aftercooler. FOR EXAMPLE 6,000 hours a year Rate of $.07/kW Motor efficiency.90 Inlet = 700 ICFM at 4.7 PSIA, 0 PSIG Compressed to 625 ACFM at 4.7 PSIA, 00 PSIG ELECTRIC ENERGY COST = (00) (.746) (6,000) (.07).90 ELECTRIC ENERGY COST = $34,800 PER YEAR A 00 HP Air Compressor would have a $34,800 per year power cost. The initial purchase price of a 00 HP Air Compressor, lubricated, for plant air will probably range from $35,000 to $50,000 depending on the type. In short, the ELECTRIC ENERGY COST OF OPERATION in a Heavy Duty Cycle-Full Load 6,000 Hours (2 Shifts Plus)) CAN EQUAL OR EXCEED THE INITIAL COST OF THE UNIT EVERY YEAR. Perhaps we should pay attention to this often overlooked continuing cost. A POSITIVE VARIANCE OF 5% - 25% in energy cost can be a significant savings in any operation, and this is obtainable. CONVERSION FACTORS TO CONVERT FROM TO MULTIPLY BY Kilowatt Hours (kw h) Horsepower Hours (hp h).34 0 Watts (W) Horsepower (hp) TO CONVERT FROM TO DIVIDED BY Bars Pounds Force per Sq. In. (lbf/in 2 ) (PSI) SCFM: Standard Cubic Feet Per Minute is ACFM or ICFM CONVERTED to standard intake conditions - (60 F, 0% RH & 4.7 PSIG usually) for rating using equipment. To size for other than standard conditions, i.e.: altitude or hot weather corrections must be made. PSI: Pounds Per Square Inch - A rating of air pressure in the system. PSIA ABSOLUTE : Pressure. i.e.: Sea level PSIA or 0 PSIG (gauge pressure). PSIG: Gauge pressure shows amount of air pressure above ambient; i.e.: Sea level = 0 PSIG = 4.7 PSIA. CONSTANT SPEED CONTROL: Unit runs continuously but matches air supply to demand by loading or unloading the compressor. FULL LOAD: Air compressor is running at FULL RPM with Fully Open Inlet and Discharge delivering maximum volume (ACFM) at Rated Pressure (PSM). 4 25

12 AUTOMOTIVE SERVICE EQUIPMENT MOTOR SYSTEM 460V (480V) MOTOR SYSTEM 575V (600V) AIR AVG. FREE PRESSURE EQUIPMENT AIR CONS. RANGE CFM *Air Filter Cleaner *Body Polisher *Body Sander (Orbital) *Brake Tester *Carbon Remover *Carwasher Dusting Gun (Blow Gun) *Grease Gun *Panel Cutter Drill, /6 to 3/ *Impact Wrench, 3/8 sq.dr *Impact Wrench, /2 sq.dr *Impact Wrench, 5/8 sq.dr *Impact Wrench, 3/4 sq.dr *Impact Wrench, sq.dr *Die Grinder *Vertical Disc Sanders *Filing & Sawing Machine, small *Filing & Sawing Machine, large *Burring Tool Hydraulic Lift Hydraulic Floor Jack Pneumatic Garage Door Radiator Tester Spark Plug Cleaner Spark Plug Tester 0.5 HAMMERS *Air Hammer *Tire Hammer *Bead Breaker 2.0 SPRAY GUNS *Engine Cleaner *Paint Spray Gun (Production) *Paint Spray Gun (Touch-up) *Paint Spray Gun (Undercoating) Spring Oiler 4.0 TIRE TOOLS Rim Stripper Tire Changer Tire Inflation Line Tire Spreader *Vacuum Cleaner 6.5 THREE PHASE MOTOR DATA - For 60 Hz 800 RPM Standard Motor CONTINUED MOTOR /2 3 /4 / / /0 3/0 4/ /0 3/ FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS 6 23

13 BLASTING DATA APPROXIMATE AIR CONSUMPTION (CFM) PER BLAST NOZZLE MOTOR SYSTEM 5V (20V) MOTOR SYSTEM 230V (240V) NOZZLE SIZE / /6 (*3) /4 (*4) /6 (*5) /8 (*6) /6 (*7) /2 (*8) /8 (*0) /4 (*2) NOZZLE SIZE NOZZLE PRESSURE 80 PSI 90 PSI 00 PSI 20 PSI APPROXIMATE ABRASIVE CONSUMPTION (LBS./HR.) PER BLAST NOZZLE NOZZLE PRESSURE 80 PSI 90 PSI 00 PSI 20 PSI / /6 (*3) /4 (*4) /6 (*5) /8 (*6) /6 (*7) /2 (*8) /8 (*0) /4 (*2) Air volume and pressure are very important. The blasting production rate will increase with higher blasting pressures and decrease with lower blasting pressures. The National Association of Corrosion Engineers data suggests that.5% of production is lost for each PSI reduction in blast nozzle pressure. Pressure drop through the blast unit itself is normally less than PSI. Air pressure loss can be avoided by using the shortest possible hose of adequate size. SINGLE PHASE MOTOR DATA (60 Hz) MOTOR /6 /4 /3 /2 3 /4 / / FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS FULL LOAD CURRENT (NEC) - AMPS MINIMUM COPPER WIRE SIZE - (75 C) THW, THHN- THWN, XHHW - SIZE CIRCUIT BREAKER Thermal-Magnetic Breaker Trip Rating - AMPS FUSIBLE SWITCH With Dual Element Time Delay Fuse - AMPS 8 2

14 LOSS OF AIR PRESSURE DUE TO FRICTION - IN PSI 00 FT. OF PIPE OR HOSE 00 PSI GAUGE INITIAL PRESSURE CU. FT. FREE AIR EQUIVALENT CU. FT. COMPRESSED TYPICAL Nominal Diameter, In. (I.D.) PER MIN. AIR/MIN. /2 3 /4 /4 /2 2 2 /2 3 3 / For longer or shorter lengths of pipe or hose, the friction loss is proportional to the length; i.e.: for 50 ft., one-half of the above; for 400 ft., four times the above, etc. NOTES:. These figures are for estimating - different types of pipe and hose may have rougher linings and cause higher pressure drops. 2. Couplings and fittings increase the pressure drop some. 3. Lower initial pressures cause increased pressure drop. 4. Higher initial pressure causes lower pressure drop. Piping for a sample system of 3,000 CFM at 00 PSIG of central air, with five 600 CFM uses figured according to the chart for loss of air pressure due to friction. FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE CONTINUED LINE PRESSURE - PSIG NOMINAL CFM PIPE SIZE FREE AIR /2 SCHEDULE

15 FRICTION OF AIR IN HOSE - Pulsating Flow* CONTINUED SIZE OF HOSE, GAUGE COUPLED PRESSURE EACH END, IN. AT LINE, LB. /4 /2 CU.FT. FREE AIR PER MIN. PASSING THROUGH 50 FT. LENGTHS OF HOSE LOSS OF PRESSURE (PSI) IN 50 FT. LENGTHS OF HOSE *For longer or shorter lengths of hose, the friction loss is proportional to the length, i.e.: for 25 ft. one-half of the above; for 50 ft., three times the above, etc. FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE CONTINUED NOMINAL CFM PIPE SIZE FREE AIR /2 SCHEDULE 40 LINE PRESSURE - PSIG

16 DECIMAL AND METRIC EQUIVALENTS OF COMMON FRACTIONS OF AN INCH FRACTION DECIMAL Mm / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / FRICTION LOSS OF AIR IN PIPE - PRESSURE LOSS IN POUNDS FOR EACH 00 FEET OF STRAIGHT PIPE LINE PRESSURE - PSIG NOMINAL CFM PIPE SIZE FREE AIR /2 SCHEDULE /4 SCHEDULE