C =

C =

C =

C = COMPRESSOR CAPACITY IN CFM

V = RECEIVER & PIPING VOLUME IN CU. FT.

P2 = FINAL CUT OUT PRESSURE PSIA= 100 PSIG + 14.7 = 114.7 PSIA

P1 = INITIAL PRESSURE PSIA= 70 PSIG + 14.7 = 84.7 PSIA

V (P2 - P1) 60 SEC.(14.7) (TIME-SEC.)

* Assume the receiver and piping volume were 80 cu. ft.* Assume the pump-up time is 15 seconds.Then solve:

(80) (114.7 - 84.7) (60)(14.7) (15)

144,000220.5

C = 653 cubic ft./min. = actual capacity of existing air compressor

1

DETERMINING YOURAIR REQUIREMENTS

A relatively simple procedure to see if additional compressor capacity(CFM) is required can be performed in any plant or compressedair-using operation.Most general compressor air operations supply 100 PSIG at thecompressor and deliver a minimum of 90 PSIG to the using air tool. Forlowest possible power cost, this means compressor has a “cut outpressure” or unloads at 100 PSIG and “cut-in” or loads at 90 PSIGreceiver or system pressure. With these known figures (or whateverunload and load figures a particular system utilizes), we can determinethe following:If the receiver is below the normal cut-in point (90 PSIG) or does notgradually rise to the cut-out point (100 PSIG), more air is probablyneeded. Always check, of course, that there are no significant leaksand that the unloading and control system on the compressor arefunctioning correctly.NOTE: If the compressor must operate at more than 100 PSIG to get90 PSIG at the tools, check the distribution system for piping size orcheck points. The pipe may be too small or a single choke point toosmall for the system’s total demand (flow) or length.

CHECKING EXISTINGCOMPRESSOR CAPACITY

Running a timed pump-up test is a relatively accurate way to checkyour existing air compressor’s capacity or output. This will confirm thatyour shortage of compressed air is not due to a worn unit or amalfunction.Check the receiver volume in cubic feet. Check the pipe volumebetween the compressor and receiver in cubic feet. Operate thecompressor at load. Close the air valve between the receiver and plantair system. Drain the receiver down to 70 PSIG. Close the drain valvequickly. Record in seconds the required time to pump to 100 PSIG.Now work the following equation:If this is close to the rated capacity of your air compressor, then you canbe relatively sure the demand on your air system is too high and youneed additional air.

28

GENERAL TERMS CONTINUED

PISTON DISPLACEMENT:Is the volume swept by the piston, generally expressed in cubic feet perminute (CFM). For multi-stage compressors, the piston displacementof 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 thedischarge system by the compressor at rated speed and under ratedpressure conditions. Actual capacity is expressed in cubic feet perminute at the temperature and pressure conditions existing at the inletto the first stage.

VOLUMETRIC EFFICIENCY:Is the ratio of actual capacity to piston displacement, generally statedas percentage.

FREE AIR:Generally describes air at room or ambient temperatures and pressures,that is, normal atmospheric conditions. In other words, the term free airdescribes the air actually taken into the suction of a compressor whichtakes air from the surrounding atmosphere.

STANDARD CONDITIONS:Are not universally defined; therefore, since compressor capacities aresometimes expressed in standard cubic feet per minute (SCFM), it isnecessary to identify, before the compressor can be sized, (1) thestandard pressure condition; (2) the standard temperature condition;(3) the compressor suction pressure condition, and; (4) thecompressor suction temperature condition. The most popularidentification for standard pressure and temperature conditions is 14.5PSIA or 60❍F.

BRAKE HORSEPOWER (bhp):Is the measured horsepower input at the compressor shaft. Thehorsepower output of the driver must equal or exceed the compressorbhp plus any drive losses.

LOAD FACTOR:Is the ratio of the available demand for compressed air during a certainperiod of time to the maximum rated output capacity of the compressor.

NOTES:

326

TERMINOLOGY CONTINUED

UNLOAD (No Load):Air compressor continues to run (usually at FULL RPM), but NO air isdelivered because intake is either “closed off” or “modified”, NOT allow-ing inlet air to be trapped.

“MODULATING” UNLOAD:Air compressor continues to run and air supply is matched to demandby “partial unloading”. This is usually accomplished by a “regulatorcontrolled floating inlet”.

START-STOP CONTROL:Air supply is matched to demand by actual starting and stopping of theunit.

CUT-IN/CUT-OUT PRESSURE:The settings on a pressure switch used to either “load or unload” the aircompressor on “constant speed” application. The “cut-out” pressure isalso referred to as “maximum pressure”, the point at which there is NOAIR DELIVERED. The “cut-in” pressure is also referred as“minimum pressure” - the pressure that the system is allowed to fall tobefore additional air volume is called for. The compressor runs at fullload between cut-in and cut-out.

VARIABLE DISPLACEMENT CONTROLS:Also called “Rotor Length Adjustment” in oil cooled Rotary Screwcontrols. Particularly efficient in holding constant speed from 60% to100% capacity variable speed control. Below this usually goes to “blowdown” and idle.

VARIABLE SPEED CONTROL:Most commonly applied in oil cooled Rotary Screws. Very efficient fromabout 50% to 100% capacity. Below 50% usually defaults to modula-tion of Blow Down and idle.

RATED PRESSURE:The operating pressure at which the air compressor’s performance (CFMand BHP - Horsepower required) is measured.

SPECIFIC POWER:Used to compare air compressor efficiency unless otherwise stated.Usually in form of BHP/100 ACFM or CFM/HP.

GENERAL TERMS

COMPRESSORS:Are machines which compress air or gases from atmospheric pressureto a higher discharge pressure.

BOOSTER COMPRESSORS:Are machines which compress air or gases from a pressure higherthan atmospheric to a still higher discharge pressure.

VACUUM PUMPS:Are machines designed for compressing air or gases from an initialpressure which is below atmospheric to a pressure which is at or closeto atmospheric pressure.

RECIPROCATING COMPRESSORS:Are positive displacement machines used to increase the pressure of adefinite volume of gas by volume reduction. The compressing elementis 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 beused to locate them. The best way to detect leaks is to use anultrasonic acoustic detector, which can recognize the high frequencyhissing sounds associated with air leaks. These portable units consistof directional microphones, amplifiers, and audio filters, and usuallyhave either visual indicators or earphones to detect leaks. A simplermethod is to apply soapy water with a paint brush to suspect areas.Although reliable, this method can be time consuming. Other methodsinclude: smoke sticks, candles, foam, manometers and stethoscopes.Ultrasonic detectors can find mid to large sized leaks. The advantagesof ultrasonic leak detection include: versatility, speed, ease of use, theability to perform tests while equipment is running and the ability to finda wide variety of leaks.

HOLE DIA. AIR LEAKAGE AT 100 PSI COST PER YEARIN. CFM $.06 KWH

1/32 1.62 $1581/16 6.5 $6331/8 26 $2,5321/4 104 $10,130

WHAT DO SYSTEM LEAKS COST?• Determine size of leak either through calculation or actual size of

orifice.

• 1/4 inch orifice can pass 104 CFM @ 100 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$9,946.00.

USEFUL FORMULAS

1. COMP. RPM =

2. MOTOR PULLEY p.d. =

3. COMP. PULLEY p.d. =

4. MOTOR RPM =

5. FREE AIR = piston displacement x volumetric eff. (%)

=

=

=

=

=

= x

=

motor pulley p.d. x motor RPMcomp. pulley p.d.

comp. pulley p.d. x comp. RPMmotor RPM

motor pulley p.d. x motor RPMcomp. RPM

comp. pulley p.d. x comp. RPMmotor pulley p.d.

6. REQUIRED PISTON free airDISPLACEMENT vol. eff.

7. PISTON DISPLACE- Cyl. bore x Cyl. bore x stroke in In. x RPMMENT IN CU.FT. MIN* 2200

8. CU. FT. COM- cu. ft. free air x atmospheric pressurePRESSED AIR (PSIG + 14.7)

9. CU. FT. cu. ft. compressed air x (PSIG + 14.7)FREE AIR atmospheric pressure

10. CU. FT. FREE AIRREQ’D TO RAISE vol. of rec. in cu. ft. x PSIGREC. FROM 0 GAUGE atmospheric pressureTO FINAL PRESSURE

11. CU. FT. FREE AIRREQ’D TO RAISE REC.FROM SOME PRESS. vol. of rec. (final PSIG – initial PSIG)GREATER THAN 0 in cu. ft. (atmospheric pressure)GAUGE TO A FINALHIGHER PRESSURE

12. PISTON SPEED IN 2 x stroke (in inches) x RPMFT. PER MIN. 12

13. GALLONS =

14. CU. FT. = gallons x .134

15. TOTAL FORCE INLBS. OF AIR = xCYLINDER

16. CFM OF FREEAIR REQUIREDTO OPERATE = x xAIR CYLINDER(SINGLE ACTING)

For Double Acting Cylinders Multiply by 2.

* Piston displacement for multi-stage compressors - only the lowpressure cylinder is considered.

cu. ft..134

Area of Cylinder PSIG of airDia. in sq. inches press. used

Vol. of Cyl. Cycles (Gauge Press. + 14.7)in cu. ft. per min. (14.7)

524

INDUSTRIAL TOOLS & EQUIPMENTAIR AVG. FREE NORMAL

PRESSURE EQUIPMENT AIR CONS. LOADRANGE CFM FACTOR**

Always check with tool manufacturers for actual consumption of tools being used.The above are based on averages and should not be considered accurate forany particular make of tools. The free air consumptions listed herein are basedon the use of the normal load factors shown in the adjacent column. Load factoris a percentage that expresses the normal actual usage of air as compared tothe maximum usage that will occur if the tool’s throttle valve is turned fully openand the tool is operated continuously at maximum capacity (Load factors shouldbe adjusted based on your own individual operating conditions).

ANTICIPATING YOURFUTURE AIR REQUIREMENTS

The following charts will be helpful to anyone planning a future air system orrequirement. Remember, these are averages for various types of tools and youshould always consult the manufacturer for exact air requirements and analyzeyour own operation to evaluate normal.

90-100 *Dusting Gun (Blow Gun) 3.0 10%90-100 *Drill, 1/6” to 1/8” 4.0 25%90-100 *Drill, 3/8” to 5/8” 7.0 25%90-100 *Screwdriver, #2 to #6 Screw 1.0 15%90-100 *Screwdriver, #6 to 5/16” Screw 3.0 15%90-100 *Tapper, to 3/4” 3.0 15%90-100 *Nutsetters, to 3/8” 3.0 15%90-100 *Nutsetters, to 3/4” 5.0 15%90-100 *Impact Wrench, 3/8” sq.dr. 2.0 20%90-100 *Impact Wrench, 1/2” sq.dr. 3.5 20%90-100 *Impact Wrench, 5/8” sq.dr. 5.0 20%90-100 *Impact Wrench, 3/4” sq.dr 7.5 20%90-100 *Impact Wrench, 1” sq.dr. 10.0 20%90-100 *Die Grinder, Small 4.0 30%90-100 *Die Grinder, Medium 5.0 30%90-100 *Horizontal Grinder, 2” 10.0 30%90-100 *Horizontal Grinder, 4” 14.0 30%90-100 *Horizontal Grinder, 6” 16.0 30%90-100 *Horizontal Grinder, 8” 20.0 30%90-100 *Vertical Grinders & Sanders,

5” Pad 10.0 30%90-100 *Vertical Grinders & Sanders,

7” Pad 14.0 30%90-100 *Vertical Grinders & Sanders,

9” Pad 20.0 30%90-100 *Filing & Sowing Mach., small 3.0 15%90-100 *Filing & Sowing Mach., large 5.0 15%90-100 *Burring Tool, small 4.0 30%90-100 *Burring Tool, large 5.0 30%90-100 *Bench Rammer 5.0 40%90-100 *Floor Rammer 7.0 40%90-100 *Backfill Tamp 15.0 40%90-100 *Compression Riveter 1.0 10%90-100 *Automatic Drills 6.0 25%90-100 *Air Motor, 1 HP 10.0 25%90-100 *Air Motor, 2 HP 15.0 25%90-100 *Air Motor, 3 HP 20.0 25%90-100 *Air Motor Hoist, 1000# 5.0 10%90-100 *Air Motor Hoist, 2000# 5.0 10%90-100 *Cylinder Type Hoist 1.5 10%

HAMMERS90-100 *Scaling Hammer 4.0 35%90-100 *Chipping Hammer 7.0 35%90-100 *Riveting Hammer 15.0 35%

SPRAY GUNS90-100 *Point Spray Gun (Production) 8.5 50%90-100 *Point Spray Gun (Touch-up) 3.5 25%

* ORIFICES ARE REQUIRED

1515

1515

1520

3045

6080

9010

011

015

020

022

525

035

045

060

080

0

45.

68

1010

1525

3040

6080

100

100

150

200

200

300

350

400

500

600

722

14” x 33” 20 2.7 12.0 20.8 25.3 30.0 34.4 38.9

16’” x 38” 30 4.0 18.0 31.2 38.0 45.0 51.6 58.4

20” x 48” 60 8.0 36.0 62.4 76.0 90.0 103.2 116.8

20” x 63” 80 10.7 48.0 83.2 101.3 120.0 137.6 155.7

24” x 67” 120 16.0 72.0 124.8 152.0 180.0 206.4 233.6

30” x 84” 240 32.0 144.0 249.6 304.0 360.0 412.8 467.2

50 1.8 5.0 10.1 18.160 1.3 4.0 8.4 14.8 23.470 1.0 3.4 7.0 12.4 20.0 28.4

1/2 80 0.9 2.8 6.0 10.8 17.4 25.2 34.690 0.8 2.4 5.4 9.5 14.8 22.0 30.5 41.0

100 0.7 2.3 4.8 8.4 13.3 19.3 27.2 36.6110 0.6 2.0 4.3 7.6 12.0 17.6 24.6 33.3 44.5

50 0.4 0.8 1.5 2.4 3.5 4.4 6.5 8.5 11.4 14.260 0.3 0.6 1.2 1.9 2.8 3.8 5.2 6.8 8.6 11.270 0.2 0.5 0.9 1.5 2.3 3.2 4.2 5.5 7.0 8.8 11.0

3/4 80 0.2 0.5 0.8 1.3 1.9 2.8 3.6 4.7 5.8 7.2 8.8 10.690 0.2 0.4 0.7 1.1 1.6 2.2 3.1 4.0 5.0 6.2 7.5 9.0

100 0.2 0.4 0.6 1.0 1.4 2.0 2.7 3.5 4.4 5.4 6.6 7.9110 0.1 0.3 0.5 0.9 1.3 1.8 2.4 3.1 0.9 4.9 5.9 7.1

50 0.1 0.2 0.3 0.5 0.8 1.1 1.5 2.0 2.6 3.5 4.8 7.060 1.1 0.2 0.3 0.4 0.6 0.8 1.2 1.5 2.0 2.6 3.3 4.270 -- 0.1 0.2 0.4 0.5 0.7 1.0 1.3 1.6 2.0 2.5 3.1

1 80 -- 0.1 0.2 0.3 0.5 0.7 0.8 1.1 1.4 1.7 2.0 2.490 -- 1.1 0.2 0.3 0.4 0.6 0.7 0.9 1.2 1.4 1.7 2.0

100 -- 1.1 0.2 0.2 0.4 0.5 0.6 0.8 1.0 1.2 1.5 1.8110 -- 0.1 0.2 0.2 0.3 0.4 0.6 0.7 0.9 1.1 1.3 1.5

FRICTION OF AIR IN HOSE

HOSESIZE

GAUGE CU. FT. OF AIR PER MINUTE AT 80 PSIGPRESSURE 20 30 40 50 60 70 80 90 100 110 120 130

OF LINE LOSS OF PRESSURE (PSI) IN 50 FT. LENGTHS OF HOSE

These devices are to be considered as continuously operating deviceswhen operating normally. All other devices listed are to be consideredas intermittently operated when operating normally. When the devicesconsist of a large number of the continuously operated type, and if only afew are to be used at one time, the compressor should have a capacityat least equal to the total consumption of all those tools usedsimultaneously, in addition to the consumption of all the intermittentlyoperated tools, if any.**Normal load factor is the percentage of time the throttle valve is openduring normal use.

COMPRESSED AIR RECEIVERCAPACITY

CAPACITYIN

GALLONS

TANKDIMENSION

CAPACITY IN CU.FT. OF FREE AIRAT GAUGE PRESSURE SHOWN

0 50 100 125 150 175 200

TH

RE

E P

HA

SE

MO

TOR

DA

TA -

For

60

Hz

1800

RP

M S

tand

ard

Mot

orM

OTOR

1 /2

3 /41

11 /22

35

71 /210

1520

2530

4050

6075

100

125

150

200

1515

1515

1520

3550

6090

100

110

125

175

200

250

300

400

600

600

800

46.

258

1010

17.5

2540

5060

9010

012

517

520

025

030

040

050

060

0--

MOT

ORSY

STEM

200V

(208

V)

MOT

ORSY

STEM

230V

(240

V)

2.5

3.7

4.8

6.9

7.8

11.0

17.5

25.3

32.2

48.3

62.1

78.2

9212

015

017

722

128

535

941

455

2

1414

1414

1414

1210

86

43

21/

03/

04/

030

050

02-

4/0

2-30

02-

500

2.2

3.2

4.2

6.0

6.8

9.6

15.2

2228

4254

6880

104

130

154

192

248

312

360

480

1414

1414

1414

1410

106

44

31

2/0

3/0

250

350

2-3/

02-

4/0

2-35

0

FULL

LOA

D CU

RREN

T(N

EC) -

AM

PS M

INIM

UMCO

PPER

WIR

E SI

ZE -

(75❍

C) TH

W, T

HHN-

THW

N, X

HHW

- SI

ZECI

RCUI

T BRE

AKER

Ther

mal-M

agne

tic B

reak

erTri

p Ra

ting -

AM

PSFU

SIBL

E SW

ITCH

With

Dua

l Ele

men

t Tim

eDe

lay F

use -

AM

PSFU

LL L

OAD

CURR

ENT

(NEC

) - A

MPS

MIN

IMUM

COPP

ER W

IRE

SIZE

-(7

5❍

C) TH

W, T

HHN-

THW

N, X

HHW

- SI

ZECI

RCUI

T BRE

AKER

Ther

mal-M

agne

tic B

reak

erTri

p Ra

ting -

AM

PSFU

SIBL

E SW

ITCH

With

Dua

l Ele

men

t Tim

eDe

lay F

use -

AM

PS

W =

Table is based on 100% coefficient of flow. For well rounded entrance, multiply valuesby 0.97. For sharp edged orifices a multiplier of 0.61 may be used for approximateresults. Values for pressures from 1 to 15 lbs. gauge calculated by standard adiabaticformula. Values for pressures above 15 lbs. gauge calculated by approximate formulaproposed by S.A.

Moss. Where:0.5303 ACp1 W = discharge in lbs. per sec. T1 A = area of orifice in sq. in.

C = Coefficient of flowP1 = Upstream total pressure in lbs. per sq. in absoluteT1 = Upstream temperature in ❍F abs.Values used in calculating above table were:C = 1.0, p1 = gauge pressure + 14.7 lbs./sq. in.T1 = 530 ❍F abs.Weights (W) were converted to volumes using density factor of 0.07494 lbs./cu. ft. This iscorrect for dry air 14.7 lbs. per sq. in. absolute pressure and 70❍F. Formula cannot be usedwhere p1 is less than two times the downstream pressure.

20 9

DIAMETER OF ORIFICE1/64” 1/32” 1/16” 1/8” 1/4” 3/8” 1/2” 5/8” 3/4” 7/8” 1”

Discharge in cubic feet of free air per minute1 .028 .112 .450 1.80 7.18 16.2 28.7 45.0 64.7 88.1 1152 .040 .158 .633 2.53 10.1 22.8 40.5 63.3 91.2 124 1623 .048 .194 .775 3.10 12.4 27.8 49.5 77.5 111 152 1984 .056 .223 .892 3.56 14.3 32.1 57.0 89.2 128 175 2285 .062 .248 .993 3.97 15.9 35.7 63.5 99.3 143 195 2546 .068 .272 1.09 4.34 17.4 39.1 69.5 109 156 213 2787 .073 .293 1.17 4.68 18.7 42.2 75.0 117 168 230 3009 .083 .331 1.32 5.30 21.2 47.7 84.7 132 191 260 339

12 .095 .379 1.52 6.07 24.3 54.6 97.0 152 218 297 38815 .105 .420 1.68 6.72 26.9 60.5 108 168 242 329 43020 .123 .491 1.96 7.86 31.4 70.7 126 196 283 385 50325 .140 .562 2.25 8.98 35.9 80.9 144 225 323 440 57530 .158 .633 2.53 10.1 40.5 91.1 162 253 365 496 64835 .176 .703 2.81 11.3 45.0 101 180 281 405 551 72040 .194 .774 3.10 12.4 49.6 112 198 310 446 607 79345 .211 .845 3.38 13.5 54.1 122 216 338 487 662 86550 .229 .916 3.66 14.7 58.6 132 235 366 528 718 93860 .264 1.06 4.23 16.9 67.6 152 271 423 609 828 108270 .300 1.20 4.79 19.2 76.7 173 307 479 690 939 122780 .335 1.34 5.36 21.4 85.7 193 343 536 771 1050 137190 .370 1.48 5.92 23.7 94.8 213 379 592 853 1161 1516

100 .406 1.62 6.49 26.0 104 234 415 649 934 1272 1661110 .441 1.76 7.05 28.2 113 254 452 705 1016 1383 1806120 .476 1.91 7.62 30.5 122 274 488 762 1097 1494 1951125 .494 1.98 7.90 31.6 126 284 506 790 1138 1549 2023150 .582 2.37 9.45 37.5 150 338 600 910 1315 1789 2338200 .761 3.10 12.35 49.0 196 441 784 1225 1764 2401 3136250 .935 3.80 15.18 60.3 241 542 964 1508 2169 2952 3856300 .995 4.88 18.08 71.8 287 646 1148 1795 2583 3515 4592400 1.220 5.98 23.81 94.5 378 851 1512 2360 3402 4630 6048500 1.519 7.41 29.55 117.3 469 1055 1876 2930 4221 5745 7504750 2.240 10.98 43.85 174.0 696 1566 2784 4350 6264 8525 11136

1000 2.985 14.60 58.21 231.0 924 2079 3696 5790 8316 11318 14784

DISCHARGE OF AIRTHROUGH AN ORIFICE

In cubic feet of free air per minute at standard atmospheric pressure of14.7 lb. per sq. in. absolute and 70❍F

GAUGEPRESSURE

BEFOREORIFICEIN LBS.

PERSQ.IN.

FRIC

TIO

N L

OS

S O

F A

IR I

N P

IPE

- P

RE

SS

UR

E L

OS

S I

N P

OU

ND

S F

OR

EA

CH

100

FE

ET

OF

ST

RA

IGH

T P

IPE

CO

NT

INU

ED

300

.36

.30

.26

.20

.16

.13

.10

500

.94

.78

.67

.52

.43

.36

.26

.20

.17.1

4.1

175

01.

691.

441.

12.9

2.7

8.5

6.4

4.3

6.3

0.2

3.1

9.1

6.1

410

002.

501.

941.

591.

34.9

7.7

6.6

2.5

3.4

1.3

3.2

8.2

415

004.

303.

522.

982.

151.

681.

381.

17.9

0.7

3.6

1.5

320

005.

293.

812.

992.

472.

081.

601.

301.

09.9

425

005.

964.

673.

833.

262.

502.

021.

701.

4730

008.

586.

715.

514.

683.

582.

912.

452.

1135

009.

157.

506.

374.

893.

963.

342.

8840

0011

.99.

808.

316.

365.

164.

353.

7645

0012

.410

.58.

066.

555.

504.

7550

0015

.313

.09.

958.

076.

805.

8660

0014

.311

.69.

788.

4570

0019

.515

.913

.411

.5

3”SC

HEDU

LE40

NOM

INAL

CFM

PIPE

SIZ

EFR

EE A

IRLI

NE P

RESS

URE

- PSI

G10

1520

3040

5075

100

125

150

200

250

300

350

501.

85.

010

.118

.160

1.3

4.0

8.4

14.8

23.4

701.

03.

47.

012

.420

.028

.480

0.9

2.8

6.0

10.8

17.4

25.2

34.6

900.

82.

45.

49.

514

.822

.030

.541

.010

00.

72.

34.

88.

413

.319

.327

.236

.611

00.

62.

04.

37.

612

.017

.624

.633

.344

.550

0.4

0.8

1.5

2.4

3.5

4.4

6.5

8.5

11.4

14.2

600.

30.

61.

21.

92.

83.

85.

26.

88.

611

.270

0.2

0.5

0.9

1.5

2.3

3.2

4.2

5.5

7.0

8.8

11.0

800.

20.

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92.

83.

64.

75.

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0.6

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2.7

3.5

4.4

5.4

6.6

7.9

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11.1

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4.9

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60.

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270

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20.

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50.

71.

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62.

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53.

13.

84.

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11.

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72.

02.

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73.

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70.

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0.5

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110

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60.

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91.

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1

11

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1.93

1.51

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2.75

2.15

1.77

1.50

1.05

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800

4.87

3.82

3.13

2.66

2.04

1.65

1.39

1.20

1000

7.55

5.90

4.85

4.12

3.16

2.56

2.16

1.86

1250

9.12

7.49

6.35

4.87

3.96

3.32

2.87

1500

10.8

9.17

7.02

5.70

4.80

4.14

1750

12.5

9.54

7.74

6.50

5.62

2000

16.3

12.5

10.1

8.50

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2250

15.8

12.8

10.8

9.30

2500

19.4

15.8

13.3

11.4

2”SC

HEDU

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NOM

INAL

CFM

PIPE

SIZ

EFR

EE A

IRLI

NE P

RESS

URE

- PSI

G10

1520

3040

5075

100

125

150

200

250

300

350

1316

Inle

t tem

pera

ture

125

120

115

110

105

100

9590

Inle

t wat

er va

por -

lbs./

hr.

4.71

684.

1008

3.55

523.

0756

2.65

322.

2836

1.95

801.

6764

Lbs.

wate

r rem

oved

/hr.

4.29

003.

6740

3.12

842.

6588

2.22

641.

8565

1.53

121.

2496

Wat

er re

mov

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erce

nt90

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89.5

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223

9.9

204.

317

2.9

145.

412

1.1

100.

081

.6Se

nsib

le lo

ad -

btu.

/hr.

3181

2969

2757

2545

2333

2121

1908

1697

Late

nt lo

ad -

btu.

/hr.

4595

3935

3351

2837

2425

1989

1640

1338

Tota

l load

- btu

./hr

.76

7668

9461

0853

8247

5841

1035

4830

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7.4

1.3

6.3

1.2

7

Tabl

e 1.

Ref

riger

ated

Air

Drye

r Per

form

ance

(11

data

per

100

CFM

@ 1

00 P

SIG)

50❍

F Dew

-Poi

nt U

nit

35❍

F Dew

-Poi

nt U

nit

Inle

t tem

pera

ture

125

120

115

110

105

100

9590

Inle

t wat

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por -

lbs./

hr.

4.71

684.

1008

3.55

523.

0756

2.65

322.

2836

1.95

801.

6764

Lbs.

wate

r rem

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/hr.

4.47

923.

8632

3.31

762.

8380

2.41

562.

0460

1.72

041.

4388

Wat

er re

mov

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erce

nt94

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94.2

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.31

92.2

791

.10

89.6

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84.8

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260.

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4.15

192.

816

4.9

140.

411

8.9

100.

083

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nsib

le lo

ad -

btu.

/hr.

3818

3605

3393

3181

2969

2757

2544

2332

Late

nt lo

ad -

btu.

/hr.

4797

4134

3545

3042

2581

2191

1842

1540

Tota

l load

- btu

./hr

.86

1577

3969

3862

2355

4049

4843

8638

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t of d

esig

n19

6.4

176.

415

9.2

141.

912

6.3

112.

810

0.0

88.3

Oper

atio

n kw.

/hr.

1.10

.99

.89

.78

.71

.63

.56

.49

20.4

5.3

8.3

2.2

5.2

0.17

.13

.10

351.

291.

07.9

2.7

1.5

8.4

9.3

5.2

8.2

3.1

9.1

5.1

2.1

050

1.81

1.40

1.15

.97

.70

.55

.45

.38

.29

.24

.20

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3.10

2.53

2.14

1.54

1.21

.99

.84

.65

.52

.44

.38

100

4.39

3.70

2.68

2.09

1.72

1.46

1.12

.91

.76

.66

125

5.70

4.10

3.22

2.64

2.24

1.72

1.39

1.17

1.01

150

5.88

4.60

3.78

3.20

2.46

1.99

1.68

1.45

200

8.05

6.61

5.61

4.30

3.49

2.94

2.53

250

10.3

8.87

6.72

5.45

4.59

3.96

300

12.6

9.66

7.85

6.60

5.70

400

17.2

14.0

11.7

10.1

500

21.8

18.3

15.8

LINE

PRE

SSUR

E - P

SIG

1015

2030

4050

7510

012

515

020

025

030

035

0

1”SC

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N L

OS

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F A

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INU

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NOM

INAL

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EFR

EE A

IR

DETERMINING ADDITIONALCOMPRESSED AIR REQUIRED TO

BRING YOUR AIR SYSTEMBACK TO 100 PSIG

Once the actual existing compressed air capacity is known, it isrelatively easy to mathematically determine the air required to bring theair system up to 100 PSIG:

CFM P2

P1

653 (114.7) = 884 CFM84.7

Therefore, the total air capacity required to hold 100 PSIG is 884 CFMand the additional then is 884 - 653 or 231 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 generallyfrom 20% to 30% depending on the condition.

Using a 20% extra capacity factor, the total air requirement would thenbe 884 x 1.20 = 1060 CFM and an additional (1060 - 653) 408 CFMwould be recommended.

ANALYZING THE COST OFSYSTEM LEAKS

A shortage in capacity is often due to or certainly partially due to systemleakage. Air system leaks are a continuing source of lost power andshould always be minimized. A number of small leaks to that of a 1/4”orifice would at 100 PSIG pass CFM of compressed air. This is a25HP air compressor to you. A .04 per KWH operating 8,000 hoursper year, (3 shifts) this would cost you $6,600 in power cost to do nowork.

Defective tools, shut-off valves, packings, fit-ups, drain cocks, etc.,should be continually checked. Most plants can always afford themaintenance labor and parts to correct leaks. Total system leakagecan be identified by measuring time in seconds for the system (receiver)pressure to drop from 100 to 90 PSIG with no air supply or usage:

For example, assume the total receiver and piping of the system is 120cubic feet. If the plant has a 90 second bleed down rate is 90 PSIGwhen no production air is being used, this is leakage.

The calculated leakage capacity is:

(120) (114.7 - 104.7) (60) = 54 CFM(90) 14.7

TOTAL COMPRESSED AIR LEAKAGE = 54 CFM X 1.15 = 62 CFM

* Add 15% to adjust for the higher leakage rate at the 120 PSIG to 90PSIG (30 PSIG x .5)

* Any leakage rate beyond 5% of the total system should be corrected.

CFM (REQUIRED) =

CFM (REQUIRED) =

CFM (LEAKAGE) =

2 27

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 thecompressing element.

DOUBLE-ACTING COMPRESSORS:Are machines which compress on both sides of the piston. Therunning gear consists of a crank and crosshead mechanism with thepiston rod attached to the crosshead, and extending into thecompressor cylinder through a packing box. Compression takes placeon both strokes in each revolution.

AIR RECEIVERS:Are large tanks placed in compressed air systems. A receiver actsprimarily as a pulsation damper and warehouse for air. It also serves tocollect condensate. Consequently, it is advisable to equip receiverswith automatic moisture traps.

SINGLE STAGE COMPRESSORS:Are machines which use only one step or stage to compress from theinitial pressure to the final discharge pressure.

MULTI-STAGE COMPRESSORS:Are machines which use more than one step or stage to compress fromthe initial pressure to the final discharge pressure. For example, a twostage compressor compresses in two steps; a three stage compressorcompresses in three steps, etc.

INTERCOOLERS:Are heat exchangers used to remove the heat of compression betweenstages of compression on multi-stage compressors.

AFTERCOOLERS:Are heat exchangers designed to remove the heat of compression afterthe final stage of compression in addition to removing moisture fromthe compressed air.

MOISTURE SEPARATORS:Are used generally in conjunction with aftercoolers and intercoolers tocollect and remove the moisture which has condensed in compressedair lines.

AUTOMATIC MOISTURE TRAPS:Are devices designed to automatically eject from the system themoisture collected in the separator.

ABSOLUTE PRESSURE:Is the existing gauge pressure (as read on a gauge) plus atmosphericpressure. Atmospheric pressure at sea level is 14.7 PSIA; therefore,for 100 pounds gauge, the absolute pressure (PSIA) is 100 plus 14.7,or 114.7 PSIA.

RATIO OF COMPRESSION:Is the absolute discharge pressure divided by the absolute suctionpressure. For a compressor taking in atmospheric air at sea level andcompressing it to 100 pounds gauge, the ratio of compression is114.7/114.7 = 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 internalcombustion engine manufacturers. In engines, ratio of compression isa ratio of volumes)

HP x .746 x HRS. x RATEMOTOR EFFICIENCY

WHAT IS ELECTRIC ENERGY COST?

ELECTRIC ENERGY COST (DOLLARS) =

This is the formula for electric energy cost in dollars, and you can see itis 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 comparisonpurposes. (Your actual power bill can be further affected positively ornegatively by such things as Power Factor - Demand Charges, etc.).

THE MAGNITUDE OFENERGY COST (ELECTRIC)!

To see the magnitude of your potential expenditure in power cost,calculate the power cost of a 100 HP Air Compressor:

• 6,000 hours a year• Rate of $.07/kW• Motor efficiency .90

(100) (.746) (6,000) (.07).90

ELECTRIC ENERGY COST = $34,800 PER YEAR

A 100 HP Air Compressor would have a $34,800 per year power cost.

The initial purchase price of a 100 HP Air Compressor, lubricated, forplant air will probably range from $35,000 to $50,000 depending on thetype.

In short, the ELECTRIC ENERGY COST OF OPERATION in a HeavyDuty Cycle-Full Load 6,000 Hours (2 Shifts Plus)) CAN EQUAL OREXCEED THE INITIAL COST OF THE UNIT EVERY YEAR. Perhapswe should pay attention to this often overlooked continuing cost. APOSITIVE VARIANCE OF 15% - 25% in energy cost can be asignificant savings in any operation, and this is obtainable.

CONVERSION FACTORS

4 25

TERMINOLOGY

CFM DISPLACEMENT:CUBIC FEET PER MINUTE measures the volume “displaced” by theair 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 ratedpressure.

ICFM:“INLET” CFM is rated volume of “Inlet” air (at “Inlet” conditions i.e.:temperature and pressure 14.7 PSIG at sea level) taken in to thecompressor.

ACFM:Is the actual cubic feet per minute of inlet compressed air delivered tothe system at a specified point at the final discharge pressure. i.e.: thecompressor delivers 625 ACFM of compressed air at 100 PSIG at thedischarge end of the aftercooler.

SCFM:Standard Cubic Feet Per Minute is ACFM or ICFM CONVERTED to“standard” intake conditions - (60❍F, 0% RH & 14.7 PSIG usually) forrating 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 - 14.7 PSIA or 0 PSIG (gauge pressure).

PSIG:Gauge pressure shows amount of air pressure above ambient; i.e.:Sea level = 0 PSIG = 14.7 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 andDischarge delivering maximum volume (ACFM) at Rated Pressure(PSM).

FOR EXAMPLE

Inlet = 700 ICFM Compressed to 625 ACFMat 14.7 PSIA, 0 PSIG at 114.7 PSIA, 100 PSIG

Kilowatt Hours (kW h) Horsepower Hours (hp h) 1.341 0

Watts (W) Horsepower (hp) 0.001341 0

TO CONVERT FROM TO DIVIDED BY

Bars Pounds Force per Sq. In. (lbf/in2) (PSI) 14.504

ELECTRIC ENERGY COST =

TO CONVERT FROM TO MULTIPLY BY

1515

1515

1515

1515

2035

4560

6080

9010

011

015

020

020

025

0

1.8

2.5

3.2

45

6.25

1015

2025

3040

5060

8090

100

150

175

200

300

6 23

AUTOMOTIVE SERVICEEQUIPMENT

AIR AVG. FREEPRESSURE EQUIPMENT AIR CONS.

RANGE CFM

70- 100 *Air Filter Cleaner 3.070- 100 *Body Polisher 2.070- 100 *Body Sander (Orbital) 5.070- 100 *Brake Tester 3.570- 100 *Carbon Remover 3.070- 100 *Carwasher 8.590- 100 Dusting Gun (Blow Gun) 2.5

120- 150 *Grease Gun 3.070- 100 *Panel Cutter 4.070- 90 Drill, 1/16” to 3/8” 4.0

125- 150 *Impact Wrench, 3/8” sq.dr. 2.0125- 150 *Impact Wrench, 1/2” sq.dr. 3.5125- 150 *Impact Wrench, 5/8” sq.dr. 5.0125- 150 *Impact Wrench, 3/4” sq.dr. 7.5125- 150 *Impact Wrench, 1” sq.dr. 10.0

70- 90 *Die Grinder 5.090- 100 *Vertical Disc Sanders 10.090- 100 *Filing & Sawing Machine, small 3.090- 100 *Filing & Sawing Machine, large 5.0

90- 100 *Burring Tool 5.0145- 175 Hydraulic Lift 6.0125- 150 Hydraulic Floor Jack 6.0120- 150 Pneumatic Garage Door 3.0

90- 100 Radiator Tester 1.090- 100 Spark Plug Cleaner 5.090- 100 Spark Plug Tester 0.5

HAMMERS

90- 100 *Air Hammer 4.090- 100 *Tire Hammer 12.0

125- 150 *Bead Breaker 12.0

SPRAY GUNS

90- 100 *Engine Cleaner 5.090- 100 *Paint Spray Gun (Production) 8.590- 100 *Paint Spray Gun (Touch-up) 3.590- 100 *Paint Spray Gun (Undercoating) 19.090- 100 Spring Oiler 4.0

TIRE TOOLS

125- 150 Rim Stripper 6.0125- 150 Tire Changer 1.0125- 150 Tire Inflation Line 1.5125- 150 Tire Spreader 1.0125- 150 *Vacuum Cleaner 6.5 TH

RE

E P

HA

SE

MO

TO

R D

ATA

- F

or 6

0 H

z 18

00 R

PM

Sta

ndar

d M

otor

CO

NT

INU

ED

MOT

OR

1 /23 /4

111 /2

23

571 /2

1015

2025

3040

5060

7510

012

515

020

0

1515

1515

1515

1520

2540

6070

8090

100

110

125

200

225

250

350

23.

24

5.6

6.25

815

2020

3040

5060

8010

010

015

017

520

025

035

0

MOT

ORSY

STEM

460V

(480

V)

MOT

ORSY

STEM

575V

(600

V)

1.1

1.6

2.1

3.0

3.4

4.8

7.6

1114

2127

3440

5265

7796

124

156

180

240

1414

1414

1414

1414

1410

108

86

43

12/

03/

04/

035

0

0.9

1.3

1.7

2.4

2.7

3.9

6.1

9.0

1117

2227

3241

5262

7799

125

144

192

1414

1414

1414

1414

1412

1010

86

64

31

2/0

3/0

250

FULL

LOA

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T(N

EC) -

AM

PS M

INIM

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WIR

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(75❍

C) TH

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HHN-

THW

N, X

HHW

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Ther

mal-M

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reak

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SIBL

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ITCH

With

Dua

l Ele

men

t Tim

eDe

lay F

use -

AM

PSFU

LL L

OAD

CURR

ENT

(NEC

) - A

MPS

MIN

IMUM

COPP

ER W

IRE

SIZE

-(7

5❍

C) TH

W, T

HHN-

THW

N, X

HHW

- SI

ZECI

RCUI

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Ther

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With

Dua

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t Tim

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use -

AM

PS

8 21

1/8” 115 130 140 165

3/16” (*3) 260 290 320 375

1/4” (*4) 460 500 560 660

5/16” (*5) 725 825 900 1050

3/8” (*6) 1050 1155 1260 1475

7/16” (*7) 1450 1600 1750 2050

1/2” (*8) 1850 2000 2250 2650

5/8” (*10) 2900 3125 3520 4100

3/4” (*12) 4180 4500 5060 5950

1/8” 18 20 22 26

3/16” (*3) 41 45 49 58

1/4” (*4) 72 80 90 105

5/16” (*5) 113 125 140 160

3/8” (*6) 163 182 200 235

7/16” (*7) 215 240 270 315

1/2” (*8) 290 320 350 410

5/8” (*10) 454 500 550 640

3/4” (*12) 652 720 790 925

BLASTING DATA

APPROXIMATE AIR CONSUMPTION(CFM) PER BLAST NOZZLE

NOZZLESIZE

NOZZLE PRESSURE

80 PSI 90 PSI 100 PSI 120 PSI

NOZZLESIZE

NOZZLE PRESSURE

80 PSI 90 PSI 100 PSI 120 PSI

APPROXIMATE ABRASIVECONSUMPTION (LBS./HR.)

PER BLAST NOZZLE

Air volume and pressure are very important. The blasting productionrate will increase with higher blasting pressures and decrease with lowerblasting pressures. The National Association of Corrosion Engineersdata suggests that 1.5% of production is lost for each 1 PSI reduction inblast nozzle pressure. Pressure drop through the blast unit itself isnormally less than 1 PSI. Air pressure loss can be avoided by using theshortest possible hose of adequate size. S

ING

LE P

HA

SE

MO

TOR

DA

TA (

60 H

z)

MOT

ORSY

STEM

115V

(120

V)

MOT

OR

1 /61 /4

1 /31 /2

3 /41

11 /22

35

71 /210

MOT

ORSY

STEM

230V

(240

V)

1515

1520

2530

4050

7090

110

--

6.25

910

1520

2530

3050

8010

0--

FULL

LOA

D CU

RREN

T (NE

C) -

AMPS

MIN

IMUM

COP

PER

WIR

ESI

ZE -

(75❍

C) TH

W, T

HHN-

THW

N,XH

HW -

SIZE

CIRC

UIT B

REAK

ERTh

erm

al-M

agne

tic B

reak

er Tr

ipRa

ting -

AM

PSFU

SIBL

E SW

ITCH

With

Dua

l Ele

men

t Tim

e Del

ayFu

se - A

MPS

FULL

LOA

D CU

RREN

T (NE

C) -

AMPS

MIN

IMUM

COP

PER

WIR

ESI

ZE -

(75❍

C) TH

W, T

HHN-

THW

N,XH

HW -

SIZE

CIRC

UIT B

REAK

ERTh

erm

al-M

agne

tic B

reak

er Tr

ipRa

ting -

AM

PSFU

SIBL

E SW

ITCH

With

Dua

l Ele

men

t Tim

e Del

ayFu

se - A

MPS

2.2

2.9

3.6

4.9

6.9

810

1217

2840

50

1414

1414

1414

1414

1210

86

1515

1515

1515

2025

3560

8090

3.2

4.5

5.6

710

1215

2025

4060

60

4.4

5.8

7.2

9.8

13.8

1620

2434

5680

--

1414

1414

1414

1210

84

3--

10 19

LOSS OF AIR PRESSUREDUE TO FRICTION - IN PSI 100 FT.OF PIPE OR HOSE 100 PSI GAUGE

INITIAL PRESSURE

For longer or shorter lengths of pipe or hose, the friction loss isproportional to the length; i.e.: for 50 ft., one-half of the above; for 400 ft.,four times the above, etc.NOTES:1. 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 100 PSIG of central air, withfive 600 CFM uses figured according to the chart for loss of air pressuredue to friction.

CU. FT. EQUIVALENTFREE CU. FT.AIR COMPRESSED

PER MIN. AIR/MIN.

TYPICALNominal Diameter, In. (I.D.)

1/2 3/4 1 11/4 11/2 2 21/2 3 31/2 4

10 1.28 2.6 .1 .0320 2.56 6.9 .4 .11 .03 .0130 3.84 .59 .9 .25 .06 .0740 5.12 1.6 .45 .10 .0550 6.41 2.5 .69 .16 .07 .0260 7.68 3.6 1.00 .23 .10 .0370 8.96 4.9 1.40 .32 .14 .0480 10.24 6.5 1.80 .41 .18 .05 .0290 11.52 8.3 2.30 .52 .23 .06 .02

100 12.81 2.80 .65 .29 .08 .03125 15.82 4.90 1.0 .45 .12 .05150 19.23 6.30 1.5 .64 .17 .07 .02175 22.40 1.9 .87 .24 .09 .03200 25.62 2.6 1.14 .31 .12 .04 .02250 31.64 4.0 1.79 .49 .19 .06 .03300 38.44 5.8 2.58 .69 .27 .08 .04 .02350 44.80 3.51 .94 .36 .11 .05 .03400 51.24 4.58 1.21 .48 .15 .07 .04450 57.65 5.80 1.54 .59 .19 .09 .05500 63.28 7.16 1.92 .74 .23 .11 .06600 76.88 2.76 1.07 .34 .16 .08700 89.60 3.77 1.45 .46 .21 .11800 102.50 4.90 1.90 .59 .28 .14900 115.30 6.23 2.41 .76 .35 .18

1000 128.10 7.69 2.98 .93 .44 .221500 192.30 6.70 2.10 .98 .492000 256.20 3.74 1.73 .882500 316.40 5.84 2.72 1.383000 384.60 8.41 3.91 2.003500 447.80 5.82 2.724000 512.40 6.94 3.55

FRIC

TIO

N L

OS

S O

F A

IR I

N P

IPE

- P

RE

SS

UR

E L

OS

S I

N P

OU

ND

S F

OR

EA

CH

100

FE

ET

OF

ST

RA

IGH

T P

IPE

CO

NT

INU

ED

150

.29

.24

.22

.16

.13

.11

200

.50

.42

.36

.28

.23

.19

.14

.11

250

.80

.64

.55

.43

.35

.29

.21

.17.1

4.1

230

01.

08.9

0.7

7.6

0.4

9.4

1.3

0.2

3.1

9.1

6.1

3.1

040

01.

571.

341.

04.8

5.7

2.5

2.4

1.3

3.2

8.2

2.1

8.1

5.1

350

02.

071.

601.

311.

11.8

0.6

3.5

1.4

4.3

3.2

7.2

3.2

060

02.

952.

281.

871.

581.

14.8

9.7

3.6

2.4

8.3

9.3

3.2

880

04.

003.

272.

762.

001.

561.

281.

09.8

3.6

8.5

7.4

910

005.

174.

303.

102.

431.

991.

691.

301.

05.8

8.7

612

506.

784.

893.

833.

142.

662.

041.

661.

391.

2015

006.

855.

364.

403.

732.

872.

321.

951.

6820

009.

407.

826.

555.

024.

073.

422.

9625

0012

.110

.37.

866.

395.

364.

6230

0014

.711

.39.

137.

706.

6235

0015

.412

.510

.59.

0240

0020

.016

.313

.711

.8

21 /2”

SCHE

DULE

40

NOM

INAL

CFM

PIPE

SIZ

EFR

EE A

IRLI

NE P

RESS

URE

- PSI

G10

1520

3040

5075

100

125

150

200

250

300

350

12 17

LINE

PRE

SSUR

E - P

SIG

1015

2030

4050

7510

012

515

020

025

030

035

050

.31

.25

.22

.17.1

4.1

275

.65

.54

.46

.36

.29

.25

.18

.14

.12

.10

100

1.13

.94

.80

.62

.51

.43

.31

.24

.20

.17.1

3.1

112

51.

441.

24.9

6.7

8.6

6.4

8.3

7.3

1.2

6.2

0.1

6.1

4.1

215

02.

041.

751.

351.

11.9

4.6

8.5

3.4

3.3

7.2

8.2

3.1

9.17

200

3.04

2.36

1.93

1.63

1.18

.92

.76

.64

.49

.40

.34

.29

250

3.68

3.01

2.54

1.83

1.44

1.18

1.00

.77

.62

.52

.45

300

4.29

3.62

2.62

2.05

1.74

1.43

1.09

.89

.75

.64

400

6.35

4.58

3.59

2.94

2.50

1.92

1.55

1.31

1.13

500

7.12

5.59

4.59

3.89

2.98

2.42

2.03

1.76

600

8.00

6.55

5.55

4.26

3.46

2.91

2.51

700

10.8

8.89

7.55

5.78

4.70

3.95

3.40

800

11.6

9.80

7.50

6.10

5.12

4.42

1000

15.2

11.7

9.45

7.95

6.86

1200

16.4

13.3

11.2

9.61

1400

22.9

18.6

15.6

13.5

11 /2”

SCHE

DULE

40

NOM

INAL

CFM

PIPE

SIZ

EFR

EE A

IR

FRIC

TIO

N L

OS

S O

F A

IR I

N P

IPE

- P

RE

SS

UR

E L

OS

S I

N P

OU

ND

S F

OR

EA

CH

100

FE

ET

OF

ST

RA

IGH

T P

IPE

CO

NT

INU

ED

FRIC

TIO

N O

F A

IR I

N H

OS

E -

Pul

sati

ng F

low

* C

ON

TIN

UE

D

50--

--0.

10.

20.

20.

30.

40.

50.

71.

160

----

--0.

10.

20.

30.

30.

50.

60.

81.

01.

21.

570

----

--0.

10.

20.

20.

30.

40.

40.

50.

70.

81.

01.

380

----

----

0.1

0.2

0.2

0.3

0.4

0.5

0.6

0.7

0.8

1.0

90--

----

--0.

10.

20.

20.

30.

30.

40.

50.

60.

70.

810

0--

----

----

0.1

0.2

0.2

0.3

0.4

0.4

0.5

0.6

0.7

110

----

----

--0.

10.

20.

20.

30.

30.

40.

50.

50.

650

----

----

--0.

10.

20.

20.

20.

30.

30.

40.

50.

660

----

----

----

0.1

0.2

0.2

0.2

0.3

0.3

0.4

0.5

70--

----

----

----

0.1

0.2

0.2

0.2

0.3

0.3

0.4

80--

----

----

----

--0.

10.

20.

20.

20.

30.

490

----

----

----

----

--0.

10.

20.

20.

20.

310

0--

----

----

----

----

--0.

10.

20.

20.

211

0--

----

----

----

----

--0.

10.

20.

20.

2

11 /4”

11 /2”

CU.F

T. FR

EE A

IR P

ER M

IN. P

ASSI

NG TH

ROUG

H 50

FT. L

ENGT

HS O

F HOS

E20

3040

5060

7080

9010

011

012

013

014

015

0LO

SS O

F PRE

SSUR

E (P

SI) I

N 50

FT. L

ENGT

HS O

F HOS

E

SIZE

OF H

OSE,

GAUG

ECO

UPLE

DPR

ESSU

REEA

CH E

ND, I

N.AT

LINE

, LB.

*For

long

er o

r sho

rter

leng

ths

of h

ose,

the

fric

tion

loss

is p

ropo

rtio

nal t

o th

e le

ngth

, i.e

.: fo

r 25

ft. o

ne-h

alf o

f the

abo

ve; f

or 1

50 ft

., th

ree

tim

es th

e ab

ove,

etc

.

14 15

DECIMAL AND METRICEQUIVALENTS OF COMMON

FRACTIONS OF AN INCH

FRACTION DECIMAL Mm

FRIC

TIO

N L

OS

S O

F A

IR I

N P

IPE

- P

RE

SS

UR

E L

OS

S I

N P

OU

ND

S F

OR

EA

CH

100

FE

ET

OF

ST

RA

IGH

T P

IPE

LINE

PRE

SSUR

E - P

SIG

1015

2030

4050

7510

012

515

020

025

030

035

010

1.45

1.24

.96

.79

.67

.48

.38

.31

.26

.20

.16

.14

.12

152.

682.

081.

701.

431.

04.8

1.6

7.5

7.4

3.3

5.3

0.2

520

3.60

2.94

2.48

1.80

1.41

1.15

.98

.75

.61

.51

.44

305.

403.

903.

052.

502.

121.

631.

321.

11.9

640

6.80

5.31

4.37

3.70

2.84

2.30

1.94

1.67

508.

206.

755.

704.

373.

552.

992.

5860

11.7

9.61

8.16

6.25

5.08

4.27

3.68

8014

.411

.08.

957.

526.

5010

017

.113

.911

.710

.1

10.4

2.3

5.3

0.2

3.1

9.1

6.1

2.3

4.2

8.2

4.1

8.1

5.1

2.1

120

1.57

1.31

1.12

.87

.71

.60

.43

.98

.80

.68

.52

.42

.35

.31

353.

222.

502.

041.

721.

251.

931.

591.

351.

03.8

4.7

1.6

150

4.95

4.05

3.42

2.47

655.

714.

123.

232.

652.

251.

721.

401.

181.

0180

6.19

4.74

3.98

3.37

2.58

2.10

1.76

1.52

100

9.60

7.53

6.40

5.25

4.02

3.26

2.74

2.37

125

11.7

9.70

8.12

6.22

5.05

4.25

3.67

150

12.6

11.5

8.85

7.16

6.03

5.20

200

15.6

12.6

10.6

9.14

250

19.7

16.6

14.3

NOM

INAL

CFM

PIPE

SIZ

EFR

EE A

IR

1 /2”

SCHE

DULE

40 3 /4”

SCHE

DULE

40

1/64 0.01562 0.3971/32 0.03125 0.794

3/64 0.04688 1.1911/16 0.06250 1.588

5/64 0.07812 1.9843/32 0.09375 2.381

7/64 0.10938 2.7781/8 0.12500 3.175

9/64 0.14062 3.5725/32 0.15625 3.969

11/64 0.17188 4.3663/16 0.18750 4.763

13/64 0.20312 5.1597/32 0.21875 5.556

15/64 0.23438 5.9531/4 0.25000 6.350

17/64 0.26562 6.7479/32 0.28125 7.144

19/64 0.29688 7.5415/16 0.31250 7.938

21/64 0.32812 8.33411/32 0.34375 8.731

23/64 0.35938 9.1283/8 0.37500 9.525

25/64 0.39062 9.92213/32 0.40625 10.319

27/64 0.42188 10.7167/16 0.43750 11.113

29/64 0.45312 11.50915/32 0.46875 11.906

31/64 0.48438 12.3031/2 0.50000 12.700

33/64 0.51562 13.09717/32 0.53125 13.494

35/64 0.54688 13.8919/16 0.56250 14.288

37/64 0.57812 14.68419/32 0.59375 15.081

39/64 0.60938 15.4785/8 0.62500 15.875

41/64 0.64062 16.27221/32 0.65625 16.669

43/64 0.67188 17.06611/16 0.68750 17.463

45/64 0.70312 17.85923/32 0.71875 18.256

47/64 0.73438 18.6533/4 0.75000 19.050

49/64 0.76562 19.44725/32 0.78125 19.844

51/64 0.79688 20.24113/16 0.81250 20.638

53/64 0.82812 21.03427/32 0.84375 21.431

55/64 0.85938 21.8287/8 0.87500 22.225

57/64 0.89062 22.62229/32 0.90625 23.019

59/64 0.92188 23.41615/16 0.93750 23.813

61/64 0.95312 24.20931/32 0.96875 24.606

63/64 0.98438 25.0031/1 1.00000 25.400