01 Compressed Air Fundamentals

Compressed Air Fundamentals

Doosan Infracore - Portable Power

CONFIDENTIAL

Company Confidential

Compressor Fundamentals and Safety

• Compressed Air Basics

• I-R Model Designations

• Terms You Need to Know

• Product and Operator Safety


Compressed Air

• Air is made up of molecules moving continuously in random patterns.

• If molecules are placed in a balloon, they will continuously hit its walls.

• The added effect of all the molecules hitting against the wall of the balloon is called pressure.


Compressed Air

• Molecules inside the balloon hit in all directions, at speeds so high that we can’t notice any change in size

• Outside the balloon there are also molecules hitting the outside wall

• The balloon grows as more molecules are placed into the balloon, making the number of inside hits, larger than the outside.


Compressed Air

• Let’s look at the molecule in the left container……...

• ……..now let’s move the piston down….

• ……the molecule now hits the piston more times…...

• THE PRESSURE HAS INCREASED


Compressed Air

• If we apply heat without moving the piston…...…

• …..the speed of the molecules increases…..

• ….thus increasing the number of hits against the walls…….

• THE PRESSURE HAS INCREASED


The compression of gases follows the laws of physics:

V1 x P1 = V2 x P2

T1 T2

V= Volume, P= Pressure, T= Temperature

Compressed Air


Compressor Basics

There are two basic ways to push air molecules:

- Reciprocating Movement

- Piston and Cylinder

- Rotary Movement

- Fan Blades

- Screws

- Centrifugal Rotors


ADMISSION

DISCHARGE

COMPRESSION

Compressor Basics


Compressor Basics

• The compressor airend is a fixed displacement pump which uses a pair of helical rotors to compress the air.

• As the rotors turn faster more air is sucked into the airend.

• The amount of air that is sucked into the airend is measured in cubic feet per minute. This is the compressor input rating -- CFM


Compressor Basics

• As the air travels through the airend it is compressed between the rotors. This increases the pressure (PSIG) of the air.

• The air exits the airend when the rated pressure is achieved; e.g., 100, 125, 150 psig. This is the compressor output rating --PSIG!


Compressed Air

• When air molecules move in a particular direction, we can measure the volume of air (Cubic Feet) that carries these molecules.

• If measure is taken during one minute, we can then express the velocity of this volume in Cubic Feet per Minute.


Compressor Basics

• The work required to compress a given amount of air (cubic foot) in a specific amount of time (minute) to a specified pressure (psig) is measured in horsepower.

OneCubicFoot

1.0 Cu. Ft. =0.128 Cu.Ft. @ 100 psig(7:1 ratio)

185 ICFM = 23.7 ACFM @ 100 PSIG


Compressor Basics

• For a given amount of horsepower you can attain many different compressor ratings.

- For example, with a 100 bhp engine the following are a few of the possible airflow/pressure (cfm/psig) combinations:

400/80

375/100

325/125

300/150


Compressor Basics

Compressor Power

Airflow (CFM)

Pow

er (B

HP)

Engine Power Rating

X Y Z


Compressor Basics

• Engines are rated to produce a certain amount of horsepower at a specific speed (rpm). As you reduce the speed you (generally) reduce the horsepower output of the engine. Since rotor speed is dependent on engine speed…...

…air flow relates to engine speed !


Compressed Air

• If we move the balloon to a higher altitude, the size of the balloon will increase, why?


Effect of Altitude

Sea level(more molecules per cubic foot)

High altitude(less molecules per cubic foot)


Effect of Altitude and Temperature

ALT. FTS 0 1000 2000 3000 4000 5000 6000 7000 8000 12000 15000

TEMP MTS 0 304.8 609.6 914.4 1219.2 1524 1828.8 2133.6 2438.4 3657.6 4572

0F 0C

-40 -40 0.805 0.835 0.866 0.898 0.932 0.963 1.004 1.043 1.084 1.266 1.426

-20 -28.9 0.843 0.875 0.907 0.941 0.976 1.009 1.052 1.093 1.136 1.326 1.494

0 -17.8 0.882 0.915 0.949 0.984 1.021 1.055 1.100 1.142 1.187 1.387 1.562

20 -6.7 0.920 0.954 0.990 1.026 1.065 1.101 1.148 1.192 1.239 1.447 1.630

40 4.4 0.958 0.994 1.031 1.069 1.110 1.147 1.196 1.242 1.291 1.507 1.698

60 15.6 0.997 1.034 1.072 1.112 1.154 1.193 1.243 1.292 1.342 1.568 1.766

80 26.7 1.035 1.074 1.114 1.155 1.199 1.239 1.291 1.341 1.394 1.628 1.834

100 37.8 1.074 1.114 1.155 1.198 1.243 1.284 1.339 1.391 1.446 1.689 1.902

120 48.9 1.112 1.154 1.196 1.241 1.288 1.330 1.387 1.441 1.498 1.749 1.970

SCFM x FACTOR = ACFM at altitude and temperature


Compressor Basics

• Because there are less air molecules per CFM at higher altitude, horsepower required by the air end decreases with altitude.

• When engines run at high altitude, there are less air molecules available for the combustion so it is less efficient. Total engine horsepower output decreases.

• The altitude rating of a compressor is at the point where engine HP output and airend HP requirement are the same.


Compressor Basics - Altitude Rating

020406080

100120

1000 2000 3000 4000 5000 6000 7000

Altitude

Pow

er

Engine Air End

Airend HP demand

Engine HP output


Pressure Loss

LINE PRESSURE (PSIG)DIA LGT CFM 60 80 100 120 150 200 300

¾” 50’ 120 9.0 7.4 6.3 5.1 3.9 2.7140 12.0 9.9 8.4 6.9 5.3 3.6160 12.7 10.8 8.9 6.8 4.6180 13.6 11.1 8.5 5.8200 16.6 13.5 10.4 7.1220 16.2 12.4 8.4

1” 50’ 120 2.7 2.1150 4.1 3.2 2.7 2.3180 5.8 4.6 3.8 3.2 2.6 2.0 1.4210 7.7 6.1 4.0 4.3 3.5 2.7 1.8240 7.9 6.5 5.5 4.5 3.5 2.4


Effect of Moisture in the Air

• All ambient air contains moisture.

• Moisture concentration is low at compressor intake.

• Moisture concentration is high at compressor outlet.

• Volume of air is reduced by compression, but the amount of moisture remains the same.

Result: More moisture per volume of compressed air at the compressor outlet


Effect of Moisture in the Air


Air Compressor

AirCompressor

Ambient Air

1600 ICFM70° F0 PSIG

14.5 PSIA60% RH8.29 GPH

203 ACFM190° F100 PSIG114.5 PSIA100 % RH8.29 GPH

Reference Moisture in the Air Tables.

(These figures are based on 1600 cfm at 100 psig)


Aftercooler

Cooler

WaterSeparator

203 ACFM190° F

100 PSIG114.5 PSIA

8.3 GPH

Ambient air temp = 70° F

203 ACFM85° F

95 PSIG8.3 GPH

203 ACFM84° F

92 PSIG3.9 GPH

4.4 GPH• Condenses and removes moisture


Compressor Basics

Contamination

• Dirt Atmospheric dirt, pipeline dirt, rust, scale

• Oil Oil Aerosol & Oil Vapor

• Water Water Aerosol & Water Vapor

- Compounding the water problem: heat of compression for oil-flooded, screw compressor is 180 - 200ºF; dry screw is 350 - 390ºF


Filters - Condition Air

Coalescing Filter Particulate Filters

203 ACFM84° F

92 PSIG3.9 GPH

203 ACFM82° F

86 PSIG3.3 GPH

203 ACFM83° F

89 PSIG3.5 GPH



• Compressor Basics





Portable Products

• Product Nomenclature

- Compressors

- Light Towers

- Air Dryers and Accessories


Product Nomenclature

Model Designations: PressureP185WIR / XP750WJD / HP915WCU /VHP400WCU / XHP900SCAT

P = 100 - 124 PSIG [100]XP = 125 - 149 PSIG [125]HP = 150 - 174 PSIG [150]

MHP=175 - 199 PSIG

VHP = 200 - 249 PSIG [200]XHP = 250 + PSIG [300 / 350]



Model Designations: CFM

P185WIR / XP750WJD / HP915WCU /VHP400WCU / XHP900SCAT

Portable Air Compressors



Model Designations: PackagingP185WIR / XP750WJD / HP915WCU /VHP400WCU / XHP900SCAT

W = Whisperized (Meets US EPA Noise Code)

S = Non-Whisperized



Model Designations: EngineP185WIR / XP750WJD / HP915WCU /VHP400WCU / XHP900SCA

CA = CaterpillarCU = CumminsIR = Ingersoll-RandJD = John Deere

Portable Air Compressors



Model Designations:

L6-4TH / L8-6HPS

L = Light Tower6 / 8 = Generator Capacity (kW)4 / 6 = Number of LampsHPS = High Pressure SodiumMH = Metal HalideTH = Tungsten Halogen

Portable Light Towers



Model Designations:

A-165 / AD-85 / AF-1600 / RD1000

A = Air Aftercooler

R = Regenerative D = Air DryerF = Air Filter85 / 165 / 1600 = Capacity

Air Dryers & Accessory Equipment



• Compressor Basics





Terms You Need to Know

LAT gph B10 Atmosphere

3 phase PSI Lumen DF2

Unload LRG ACFM micron

µ CFM Foot Candle Dew Point

MinimumPressure

Skid Approach psig

Sub-base SCFM Cool Box PSIA CO

01 Compressed Air Fundamentals

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