Compressed Air Systems

Front 1

What is the definition of a compressed air system?

Back 1

Pneumatic systems that operate above atmospheric pressure and are used as a source of energy to drive numerous types of equipment

Front 2

What are the typical components of a pneumatic system?

Back 2

Compressors, receiver tanks, filters, pressure regulators, lubricators, mufflers, dryers, actuators, control valves (pressure switches), conductors, drains, and safety relief valves.

Front 3

Where do you want your inlet installed for your compressor system?

Back 3

In a cool shaded place. Cool air is ideal for compression.

Front 4

How much air supply must the receiver tank hold?

Back 4

Enough to prevent a pressure drop of more than 5psi what all service outlets are being used.

Front 5

What should the delta P be on a compressed air system?

Back 5

15psi.

Front 6

What is the most common type of compressor?

Back 6

Belt-driven type.

Front 7

Receivers are usually equip with what to control operation of the compressor in response to pressure drops due to usage?

Back 7

A pressure switch.

Front 8

On smaller systems without aftercoolers, what do they use to cool the air and allow moister to settle out?

Back 8

The receiver.

Front 9

What is best practice for installing piping for a compressor?

Back 9

Fewest bends possible and large enough to minimize pressure drop.

Front 10

What is an air receiver and what codes are enforced for it?

Back 10

An air receiver is a pressure vessel and applicable codes are enforced under the alberta boiler and pressure vessels act.

Front 11

What must a air receiver (pressure vessel) have?

Back 11

A gauge, drain, SRV, and connections to the piping system. Large systems must have a manhole.

Front 12

What does the pressure switch control?

Back 12

The compressor cycle cut-in and cut-out pressures.

Front 13

What should the PRV be set to on the receiver?

Back 13

10 psi above the cut out pressure setting.

Front 14

If shut off valves are required, where does the PRV go?

Back 14

Must be mounted on the compressor side of the shut off valve.

Front 15

Where do you install an automatic moisture trap?

Back 15

On the lowest part of the receiver.

Front 16

Where should the water be discharged from the moisture trap?

Back 16

To a floor drain.

Front 17

What must you never do to suction piping?

Back 17

Reduce it to less than the compressor intake.

Front 18

Where is an oil separator installed and what is it used for?

Back 18

Between the compressor and receiver and are used to prevent lubricants from the compressor from reaching the receiver.

Front 19

What is the role of the aftercooler?

Back 19

To bring the temperature of the compressed air down to ambient temperature.

Front 20

Aftercoolers the same size as the suction piping should be installed where?

Back 20

Between the compressor and receiver, grading towards the receiver.

Front 21

If the length of the aftercooler exceeds 3 meters, what must you do to the suction pipe?

Back 21

Increase it 1 pipe size.

Front 22

What are the two models or aftercoolers?

Back 22

Water-cooled and air-cooled

Front 23

What is the role of the intercooler?

Back 23

Their purpose is to cool the compressor air by 10F between the cylinder stages.

Front 24

Where is the intercooler mounted?

Back 24

Between the cylinders. (Finned pipe)

Front 25

What percentage does the intercooler reduce the average power requirements of a compressor?

Back 25

15%.

Front 26

What is the role of compressor unloaded valves?

Back 26

To limit pressures according to fluctuations in demand. A form of control to prevent over pressure and possible explosions.

Front 27

What type and material should air dryers be?

Back 27

Absorptive type and should be made of silica gel, activated alumina or an equivalent.

Front 28

Where are dryers installed?

Back 28

Downstream of the receiver tank.

Front 29

What can be advisable to install at the immediate upstream of then hose connections?

Back 29

Dust filter.

Front 30

When are oil lubricators sometimes required?

Back 30

For automatic lubrication of pneumatic tools.

Front 31

What is the most common type of compressor for small and medium installations?

Back 31

Piston-type (reciprocating) compressors.

Front 32

What are the ranges on a reciprocating compressor?

Back 32

40cfm to 10,000cfm and 20psi to 30,000psi.

Front 33

What is a variation of reciprocating compressors?

Back 33

Diaphragm compressor.

Front 34

How does a diaphragm compressor work?

Back 34

Has a diaphragm mounted above the cylinder, which prevents contaminants such as compressor lubricants from entering the airstream.

Front 35

Where are diaphragm compressors used?

Back 35

In clean rooms such as hospitals, food processing plants, and medical/pharmaceutical industries. Applications where clean are is essential.

Front 36

What are mechanically actuated diaphragm compressors manufactured for?

Back 36

Low flow rates, moderate pressures and vacuum service.

Front 37

If higher pressures are needed, what type of diaphragm compressor is used?

Back 37

Hydraulic.

Front 38

What are the 2 type of rotary vane compressors?

Back 38

Single vane

Multiple vane

Front 39

What are the two type of flow (dynamic) compressors?

Back 39

Screw (axial) compressors or turbo (centrifugal) compressors.

Front 40

What speeds to flow (dynamic) compressors operate at?

Back 40

In excess of 5000 RPM

Front 41

What is the most popular style of compressor for industrial applications?

Back 41

Screw (axial) compressors.

Front 42

What is the max pressure drop during peak demand on an air distribution system?

Back 42

5psi.

Front 43

What is required on a horizontal distribution piping system?

Back 43

That all pipe is graded in the direction of flow.

Front 44

What pipe can be used in a small distribution system?

Back 44

It may consist of copper (type K or L) that is soldered or brazed.

Front 45

What pipe can be used in a larger air distribution systems.

Back 45

Sched 40 black iron joined with threaded joints for up to 2” and welded joints over 2”.

Front 46

Where should individual service outlets be taken off from?

Back 46

The top of the supply main and should be equip with a drip leg below each air hose connector.

Front 47

To obtain 1 cubic foot of compressed air at 100psig the compressor needs to move:

Back 47

7 cubic feet of air into the suction inlet.

Front 48

Air has the ability to hold how much extra/less moisture for each 20 degree Celsius change in temp?

Back 48

Rise- twice as much

Drop- half as much

Front 49

What is an FRL?

Back 49

A filter,regulator,lubricator is used to get rid of contaminants, adjust pressure, and add or remove oil.

Front 50

Does a FRL have a direction of flow.

Back 50

Yes. You MUST install correctly.

Front 51

At 2000m above sea level, air is approximately how heavy?

Back 51

80% of the volume at sea level.

Front 52

At 2000m, how much more air must be delivered to the compressor suction?

Back 52

30% more.

Front 53

What you should you do to the main line to cover potential expansion?

Back 53

Increase the length with a “little bit extra”

Front 54

What materials are commonly used in compressed air systems, because they are non-corrosive?

Back 54

Plastic, brass, copper, and aluminum.

Front 55

Black pipe is still commonly used because it is low cost, but what is the drawback?

Back 55

Causes rusting and scaling, leading to major system trouble.

Front 56

What is the logical pipe choice for small to medium size systems?

Back 56

Plastic.

Front 57

What is the advantage of plastic coil piping?

Back 57

Can drastically reduce the pressure loses that normally result from using standard pipe fittings and sharp changes of direction.