Sample Exam Questions

Question 1

How do you increase pressure?

Answer 1

Decrease the volume

Question 2

What is the best vacuum pump?

Answer 2

Rotary vane multi-stage

Question 3

What is the most cost efficient compressor?

Answer 3

two stage, double acting

Question 4

What are 4 ways of maximizing pressure control?

Answer 4

1. Unloading devices (fingers)
2. Throttling the air intake
3. Using a variable speed drive
4. Using a pressure switch

Question 5

How do you decrease air slip?

Answer 5

Increase RPM of rotors

Question 6

Where is a water trap placed?

Answer 6

Anywhere the air is cooled below the dew point

Question 7

Where do you put after coolers?

Answer 7

After it leaves the compressor and before it enters the receiver

Question 8

What should you do before disassembly?

Answer 8

ensure that timing gears have matching mate marks beforehand

Question 9

What is the function of intercoolers?

Answer 9

Used to cool the air between stages

Question 10

What are after coolers for?

Answer 10

Heat exchangers which cool the air after it leaves the compressor and before it enters the receiver

Question 11

What are the four types of air dryers?

Answer 11

1. Deliquescent
2. Regenerative desiccant
3. Refrigeration
4. Membrane

Question 12

What are the two types of lubricators?

Answer 12

1. fog lubricators (short dis)
2. Mist lubricators (long dis)

Question 13

Pressure is controlled in the compressor by __________

Answer 13

unloading

Question 14

Pneumatic DCVs can be either rotary or _____types

Answer 14

spool

Question 15

Pneumatic compressors are used to compress atmospheric air reducing its ________ and increasing its ______________

Answer 15

Pneumatic compressors are used to compress atmospheric air reducing its volume and increasing its pressure

Question 16

What is the measurement of a perfect vacuum?

Answer 16

0 bar or 0 psiA

Question 17

Which direction dos air flow?

Answer 17

From high to low pressure areas

Question 18

What is Boyle’s Law?

Answer 18

At constant temperature, absolute pressure (P) varies inversely to the volume (V)

Question 19

What is Charles’s Law?

Answer 19

At a constant volume, a gas varies proportionately to its absolute temperature (T)

Question 20

What is the ideal gas law?

Answer 20

P1xV1/T1 = P2xV2/T2

Question 21

The best pump is ___________

Answer 21

rotary vane (multi-stage)

Question 22

The worst pump is __________

Answer 22

centifugal (regenerative peripheral)

Question 23

What are the two classifications of compressors?

Answer 23

Dynamic and positive displacment

Question 24

__________________ DCV’s permit very little control as they are either wide open or off.

Answer 24

solenoid controlled

Question 25

When a cylinder is required to return rapidly, a _____________ is installed in the retract line of the cyliner

Answer 25

quick exhaust valve

Question 26

What are the 3 most common systems?

Answer 26

1. Grid
2. Decentralized
3. Loop

Question 27

How do permanent pneumatic lines deal with moisture?

Answer 27

They are installed in such a way that any moisture accumulating in the line flows toward a drain

Question 28

What are 4 ways of controlling maximum-pressure?

Answer 28

1. Unloading devices
2. Throttling the air intake
3. Using variable speed drive
4. using a pressure switch to start or stop