If there is a shut-off valve between the aftercooler and the receiver, the aftercooler must be fitted with a?

If there is a shut-off valve between the aftercooler and the receiver, the aftercooler must be fitted with a?

a. safety valve
b. pressure gage
c. thermometer
d. all of the above




Answer: A

Intercoolers should be provided with what on the cooling water side?

Intercoolers should be provided with what on the cooling water side?

a. safety valve
b. pressure gage
c. thermometer
d. all of the above




Answer: C

Reasons for cooling of air in a compressor is?

Reasons for cooling of air in a compressor is?

a. Remove water vapour
b. Remove oil vapour
c. Make cylinder lubrication more effective
d. All of the above
e. A and B





Answer: D

The use of an intercooler to cool the air between stages of compression will reduce the power required for compression by around __ %.

The use of an intercooler to cool the air between stages of compression will reduce the power required for compression by around __ %.

a. 5
b. 10
c. 15
d. 20
e. 25





Answer: C

Which compressor has moving blades attached to the rotor, alternating with fixed blades attached to the casing?

Which compressor has moving blades attached to the rotor, alternating with fixed blades attached to the casing?

a) rotary lobe units
b) screw units
c) sliding vane units
d) axial flow units
e) centrifugal units






Answer: D

Disadvantage of centrifugal compressor is?

Disadvantage of centrifugal compressor is?

a. High maintenance requirements
b. Oil in the air
c. Efficiency is lower than positive displacement compressor
d. Not suited for low capacity work
e. C and D





Answer: E

The rotary screw compressor uses multistage designs when the pressure is above ___ kpa.

The rotary screw compressor uses multistage designs when the pressure is above ___ kpa.

a. 400
b. 300
c. 200
d. 100
e. 800






Answer: A

The rotary screw compressor is suitable for high speeds ranging from __ to __ r/min.

The rotary screw compressor is suitable for high speeds ranging from __ to __ r/min.

a. 5000, 15 000
b. 1000, 10 000
c. 3000, 12 000
d. 2000, 11 000
e. 6000, 17 000






Answer: C

Which compressor features two intermeshing rotors contained within a close fitting casing?

Which compressor features two intermeshing rotors contained within a close fitting casing?

a) rotary lobe units
b) screw units
c) sliding vane units
d) reciprocating units
e) centrifugal units




Answer: B

Rotary lobe compressor single-stage pressure is __ kPa and __ kPa for two-stage.

Rotary lobe compressor single-stage pressure is __ kPa and __ kPa for two-stage.

a. 200, 300
b. 100, 200
c. 50, 100
d. 300, 400
e. 10, 50






Answer: B

Rotary lobe compressor runs at speeds of __ r/min:

Rotary lobe compressor runs at speeds of __ r/min:

a. 1200
b. 1450
c. 1750
d. 1320
e. 1550






Answer: C

Which compressor has two figure-eight shaped impellers revolving in opposite directions within a casing?

Which compressor has two figure-eight shaped impellers revolving in opposite directions within a casing?

a) rotary lobe units
b) screw units
c) sliding vane units
d) reciprocating units
e) centrifugal units




Answer: A

The sliding vane compressor disadvantages are?

The sliding vane compressor disadvantages are?

a. less efficient than the reciprocating compressor
b. higher first cost
c. poor flow of air
d. high starting torque requirements
e. requires inlet and discharge vavles






Answer: A

Which compressor must have intake and discharge valves to control the flow of air entering and leaving?

Which compressor must have intake and discharge valves to control the flow of air entering and leaving?

a) rotary lobe units
b) screw units
c) sliding vane units
d) reciprocating units
e) centrifugal units






Answer: D

Which compressors are dynamic type?

Which compressors are dynamic type?

a) rotary lobe units
b) centrifugal units
c) axial flow units
d) All of the above
e) B and C




Answer: E

Air receivers

Air receivers

a) must have a gage glass
b) must have a thermometer
c) must have a high pressure alarm
d) must have a safety valve
e) must have a high water alarm




Answer: D

An air receiver used in an air compression, system will perform the following functions: 1. act as a storage vessel 2. eliminates pulsation in discharge lines 3. will separate out water from the air 4. controls the temperature of the air before it enters the system

An air receiver used in an air compression, system will perform the following functions:
1. act as a storage vessel
2. eliminates pulsation in discharge lines
3. will separate out water from the air
4. controls the temperature of the air before it enters the system

a) 1, 2
b) 1, 2, 3
c) 1, 2, 4
d) 2, 3, 4
e) 3, 4






Answer: B

Where pistons move in a cylinder it is necessary for the lubricant to provide

Where pistons move in a cylinder it is necessary for the lubricant to provide

a) tension
b) sealing
c) alignment
d) shock reduction
e) vapour venting






Answer: B

The valves on a reciprocating compressor are opened by

The valves on a reciprocating compressor are opened by

a) a pressure difference
b) the cam shaft
c) the eccentric
d) hydraulic pressure
e) a timing gear

Answer: A

Relative to a dry-pipe fire system, an automatic air supply shall be connected so that proper pressure can be maintained in each system, is a statement of the

Relative to a dry-pipe fire system, an automatic air supply shall be connected so that proper pressure can be maintained in each system, is a statement of the

a) National Fire Protection Association Code
b) Industrial Accident Prevention Association
c) Canadian Standards Association
d) Occupational Health and Safety
e) Society of Municipal Fire Marshalls




Answer: A