2B3 - CHAPTER 7 QUESTIONS AND VERIFIED
CORRECT ANSWERS.
B ANSWER : -Which type of rotary compressor requires internal lubrication?
Select one:
a. roots
b. sliding vane
c. roots and sliding vane
d. axial
e. centrifugal
B ANSWER : -How are cylinders of small and medium-sized single acting air compressors usually cooled?
Select one:
a. Water jackets cored in the cylinders.
b. Fins cast on exterior surfaces to facilitate cooling by atmospheric air.
c. Forced air cooling.
d. Separate outer cased water jackets.
e. Placing them outside
A, E ANSWER : -What type(s) of inlet and discharge valves are most commonly used with air
compressors? (you may select more than one type, but each incorrect selection will deduct from your
score)
Select one or more:
a. plate
b. ball
c. flapper
,d. plug
e. channel
D ANSWER : -Rotary air compressors can be divided into the following types:
1. reaction
2. sliding vane
3. roots
4. screw
5. liquid seal
Select one:
a. 1, 2, 3
b. 1, 2, 4
c. 2, 3, 4
d. 2, 3, 4, 5
e. 3, 4, 5
E ANSWER : -When a reciprocating compressor is used to produce a discharge pressure that is above
________ kPa, the compressor will typically have two or more compression stages.
Select one:
a. 50
b. 100
c. 400
d. 550
e. 1000
E ANSWER : -A reduction in heat transfer is usually caused by __________ of water-jacket surfaces
which causes high air compressor discharge temperatures.
, Select one:
a. oxidation
b. pitting
c. heavy water
d. bio-wastes
e. scaling
A ANSWER : -What is the quickest way to spot valve trouble in a two stage air compressor?
Select one:
a. check discharge temperature
b. check intercooler pressure
c. check aftercooler pressure
d. check intercooler temperature
e. sound
B ANSWER : -A straight two-lobe roots rotary compressor is used extensively for:
Select one:
a. low compression.
b. high volume and low compression.
c. high compression.
d. low compression and clean intake.
e. low volume high compression
SA ANSWER : -Final cooling of compressed air at the air compressor discharge is called __________.
Select one:
CORRECT ANSWERS.
B ANSWER : -Which type of rotary compressor requires internal lubrication?
Select one:
a. roots
b. sliding vane
c. roots and sliding vane
d. axial
e. centrifugal
B ANSWER : -How are cylinders of small and medium-sized single acting air compressors usually cooled?
Select one:
a. Water jackets cored in the cylinders.
b. Fins cast on exterior surfaces to facilitate cooling by atmospheric air.
c. Forced air cooling.
d. Separate outer cased water jackets.
e. Placing them outside
A, E ANSWER : -What type(s) of inlet and discharge valves are most commonly used with air
compressors? (you may select more than one type, but each incorrect selection will deduct from your
score)
Select one or more:
a. plate
b. ball
c. flapper
,d. plug
e. channel
D ANSWER : -Rotary air compressors can be divided into the following types:
1. reaction
2. sliding vane
3. roots
4. screw
5. liquid seal
Select one:
a. 1, 2, 3
b. 1, 2, 4
c. 2, 3, 4
d. 2, 3, 4, 5
e. 3, 4, 5
E ANSWER : -When a reciprocating compressor is used to produce a discharge pressure that is above
________ kPa, the compressor will typically have two or more compression stages.
Select one:
a. 50
b. 100
c. 400
d. 550
e. 1000
E ANSWER : -A reduction in heat transfer is usually caused by __________ of water-jacket surfaces
which causes high air compressor discharge temperatures.
, Select one:
a. oxidation
b. pitting
c. heavy water
d. bio-wastes
e. scaling
A ANSWER : -What is the quickest way to spot valve trouble in a two stage air compressor?
Select one:
a. check discharge temperature
b. check intercooler pressure
c. check aftercooler pressure
d. check intercooler temperature
e. sound
B ANSWER : -A straight two-lobe roots rotary compressor is used extensively for:
Select one:
a. low compression.
b. high volume and low compression.
c. high compression.
d. low compression and clean intake.
e. low volume high compression
SA ANSWER : -Final cooling of compressed air at the air compressor discharge is called __________.
Select one:
