Chapter 8 Flashcards
Compressor lubrication may be divided into two main sections __________ lubrication and __________ lubrication.
A) Splash, External, Pressure
B) Internal, External
C) Peripheral, Internal
D) Internal, Splash, External
E) Splash, Pressure
B
In the ____________ compressor, the male rotor has convex lobes and the female rotor has concave flutes.
A) rotary screw
B) free piston
C) lobe type rotary
D) axial flow
E) sliding vanes
A
The rotary screw compressor usually has the _______ by the driver.
A) Concave female lobe driven
B) Convex male lobe driven
C) Male concave flute driven
D) Female and male driven
E) Female concave flute driven
B
Aftercoolers are used to cool air before it is delivered to the:
A) air receiver
B) next compression stage
C) compressor discharge
D) compressor inlet
E) return air system
A
In multistage compression, the high-pressure cylinders are ____________ because the volume is ____________ and the pressure is ____________ than the lower pressure stages.
A) smaller; more; lower
B) larger; more; less
C) smaller; less; higher
D) larger; more; lower
E) larger; lower; less
C
Cylinder arrangements of reciprocating air compressors may be:
A) Vertical, angled, or horizontal
B) Rotary or simplex
C) The V , rotary, or Y type
D) Axial or vertical
E) Twin impeller type
A
Rotary lobe compressors have their elements:
A) Lubricated by oil
B) Enclosed by an aluminum casing
C) Revolving in opposite directions
D) Lubricated by graphite
E) As spring loaded vanes
C
The lobe type compressor runs at speeds up to about __________ rpm.
A) 1550
B) 1750
C) 1600
D) 1700
E) 1650
B
An important advantage of a sliding vane compressor is that it:
A) Has a high starting torque
B) Requires light nylon timing gears
C) Does not require inlet or discharge valves
D) Does not require a prime move
E) Does not require internal lubrication
C
Single-acting compressors having the bottom of the cylinder open to the crankcase will have lubrication provided by a/an:
A) Pressure lubricator
B) Force fed oil pump
C) Splash system
D) Oil ring
E) None of the above
C
Some typical components found in a packaged industrial screw compressor are:
A) air filter, moisture separator, air drier
B) compressor driver, moisture injector, discharge valve
C) inlet valve, cooler, crosshead
D) air filter, inlet valve, stationary blades
E) air filters, after filters, impeller
A
Three different designs of rotary compressors are:
- Sliding vane
- Rotary screw
- Axial flow
- Volute centrifugal
- Rotary lobe
- Diffuser vane centrifugal
A) 1, 3, 5
B) 1, 2, 3
C) 2, 4, 6
D) 1, 2, 5
E) 3, 4, 6
D
Compressor valves are usually automatic and open and close by:
A) A camshaft
B) Action of a poppet valve
C) Operation of an air solenoid valve
D) Movement of the piston covering or uncovering ports
E) A pressure difference
E
When a small amount or no air is being used, the controls of a packaged compressor will change modes to:
A) unload
B) full load
C) modulation
D) start
E) emergency shutdown
A
The type of compressor that is used in a wide variety of services and is typically chosen for high pressure, moderate volume service is:
A) Reciprocating
B) Axial
C) Centrifugal
D) Screw
E) Lobe
A
