absolute discharge / by absolute suction = compression ratio
absolute = psiga 14.7
Which of the following terminal combinations would show an open circuit if the internal overload device in a hermetic compressor should open due to excessive heat.
common to run 1 to 2
common to start 1 to 3
The clearance volume of a compressor cylinder is the
volume of the space between the bottom of the valve plate and the top of the piston at top dead center
The pulley on the motor is called the
drive pulley
The pulley on compressor is called the
driven pulley
If the compression ratio of a system with a reciprocating compressor increases, the amount of refrigerant pumped by the compressor
will decrease
If the compression ratio of a system with a reciprocating compressor decreases, the amount of refrigerant pumped by the compressor
will increase
On a direct drive compressor the ________ is used to connect the compressor shaft and motor shaft together
flexible coupling
Over heated oil may turn to carbon and create ______ in the system
acid
rotary compressors are used primarily in ______.
domestic refrigerators
The discus valve design is more efficient than a flapper valve design because ________.
it allows a compressor designed with less clearance volume
flapper and read valves are use in the ______ compressor
reciprocating
What could happen if a semi-hermetic compressor is operated with the suction service valve back seated and the discharge front seated
the head of the compressor may blow off
The shaft seal on open drive compressor _______.
keeps the refrigerant vapor in and atmosphere out of the compressor
Liquid entering the compression chamber of the reciprocating compressor can lead to ________
damaged piston rings
damaged valves
Connecting rods connect to _______
crankshaft to the piston
On a direct drive compressor the _______ is used to insure proper aliment in a flexible coupling
dial indicator
The ______ valves in a reciprocating compressor opens and closes depending on the difference in pressure across them
suction and discharge
The screw type compressor is used primarily in ________.
large industrial refrigeration and aircondishing systems
Because a scroll compressor has fewer moving parts, it operates much quieter then other compressor designs and technologies
true /false
true
The semi hermetic is one type of reciprocating compressor
true / false
true
The scroll compressor is one type of reciprocating compressor
true /false
false
Scroll compressors are becoming popular because they can handle some liquid flood back with out compressor damage
true / false
true
We use two stage compression on a system that would have a compression ratio that exceeds 8.5 : 1 ratio
true / false
false
exceeds 10:1
A bolted together motor compressor assembly are referred to as a hermetic type
true/ false
false
semi-hermetic
On a belt drive compressor the driven pulley is attached to the compressor
true /false
true
Author
salvatorefricano
ID
295522
Card Set
compressors chapter 23
Description
function of compressor different types of compressors