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Flashcards in RACT unit 23 Deck (85)
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1

Using two compressors can lower the ________ temperature and increases efficiency

discharge

2

______ refrigerant passes through the suction valve of the compressor to fill the cylinders

cool

3

Reciprocating compressors are used most frequently in _____ and _____ sized commercial refrigeration systems

small and medium

4

The screw compressor is used in ______ commercial and _______ systems

large commercial and industrial systems

5

The rotary, the scroll, along with the reciprocating compressors are used in ________ and light commercial air conditioning

residential

6

Centrifugal compressors are used extensively for ___________ in large buildings

air-conditioning

7

A hermetic reciprocating compressor has a __________ mechanism. The same shaft drives the compressor and motor

direct drive

8

Difference between hermetic and semi hermetic

hermetic is welded and semi-hermetic is serviceable

9

What is the only way to service a hermetic compressor?

cutting open the shell

10

hermetic compressors usually have a _____________ system but smaller hermetics are splash lubricated

pressure lubrication

11

semi hermetic compressors are ______ together so that it is easier to service and repair

bolted

12

smaller semi hermitic compressor use _______ lubrication

splash type

13

larger semi hermetic compressors use ________ lubrication

pressure

14

Motor and crankshaft are connected in a semi hermetic compressor although the ________ is usually horizontal

crankshaft

15

Open drive compressors are manufactured in two styles; ______ drive and ______ drive

belt driven and direct drive

16

Any compressor with the drive on the outside of the casting must have a ____ _____ to keep the refrigerant from escaping

shaft seal

17

In belt drive compressors the compressor and motor shaft are _______

parallel

18

direct drive compressors have a coupling between the shafts, shafts must be in very good __________ to run correctly

alignment

19

rotary screw compressor has an open _____

motor

20

In a screw compressor, a ______ seal traps refrigerant in the compressor housing where the rotating shaft leaves the housing

shaft

21

Screw compressors are used in ______ systems

large

22

The ________ of a reciprocating compressor transmits the circular motion of the rods into a back-and-forth motion for the pistons

crankshaft

23

Crankshafts are normally manufactured or _____ iron or _____

cast iron or steel

24

The off-centre shafts normally have _____ main bearing surfaces. One is on the _____ end and the other on the other end

two

motor

25

some reciprocating compressor crankshafts are straight and have a cam-type arrangement called an ________

eccentric

26

All reciprocating compressor shafts must be ________

lubricated

27

Smaller reciprocating compressors using the splash system may have a ______ basin to catch oil and

catch

28

In a reciprocating compressor, when the compressor runs the oil is then slung to the outside of the __________ surface

crankshaft

29

some crankshafts are _________ and lubricated by a pressure lubrication system

drilled

30

(Recip) Connecting rods connect the ________ to the ______

crankshaft to the piston