Module 5 Flashcards Preview

MT 108 Chapter 4 > Module 5 > Flashcards

Flashcards in Module 5 Deck (31):
1

The minimum pressure at which a component begins to split apart

Bursting presssure

2

Bursting pressure divided by system operation pressure

Safety factor

3

Air at normal atmospheric pressure (14.7 psi)

Free air

4

Piping fixture used to trap and eliminate water in the line

Drain leg

5

Measurement of a curve in tubing, from tubing centerline to the center of the circle

Bend radius

6

Name the three types of compressed-air conductors used in a pneumatic piping system.

Pipe
Tubing
Hose

7

Air should flow through a pipe in a(n) _____ pattern.

Streamlined or Laminar

8

The size of an air line should be selected so only a small _____ drop occurs.

Pressure

9

Name at least four items that affect pressure drop.

Volume of air
Air pressure
Length of pipe
Number of fittings
Number of bends

10

To reduce the distance air travels in a large loop system, _____ air receivers are used.

Auxiliary or Extra

11

The lower the pressure in a pipe, the _____ the pressure losses will be.

Larger

12

Pressure losses through fittings and valves are given in terms of _____ of straight pipe.

Feet (or Lengths)

13

Name the three methods used for connecting pipe in a pneumatic system.

Threading
Welding
Flanging

14

Compressor discharge lines should slope away from the compressor at a rate of ______ in. for every _____ ft.

1, 10

15

NPT, when used for pneumatic systems, seals against air leaks with flank-to-flank contact and _____.

Piping compound

16

When connecting pipes, you must never apply piping compound to the _____.

Thread ends

17

More accurate inside and outside diameters are an advantage of _____.

Metallic tubing

18

Avoid using metallic tubing that has been bent and then _____.

Straightened

19

When an air hose is connected to pneumatic piping, the hose should be one size _____ than the size of the connecting pipe thread.

Larger

20

Hose fittings may be classed as permanent and _____.

Reusable

21

The type of hose coupling that uses a spring-loaded poppet to seal off the outlet when the hose is removed is called a(n) _____ coupling.

Quick-disconnect

22

Turbulent airflow is likely to result from a(n) _____.

Large airflow velocity increase.

23

Which type of threaded fitting is probably the best suited to all but heavy-duty air-line applications?

150 lb malleable iron.

24

The pressure drop between the air receiver and the farthest point of air use should be no more than _____ % of the compressor cutout pressure.

10

25

The rate of downward slope for compressed-air piping used for compressor distribution lines should be _____.

1 in. per 10 ft.

26

Excessive pressure drops occurring in a loop system during peak flow may be avoided by the use of auxiliary _____.

Air receivers and compressors.

27

Long pipe runs should always be _____.

Supported with hangers.

28

How does a change in air pressure in a pipe affect the pressure losses?

Decreased pressure, higher losses.

29

Most nonmetallic tubing can be used for a maximum of _____.

100 psi and 190F

30

The pressure loss through fittings and valves is calculated in terms of _____.

Feet of straight pipe.

31

When disconnecting an air hose, make sure to take all of the following precautions except
a. depressurize the hose
b. have a buddy present
c. use the shutoff valve, if there is one
d. wear eye protection

b. Have a buddy present.