Module 6

Question 1

a valve used in a pneumatic system to direct the airflow from one place to another to permit the actuating parts to perform their work

Answer 1

Control valve

Question 2

the lowest pressure that will open a valve

Answer 2

Cracking pressure

Question 3

a valve having three primary connections on the outside of the valve body, and three ports inside the valve

Answer 3

Three-way valve

Question 4

a valve with four primary connections and either four or five external ports

Answer 4

Four-way valve

Question 5

a special four-way valve with five external connections, all connected to primary system connections

Answer 5

Five-way valve

Question 6

Name the four methods of identifying control valves.

Answer 6

Number of primary connecting ports
Number of control positions
Type of control element
Method of operation

Question 7

If not properly sized, globe valves can cause _____ flow.

Answer 7

Turbulent

Question 8

A gate valve should not be used for _____ flow.

Answer 8

Throttling or Regulating

Question 9

Needle valves used for regulating flow have high _____ losses.

Answer 9

Pressure

Question 10

The most common method of controlling automatically operated valves is with electric _____.

Answer 10

Solenoids

Question 11

Two-position automatically operated valves are classified as being normally _____ or normally _____.

Answer 11

Open, Closed

Question 12

Large quantities of high pressure air are best controlled by solenoid valves that are _____-operated.

Answer 12

Pilot

Question 13

Check valves are classified as automatic two-way, two-_____ valves.

Answer 13

Position

Question 14

A disadvantage of two-way spool valves is that they are not always _____.

Answer 14

Pressure Balanced

Question 15

Three-way valves have three _____ or working connections.

Answer 15

Primary

Question 16

The most common application of a two-position, three-way valve is in _____ control.

Answer 16

Directional

Question 17

Three-way valves having a blocked center position are usually made to center _____.

Answer 17

Automatically

Question 18

When compressed air completes its work it is usually _____ to the atmosphere.

Answer 18

Exhausted or Vented

Question 19

Four-way valves reduce the total number of _____ in a system.

Answer 19

Controls

Question 20

Airflow in a nonactuated two-position, four-way valve flows in _____ direction(s).

Answer 20

Two

Question 21

The centering of a three-position, four-way valve is usually accomplished by _____.

Answer 21

Springs

Question 22

A manually operated flow control valve may be further identified by all of the following except

a. number of connecting ports
b. number of control positions
c. pressure capacity
d. type of control element

Answer 22

c. Pressure capacity.

Question 23

The lowest pressure that will open a check valve is called the _____ pressure.

Answer 23

Cracking

Question 24

Manually operated stop or isolating valves (globe, gate, or ball) are classed as _____-way valves.

Answer 24

Two

Question 25

A three-way valve is constructed with three _____.

Answer 25

Primary connections

Question 26

The high-pressure losses in a needle valve are caused by the _____.

Answer 26

Valve seat

Question 27

Three-position, three-way valves are usually held in the center position by _____.

Answer 27

Springs

Question 28

What is the most common method of actuating automatically operated flow control valves?

Answer 28

Electric solenoids

Question 29

Compressed air returning through a valve after it has done work is often directed to the _____.

Answer 29

Atmosphere

Question 30

Because a solenoid has limited lifting strength, the valve closing spring in a high-pressure system must be _____ and the valve seat opening _____.

Answer 30

Weak; small

Question 31

In how many directions can air flow in a nonactuated two-position, four-way valve?

Answer 31

Two