Valves

Question 1

The function of valves is to alter, generate and cancel signals for?

Answer 1

Sensing
Processing
Controlling
Supplying working air

Question 2

What are the 4 main types of valves ?

Answer 2

Non return valves
Directional control valves
Pressure control valves
Flow control valves

Question 3

What is the purpose and 2 main configurations of the non return valve?

Answer 3

Allow flow in one direction

With a spring return
Without a spring return

Question 4

What are the 4 types of non Return valves?

Answer 4

Shuttle valve or GATE
Two pressure valve AND GATE
Quick exhaust valve
Time delay valve

Question 5

What is the purpose of a pilot operated NRV de lockable?

Answer 5

Operate in both directions as and when required

Question 6

What is cracking pressure?

Answer 6

Is the point at when air pressure overcomes spring pressure of the spring

Question 7

What is the purpose of a shuttle valve?

Answer 7

Used to select two inputs, if two inputs are applied at the same time the ball valve is moved by the higher pressure to close off the lower input pressure

OUTPUT PRESSURE WILL BE HIGHER OF THE TWO INPUTS

Question 8

How does a two pressure valve operate?

Answer 8

The highest input pressure will hold the valve across allowing the lower pressure through to the output port

Question 9

What is the purpose of a quick exhaust valve?

Answer 9

Designed to quickly exhaust pneumatic cylinders

Question 10

What are the 3 components of a time delay valve ?

Answer 10

Receiver
One way flow control valve
3/2 DCV, pilot actuated

Question 11

What does the number of squares Indicate on a DCV?

Answer 11

Switch positions

Question 12

What do the lines indicate on a DCV?

Answer 12

Flow paths

Question 13

What do the arrows indicate on a DCV?

Answer 13

Direction of flow

Question 14

What are the 4 methods of valve actuation?

Answer 14

Mechanically
Manually
Pilot
Electronically

Question 15

What number is the supply labelled?

Answer 15

1

Question 16

What number is the outputs labelled?

Answer 16

2,4

Question 17

What number is the exhausts labelled?

Answer 17

3,5

Question 18

What number is the signals labelled?

Answer 18

12,14

Question 19

What are the 2 types of pressure relief valves?

Answer 19

Pressure regulating

Pressure relief

Question 20

What is the position when it’s a pressure relief valve?

Answer 20

Always closed

Question 21

What is the position when it’s a pressure regulator?

Answer 21

Always open

Question 22

What do pressure regulators ensure?

Answer 22

Operating pressures at various points remain at a constant pressure regardless of the consumption

Question 23

How does a pressure regulator operate?

Answer 23

As outlet increases, this pressure acts on a spring with overcomes spring pressure at a set pressure.

This then closes the valve and allows pressure to drop , it then falls back when the pressure is back to sufficient levels

Question 24

What is the purpose of a pressure relief valve?

Answer 24

Controls or limits the pressure in a system or vessel

Question 25

How does a pressure relief valve work?

Answer 25

As air pressure rises it acts on a spring which overcomes the cracking pressure , this then allows the valve to open and pressure to leave

Question 26

What must a pressure relief valve be capable of doing?

Answer 26

Safety valve - must be capable of discharging more air than the system can supply

Question 27

What is the flow control valve?

Answer 27

Controls the amount of fluid that is allowed to pass through them?

Question 28

What are the 2 types of flow rates?

Answer 28

Fixed (restrictor)

Adjustable (throttle)

Question 29

What are the 2 basic method that are used to control valves?

Answer 29

Supply air throttling

Exhaust air throttling