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PNEUMATICS PRACTICE QUESTIONS These questions have been taken from official syllabus PYP-004 and contribute to the preparation for Theory Tests and also for Final Examination

2014

M.B. Ahmed Lecturer, CASS (Mechanical) KFUPM

1/12/2014

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Lectures Plan

First Lecture Objectives

Introduction to Pneumatics, its application, Advantages and Disadvantages

Components of Pneumatics System

Actuators: Single & Double Acting Cylinders

Pneumatic Valves: 3/2 Valves and 5-Port Valve

Practical Exercise: 01 and 02 in the book

Second Lecture Objectives

Concept and Function of Pilot & Roller Valves

Concept and Function of Dual Pressure and Shuttle Valves

Practical Exercises: 03, 04 and 05 in the book

Use of Fluid Sim Software in the Lab

Third Lecture Objectives

Exercise: 06

Assessment

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INSTRUCTIONS:

These questions are lecture-wise arranged. Students should attempt the questions under

LECTURE ONE heading after first week and so on.

In the end there are solved exercises.

All the questions in this file are important for Theory Test and also helpful for Final Exam

LECTURE ONE

1. A pressure regulator is positioned ____ a Air Reservoir

a. Before

b. After

2. Compressed air has a minimal risk of fire or explosion

a. True

b. False

3. 1 bar is equal to ________

a. 10 N/M OR 100000 N/M

b. 200 psi

c. 1000 NM

4. The difference between single acting and double acting cylinders is:

a. Single acting cylinders are smaller than Double acting cylinders

b. Double acting cylinders have two pistons

c. Work can be done in two directions in double acting cylinder unlike single acting

cylinders.

5. This schematic diagram is called -----

a. 3/2 normally Closed valve

b. 3/2 normally Open valve

c. Pilot Valve

6. Compressed air enters to the cylinder through ___.

a. Intake Manifold

b. Filter

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c. Lubricator

d. Valve

7. The advantage of using a _______ cylinder is the ability to control the return movement along with the forward motion by flow control valve.

a. Single Acting Cylinder

b. Double Acting Cylinder

8. _____ is a device that takes energy and converts into motion.

a. Actuator

b. Valve

c. Compressor

9. _______are mechanical devices that employ energy created by electricity, air or

liquid and convert into linear motion

a. Actuators

b. Valves

c. Compressors

10. A clean compressed air is supplied to actuators and valves through______

a. Intake Manifold

b. Air Service Unit

c. Compressor

11. _________ is a device that provides oil between sliding parts for easy movement

a. Filter

b. Lubricator

c. Oil Pump

12. An air service unit consists of ______, water separator, lubricator, pressure

regulator and pressure gauge

a. Filter

b. Oil Pump

c. Pressure Switch

13. The air is passed through the _______ before entering the valve and actuators.

a. Air Service Unit

b. Compressor

c. Double Acting Cylinders

14. ______ is a mechanical device containing a reciprocating pump and electrical

motor

a. Air Service Unit

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b. Actuator

c. Compressor

15. In Compressor air is drawn from the atmosphere using the _____ and is then

compressed by a reciprocating pump

a. Intake Manifold

b. Suction Manifold

c. Pressure Switch

d. Electric Motor

16. The ______ working fluid is incompressible, leading to a minimum of spring action

a. Pneumatic

b. Hydraulic

17. Both pneumatics and hydraulics are applications of _____ power

a. Solar

b. Nuclear

c. Fluid

18. Most industrial pneumatic applications use pressures of about ____pounds per

square inch

a. 550 to 690 Psi

b. 80 to 100 Psi

c. 110 to 150 Psi

19. When the pressurized air is at ____the atmospheric pressure, it becomes

compressed air

a. Less than

b. Equal to

c. Greater than

20. In a ________ acting cylinder both expansion and contraction movements of

cylinder are pneumatically controlled.

a. Double

b. Single

21. The following symbol represents the air flow pattern when:

a. 3-port valve is pressed on

b. When 5-port valve is in normal position

c. When An-gate receives air-signal

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22. Name the following components identifying the symbols.

1

2

3

4

5

6.

7.

8.

9.

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23. Industrial Pneumatic Applications use pressures of about______

a. 80-100 pounds per square inch

b. 550-690 Kpa

c. Both a and B are correct

24. Which of the following is not a part of Air Service Unit

a. Filter

b. Water Separator

c. Lubricator

d. Intake Manifold

25. The device which takes energy and convert into motion is called:

a. Actuator

b. Energy convertor

c. Compressor

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26. In a pneumatic system, energy delivered by a compressor is not generally used

immediately, but is stored as potential energy in ________in the form of

compressed air.

a. Regulator

b. Air Reservoir

c. Pneumatic Valve

27. A cylinder in which air pressure is applied to the piston in only one direction is

called________

a. Double Acting Cylinder

b. Single Acting Cylinder

28. ____ working speeds can be obtained using compressed air.

a. Low

b. High

29. The limitation of Pneumatic System is up to _____

a. 10 bar b. 3 bar c. 7 bar

30. In a Manufacturing Company, the application of Pneumatic System is likely to be

found at ___

a. In Managers Office

b. In Safety Stock Warehouse

c. At Production Lines

31. The name of apparatus used in Pneumatics Lab is:

a. Mitsubishi Equipment

b. Festo Equipment

c. Samsung Equipment

32. It is always possible to obtain uniform and constant speeds with compressed air.

a. True

b. False

33. In Pneumatics Lab, Major cause of accident is:

a. Detached air lines

b. Exceeding the permissible working pressure

c. Not wearing the shoes

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34. The main advantage of Pneumatic Systems is:

a. Machines are over- load Safe

b. Compressed air has minimal risk of explosion

c. Long operating Lives

d. All of Above

35. _____ is a device that controls actuator motion

a. Valve

b. Cylinder

c. Intake Manifold

36. The cylinder takes compressed air and coverts it in _____.

a. Reciprocating Motion

b. Rotary Motion

37. Pneumatic Systems tend to have ____ operating lives and require very little

maintenance

a. Long

b. Short

c. Medium

38. Psi stands for pounds per square inch

a. True

b. False

39. Hydraulic Systems are capable of moving higher loads because

a. These systems are made of steel

b. These systems use incompressible working fluid

40. The pressure change between compressor and air receiver is detected by:

a. Pressure Regulator

b. Pressure Switch

c. Pressure Gauge

41. Which one is a Pneumatic System?

a. air brakes on a truck

b. bicycle brakes

c. fuel pump of a car

d. headlights of an automotive

42. A lubricator is used to

a. is adjusted to obtain correct pressure

b. cleans the air

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c. lubricates pneumatic system

d. stores the air

43. A 3/2 valve has

a. 1.5 ports

b. 3 ports and 2 directions

c. 3 directions and 2 ports

d. 5 ports and 2 directions

44. A double acting cylinder has

a. has only one port

b. has a return spring

c. has no return spring

d. has two return springs

45. The advantages of pneumatics system

a. is colorful

b. expensive

c. cannot be used in clean environments

d. overload safe

46. Why is a pressure regulator used in air service unit?

a. to store air

b. to lubricate air

c. to clean air

d. none of the above

47. Air filter is used for

a. adjusting air pressure

b. removing dust particles from the air

c. lubricating the air

d. compressing the air

48. A single-acting cylinder can

a. produce work only in one direction

b. produce work in both directions

c. can produce work in three directions

d. cant produce work

49. Pneumatics is concerned with a system that uses:

a. Oil

b. Expanded air

c. Compressed air

d. Electricity

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50. Atmospheric air is compressed by a ------------

a. Pump

b. Compressor

c. Rotary expander

d. Balloon

51. Which of the following controls actuator motion?

a. Single acting cylinder

b. Valve

c. Pressure Regulator

52. A compressed air receiver contains compressed air, which stores:

a. Potential energy

b. Kinetic energy

c. Nuclear energy

53. Which of the following is not a Pneumatic System?

a. Fuel pump b. Air Balloon c. Compressor

LECTURE TWO

54. Which of the following valve is actuated by cylinder-touch?

a. Pilot Valve

b. And Gate

c. Shuttle

d. Roller Valve

55. 5-Port valves can be classed Normally Open and Normally Closed valves

a. True

b. False

56. One-four and One-two ports are found on :

a. Selector Switch

b. Roller Valve

c. Pilot Valve

d. Shuttle Valve

57. The _______ valve is used where the system is stopped by any one mistake.

And Gate

a. Shuttle

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b. Dual Pressure

c. Pilot

58. This Schematic diagram is used to show ----------------valve

a. Shuttle

b. Dual

c. OR gate

d. Both a and c

59. ----- Valve works on principle of pneumatic signals.

a. 5/2 valve

b. Roller valve

c. pilot valve

60. Pilot Valves are_____ port valve

a. 3

b. 5

c. 2

61. The pilot valve is operated by____

a. Spring

b. Pneumatic Signal

c. Manual Switch

62. To get automatic movement of cylinder ______- valve is used.

a. Pilot Valve

b. 3/2 push button

c. Roller Valve

63. To avoid the accidental operation of one control, _______- valves are commonly

used as safety precautions.

a. OR gate

b. Shuttle Valve

c. AND gate

64. The schematic diagram represents

a. a time delay valve

b. a shuttle valve

c. a dual-pressure valve

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d. an h valve

65. The schematic diagram represents

a. a shuttle valve

b. a dual pressure valve

c. an nrv valve

d. a time delay valve

66. Two push-button valves are connected to a dual-pressure valve.

The dual-pressure valve allows the actuator to be controlled when:

a. one-push button is pressed after the other push-button is released

b. both push-buttons are pressed

c. one push-button is released after the other push-button is pressed

d. only one push-button is pressed

67. Another description for a dual-pressure valve is:

a. an or gate

b. an and gate

c. a not valve

d. an exclusive nor valve

68. In the Pneumatically operated 5/2 pilot valve, the numbers 12 & 14 denote:

a. Signal ports b. power supply c. Air supply

69. The adjacent schematic diagram shows:

a. Manual actuation via lever with detent

b. Roller actuated

c. Push button actuated

70. Memorize the symbols for the final exam.

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