This document provides an overview of hydraulics and pneumatics systems. It defines the terms, explains basic concepts like Pascal's law and fluid power transmission. It describes the working principles of hydraulic and pneumatic systems, including components like pumps, valves, actuators. Examples of applications in various industries like manufacturing, automobiles are given. The advantages and disadvantages of both systems are listed. Overall it serves as a introductory guide to the fundamentals and applications of hydraulics and pneumatics.

1. Hydraulics
and
Pneumatics
Er.N. Bharathkumar,DAE., B.E.(Aero).,
M.Tech (ET).,(Ph.D)
Junior Training Officer
Mechanic (Motor Vehicle)
Government ITI, Ulundurpet.

2. Objectives
1. The term fluid power
2. Working principle of pneumatic systems
and advantages and disadvantage
3. Working principle of hydraulic systems
and advantages and disadvantages.

3. Fluid Power Systems
• Fluid power is the driving force in most
industrial and mobile applications.
• A bulldozer or excavator used for moving soil
where a new project is being built, and a brake
used in a car or truck are some examples of
where fluid power is used. Fluid power
involves the use of a fluid medium, such as air
or oil, in a controlled manner, to get some
useful work.

4. • Two specialized areas cover the scope of the
definition of the term 'fluid power'. They are:
(1) Pneumatics and (2) Hydraulics.
• Transmission and control of power by means
of air is called pneumatics and transmission
and control of power by means of liquid is
called hydraulics

5. Pascal's law (Blaisé Pascal, 1623-1662)
• The law states that 'pressure exerted on a fluid
is transmitted equally in all directions, acting
with equal force on equal areas'.
• Video 1 (Pascal law)

6. Pressure is the result of the resistance offered to compression when an
incompressible oil medium is squeezed by the application of a force

7. Units of Pressure: There are many units of pressure, such as Pascal (Pa), bar,
pounds per square inch (psi), Kg/ cm2, etc., used in industrial world
1 Pascal = 1 N/m2
1 bar = 100000 Pa = 105 Pa (100 kPa)
1 bar = 14.5 psi
1 bar = 1.02 kgf/cm2

8. Hydraulic Force
• When a pressure (P) is applied onto the area
(A) of a cylinder piston, a force (F) is
developed. The amount of force developed is
equal to the area times the applied pressure.
That is,
F = P x A

9. F1 = P x A1 F2 = P x A2
F2 = F1 x (A2/ A1)

10. Flow Rate
Flow rate of oil is a measure of the volume of
the oil passing a point per unit of time. It is
usually measured in m3/ s or litre per minute
(lpm) or in other units

11. Oil Flow
A hydraulic system, with a pump pushing oil
continuously through a pipeline, produces a oil
flow between any two points in the pipeline as
long as there is a pressure differential between
these two points.

12. Hydraulic Oil
• Hydraulic oil is the lifeblood of any hydraulic
system. Its primary function is to transmit
power from one part of the system to the other
part. Apart from this function, it has to
lubricate the internal moving parts of system
components, seal clearance between the
moving parts, and act as a heat transfer
medium, as it flows through the system.

13. • Mineral-based oils (i.e., petroleum-based oils)
are used in a majority of applications. The
purpose of using additives in oil is to improve
the performance of the oil for a give
application. Oil's resistance to flow, expressed
in terms of its viscosity, is an important
parameter that must be considered.

14. Clean state
• The most important requirement of any
hydraulic system is to maintain its oil medium
in a clean state. Hydraulic filters are used to
remove solid contaminants in hydraulic oil.

15. Viscosity
• Viscosity is a measure of a liquid's resistance
to flow. Thicker oil has more resistance to flow
and possesses a higher viscosity. Viscosity is
affected by temperature. Oil viscosity
decreases as the temperature of oil increases.
• A property, that describes the difficulty with
which oil moves under the force of gravity, is
called kinematic viscosity. It is measured in
terms of stokes

16. CONCEPT OF HYDRAULIC SYSTEM
•“hydra” is Greek word means water. “aulos” means pipes.
So the name “hydraulics”.
•Man have used water as working component for his need. But the
limitations of water used as working medium were observed as
follows.
•Water causes corrosion to metals.
•It has low melting point of just 1000c which is very low.
•It has high oxidation and cavitations property.
•Due to these reasons oil is used as working fluid.
Hydraulics is a branch of applied science which
deals with energy transfer and control with oil as 2
working medium.

17. Advantages Of hydraulic System:
1. Can generate very high pressure up to 1000 bars
or even more
2. Weight to power ratio is less than mechanical,
electrical systems
3. Accuracy of system is more.
4. Hydraulic motors are bi-directionally operated.
5. No need of external lubrication
6. Noise less, vibration less operation
7. Flow can easily controlled
8. Division and distribution of power is simpler
and easier 3

18. Disadvantages of hydraulic system:
1. High initial and running cost
2. Leakage problems are more
3. Hydraulic oil can’t be stored under pressure for
large quantity
4. Can’t be used in fired regions like mining
5. Maintenance- complex, costly
6. In cold climate, oil gets freeze
7. System is gummy and dirty so not used in food
processing
4

19. Simple Application Example
Hydraulic
DCV
Filter
Tank
Introduction to Hydraulics and
Pneumatics- Aditya Deshpande

20. Non-return Hydraulic Valve

21. Flow Control (Throttle) Valve
• VIDEO 2

22. Extensive use of hydraulics is due to
the following facts
1. Oil is practically incompressible
2. Oil can transmit high forces rapidly and
accurately
3. Simple step-less control of speed, force or torque
4. Have simple over load protection
5. Simple, compact and highly reliable

23. Hydraulic systems in modern
Automobiles
1. Fuel injection system
2. Lubrication system
3. Brake system
4. Steering system
5. Shock absorbers
6. Adoptive suspension system
7. Automatic transmission system
8. Clutch actuating mechanism
9. Jack
10. Hoist
11. Bearing puller etc

24. Hydraulic steering
29

25. Hydraulic die
casting
machine
Applications of hydraulic system:
6

26. Applications of hydraulic system:
7

27. Applications of hydraulic system:
8

28. Hydraulic
forging
machine
Applications of hydraulic system:
9

29. Hydraulic excavator
10

30. Hydraulic cranes
Introduction to Hydraulics and
Pneumatics- Aditya Deshpande
11

31. Hydraulic Dry
ice fog machine
Applications of hydraulic system:
12

32. 13

33. Applications of hydraulic system:
Use of hydraulic
crane for fire
extinguishing
14

34. Applications of hydraulic system:
Hydraulic wood splitter
15

35. Hydraulic press
16

36. Hydraulic shearing machine
Applications of hydraulic system:
17

37. Hydraulic power press
Applications of hydraulic system:
19

38. Hydraulic broach
machine
Applications of hydraulic system:
20

39. Hydraulic lathe chuck
Applications of hydraulic system:
22

40. Hydraulic (CNC)
Guillotine Shearing Machine
Applications of hydraulic system:
23

41. Applications of hydraulic system:
Hydraulic cylindrical grinder
machine
24

42. Hydraulic plastic injection
moulding
Applications of hydraulic system:
25

43. Hydraulic brakes
26

44. 27

45. Hydraulc jacks

46. CONCEPT OF PNEUMATIC SYSTEM
• “pneum” is Greek word means air. So the name
“pneumatics”.
•Second branch of fluid power after hydraulic
system
•It resembles the hydraulic system in structure but
applications are limited due to compressible
nature of air
Pneumatics is a branch of applied science which
deals with energy transfer and control with air as
working medium.
30

47. Advantages Of pneumatic System:
3. Explosion proof properties make it used in
hazardous area
4. Air can easily transferred through pipes
5. No need of reservoir so system is compact, light
weight
6. Low initial and running costs
7. Maintenance is easy and simple
8. One compressor can used for many systems
9. Compressed air can be stored in tank under
pressure
1. Air is freely and easily available
2. Neat and clean system so used in food industries
31

48. Disadvantages of pneumatic system:
1. Less operating pressure up to 11n bar(main
limitation)
2. Accuracy of system is less than hydraulic
3. System is noisy
4. Separate lubricator is required
5. Necessity of air storage is required all times
even there is no load on system
6. Size of cylinder is larger
32

49. General layout of pneumatic system
compressor Air reservoir
Moisture
separator
Air filter
Lubricator
Air in
Actuator
Air out
Valve
Pressure
regul3a3tor

50. Video 3
Actuator
Simple Application Example
Pneumatic

51. Air brake
35

52. ApplicP
an
teu
im
oa
nha
smm
oe
fr
pneumatic system:
Pneumatic hammer
36

53. Applicationsofpneumaticsystem:
37

54. Pneumatic screw
driver
Applications of pneumatic system:
IntroductiontoHydraulicsand
Pneumatics-AdityaDeshpande
38

55. Pneumatic die grinder 39

56. Pneumatic spray guns
40

57. Pneumatic arm
Applicationsofpneumaticsystem:
41

59. Actuated position
Normal position
2/2-directional
control valve
3/2-directional
control valve
(Normally closed)
3/2-directional
control valve
(Normally
open)
4/2-directional
control valve
4/3-directional
control valve

60. Any
Queries??

61. Er.N. Bharathkumar DAE., B.E.(Aero).,
M.Tech (ET)., (Ph.D)
Junior Training Officer
Mechanic (Motor Vehicle)
Government ITI, Ulundurpet.
Ph. 9524008000
wifi0047@gmail.com