EENG 110
LECTURE 1:
Festo
- German multinational company
- Founded in 1925
- By Albert Fezer and Gottlieb Stoll
Pneumatics
- From Greek word “pneuma” which means
“to breath”
- Branch of fluid power
- Uses compressed air or other gasses
Electricity – medium used is electric current
Hydraulics – medium used is liquid
Mechanics – medium used is mechanical motion
APPLICATIONS OF PENUMATICS
TECHNOLOGY
 Bus Doors
 Automatic Production Lines
 Bottle Filling System
 Conveyors
 Pick and Place System
ADVANTAGES OF COMPRESSED AIR
 Availability – air is available everywhere
 Transport – air is easily transported in
pipelines
 Storage – compressor does not need to
be in continuous operation
o Compressed air can be stored in
reservoir
o Reservoir is transportable
 Temperature – compressed air is
insensitive to temperature fluctuations
 Overload Safe – pneumatic tools can be
loaded to the point of stopping
 Cleanliness – unlubricated exhaust air is
clean and does not cause contamination
 Components – components are simple to
construct
 Speed – compressed air is very fast
o High working speeds are
obtainable
DISADVANTAGES OF COMPRESSED AIR
 Preparation – dirt and condensate should
not be present
 Compressible or Non-Uniform Force –
constant piston speed is hard to achieve
 Force Requirement – small loads of
<50kN
 Noise Level – exhaust is loud but is solved
by silencers
APPLICATIONS WITH PNEUMATICS
 Chemical Industry
 Petrochemical Industry
 Food Industry
 Packaging industry
 Printing and Paper Industry
 Drinking Water and Waste Water
STRUCTURE AND SIGNAL FLOW OF
PNEUMATIC SYSTEM
ENERGY SUPPLY
Compressor
- Mechanical flowing device designed to
increase pressure of gas by reducing
volume
- Main component of basic refrigeration
- Heart of a cooling system
- Works as pump
- Energy source of pneumatic systems
- Provides operating pressure
- Most Common are reciprocating and
screw compressors
- Atmosphere: p = 0 bar
- Compressor: p = 5-7 bar
- Multi-stage reciprocating compressor
o Attain higher operating pressure
o Provide cooling of compressed air
Fluid
- Substance with no fixed shape
- Yields easily to pressure
- Gas or liquid
Air Receiver
- store compressed air before it enters
Air Service Unit Parts
- Air Filter
- Pressure Regulator
- Air Lubricator
- Pressure Gauge
Filter
- Cleans compressed air by removing
impurities:
o Dust
o Small particles
o Pipe scales
o Rust
o Water condensate
o Oil
o Without water drain
o
Actuators
- Output device convert supply energy to
useful work
- Linear Motion:
o Produce motion in straight line
o Pneumatic and hydraulic cylinders
mostly used to produce linear force
o Single acting cylinders
 One-direction, uses spring
 Forward Effective Force
 𝐹 = 𝑝 ∗ 𝑎 − 𝐹𝐹𝑅 − 𝐹𝑆
 Return Effective Force
 𝐹 = 𝐹𝑆 − 𝐹𝐹𝑅
o Double acting cylinders
- Rotary Motion
o Air Motor
o Rotary Actuators
- End Effectors
- Linear Actuators
o Produce motion in straight line
o Pneumatic and hydraulic cylinders
mostly used to produce linear force
Rotary Actuators
- Rotational motion in a limited angle
- Swivel is made by rotary and vane
cylinders
- Rotary Cylinders
o Double acting cylinder with internal
teeth
o Uses teeth and gear wheel to turn
linear to rotary
With water drain
o
Centrifugal Separator
- Filter for water droplets and large dusts
(>50 microns)
Pressure Regulator
- Used to obtain:
o Uniform speed
o Uniform force and torque
Lubricator
- Gives compressed air with fine oil mist
(lubricant)
- Should be used sparingly to avoid
clogging

Applies to all vane and
rotary cylinders
- Rotary Vane Cylinders
o Energy is directly converted to
rotary motion
o Does not use teeth and gear
o Force directly transmitted to the
shaft
- Rotary Vane Motors
Pneumatic Motors
- Transform pneumatic energy to
continuous rotary motion
LECTURE 2:
Energy supply is always drawn at the bottom of
the diagram
Control System
- Device that controls the cylinder
Directional Control Valves
- Devices which influence the path of air
- Used to control drive components
SYMBOLS:
 Valve switching position
 Number of squares = number of switching
positions
 Lines indicate flow path
 Arrows show direction of flow
 Shut-off positions are lines drawn at right
angles (T or perpendicular)
 Connections (both inlet or outlet) are lines
outside the box
DESIGNATION OF WORKING AND PILOT
LINES ON DIRECTIONAL CONTROL VALVES
Connection Function
Designation
Working
Supply
1
Lines (all
Working
2,4
valve types)
Exhaust
3,5
Pilot Lines Close Supply Port
10
1-2 Connection
12
1-4 Connection
14
Auxiliary Pilot Air
81,91
METHODS OF ACTUATION
 Manual Operated
 Pneumatic Operated
 Electrical Operated
 Combined Operated
METHODS OF ACTUATION
Manual Operated – simple levers and paddles
 Lever
 Pedal
 General
 Detent
 Push button
Mechanical
 Roller
 Ball Seat
 Idle roller
Pneumatic – switching by air signal to pilot part
 Air Pilot/Spring Return
 Air Pilot on both sides
Combined – DCV contains more than one
operation
VALVES
 2/2-way valves
 3/2-way valve ball seat
 3/2-way valve
 3/2-way valve disc seat
 3/2-way valve roller operated
 3/2-way valve single pilot
 4/3-way valve mid position
 5/2-way longitudinal slide valve
 5/2-way valve double pilot
 5/2-way valve
 5/3-way valve
LECTURE 3
Noise Attenuation on Exhaust
- Resolved by silencers and mufflers at
exhaust ports
Silencers/Mufflers
- Also reduces speed of exhaust
- Increases area over which flow takes
place
Shuttle Valves
- Logical-OR operation
Dual Pressure Valves
- Logical-AND operation
Non-Return Valve or Check Valves
- Allow fluid to pass only in one direction
- Bypass device
-
APPLICATION OF CHECK VALVES
 Bypassing flow to a device in specific
direction
 Protection of pump to back-pressure
 Vacuum system
Flow Control Valves
- Restricts flow of air to reduce flow rate
- Reduce pressure build to reduce speed
-
- Influence volumetric flow rate
- Generally adjustable and can be locked
- Never close flow control valve completely
One-Way Flow Control Valve
- Combination of flow control valve and nonreturn valve
- Free flow in one direction
- Directly on cylinder or as near as possible
WAYS OF THROTTLING USING ONE-WAY
FLOW CONTROL VALVE
Exhaust Air Throttling/Metering Out
- Supply air freely to piston side and oneway flow control valve is connected to
exhaust side to offer resistance on
discharge side
- Advantage of exhaust-air flow control is
chamber is filled quickly to build minimum
pressure to generate motion
- Continuous motion free from stick/slip
effect
Supply Air Throttling/Metering In
- No air cushioning at exhaust, and one-way
flow control valve is connected to supply
to restrict incoming flow
- Used for cylinders with small diameter or
short stroke
- Operate with small amount of air
- Effect of air cushion would be too small
- Used with single-acting cylinders if speed
is limited in stroke direction where relevant
cylinder chamber is filled with air
- Mostly used with single-acting cylinders