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Basic Pneumatics
Module 2: Air generation and
Distribution
PREPARED BY
Academic Services
August 2011
© Applied Technology High Schools, 2011
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
Module 2: Air generation and distribution
Module Objectives
After the completion of this module, the student will be able to:
Identify the main parts of a pneumatic system.
Identify the main components of the pneumatic work station TP 101.
List the main parts in the compressed air preparation stage.
Identify the symbol of air compressor and its function.
Identify the symbol of air tank and its function.
Explain the purpose of using the cooling and drying unit.
Identify the main parts of the air service unit.
Identify the symbol of air filter and its function.
Identify the symbol of air pressure regulator and its function.
Identify the symbol of lubricator and its function.
Identify some important pneumatic accessories.
Module Contents Topic Page No.
1 Introduction 3
2 Main parts in the compressed air preparation 3
3 Air compressor 4
4 Air tank 5
5 Cooling and drying unit 6
6 Shut off valve 7
7 Piping 7
8 Air service unit 9
9 Pressure regulator 10
10 Air lubricator 10
11 Manifold 11
12 Tubes and fittings 11
13 Pressure gauge 12
14 Safety precautions 13
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
1 Introduction
Air generation and distribution
The main function of the air generation and distribution is to provide the
system with compressed air which is dry, clean, and at the required
pressure.
The compressed air supply for a pneumatic system should be adequately
calculated and made available in the appropriate quality.
Air is compressed by the air compressor and delivered to an air distribution
system in the factory. To ensure that the quality of the air is acceptable,
air service unit is utilized to prepare the air before being supplied to the
control system.
Malfunctions can be considerably reduced in the system if the compressed
air is correctly prepared.
2 Main parts in the compressed air preparation
1- Air compressor
2- Air tank (Reservoir)
3- Air filter
4- Cooling and drying unit
5- Shut off valve
6- Piping
7- Air Service unit
8- Pressure regulator
9- Air lubricator
10- Manifold
11- Tubes and fittings
12- Pressure Gauge
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
(a) Air compressor
(b) Air compressor
(c) ISO symbol of air compressor
Fig. 2.1: (a) and (b) are examples of some practical air compressors. (c) ISO symbol of air compressor
2.1 Air compressor
Air compressor is used to produce
the compressed air for the system
by the required volume and
pressure.
As a rule, pneumatic components
are designed for a maximum
operating pressure of 800-1000 kPa
(8 - 10 bar) but in practice it is
recommended to operate at
between 500-600 kPa (5 and 6 bar)
for economic and safe use.
Due to the pressure losses in the
distribution system, the compressor
should provide pressure between
650-700 kPa (6.5 and 7) bar.
Fig. 2.1.a and Fig. 2.1.b are
examples of air compressors while
Fig. 2.1.c shows the ISO symbol of
the air compressor.
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.2 Air Tank (reservoir)
An air reservoir should be fitted to:
Store and stabilize
the compressed air.
Compensate the pressure
fluctuation.
Cool the air.
Fig. 2.2 (a) shows a real air tank while
Fig. 2.2 (b) shows the ISO symbol of an
air reservoir.
(a) Air reservoir
(b) ISO symbol of air reservoir
Fig. 2.2: (a) air reservoir. (b)
ISO symbol of an air reservoir.
2.3 Air Filter
Compressed air filter (Fig. 2.3a) has the
job of removing all contaminants from
the compressed air flowing through it as
well as water which has already
condensed. The compressed air enters
the filter bowl through guide slots.
Liquid particles and larger particles of
dirt are separated centrifugally
collecting in the lower part of the filter
bowl. The collected condensate must be
drained before the level exceeds the
maximum condensate mark, as it will
otherwise be re-entrained in the air
stream.
(a)A picture of a real air filter
(b) ISO symbol of the air filter
Fig. 2.3: (a) air filter.(b) The
ISO symbol of an air filter
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.4 Cooling and drying unit
As the air comes out from the
compressor very hot and humid;
The cooling and drying unit is
used to:
Condensate the water vapor
(humidity) from the
compressed air.
Reduce the compressed air
temperature. (cooling)
The accumulation of condensate
depends largely on the relative
air humidity. The relative air
humidity is dependent on the air
temperature and the weather
situation.
To remove the humidity, we use
many types of air dryers, the
very common and practical one
is by using a cooling unit which
cool the air and at the same
time remove the water vapor.
Fig. 2.4 (a) and (b) show some
examples of real air dryers,
while Fig. 2.4.c represents an
ISO symbol of air dryer.
(a)
(b)
(c)
Fig. 2.4: (a): and (b) are some
examples of real air dryers.
(c) ISO symbol of air dryer.
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.5 Shut off valve
It is used to open and close the
compressed air supply
manually.Fig. 2.5.a shows a sample
of shut-off valve. Fig. 2.5.b
represents the ISO symbol of the
shut-off valve.
(a) Sample of a shut-off valve
(b) ISO symbol of the shut-off valve
Fig. 2.5: (a) picture of shut off
valve.
(b) The ISO symbol of shut off
valve
2.6 Piping
The pipe diameter of the air distribution system should be selected in
such a way that the pressure loss from the pressurized reservoir to the
consuming device ideally does not exceed approx. 10 kPa (0.1 bar).
2.6.1 Selection factors of the pipe diameter:
1. Flow rate
2. Line length
3. Permissible pressure loss
4. Operating pressure
5. Number of flow control points in the line
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.6.2 Piping layout
Ring circuits (Fig. 2.6.a) are most
frequently used as main lines. This
method of installing pressure lines
also achieves a constant supply in
the case of high air consumption.
In pipe-run layout, the pipe lines
must be installed in the direction
of flow with a gradient of 1 to 2%
as shown in Fig. 2.6.b. This is
particularly important in the case
of branch lines.
Condensate can be removed from
the lines at the lowest point.
Any branching of air consumption
points where lines run horizontally
should always be installed on the
upper side of the main line.
Shut-off valves can be used to
block sections of compressed air
lines if these are not required or
need to be closed down for repair
or maintenance purposes.
(a) Ring (loop) pneumatic
distribution system
(b) pipe-run pneumatic distribution
system
Fig. 2.6 : (a) shows the ring or loop
distribution system. (b) shows the
pipe-run distribution system
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.7 Air service unit
The air service unit shown in Fig.
2.7.a is a combination of the
following:
1. Compressed air filter (with
water separator)
2. Compressed air regulator
3. Compressed air lubricator
Fig. 2.7.b is the air service unit
without lubricator in our labs.
The main function of the service unit
is to provide the pneumatic system
with a well cleaned, lubricated and
regulated compressed air.
(Condition the compressed air).
Fig. 2.7.a and Fig. 2.7.b Show some
real air service unit. And Fig. 2.7.c
shows the detailed ISO symbol of
the service unit. While Fig 2.7.d
shows the Simplified ISO symbol of
the service unit.
(a) A picture of an air
service unit
(b) A picture of an air
service unit
(c) Detailed ISO symbol of the
service unit
(d) Simplified ISO symbol of the
service unit
Fig. 2.7
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.8 Pressure regulator
(Reduce/regulate the pressure).
The purpose of the regulator (Fig. 2.8.a)
is to keep the operating pressure of the
system (secondary pressure) virtually
constant regardless of fluctuations in
the line pressure (primary pressure) and
the air consumption. Fig. 2.8.b
represents the ISO symbol of the air
regulator.
(a) Pressure regulator
(b) ISO symbol of the pressure
regulator.
Fig. 2.8: (a) pressure
regulator.(b) ISO symbol of the
pressure regulator.
2.9 Air lubricator
(Lubricate the moving parts)
Most moving parts require some type of
lubrication. The efficiency of cylinders, valves
and air motors can be greatly improved if they
are supplied with adequate lubrication.
Pneumatic components can be lubricated by
using an air line lubricator (Fig. 2.9.a), a
device for adding lubricating oil in aerosol
form into a compressed air line. The air
passing through the lubricator transports the
lubricant to air tools, cylinders or other air
operated equipment. Fig. 2.9.b represents the
ISO symbol of the air lubricator.
(a) air lubricator
(b) ISO symbol of the air
lubricator.
Fig. 2.9
(a) Air lubricator. (b)ISO
symbol of the air
lubricator.
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.10 Manifold (distributor)
It is used to provide multi equal
pressure outlets. Fig. 2.10.a shows
a pneumatic manifold (distributor).
Fig. 2.10.b represents the ISO
symbol of the pneumatic pressure
source.
Fig. 2.10.c represents the ISO
symbol of T junction.
Each output port has check valve
(Non return valve).
(a) pneumatic manifold (distributor)
(b) ISO symbol of the pressure
source
(c) ISO symbol of T junction
Fig. 2.10
2.11 Tubes and fittings
Fig. 2.11.a shows some types of tubes
that are used in connecting pneumatic
circuits.
Fig. 2.11.b shows some important
fittings such as T connections and
cross connections.
(a) some types of tubes
(b) some types of fittings
Fig. 2.11
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
2.12 Pressure gauge
It used to display the actual amount
of the pressure in two main units PSI
and bar.
1 bar= 14.7 PSI
Fig. 2.12.a shows a real pressure
gauge. Fig. 2.12.b represents the ISO
symbol of the pressure gauge.
(a) pneumatic pressure gauge
(b) ISO symbol of a pressure
gauge
Fig. 2.12
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
5. For further reading, you can use the following links:
1- www.Fest-didactic.com 2- http://www.eng2all.com/vb/t28932.html 3- http://www.logiclab.hu/lesson.php?fe=2
6. Supplementary recourses
1- Pneumatics video from Festo.
2- FluidSIM software.
7. References
1- Festo manuals and workbook TP101 2- Festo manuals and textbook TP101
ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
Student’s notes
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ATM 1132 – Basic Pneumatics
Module 2: Air generation and distribution
Worksheet 1 QI) Draw the ISO Symbols for the following components:
1- Air compressor …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
2- Air filter
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
3- Shut off valve
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
4- Pressure gauge
………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… Q2) what is the function of the following components:
1- Air tank …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
2- Manifold
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
3- Pressure regulator
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
4- Air service unit
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………