Module 5: Direct and Indirect control of
double acting cylinder
Module Objectives
Upon the completion of this module the student will be able to:
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Control of the double acting cylinder directly using 5/2 way valve, selector
switch
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Control of double acting cylinder indirectly with 5/2 way valve, single pilot
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Draw symbol of double acting cylinder and 5/2 way valve.
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Identify the function and the use of 5/2 way valve and double acting
cylinder
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Construct a complete circuit diagram of controlling double acting cylinder
directly and indirectly.

Check the circuit operation and troubleshot any malfunctions.

Simulate the circuit diagram using FluidSIM software.
1- Double acting cylinder
Definition:
It is an output device and is
considered to be as a main
actuator in any pneumatic
systems.
Function:
used for the conversion of supply
energy (pneumatic) into useful
work (linear motion).
Way of Operation
(Double acting cylinder is able to
carry out work in both directions of
motion).
Characteristics:
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Double acting cylinders are more expensive than single acting
cylinders,
Double acting cylinders are superior to single acting cylinders by any
other important measure.
Double acting cylinders are faster and stronger.
In industrial applications, single acting cylinders are used if possible,
but when speed and force are important double acting cylinders are
employed.
Applications include
A.
B.
C.
D.
E.
Opening and closing doors.
Taking things off conveyor belts.
Putting things on conveyor belts.
Lifting and moving packages around .
Used for presses and punches.
Serial
Single acting cylinder
Double acting cylinder
1
It has one port
It has two ports
2
It has a spring
It has no spring
It exerts work in one
It exerts work in two directions
direction only
(forward and backward)
3
It uses compressed air in
4
the forward stroke while
It uses compressed air in both
the return stroke is
strokes forward and backward.
achieved by the spring
1 Forward (advanced) stroke
The air is supplied to port (1) and the
exhaust air is forced out through port (2) as
illustrated in Figure (3.1.c)
2 Backward (return) stroke:
(c) Double acting cylinder advanced
stroke
The air is supplied to port (2) and the
exhaust air is forced out through port (1) as
illustrated in Figure (3.1.d)
(d) Double acting cylinder return stroke
Note: The force produced by the piston
during the advance stroke is greater than
the force produced during the return
stroke due to the area difference between
Figure 3.1
the two sides of the piston.
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Cylinders with large piston diameters have high air
consumption rates.
Control elements with high nominal flow rates
must be used to actuate them.
In this case, the indirect control is recommended.
Thus, the signal which is generated by the smaller
valve will provide the force required in order to
switch the main control element.
To achieve the indirect control, a single and/or
double pilot valves will be required
5.1 Learning objectives:
Upon the completion of this task, the students
will be
 able to explain and setup indirect control.
 familiar with the mode of operation of a 5/2
way-valve with pneumatic actuation.
 familiar with the difference between signaling
element and a control element.
5.2 Task description:
 A filling system fills bottles with milk. The bottles are fed to the
system on a conveyor belt and are stopped underneath the filler
using pneumatic cylinders. The double acting cylinder 1A1 (due to
its large size) has to be controlled indirectly.
 Figure (3.6) shows the positional sketch of this machine
5.3 Task requirements:
 Draw pneumatic circuit that controls the
double acting cylinder (1A1) indirectly. You
may use the provided space below.
 Simulate the circuit using FluidSim software.
 Assemble the circuit practically and check its
operation.
 Write down your observation below
Draw the pneumatic circuit here
Describe double acting cylinder and draw its ISO symbol
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What is the function of the 5/2 way valve with selector switch?
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Describe the 5/2 way valve single pilot operated & draw its ISO symbol
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What is the function of the 5/2 way valve single pilot operated?
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Draw pneumatic circuit with following conditions:
1-Double acting cylinder will extend when 3/2 way valve is actuated
(Keep pressing)
2-The double acting cylinder will retract when push button is released.