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EXPERIMENT : PNEUMATICS
APPARATUS : TP101 Festo Basic Level Pneumatics Toolbox
Festo Fluidsim software
THEORY :
Pneumatics
Pneumatic controls are very common in industrial use, primarily for applications that require a fixed distance travel of or reciprocation of objects. Ex:- transfer of materials between conveyors, clamping objects for assembly or testing, punch presses etc. Compressed air is used to generate the actuating action
Major functions of pneumatics
Determine the status of processors(sensors) Information processing(processors) Switching of actuators by means of final control elements Carrying out work(actuators)
In industry,electricity,fluid(hydraulics) and compressed air(pneumatics) use as a working media.
Pneumatic control system architecture
Page 1
Symbols of used components in this experiment
Methods of actuation of pneumatics valves are
Manual Mechanical Pneumatic Electrical Combined
Manual Mechanical
Page 2
Pneumatic Electrical
Page 3
Practical No.01 – Direct Control of a Single Acting Cylinder
Task:-
A single acting cylinder is to clamp a component when a push button is pressed. As long as the push button is activated, the cylinder is to remain in the clamp position. If the push button is released, the clamp is to retract.
Apparatus used:
3/2-way valve with selector switch, normally closed3/2-way valve with pushbutton actuator, normally closedSingle-acting cylinderStart-up valve with filter control valvePressure regulator valve with gaugeManifoldPlastic tubing (10 m,PUN 4x0.75)
Procedure:
First a sketch was drawn and then circuit was design using festo fluidsim software. Then circuit was simulated and checked according to given task. Necessary corrections were made according to given task when simulating to perform the given task correctly. Finally simulated circuit was buildup on the festo pneumatic workbench using relevant components. After circuit was build , compressed air was supplied to circuit and check where its working according to given task.
Page 4
Pneumatics Circuit Diagram And Simulation For Practical No.01
Page 5
Practical No.02 – Direct Control of a Double Acting Cylinder
Task:-
A double acting cylinder is to extend when a push button is operated. Upon release of the pushbutton the cylinder is to retract.
Apparatus used:
3/2-way valve with selector switch, normally closed5/2-way valve with selector switch (with pushbutton actuator valve required,
use this due to unavailability)Double-acting cylinder Start-up valve with filter control valvePressure regulator valve with gaugeManifoldPlastic tubing (10 m,PUN 4x0.75)
Procedure:
First a sketch was drawn and then circuit was design using festo fluidsim software. Then circuit was simulated and checked according to given task. Necessary corrections were made according to given task when simulating to perform the given task correctly. Finally simulated circuit was buildup on the festo pneumatic workbench using relevant components. After circuit was build , compressed air was supplied to circuit and check where its working according to given task.
Page 6
Pneumatics Circuit Diagram And Simulation For Practical No.02
Page 7
Practical No.03 – Indirect Control of a Single Acting Cylinder
Task:-
A single-acting cylinder with a large piston diameter is to clamp a workpiece following actuation of a push button. The cylinder is to retract once the push button is released.
Apparatus used:
3/2-way valve with selector switch, normally closed3/2-way valve with pushbutton actuator, normally closed3/2-way pneumatic valve, pneumatically actuated, one sideSingle-acting cylinder Start-up valve with filter control valvePressure regulator valve with gaugeManifoldPlastic tubing (10 m,PUN 4x0.75)
Procedure:
First a sketch was drawn and then circuit was design using festo fluidsim software. Then circuit was simulated and checked according to given task. Necessary corrections were made according to given task when simulating to perform the given task correctly. Finally simulated circuit was buildup on the festo pneumatic workbench using relevant components. After circuit was build , compressed air was supplied to circuit and check where its working according to given task.
Page 8
Pneumatics Circuit Diagram And Simulation For Practical No.03
Indirect control is useful when controlling high load with using pneumatics.When use indirect control high pressure handing output valve required and other valves/components in the controlling circuit are working with normal low pressure.If try to use direct control all valves,component require with that output high pressure. Therefore when handling high load, indirect control is required.
Page 9
Practical No.04 – Indirect Control of a Double Acting Cylinder with Speed Control of a Cylinder
Apparatus used:
3/2-way valve with selector switch, normally closed3/2-way valve with pushbutton actuator, normally closed5/2-way valve with selector switch (with pushbutton actuator valve required,
use this due to unavailability)5/2-way double pilot valve, pneumatically actuated, both sides Double-acting cylinderOne-way flow control valves - 2Start-up valve with filter control valvePressure regulator valve with gaugeManifoldPlastic tubing (10 m,PUN 4x0.75)
Procedure:
First a sketch was drawn and then circuit was design using festo fluidsim software. Then circuit was simulated and checked according to given task. Necessary corrections were made according to given task when simulating to perform the given task correctly. Finally simulated circuit was buildup on the festo pneumatic workbench using relevant components. After circuit was build , compressed air was supplied to circuit and check where its working according to given task.
Page 10
Pneumatics Circuit Diagram And Simulation For Practical No.04
Page 11
Practical No.05 – Roller Lever Operation af a Double Acting Cylinder With Speed Control of a Cylinder
Apparatus used:
3/2-way valve with selector switch, normally closed5/2-way valve with selector switch (with pushbutton actuator valve required,
use this due to unavailability)5/2-way double pilot valve, pneumatically actuated, both sides 3/2-way roller lever valve, normally closedDouble-acting cylinderOne-way flow control valves - 2Start-up valve with filter control valvePressure regulator valve with gaugeManifoldPlastic tubing (10 m,PUN 4x0.75)
Procedure:
First a sketch was drawn and then circuit was design using festo fluidsim software. Then circuit was simulated and checked according to given task. Necessary corrections were made according to given task when simulating to perform the given task correctly. Finally simulated circuit was buildup on the festo pneumatic workbench using relevant components. After circuit was build , compressed air was supplied to circuit and check where its working according to given task.
Page 12
Pneumatics Circuit Diagram And Simulation For Practical No.05
Page 13
DISCUSSION
In this experiment direct and indirect control of actuation done by using pneumatics.
Indirect control is useful when controlling high load with using pneumatics.When use indirect control high pressure handing output valve required and other valves/components in the controlling circuit are working with normal low pressure.If try to use direct control all valves,component require with that output high pressure. Therefore when handling high load, indirect control is required.
In the practical of indirect control of a double acting cylinder with speed control of a cylinder, we learned how to control the air flow using flow control valves.
In the practical no.05 – roller lever operation af a double acting cylinder with speed control of a cylinder, we learned how use signal input devices in pneumatics circuit . We used 3/2-way roller lever valve, normally closed for get input of the position of cylinder.
We learned how to work supply elements, input elements, processing elements, control elements and power components using festo pneumatics work bench and components. Fluidsim software used to design and simulation of the given circuits. After simulation, all circuits prepare and run on the festo workbench.
Applications of Pneumatics
Application Characteristics
Platform positioning
Good dynamics
Large working efforts
Accuracy of positioning
Simplicity of a design
Tightening devices
The big efforts of a clip
Compactness
Small weight
Page 14
Sorting levers Big working efforts and acceleration
Simplicity of a design
Amortization of working loadings
Elevating devices Big working efforts and acceleration
Amortization of working loadings
Simplicity of a design
The
scheme of the mobile robot:
Page 15
Brake actuator Good controllability
Absence of friction of rest
Simplicity of a design and operation
Underwater devices
Corrosion preventing
Tightness
Small consumption of working gas
Walking platforms
Good dynamics
Simplicity of a design
Small weight
Ease of positioning
Counterbalancing devices
Adjustment of elasticity
Adaptibility of characteristics
Smoothness of job
Small weight
1,2 – longitudinal pneumatic cylinders; 3,4 – transversal pneumatic cylinders; 5 – lifting cylinder; 6 – pedipulator; 7 – metaldetector; 8 – infra-red sensor; 9 – the chemical sensor; 10 – sensor of longitudinal position movement; 11 - sensor of cross-section position movement; 12 - block of valves; 13 – block of rotation; 14 – electronic compass; 15 – onboard compass
The scheme of batching:
1 – tank; 2 – fluid; 3 – a lever with a ladle; 4 - power cylinder; 5 – accepting chamber
Page 16
The scheme of the pneumatic processing center for material’s sawing:
1 -work material; 2 -a power cylinder for a longitudinal motion; 3 - a power cylinder for a vertical motion; 4 – saw; 5 – supports; 6 – rotary actuator
Packaging industry Automobile industry
Advantages and disadvantages of pneumatics
Page 17
Advantages:
• simplicity of realization relatively to small back and forth motions;
• sophisticated transfer mechanisms are not required
• low cost
• high speed of moving
• ease at reversion movements
• tolerance to overloads, up to a full stop.
• high reliability of work
• explosion and fire safety
• ecological purity
• ability to accumulation and transportation
• normally air is available in unlimited quantities in any place
• after compressed, air can be stored in reservoir.
• relatively insensitive to temperature fluctuations.
• unlubricated exhaust air is clean
• very fast working medium. High working speed
Disadvantages:
• compressibility of the air
• impossibility to receive uniform and constant speed of the working bodies movement
• difficulties in performance at slow speed
• limited conditions – use of compressed air is beneficial up to the definite values of pressure (the cost of compressed air productior increases sharply when the pressure in the system exceeds 8…10 bar)
• compressed air requires good preparation (the air should be cleared of mechanical impurity and should be free of moisture)
• Exhaust air is loud.Can prevent some levels by sound absorption materials and silencers.
Page 18