Mechatronics Lab Manual

LIST OF CONTENTS

Sl.No. TITLE Page No.

1. Fluid Power Standards 2

2. Fluid Power Symbols 3

3. Study of Hydraulic System Components 5

4. Study of Pneumatic System Components 8

5. Design of Simple Pneumatic Circuit 11

6. Design of Meter In Circuit 13

7. Design of Meter Out Circuit 15

8. Design of Continuous Cycle Circuit 17

9. Design of Sequential Circuit (Pneumatic) 19

10. Design of Synchronizing Circuit 21

11. Design of Simple Electro Pneumatic Circuit 23

12. Design of Electro Pneumatic Circuit 25

13. Design of Continuous Cycle Electropneumatic Circuit 27

14. Design of Plc Controlled Electropneumatic Circuit 29

15. Design of Simple Hydraulic Circuit 31

16. Design of Hydraulic Circuit Using Hydraulic Motor 33

17. Design of Sequential Hydraulic Circuit Using Sequential Valve 35

18. Design of Three Cylinder Sequential Circuit 37

19. Design of Sequential Circuit Using Cascade Method 40

20. Design of And / Or Logic Functions 42

21. Design And Simulation of Various Fluid Power Circuits Using

Automation Studio Software / Fluid Sim – P Software 44

22. Study And Analysis of Hydraulic System Model Using Matlab

Software 46

23. Measurement of Pressure Using Labview 8.2 49

24. Measurement of Temperature Using Lab View & 8.2 52

25. Measurement of Air Flow Using Lab View 8.2 53

Bharath University A.Kumaraswamy

FLUID POWER STANDARDS

There are various organisations devoted to standardise in the field of fluid power. The standards organisations in this field are

BS (British Standards).ISO (International Standards Organization)CETOP (Comite Des Transmissions Oleohydrauliques et Pneumatiques or European Hydraulic and Pneumatics Committee).

DRAWING CIRCUIT DIAGRAMS

The main standards for circuit drawings are as follows.Symbols must be created to standards BS2917/ISO 1219-1. You should use these throughout your studies.The layout of the drawing should conform to ISO 1219 – 2The standards for connections to the hardware are covered by ISO 9461Each component on the circuit diagram should be numbered and annotated with essential data such as pressure settings and capacity.

NUMBERING SYSTEM

The identification of ports in hydraulic and pneumatic valves are generally as follows .P – Pump 1- Power Inlet 12- PilotA – Actuator 2- To Actuator 14- PilotM - Prime Mover 3- ExhaustS – Solenoid 4- To ActuatorV – Valve 5- ExhaustZ or any other appropriate letter is used for any other component.

REPRESENTATION OF PIPES

Pipes are identified on drawings with the following letters.P - Pressure linesT - Tank or return linesL - Leakage or drainage lines

REPRESENTATION OF CYLINDERS

A, B, C are used to represent cylinders

REPRESENTATION OF LIMIT SWITCHES

a0, a1, b0, b1 and so on are used to represent roller operated direction control valve working as limit switch for the cylinders.

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FLUID POWER SYMBOLS

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EX. NO. 1STUDY OF HYDRAULIC SYSTEM COMPONENTS

AIM: To study the components of a typical hydraulic system and understand various

hydraulic components.

COMPONENTS: 1. Tank2. Pump3. Electric motor4. Control valves5. Actuators6. Piping and Hoses

DESCRIPTION

1. TANK

The tank or reservoir is used to store the hydraulic fluid. The components like oil filter, oil level indicator, filler breather, return line filter and strainer are also mounted in the tank. The size of reservoir to be selected by the rule of thumb: approximately three times of actual flow rate required for the system in liters per minute. Large tanks are provided with baffle plates to have slow movement of oil from return line to the suction.

2. PUMP

The pump, the heart of any hydraulic system, converts mechanical energy into hydraulic energy. The mechanical energy is delivered to the pump via a prime mover such as electric motor. Due to mechanical action, the pump creates a partial vacuum at its inlet. This permits atmospheric pressure to force the fluid through the inlet line and into the pump. The pump then pushes the fluid into the hydraulic system. Types of pumps used in hydraulic system are gear pump, vane pump and piston pump.

3. ELECTRIC MOTOR

An electric motor is used as a prime mover to the hydraulic system. Pump is coupled to the electric motor using any of the coupling techniques. Commonly used are bell housing, Oldham’s coupling etc.

4. CONTROL VALVES

Mainly used control valve is the pressure relief valve, fitted immediately after the pump. This prevents the pump from any damage due to overloading. Apart from relief valve, other types of pressure control valves also may be used. Direction control valves and flow control valves also present in all hydraulic circuits to change the direction of the motion of actuators and the speed of actuators respectively.

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5. ACTUATORS

Hydraulic actuators convert the hydraulic energy into mechanical energy. Based on the motion produced, the actuators are classified into following types: 1. Linear actuators (Hydraulic cylinders) which produce straight line motion 2. Rotary actuators (Hydraulic motors) which produce rotary motion and 3. Oscillators which produce partial rotary motion.

6. PIPING & HOSES

Piping which carries the liquid from one location to another. If the pipe line of the hydraulic system having more bends which leads to more frictional losses in the hydraulic system.

HYDRAULIC POWER PACK

The hydraulic tank fitted with pump, motor, relief valve and accessories is generally called as power pack. The accessories generally incorporated in a power pack are:

Oil level indicator Couplings Pressure gauge and gauge isolator Manifold block Filler breather Return line filter Suction line with required filter strainer

Drawing Practice:

Draw free hand sketch of one or two hydraulic components after seeing its cut section model.

RESULT:The components of hydraulic system are studied and understood.

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Fig. 1 Hydraulic system components

Drawing Practice:

Draw free hand sketch of one or two hydraulic components after seeing its cut section model.

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EX. NO. 2STUDY OF PNEUMATIC SYSTEM COMPONENTS

AIM: To study the various pneumatic components used in pneumatic systems and to

understand the working of them.

COMPONENTS:

1. Air Tank2. Air compressor3. Electric motor4. Air conditioners and Control valves5. Actuator6. Air hoses

DESCRIPTION:

1. AIR TANK

An air tank is used to store a given volume of compressed air. An air tank consists of air filter, air pressure indicator, water drainage tap. In small compressor units generally compressor is fit on the air tank.

2. AIR COMPRESSOR

An air compressor is a machine that compresses air from a low inlet pressure (usually atmospheric) to a higher desired pressure level. This is accomplished by reducing the volume of the gas. Air compressors are generally positive displacement units and are either of the reciprocating piston type or the rotary screw or rotary vane types.

3. ELECTRIC MOTOR

An electric motor is used to drive the compressor. Then the compressor compresses air from a low inlet pressure to a higher desired pressure level. This compressed air pressure used to do the useful work.

4. AIR CONDITIONING UNIT AND CONTROL VALVES

The conditioning of air is done by the FRL unit. The filter removes the unwanted contaminants from the compressed air and the regulator is used to regulate the pressure to the required level from the higher level. The lubricator adds the lubricating oil to the air so that the air gains some lubricating properties to minimize friction during movement of components. Control components such as directional control valves, flow control valves are also used in the pneumatic circuits.

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5. ACTUATORS

Compressor performs the function of adding pressure energy to the atmospheric air in the pneumatic system. Pneumatic actuators and motors do just the opposite. They extract energy from compressed air and convert into mechanical energy to perform useful work. There are three types of actuators: 1. Linear actuators (Pneumatic cylinders) 2.Rotary actuators (Air motors) and 3. Oscillators (Partial rotary movement).

6. AIR HOSES

Air hoses are used to carry the pressurised air from one location to other location. Steel, copper pipes and PU tubing are normally used air hoses.

Drawing practice:

Draw free hand sketch of one or two Pneumatic components after seeing its cut section model.

RESULT:The components of Pneumatic system are studied and understood.

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Fig. 2 Pneumatic system components

Drawing practice:

Draw free hand sketch of one or two Pneumatic components after seeing its cut section model.

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EX. NO. 3 DESIGN OF SIMPLE PNEUMATIC CIRCUIT

PROBLEM

A double acting cylinder is used for clamping and de-clamping work part in a drilling machine. To actuate the cylinder for clamping and de-clamping, a manually operated valve to be operated. Design a circuit.

AIM

To design a simple pneumatic circuit which can clamp and de-clamp the work part in drilling machine when actuated manually.

COMPONENTS REQUIRED

1. Double acting cylinder 12. Air supply & FRL unit 13. Manually operated 5/2 valve 14. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

Compressed air supply is given through the FRL unit to the manually operated directional control valve. The output ports of the DC valve are connected to the cylinder ports. In normal condition the cylinder is in the retracted condition (de-clamping).

WORKING OF THE CIRCUIT

When the manually operated valve is pressed, the left side configuration of the valve is come into operation and the pressurized air enters into the cover end of the cylinder causing the cylinder to move forward. This clamps the work part and after completing the drilling operation, the operator actuates the valve to the other side. This now gives air to the piston end of the cylinder retracts for de-clamping the work part.

RESULT

A circuit for the given problem is designed, constructed using the available components and tested successfully.

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Fig. 3 Simple Pneumatic Circuit

EX. NO. 4

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DESIGN OF METER IN CIRCUIT

PROBLEM

Design a simple acting cylinder circuit used to feed a drill bit. The cylinder has to move forward when a manually operated valve is actuated. The drill feed rate need to be varied as per the requirement.

AIM

To design a circuit this can give a controlled speed movement when the cylinder moves forward.

COMPONENTS REQUIRED

1. Single acting cylinder 12. FRL unit 13. 3/2 direction control valve 14. Meter in valve 15. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

Compressed air supply is given through the FRL unit to the manually operated directional control valve. One output port of the DC valve is connected to the cylinder port and the other output port is blocked. The power goes to the cylinder through the meter in valve which controls the quality of air entering into the cylinder.


When the manually operated valve is actuated, the left side of the valve configuration comes into operation and the air enters into the cylinder through the meter in valve. The flow through that valve can be adjusted to get the required speed of the cylinder which in turn controls the feed rate of the drill bit. After drilling is over the manually operated valve is actuated and the air in the cylinder is connected to the exhaust and the cylinder returns back by the string force.

RESULT


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Fig. 4 Meter in circuit

EX. NO. 5DESIGN OF METER OUT CIRCUIT

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PROBLEM

A double acting cylinder is used as a feed cylinder for boring machine. The speed control of forward and return stroke should be possible to get a positive feed control. The cylinder is actuated by a manually operated valve.

AIM

To design a double acting cylinder circuit with positive speed control.

COMPONENTS REQUIRED

1. Double acting cylinder 12. FRL unit 13.5/2 direction control valve 14. Meter out valve 25. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

To get the positive speed control, it is better to control the outgoing air to create a positive back pressure inside the cylinder always. The air from the directional control valve is given to the cylinder through meter out valves for this purpose. The direction control valve is getting air from the FRL unit.


When the manually operated valve is actuated to its left condition, the air coming out of the valve enters to the cover side of the cylinder and the piston starts moving forward. At the same time the air present in the rod side of the cylinder goes out through the controlled passage of the meter out valve. This controlled exhaust creates a positive pressure in the rod side of the cylinder and the cylinder moves slowly forward. The exhaust passage can be adjusted and the speed can thus be varied positively. For return stroke also it works in the same principle.

RESULT

The given circuit is designed, constructed with the available components and checked for working.

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Fig.5 Meter out Circuit

EX. NO. 6DESIGN OF CONTINUOUS CYCLE CIRCUIT

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PROBLEM

A double acting cylinder is used to feed material for a punching press. For every cycle one blank to be fed to the press. The cylinder has to start and stop its continuous operation when a push button valve is operated. Design a circuit.

AIMTo design a continuously operating circuit as per the given requirement.

COMPONENTS REQUIRED

1. Double acting cylinder 12. Pilot operated 4/2 valve 13. Air supply & FRL unit 14. Manually operated 3/2 valve 15. Lever operated 3/2 valve 46. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

The double acting cylinder gets power supply for its forward and return motion from the pilot operated 4/2 directional control valve. The lever operated valves are used as limit switches for the sensing of the end of the either stroke. These valves are named as a0 and a1.The output from the limit switches are connected as the pilots for operating the DC valve. The input power for the DC valve and limit switches are given from the FRL unit through the manually operated 3/2 valve. The actuation of limit switches cause the cylinder motion as follows

a0 Cylinder forward motion a1 Cylinder return motion


Initially let us assume the cylinder is in the return condition (a0 actuated) and the manually operated valve in closed condition. If the manually operated valve is actuated to open condition, air is allowed to pass to DC valve and limit switches. This leads to the air output in a0 and this causes the cylinder forward position. As the cylinder starts its forward movement, a0 is released and at the end of the stroke a1 pressed. This leads to the reversal of the DC valve and the cylinder starts its return motion. At the end of return stroke a0 got pressed and this actuates the DC valve and the cylinder moves forward. This cycle continues until the manually operated valve is moved to closed position.

RESULT


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Fig. 6 Continuous Cycle Circuit

EX. NO. 7DESIGN OF SEQUENTIAL CIRCUIT (PNEUMATICS)

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PROBLEMTwo Pneumatic cylinders are used for loading and unloading of components. The operating sequence of the cylinders is A+ B- A- B+. Design a circuit.AIMTo design a pneumatic circuit for the given sequence.

COMPONENTS REQUIRED1. Double acting cylinder 22. Pilot operated 4/2 valve 23. Air supply & FRL unit 14. Manually operated 3/2 valve 15. Lever operated 3/2 valve 46. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTIONTwo cylinders are named as A & B. The corresponding limit switches are a0 & a1, and b0 & b1 for home and extended positions respectively. The directional control valves for each cylinder are named as X & Y respectively and the cylinders are connected to them. The DC valves and individual limit switches are given with power from the FRL unit through a manually operated valve. The output from the limit switches are given as pilot to the DC valves, to make the respective cylinder to move. Manually operated 3/2 valve works as a start switch. The output from each limit switch will create movement of cylinders as follows

a1 B-- b0 A-a0 B+b1 A+

WORKING OF THE CIRCUITCompressed air through FRL unit enters to the direction control valves and limit switches. At the home condition the cylinder A is at the retracted condition and the cylinder B is in the extended condition. So limit switches a0 & b1 are in actuated condition and power comes to corresponding DC valves. The manually operated valve is in closed condition initially. If the manually operated valve is actuated to open Condition, air is supplied to direction control valves and limit switches. Since the limit switch b1 is in pressed condition the air goes to actuate the direction control valve X and the cylinder moves forward. This causes the release of a0 and pressing of a1 at the end of the stroke. The output from a1 goes to Y as pilot and shift it position. This gives power to the return stroke of cylinder B. At the end of return stroke, b0 is pressed and the DC value X reversed. This makes the cylinder A to return and at the end a0 is pressed. Due to this pilot Y is reversed and B moves forward and at the end b1 is pressed. Thus the cylinders A & B operate continuously until the manually operated valve is put in close condition.

RESULTThe given circuit is designed, constructed with the available components and checked for working.

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Fig.7 Sequential Circuit with pneumatic control

EX. NO. 8

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DESIGN OF SYNCHRONISING CIRCUIT

PROBLEM

Two pneumatic cylinders are to finish a forming operation. The forming press presses the sheet metal and at the end of the pressing operation, the cylinders must forward simultaneously to finish the operation. The movements of the cylinder must be synchronized to get good finishing of the forming. As soon as the finishing is over the cylinders need to retract immediately. Design a circuit.

AIM

To design a circuit to operate two pneumatic cylinders simultaneously with synchronized movement.

COMPONENTS REQUIRED

1. Double acting cylinder 22. Pilot operated 4/2 valve 13. Air supply & FRL unit 14. Lever operated 3/2 valve 15. Lever operated 3/2 valve with idle return 16. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

Two double acting cylinders are kept as shown in the diagram. Both the cylinders are getting air supply from one single directional control valve as shown. The idle return 3/2 (L1) valve is used to sense the end of the stroke of punching press and 3/2 lever valve (L2) is used for sensing the forward position of the cylinders. These two valves are giving pilot supply for the direction control valve. Air supply to the direction control valve and the limit switches is given through the FRL unit.


The air comes to the limit switches and DC value as soon it is on. When the limit switch L1 is pressed, the pilot supply is given to the DC valve and the air supply goes to the cylinders to the cover end and they move forward. As both the cylinders get power from same port they move simultaneously with same speed. When they complete the forward stroke, L2 is pressed and at the same time, the ram of machine starts it return motion and L1 got released. This gives power to the opposite side of the DC valve and the cylinders retract immediately.

RESULT


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Fig. 8 Synchronising Circuit

EX. NO. 9

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DESIGN OF SIMPLE ELECTRO PNEUMATIC CIRCUIT

Electro pneumatic circuit is the circuit where the electrical power is used to control the operation of the circuit components. Most of the industrial circuits are Electro pneumatic circuits for automatic control.

PROBLEM

Design an electro pneumatic circuit to activate two single acting cylinders, using a push button. When the push button is pressed cylinder A has to move forward and cylinder B has to move backward, and the vice versa when the push button is released.

AIM

To design the above said circuit and to understand the working principle of an electro pneumatic circuit.

COMPONENTS REQUIRED

1. Single acting cylinders 22. 4/2 single solenoid, spring return DC valve 13. FRL unit 14. Fittings and Hoses Required quantity5. Required electrical components

CIRCUIT DESCRIPTION

Compressed air from the FRL is given to the DC valve. One output port of the DC valve is connected to the cylinder A such that when valve is actuated, air will come to this port. The other port is connected to cylinder B. At spring returned normal condition, compressed air will go to cylinder B.

WORKING OF THE CYLINDER

At normal condition, the air will go to the cylinder B and that will be in extended condition and A will be in retracted condition. The circuit is operated by 24 V electrical supply, and the circuit is shown in the figure. When the push button is pressed, the circuit closes and the solenoid is energized. This makes the valve to actuate and the left side configuration of the valve comes to working. Now the cylinder A moves forward and B returns back due to spring force. If the push button is released, the circuit breaks and the solenoid get deenergised. This leads to the return of DC valve to its normal position and cylinder A returns and B moves forward.

RESULT

The given circuit is designed, constructed and executed successfully and the principle of working of electrical control in pneumatics is understood.

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Fig. 9 Simple Electro Pneumatic Circuit

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EX. NO. 10DESIGN OF ELECTRO PNEUMATIC CIRCUIT

PROBLEM

A double acting cylinder is to be actuated by a solenoid operated valve. When one push button is pressed the cylinder has to move forward and when another is pressed it has to retract. Design a circuit.

AIM

To design the above given circuit.

COMPONENTS REQUIRED

1. Double acting cylinder 12. 4/2 double solenoid DC valve 13. FRL unit 14. Fittings and Hoses Required quantity5. Required electrical components

CIRCUIT DESCRIPTION

Air from FRL unit is given to the DC valve. Two pressure ports of the valve are connected to the two ports of the cylinder. Individual solenoid is energized by pressing separate push buttons, as shown in the electrical circuit. In the normal condition the cylinder is in the retracted position. Circuit is operated by 24 V D.C power supply.


When the push button1is pressed, the solenoid A gets energized and the DC valve is moved to its actuated condition. The air from the valve goes to the cover end and the cylinder moves forward. Even after the push button is released and solenoid de-energized, since there is no spring to return, the valve and the cylinder remain at the same position. When the push button 2 is pressed, the solenoid B is energized and that side of DC valve comes into effect. This makes the cylinder to return. The next cycle starts when push button 1 is pressed.

RESULT

The given circuit is designed, constructed with the available components and tested successfully.

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Fig. 10 Electro Pneumatic Circuit

EX. NO. 11

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DESIGN OF CONTINUOUS CYCLE ELECTRO PNEUMATIC CIRCUIT

PROBLEM

Design a electro pneumatic circuit to operate a double acting cylinder continuously. The cylinder has to feed components to a punching machine. The operation should start when a start button is pressed and should over when a stop button is pressed.

AIMTo design a continuously operating electro pneumatic circuit with one pressing to start and one for stop.

COMPONENTS REQUIRED1. Double acting cylinder with magnetic sensor 12. 4/2 double solenoid DC valve 13. FRL unit 14. Fittings and Hoses Required quantity5. Required electrical components

CIRCUIT DESCRIPTIONThe magnetic sensor in the cylinder is use to sense the preset position of the piston. In this type of cylinders, the piston is having a magnet and the sensor is placed in the outside of the cylinder. If the magnetic piston reaches the sensor, it is sensed by the sensor and signal is given to the controller. It does the function external electrical limit switch. Air from FRL unit goes to the cylinder through the DC valve. In the electrical circuit, there is a normally open switch for start switch and a normally closed switch for stop. To hold the start signal a contact relay is use. At normal condition the cylinder is assumed to be in retracted condition and the magnetic sensor LS1 is closed also the DC valve assumes the corresponding position. The circuit is controlled by 24 V D.C.

WORKING OF THE CYLINDERWhen the start switch is pressed, power goes to the solenoid A through the NC stop valve and NO limit switch LS1 (magnetic sensor). Solenoid A gets energized and the cylinder moves forward. At the same time, the contact relay which is connected parallel to the solenoids, get energized and permanent start contact is made, even after start switch is released. As soon as the piston moves from the home position, the magnetic sensor does not sense and get open i.e. the LS1 in the circuit gets open. Due to this the power going to the solenoid stops. At the end of the forward stroke, the magnetic sensor 2 (LS2) senses the piston and closes. This makes the solenoid B to get energized and the cylinder moves back. When cylinder returns back fully, LS1 gets closed and piston starts moving forward. This cycle continues until the stop switch is pressed. When the stop switch is pressed, the power supply to the solenoid gets disconnected and at the same time the contact relay also deenergised. This leads to stoppage of power supply to the circuit until start switch is pressed.

RESULTGiven circuit is designed, constructed and checked successfully.

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Fig. 11 Continuous Cycle Electro Pneumatic Circuit

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EX. NO 12DESIGN OF PLC CONTROLLED ELECTRO PNEUMATIC CIRCUIT

PROBLEM

Design a PLC controlled circuit to activate a piercing cylinder. The cylinder has to be activated only if the work piece is sensed by the three sensors. If any two of the three sensors sense the presence of the work part, the piercing cylinder can be activated.

AIMTo design a circuit to activate a cylinder with PLC control.

COMPONENTS REQUIRED1. Double acting cylinder 12. 5/2 solenoid controlled pilot operated spring return valve 13. Sensors 34. PLC and required electrical cables 15. FRL unit 16. Fittings and Hoses Required quantity7. Electrical Power supply (24 volts)8. Interface box between PLC and sensors

CIRCUIT DESCRIPTION

The compressed air from the FRL unit is connected to the cylinder through the DC valve. The DC valve is operated by the pilot pressure which is controlled by the solenoid. The valve is spring return, so when the solenoid is energized, the valve actuated the piercing cylinder moves forward.

PLC PROGRAMME The inputs to the PLC are the output from 3 sensors. The inputs are named as I0.0, I0.1 and I0.2 respectively. The PLC output is taken in the port 0.0 and it is given to the solenoid. The programme is written in ladder logic in such a way that, if any two of the three inputs goes to PLC the output is got from the PLC.


When the work piece is placed in its position, if it is in correct position any two of the three sensors will sense the work piece and this is given as input to the PLC. Due to this an output is obtained from the PLC which energizes the solenoid. This leads to actuate the DC valve and finally the cylinder.

RESULT

The given circuit is designed, programmed and tried successfully.

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Fig. 12 PLC Controlled Electro Pneumatic Circuit

EX. NO. 13

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DESIGN OF SIMPLE HYDRAULIC CIRCUIT

PROBLEM

Design a hydraulic circuit for forward and return motion of a cylinder by manually operating a switch. The return stroke speed to be controlled.

AIM

To design a hydraulic circuit to create forward and return motion of a cylinder.

COMPONENTS REQUIRED

1. Double acting cylinder 12. 4/2 direction control valve 13. Flow control valve 14. Hydraulic power pack 15. Relief valve & Pressure gauge 1 each

CIRCUIT DESCRIPTION

The hydraulic circuit is designed with the components available in the hydraulic trainer kit. The double acting cylinder is connected to the direction control valve through hoses. The piston end of the cylinder is connected through the flow control valve to DC valve. The pump is connected to the DC valve through a termination block. Required pressure relief valve and pressure gauge are properly connected in the circuit.


Pressurized oil from the pump is given to the DC valve through the relief valve. If the manually operated valve is pressed, the oil flows to one side of the cylinder depending on the connection and the cylinder makes its movement. During return stroke the oil is allowed to come out through the flow control valve and this controls the speed (like meter out valve) of the cylinder in the return stroke.

RESULT


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Fig. 13 Simple Hydraulic Circuit

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EX. NO. 14HYDRAULIC CIRCUIT USING HYDRAULIC MOTOR

PROBLEM

Design a hydraulic circuit to operate hydraulic motor. The hydraulic motor is used to move an industrial winch, which is placed in a slope. The downward motion is caused by the clockwise movement of the motor and its speed should be controlled against the weight of the winch.

AIM

To design the above said circuit.

COMPONENTS REQUIRED

1. Hydraulic Bi-directional motor 12. Direction control valve (Double Solenoid) 13. Meter out valve 14. Hydraulic power pack and relief valve 1

CIRCUIT DESCRIPTION The two ports of the direction control valve is connected to the two input ports of the hydraulic motor. The valve used here is closed centre, solenoid operated string return 4/3 valve. The pressurized oil and tank are connected to the centre position of the DC valve. When one push button (PB1) is operated solenoid A is energized and when another push button (PB2) is pressed, solenoid B is energized. They generate clockwise and anticlockwise movement in the motor respectively. The pressure line is fitted with a relief valve for safety.


The pressurized oil from the pump initially goes to the DC valve and when the valve is in neutral position, oil cannot go anywhere because the valve is closed. So the pressure developed will be more than the set pressure of the relief valve and the oil will be relieved to the tank through relief valve. When PB1 is pressed, the solenoid A energizes and the oil go to the motor and create clockwise rotation in the motor. If the PB1 is released, then the spring takes the valve to its neutral position. Now the motion of the motor stops. When PB2 is pressed, the oil is directed by DC valve, in such a way that it creates anticlockwise rotation in the motor.

RESULT

Given circuit is designed, constructed and checked successfully.

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Fig. 14 Hydraulic Circuit using Hydraulic motor

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EX. NO. 15DESIGN OF SEQUENTIAL HYDRAULIC CIRCUIT

USING SEQUENTIAL VALVE

PROBLEM

Design a sequential hydraulic circuit: first cylinder A extends and then cylinder B. Cylinder A retracts and then Cylinder B. Use a sequential valve.

AIM

To design a circuit for the given sequence and to understand the working of sequential valve.

COMPONENTS REQUIRED

1. Hydraulic double acting cylinders 22. Directional control valve 13. Sequential valve 14. Hydraulic power pack 15. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

The output supply from the pump is given to the direction control valve. Required pressure relief valve is fitted to the circuit to avoid overloading the pump. One output port of the DC valve is connected to the cover end of cylinder A. Same output is connected to the cover end of Cylinder B through the sequential valve. Rod end of both the cylinders are connected in parallel to the other port of the DC valve. The DC valve is operated by electric power (solenoid) by pressing a switch.


The sequential valve will allow oil through it only after the certain preset pressure is built in the line. Until then the valve will not open and the oil will not flow to the further circuit. When the switch is pressed, solenoid got energized and the DC valve moves to its left configuration in working. The oil coming out of the valve first will be with lower pressure enough to move the cylinder A and insufficient to open the relief valve. So the cylinder A only will move forward and B will not. As soon A reaches it end of the stroke, since it cannot move further and pump is continuously pumping oil, pressure will build up in the line and after the preset value, sequential valve will open and the oil will flow to the cylinder B. After cylinder B reached the forward position. if the switch is released, the solenoid is disconnected from power and spring returns the DC value to its normal position. This leads the cylinders return back to the home position.

RESULT

The given circuit is designed, constructed with the available components and checked for working, and the working of sequential valve is understood.

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Fig. 15 Sequential Hydraulic Circuit using Sequence Valve

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EX. NO. 16DESIGN OF THREE CYLINDER SEQUENTIAL CIRCUIT

PROBLEM

Design a sequential circuit to give the following sequence. A+ C- B+ A- C+ B-. For starting every cycle of operation a manually operated valve to be actuated. The circuit needs to be controlled with pneumatic power.

AIM

To design a pneumatic circuit to give the above sequence with pneumatic control.

COMPONENTS REQUIRED

1. Double acting cylinder 32. Pilot operated 4/2 valve 33. Air supply & FRL unit 14. Manually operated 3/2 valve 15. Lever operated 3/2 valve 66. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

Three cylinders are named as A, B & C. The corresponding limit switches are a0 & a1, b0 & b1 and c0 & c1 for home and extended positions respectively. The directional control valves for each cylinder are named as X, Y & Z respectively and the cylinders are connected to them. The DC valves and individual limit switches are given with power from the FRL unit. The output from the limit switches are given as pilot to the DC valves, to make the respective cylinder to move. To have control on starting of the cycle (i.e. A+) the signal from the last actuated switch is given to the corresponding pilot through a manually operated spring return 3/2 valve, which works as a start switch. The output from each limit switch will create movement of cylinders as follows

a1 C-c0 B+b1 A-a0 C+c1 B-b0 A+ (Through manually operated valve)


Compressed air through FRL unit enters to the direction control valves and limit switches. At the home condition the cylinders A & B are at the retracted condition and the cylinder C is in the extended condition. So limit switches a0, b0 & c1 are in actuated condition and power comes to corresponding DC valves. The output from b0 is now available at starting valve. To start the cycle the starting valve is pressed for a while and released. If the starting valve is pressed the output from the valve goes to actuate DC value X which causes the cylinder A

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move forward. Now the limit switch a0 is released and at the end of the stroke limit switch a1 is pressed. This causes supply of pilot pressure to the DC valve Z and this causes the cylinder C to retract. This causes limit switch c1 released and at the end of the stroke, c0 is pressed. Air coming out of c0 is actuating the value Y and this causes the cylinder B to move forward. The forward motion of the cylinder B releases the limit switch b0 and at the completion of the stroke the switch b1 is actuated. This gives the pilot supply to valve X at the opposite side and this lead to the retraction of the cylinder A. At the end of the stroke the limit switch a0 is pressed and the value C is actuated to move the cylinder C forward. This, at the end of the stroke presses the limit switch c1 and this leads to the movement of cylinder backwards which is the last stroke of the cycle. At the end of the cycle the limit switch b0 is pressed and the power comes to the manually operated valve. As the manually operated valve is returned back to the closed position by the spring after the hand pressure is released, the cycle stops here waiting for another pressing of the start switch to start the next cycle.

RESULT


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EX. NO. 17DESIGN OF SEQUENTIAL CIRCUIT USING CASCADE METHOD

PROBLEM

Two cylinders are used to unload the part from chute of a machine to a conveyor. The cycle required is the Cylinder A moves forward and B moves forward. Then B returns back and A returns back (A+ B+ B- A-). Every cycle should start only after a manual valve is pressed.

AIM

To design a circuit using CASCADE method, for the given sequence.

COMPONENTS REQUIRED

1. Double acting cylinders 22.4/2 Pilot operated DC valve 33.3/2 manually operated valve 14.3/2 Lever operated valve (spring return) 4(limit switch)5. FRL unit 16. Fittings and Hoses Required quantity

CIRCUIT DESCRIPTION

Two cylinders and their respective limit switches are placed in the required places. The cylinders are named as A and B and the respective limit switches are named as a0, a1 and b0, b1 respectively. Two 4/2 DC valves direct the air to the cylinders. One 4/2 DC valve is used as group change valve. The manual valve is connected to start every cycle as shown. The given sequence is divided into tow groups and the group change valve is introduced in the appropriate place. The limit switches, group change valve and DC valves get power from the FRL unit .In the home condition, the limit switches a0 and b0 are pressed. One output port of the group change valve is closed because of not required.


When the manually operated valve is pressed, pilot supply goes to the DC valve of A and it moves forward. When a1 is pressed the output goes as the pilot of DC valve B and it moves forward. When b1 is pressed the output goes to actuate the group change valve. Due to the group change, the pilot signal going to B+ side of the DC valve is cut and B-side is activated .This leads to the return of the cylinder B and when b0 is pressed it gives pilot for A-. As a0 is pressed, it changes the group valve to its original position and the signal wait for the next pressing of manual valve for the start of next cycle.

RESULT

Given circuit is designed, constructed and checked successfully.

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EX. NO. 18

DESIGN OF AND / OR LOGIC FUNCTIONS

PROBLEM

A Machine clutch operated by a pneumatic cylinder will engage when cylinder moves forward. The cylinder should move forward either if two push buttons are pressed simultaneously or a remotely operated push button is pressed. Design the circuit.

AIM

To construct AND / OR logic functions circuits.

COMPONENTS REQUIRED

1. Double acting Cylinder 12. AND Valve 13. OR Valve 14. 4/2 DCV 15. Push button DCV 36. FRL Unit 1

DESCRIPTION

The input from the compressor is given to the FRL unit to get desired pressure level. Then it is connected to input of directional control valve, Push buttons. The output of two push button is connected to AND valve and output of AND valve is given to the input of OR valve and another input is from the push button. Output of OR valve is given to the directional control valve. The two ends of double acting cylinder is connected to directional control valve.

WORKING

When both the push button of AND valve is pressed, then only we get the extension and retraction of the cylinder. Where as in the case of OR valve, one push button is pressed which is enough for the getting the extension and retraction of the cylinder.

RESULT

Thus the logic AND and OR circuit were constructed and verified.

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Fig. 18 AND / OR logic functions circuit

EX. NO. 19

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DESIGN AND SIMULATION OF FLUID POWER CIRCUITSUSING FLUID SIM – P SOFTWARE

AIM

To simulate the given Circuit using Fluid Sim P Software

SOFTWARE REQUIRED

Fluid Sim P simulation Software

PROCEDURE

1. The required components are taken from the component window

2. It is done by just dragging the corresponding component and place it in the simulation

window

3. Connect the components by clicking the corresponding

4. Then Simulate the circuit

5. If there is any error, it does not simulate

RESULT

Thus the given circuit was designed and simulated using Fluid Sim P Simulation Software

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Fig. 19 Simulation of Sequential circuit using FluidSIM – P Software

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EX. NO. 20

STUDY AND ANALYSIS OF HYDRAULIC SYSTEM MODEL USING MATLAB SOFTWARE

AIM:

To study and analysis of hydraulic system model using MATLAB software.

SOFTWARE USED:

MATLAB 7.0

PROCEDURE:

1. Open MATLAB software in computer2. Click start button which is available in left bottom side of the window and select

simulink in the pop-up menu.3. In simulink select demos.4. In simulink demos select automotive or aerospace.5. In that, open hydraulic system models. A single hydraulic cylinder model will be

displayed in the window.6. The model consists of pump, control valve orifice area, control valve, cylinder, and

piston and spring assembly.7. By double clicking every component in the model, the parameters of that component

can be changed.8. Double click on the pump and change time and pump flow values according to the

need and run the simulation for 0.1 seconds.9. Take the output characteristics of single cylinder model obtained from the simulation.10. The characteristics of flow control valve and cylinder also can be changed in the same

way and do it if necessary.11. By selecting the 4 cylinder model icon, 4 cylinder models can be opened in new

window and necessary parameter input can be given to make simulation.12. By selecting the 2 cylinder model icon, which can be opened in new window and

study can be done.

RESULT:Thus the analysis of hydraulic system model using MATLAB for a given set

of parameters was studied and output characteristics of the given model were taken by simulation.

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Fig. 20 Hydraulic cylinder model

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Figure: Pressure Variation

Figure: Piston Position

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EX. NO. 21 MEASUREMENT OF PRESSURE USING LAB VIEW 8.2

AIM:To measure the pressure variation using pressure sensor and display the result through

lab VIEW 8.2

APPARATUS REQUIRED i) Pressure sensorii) Compressoriii) Flow control valveiv) Data cablev) Interfacing unitvi) Power cable

SOFTWARE REQUIREDLab view 8.2

PROCEDURE 1. Fix the pressure sensor in the compressed air tube line.2. Connect flow control valve in the same line. Using this valve we can very the

pressure level.3. Connect the output terminal of the pressure sensor to interfacing unit any one

of the channel (CH0 – CH7) 4. Connect interfacing unit which with computer through data cable5. Configure and test interfacing unit.6. Open new blank [Two window (front panel and block diagram) opened]7. Make program is block diagram window.

PROGRAM1. Create DAQ assistant [Block Diagram: Functions – Express – input DAQ assistant] and follow instructions. 2. Create indicator for displaying the voltage depends on the value of the

pressure [front panel: control numeric – indicator for DAQ assistant]3. Repeat same procedure to create more indicators for displaying pressure in bar. [Front panel: control numeric – numeric indicator]4. Create write measurement file [Block diagram functions – file I/O – write

measurement file / for saving data.5. Create stop control through while loop functions [Block diagram: functions –

structure – while loop]6. Create control by right clicking loop condition in while loop.7. End of program and save it.

RESULT:

Thus the pressure variation is measured using pressure sensors and the results were displayed through Lab VIEW software.

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Fig. 21 LabVIEW block diagram for pressure measurement

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Tabulation:

Sl. No.Time(Sec)

Pressure(Bar)

1 5 3.02 10 3.253 15 3.754 20 4.255 25 4.756 30 5.257 35 5.708 40 6.359 45 6.75

10 50 7.35

Model Graph:

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EX. NO. 22 MEASUREMENT OF TEMPERATURE USING LAB VIEW & 8.2

AIM: To measure the temperature using temperature sensor and display the result through lab view 8.2

APPARATUS REQUIRED:

(i) Thermocouple (J-type)(ii) Water bath (iii) Thermometer(iv) Interfacing unit (NI SCXI- 1000)(v) Thermocouple module (NI SCXI- 1112)(vi) Data cable(vii) Power cable

SOFTWARE REQUIRED: Lab view 8.2

PROCEDURE:(i) Insert thermocouple and thermometer into the water bath. (ii) Connect the output terminal of thermocouple to interfacing unit in any one of

the channel (CHO-CH2).(iii) Connect the interfacing unit with computer through data cable.(iv) Configure and test the interfacing unit.(v) Open new blank VI (Two windows (front panel and block diagram) opened)(vi) Make the program in block diagram window,

(a) Crate DAQ Assistant (Block diagram : functions-Express- Input-DAQ Assistant) and follow the instructions.

(b) Crate indicator (Front panel : Controls – Numeric – thermometer) for DAQ Assistant

(c) Crate another numeric indicator (Front panel : controls – Numeric – Numeric indicator) for displaying the temperature.

(d) Crate write measurement file (Block diagram : Functions – file I/O – write meas file) for saving the data.

(e) Crate stop control through while loop function (Block diagram : Functions – structures – while loop)

(f) Create control by right clicking loop condition in while loop.(g) End of the program and save it.

(vii) Switch ON the water bath.(viii) Run the program (→ Run)(ix) Save the data in particular location(x) Plot the graph between time and temperature using data.

RESULT:

Thus the temperature is measured using thermocouple sensor and the result were displayed through lab VIEW software.

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EX. NO. 23. MEASUREMENT OF AIR FLOW USING LAB VIEW 8.2

AIM:To measure the air-flow using air-flow sensor and display the result through lab

VIEW 8.2

APPARATUS REQUIRED i) Air flow sensorii) Bloweriii) Data cableiv) Interfacing unitv) Power cable

SOFTWARE REQUIREDLab view 8.2

PROCEDURE 1. Insert the air-flow sensor in the pipe duct of the blower 2. Connect the output terminal of the air flow sensor to interfacing unit any one of the channel (CH0 – CH7) 3. Connect interfacing unit which with computer through data cable4. Configure and test interfacing unit.5. Open new blank [Two window (front panel and block diagram) opened]6. Make program is block diagram window.

PROGRAMCreate DAQ assistant [Block Diagram: Functions – Express – input DAQ assistant]

and follow instructions. Create indicator [front panel: control numeric – indicator for DAQ assistant]Repeat same procedure to create more indicators for displaying air flow.[Front panel: control numeric – numeric indicator]Create write measurement file [Block diagram functions – file I/O – write

measurement file / for saving data.Create stop control through while loop functions [Block diagram: functions –

structure – while loop]Create control by right clicking loop condition in while loop.End of program and save it.

RESULT:Thus the air flow is measured using air flow sensors and the results were displayed

through Lab VIEW software.

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