DESIGN AND FABRICATION OF PNEUMATIC

CONTROLLED RAMMING HOLDER

Submitted in the partial fulfillment of the requirement for the award of

“DIPLOMA IN MECHINCAL ENGINEERING”

SUBMITTED BY:

1. K.C PRASANTH 28203942

2. M.PRATHAP 28203943

3. M.PRAVEEN KUMAR 28203944

4. S.PREM KUMAR 28203945

5. M.RAGHUL 28203946

6. R.RAJASEKAR 28203947

Under guidance of

MR. G.SRINIVASAN , D.M.E ,Lecturer of MechanicalDEPARTMENT OF MECHANICAL ENGINEERING

PALLAVAN POLYTECHNIC COLLEGE

KOLIVAKKAM – IYYENKARKULAM,

KANCHIPURAM 631 501

March 2007 -2010

PALLAVAN POLYTECHNIC COLLEGEKANCHIPURAM

DEPARTMENT OF MECHANICAL ENGINEERING

BONAFIDE CERTIFICATE

This is to certify that this Project work on

“ DESIGN AND FABRICATION OF PNEUMATIC CONTROLLED RAMMING HOLDER ”

submitted by _ _ _ _ _ _ _ _ _ _ _ _ _ . Reg. No. _ _ _ _ _ _ _ _ _ _ _ _

is a partial fulfillment for the award of

DIPLOMA IN MECHANICAL ENGINEERING

This is the bonafide record of work carried out by him under our

Supervision during the year 2009 – 2010

Submitted for the Viva - voce exam held on _ _ _ _ _ _ _ _ _ _ _ _

HEAD OF DEPARTMENT PROJECT GUIDE

EXTERNAL EXAMINER INTERNAL EXAMINER

PREFACE

PREFACE

All the students are imported with theoretical knowledge

and practice to some extend to boost their level of technical knowledge.

They are being imposed to do a certain project work which makes them to

recollect their theoretical Back ground. On various technical subjects such a

scheme was introduced for the students studied diploma course in

engineering by the DIRECTOR OF TECHNICAL EDUCATION Chennai

during 1973 – 1974.

A Project has to be selected by a group of student who will

design and fabricate the same with the guidance of the staffs of the

institution. In the process of doing several working processes and

assembling they encounter problems which may educate them in further

technical knowledge.

In addition to that fabrication of a certain assembly gives

through ideas to the students by which they can do better one at the next

time because of better planning and scheduling.

ACKNOWLEDGEMENT

ACKNOWLEDGEMENT

At the outset, we would like to emphasize our sincere thanks to the

Principal Mr.M.SHANKAR M.E, encouragement and valuable advice.

We thank our Esquired Head of Department Mr.V.DAMODARAM B.E,

or presenting his felicitations on us.

We are grateful on our Encourages Mr. G. SRINIVASAN D.M.E,

Lecturer of Mechanical for guiding in various aspects of the project making it a grand

success.

We also owe our sincere thanks to all staff members of the Mechanical

Engineering Department.

Ultimately, we extend our thanks to all who had rendered their

Co - operation for the success of the project.

CONTENTS

CONTENTS

Chapte

r No

TITLE Pag

e No

1. INTRODUCTION

2. SYNOPSIS

3. CONSTRUCTION

4. WORKING PRINCIPLE

5. MECHANICAL SPARE PARTS AND DETAILS

6. DESCRIPTION OF PNEUMATIC COMPONENTS

7. PNEUMATIC CIRCUIT DIAGRAM

8. ELECTRICAL PARTS DETAILS

9. ELECTRICAL CIRCUIT DETAILS

10. FINISHING AND PAINTING

11. ADVANTAGES AND LIMITATIONS

12. APPLICATIONS

13. COST ESTIMATION

14. PROJECT SCHEDULE

15. CONCLUSION

16. BIBLOGRAPHY

17. PHOTOGRAPHY

INTRODUCTION

INTRODUCTION

Various manufacturing processes are available for

producing a component with required shape. Casting is one of the processes

used for making component of complicated shapes in large numbers. The

parts obtained by pouring the molten metal into mould cavity and

solidification are known as castings.

The processes of making required shape in molding sand

with the help of a pattern is known as MOULDING. The cavity produced

by moulding is known as mould or mould cavity. The place where

moulding, melting and casting are done is known as foundry.

RAMMER:

Rammer is used for packing or ramming the moulding

sand into the moulding box. It is made of wood or cast iron. It has a butt

end and a peen end. The butt end is in cylindrical shape and the peen end is

in the wedge shape.

SYNOPSIS

SYNOPSIS

To increase the productivity and to overcome skilled

labor shortage, most of the manufacturing industries are going for automation. The

main arm for us to select the project work is to acquire practical knowledge in the field

of automation using PNEUMATIC SYSTEM.

We selected “DESIGN AND FABRICATION OF

PNEUMATIC CONTOLLED RAMMING HOLDER ” as our project work and we

used principles of Mechatronics in developing this project work, the ramming

mechanism is achieved by reciprocating the double acting cylinders which controlled

by single solenoid operated 5/2 way DC valve which is actuated through the relays

and timers.

The operating pressure required for this system is 5 to 6 bar. The

maintenance required for this system is less than the other systems.

CONSTRUCTION

Pneumatic Controlled Ramming Holder

CONSTRUCTION :

Ramming Head

Piston Rod

Piston

Cylinder Barrel

Coupler

Plastic Tube

Valve Connector

Cylinder Port – A

Cylinder Port – B

CONSTRUCTION DETAILS:

The double acting cylinder is clamped in the M.S.stand

which is screwed to the wooden plywood Board of size 600 x 450 mm .

The stand is made with the 25 mm x25 mm ‘L’ angle M.S. material. The

solenoid valve is fixed on the plywood board using a screw head bolts.

The cylinder port A, B is connected to the output of the

solenoid valve. The pressurized air from the compressor is connected to the

input of the solenoid valve.

The solenoid valve coil is operating at 230V AC which is

connected to the output of the relay and timers circuits.

The inlet of the solenoid valve is connected to the

Compressor tank through FRL unit after setting the pressure to 7 bar.

WORKING PRINCIPLE

WORKING PRINCIPLE:

The double acting cylinder is actuated by a 5/2 solenoid

operated directional control valve, which is controlled (ON &OFF) through

the Micro controller.

When the push button is pressed, then the signal is send to

the input of the control processor input, which actuate the 5/2 solenoid coil

which in turn actuate the valve position to direct the air to the cylinder. The

cylinder piston rod reciprocates to and front and the ramming action take

place. When the setting time is reached, the position of the valve changed

and piston will be move back to its initial position.

Here there is no mechanical or electrical timer is used to

return the piston. The same set up can be modified to any auto machine

application by simply changing the software program using programmer

kit.

MECHANICAL SPARE PARTS

DETAILS

MECHANICAL SPARE PARTS DETAILS

1. Double acting cylinder

2. Ramming head

3. Single solenoid valve

4. Pneumatic fittings

5. Pneumatic tubes

DESCRIPTION OF PNEUMATIC

COMPONENTS

DESCRIPTION OF PNEUMATIC

COMPONENTS:

1. Double acting air cylinder with piston arrangement.

2. Spool valve (2 position 5 ports valve)

3. Pneumatic fittings

a. Bulk head union

b. Flexible hoses

c. Air compressors

DOUBLE ACTING AIR CYLINDER WITH PISTON

ARRANGEMENT:

It consists of a piston inside a cylindrical housing called a

barrel. Attached to one end of the piston is a rod which the rod end has one

port. This rod end port is used for entrance of air and extends outside one

end of the cylinder. At another end is a port for exit of air.

Double acting cylinder can be extended and retracted

pneumatically. The smallest bore size of an double acting cylinder is 1 1/8

inch. The piston, which is made of ductile Iron, contains u-cup packing to

seal against leakage between the piston and barrel.

DIRECTING CONTROL VALVES:

A direction control valve is used to change the direction of

air flow as and when required by the system for reversing the machine tool

devices. A direction control valve may be classified, according to the

construction of the internal moving parts as

1. Rotary spool type

2. Sliding Spool type

3. Solenoid operated valves

SOLENOID OPERATED VALVES

Solenoid valves are electromechanical devices like relays

and contractors. A solenoid valve is used to obtain mechanical movement

in machinery by utilizing fluid or air pressure. The fluid or air pressure is

applied to the cylinder piston through a valve operated by a cylindrical

electrical coil.

The electrical coil along with its frame and plunger is

Known as the solenoid and the assembly of solenoid and mechanical valve

is known as solenoid valve. The solenoid valve is thus another important

electromechanical device used in control of machines.

Solenoid valves are of two types,

1. Single solenoid spring return operating valve,

2. Double solenoid operating valve.

In fig 1 is shown a single solenoid spring return

valve units de energized condition. The symbol for the solenoid and the

return are also shown. The solenoid valve is shown connected to the

cylinder to help readers understand the solenoid valve action. In the de

energized condition, the plunger and the valve spool position as shown in

figure

5/2 way valve

In this position of spool, port P is connected to port

A and port B is connected to tank or exhaust (i.e. atmosphere) if air is used.

Spring pressure (S) keeps the spool in this condition as long as the coil is de

energized. Fluid pressure from port P through port A is applied to the left

side of the cylinder piston. Thus the cylinder piston moves in the right

direction. Now when the solenoid coil is energized, plunger is attracted and

it pushes the spool against spring pressure.

In this position of spool, port A gets connected to

tank and port P gets connected to port B. Thus pressure is applied to the

cylinder piston from right and moves the piston rod to the left. At the same

time fluid in the other side is drained out to the tank. When the solenoid

coil is again de energized, the spring (S) will move the spool to its original

position as shown in figure 1. Thus, normally when the solenoid coil is de

energized the piston rod remains extended.

In figure 3 both the solenoids are de energized and

therefore the centering springs keep the spool in the position shown. In this

position of spool, pressure port P is connected to tank while port A and B

are closely by spool. No pressure is applied to either port A or port B. In

figure 4 is shown the spool position when solenoid A is energized.

Energisation of solenoid A attracts its plunger and the spool moves in right

direction compressing the right side centering spring.

In this condition port P is connected to port A and

port B is connected to tank (exhaust in case of air). Figure 5 shows the

valve with solenoid B energized. The plunger is attracted and in turn spool

moves towards the left, compressing the centering spring to the left. Now

pressure port P is connected to port B and port A is connected to tank or

exhaust. When the solenoid is de energized the spool returns to the original

position.

PNEUMATIC FITTINGS:

There are no nuts to tighten the tube to the fittings as in the

conventional type of metallic fittings. The tube is connected to the fitting

by a simple push ensuring leak proof connection and can be released by

pressing the cap and does not require any special tooling like spanner to

connect (or) disconnect the tube from the fitting.

SPECIFICATION OF THE FITTING:

Body Material - Plastic

Collect/Thread Nipple - Brass

Seal - Nitrate Rubber

Fluid Used - Air

Max. Operating Pressure - 7 Bar

Tolerance on OD of the tubes - 1 mm

Min.Wall thickness of tubes - 1 mm.

FLEXIBLE HOSES:

The Pneumatic hoses, which is used when pneumatic

components such as actuators are subjected to movement. Hose is

fabricated in layer of elastomer or synthetic rubber, which permits

operation at high pressure. The standard outside diameter of tubing is 1/16

inch. If the hose is subjected to rubbing, it should be encased in a

protective sleeve.

PNEUMATIC CIRCUIT DIAGRAM

PNEUMATIC CIRCUIT DIAGRAM FOR PNEUMATIC RAMMING HOLDER

ELECTRICAL PARTS DETAILS

POWER SUPPLY UNIT

INTRODUCTION:

All the electronic components starting from diode to Intel

IC’s only work with a DC supply ranging from +5V to +12V. We are

utilizing for the same, the cheapest and commonly available energy source

of 230V-50Hz and stepping down, rectifying, filtering and regulating the

voltage.

STEP DOWN TRANSFORMER:

When AC is applied to the primary winding of the power

transformer, it can either be stepped down or stepped up depending on the

value of DC needed. In our circuit the transformer of 230V/15-0-15V is

used to perform the step down operation where a 230V AC appears as 15V

AC across the secondary winding. Apart from stepping down voltages, it

gives isolation between the power source and power supply circuitries.

RECTIFIER UNIT:

In the power supply unit, rectification is normally achieved

using a solid state diode. Diode has the property that will let the electron

flow easily in one direction at proper biasing condition.

Then AC is applied to the diode, electrons only flowwhen

the anode and cathode is negative. Reversing the polarity of voltage will

not permit electron flow. A commonly used circuit for supplying large

amounts of DC power is the bridge rectifier. A bridge rectifier of four

diodes (4 x IN4007) are used to achieve full wave rectification. Two

diodes will conduct during the negative cycle and the other two will

conduct during the positive half cycle, and only one diode conducts.

At the same time one of the other two diodes conducts for

the negative voltage that is applied from the bottom winding due to the

forward bias for that diode. In this circuit due to positive half cycle D1 &

D2 will conduct to give 0.8V pulsating DC. The DC output has a ripple

frequency of 100Hz. Since each alteration produces a resulting output

pulse, frequency = 2 x 50 Hz. The output obtained is not a pure DC and

therefore filtration has to be done.

The DC voltage appearing across the output terminals of

the bridge rectifier will be somewhat less than 90% of the applied rms

value. Normally one alteration of the input voltage will reverse the

polarities. Opposite ends of the transformer will therefore always be 180

degree out of phase with each other. For a positive cycle, two diodes are

connected to the positive voltage at the top winding.

FILTERING CIRCUIT:

Filter circuits which is usually capacitor acting as a surge

arrester always follow the rectifier unit. This capacitor is also called as a

decoupling capacitor or a bypassing capacitor, is used not only to ‘short’

the ripple with frequency of 120Hz to ground but also to leave the

frequency of the DC to appear at the output. A load resistor R1 is

connected so that a reference to the ground is maintained. C1, R1 is for

bypassing ripples. C2, R2 is used as a low pass filter, i.e. it passes only low

frequency signals and bypasses high frequency signals. The load resistor

should be 1% to 2.5% of the load.

1000f/25V: for the reduction of ripples from the pulsating.

10f/25V : for maintaining the stability of the voltage at the load

side.

0.1f : for bypassing the high frequency disturbances.

BLOCK DIAGRAM FOR POWER SUPPLY

STEP DOWN BRIDGE POSITIVETRANSFORMER RECTIFIER CHARGE

CAPACITOR

5V 12V REGULATOR REGULATOR

MOTHER DISPLAY BOARD BOARD RELAY

VOLTAGE REGULATOR:

The voltage regulators play an important role in

any power supply unit. The primary purpose of a regulator is to aid the

rectifier and filter circuit in providing a constant DC voltage to the device.

Power supplies without regulators have an inherent problem of changing

DC voltage values due to variations in the load or due to fluctuations in the

AC linear voltage. With a regulator connected to the DC output, the

voltage can be maintained within a close tolerant region of the desired

output. IC7812 and 7912 is used in this project for providing +12V and

12V DC supply.

SPECIFICATION:

Resistors R1 and R2 maintain line load regulation.

At the secondary side of the transformer, applied voltage = 15V

Conducting drop across the diodes = 2 * 0.6 = 1.2V

Without capacitor:

Vavg = (15-1.2)V = 13.8c pulsating DC

Frequency = 100Hz

With capacitor:

V = Vavg * 1.414 (form factor) = 19.51V

Frequency = 0 Hz

With 7812 voltage regulator:

V0 = +12V

With 7912 voltage regulator: V0 = -12V

ELECTRICAL CIRCUIT DETAILS

FINISHING AND PAINTING

FINISHING AND PAINTING

JOB PREPARATION:

Before welding, remove any bend in the L angle with

the sludge hammer on the anvil block. Then it is cut to the required length

with the hacksaw blade and fabricated to required dimensional shape with

arc welding.

FINISHING OPERATION BEFORE PAINTING:

After welding, any slag on the welded area is

removed with the chipping hammer and cleaned with the metal wire brush.

Then all the surfaces are rubbed with the emery sheet.

Metal primer is applied on the surfaces with the

brush .After drying the metal primer, the second coating is applied with the

paint.

ADVANTAGES AND LIMITATIONS

ADVANTAGES AND LIMITATIONS

ADVANTAGES:

The Pneumatic arm is more efficient in the technical field

Quick response is achived

Simple in constructions

Easy to maintain and repair

Cost of the unit is less when compared to other robotics

No fire hazard problem due to over loading

Comparatively the operation cost is less

The operation of arm is faster because the media to operate is air

Continuous operation is possible without stopping.

LIMITATIONS:

High torque cannot be obtained.

Load Carrying capacity of this unit is not very high (3 – 5 kgs).

While working, the compressed air produces noise, therefore a silencer may

be used.

APPLICATIONS

APPLICATIONS

DISCHARGE OF WORKPIECE:

The arm fed has wide application in low cost automation.

It can be used in automated assembly lines to pick-up the finished product

from workstation and place them in the bins. It can also be used to pick-up

the raw material and place them on the conveyor belts and vice versa.

JOB CLAMPING:

This unit can also be used in clamping operations in

certain areas of mass productions where clamping and unclamping have to

be done at high speeds. The applications of this unit is limited to

operations which involves moderate clamping forces.

TRANSFER OF JOBS BETWEEN WORK STATIONS:

The gripping method used in a low cost automation

to move the work piece from one workstation to another. The combination

of an angular rotary motion is the principle behind this method. The

gripper holds the work rigidly. The to and fro motion is achieved by means

of the actuating cylinder.

TOOL CHANGING APPLICATION:

When the pneumatic arms are made smaller in size they

can be used in automatic tool changer in CNC turning and drilling

machines, by attaching suitable tool holding device to the rotary cylinder.

COST ESTIMATION

COST ESTIMATION

NAME OF THE PARTS Cost in Rs

1. Double acting cylinder

2. Solenoid 5/2 way Valve

3. Relay

4. Transformer

5. RAMMING HEAD

6. Valve Connector (5Nos. x 40.00)

6. Plastic tube (5 meters) 25/metre

7. Electrical Box

8. Report

9. Transport Cost

1500/-

2000/-

500/-

500/-

300/-

200/-

250/-

500/-

750/-

250 x 3

10.Painting Cost

TOTAL

1250/-

--------------------

8,500/-

CONCLUSION

CONCLUSION We make this project entirely different from other projects.

Since concepts involved in our project is entirely different that a single unit

is used to various purposes, which is not developed by any of other team

members.

By doing this project we gained the knowledge of

pneumatic system and how automation can be effectively done with the

help of pneumatic system.

It is concluded that any automation system can be done

with the help of micro controller & pneumatic system.

We have successfully completed the project work on using

pneumatic control at our Institute.

By doing this project work, we understood the working

principle and uses of various controls, switches, relays etc.

It will be of no doubt that pneumatic system will be an

integrated part of any automation process in any industry.

Once again we express our sincere thanks to our staff

members.

BIBILOGRAPHY

BIBILOGRAPHY

1. Low cost automation with pneumatics - FESTO

2. Electro pneumatics - FESTO

3. Hydraulics & pneumatics for Power Production - Harry L Stewart

4. Basic pneumatics - FESTO

5. www.google.com

6. Workshop Technology - Hajra Chowdry

7. Production Technology - R.S. Khurmi

PHOTO VIEW

PHOTO VIEW