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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
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