pneumatic sheet cutting machine

A PROJECT REPORT

ON

PNEUMATIC SHEET CUTTING MACHINE

A project report submitted in partial fulfillment of the requirement for the award of the

degree of B.Tech

BY

V V SAI PRADEEP 12JN1A0352

J JAWANTH SAI 12JN1A0309

K SAI TEJA 12JN1A0318

M DINESH 12JN1A0327

G JITHENDRA 12JN1A0313

Under the esteemed guidance of

P.VENKATESWARLU. M.Tech,(Ph.D)

SENIOR ASSISTANT PROFESSOR

DEPARTMENT OF MECHANICALENGINEERING

Department of Mechanical Engineering

SREE VENKATESWARA COLLEGE OF ENGINEERING: NELLORE

(Affiliated to JNTU Ananthapur, Anantapuram)

2015-16

DEPARTMENT OF MECHANICAL ENGINEERING

SREE VENKATESWARA COLLEGE OF ENGINEERING: NELLORE (Affiliated to JNT University, Anantapur, Anantapuram)

CERTIFICATE

This is to certify that this Project Report entitled “PNEUMATIC SHEET CUTTING

MACHINE” being submitted by




M DINESH 12JN1A0327


In partial fulfillment of the requirement for the award of the degree of BACHELOR OF

TECHNOLOGY in MECHANICAL ENGINEERING to Jawaharlal Nehru Technological

University, Anantapur, a record of bonafide work carried out under my guidance and

supervision. The results embodied in this project have not been submitted to any

other University or Institute for the award of any degree

Signature of Project Supervisor Signature of Head of the Department

Prof. P.VENKATESWARLU, M. Tech, (Ph.D.), Prof. J.V.S. BHASKAR, M. Tech, (Ph.D.)

Project Guide Head of the Department

Department of Mechanical Engineering, Department of Mechanical Engineering,

Sree Venkateswara college of Engineering Sree Venkateswara college of Engineering

Nellore. Nellore.

Signature of External Examiner

DECLARATION

We hereby declare that the project report entitled, “DESIGN AND ANALYSIS OF

EXPLOSION PROOF COMPOSITE PROPANE CYLINDER” completed and

written by us has not been previously formed the award of any degree or

diploma or certificate.

Place:

Date:




M DINESH 12JN1A0327


ACKNOWLEDGEMENT

We take this opportunity to express our gratitude and deep sense of

indebtedness to our project guide Prof. P.VENKATESWARLU, M.Tech, (Ph.D.), and

Prof. J. V. S. BHASKAR, M.Tech, (Ph.D.), Head of the department of “MECHANICAL

ENGINEERING” the valuable guidance and his kind and whole hearted support to us.

We feel thankful to him for his innovative ideas, which lead to the successful

completion of our project work.

We owe our guidance, our beloved principal Dr.B.DATTARAYA SARMA,

M.Tech, Ph.D., for their timely help, encouragement and interest in this work.

We are thankful to our beloved chairman Dr.P.BABUNAIDU who took keen

interest and encouraged us I every effort throughout this course.

In conclusion, we express our sincere thanks to teaching staff, lab assistants,

classmates and friends who have helped us either directly in carrying out this project

work and especially to our parents who helped us thoroughly for shaping out the

things well in order.

PROJECT ASSOCIATES




M DINESH 12JN1A0327


LIST OF FIGURES

Name Page No.

1.4 (a) Pneumatic Cylinder 5

(b) Direction Control Valve 6

(c) Flow Control Valve 7

2.1 (a) 5/2 Foot control valve 9

(b) 5/2 Direction foot control valve 10

(c) Neutral Position 13

(d) Working Position 14

(e) Machine Figure 15

2.5 5/2 Solenoid Valve 28

4.1 (a) General Layout 38

(b) Machine at Position ‘A’ 39

(c) Machine at Position ‘B’ 41

(d) Machine at Position ‘c’ 42

5.1 Drawings

(a) Pneumatic Cylinder 49

(b) Hose Collar 50

(c) Reducer 51

6.2 (a) Cylinder 56

(b) Square 57

Photography 67

LIST OF TABLES

Tables Page No.

5.1 Heat Treatment Chart 48

7.2 (a) More Effective Methods and Reducing Cost 67

(b) Symbols, Activity and Results 68

7.3 Description of Activity 69

9.2 Material Cost 75

CONTENTS

1. Introduction 1

1.1 Literature Survey 2

1.2 Prior Concept 3

1.3 Neef for Automation 4

2. Components and Description 8

2.1 Components of Pneumatic Shearing Machine 8

2.2 Main Components of the System 16

2.2.1 Characteristics of Double Acting Compressor 19

2.3 Classification of Cylinders 21

2.4 Parts of Pneumatic Cylinder 23

2.5 Parts of a Solenoid Valve 27

2.6 Working of Solenoid Valve 30

3. Pneumatic System 33

3.1 Advantages of Pneumatic System over Other Systems 35

3.2 Specifications of Pneumatic Elements 35

4. Working Principle 37

5. Proposed Work 43

5.1 MACHINE CONSTRUCTION 41

6. Project Designs and Drawings 52

6.1 Requirement Analysis 52

6.2 Statement for Design 55

6.3 Pneumatic Cylinder 59

6.3.1 Design of Piston Rod 59

6.3.2 Design of Cylinder Thickness 61

6.3.3 Diameter of Piston Rod 62

6.3.4 Length of Piston Rod 63

7. Test Cases, Project Time Line & Task Distribution 64

7.1 Test Cases 64

7.1.1 Objectives 64

7.2 Task Distribution 66

7.3 Project Time Line 69

8. Advantages, Disadvantages and Applications 71

9. Cost Estimation 62

9.1 Introduction 72

9.2 Purpose of Cost Estimating 72

10. Conclusion and Future Scope 76

7.1 Conclusion 76

7.2 Future Scope 77

References 78

Photography 79

ABSTRACT

The sheet metal cutting process is a main part of the all industries.

Normally the sheet metal cutting machine is manually hand operated one for

medium and small scale industries. In our project is “PNEUMATIC AUTO

FEED SHEET METAL CUTTING MACHINE”.

Automation in the modern world is inevitable. Any automatic machine

aimed at the economical use of man, machine, and material worth the most. In

our project is solenoid valve is used for automation.

The sheet metal cutting machine works with the help of pneumatic

double acting cylinder. The piston is connected to the moving cutting tool. It is

used to cut the small size of sheet metal. The machine is portable in size, so

easy transportable.

Figure: Concept Image for Project

CHAPTER-1

Introduction

The formation of any business begins with someone producing the

initial idea for the project. The continued success of an established

business depends upon the number and quality of the ideas fed into it.

Without a continual flow of new ideas, a business cannot function

profitably or expand successfully and must, therefore eventually fade into

total obscurity.

Ideas for a new business project, a new product, a means of reducing

manufacturing costs or for solving industrial labor problems, begin in the

human mind. Most people conceive their ideas unconsciously, and

because they are unaware of the mental mechanics that caused the ‘idea’

to be produced, they cannot repeat the ideation process to produce

further profitable ideas at will.

Fortunately, there are available established creative techniques

which, when used correctly, do enable a person to produce a large number

of first-class ideas at will. One such creative technique, and probably the

most widely used in American industry, is ’brainstorming’.

1.1 Literature Survey:

In shearing or cutting operation as or blade descends upon the metal,

the pressure exerted by the blade first cause the plastic deformation of the

metal. Since the clearance between the two blades is very small, the plastic

deformation takes place in a localized area and the metal adjacent to the

cutting edges of the blade edges becomes highly stressed, which causes the

fracture to start on both sides of the sheet as the deformation progresses and

the sheet is sheared

Shearing machines are classified according to the following:-

1) Pneumatically Operated

2) Hydraulically Operated

3) Rack and Pinion Operated

4) Spring Operated

Brief descriptions of all the types are as follows –

Pneumatically Operated

Heart the advertisement of the header is carried out in the upward

and the downward direction using the pneumatic double acting piston

and cylinder unit arrangement along with the foot operated direction

control valve. In this type of machine high pressure air is used as the

working fluid for the transfer of power and the motion.

Hydraulically Operated

Hear the lowering and rising of the header is carried over using the

hydraulic piston and cylinder arrangement. To actuate the piston and

the cylinder, the oil is allowed to enter the cylinder from front or the back

side of the piston. But the oil is compositely costlier and its leakage may

cause so many problems.

Rack and Pinion Operated

Hear the lowering and rising of the header is carried out manually

using the rack and pinion management. In this case the required

pressure is applied manually using direct hand pressure on the rack

using pinion and leaver arrangement. Since the machine is robust and

requires large pressure, hence it is not suitable.

Spring Operated

The working of spring operated machine is similar to the rack and

pinion operated machine but differs from it in construction. Hear the

lowering and rising of the heating handle is carried out manually and it

requires too much pressure for its operation and also there is possibility

of having damage to the work piece if not handled carefully.

1.2 Prior Concepts:

Pneumatics, from the Greek (pneumatikos, coming from the wind) is the

use of pressurized gases to do work in science and technology.

Pneumatics was first documented by Hero of Alexandria in 60 A.D., but

the concept has existed before then. A pneumatic product represents a multi-

billion dollar industry today. Pneumatic devices are used in many industrial

applications .Generally appropriate for applications involving less force than

hydraulic applications and typically less expensive than electric applications,

most pneumatic devices are designed to use clean dry air as an energy source.

The actuators then convert that compressed air into mechanical motion. The

type of motion produced depends on the design of the actuator. Pneumatic is

employed in a variety of settings. In dentistry applications, pneumatic drills

and lighters, faster and simpler than a electric drill of the same power rating

(because the prime mover, the compressor, is separate from the drill and

pumped air is capable of rotating the drill bit at extremely high rpm).pneumatic

transfer system are employed in many industries to move powders and pellets.

Pneumatic tubes can carry objects over distances. Pneumatic devices are also

used where electric motors cannot be used for safety reasons, such as mining

applications where rock drills are powdered by air motors to preclude the need

for electric motors depends in the mine where explosive gases may be present.

1.3 Need For Automation:

Automation can be achieved through computers, hydraulics, pneumatics,

robotics, etc., of these sources, pneumatics form an attractive medium for low

cost automation. The main advantages of all pneumatic systems are economy

and simplicity. Automation plays an important role in mass production.

Reduction of lab our and material cost

Reduction of overall cost

Increased production

Increased storage capacity

Increased safety

Reduction in fatigue

Improved personnel comfort

1.4 Pneumatic Cylinder:

Pneumatic cylinder or air cylinders are mechanical devices used to

import a force from a fluid, typically compressed air –

Fig 1.4 (a): Pneumatic Cylinder

A typically pneumatic cylinder consists of a piston, piston rod, and a

body or tube. Compressed air enters at one end of the tube, importing force on

the piston, which is the displayed (movies) in order to balance the force exerted

on the piston. Air cylinders, or actuators as they are also called, are available

in the variety of sizes, shapes, and have varying strokes. Typical cylinder sizes

range from a small 2.5mmair cylinder, which might be used for picking up a

small transistor or other electronic component, to 400mm diameter air cylinder

which would impart enough force to lift a car.

Fig 1.4 (b): Direction Control Valve

Fig 1.4 (c): Flow Control Valve

CHAPTER-2

Components and Description

2.1 Components of Pneumatic Shearing Machine

Different components of pneumatically shearing machine are:-

1. Shearing Blade

2. Pneumatic Cylinder

3. 5/2 Direction control foot operated valve

4. Air circulating Device

5. Frame

Double Acting Cylinder:-

Hear we have used double acting cylinder. It is the pneumatic actuator, which is actuated using compressed air. The force exerted by the compressed

air moves the piston in two directions in a double acting cylinder. In principle, the stroke length is unlimited, although buckling and bending must be considered before we select a particular size of piston diameter, road length

and stroke length.

The double acting cylinder consists of

1. Cylinder tube,

2. Piston unit,

3. Double cup packing on piston, rod packing of O rings,

4. Bronze rod guide,

5. Piston rod,

6. End covers(flanges)

7. Port connection,

8. Cushion assembly.

The cylinder is manufactured from aluminum solid bar with central bore on

lathe machine. It is then made smooth internally using method of honing and

lapping. It contains piston and piston rod, which reciprocates to and fro with

the application of high pressure air. The piston is fitted with the piston ring

which is made of Teflon rubber to make perfect compression of the air. 5/2

Direction control foot operated valve:

Its basic symbol is as shown –

Fig 2.1 (a): 5/2 Foot control valve

Figure 2.1 (b): 5/2 Direction footcontrol valve

To control the to and fro motion of a pneumatic cylinder, the air energy

has to be regulated, controlled, and reversed with a predetermined sequence in

a pneumatic system. Similarly one has to control the quantity of pressure and

flow rate to generate desired level of force and speed of actuation.

To achieve these functions, valves are used to-

(I) Start and stop pneumatic energy,

(II) Control the direction of flow of compressed air,

(III) Control the flow rate of the compressed air,

(IV) Control the pressure rating of the compressed air.

A direction control valve has two or three working positions generally. They are:

1) Neutral or zero position

2) Working position

The positions are mostly numbered as 0, 1, 2. Direction control valves

are designated to indicate both the number of ways as well as the number of

working positions such as 4/2, 3/2, 5/2 means 5 ways /2positions.

Here the spool slides inside the main bore and according that the spool

position is made ON or OFF due to the fact that the spool gets connected to the

open side or the closed side of the air opening.

Air circulating devices:

The compressed air is stored in an air receiver from which air is drawn

out in to the consumer point by means of pipe line.

While laying out the pipe line for the system, one should take sufficient

care and pay attention to see that the pressure drop from the generating point

to the point of consumption remains as low as possible. For economical reason,

it is always better if the total drop of pressure is kept limited to a maximum

value of 0.1 bar or even less.

The following factors are taken into account while selecting pneumatic

pipeline and other air- line installations:-

1) Pressure of compressed air in the lines.

2) Total flow rate per unit time through the line.

3) Permissible pressure drops in the line.

4) Types of tube material and types of line fitting.

5) Length and diameter of tube or other pipelines.

6) Working environment.

Considered the above factors we have selected the flexible hose tubes of

1/8diameter.

Frame Base:

It forms the robust support to stand the machine vertically. It

holds the weight of the vertical post and supports the direction control valve. It

is made of mild steel channels of rectangular base with the vertical post and

the horizontal channel.

Shearing blade:

Shearing, also known as die cutting, is a process which cuts stock

without the formation of chips or the use of burning or melting. Strictly

speaking, if the cutting blades are straight the process is called shearing.

Figure 2.1 (c): Neutral Position

Fig 2.1 (d): Working Position

Fig 2.1 (e): Machine figure

2.2 Main Components of the System

The major components of these systems are,

Compressor

Pneumatic Cylinder

Solenoid Valve

Hose and fitting

Seals

Control Timer Circuit

Flow control valve

Compressor:

The air under high pressure is given by a compressor. It is driven

by an electric motor. The compressor delivers air to inlet of the cylinder.

An air compressor as the same indicates is a machine to compress the

air and to raise its pressure. The air compressor sucks air from the

atmosphere, compresses it and then delivers the same under a high

pressure to a storage vessel from the storage vessel it may be conveyed

by a pipeline to a place where the supply of compressed air is required.

Since the compression of air requires some work to be done on it,

therefore compressor must be driven by some prime mover.

The compressed air is used for many purposes such as for

operating pneumatic drills, rivets, paint spraying and supercharging of

internal combustion engines etc., It is also used in the operation of lifts,

rams, pumps and variety of other devices in industry. Compressed air is

sucked for producing ballast of air in blast furnaces and Bessemer

converter.

Classification of Air Compressor: The air compressor may be classified in many ways but the

following are important of view.

1. According to working

a. Reciprocating Compressor

b. Rotary Compressor

2. According to action

a. Single acting compressor

b. Double acting compressor

3. According to number of stages

a. Single stage compressor

b. Multi stage compressor

Reciprocating Compressor:

They are available in great variety including special machine for

unusual requirements Maximum compression ratio may be as high as 10

per stage. Two stage compressors are available for compression ratios

greater than eight.

There different type of piston type reciprocating air compressor are

available. They are

1. Vertical

2. Horizontal

3. Radial

The most commonly used one is horizontal air cooled type

reciprocating air compressor for a pressure range 6 to 12 Kg/cm².

Construction:

It is similar to that of an internal combustion (IC) engine consisting

of cost-iron or aluminum body with an oil tank, the base piston with

piston rings, valves, connecting rods, cranks, crank shaft and bearing

etc. If the piston is moving down air is sucked in through the suction

valve and a filter and is compressed in return stroke.

Oil level gauges, oil filling screw and oil outlet screw etc are also

important parts of an air compressor.

The pressure switch is connected to the driving motor and is set

such that it automatically trips off, disconnecting the electrical

connection to the motor as soon as the receiver achieves the desired set

pressure.

The safety valve is set to the same pressure limit and in case of the

pressure exceeds this limit, it automatically opens and excess pressure is

exhausted to the atmosphere, thus limiting the system pressure to the

desired level. The drain valve drains off the condensate produced at the

condenser and the receiver piston rings are used around the piston to

make it airtight.

The first stage cylinder is called the low-pressure cylinder (LP)

where air is drawn from the atmosphere and is compressed initially. The

second cylinder is called the second-stage cylinder, which is of smaller

diameter and it is also called high-pressure cylinder (HP). Here the

initially compressed air from first LP cylinder is further compressed to

high pressure.

When air is compressed, considerable heat is generated, this heat

must be dissipated at least in units, where pressure exceeds 2 bar. The

main machine is cooled by air circulation on water circulation.

2.2.1 Characteristics of Double acting compressors

For the same sped and cylinder volume, air delivery is double that

of a single acting compressor.

They are mostly suitable for large capacity.

Cylinders are mostly water-cooled.

They are normally used for continuous and heavy-duty works.

Higher speed of piston while reducing the size of the compressor

may contribute to greater wear of piston rings, cylinder liners and

pickings. Preferable range of piston speed advocated.

For small capacity compressor – 300 m/min

For large capacity compressor-25m/min

The ultimate choice of an air compressor is decided considering

two main factors. They are:

One should go for a small compressor for each machine

(or)

Should one have a centralized compressor “power

house?”

The portable answer will depend on pipe line layout, system

requirement and the distance of the user machine from the plant.

PNEUMATIC CYLINDER:

Cylinder is a device which converts fluid power into liner

mechanical force and motion. These cylinders are widely used in

industrial pneumatic systems. These cylinders are also called as linear

motors and reciprocating motors pneumatic cylinders are designed for a

variety of services.

Pneumatic cylinders are designed for a variety of services.

Pneumatic cylinders transforms the flow of pressured fluid into a push or

pull of the piston rod since out system uses double acting cylinders we

shall see some details about them.

Double acting cylinders are in one in which fluid force can be

applied to the movable element in two directories. The force exerted by

the compressed air moves the piston in two directories in a double acting

cylinder. They are used particularly. The piston is required to perform

work not only on the advance movement but also on the return. In

principle, the stroke length is unlimited, although bucking and bending

must be considered before we select a particular size of piston diameter,

rod length and stroke length.

The main component of any pneumatic system is the cylinder,

which receivers air under pressure and the pressurized air helps to move

the piston to and fro. The force acting on the piston will be equal to the

product of the pressure of air and the area of the cylinder.

The amount of air delivered into the cylinder into the cylinder

decides the rate of doing work. A cylinder is a hollow circular section

with the top and bottom flange provided to prevent the leakage of air.

The compressed air is used to actuate the piston. In order to move

the piston to and fro, the air is supplied to the top and bottom of the

cylinder alternatively.

2.3 Classification of Cylinders

Cylinder is mainly classified into two types namely,

Single acting cylinder.

Double acting cylinder.

Single acting cylinder:

In single acting cylinder, using the spring provided around the

piston rod attains the return stroke, but it is not efficient. So, the double

acting cylinder is used in which the return stroke is attained using

compressed air.

Double Acting Cylinder:

In this the force exerted by the compressed air moves the piston in

two directions. They are used partially when the piston is required to

perform work not only on the advance movement but also on the return

stroke. This principle, the stroke length is unlimited, although bucking

and bending must be considered before selecting the particular size of

piston diameter, rod length and stroke length.

The different parts of double acting cylinder are:

1. Barrel

2. Piston rod

3. Top Cover

4. Bottom Cover

5. Wiper Cover

6. Retaining ring

7. Piston

8. Piston guide

9. Bearing Cap

10. ‘O’ ring for piston guide

11. Hexagonal socket head screw

12. Check nut

The double acting cylinder is made up of cast aluminum. The

inner and outer surface of the cylinder should be machined accurately.

The internal diameter of the cylinder should be accurate in order to

provide a smooth surface for the packing. The appearance of the outer

diameter should be good.

The outer most part of the bottom and top cover contains internal

threads for inserting bolts to clamp the cylinder.

In case of double acting cylinder a force is developed in both the

directions. The moving member inside the cylinder is nothing but a

piston which is found to be moving forward and backward due to high-

pressure air. The cylinder top and lower plate are flanged together by

means of bolts and

nuts. The bottom of the cylinder is also flanged with end covers for the

movement of the piston in reciprocating manner.

The bottom end cover has a bore in center whose diameter is

slightly larger than piston rod diameter. The force during the return

stroke is less compared to that of the forward stroke because in the

former, the piston rod covers some area so that the air cannot

concentrate in the piston rod area.

2.4: Parts of Pneumatic Cylinder

Piston:

The piston is a cylindrical member of certain length which

reciprocates inside the cylinder. The diameter of the piston is slightly

less than that of the cylinder bore diameter and it is fitted to the top of

the piston rod. It is one of the important parts which convert the

pressure energy into mechanical power.

The piston is equipped with a ring suitably proportioned and it is

relatively soft rubber which is capable of providing good sealing with low

friction at the operating pressure. The purpose of piston is to provide

means of conveying the pressure of air inside the cylinder to the piston of

the oil cylinder.

Generally piston is made up of

Aluminium alloy-light and medium work.

Brass or bronze or CI-Heavy duty.

The piston is double acting type. The piston moves forward when

the high-pressure air is turned from the right side of cylinder. The

piston moves backward when high pressure acts on the piston from the

left side of the cylinder. The piston should be as strong and rigid as

possible.

The efficiency and economy of the machine primarily depends on

the working of the piston. It must operate in the cylinder with a

minimum of friction and should be able to withstand the high

compressor force developed in the cylinder and also the shock load

during operation.

The piston should posses the following qualities.

a. The movement of the piston not creates much noise.

b. It should be frictionless.

c. It should withstand high pressure.

Piston Rod:

The piston rod is circular in cross section. It connects piston with

piston of other cylinder. The piston rod is made of mild steel ground and

polished. A high finish is essential on the outer rod surface to minimize

wear on the rod seals. The piston rod is connected to the piston by

mechanical fastening. The piston and the piston rod can be separated if

necessary.

One end of the piston rod is connected to the bottom of the piston.

The other end of the piston rod is connected to the other piston rod by

means of coupling. The piston transmits the working force to the oil

cylinder through the piston rod. The piston rod is designed to withstand

the high compressive force. It should avoid bending and withstand

shock loads caused by the cutting force. The piston moves inside the rod

seal fixed in the bottom cover plate of the cylinder. The sealing

arrangements prevent the leakage of air from the bottom of the cylinder

while the rod reciprocates through it.

Cylinder Cover Plates:

The cylinder should be enclosed to get the applied pressure from

the compressor and act on the pinion. The cylinder is thus closed by the

cover plates on both the ends such that there is no leakage of air. An

inlet port is provided on the top cover plate and an outlet ports on the

bottom cover plate. There is also a hole drilled for the movement of the

piston.

The cylinder cover plate protects the cylinder from dust and other

particle and maintains the same pressure that is taken from the

compressor. The flange has to hold the piston in both of its extreme

positions. The piston hits the top plat during the return stroke and hits

the bottom plate during end of forward stroke. So the cover plates must

be strong enough to withstand the load.

Cylinder Mounting Plates:

It is attached to the cylinder cover plates and also to the carriage

with the help of ‘L’ bends and bolts.

Control Valve:-

Various types of control valves are used to regulate, control and

monitor the air energy for control of direction pressure, flow, etc.

Pneumatic energy is regulated and controlled by pneumatic valves.

Functionally valves are divided into four major groups.

Direction Control

Flow Control

In our project electrically actuated solenoid operated 5/2 DC valves are

used.

Solenoid is another name for an electromagnet. Direction control

valves are very often actuated by electromagnets. An electromagnet is a

temporary magnet. A magnetic force is developed in an electromagnet

when electrical current passes through it and force drops down as soon

as it is de energized.

This electromagnet is commonly termed as solenoid. The proper

working of a solenoid operated valve depends on the reliability of the

electromagnets.

It ensures

Quick and sure action

Long life.

Easy maintenance.

Less wastage of energy.

Solenoid Valve:

The directional valve is one of the important parts of a pneumatic

system. Commonly known as DCV, this valve is used to control the

direction of air flow in the pneumatic system. The directional valve does

this by changing the position of its internal movable parts.

This valve was selected for speedy operation and to reduce the

manual effort and also for the modification of the machine into automatic

machine by means of using a solenoid valve. A solenoid is an electrical

device that converts electrical energy into straight line motion and force.

These are also used to operate a mechanical operation which in turn

operates the valve mechanism.

Solenoids may be push type or pull type. The push type solenoid is

one in which the plunger is pushed when the solenoid is energized

electrically.

2.5 Parts of a Solenoid Valve

1. Coil:

The solenoid coil is made of copper wire. The layers of wire are

separated by insulating layer. The entire solenoid coil is covered with an

varnish that is not affected by solvents, moisture, cutting oil or often

fluids. Coils are rated in various voltages such as 115 volts AC, 230

volts AC, 460 volts AC, 575 Volts AC, 6 Volts DC, 12 Volts DC, 24 Volts

DC, 115 Volts DC & 230 Volts DC. They are designed for such

frequencies as 50 Hz to 60 Hz.

2. Frame:

The solenoid frame serves several purposes. Since it is made of

laminated sheets, it is magnetized when the current passes through the

coil. The magnetized coil attracts the metal plunger to move. The frame

has provisions for attaching the mounting. They are usually bolted or

welded to the frame. The frame has provisions for receivers, the plunger.

The wear strips are mounted to the solenoid frame, and are made of

materials such as metal or impregnated less fiber cloth.

3. Solenoid Plunger:

The Solenoid plunger is the mover mechanism of the solenoid. The

plunger is made of steel laminations which are riveted together under

high pressure, so that there will be no movement of the lamination with

respect to one another. At the top of the plunger a pin hole is placed for

making a connection to some device.

Solenoid operated valves are usually provided with cover over

either the solenoid or the entire valve. This protects the solenoid from

dirt and other foreign matter, and protects the actuator. In many

applications it is necessary to use explosion proof solenoids.

2.6 Working of Solenoid Valve

The solenoid valve has 5 openings. This ensure easy exhausting of 5/2

valve. The spool of the 5/2 valve slide inside the main bore according to

spool position; the ports get connected and disconnected. The working

principle is as follows.

Position-1

When the spool is actuated towards outer direction port ‘P’ gets

connected to ‘B’ and ‘S’ remains closed while ‘A’ gets connected to ‘R’

Poisition-2

When the spool is pushed in the inner direction port ‘P’ and ‘A’ gets

connected to each other and ‘B’ to ‘S’ while port ‘R’ remains closed.

House and Fittings:

It is provided for the passage of compressed air from the

compressor outlet to the operating valve.

Two separate pipes also connect the operating valve with the

working cylinder pressure drop through and air line depends on the flow

rate, pipe diameter, and pipe length and pipe geometry. It can be

determined directly for straight pipes of any given length. A small

chaining bore size can have marked effect on pressure drop, where as

even doubling the pipe length, will only result in doubling the pressure

drop.

Pressure drop through bends and fittings can only be determined

by empirical tests, since it is specific to the internal geometry involved.

Rigid pipes however are less manipulated through remain form of bends

with arrangements increase and variable air have to flow and the flow

itself may be of fluctuating or pulsating nature. In this case it is thus

normally based on practical recommendation.

Seals:

Seal is an important component of a pneumatic system and is used

to prevent the air leakage through the joint.

This project passes the static seal which are used to prevent the

leakage through the stationary surface.

Material of the seal is Teflon tape. Teflon has the following

properties

Withstand the system pressure and temperature

without any damage.

Resist the wear and abrasion.

Recover from deformation.

Resists the adverse effects such as deterioration and

shrinking caused by the system air.

Seals are devices for closing gaps to prevent leakage or make

pressure joints and also to prevent the entry of air and dirt from outside

into the system. The material of seal must be compatible with the fluid

medium. It is a circular ring made of synthetic rubber. It is used for

providing tight sealing between the piston and the cylinder wall. It

prevents air leakage from the top and bottom of the cylinder.

Seals for air cylinder and valves are not normally called upon to

seal pressure higher than about 2 bars. Since the fluid to be seated is a

gas, (in our case air) rubbing speeds tends to be high and the seal the

seal may have to be operated under dry conditions with minimal

lubrication.

Flow Control Valve:

Flow Control Valves are fitted to all the distribution tubes. This

valve is made of brass. Both the ends have stepped surface to insert

hoses. A handle is provided to control the flow of oil in every valve.

(a) Technical Data:

Size : ¼”

Pressure : 0 to 10 kg / cm2

Media : Air

(b) Purpose:

This valve is used to speed up the piston movement and also it acts as

an one – way restriction valve which means that the air can pass through only

one way and it can’t return back.

CHAPTER-3

Pneumatic System

The subject of pneumatics might probably be termed as compressible

fluid mechanics. It deals with the use of pressurized gas as a source of

power. The pressure energy of gas is directly converted into force to do

the required work with high efficiencies of conversion.

The pneumatic cylinder utilizes a low pressure fluid. It has the

advantage that cylinder construction can be simplified reducing cost. It

can be used for high speed operations.

Pneumatics is widely associated with low cost automation. It

generally offers the lowest initial and operating cost and simple, flexible

control systems.

Though pneumatic system is the study properties of air other

gases, we are concerned with the study of air.

Characteristics of Compressed Air:

The greatest advantage of pneumatic system is the availability of

working medium free of cost and it plentiful. Compressed air can also be

transported easily and can be easily stored in a reservoir. Another

notable advantage is the insensitiveness of compressed air to

temperature fluctuations. It ensures reliable operation even under

extreme conditions of temperature. Compressed air offers no risk of

explosion; hence no expensive protection cost is required.

Characteristics of Pneumatics:

1. Compressibility:

A pneumatic fluid is compressible. Compressibility plays a major

role in the actuation of piston, i.e., opening a valve does not move the

piston immediately, rather sufficient fluid must flow into the volume to

increase the pressure until the force overcomes that on the other side.

Compressibility is the energy storage of a fluid. As it is possible to

store compressed fluids and transport them, pneumatics has the

advantage of transportability. Another advantage of the energy storage

capacity is the small compressor charging a tank can supply a system

having high peak loads but small average loads.

2. Leakage Sealing Problems:

Several methods are used to minimize leakage. One is to use a low

operating pressure. Another method to prevent leakage is sealing. Good

sliding and rotating sealing are to obtain in pneumatics is because of low

viscosity of the fluids Diaphragms and bellows are used to avoid sliding

seats.

3. Low Viscosity:

A highly encounted problem due to low viscosity is that of sealing.

They provide less viscous damping due to low viscosity hence sliding

parts wear considerably. This adds the necessity for external sources of

lubrication. Another problem is that the pneumatic cylinder should be

thinner enough to maintain a laminar flow inside.

3.1. Advantages of Pneumatic System over Other

System:

1. Output power of the pneumatic system can be easily controlled

2. Pneumatic system is not affected by over loading

3. The pneumatic system can be used at various working temperature

4. Air can be easily distributed through pipelines over very long

distances

5. Pneumatic enables high working speeds

6. It is a maintenance free system

7. Pneumatic enables the application of force very gently which is not

only beneficial to pneumatic components but also the equipment

which they are installed.

8. The working fluid which is stored in the storage tank can be taken

through number of lines which eliminates the use of individual

power sources say electric motor and many other machine parts.

3.2. Specifications of Pneumatic Elements:

The various pneumatic elements are specified according to different

standards. The standard varies depending upon the manufacturers.

1. Double acting Cylinder:

Stroke length = 50 mm

Piston Diameter = 40 mm

Maximum Operating Pressure = 12 bar

Temperature range = 120C to +80C

Material = Aluminum alloy

Seals = Polyurethane

O’ ring = Nitrile

2. Solenoid Directional Control valve:

We have used 5/2 solenoid valve as the directional control valve.

Voltage = 230 volts

Frequency = 50 Hz

Maximum Operation Pressure = 10 bar

Port size = 7 mm

3. Flow control Valve:

Technical Data

Port size : 0.635 x 10 ֿ² m

Pressure : 0-8 x 10 ⁵ N/m²

Media : Air

Quantity : 1

4. Connectors:

Technical data

Max working pressure : 10 x 10 ⁵ N/m²

Temperature : 0-100 º C

Fluid media : Air

Material : Brass

5. Hoses:

Technical date

Max pressure : 10 x 10 ⁵ N/m²

Outer diameter : 6 mm = 6 x 10 ˉ ³m

Inner diameter : 3.5 mm = 3.5 x 10 ˉ ³m

CHAPTER-4

Working Principle

The following figure shows general layout for the machine.

Fig 4.1 (a): General layout

Initially the air-compressor is started and allowed the receiver tank air

pressure to reach up to 8 bar. The supply air is then passed to the manifold

through FRL unit to condition the air and eligible to industrial use.

From the manifold a separate supply for the machine is taken out and

given to ON-OFF switch, so as to operate the machine at will without

interrupting the running of compressor.

Then the pipe carries compressed air first to machine’s Direction Control

Valve. At position ‘A’ shows the non-actuated circuit diagrams. At this position

the piston is steady and locked. All ports are in closed condition.

Fig 4.1 (b): Machine at Position ‘A’

At position ‘B’, the DC valve is at left hand position as shown in figure.

The cap end port & pressure port get connected to each other and the rod end

port gets connected to the exhaust port. The compressed air comes in the cap

end of the cylinder and pushes the pistons outwards. The air already present in

the rod end side is pushed out of the cylinder.

When the piston moves outwards, the force is transmitted through the

connecting link and the upper blade moves downwards. Before the actuating

DC valve the sheet is inserted in between the upper & lower blades. As upper

blade moves downwards, the stress is generated in the sheet metal and goes

beyond ultimate shear stress of sheet metal. And thus the shearing action

takes place.

Now the DC valve is operated to come at position ‘C’, as shown in figure.

The rod end port & pressure port get connected to each other and the cap end

port gets connected to the exhaust port. The compressed air comes in the rod

end of the cylinder and pushes the pistons inwards. The air already present in

the cap end side is pushed out of the cylinder.

The sheet metal is either again inserted for further cutting in case of

large pieces; the small cut pieces are removed and the next sheet is inserted to

cut.

Fig 4.1 (c): Machine Position ‘B’

Fig 4.1 (d): Machine Position ‘C’

CHAPTER-5

Proposed Work

To prepare any machine part, the type of material should be properly

selected, considering design, safety and following points:- The selection of

material for engineering application is given by the following factors:-

1. Availability of materials.

2. Suitability of the material for the required components.

3. Suitability of the material for the desired working conditions.

4. Cost of the materials.

In addition to the above factors the other properties to be considered while

selecting the material are as follows:-

1. Availability of materials.

2. Suitability of the material for the required components.

3. Suitability of the material for the desired working conditions.

4. Cost of the materials.

In addition to the above factors the other properties to be considered while

selecting the material are as follows:- Physical properties:-

These properties are colour, shape, density, thermal conductivity, electrical

conductivity, melting point etc. Mechanical properties:-

The properties are associated with the ability of the material to resist the

mechanical forces and load. The various properties are:-

i. Strength:

It is the property of material due to which it can resist the external

forces without breaking or yielding.

ii. Stiffness:

It is the ability of material to withstand the deformation under

stress.

iii. Ductility:

It is the property of material due to which it can be drawn into

wires under a tensile load.

iv. Malleability:

It is the property of material which enables it to be rolled into

sheets.

v. Brittleness:

It is the property of material due to which it breaks into pieces with

little deformation.

vi. Hardness:

It is the property of material to resist wear, deformation and the

ability to cut another material.

vii. Creep:

It is the slow and permanent deformation induced in a part

subjected to a constant stress at high temperature. We have selected the

material considering the above factors and also as per the availability of

the material.

Mild Steel:

Why steel, in particular?

Simply because, in my humble opinion, it is the greatest material

mankind has for construction. It is cheap, strong, readily available, easily cut,

joined, and formed. Wood can be light and stiff, but not very strong. The best

aluminum is strong and light, but very difficult to join. Titanium is superb in

terms of strength to weight ratio and stiffness but its incredibly expensive,

difficult to obtain, and even more difficult and expensive to machine properly.

There was no way your ever going to perform a battery-weld field-fix on a part

made from 7075-T6 aluminum or titanium! In the end we come back to steel

from mild carbon to some of the more exotic alloy steels pound for pound it is

the most righteous material available for our needs.

Where does steel come from? Steel is not a naturally occurring substance

- it is entirely man made. Steel is chiefly a combination of two naturally

occurring elements: iron and carbon (along with small amounts of other

elements - depending on the steel in question). The process by which man

makes steel, would, again, fill several volumes. Here is my amateur synopsis:

Iron is mined from the ground in the form if a reddish-brown rock called iron-

ore. This ore is then smashed up, strained, filtered, chemically treated etc,

until ultimately it is melted in huge blast furnaces into something called pig

iron. The process uses coke (a type of coal), which in turn imparts large

amounts of carbon to the pig iron. As a result, pig iron itself is full of

impurities, brittle, and unmachinable - practically useless. Except - it is the

raw material from which all other irons and steels are made.

Pig iron is so produced in either huge vats of molten material, or it is cast

into ingots (in fact, pig iron got its name because the ingots or “chunks”

produced were thought to have resembled piglets). Pig iron is then refined into

either metallic iron or steel using specialized furnaces and processes. The

distinction between the two is that metallic iron has between 2-6 A final words

about carbon. Carbon is critically important to our whole discussion because it

is the presence of carbon that turns the element of iron that is naturally soft

and weak, into the strong, rigid materials we know as iron and steel. Precisely

how this is so is beyond the scope of this article, suffice to say:

The strength, hardness and toughness that make the ferrous based

metals useful to us are profoundly influenced by the remarkable sensitivity of

the physical and chemical properties of iron crystals to relatively small

percentages of carbon dissolved within their matrixes (actually, the sensitivity

is to the movement of dislocations within the crystal space lattice). This

sensitivity to dissolved carbon is in fact, the very basis of ferrous metallurgy.

5.1 Machine Construction

The machine is basically made up of mild steel.

Reasons:

1. Mild steel is readily available in market.

2. It is economical to use.

3. It is available in standard sizes.

4. It has good mechanical properties i.e. it is easily machinable.

5. It has moderate factor of safety, because factor of safety results in

unnecessary wastage of material and heavy selection. Low factor of

safety results in unnecessary risk of failure.

6. It has high tensile strength.

7. Low co-efficient of thermal expansion.

Properties of Mild Steel:

M.S. has carbon content from 0.15

Bright Material:

It is a machine drawned. The main basic difference between mild steel

and bright metal is that mild steel plates and bars are forged in the forging

machine by means is not forged. But the materials are drawn from the dies in

the plastic state. Therefore the material has good surface finish than mild steel

and has no carbon deposits on its surface for extrusion and formation of

engineering materials thus giving them a good surface finish and though

retaining their metallic properties A poor, but perhaps useful metaphor may be

the use of fibre-mat and resin in fibre glass work. The bulk raw material of

fiberglass is the fiber matting (as iron is to steel) - but by itself the matting is of

no practical use. Not until we add the resin to it to make fibre glass (as we add

carbon to iron to make steel) do we get a useful product. In both cases, neither

raw material is much use alone, but combines them nor do we really have

something. Similarly, though carbon may only be present in small quantities,

just as the amount of hardener added to fibre glass resin has a profound effect

on the material, so does the small amount of carbon present in useful metallic

iron and steel.

Composition: Carbon 0.20

Properties: Tensile strength 44.54 kgf/mm

Yield stress 28 kgf/mm

Hardness 170 BHN

Uses: General purpose steels for low stressed components.

Table 5.1: Heat Treatment Chart

CHAPTER-6

Project Design and Drawings

6.1 Requirement Analysis

General Consideration in Machine Development

First Stage Design Consideration in New Machine

The word design means different things to different people a wallpaper

pattern a fashionable dress, the appearance of a racing car and so on. We

therefore start by defining what we mean by design in the present context ie.,

What design is all about. This understanding will lead to an examination of

1. Why we need to design particularly in an engineering environment, and

2. How we might best go about designing

What is design?

The Concise Oxford Dictionary explains design as a mental plan a

scheme of attack, end in view, adaptation of means to ends preliminary sketch

for picture invention Evidently there is a lot more to design than mere visual

aspects, and design is not restricted to engineering. Key components of this

explanation are as follows

1. Means to ends implies that we design not for the abstract mental

exercise, but with a definite goal in view some action or some physical

object will result from the design.

2. Mental suggests that design is a thinking process. When we design we

deal primarily with ideas, with abstractions rather than with numbers

and computers for example cannot do the job for us, though they can

help in certain tasks. No matter what we design, it is vital that we

develop and apply our imagination to visualize realistically the future

form of the artifact or action, how it will eventually come into being and

most importantly how it will thereafter interact with people and other

artifacts or actions.

3. Plan, scheme infers that design is distinct from implementation.

Designers especially in engineering seldom execute their plans, but

rather communicate them to others either by word of mouth, or visually.

So, can we now define design completely? No! And neither do we need to. A

rigid definition implies a rigid process, and design is anything but that. We

shall adopt the following interpretation as it incorporates the above concepts

and conveys a reasonably clear idea of what design is all about Design is the

application of creativity to planning the optimum solution of a given problem

and the communication of that plan to others. Apart from the communication

aspect therefore, we understand the essence of design to be problem solving,

though the type of problem encountered in design is not like a typical textbook

mathematics problem for example in which the unique correct solution is

guaranteed by following, automaton-like, a series of learned solution steps. A

design problem on the other hand is a real-life problem with many solutions,

some of which meet the problem requirements better, some worse, and where

the process of discovering the solutions is not mechanistic. Some problems

might appear not to need design as a solution can be cobbled together without

much thought. This is true enough if the solution can be based on direct

experience. However we shall soon come to realize that without experience

such a thoughtless solution usually comes to grief sooner or later the more

involved the problem and the more folk affected by the solution the more likely

is the solution going to fall in a heap. Any old solution will not do we must

strive for the optimum solution.

We expect that the design process, if properly carried out, will show a

high probability of disclosing a solution which is optimum or close-to-optimum,

if indeed a unique optimum exists.

The prime aim of this chapter is to develop a structured approach to

design an approach which will promote confidence in effectively solving real life

problems. We shall focus on problems involving engineering hardware

particularly for Design and Build Competitions however the approach is

perfectly general and applicable to problems arising from a marketing sortie or

a labour wrangle for example. The approach is thus very relevant to managers

and the like not just to ’hardware designers.

Why do we design?

Most people these days exist by providing things to others in the case of

engineers these things are technical muscle-power or knowhow, or physical

artifacts that is solutions to buyers or hirer’s particular problems. If these

clients are not completely satisfied with the thing provided then they will

dismiss the provider, go somewhere else for their next thing and tell everyone

about the provider’s unsatisfactory things. If this happens often enough to a

particular provider then that provider will cease to exist as a market force

nobody will want to know.

So clearly, if things are not designed with care and attention to clients

needs then the provider will have problems.

6.2. STATEMENT FOR DESIGN:

The Pneumatic Shearing machine is to be designed to operate at the

maximum pressure of 10 bar and the lever operating force required is 150N;

with the operating temperature of 2000 C. Cylinder Sizing Calculator. The air

cylinder sizing calculator below performs the following steps:

1. Calculate the area of the cylinder piston

Area = Pi x r2

2. Multiply the piston area by the air pressure to be used

Area x Pressure = Force Output

Note: The force output on the rod end of a cylinder will be slightly less due to

the displacement of the rod. The real force output of a cylinder will be less than

the theoretical output because of internal friction and external side loading. It

is best to use a cylinder that will generate from 25.

Material: Al. fs = 210kg/cm2

Bolt material: M.S. ft = 280 kg/cm2

Design a cylinder of internal diameter for Di=8 cm, Internal air pressure

P = 25 kg/cm

Max. ft =210kg/cm and

Max. ftb = 280 kg/cm.

Fig 6.2 (a): Cylinder

For safety purpose we will design the cylinder using factor of safety as 4

Therefore t = 4x 0.2

= 0.8 cm

To find the outer diameter of the cylinder,

Outer diameter Do = Di + 2 (t)

= 100mm

Width of packing = 0.5 cm

In side diameter of cylinder, D = D + (2 x width of packing)

= 8 + (2 x 0.5)

= 8 + 1 = 9 cm

Force trying to separate the flanges,

F = 3.14 D1 x P/4

= (3.14/4) (9) (9) x 25

= 1589.6 kg

Force trying to be resisted by four bolts, i.e. Force on each bolt F = F1

Let dc = core diameter

F = / 4 dc ft 1/2 dc

= (4 x 397.65/ 3.14 x 280)

= 1.344 cm

= 0.013 mm

Nominal diameters of the bolts are arranged at the corners of a square of such

size that the corner of the nut clears the outside of the cylinder. Therefore the

minimum Length of diagonal of square,

Fig 6.2 (b): Square

L = D + 2 t + 2 d

= 8 + 2 x (0.8) + 2 x 2

= 13.6 cm

The sides of the square L1 = L / 2

= 9.28 cm

The sides of the flange must be of sufficient length to accommodate the nuts

and bolts Heads without overhung.

Therefore Length

L2 = L1 + 2 d

= 9.28 + (4) L2

= 13.28 cm

In order to find the thickness of the flange, consider the bending moment. It

will take place due to the force in two bolts. Bending moment due to the force

in two bolts,

M1 = 2 F x L1/2

= 2 x 397.65 x 9.28 / 2

= 3690 kg – cm

The air pressure acting on half flange,

2 x F = 2 x 397.65 = 795.3 kg

Theflangesarescrewedwiththecylinderhavingmetricthreadsof4.4threads/cm

Pitch= (0.0228)

Hence the Nominal or Major diameter of thread,

= D + 2 x t

= 8 + 2 (0.8)

= 9.6 mm

Nominal radius of thread = Major diameter

= 9.6

= 4.8 mm

Now the depth of the thread, = 0.64 x pitch

= .64 x .228

= 0.145 cm

= 1.4mm

Core or minor radius of the thread, = Nominal radius depth

= 5.6-0.145

= 5.45 cm.

Mean radius of arc over which load due to air pressure may be taken to be

concentrated = (Nominal radius + minor radius)

= (5.6 + 2.8) = 4.2 cm.

The centroid of this arc, = 0.6366 x Mean radius

= 0.6366 x 4.2

= 2.67 cm

Bending moment due to air pressure,

M2 = 2 x F X The centroid of t

= 22 x 122.65 x 2.67

= 655.86 kg- cm.

Since M1 and M2 are in the opposite direction

Therefore the resultant bending moment will be,

M = M2 M1

= 655.86

637.78 = 18.08 kg cm.

6.3. PNEUMATIC CYLINDER

6.3.1. Design of Piston Rod:

Load due to air Pressure.

Diameter of the Piston (d) = 40 mm

Pressure acting (p) = 6 kgf/cm²

Material used for rod = C 45

Yield stress (σy) = 36 kgf/mm²

Assuming factor of safety = 2

Force acting on the rod (P) = Pressure x Area

= p x (Πd² / 4)

= 6 x {(Π x 4²) / 4}

P = 73.36 Kgf

Design Stress (σy) = σy / F0 S

= 36 / 2

= 18 Kgf/mm²

= P / (Π d² / 4)

∴ d = √ 4 p / Π [ σy ]

= √ 4 x 75.36 / {Π x 18}

= √ 5.33

= 2.3 mm

∴ Minimum diameter

of rod required for the load = 2.3 mm

We assume diameter of the rod = 15 mm

6.3.2. Design of Cylinder Thickness:

Material used = Cast iron

Assuming internal diameter

of the cylinder = 40 mm

Ultimate tensile stress = 250 N/mm²

= 2500 gf/mm²

Working Stress = Ultimate tensile stress /

factor of safety

Assuming factor of safety = 4

Working stress ( ft ) = 2500 / 4

= 625 Kgf/cm²

According to ‘LAMES EQUATION’

Minimum thickness of cylinder (t) = ri {√ (ft + p) / (ft – p ) -1 }

Where,

ri = inner radius of cylinder in cm.

ft = Working stress (Kgf/cm²)

p = Working pressure in Kgf/cm²

∴ Substituting values we get,

t = 2.0 {√ (625 + 6) / (625 – 6) -1}

t = 0.019 cm

= 0.19 mm

We assume thickness of cylinder = 2.5 mm

Inner diameter of barrel = 40 mm

Outer diameter of barrel = 40 + 2t

= 40 + (2 x 2.5)

= 45 mm

6.3.3 Diameter of Piston Rod:

Force of piston Rod (P) = Pressure x area

= p x Π/4 (d²)

= 6 x (Π / 4) x (4)²

= 73.36 Kgf

Also, force on piston rod (P) = (Π/4) (dp)² x ft

P = (Π/4) x (dp)² x 625

= (Π/4) x (dp)² x 625

∴ dp² = 73.36 x (4/Π) x (1/625)

= 0.15

dp = 0.38 cm

= 3.8 mm

By standardizing

dp = 15 mm

6.3.4 Length of piston rod:

Approach stroke = 160 mm

Length of threads = 2 x 20

= 40 mm

Extra length due to front cover = 12 mm

Extra length of accommodate head = 20 mm

Total length of the piston rod = 160 + 40 + 12 + 20

= 232 mm

By standardizing, length

of the piston rod = 230 mm

CHAPTER-7

Test Cases, Project Time Line & Task Distribution

7.1 Test Cases

7.1.1 Objectives

1) The improvements of processes and procedures.

2) The improvements of factory, shop and work place. Layout and design of

plat and equipment.

3) Economy in human effort.

4) Improvements in the use of materials, machines and manpower.

5) The development of better physical working environment.

Recording Techniques:

The next step in basic procedure after selecting the work to be studies is

to record all the facts relating to existing methods.

Purpose of Recording:

1) To enable the process to be clearly understood.

2) To present the existing facts for analogs.

Flow Process Charts:

Flow process chart is defined as a graphic representation of all storages,

occurring during a process or procedure which includes information considered

necessary for analysis such as time required quantity and distance moved etc.

Types of Flow Process Chart:

a) Man type: It records what the worker does.

b) Material type: It records what happens to the materials.

I. Equipment type: It records how the equipment is used. Flow process

chart gives a complete picture at what is being done and helps the man

to understand the facts and their relationship to one another.

Objective of Flow Process Chart:

1) To visualize the complete sequence of events occurring in process.

2) To study the events in a systematic way for the complete analysis of the

manufacture of the component part for the following purposes.

(a) To improve the layout.

(b) To improve material handling.

(c) To reduce delays.

(d) To diminutive, combine or re-arrange the events in a systematic way.

3) To submit the proposals to managements in a form this can be easily

understood.

4) To guide supervisors and operators regarding detailed operating

instructions.

According to the nature of job being studies and purpose for the record is

required.

(A) CHARTS : Outline process chart

Flow process chart: Man type

Flow process chart: Material type

Flow process chart: Equipment type

(B) CHARTS: Using time scale

a) Multiple activity charts

b) Simo charts

c) P.M.T.S. charts

(C) DIAGRAMS INDICATING MOVEMENTS and MODELS:

a) Flow diagrams

b) String diagrams

c) Cycle graph

d) Chromo cycle graph

e) Travel chart

5) To compare between two or more alternative methods.

6) To select operations for a detailed study.

7.2 Task Distribution

Method Study:

Method of the study is the systematic recording and critical Examination

of existing and proposed ways of doing work, as a means of developing and

applying.

Table 7.2 (a): More effective methods and reducing costs

Table 7.2 (b): Symbols, Activity and Results

7.3 Project Time Line

Manufacturing Process:

The process of conversion of raw material in to finished products using

the three resources as Man, machine and finished sub-components.

Manufacturing is the term by which we transform resource inputs to create

Useful goods and services as outputs. Manufacturing can also be said as an

intentional act of producing something useful. The transformation process is

shown below

Input

Conventional process

Output

Table 7.3: Description of Activity

Hence referring to the values we will plan the various processes using the

following machines:-

i. Universal lathe

ii. Milling machine

iii. Grinding machine

iv. Power saw

v. Drill machine

vi. Electric arc welding machine

CHAPTER-8

Advantages, Disadvantages and Applications

Advantages:

Pneumatic is more efficient in the technical field

Quick response is achieved

Simple in construction

Easy to maintain and repair

Cost of the unit is less when compared to other machine

No fire hazard problem due to over loading

Comparatively the operation cost is less

The operation of cutting is faster because the medium used to

operate is air

Continuous operation is possible without stopping

Disadvantages:

While working, the compressed air produces noise therefore a

silencer may be used.

High torque can not be obtained

Load carrying capacity of this unit is not very high.(<50 N)

Applications:

This machine is very useful for small scale industries

This machine is used to cut the roller sheet metal

All Industrial Application

CHAPTER-9

Cost Estimation

9.1 Introduction:

Cost estimation may be defined as the process of forecasting

the expenses that must be incurred to manufacture a product. These

expenses take into a consideration all expenditure involved in a design

and manufacturing with all related services facilities such as pattern

making, tool, making as well as a portion of the general administrative

and selling costs.

9.2 Purpose Of Cost Estimating:

1. To determine the selling price of a product for a quotation or

contract so as to ensure a reasonable profit to the company.

2. Check the quotation supplied by vendors.

3. Determine the most economical process or material to

manufacture the product.

4. To determine standards of production performance that may be

used to control the cost.

Types of Cost Estimation:

1) Material cost

2) Machining cost

Material Cost Estimation:

Material cost estimation gives the total amount required to collect the

raw material which has to be processed or fabricated to desired size and

functioning of the components.

These materials are divided into two categories.

1. Material for fabrication:

In this the material in obtained in raw condition and is manufactured or

processed to finished size for proper functioning of the component.

2. Standard purchased parts:

This includes the parts which was readily available in the market like

allen screws etc. A list in forchard by the estimation stating the quality, size

and standard parts, the weight of raw material and cost per kg. For the

fabricated parts.

Machining Cost Estimation:

This cost estimation is an attempt to forecast the total expenses that may

include manufacturing apart from material cost. Cost estimation of

manufactured parts can be considered as judgment on and after careful

consideration which includes lab our, material and factory services required to

produce the required.

1. MATERIAL COST:

Sr.

No. Part Name Material Quantity

Material

Cost

Machining

Cost

Total

Cost

A) Base Frame

1] Main Frame Mild Steel

20 Feet 600 500 1100

2] Angle

Section

Mild

Steel 1 50 50 100

3] Cylinder

Base Plate

Mild

Steel 1 30 30 60

4] Support

Links Mild Steel

2 30 30 60

B) Pneumatic Circuit Components

5]

Double

Acting

Cylinder

Plain

Carbon

Steel

1

4000

-

4000

6] Flow Control

Valve

Cast

Steel 2 850 - 850

7] Pipe PVC 3 m 120 - 120

8] Direction

Control Valve

Alloy

Steel 1 700 - 700

9] Pipe Fitting

Connections

Cast

Steel 3 150 - 150

C) Blades & Accessories

10] Shearing

Blades 35C8 2 300 400 700

11] Blade Link Mild Steel

1 20 30 50

12] Connecting

Link

Mild

Steel 1 30 30 60

13] Fork End Mild Steel

1 50 50 100

D) Others

14] Bolts Alloy Steel

11 80 - 80

15] Nuts Alloy Steel

3 10 - 10

16] Antirust Coat - 100 mL 20 - 20

17] Paint - 100 mL 40 - 40

Grand Total Cost (in Rupees) 7080 1120 8200

Table 9.2: Material cost

CHAPTER-10

Conclusion and Future Scope

Conclusion:

This project work has provided us an excellent opportunity and

experience, to use our limited knowledge. We gained a lot of practical

knowledge regarding, planning, designing drawing, purchasing,

computing and machining while doing this project work. We feel that the

project work is a good solution to bridge the gates between institution

industries.

We are proud that we have completed the work with the limited

time successfully. The machine is working with satisfactory conditions.

We are able to understand the difficulties in maintaining the tolerances

and also quality. We have done to our ability and skill making maximum

use of available facilities.

In conclusion remarks of our project work, let us add a few more

lines about our impression project work.

The chief advantage of our system is that, it cutting speed is varied.

The fast operation is done by the timer unit. This project is a low cost

automation project.

Further Scope of Work:

Since old age man is always trying to gain more and more luxurious.

Man is always trying to develop more and more modified technique with

increasing the aesthetic look and economic consideration. Hence there is

always more and more scope. But being the degree Engineers and having the

ability to think and plan. But due to some time constraints, and also due to

lack of funds, we only have thought and put in the report the following future

modifications:-

1) It can be made to run has bottle cap sealing machine. The stationary

platform can be made auto swiveling type by installing the timer and

heat sensor arrangement on the platform. It can be done such that when

the bottle mouth is sealed up to the desired temperature the electrical

heater circuit gets cut off. At the same time the motor installed on the

reduction gear box starts operating the bevel gearing and the platform

starts rotating thus it can be made auto rotating type.

2) It can be made hydraulic operated type by replacing the hand lever by

hydraulic cylinder and along with the ratchet and Paul arrangement.

3) It can be made hydraulically power operated by installing the gear oil

pump at the place of air compressor and pneumatic cylinder

arrangement.

4) It can be made rack and pinion operated or spring and lever operated, by

replacing the pneumatic circuit by rack and the pinion arrangement by

the square threaded screw and nut arrangement.

References:

1) J. P. Den Hartog, Advanced Strength of Materials (McGraw-Hill, New

York, 1952), TA 405 D4,1952. ; Author Name, Conference Name, year

etc.

2) E. W. Comings, High Pressure Technology (McGraw-Hill, New York,

1956). ; Author Name, Conference Name, year etc.

3) Adaptive Steady State Genetic Algorithm for scheduling university

exams”,AlSharafat W.S.; Al-Sharafat M.S., Networking and Information

Technology (ICNIT), 2010 International Conference on , vol., no., pp.70-

74, 11-12 June 2010 doi: 10.1109/ICNIT.2010.5508555

4) http://google.com

http://www.engineersedge.com/

http://www.efunda.com/

http://www.steeltubeinstitute.org/

http://www.emjmetals.com/

http://www.usstubular.com/

1. Machine design R.S. Khurmi

2. Work shop technology R.K.Jain.

3. Machine tool design handbook.

4. P.S.G. Design Data Book

5. www.altavista.com

Photography:

http://google.com/

http://www.engineersedge.com/

http://www.efunda.com/

http://www.steeltubeinstitute.org/

http://www.emjmetals.com/

http://www.usstubular.com/

http://www.altavista.com/

pneumatic sheet cutting machine

Education