Rahul Soni's Training Report

7/27/2019 Rahul Soni's Training Report

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1

A

REPORT ON

PRACTICAL TRAINING

TAKEN AT

National Engineering Industries Ltd. (NEI),

JAIPUR, RAJASTHAN.

FROM: 01.06.2012 to 30.06.2012

IN THE PARTIAL FULFILLMENT FOR AWARD THE DEGREE OF

Bachelor of Technology

From

Rajasthan Technical University

Session 2012-2013

Submitted To: Submitted by:

Rajesh Ranjan Sir , Rahul SoniHead of Department Mechanical Engineering,

IIMET JAIPUR B.TECHIVYEAR,

. VII SEM IIMET.

Department of Mechanical Engineering

International Institute of Management, Engg. & Tech.

Sitapura Industrial Area, Tonk Road, Jaipur



2

ACKNOWLEDGEMENT

It is a matter of great pleasure for me to express my profound feelings of

reference to my worthy advisor MR. LALIT MOHAN SHARMA [ NATIONAL

ENGINEERING INDUSTRIES LIMITED, JAIPUR ( project head )]. As his inspiring

guidance and everlasting enthusiasm have been valuable assets during the

tenure of my training.

The beatitude, bliss, and euphoria that accompany the successful

completion of any task would not be complete without the expression of

appreciation of simple virtues to the people who made it possible. So, with

reverence, veneration honor I acknowledge all those guidance and

encouragement has made successful in winding up this.

It gives me immense pleasure in acknowledge the help I have received

while making this report on “ NATIONAL ENGINEERING INDUSTRIES LIMITED,

JAIPUR ”. I owe my profound gratitude By Mr.V.K.Agrawal (H.O.D., ME) for his

kind patronage and generosity. A great deal of thanks to Ms. Kail ash Meena

(Seminar Coordinator), Ms.Monisha Jain (T.P.O.) and entire faculty member for

imparting knowledge success of the project.

A seminar of this type naturally gained number ideas of the field of

Mechanical Engineering. We would also like to express our heartfelt

appreciation to all other people who help us.


Rajesh Ranjan Sir , Rahul Soni ,

Head of Department Mechanical Engineering,

IIMET JAIPUR B.TECH IVYEAR,. VII SEM IIMET.



3

ABSTRACT

This paper presents details of a computer interface developed for vibration

monitoring and diagnostics of tapered roller bearings, based on experiments

conducted for bearing fault diagnosis. An experimental set up was designed and

fabricated for testing various tapered roller bearings to obtain their vibration

characteristics – three defect-free and nine defective tapered roller bearings were

tested. The defective bearings tested were: bearings with outer race defects,

roller defects and combination of both. The bearing vibration data were acquired

using NI DAQ and Lab View Virtual Instrumentation Software, which were

further processed using computer interface developed for diagnostics. The

computer interface used various time and frequency domain parameters like:

peak to valley, RMS value, kurtosis, skew-ness, envelope analysis, etc. to

diagnose faults in bearings. The interface was able to diagnose point defects in

the tapered roller bearings. The above computer interface, with some

modifications can as well be used for diagnosing defects in plain roller bearings

also.

Submitted To: Submitted by:Rajesh Ranjan Sir , Rahul Soni ,


IIMET JAIPUR B.TECH IVYEAR,

. VII SEM IIMET.



4

PREFACE

As a part of curriculum prescribed by the Rajasthan Technical University for

the degree of B. Tech of engineering a total of 30 days practical training is

required by the student of engineering, 34 days taken by me at:

“NATIONAL ENGINEERING INDUSTRIES LIMITED, JAIPUR (RAJ.)”

From: 01 JUNE 2012 to 30 June 2012 .

The tanning report infects a summary of what my Practical Training under

Large Dia. Bearing (LDB) Division.

This report prepared during the practical training which is student‟s first and

greatest treasure as it is full of experience, observation and knowledge.

The summer training was very interesting and gainful as it is close to real what

have been studied is all the years through was seen implemented in a modified

and practical form.

The student wishes that this Gorgeous Private Sector undertaking success so that

it may flourish and serve the nation which has reached significant years of its

independence and has to achieve many goals.

“NATIONAL ENGINEERING INDUSTRIES LIMITED, JAIPUR ”


Rajesh Ranjan Sir , Rahul Soni ,


IIMET JAIPUR B.TECH IVYEAR,. VII SEM IIMET.



5

INDEX

1. INTRODUCTION [i]

2. CERTIFICATE [ii]

3. ACKNOWLEDGEMENT [iii]

4. ABSTRACT [iv]

5. PREFACE [v]

6. DEFINITION OF INDUSTRY [1]

7. INTRODUCTION OF NEI [2]

8.

INTRODUCTION OF BEARING [3-5]9. INTRODUCTION OF LDB DIVISION [6]

10. MANUFACTURING PROCESS OF ROLLER FOR LARGE SIZE

BEARING

a. Black Roller (From HT) [7]

b. OD Grinding (Centre less) [8-9]

c. Hardening(From HT) [10]

d. OD Grinding (Centre less) [10]

e. Head (Honing) [11-13]

f. OD Grinding (Finish) [14-15]

11. STUDY ABOUT PNUEMATIC MACHINE[16-25]

12. TROUBLE SHOOTING [26-27]

13. CONCLUSION [28]

14. BIBLIOGRAPHY [29]

15. REFERENCE [30]



6

Industrial linkage

„„When one Industry depends on the output of another‛‟

This can cause problems if one industry has production problems or closes down

The CAR INDUSTRY is a good example – each component (engine parts, lights, body etc.)

may be produced by a different company before it goes to the ASSEMBLY PLANT.

Bearing Industry Global Scenario:-

The world Market of quality Bearing is very vast. The Big players of bearing sector are

present in U.S.A, Russia, Japan, China and Eastern Europe. Some of leading bearingManufacturers are: -

- NSK Japan

- NTN Japan

- KOYA Seiko Japan

- FAG Germany

- SKF Sweden

- NRB France

- Timken USA

There are few of leading bearing manufacturer present in India. Most of the big player is

having either technical or financial Collaboration with leading Auto-Manufacturer

International Collaboration gives Access to best technology in the world.

BEARING INDUSTRY INDIAN SCENERIO:-

The Indian Bearing Industry is estimated at Rs. 30 Billion Approximately. The Industry has

established a highly diversified product range of around 1000 type of Bearing having High

Volume Demand. As much as 70% of the total

Demand for common varieties and size of bearing is met by the domestic Industry, and the

remaining demand to the tune of 30% is imported essentially for Industrial Application and

special purpose.

The Indian bearing Industry can be divided in to the organized sector and un-organized

sector. The organized sector primarily caters to the original equipment Manufacturer (OEM)

Segment, which predominantly comprises automotive industries and other mechanicalIndustrial users. The replacement market is dominated by unorganized Sector.



7

ABOUT NEI

Bearing in India started with the setting up of manufacturing unit in JAIPUR

by the Birla Group in 1946 under the name of "National Bearing Company

Ltd."

The 1st Bearing was manufactured in 1950 with a modest start of 30 thousand

bearing in 19 Sizes. The Bearing Races (Soft) was Manufactured by the Tiny

Unit in the Small Scale Sector at Jaipur during 1970 on Job Work basis.

It is a view to utilize the end piece of the Stainless steel tube which could not be fed to the Multi operation of National Engineering Industries Jaipur.

There after there is a continuous growth of this Industry and now it has grown

to a level that Almost All the Leading Manufacturer of the country are

procuring Soft Bearing Races from JAIPUR. The National Engineering

Industries procure lakes of Ring every month from these Bearing Race

Manufacturing Unit.

The other leading manufacturer like S.K.F., FAG, TATA Bearing, NBC are

also procuring the Bearing races from Jaipur. In addition to above, the Small

Scale Units manufacturing bearing in the state of Rajasthan, Delhi, Gujarat

and Punjab also purchasing Bearing Races and components from Jaipur.



8

BEARING:-

A bearing is a device to allow constrained relative motion between two or more parts,

typically rotation or linear movement.

Bearings may be classified broadly according to the motions they allow and according to

their principle of operation as well as by the directions of applied loads they can handle.



9

TYPES:-

There are many different types of bearings.

Type Description FrictionStiffness

†

Speed Life Notes

Plain

bearing

Rubbing

surfaces,

usually with

lubricant; some

bearings use

pumped

lubrication and

behave

similarly to

fluid bearings.

Depends on

materials and

construction,

PTFE has

coefficient of

friction

~0.05-0.35,

depending

upon fillers

added

Good,

provided

wear is

low, but

some

slack is

normally

present

Low to

very

high

Low to very

high - depends

upon application

and lubrication

Widely used,

relatively

high friction,

suffers from

stiction in

some

applications.

Depending

upon the

application,

lifetime can

be higher or

lower than

rolling

element bearings.

Rolling

element

bearing

Ball or rollers

are used to

prevent or

minimizerubbing

Rolling

coefficient of

friction with

steel can be

~0.005

(adding

resistance

due to seals,

packed

grease, preload and

misalignmen

t can

increase

friction to as

much as

0.125)

Good,

but some

slack is

usually present

Moderat

e to high

(often

requirescooling)

Moderate to

high (depends

on lubrication,

often requiresmaintenance)

Used for

higher

moment

loads than

plain bearings with

lower friction

Jewel

bearing

Off-center

bearing rolls in

seating

LowLow due

to flexing

Low

Adequate

(requires

maintenance)

Mainly used

in low-load,

high precision

http://en.wikipedia.org/wiki/Stiffness

http://en.wikipedia.org/wiki/Plain_bearing



http://en.wikipedia.org/wiki/Stiction

http://en.wikipedia.org/wiki/Rolling_element_bearing




http://en.wikipedia.org/wiki/Jewel_bearing








http://en.wikipedia.org/wiki/Stiction



http://en.wikipedia.org/wiki/Stiffness



10

work such as

clocks. Jewel

bearings may

be very

small.

Fluid

bearing

Fluid is forced

between two

faces and held

in by edge seal

Zero friction

at zero

speed, low

Very

high

Very

high

(usually

limited

to a few

hundred

feet per

second

at/byseal)

Virtually infinite

in some

applications,

may wear at

startup/shutdow

n in some cases.

Often negligible

maintenance.

Can fail

quickly due

to grit or dust

or other

contaminants

.

Maintenance

free in

continuous

use. Can

handle verylarge loads

with low

friction.

Magneti

c

bearings

Faces of

bearing arekept separate

by magnets

(electromagnet

s or eddy

currents)

Zero friction

at zero

speed, but

constant

power for

levitation,

eddy

currents areoften

induced

when

movement

occurs, but

may be

negligible if

magnetic

field is

quasi-static

Low

No

practical

limit

Indefinite.Maintenance

free. (with

electromagnets)

Active

magnetic

bearings

(AMB) need

considerable power.

Electro

dynamic

bearings

(EDB) do not

require

external

power.

Flexure

bearing

Material flexes

to give and

constrain

movement

Very low LowVery

high.

Very high or

low depending

on materials and

strain in

application.

Usually

maintenance

free.

Limited

range of

movement,

no backlash,

extremely

smooth

motion

Stiffness is the amount that the gap varies when the load on the bearing changes, it is distinct

from the friction of the bearing.

http://en.wikipedia.org/wiki/Fluid_bearing



http://en.wikipedia.org/wiki/Magnetic_bearings




http://en.wikipedia.org/wiki/Electromagnet


http://en.wikipedia.org/wiki/Eddy_current



http://en.wikipedia.org/wiki/Electrodynamic_bearing



http://en.wikipedia.org/wiki/Flexure_bearing



http://en.wikipedia.org/wiki/Friction

http://en.wikipedia.org/wiki/Friction


















11

LARGE DIA. BEARING DEVISION

(High Chromium Steel)

Heading Machine

Flashing (Rough Grinding) (High Grind Oil + H2O)

Soft Grinding ( (High Grind Oil + H2O)

Heat Treatment

Work Hardening Tumbler

Hard Grinding (G2)

Finish Grinding (G3) (Kerosene)

Rough Lapping (L1)

Finish Lapping (L2)

Ultra Sonic Washing Machine (Kerosene)

Visual Inspection

Anti-Rust Oil Packaging Maxi Grind Oil + H2O and High Grind Oil +H2O (Coolant)



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BLACK ROLLER (Heat Treatment Process)

LDB’s Tapered Roller Bearing:-

Tapered roller bearings are designed in such a way that vertices of the cone for each roller and

those for the inner and outer raceways coincides on the bearing axis or extensions of the

raceways and rollers converge at a common point on the axis of rotation. This results in true

rolling motion of the rollers on the raceways at every point along the rollers.

The tapered roller bearings support radial loads and axial loads from one direction only. The

line contact between rollers and raceways provide the bearings with a high load carrying

capacity. Steep angle tapered roller bearing with exceptionally steep cone angle enables the

bearings to take heavier axial load.

The bearings are of separable type, enabling separate mounting of cups and cones. Since the

tapered roller bearings can absorb thrust loads in one direction only, these bearings should

generally be installed as opposed mountings. The correct amount of radial and axial clearance

is obtained by adjusting the two bearings against each other.

Besides, double row and four row tapered roller bearings are also widely used for heavy loads

such as rolling mills.

The inner and outer ring raceways are segments of cones and the rollers are also made with a

taper so that the conical surfaces of the raceways and the roller axes if projected, would all

meet at a common point on the main axis of the bearing.

http://en.wikipedia.org/wiki/Race_(bearing)

http://en.wikipedia.org/wiki/Cone_(geometry)




http://en.wikipedia.org/wiki/Race_(bearing)



13

OD GRINDING (CENTRELESS)

LDB’s Taper Roller Bearing:-

This conical geometry is used as it gives a larger contact patch, which permits greater loads to

be carried than with spherical (ball) bearings, while the geometry means that the tangential

speeds of the surfaces of each of the rollers are the same as their raceways along the whole

length of the contact patch and no differential scrubbing occurs. When a roller slides rather

than rolls, it can generate wear at the roller-to-race interface, i.e. the differences in surface

speeds creates a scrubbing action. Wear will degenerate the close tolerances normally held in

the bearing and can lead to other problems. Much closer to pure rolling can be achieved in a

tapered roller bearing and this avoids rapid wear.

The rollers are guided by a flange on the inner ring. This stops the rollers from sliding out at

high speed due to their momentum.

The larger the half angles of these cones the larger the axial force that the bearing can sustain.

Tapered roller bearings are separable and have the following components: outer ring, inner

ring, and roller assembly (containing the rollers and a cage). The non-separable inner ring and

roller assembly is called the cone, and the outer ring is called the cup. Internal clearance is

established during mounting by the axial position of the cone relative to the cup.

RAW MATERIAL:-

The Races & Rolling elements of Bearing are subjected to stress on a very small contact

surface must be of such material also as to with stand wear and have high elastic Limit &

fatigue Limit. The raw material being used by the Industry for Manufacturing of various

Bearing components are as under:

http://en.wikipedia.org/wiki/Contact_patch

http://en.wikipedia.org/wiki/Contact_patch



14

CUP AND CONE:-

The raw material used in the Manufacturing of bearing Races is SAE 52100 high Carbon

Chrome bearing steel, which has composition similar to EN-31 (100 CR 6 As per BIS

specification). The raw material for Bearing Races is in the form of Rods & Seamless HollowTubes.

This is a Spheroids Annealed Steel. Approx. 80% of the Seamless Hollow tubes are purchased

by the Industry from M/s. Indian Seamless Metal tube PUNE, while the rest of the tube used

in the cluster is imported material.

The Steel bars are purchased from M/s. Indian Seamless Steel & Alloy Pune & M/s. Mahindra

U gin Steel Company KHAPOLI (Maharashtra).

Some of the units are buying the steel scrap rod for manufacturing bearing races.

Bearing Races material and their heat treatment are required to be selected carefully, taking

account the mechanical strength and required life of the Bearing,

Approximate required composition for bearing races are Constitute % Composition

Carbon 0.95 to 1.1

Chromium 1.4 to 1.6

Manganese 0.50 max.

Silicon 0.15 to 0.35Sulphur 0.025 (Max.)

Phosphorous 0.05

CAGE'S:-

Cage is used to return balls at proper distance to prevent them from containing each other and

to prevent a temperature rise and resultant damage due to friction.

The Material for manufacturing cages is CRCA Strips ofC2015 Bearing grade steel having

carbon percentage at0.08% max and Magnesium ranging from 0.25% to 0.45%

MANUFACTURING PROCESS OF TAPER ROLLER BEARING

Forged rings (De-scaled) as raw material

(SAE 52100 steel)

↓

Turning Operation

↓

Centre Less Grinding

↓



15

Heat Treatment

↓

Hardness Testing

↓

Rough Grinding↓

Finish Grinding

↓

Honing & Super Finishing

↓

Washing

↓

Application for Rust Preventive

↓

Ready For Dispatch to Assembly

HARDENING (Heat Treatment Process)

Heat treatment process is the process of hardening the soft material. The row material is soft

material and it has to be hardened before grinding, and hardening increase the life of bearing.

Hardening is done in a special furnace named CHUGAIRO furnace.

The soft machined material is feed in the furnace and washed at 60 0 C, then send to a chamber

where the material heated in four chambers the first chamber has the temperature 840 0 C and

further chamber contains the 8500

C temperature.

Then it dipped into an oil tank at temperature 250C where the material get quenched then it

washed and then it tempered in water about 90 min. at temperature 1050 C . then dried and

cooled in air. The hardened material is obtained.

The systematic flowchart is shown in following fig:



16

Fig2: flowchart of heat treatment

After heat treatment following process are done:

HEAD (HONING)

DIFFERENT PROCESS FOR CONE:-

Dimensions Checking:-

Before starting the grinding process, various dimensions of cone should be checked in a

machine or manually. Various dimensions to be checked are:

Flange diameter

Cone width

Cone track diameter

Bore diameter

Face Grinding:-

Face is the surface at side of the inner and outer race , face should be finished indeed to get the

desire width of the bearing and since the bearing is a mating part and it has to be assembled



17

somewhere in the machine where it should be fit precisely. The face grinding is done in a

machine where the faces are grinded in between the grinding wheel.

Size Limit : UCL +35 µm

: LCL -35 µm

Width Variation : 5µm

There are various semi-automatic face grinding machine installed in taper section for cone

1. DAISHO MACHINE

2. NISSEI MACHINE

3. NISSEI MACHINE

OD (Outer Dia.) Grinding

OD is the circumferential surface of the outer race of the bearing. The OD should be surface

finished since the bearing has to be assembled in machine. It is obtain in an OD grinding

machine. In this machine the outer race is rotated between two grinding wheel.The outer race

is passed in machine three times to get highly finished as follows:

1. Rough1

2. Rough2

3. Fine finish

Size Limit : 15 to 35 µm

Target Size : +30 µm

Flange Grinding:-

The flange should be surface finished since the bearing has to be assembled in machine. It is

obtain in the flange grinding machine. In this machine one grinding stone is used to cut and

grind the flange portion of cone.

NC Mode - AUTO

Feed Mode - AUTO

Override - 120% (used to change machine speed.)

Tool movement during grinding is in all three dimensional axes i.e. X, Y, Z axis.



18

Bore Grinding:-

Bore is the inner circumferential surface of the bearing. The bore should be surface finished

since the bearing has to be assembled in machine. It is obtain in the bore grinding machine. In

this machine the grinding stone is moved in X and Y axis.

Size Limit : +4 µm to -4 µm.

TOOL movement during grinding is in only two dimensional axes i.e. X, Z axis.

Auto Dimension Check:-

Various dimensions of cone are checked in this machine. This machine includes various

sensors for sensing the dimension of cone. This machine use weight sensors and position

sensors to identify the position and weight of cone. All dimensions should be checked in this

machine.

M1 Φ0.7 ID1 - X

M2 Φ 2.1 ID 2 - X

M3 Φ -2 TAPER

M4 Φ -0.2 ID1 - Y

M5 Φ 1.6 ID 2 – Y

M6 Φ 0.9 OVALITY

It automatically discards the work piece if its dimensions are not compatible with pre-feed

data. The limitations of size are:

Size limit : +4µm to -4 µm.

TAPER : 5 µm maximum

OOR : 5 µm maximum

CHATTER : 3 µm maximum

SQUARENESS : 5 µm maximum

Honing Machine:-

Honing is an abrasive machining process that produces a precision surface on a metal work

piece by scrubbing an abrasive stone against it along a controlled path. Honing is primarily

used to improve the geometric form of a surface, but may also improve the surface texture.



19

DIFFERENT PROCESS FOR CUP:-

OD Grinding:-

OD is the circumferential surface of the outer race of the bearing. The OD should be surfacefinished since the bearing has to be assembled in machine. It is obtain in an OD grinding

machine. In this machine the outer race is rotated between two grinding wheel. The outer race

is passed in machine three times to get highly finished as follows:

Rough1, Rough2, Fine finish.

Size Limit : 15 to 35 µm

Target Size : +30 µm

Honing Machine:-

Honing is an abrasive machining process that produces a precision surface on a metal work

piece by scrubbing an abrasive stone against it along a controlled path. Honing is primarily

used to improve the geometric form of a surface, but may also improve the surface texture.



20

OD GRINDING (FINISH)

ASSEMBLY LINE:-

Once respective CUP and CONE of corresponding bearing is finished, they are sent in the

Assembly line where these cup and cone get assembled with retainers having rollers in themand after some important test, they are finally packed and are ready for use.

Laser Printing Machine:-

It is a machine which is used for marking purpose of the company brand and specification on

respective cup or cone. This technology utilizes laser beam for marking. The movement of

laser beam is controlled by automatic 3d table movement. The point on metal surfaces where

these laser beams hits leave marks as required. Names of few Laser Machine which are

installed in Taper Bearing Section are:

4. AKSHAR FIBER-PRO.

5. SAJIAJANAND Laser Technology ltd.

Roll Filling Machine:-

It is an automatic machine which is actuated by pneumatic technology. In this machine, first

Retainer is placed on first station where rollers are inserted at their respective position. Then

they are sensed by position sensor, actuated by pneumatic and then cone is fixed within cage.

Pressing Machine:-

It is an automatic machine which is actuated by pneumatic and hydraulic technology both. The

Cone is pressed against Retainer with down stroke powered by hydraulics and upstroke

powered by pneumatics.

Weight check:-

At this station, Weight of bearing is checked and if the weight is not compatible with the given

standard of weight limits, machine will reject the work piece sample.

Demagnetizer:-

It is a machine which is used to remove magnetism induced during the above process. It is

done by impact hitting.

Washing: -Then the bearing is washed by fast stream of kerosene jet.



21

Noise checking: -

The bearing is supposed to be produce low noise hence this machine rotates the bearing at

certain rpm and noise is checked. The noise limit is nearby 0.1 Mpa.

Press checking:-

At this station, the bearing is checked whether its assembly is pressed properly or not.

Final checking:-

This machine has 2 or 4 stations where various dimensions of final bearing are checked. If any

bearing is found incompatible with the given dimensions and tolerances, they are rejected by

the machine.

In ideal position 1, width of bearing, run out and comment or clearance of bearing is checked.

And at ideal position 2, bore size, taper and roundness are checked.

All those bearings which does not have compatible size and tolerance with the given data, they

are rejected by the machine itself.

Ideal position 1 : width, run out, comment

Ideal position 2 : bore size, bore taper, bore roundness

Oiling and Drawer Machine:-

In this machine, bearing is subjected to a fast flowing stream of coolant which is used to

lubricate the bearing parts. And then the excess oil is again sucked by the machine.

Visual Inspection:-

Now, the bearing is checked manually by the operators. All the dimensions and surface

properties are checked and rejected work piece are sent again for correction.

Packing:-

Finally, finished product is packed for market use and export.



22

THE PNUEMATICS TECHNOLOGY INVOLVED IN ROLL FILLING

AND PRESS WORKING MACHINE.

In today‟s challenging environment, technology departments are in danger of being crushed

between the pincers of growing business expectation and an unstinting focus on cost control

and development.

Introduction of pneumatics:-

A fluid power system is one that transmits and control energy through the use of pressurized

liquid and gases. In pneumatics, the power comes from the atmosphere and it is reduced by

compression, thus increasing its pressure. Compressed air is mainly used to do work by acting

on a piston or vane.

Basic application of pneumatics:-

6. Operation of system valves for air, water and chemicals.

7. Lifting and moving in slab molding machine.

8. Holding in jigs and fixtures in assembly machinery and tools.

Basic pneumatic system:-

Pneumatic cylinders, rotary actuators and air motors provide the force and movement of most

Pneumatics control system, to hold, move, and form and process material.

To operate and control these actuators, other Pneumatics components are required i.e. air

service unit to prepare the compressed air and valve to control the pressure, flow2 and

direction of movement of the actuators.

A basic Pneumatics system consists of 2 main sections:

9. The air production and distribution system

10. The air consuming system

11. Air production system

12. Compressor

13. Electric motor

14. Pressure switch

15. Check valve

16. Tank

17. Pressure gauge



23

18. Air dryer

19. Line filter

Air consuming system:-

20. Air take-off

21. Auto drain

22. DCV

23. Actuators

24. Speed controllers

Block diagram of roller filling and press machine:-

Major process carried out by pneumatics in roll filling and press machine:-

Main components of roll filling and press machine which are actuated by pneumatics:

25. Cage supply

26. Cage positioning

27. Roller filling in cage

28. Cage and roller assembly check

No cone

No roller Roller unit Cone supply

checkCage

positioningset press discharge

orientationtransfer

No

cage Cage supply

Cage

Assembly

Unit

Assembly

unit

No cone

No roller Roller unit Cone supply

checkCage

positioningset press discharge

orientationtransfer

No

cage Cage supply

Cage

Assembly

Unit

Assembly

unit



24

29. Cone supply

30. Pressing

31. Check and discharge

Direction control valve:-

A directional control valve determines the flow of air between its ports by opening, closing

and changing its internal connections. The valves are described in terms of the number of

ports and the number of switching position, its normal position, and the method of

operation.

The first two points are normally expressed in terms 5/2, 3/2, or 2/2etc



25



26

Mono-stable and bi-stable valve:-

Spring returned valve is mono-stable. They have a defined preferred position to which

they automatically return.

A bi-stable valve has no preferred position and remains in either position until one of its

two impulse signals are operated.



27

Valve types:-

Poppet valve:- flow through a poppet valve is controlled by a disc or plug lifting at right

angles to a seat, with an elastic seal.

Sliding valve:- spool, rotary and plane slide valves use a sliding action to open and close

ports.

Spool valves:- a cylindrical spool slides longitudinally in the valve body with the air flowing

at right angles to the spool movement. Spools have equal sealing areas and are pressure

balanced.

Elastomeric Seal:- common seal and seal arrangements are as shown in figure. O rings are

fitted in grooves on the spool and move in a metal sleeve. Two of them are crossing output

ports, which are divided into a great number of small holes in the sleeve.

Metal seal:-

Lapped and matched metal spool and sleeve valves have very low frictional resistance,

rapid cycling and exceptionally long working life.

Plane slide valve:-

Flow through the ports is controlled by the position of a slide made of metal, nylon or other

plastic.

Direction

Control Valve

Poppet

valve

Sliding

valve

Spool

valve

Rotary

valve

Plane Slide

valve

Elastomer seal

Metal

seal

Direction

Control Valve

Poppet

valve

Sliding

valve

Spool

valve

Rotary

valve

Plane Slide

valve

Elastomer seal

Metal

seal



28

Rotary valves:

A metal ported disk is manually rotated to inter connect the ports in the valve body .Pressure supply is

above the disc.

Basic Rules For Drawing Pneumatic Circuits & Symbols

Pneumatic circuits are represented by common symbols and should be drawn following several

basic guidelines. By following these guidelines engineers can quickly and simply construct

circuits that can be easily and safely interpreted by all those involved in system design,

specification, manufacturing and maintenance.

The symbols used for constructing fluid power systems and for defining individual components

are detailed in the standard ISO 1219, which covers both pneumatic and hydraulic devices.

This states that: „A symbol consists of the lines, letters and abbreviations which identify the

purpose and method of operation of the component represented. The symbols show connections,

flow paths and the functions of the components represented. The symbols do not indicate the

physical location of ports or the position of control elements on actual components. With certain

obvious exceptions symbols may be reversed and/or rotated without altering their meaning‟.

It should be noted, however, that the ISO standards do not always keep abreast of developments in pneumatics technology, so that new products often fail to be clearly defined until sometime after

their introduction. As a result, product manufacturers often use proprietary symbols until such

time as a standard unit is defined.

The situation can be further confused by the fact that the Japanese Industry Standard (JIS) and the

American Standards Authority (ASA) also use differing sets of symbols.

All three standards authorities use common symbols for air preparation equipment and, with a few

exceptions, valves; the JIS, however, reflecting the greater diversity of equipment originating in

Japan, often uses different symbols for special purpose or newly developed actuators.

For most pneumatic circuits, however, the standard ISO nomenclature is adequate, with the



29

majority of air preparation, air treatment, actuators, valves and ancillary components being

defined by common symbols.

A complete list of symbols and guidance on their construction is available.

When constructing a circuit diagram, there are always basic rules that should be followed.• The flow of working energy in a circuit diagram is drawn from the bottom to the top of the diagram

• The sequence of the working cycle is from left to right of the circuit diagram; the air supply is

therefore shown at the lower left, with the cylinder that performs the first stroke of the cycle

being situated in the upper left.

• Power valves are drawn directly below the cylinders they operate.

• All circuit components are shown in their rest position, with the supply under pressure.

• Electrical connections are not generally shown.

• Mechanically operated valves, controlling the rest position of cylinder driven parts, are operated in

the rest position and must be drawn accordingly; external connections are drawn to the valve

symbol square on the operator side.



30

Fig: ISO symbols for Air Treatment Equipment



31

Basic Pneumatic Circuits:-



32

TROUBLESHOOTING:-

Appearance Cause Action Photo

Small indentationsaround the

raceways and

rolling elements.

Dull, worn

surfaces.

Lack of cleanliness before

and during

mounting

operation.

Do not unpackbearing until just

before it is to be

mounted. Keep

workshop clean

and use clean

tools.

Outer ring of a sphericalroller bearing with

raceways that have been

worn by abrasive

particles. It is easy to

feel where the dividing

line goes between worn

and unworn sections.

Grease discolored

green.

Ineffective seals Check and

possibly improvethe sealing.

Lubricant

contaminated by

worn particles

from brass cage

Always use fresh,

clean lubricant.

Wipe the grease

nipples. Filter the

oil.


Worn, frequently

mirror-like, surfaces;

at a later stage blue

to brown

discoloration.

Lubrication has

gradually been

used up or has lost

its lubricating

properties.

Check that the

lubricant

reaches the

bearing.

More frequent

re lubrication.

Outer ring of a spherical

roller bearing that has

not been adequately

lubricated. The

raceways have a mirror

finish.

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33


Depressions in raceways.

These depressions are

rectangular in roller bearingsand circular in ball bearings.

The bottom of these

depressions may be bright or

dull and oxidized.

The bearing

has been

exposed tovibration while

stationary.

Secure the

bearing during

transport byradial

preloading.

Provide a

vibration-

damping base.

Where possible,

use ball

bearings

instead of roller

bearings.Employ oil bath

lubrication,

where possible.

Outer ring of taper

roller bearing

damaged byvibration during

operation.

Vibration damage to

the ring of a

cylindrical roller

bearing. The

damage has arisen

while the bearing

was not running.

Inner and outer ring

of a cylindrical roller

bearing exposed to

vibration. The inner

ring has changed

position.












34

CONCLUSION

My training at NATIONAL ENGINEERING INDUSTRIES, JAIPUR was veryfruitful and I gained a lot of practical knowledge about various manufacturing

processes and techniques. I also got the opportunity to realize the challenges

faced and expertise required in manufacturing processes for mass production.

It was indeed a great experience undergoing training at the plant.



35

BIBLIOGRAPHY

PLANT RECORD (Notes) : Files

A COURSE IN MECHANICAL POWER : R.K.Bansal

PROTECTION OF POWER SYSTEM : B. Ram

POWER TRANSFORMER : Tata Magr. Hill

ELECTRICAL ENGINEERING : Tata Magr. Hil

PRODUCTION ENGINEERING : P.C. Sharma

BEARING CONTENTS AND ENGINEERING: ArvindPalmgren

LUBERICATION ENGINEERING : James J.O’connor

BALL AND ROLLER BEARING ENGINEERING: Arvind Palmgren



REFERENCE

WEB-SITES:-

1. www.wikipidya.com

2. www.powersystems.com

3. www.powerengg.com

4. www.protectionofelectricalsystem.com

http://www.wikipidya.com/

http://www.powersystems.com/

http://www.powerengg.com/

http://www.protectionofelectricalsystem.com/



http://www.powerengg.com/

http://www.powersystems.com/

http://www.wikipidya.com/

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