IT Report Keltron

GOVERNMENT ENGINEERING COLLEGE

SREEKRISHNAPURAM

PALAKKAD - 678633

INDUSTRIAL TRAINING REPORT

OF

SHYAM. M

ROLL NO : EPAMEEC055

Undergone at

KELTRON ELECTRO CERAMICS LIMITTED, (KECL)

KUTTIPPURAM, KERALA

(From 16/06/14 TO 21/06/14)

DEPARTMENT OF ELECTRONICS & COMMUNICATION

ENGINEERING, AUGUST 2014

GOVERNMENT ENGINEERING COLLEGE

SREEKRISHNAPURAM

PALAKKAD - 678633

CERTIFICATE

Certified that this report submitted by SHYAM.M bearing roll no-

EPAMEEC055, student of electronics and communication engineering, in

partial fulfillment for the award of the degree of bachelor of technology of

university of Calicut during the year 2016 the training report has been approved

as its satisfies the academic requirements associated with the mentioned degree. Bindu.P Anwar Hussain Dr. S Radhakrishnan

Staff advisor Head of the department Principal Associate Professor Department of electronics and GEC SKP

Department of electronics and Communication

Communication

ABSTRACT

The industrial training is conducted at Keltron electro ceramic limited,

Kuttippuram, (KECL) which is a subsidiary company of Kerala state electronics

development corporation (KSEDC). The objective of the training program is to study in

detail about the various process included in the manufacture of ceramic capacitors,

NTC thermistors and aquatic transducers. The organization and functioning of all the

departments of the company is also studied. The application of various products of the

company is also investigated and included in the appendix of the training report.

The material in this report is organized in a way that provides considerable flexibility

in its reading . Chapter I introduces the history of the company. Chapter 2 carries out a

detailed discussion of the production department of the company. This includes the various

processes in manufacturing ceramic capacitors, NTC thermistors and aquatic transducers.

ACKNOWLEDGEMENT

The satisfaction & euphoria that accompany the successful completion of

any task would be incomplete without the mention of people who made it

possible because "success is the abstract of hard work & perseverance, but

steadfast of all is encouraging guidance''. So, I acknowledge all those guidance

and encouragement served as a beacon light & crowned my efforts with success.

I take this opportunity to convey my sincere gratitude to Mr. Suresh , M.D.

KECL for permitting me to undergo the training at KECl.

I have immense pleasure in expressing thanks to Mrs. Bindu.P AP ECE for

providing all the facilities for the successful completion of the industrial training. Next

I extent my warm thanks to Anwar sir, head of the department of electronics and

communication engineering. I also extend my sincere thanks to all faculty members

and staffs of Government engineering college, Sreekrishnapuram.

Last but not the least, I pledge thanks to my dear friends and family for

pushing me to exceed myself and improving the quality for the work with their

wonderful questions and suggestions.

CONTENTS

1. COMPANY INFORMATION

1.1 KELTRON

1.1.1 Strategic 1

1.1.2 History 1

1.2 KERALA ELECTRO CERAMICS LIMITED

1.2.1 Introduction 2

1.2.2 History 2

1.2.3 Company organization 2

1.2.4 Products of the company 3

1.2.4.1 Ceramic capacitors 4

1.2.4.2 NTC thermistors 4

1.2.4.3 Transducers 4

2. PRODUCTION DEPARTMENT

2.1 Introduction 5

2.2 Manufacturing process of ceramic capacitors 5

2.2.1 Construction 5

2.3 Manufacturing process of NTC Thermistors 10


2.4 Manufacturing process of transducers 18


3. QUALITY ASSURANCE DEPARTMENT 22

4. ENGINEERING 23

5. PRODUCTION PLANNING AND CONTROLLING 24

6. PLANT AND SERVICE DEPARTMENT 25

7. PURCHASE 26

8. HUMAN RESOURCE 27

9. STORE 28

10. MARKETTING 29

11. PROJECT LAB 30

12. APPENDIX A 31

13. APPENDIX B 32

14. REFERENCE 33

LIST OF FIGURES

Fig. 1.1 Organization chart of KECL Fig 2.1 Process flow chart of ceramic capacitors

Fig 2.2 Process flow chart of NTC Thermistor

ABBREVATIONS

AQL Acceptance Quality Level

BIFR Board for Industrial and Financial Reconstruction

D M Water De Mineralized Water

DGM Deputy General Manager

FM Store Finished Goods Store

GR Report Good Receipt Record

HOD Head of the Department

IPA Iso Propyl Alcohol

KECL Kerala Electro Ceramics Limited

KSEDC Kerala State Electronics Development Corporation

LCD Liquid Crystal Display

MD Managing Director

MEK Methyl Ethyl Ketone

NCRB Non Conformation Review Board

NPOL Naval physical and oceanographic laboratory

NTC Thermistor Negative Temperature Co-efficient Thermistor

PVA Poly Vinyl Alcohol

R&D Reasearch and Development

RM Store Raw materials Store

SMPS Switched mode power supply

UWT : Under water telephone

NPL National physical laboratory

Industrial training report

CHAPTER 1

COMPANY INFORMATION

Today we live in a technology- driven world where speed, flexibility

intellectual capital development, network have become the basis of value

creation, as connectivity and interactive technologies pervade all business

activity.

In this technology driven environment, KELTRON finds the assimilation,

adoption and integration of technology in creating innovative solutions as the very

basis of survival. This chapter gives an introduction of KELTRON and one of its

subsidiary company KELTRON ELECTRO CERAMICS LIMITED, KUTTIPURAM. It

also gives a very brief outline of the organization of KECL and its products.

1.1 KELTRON

KELTRON's strength lies in the stable foundation and experience built over the

years, its strong human capital, its nation - wide network and its ability to adapt itself to

change. With over a 35 year long track record as a manufacturer of sophisticated

electronic device and system integration and after sales supporting India.

1.1.1 Strategic vision

To be a world class growth oriented electronics co-operation specialized in

providing quality market focused products, service and cost effective system

solutions to a large clientele.

To attain leadership position in the knowledge industry, by training and

utilizing the rich knowledge capital available in Kerala, and creating a wide

technology horizon for the development of knowledge wares and intelligent systems.

1.1.2 History

KELTRON's is a saga of innovation in electronics. From being a pioneer in

1973, to the role of a trend-setter today.

Dept. of ECE, GEC, Sreekrishnapuram

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The tag line launching a state-owned electronics enterprise, more than a

quarter century ago, read "spearheading an electronics revolution in Kerala''.

It was an experiment by the government of Kerala for its spices, natural

beauty, kathakali and onam boat races, to an arena for industrial and

technological development. That was how KELTRON was born. Within 5 years of its inception, KELTRON had set up a production center in

every district of the state. KELTRON ELECTRO CERAMICS LIMITED is one

of the manufacturing centers of KELTRON

1.2 KELTRON ELECTRO CERAMICS LIMITED

1.2.1 Introduction

The company is situated 3km away from kuttippuram town in Malappuram

district, Kerala state, along the national highway nestling the bangs of the river

bharathappuzha in a scenic setting. The landholding of about 20 acres provides

excellent scope for setting up of manufacturing facilities and for further development.

1.2.2 History

The company was incorporated in the name ''DIELECTRO MAGNETICS

LIMITED'' as a joint venture between Kerala state electronics development

co-operation limited (KSEDC) and a team of technocrats on 23rd April 1974

for the manufacture of ceramic capacitors. It becomes a subsidiary of KSEDC

in 1977. Later in 1985 its name was changed to KELTRON ELECTRO

CERAMICS LIMITED. In 1983, the management of the company was taken

over by KSEDC which took step for rejuvenating the company. Production of

disc ceramic capacitors was started during 1978 using NPL technology. The

company is also manufacturing negative temperature coefficient thermistors

(NTC Thermistors) based on its in house R&D and transducers for defense. The company was plagued with several technical and commercial

bottlenecks initially and the operation was not profitable. Consequent on the complete

erosion of net worth, the company was referred to board for industrial and financial

reconstruction (BIFR) in January 1993. Under BIFR, a revival package was successfully

implemented with assistance of holding company KSEDC, the operating agency canara

bank and the wholehearted support of all employees. As a result, the company came

out of the purview of BIFR during December 1996 ahead of schedule.

The products manufactured by KECL are marketed by KSEDC. KECL is paying

5% selling commission to KSEDC. For this KSEDC is having corporate marketing

department at Thiruvananthapuram which is controlling the marketing Activities.


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1.2.3 Company Organization

KELTRON ELECTRO CERAMICS LIMITED has a managing director with heads of various departments reporting to him. 1. Production department 2. Quality assurance department 3. Purchase department 4. Marketing department and 5. Finance and accounts department

The functioning/ duties of each department will be covered in the

coming chapters.

The organizing chart of KECL IS shown in figure 1.1

MD

HOD DGM DGM DGM HOD (Finance &

(Materials) (Production) (Quality) (Marketing) accounts)

In charge HOD HOD HOD Engineer staff Staff

(stores) (DIV I) (DIV II) (DIV III)

Engineer Engineer Engineer

Staff Workmen

Workmen Workmen Workmen


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1.2.4 Products of the company

KECL was the market leader in manufacture and sale of ceramic capacitors,

NTC Thermistors, metal oxide varistors and buzzers. But due to globalization,

privatization and liberalization manufacture and sale of metal oxide varistors and

buzzers become in huge loss. So KECL stopped the manufacturing and selling of

these two products and they started transducer manufacture for NOPL. Now KECL

products are used in industrial, professional and consumer electronic equipment’s. 1.2.4.1 Ceramic capacitors

Ceramic capacitors are used for applications in consumer

electronics, telecommunications, automobile and other professional

electronic equipment’s. These components are available in Class I, Class

II, Class III types with working voltage ranging from 16 V to 2KV 1.2.4.2 NTC Thermistors

NTC Thermistors has been developed in - house and find wide

acceptance in automobile, in -rush current protection areas such as electronic

ballast and SMPS and for temperature compensation in electronic circuits.

1.21.4.3 Transducers

Transducers manufactured by KECL are electro mechanical devices based

on the principle of Piezzo electric effect. Transducers can transit ultrasonic sound

and also are able to receive sound signals from other sounds in under water. The manufacturing details of all these products will be explained in chapter 2.


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CHAPTER 2

PRODUCTION DEPARTMENT

This production department of every company has a greater influence on the

overall functioning of the organization. This chapter describes the functioning of

production department of KECL and the manufacturing of various products of KECL.

Production department is divided in to three divisions are concentrating on

the three products mentioned in the earlier chapter. As evident from the

organization chart head of the production department is DGM (Production), who

is assisted by engineers, plant supervisors and senior technicians. The production process is as follows:

The production planning and control department receives the indent for one or three

months from marketing department on the basis of consumer's demand . The one month

sale indent is firm and there will not be any change. According to the stock statement of raw

materials and finished goods, production planning and control department gives production

indent and work order to production department. Production department will draw raw

materials from the store and converts it into finished goods.

2.2 manufacturing process of ceramic capacitors.

KECL's one of the fast moving product is ceramic capacitor. The company

has been manufacturing this item for over 35 years and has been distributing all

over the country. KECL offers a wide range of low cost disc type ceramic

capacitors for applications in television, two-in-one, VCR, communications, push

button telephones and other professional electronic equipment’s. The range includes

Class I - Temperature compensating Class II - High dielectric compensation Class III - Semi conductive type

These are designed for high insulation resistance, low power dissipation, good

dielectric strength and perfect hermetic sealing and available in a range of voltages.

2.2.1 Construction

construction of ceramic capacitor consists of the following processes.


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1. Looping 2. Disc loading 3. Soldering 4. Encapsulation 5. Baking 6. Aging 7. Value marking 8. Testing

Details of each steps is as given below

Looping (lead form)

This is the first stage of ceramic capacitor manufacturing. This is also called

lead forming. The materials used to make the lead for ceramic capacitors are

Tinned copper wire Paper base crepe paper tape

In this process a tinned copper wire is introduced serially in strip of paper

base. The raw materials used in this process are tinned copper wire, paper base,

crape paper tape. In this machine a thick paper base came, tinned cu wire is cut

and bend, and then introduced above the thick paper. At the same time a stickly

crape paper will fix the cu by pressing it over the thick paper and cu. this

continues paper strip is cut at a certain length. This process is known as looping.

Disc loading

In this process a disc is inserted in between the needle of the capacitor

legs. Disc is a material of ceramic piece, the two sides of this piece is coated with

silver. This is done by a vacuum pump.

Soldering

Now the assembly is dipped into flux. (The materials used as flux are Iso propyl

Alcohol (IPA) and rosin in the ratio 1 lit: 10gm. This step is known as flux dipping, which is

carried out prior to soldering process. Dipping time is 3 sec (max). Then the disc is pre-

heated about 80 degree Celsius -120 degree Celsius. This is done to avoid chances of

getting crack to disc at sudden temperature rise during soldering. Next step is soldering.

Using lead and tin soldering is carried out at a temperature of 200 degree Celsius with a

tolerance of 10 degree Celsius. The soldering bath temperature should be uniform at all

places in the bath. Maximum variation of temperature at different points in the bath shall be

within 2 degree Celsius. Next step is cleaning or washing. Cleaning is done by using IPA.


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Encapsulation Next step is encapsulation. The material used for encapsulation is Resin.

Resin is prepared as follows. Industrial solvent - acetone mixture in the ratio 3:7 is preferred. 25 kg of Durez

resin is taken in the mixing jar and 10 liters of solvent mixture is added to it. Methyl ethyl

ketone (MEK) is also added to it and the mixing jar is mixed for approximately 8 hours.

Coating is done by dipping the silvered ceramic disc into this resin for 3 second.

Air curing

Next step is air curing or blowing of dry air. This is done to remove the solvent.

Baking

Baking is done in a baking oven which is maintained at 135 degree Celsius for 1½

hour.

Ageing

After baking the capacitor shall be stored under normal room temperature for aging.

Ageing is required because due to baking the value of the capacitor will change from actual

value. The time taken by the capacitor to return back to actual value is period. Ageing period for capacitors processed in semi auto line is as follows. Class I type : minimum 24 hours after baking process. Class II & Class III minimum 3 days after baking process. Value Marking

Marking is done according to marking specification. This standard specifies

the marking codes used to identify different types of ceramic capacitors. ceramic capacitor will be marked to identify the following Company logo

Capacitance value

Working voltage

Temperature characteristics Company logo

Letter ''K'' will be used to identify the company.


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Capacitance value

Capacitance value will be expressed in Pico farads. For capacitance below

100 Pico farads, the value figures will be given. E.g. 1.2 Pico farads - 1.2.

Working voltage

Working voltage will be identified by alpha codes as follows. 160V DC - letter ''L''

30 V DC- letter ''M''

500V DC - no letter

1000V DC - letter ''P''

3000V DC - letter ''T'' Temperature characteristics

Temperature characteristics will be identified as follows. NPO type - letter ''C''

N750 type - letter ''U''

Y5E type - letter '' A''

Y5V type - letter '' F''

The capacitor values are marked using acetone and painting ink. Testing

The finished capacitors will be taken for testing to assure the quality. Details

of quality checking will be explained in the next chapter. After that it is transferred

to finished goods store for packing and storing. The process flow chart is as shown in the Figure 2.1. Application and different types of ceramic capacitors made by KECL are given in appendix A.


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2.3 manufacturng process of NTC thermistores

NTC thermistores are thermally sensitive resistores with a high negative temparature

coefficient of resistance. For thermistores of a given composition, the measurement of a

specific temperature will induce a specific resistance across the thermister. This resistance

can be measure of the temperature. Various thermistores made of oxide of nickel,

manganese, or cobalt is used to sense temperature between 46 degree centigrade and 150

degree centigrade. NTC thermistors have been developed in - house and find wide

acceptance in automobile, in-rush current protection areas such as electronic blast and

SMPS and temperature compensation in electronic circuts. 2.3.1. construction Manufacturing of NTC thermistor consists of the following steps.

1. First milling 2. Oven drying (pre firing) 3. Second milling 4. PVA dilution 5. Granulation 6. Tabletting 7. Sintering 8. Disc cleaning 9. Screen printing 10. Silver firing 11. Disc checking 12. Assembling 13. Encapsulation 14. Air curing 15. Baking 16. Aging 17. Sorting 18. Value marking 19. Testing 20. Packing

Details of each steps is as given below.

First Milling

Apparatus used in this step are

1. Tolaman weighing balance with weight

2. S.S jar


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3. Alumina balls 4. Jar mill 5. Measuring jar 6. S.S tray with strainer 7. Drying oven

Materials used are Manganese carbonate

Nickel carbonate

Cupric oxide

D.M

water Procedure

1. Clean the S.S. jar and alumina grinding media first with tap water

followed by D.M water

2. Weigh the chemicals as per the quantities mentioned in the log book

and put them into cleaned jar

3. Weigh cleaned grinding media equal to twice the weight of the total

chemicals taken and put them into the jar

4. Add D.M water in the ratio 1:1 W/V to that of total chemical taken. 5. Close the jar, check for leakage and place it on the jar mill. Mill the

contents for 4 hours

6. After 4 hours stop milling and pour the slurry through a strainer into

the S.S tray. 7. Keep the contents of the S.S tray in the drying oven at 120o C and allow it

to dry about 12 hours for the water to get completely evaporated. 8. Clean the grinding media for after use.

Pre-firing Now pre-firing is done. The procedure is as follows:

1. Clean the mesh and keep it in the oven at 1200C and allow it to dry

about 12 hour for the water to get completely evaporated.

2. After completing drying, fix the mesh in the granulator. 3. Place a S.S tray below the mesh. 4. Feed the dried chemical mixture in the form of cake on the top of

the mesh and switch on the granulator.

5. Switch off the granulator and take out the tray. 6. Set the temperature to 9000C 7. Allow soaking time of 2.5 hours and switch off the furnace at the end

of 2.5 hours.


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Second milling

Materials Used 1. Pre-fired chemical mixture 2. Cupric oxide 3. D.M water 4. Filter cloth and paper

Procedure Take out the pre-fired mixture from the pre-firing furnace and allow it to

cool to room temperature.

Weigh the mixture using Tolaman balance

Put the mixture into the jar and add alumina balls equal to two times that of

mixture weight

Put the jar on the rollers of the mill and take out the jar.

Filter the contents of the jar

Take out the cake from the filtering unit and put the same into the tray and place

the tray into the baking oven at 1200C for about 12 hours till complete removal of

water. Drying is required because otherwise granules will not be formed. PVA Dilution Materials used:

1. Poly vinyl alcohol (PVA)

2. D.M water Procedure Place the magnet in the beaker. Keep the beaker with water on the magnetic

stirrer. Switch on the heater.

When the limb is about 650C - 700C, Place slowly to the water. If necessary

adjust the heat switch to maintain the limb at 650C - 700C.

After adding all the 40 gram of PVA to the water continues stirring for about one hour.

Switch of the heater.

Granulation Material used

1. Dried cake from second milling operation.


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2. Diluted poly Vinyl Alcohol Procedure Clean the granulator and sigma mixer. Take out the cake from oven and allow

it to cool. Weigh the cake and put the cake in sugma mixer and switch ON the

sigma mixer. Wait till the cake is completely converted into power form.

Take diluted PVA and slowly add in the sigma mixer.

Stop the sigma mixer and take the dough. Split the dough into small portions and place it

into the tray. Put the dried lumps into the granulator and switch on the granulator.

Stop the granulator once the grinding is complete and keep the granules in the

oven at 1200 C For 2.5 hrs. Tableting (forming the disc) Materials used

1. Row material mix in the form of granules. Procedure Remove the feed frame and clean the torret with acetone.

Remove the front guard and body plug. Also remove the stopper of the selected die.

Clean the die using acetone and insert the lower punch. Replace the body

plug. Rotate the flywheel manually and when the lower punch reaches the

eject portion adjust the height of the punch to flush the surface of the forret.

After this adjustments switch on the tableting machine. Now we can collect the

disc from the tableting machine. Sintering Materials used

1. Green tablets

2. Zirconium oxide power

Procedure

Clean the alumina sinforing tray and a wooden scrapper to remove any Zirconium

powder sticking to it. Spread a thin layer of fresh Zirconium oxide over the disc.

Load the tray into the sintering furnace and close the door.

Set the transformer tabbing to 2-1 and temperature in the controller to 3000 C

and switch ON the powder supply to the furnace.

After half hr soaking at 3000C set the temperature of the furnace to 6000C


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After soaking for 3 hrs. at the sintering temperature switch OFF the furnace.

Allow the furnace to cool overnight.

Disc cleaning Materials used

1. Sintered disc

2. Zircon sand

3. Acetone

Procedure Put the disc into the porcelain jar. Add Zircon sand and close the jar and place

it on the j a r mill. Mill the contents. After the milling inspect the disc for

complete removal of Zirconium Oxide.

Transform the cleaned disc to the S.S. Jar.

Screen printing To lay down the procedure for electroding of sintered disc. Materials used 1. Sinterred and cleaned disc. 2. Silver The disc is coated with silver oxide. This is Known as screen printing

Silver firing Silver firing means heating the disc at 8000 C to remove oxide

Disc Checking

Place the disc ready for sorting on the metallic platform which is kept

inside the A/C room and allow them to attain room temperature. Also place the

resistance disc on the platform. Check the temperature of the plate indicated by

the thermometer. When the thermometer reads 250 C, check the value of

standard resistance. If resistance value of the standard disc matches with the

specific value at 250 C, start sorting the disc as per specification.


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Assembling

Now the next phase is assembling. i.e., soldering tinned copper wire to the

disc. This process includes looping, soldering, and cleaning. Encapsulation (coating)

Next step is encapsulation. The material used for encapsulation is resin.

Resin is prepared as follows.

Industrial solvent - acetone in the ratio 3:7 is prepared. 25kg of durez resin is

taken in the mixing jar and 10 liters of solvent mixture is added to it. Methyl ethyl ketone

(MEK) is also added it and the mixing jar is closed and mixed for approximately 8 hours.

Coating is done by dipping the silvered disc into this resin for 3 seconds.

Air curing

Next step is air curing or blowing of dry air. This is done to remove the solvent.

Baking

In this step the thermistor is kept dry for 24 hours. Then it is baked for 1.5

hours at a temperature of 1350 C - 140 0C. Aging

After baking NTC thermistor shall be stored under normal temperature for again .Again is required because due to baking the characteristics of the NTC thermistor

will change from actual characteristics the time taken by the NTC thermistor to

return back to actual value is again period. It takes approximately 72 hrs. Sorting

Keep the lead cut thermistor strip in the A/C room and allow thermistor to attain

room temperature. Keep the thermometer over the strips. When the thermometer reads 25 0 C start sorting of the thermistors as per the

value of the standard resistance. Mark the ones which were out of the tolerance.

Value Marking

The final step is value marking. Marking is done according to the printing ink and

acetone is used in this step.


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Testing

The finished thermistors will be taken for testing to assure the quality.

Procedure

1. Clean the jig using acetone and allow it to dry. 2. Fill the silicon oil in the beaker to 60 % of its capacity. 3. Cross check the connections and the strip connector. 4. Place the thermistor disc into the jig and place the jig in silicon oil. 5. Heat the oil to 1200 C 6. When the temperature attains 1200 C stop heating and allow to cool naturally. 7. Record the resistance values at different temperature starting from 1200 C to 400 C

After quality checking will it is transferred to Finished Goods store for

packing and storing. The process flow chart is as shown in Figure 2.2 Applications of NTC Thermistors manufactured by KECL are given in Appendix B.


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2.4 Manufacturing Process of Transducers

Measurements of mechanical, thermal, electrical and chemical quantities new made

by devices called sensors and transducers. The sensor is responsive to changes in the

quantity to be measured. For Example temperature, position, pressure or chemical

concentration. The transducer converts such measurements into electrical signals, which

can be fed to instruments for the readout, recording or control of the measured quantity.

Sensors and transducers can be operated at remote locations from the observer and in

environments unsuitable or impractical for human beings. In pressure transducers in out

vibrations are converted to electrical signals. The application of transducer includes under

water communications and other naval applications.

In this division different types of transducers are manufactured. Here, the

transducers produce will covert aquatic energy into electrical energy and vice versa.

The main component used is piezo ceramic material are arranged in three groups.

1. Hard materials

The type of material can withstand high levels of electrical excitation

and mechanical stress.

E.g.: PZT -4D (Navy Type I)

PZT - 8(Navy Type III)

2. Soft material

This type of material are characterized by high sensitivity and

permittivity, but under high drive conditions are susceptible to self - heating

beyond their operating temperature range.

E.g.: PZT -5A ( Navy Type

II) PZT - 5J (Navy Type

V) PZT - 5H (Navy type

VI) PZT - 5R

3. Custom material

Several ceramic materials have been formulated to meet particular

needs of specific applications.

E.g.: PZT - 7A

PZT - lead Titanate 2.4.1 construction

Facilities available at KECL for transducer manufacturing are 1. stacking press -2 No's 2. LCR meter with PC


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3. Jigs & Fixtures for stacking PZTs for UWT, Dual UWT, Hanet, cylindrical

transducer array, FT Transducers, Hydro phone with amplifier, seismic hydro

phone with amplifier, seismic hydro phone etc. 4. Audio amplifier, speaker system, PC, oscilloscope, function generator, high

resistance meter etc for testing hydro phones etc. 5. Biasing setup. Manufacturing steps of transducer is as follows. 1. PCT evaluation 2. Stacking 3. Evaluation 4. Torque application 5. Evaluation 6. Molding 7. Evaluation 8. Tuning 9. Final evaluation PCT Evaluation

The single crystal is polarized (poled). The process that induces piezo electrical

properties in the ceramic is known as " poling''. The process of applying high electrical

field (in the range of IK to 10K) to ceramic element is know n as poling. The poling

process permanently changes the dimensions of a ceramic element. The orientation of

the dc poling field determines the orientation of the mechanical and electrical axes.

After the poling process is complete, a voltage lowers than the poling voltage

changes the dimensions of a ceramic element for as long as the voltage is applied. A

voltage with same polarity as the poling voltage causes additional expansion along the

poling axis and contraction perpendicular to the poling axis. A voltage with opposite

polarity has the opposite effect. In both cases, the ceramic element returns to its poled

dimensions when the voltage is removed from the electrodes.

For polarizing a polarizer is used. Now using LCR meter the C value, than ø,

resonant frequency and conductance of the ceramic element is measured. Stacking

Next the poled ceramic elements are stacked. The number of ceramic elements

sacked depends on the application. Stacking is need because a single ceramic

element produces very high frequency. To reduce the fervency of operation stacking is

needed. As weight increases frequency decreases. Dept. of ECE, GEC, Sreekrishnapuram

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Single ceramic element is stacked using specific type of adhesive cement.

(e.g.: Thumba cement) and by applying a high pressure (80kg.cm2) for 24 hours.

Now the stack is cleaned using acetone. Again using LCR meter the C

value, tan ø, resonant frequency and conductance of the stack is measured.

Torque Application and Molding

Now the assembly is pre stressed between two metallic masses (one is called

head mass and other tail mass. The weight of head mass will be very much less than

tail mass) and the entire assembly will be encapsulated. Fiber reinforced plastic is

used for insulating the stack assembly from he metallic mass. Tuning

Tuning is done using ferrite core and enameled CU wire. This is to make the

device ready for use. After tuning the final evaluation will be carried out. The process flow chart is as shown in finger 2.3

The transducers are manufactured in various designs to cater to the needs of Indian

navy. These are used for under water communication, detection of mines and other obstacles.


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Fig 2.3: process flow chart of transducers

PCT

evaluation

Stacking

Evaluation

Torque

application

Evaluation

Molding

Evaluation

Tuning Tuning

Final Evaluation


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CHAPTER 3 QUALITY ASSURANCE

In this the quality is measured. Five types of inspections are there, they are

1. Invading inspection

2. Raw material inspection

3. In process inspection

4. Patrolling inspection

5. Final QA inspection

Some types of inspections are described below : Raw material inspection : the raw material is inspected. There have a good receipt and report.

The good receipt contains supplier, department, inspected by quantity of accepted & rejected. In process inspection : The daily checking of goods and products come under the

section. machine clearance, dimensions and others are recorded in this. Final QA inspection : The final checking of products. Mainly done at FG store.


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CHAPTER 4 ENGINEERING

in this department the planning of new products are done by engineers and HOD's of each department. For production of new element, we have to make BOM (bill of material). The whole engineering process contains drawing, data collection, market of the product.


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CHAPTER 5 PRODUCTION, PLANNING AND

CONTROLLING

The main function of this to co - ordinate he production, planning and controlling. There are certain records keeps in the PPC department. They are sales quantity record, red reference record, store keep record, store quantity record. All are come under sales PPC. Similarly there marketing PPC, Material PPC also.


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CHAPTER 6 PLANT AND SERVICE DEPARTMENT

The section is for repairing the machines and providing the power to the whole

industry. Two types of maintenance are there, preventive maintenance, and break down

maintenance. A Machine failure report book is kept in the department; the complaint can

enter in it. It will show date, department, complaint, record, signature and time. There is

a switch room for power supply. if power failure occurs then the generator will work, it

can provide 50Hz 440 v. the monthly current bill will be around 70,000 rupees.


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CHAPTER 7 PURCHASE

When the PPC department demand for certain material, this department has the responsibility to get it. First of all company will accept the quotation from different approved vendors. After getting the rate, the total expense is calculated. And give purchase order to the company , which has least expense includes sales tax, excise duty, packing and forwarding charge.

`If a new vendor comes, the company tests materials, after that, the vendor assessment committee will decide, whether the vender is an approved vender.


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CHAPTER 8 HUMAN RESOURCE

A company will look up for the maximum output from a worker. If the company

has vacancies, the department gives the advertisement through newspaper or internet.

Next is screening of application, test, interview, and selection. The placed candidate will

give induction training. This period is known as probation period. After this period he will

be a confirmed employer. He will get promotion based on his performance appraisal.

And other benefits are given like TA (traveling allowance), DA etc.


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CHAPTER 9 STORE

Two types of stores are there, raw material store and finished goods store. In RM store the

raw materials are stored. The stock is checked according to nature and quantity of material. The

stocks are arranged as per its bulkiness, weight, breakage etc. There have a ledger, closing stock

statement. The ledger contains opening balance, receipt, issue and closing balance. ?In finished

goods store the finished products are stored. The first in first out is used in FG store.


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CHAPTER 10 MARKETING

Sales mean the selling of products only. But marketing means advertisement, contacts,

along with sales. Without marketing sales cannot be achieved. The main sales of KECL are to

Mumbai, Chennai, Ahmadabad, Delhi, Kolkata, and Bangalore, Since KECL is a Govt company,

they are not giving any advertisement, they giving direct contact through internet and telephone.

Two types of customers are there - OEM (original equipment manufacturing ), and dealers.


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CHAPTER 11 PROJECT LAB

In project lab, mainly deals with embedded system lab. To. do programming we use MPLAB

software, and used high tech C language. Studied about micro controllers and its programming.


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APPENDIX A Different types of ceramic made by KECL

KECL offers a wide range of low disc type ceramic capacitors for applications in

television, VCR communication purpose, push button telephones, and other

professional electronic equipments.

There are mainly three classes of ceramic capacitors manufactured by KECL.

They are as follows : Class 1- Temperature compensating

These capacitors are particularly suitable for applications where high quality of

capacitance and small losses are required. Besides they offer the property to have a

linear capacitance change Vs temperature. They have the property of linear

temperature coefficient of capacitance and high stability.

Applications : any circuit which requires frequency control E.g.: 50V, 500V/NPO, N150, N750 and series Class 2 - high dielectric constant These capacitors are distinguished by a high specific induction power (greater than 1000),allowing

the manufacture of large capacitance with small size. They are particularly suitable for filtering and

decoupling. They offer the property to have a limited change of capacitance value VS temperature. Applications : as bypass and coupling capacitors in various amplifier and

oscillator circuits. E.g. : 50V, 500V/Y5P , Z5V series

Class 3 - Semiconductor type

These capacitors are characterized by linear temperature coefficient of capacitance.

They offer low losses at wide range of frequency. Ultra large capacitance is achieved in

small sizes. The capacitance change is stable over specified temperature. Applications : Bypass and coupling in different

circuits. E.g.: 16 V, 25V, 50V/Y5R, Y5P, Y5V series


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APPENDIX B

APPLICATIONS OF NTC THERMISTORS TEMPERATURE SENSING

Thermistors find wide applications for temperature sensing. It is used in

refrigeration and air conditioning equipment. This is also applicable in automobile

radiator temperature sensing and thermostats.

TEMPERATURE COMPENSATION

These capacitors are particularly suitable for applications where high quality of

capacitance and small losses are required. Besides they offer the property to have a

linear capacitance change Vs temperature. They have the property of linear

temperature coefficient of capacitance and high stability.

Applications : any circuit which requires frequency control E.g.: 50V, 500V/NPO, N150, N750 and series Class 2 - high dielectric constant These capacitors are distinguished by a high specific induction power (greater than 1000),allowing

the manufacture of large capacitance with small size. They are particularly suitable for filtering and

decoupling. They offer the property to have a limited change of capacitance value VS temperature. Applications : as bypass and coupling capacitors in various amplifier and

oscillator circuits. E.g. : 50V, 500V/Y5P , Z5V series

Class 3 - Semiconductor type

These capacitors are characterized by linear temperature coefficient of capacitance.

They offer low losses at wide range of frequency. Ultra large capacitance is achieved in

small sizes. The capacitance change is stable over specified temperature. Applications : Bypass and coupling in different

circuits. E.g.: 16 V, 25V, 50V/Y5R, Y5P, Y5V series


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REFERENCES

1. www.keltronelcera.com 2. Product catalogs of KECL


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Documents

IT Report Keltron