Electrical Training Report

7/29/2019 Electrical Training Report

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TRAINING REPORT

ON

ELECTRICAL

IN PARTIAL FULFILLMENT FOR THE DEGREE

OF ELECTRICAL ENGINEERING

AT

BALLARPUR INDUSTRIES LIMITED

Unit Shree Gopal, Yamuna Nagar

Under Supervision Of: Submitted By:-

Mr. SANJEEV VOHRA Dheeraj Chopra

Submitted To:- 2208713

Electrical Dept. ELECTRICAL(3rd Year)

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PREFACE

Practical training is an important part of theoretical studies. Itcovers all that remains uncovered in the classroom. It offers

the student to exposure an invaluable treasure of

experience. It offers an exposure to real practical of

instruments in the industries.

As we know that practical training plays an important role in future

building of an individual. One can easily overcome the fear from

that life in which he has to join a member after some time.

Just theoretical knowledge is not sufficient for the success of an

individual so one should have practical knowledge about eachtheory general life. The training greatly enhance our knowledge

and provide good opportunities to blend our theoretical as well as

trainees get familiar with certain aspect of industries like shop floor

management, production, process and industrial relation etc.

I feel proud to get training at BALLARPUR INDUSTRIES LTD,

YAMUNANAGAR that is one of the tops most paper

manufacturing industries in India.

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ACKNOWLEDGEMENT

This report conveys my heartiest thanks to all those officers and

employees of THAPAR GROUP who have given me their full co-

operation and devoted their valuable time, for rendering me their

needy services, guidelines during the course of imparting me

practical training and with those sincere and precious help I have

been able to complete my practical training successfully.

I wish to express my sincere gratitude to

Mr. SANJEEV.VOHRA for providing me the training facility.

I also like to thank Mr.MUKHERJEE and Mr. PRAKASH

SHARMA (HR DEPTT) for their valuable support.

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INDEX

1)Introduction

2)Infrastucture

3)Departments

4)Power House

5)Coating Plant

6)Process Of Power House

7)Speciality Plant

8)Chipper House

9)Programable Logical Control(PLC)

10)Distributed Control System(DCS)

11)Conclusion

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INTRODUCTION TO BILT

BALLARPUR INDUSTRIES LIMITED, popularly knownas BILT is efficiently managed, financially sound, and self

sufficient and self made company is

The flagship of the covetedTHAPARGROUPS.

The ThaparGroup is one of the leading business houses in India. It hasa turn over of Rest 5000/- Crores BILT is one of the leading

companies with in the Thapar Group.

The Thapar Group has a wide range of activities like paper,

engineering, electronics, textiles, chemicals, glass,

telecommunications, biotechnology, leather etc.

There are 54 companies and 84 plants under this group. Some of the

main companies under this group are Crompton Greaves, K.C.T &

Bros. Limited, JCT Limited, BILT.

Ballarpur Industries Ltd. (BILT) promoted by LM Thapar, isthe leader in Indian paper industry with an annual production capacity

of 460000 MT spread over in five manufacturing facilities produces

ordinary and superior varieties of writing, printing and specialty papersetc. The company is also backwardly integrated with its

Caustisoda/Chlorine manufacturing facility, which is a vital material

consumed in the production process of paper.

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BILT, which is originally incorporated in 1945 as Ballarpur Straw

Board Mills, has changed its name in March 1946 to Ballarpur

Paper and Straw Board Mills and again it was changed to the

present name in Oct. 1975. Since then the company has grown tobe a leader in paper industry by continuous expansion andmodernization of its capacity and plant and strategic acquisitions. In

1969 the company has merged Shree Gopal Paper Mills with

itself and the company which has acquired the Sinar Mass Pulp

and Paper (India) Ltd. (now BILT Graphic Papers Ltd.)

The company which was one of the most diversified companies in thepre-liberalization era of industrial licensing with interests in Paper,

Chemicals has decided to focus on its core competence that is inpaper and exit from its non-core businesses. First major steps on theselines were initiated in the year 1994-95 with hiving off the glass

business. Thereafter the company sold its vanaspati and edible oils

business in 1996-97. And in 1998, the chemical division of thecompany with its plant at Karwar, Karnataka and which has interests

in Phosphates, Chlor Alkali and Bromine and Bromine Chemicals was

spun of into a separate company that is Ballarpur Chemicals Ltd (nowSolaris ChemTech Ltd). To complement its Restructuring and to enable

it to emerge as a stronger and more competitive organization, thecompany is implementing a project involving modernization and

expansion of capacity at its Units in Shree gopal, Ballarpur and

Sewa by 105000 TPA. The Project will be implemented in twophases.

In the first phase, the capacity expansion of 35000 TPA and 28000TPA is planned over a two-year period from 2000-01 to 2002-03 for

Units Sewa and Shree Gopal. In the second phase 42000 TPA

of capacity is expected to come on stream at Unit Ballarpur by 2003-04. During the year 2001-02, the company has completed the upgradation of pulp mill at unit Sewa resulting in increase in capacity by

37 tones from the earlier 125 tones of unbleached pulp per day. The

company has also completed the installation of a 2.4 meter wide

blade coater at Unit Shree Gopal in FY2001-02. BILT enteredinto strategic alliance with Hansol of South Korea to provide world

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class blade coated paper to the Indian customer. it is the first company

in the world to commercially exploit the fractionation of bamboo andhas applied for the world patent for this process. It has also entered

into direct retail distribution with the launch of A4 size, 100-sheet

pack of Royal Executive Bond

Mr. Gautam Thapar, Managing Director of BILT, has beenassociated with BILT since 1986 when joined the company as Shop

floor Management Apprentice-Paper Mills and was instrumental inturning around BILT in the late 1990s.

Thapar Paper Group Consists Of Five Units:

1. Ballarpur Unit, Distt. Chandrapur, Maharastra.

2. Shree Gopal , Yamuna Nagar, Haryana.

3. Ashti, Maharastra.

4. Bhigwan, Maharashtra

5. Sewa, Orissa

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INFRASTRUCTURE

Founder - Late Lala Karam Chand Thapar (1900-1962)

Consist of major industries such as paper, chemicals, glass,

pulp, china clay, electronics etc.

Lala Karam Chand acquired Shree Gopal Paper Mill in 1936 ashe already established himself as a coal king.

Shree Gopal Paper Mill earlier know as M/S Panjab Plup and

Paper Company which was initially promoted by Foundation

Company England, the mill was laid shut for 6 month andwas ultimately auctioned.

This unit consists of:

Six paper machine machines.

Two coating plants.

Three finishing houses.

Two power houses. One caustic soda plant.

New pulp mill.

CHSR.

At present Unit - Shree Gopal is producing around 250 TPD ofpaper.

Total Area - 206 Acers.

Factory Area - 155 Acers. Colony Area - 51 Acers.

Turnover - Rs 24-26 Crores / month.

Manpower -:

Managerial staff 230

Permanent workers 1560Casual workers 740

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Clerical 146

DEPARTMENTS

The departments are categorized as

Administrative department

PDC People development and communication.

Accounts Department.

Material Department.

Sales Department.

Raw material Department.

Traffic Department.

Process Department Mill

1. Pulp Mill2. Machine House.

3. Coating Plant.

Engineering Department

a. Electrical engineering.

b. Mechanical Engineeringc. Civil Engine

d. Instrumentation Engineering

e. Power House.

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POWER HOUSE

This section of workshop undertakes the maintenance of: -

1. High pressure boilers No. 1,2 and 3(steam pr 85Kg/cm2)

2. ABL Recovery Boiler No. 4

3. JMW Recovery Boiler No. 5

4. Low Pr. Boiler No. 6 and 7

5. T.G Turbine

6. BTH Turbine

7. Black Liquor Evaporation Section

8. Chemical House

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COATING PLANT

This section workshop undertakes the maintenance of: -

1. Colour Kitchen

2. Coating Machine

3 Super Calendar

4 Rewinder

5 Laminating Machine No.1.2 and 3

6 Cutter 1&2

7 Wrapmatic Machine

8 Bundling Machine

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DIFFERENT SECTION

1)SPECIALITY SECTION


1 Paper Machine No. 5,6 and 7

2 Effluent Treatment Plant

2) PULP MILL SECTION


1. New Pulp Mill

2. New Chipper House

CLO2 PLANT

1. CLO2 section

2. O2 section

3. SO2 section

4. Vapourizer section

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PROCESS OF POWER PLANT

POWER HOUSE

In the Power House, electric power is generated to meet the

demand of electrical energy for running the plant. The powerhouse

can be divided into the following main sections:-

1. Water Treatment Plant (D.M Plant)

2. Coal fired boilers section

3. Recovery boilers section

4. Turbines section

The detailed description of these sections is as follows: -

1,Water Treatment Plant:

In this plant, water is purified so as to make it usable for the

boilers. The water, which comes from the pump house, has

the hardness of approximately 200-250 and conductivity

around 300-600 mho. This water with the help of feed

pumps is fed to the reaction tank where it reacts with lime to

remove the hardness of water. The reaction-taking place is: -

Ca (HCO3) 2 + Ca (OH) 2 CaCO3 + H2O

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Precipitates settle down and water is collected from overflow

in some adjacent tank. Now, the water is sent to the pressure

filter, where calcium carbonate is taken as filter medium.

After pressure filter, the hardness of water decreases to 50-

60. Now, this water is passed through the cation exchanger.

In the cation exchanger, cationic impurities are removed.

Cationic exchanger is charged with HCL every twenty-four

hours. Then, the water flows to the De-gasser. Here, water is

showered from the upper side and air is pumped fromdownwards. When the air strikes with water droplets, it takes

the gas along with it. After this, the water goes to the weak

Base Anion Exchanger, where strong anionic impurities are

removed. The next is the Primary mixed bed, where the

remaining cationic ND anionic impurities are removed. This

water is now stored in the D.M tank. The condensates of

steam are also brought to the same tank after passing through

charcoal and iron filters. To ensure the required standard of

de-mineralized water, the water is taken to the secondary

mixed bed. Ammonia is dozed in this water so as to increase

the pH to about 6.8-6.9. Now, this water is sent to the boilersfor steam production.

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( OverView Of Steam Turbine)

2.Boiler section: -

The boiler section has two main parts: -

1. Coal fired boilers

2. Recovery boilers

2.1.Coal fired boilers

The coal-fired boilers are of two types:

a) High pressure

b) Medium pressure boilers

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Out of total seven boilers, Boiler No 1,2 and 3 are H.P. Boilers;

Boiler No. 6 & 7 is M.P boilers and ABIL & JMW are the two

recovery boilers.

In the boiler, the steam is produced in the following manner.

Water comes to the steam drum from the P.D.M tank. This tank is

surrounded by steam line due to which inlet water temperature is

approximately 48C. Here, morphine is dozed in the water, so as to

laminate the pipes internally to increase the life of pipelines. The

water is then taken to the Derator Tank. In the Derator Tank, wateris showered from the upper side and steam is taken from the

bottom side. This steam removes the air and increases the

temperature of the feed-water. In the Derator Tank, hydrazine is

dozed for the reaction with oxygen in the air. The reaction-taking

place is: -

N2H4 + O2 N2 +2H2O

The outlet temperature of water in the Dearator Tank is around

110C + 5C. From the Dearator Tank, water goes to the

economizer. In the economizer, the heat of outgoing flue gases is

used to increase the temperature of water from 105C to 235C

(approx). The water from the economizer goes to the steam drum,where Na2PO4 is added to water so as to remove the silica left (if

any) from the water. From steam drum, water through section lines

goes to the mud drum. Precipitates of Na2PO4 and silica settle

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down and are drained off from the mud drum using CBD. Water

from mud drum through sections lines goes to the furnace. In the

furnace the temperature is around 1200-1400 deg C. This steam

then goes to super heaterzone.

In this zone, there are two super heaters primary and secondary, an

temperature is connected in between the primary and secondary

super heater to control the temperature of out going steam by

spraying pressurized water droplets. The steam produced is then

connected in the header and then it is sent to the turbine section.

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2.2.Recovery boilers

The process of producing steam is same in recovery boiler as in the

coal feed boilers. The difference lies in the combustion. In

recovery boilers, the heat energy is recovered in boilers; heat

energy is recovered from the wastage. The conc. black liquor from,

evaporate section is taken and sprayed into the furnace by a nozzle

of black liquor gun. As the black liquor falls into furnace at its

ignition temp. The organic part of it i.e.-lignin burns to give heatenergy and inorganic part i.e.- sodium salts are collected as smelt

when dissolved in water is called weak white liquor or green

liquor.

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Three Element Control Loop in

The Boiler

Feed water flow

This control loop is used to control the feed water flow. The feed

water control systems, maintains the drum level at a manually set

value by using both feed forward and feed backward control. The

feed for a signal is the steam flow measurement, which

manipulates the set point of feed water flow controller and

therefore, manipulates the feed water flow to equal the rate of

steam being withdrawn from the drum. The bias of the summing

unit is such that during steady state conditions the output of the

drum level controller does not affect the set point of the feed water

flow controller. Since the liquid level process is subject to rapid

load changes and is not self-regulating, feedback must be applied

to eliminate drift. The feed back path is formed by the drum level

signal from the drum level controller. This controller trims out the

change in error during a load change or other transient variations in

drum level.

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Air Flow Control Loop

The next very important control loop is the Air Flow Control Loop.

It is required because in deficiency of air, there will not be proper

burning of coal and in case, the air is present in excess, we have the

heat loss. Thus in both cases there is an economical loss. So we

have a control loop for air also.

General Data of Boilers

1) H.P Boilers (no. 1, 2 & 3)

Steam Pressure at output-86 kg/cm2

Steam Temperature at output-490deg celc.Steam producing capacity- 35-tones/ hr

2) Recovery boilers (ABIL & JMW)

Steam pressure at output -46 kg/cm2

Steam temperature at output-400 deg celc.

Steam producing capacity - 35-tones/ hr

4. Turbine section

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There are two turbines of capacity 18 MW & 6 MW respectively

(namely TG and BTH). Both the turbines are steam driven. The TG

turbine uses steam at a pressure of 86 kg / cm2

And the BTH turbine uses the steam at the pressure of 46 kg/cm2.

Generally, 4 tones of steam is used for the production of 1 MW of

electrical energy as per approximate value. The process of

producing electricity is same in both the turbines. The rotary blade

of the turbine is set to motion by the steam pressure and hence the

shaft of the turbine, which is coupled with the generator, rotatesand produces electrical energy.

Genral Data of Turbine:-

Inlet Steam Pressure: -86Kg/cm2

Inlet Steam Temp. :-( 490 +5deg.C) or (490 5deg.C)

Steam pressure at first extraction: - 10Kg/cm2

Steam temp.at first extraction: - 270deg.C

Steam pressure at second extraction: - 3Kg/cm2

Steam temp. At second extraction: -150deg.C-170deg.C

Input RPM to gearbox: -8000

Output RPM to gearbox: -1500

For BTH Turbine: -Inlet steam Pressure: -46Kg/cm2

Inlet Steam temp: - (490 + 5deg.C) or (490-5deg.C)

Input RPM to gearbox: - 1500

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PULP MILL SECTION

Raw Materials & specifications

Paper is made of pulp and pulp is made of fibers, which is obtained

from various materials like grass, bagasse, wood & bamboo. Any

material for pulp is selected on the basis of: -

1. Ample supply

2. Available to pulp mill throughout the year.

3. High yield of quality fiber.

4. Should not deteriorate in storage.

5. Capable of being collected & stored in small area and

transported, if necessary, at low cost

6. Cost of conversion to paper must be low.

7. Cellulose fiber must be of suitable size and character.

8. Location of paper mill must be close to the location of the

raw material.

9. It must make paper of sufficient quality to be competitive in

the international market.

10. It must be cheap.

11. Must give good printability.

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The ideal fiber for high-grade paper should be high in cellulose

content and low in lignin content. The raw materials used in the

paper industry are of two types: -

1. AGRO BASED

These are the short fibers.

1. Bagasse

2. Khal

3. Khar

4. Sabai grass2. WOOD BASED

1. Bamboo

2. Eucalyptus

3.Veneer waste

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Different Views Of Paper Making Process

At Different Machines

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DRIVES

Different Drives Used In Paper Making Process And Also

In Power Generation Process

1) AC DRIVES

2) DC DRIVES

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Overview Of DC DRIVE System:-

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Chipper House

Introduction

It is necessary to reduce the wood to chips for pulp manufacture in

order that the cooking liquor may penetrate the wood quickly,

completely easy to transport pneumatically or on belt conveyers,

and to store. This operation is known as chipping and the machine

used for cutting the wood into chips is known as chipper. Thus,

chipping is a necessary operation but is also a drastic action, which

caused fiber damage and effects pulp quality. Damage is caused

when wood is subjected to compressive strain as a result of

bending, twisting or compression.

Screening Size

The size of the acceptable chips after screening varies

considerably. In sulphite process, the aim is to have an average

chip length of about 20 mm but chips are present ranging from less

than 10mm to over 35mm long. Shortening of the chip length tends

to give better impregnation of the chips, it is not suitable to

decrease the chip length too much, as a big number if the fibers

will be shortened and thus the strength pf pulp decreases. Short

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chips also mean more fines and saw dust, higher power costs in

chipping, a smaller percentage of long fibers in the pulp and

reduced pulp yield.

New Pulp Mill

Introduction

The New Pulp Mill has been set up recently to produce the

indigenous pulp for paper machines of the unit. The setup of the

mill was aimed at fulfilling the needs of paper machines numbers

4,5, and 7. New pulp mill has helped in becoming self-dependent

in terms of pulp requirement. Chief raw materials used are

eucalyptus, bamboo, wood scrap and poplar etc. The raw material

is first chipped in the chipper house with the help of two venoclain

drum type chippers, the wood/raw material is converted into small

chips of size 1 * *1/4. After chipping operation the chips are

cooked in the digesters where indirect heating of digesters is done

with the help of white liquor and black liquor mixer. After proper

cooking the cooked slurry is washed. At the brown stock we are

using four washing stages working in counter current fashion.

After adequate washing the pulp is bleached at four bleaching

section the desired brightness of the pulp is obtained without

degrading the quality of the pulp.

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Finally the pulp after cleaning operation through centri cleaners is

stored in bleached high-density towers. This final pulp can be sent

to corresponding paper machineries. Important steps in cooking or

digesters control operations.

Liquid Penetration

To ensure reaction, it is important that all the fibers in the wood get

their proper share of chemicals and heat. Now charging of liquor

starts. First of all we start white liquor pump (white liquor contains

NaOH+Na2S) and charge white liquor as per need when requiredquantity is charged, we close the respective liquor charging pump

and charge the black liquor as per the required quantity.

Digester Heating

After this, digester cooking commences. It takes place in two ways:

-

1. Direct heating

2. Indirect heating

The digesters in the NEW PULP MILL are indirectly heated.

Indirect heating involves the circulation of cooking liquor through

external heat exchangers with the aid of circulation pumps, which

draw off cooking liquor through strainers in the digester walls and

deliever, the heated cooking liquor at appropriate inlets. The

following are the advantages of the indirect cooking system: -

1.Uniformity of circulation through out the digester.

2.Uniformity of quality.

3.Increased yield.

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4. Increased pulp strength.

5.Steam saving.

For ideal cooking the following parameters should be checked:

1.Proper temperature - 165 deg. C

2.Cooking time - 90 Min (at 165 deg. C)(Total time 260 min.)

3. Pressure - 8Kg/cm2

Digester Blowing

During the blowing of the pulp and black liquor go to the blow

tank and blow condensed steam vapors to the accumulator tank

having primary and secondary condensers, which are in operationtill blow is finished. From accumulator tank condensed steam goes

to heat exchanger through fiber filter to arrest any fibers going with

the condensed vapors.

In heat exchanger warm water is pumped from warm water tank

and hot water goes to hot water tank, which is used in brown stock

washing and bleaching stages.

Brown Stock Washing

It is the process in which the dissolved organic and in organic

materials are removed from pulp by filtreation. Our objective

should be to obtain most efficient washing by using minimum

amount of water. For this purpose we have four washing stages

operating in counter current fashion.

A low consistency suspension pulp (1-2%)is spread into vat which

contains rotating drum filter vaccum created is applied to drum

which cause the slurry to thicken as the liquor filtrates through the

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surface of the drum, as drum cylinder rotates a sheet of pulp is

formed on the pulp surface which passes through spray wash zone

and then drying zone and finally it is discharged.

Consistency

Vaccum drum filter operates with 1% feed consistency and 11 14

% discharge consistency.

Bleaching

The unbleached pulp contain a large amount of lignin and some

other impurities which have been left behind after cooking and it is

essential to bleached these pulps to obtain brighter pulps without

degradation of cellulose fibers. Thus the main aim of bleaching of

pulps can be summarized as follows:

1.Removal of residual lignin left after cooking and destruction and

solubilization of coloring matters.

2.Removal of objectional dirt particles in form of five specks inpulp.

3.Retention of strength properties of the unbleached pulp.

4.To obtain greater brightness at low cost.

The following various types of chemical may be employed for the

bleaching of pulp: -

1. ClO2, Cl2

2. H2O2, Na2O2

3. So2, NaHSO34. O2

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Washing

Again washing is done to remove the liquid chlorine from the pulp.

RefinerThe pulp is refined in the refiner. We have to refine the pulp to

make short fibered.

Mixing Chest

In the mixing chest pulp is mixed with Rosin, Alum, Ranipal and

filler like Carbon black as per requirement of the paper.

Machine Chest

After mixing the pulp is transferred into machine chest where its

consistency is maintained.

The fibrous pulp from machine chest is taken into the head box; normally

the consistency pf pulp at this stage is kept 1.5 to 2 percent .now the pulp

is make to pass on through the wire pat where the considerable amount of

water is taken out of the fibers and paper web moves ahead to the press

part .At these stage web is pressed in between the press rolls to reduce the

moisture contents of fiber .The press section has two parts:

The first press

The second press.

Now the paper is taken on to the dryers for drying purpose.

After passing through predryers an intermediate stage comes known as thesize press where the sizing chemicals such as starch are added. Then after

passing through the post dryers section paper goes towards the

calendar .A calendar is to smooth and shine the paper .Now the paper is

wrapped on the drum reel .At the final stage the paper contains moisture

contents about 5-6%.

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SPECIALITY PLANT

After this the pulp is transferred to Specialty Departmentwhere required quality paper is made from this pulp.

In paper industry a raw material (pulp) is then brought into paper

plant, technically called Specialty Paper Plant. The Specialty

paper machines installed here make Executive bond, Sunlightbond and other high quality paper.

Machine No. 5: -The pulp turns into a paper of required thickness after passing

through a number of stages and number of sections: -

1. Hydra Pulper:-It is the main chamber of pulp. Here raw

material rotates with the help of rotor. Here the backwater of

process is added because it contains chemicals. If we want to

change the color or quality from superior to inferior or vice

versa, then fresh water is used.

2. Dump Chest: - The pulp comes into dump chest from hydra

pulper. Here pulp is beaten accurately.

3. Circulation Chest: - The function of this chest is to reduce

pulp into smaller particles.

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4. Stock Refinery: - It removes impurities from the pulp and

beat the pulp.

5. Mixing Chest: - The mixing and machine chest further beat

the pulp.

6. Machine Refiner: - They remove remaining dust from the

pulp.

7. Constant Level Box: - It consists of two chambers, which

give the level of the erkensater. Its level remains constant

always.

8. Open Screen: - It consists of a hollow type roller, which is

covered by an iron net having equal no. of holes. It removes

heavy dust particles.

9. Head Box: - In this we detect weight of paper. In this

fresh water, are mixed highly purified pulp and their

ratio depend upon weight of paper.

10. Wire Section: - In this the pulp moves on belt in the

form of sheet.

11. Press Section: - In this section vaccum pressure is

applied on the sheet of paper to reduce the moisture content.

12. Dryers: - Here heated steam dryers absorb almost

100% of the moisture.

13. Size Press: - In this section we smoothen the paper we

smoothen the paper with the help of roller.

14. Drum Roll: - Final Bond paper rolls over this roll.

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View Of Speciality Plant Paper Machine

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COATING PLANT

In This Plant we increase the shininess & Strength of a Paper.

Colour Kitchen:

Firstly, The coating material is made in a colour kitchen at suitable

concentration of different chemicals.This Preperation is called

Recipe and this can be made by Kaddy Mill. Chemicals Include

Starch,Latex,Calcium Carbonate & several other resins which are

imported from MALAYSIA & BRAZIL.

Coaters:

This Material goes to the three Coaters which coat this material on

a paper at three stages. At each stage we find its moisture

contents,thickness etc. by scanner.

Super Calendar:

From coater this paper reels goto Super Calendar to increase its

Shinning by continuous rolling a Reel in a cylinders.

Rewinder:

After this paper goes to Rewinder where reel is packed more

efficiently.

Lamination Machine:

If we want to make a laminated paper then we send the paper to

lamination Machine in this two reels of paper from different ends

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are joined with a help of glue which is made of starch. If we need a

paper for playing cards we put black die in glue so that we cant

see what is written on opposite side.

Now this laminated paper is dried by steam cylinders which are on

a above side of lamination Machine.

Cutters:

After this paper goes to 2 Cutters to make a sheets of proper size.

These paper reels are cut in form of sheets by pneumatic cutter

which are carrying circular knife.

Wrapmatic machine

These sheets are go to Wrapmatic machine for bundling. This is

specially designed Machine in which we have three grippers .

We feed the paper in it either automatically or manually,which are

picked by jaws like structure and through belt it pulled back where

it is picked by gripper 1,we use cylinders for each gripper.

Gripper1 forward this bundle of paper to gripper2 then gripper2

send it to gripper3 but before gripper 3 this bundle is covered by

outer cover which comes here with the help of reel this is

straighten by vaccum when bundlr reach near it ,this outer cover is

cutted by a cutter.gripper3 picked this bundle one rodless cylinder

is use to apply glue .it is pneumatic cylinder. We use brushes to

increase smoothness in gluing .Then this bundle goes under the

another glue nozzle to glue the sides.this glue is maintained on

high temperature so that our glue not solidifythis is maintained by

head & hose.this bundle move to different lifts the location of liftsis controlled by gate which in turn is controlled by cylinder.

From there we move a paper to Finishing House.

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PARAMETERS OF INSTRUMENTATION

1). Pressure

2). Temperature

3). Level

4). Flow

5). Consistency

6) . PH

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761 CONTROLLER(Bells make)

The single station controller used in BILT is the 761 series station

controller .The 761 station controllers is self contained microprocessor

based controller having the standard proportional integral and derivatives

function .The exact tuning method used in it does not use any arbitrary

process model .Instead it takes microprocessor technology. To make

controller adjustments based on the actual current process dynamics. The

controller is equipped with an RS485 serial communication port. This

controller has got all the configuration and operating parameters being

stored in a non-volatile memory .During a power failure essential

controller settings and last operating condition are saved indefinitely andno batteries are required for it.

The input signals for the controller are:

Current input:

The controller can have up to four currents inputs .the input standard

range is 4-20 ma into 240 ohm input range can changed to 1-5v dc by

changing input.

Thermocouple converter input:

One 4-20 mA measurement signal from temperature transistor or

equivalent using thermocouple is provided to

the controller.

RTD input:

It is used for one input from 100 ohm platinum RTD for direct

temperature measurement or two elements RTD for direct temperature

measurement or two elements RTD for temperature difference input.

Discrete input :

The controller can have up to two contact or transistor switch input 5V

DC nominal open circuit voltage 1mA maximum current.

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The output signal for the controller are:

Control output signal:

4-20 mA DC into 500 ohm maximum standard non isolated output.

Auxiliary Out put signal:

It can be configured to transmit the measurement, setpoint, condition

input or output 1 signal as a 1-5 V DC output signal into 2K Ohm

minimum.

Discrete input:

The controller has two non isolated open collector transistor switch output.switch reading are 50 V DC maximum and 250 mA maximum.

Transistor power :

The standard controller can provide 25 V DC nominal field power to two

4-20 mA transmitters .power supply has 250 ohm limiting resistors at

each transmitter connection.

Its operating limit in terms of temperature is 5 and 50 C. The relative

humidity limits are 5,95%.the supply voltage required is

A.C supply voltage :

110V, 220V, 50 Hz.

D.C supply voltage :

24 V ,1 mA

The resolution of the display is +-0.1% of the upper range value. The

resolution of the bar graph is 2% of upper range value.

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Segmented graphic display indicates the set point, measurement and

controller output .Each segment represents an incremental reading of 2%

of span the set point is indicated by illumination of the single segment in

the set point display. For measurement and controller output reading the

segment illuminates to form a bar graph .The desired reading is selectedby a selector key the function being displayed is identified by an

illuminated dot located above the corresponding bar graph.

The controller operates in one of the three following modes: NORMAL

,READ OR SET . In NORMAL operation the controller performs the

usual controller function READ mode the operator can read the value or

status of various control parameters . In SET mode the operator can

change these parameters and can adjust them according to theirrequirement .

The description of various keys of the controller is given below

W/P :

Depending on the configuration it permits the controller to be

used either as a workstation or panel controller.

R/L :

Depending on the configuration it permits the user to select

remote or local set point .

A/M

Depending on the configuration it permits the operator to select

automatic or manual controller.

TAG

Used to go from normal to read mode and to return from any

point in read or set mode to normal mode.

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In normal operation used to change local set point ,output etc. in read

or set mode used to change configuration settings and to sequence through

parameters categories.

ACKIn normal mode used to acknowledge an alarm condition .in read

or set mode used to step sequential through every parameter in

structure

SEL

In normal mode used to move the bar graph identifier dot .in

read or set mode returns display in minor incremental back

through program structure.

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PROGRAMMABLE LOGIC CONTROL (PLC)

The P.L.C stands for Programmable logic control .It is an industrial

computer based system which performs discrete and continuous

control function for a plant or factory automation .The first P.L.C

was designed in 1968.

Some of the points describing how a P.L.C is different from a

computer are as follows:

Real Time Operation :

The P.L.C is a real time operation system.

Environmental design :

The P.L.C is much more suitable for the environmental

conditions like heat, dust moisture electrical noise,

interference etc.

Programming language :

The programming done in P.L.C is relay logic programming

and also sometimes blocks oriented language.

Maintenance and troubleshooting :

The P.L.C has got modular design and inbuilt diagnostic

software due to which the maintenance and problem

emerging are dealt with very easily.

The various P.L.C components are as follow:

C.P.U

Power supply

I/O System

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Programming Unit

Peripheral Devices

A brief description of these elements is given below:

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C.P.U:

It stands for the central processing unit .It contains the processor

which performs all the work required to be done for the process

control .It act as the brain of the P.L.C it performs function whichare given below:

Logical operation:

It performs the logical operations like AND, OR, NOT.

Timers:

The C.P.U can also provided the functions of a timer .It can

provided on delay (the output will be produced after a certain delay

pf applying the input),off delay (the switching off occurs after a

delay of applying the switch off command .Pulse (high output

when input is high and low output when input is low)

and extended pulse (it has the same output as for the pulse but it

completes its pulse time even when the input signal goes low.

Counters:

This function of C.P.U is used to count up as well as down.

Flip-Flop:

It is used to latch the signal.

Power supply:

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It is used to charge the various units (I/O system, peripherals &

C.P.U) connected together to make a P.L.C it supplies the power at

various levels as required by the units.

I/O System:The input module is used to convert the various input signals

which are in the form of 24V DC, 220V AC, which are understood

by the C.P.U the output module does the work opposite to that of

the input module it converts the 5V DC signal given by the C.P.U

to 24 V DC 220 AC as realized by the other devices in the field.

Programming Unit:

The programming unit provide an inter face between the P.L.C and

the user during the program development start-up and trouble

shooting.

The programming of P.L.C can inform by three ways:

STL statement list

Ladder logic diagram

Control system flow

The tools need are :

Programmer

Software

The connector used for the purpose of connecting programmer &

P.L.C is RS 232 it is 9 pin used for serial communication.

Peripherals:

The peripherals include communication cards and memory. The

communication cards are used by C.P.U to send and receive the

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signal to and from various ends respectively. The memories used

are ROM and RAM. To store the application and the executives

program.

Types:

The P.L.C are of two types:

Modular

Non-Modular

The modular type of P.L.C have each and every components fitted

in such a way that it can be checked by taking it out but the nonmodular type of P.L.C have every thing fitted within & it can't be

taken out in any way .

Companies:

There is a wide variety of P.L.C available in the market but most

common trade names in P.L.C are :

Siemens

Messung

Bhartiya Cutler Hammer

Allen Bradely

Telemecanique

Cegelec

Crompton Greaves

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Factors:

The factors which are kept in mind while selecting a P.L.C:

1Number of inputs and outputs

2.Cost

3.Space available

4.Speed and scan time

How P.L.C Works

The functionality of P.LC includes the following:

Input updating

Program execution

Output updating

The functioning of the P.L.C include firstly input updating it

checks every input &updates the input value if it gas changed.

Then it executes the program feed in already and then according to

the values generated for a output it gives the output .The time taken

in performing the above three functions is called the scan time.

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DISTRIBUTED CONTROL SYSTEM (DCS)

D.C.S stands for distributed control system. It is the dominant form

of instrumentation used in industrial process control.

Features

The features of the D.C.S can be summarized as below:

1. The control system is distributed across the plant.

2. The complete plant data is integrated with the other plant and

management information system.

3. It involves high speed networks for data transmission at various

levels.

4. The D.C.S system is expanded and flexible.

5. The basic principal of distributed control system is functional

and structural integration.

Functional integration:

The term functional integration means that the same system is used

for logic, regularity, supervisory control.

Structural integration:-

The term structural integration stands means that all station from

small controllers to advent operator station for control are part of a

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system which expands step by step from small scale to wide plant

automation.

DIFFERENT COMPONENT VIEW OF DCS SYSTEM

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Components

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The various components of a distributed control system are:

Process controllers.

Operator station.

Engineering station.

Information management station.

Gateways.

Networks and protocols.

A brief description of the components is given below:

Process controllers:

These are a part of level one control. These include single loopcontrollers, multiloop controllers, P.L.C etc

Operator station:

This is a part of level two controllers it include both low and high

end man machine interface. The man machine interface equipment

includes simple panel mounted displays and push buttons

monochrome video terminal, supports of standard Guts etc.

Engineering station:

It includes the process controllers configuration it uses ladder

logic, block oriented programming language and other high level

languages support for control configuration. It uses for plant data

documentation.

Information management station :

It provides facility for process decision making bythe management.It has extensive reporting facility also.

Gateways:

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It is a part of three components. It provides a data transparency

between various networks like control network to control network,

control network to plant network.

Networks and ProtocolsThe networks are used for high speed data communication for level

one and two components. The various topologies used for

networking are:

Bus Topology

Ring Topology

Star Topology

Bus Topology

The bus topology uses CSMA principle that is carrier sense

multiple access. Direct mutual communication between two nodes

or stations is possible in this topology .These type of topology has

no master on the network. In this topology any station that needs to

transmit can be provided no other station is doing so. If two station

start simultaneously, both will stop and the higher priority station

begins after waiting a period of time.

Ring Topology

The ring topology uses token passing principle .communication

takes place from one node to other in a sequence till the required

node is reached.

Star Topology

The star topology uses central node that handles all exchange of

data .The communication is point to point between central nodeand peripheral node .It not a very popular topology.

Functional Units:

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Brief explanation of the blocks connected along with the D.C.S is:

Local control units :

The process input /output signals are connected to the local controlunits, which can be of various levels of cost and reliability .The

most critical loops, are usually placed in dedicated card controllers

rest of the control loops ate placed in unit operation controllers,

and the monitoring and alarm functions are connected to local

multiplexer. The briefings of the above mentioned devices are

given below:

Dedicated card controllers:The input /output for the most critical loops the one which should

continue functioning even if the central processor or the data

highways fails. This is the most expensive but also the most

reliable method of PID implementation in a D.C.S system. Each

D.C.S supplier offers a wide variety of card controllers having

from one to four analog output, four to twenty analog input and

two to eight digital input and outputs. There execution speed

generally ranges from four to ten executions per second . the

individual card controllers are connected to the data highway of

D.C.S. If the central processing unit of D.C.S fail or if data

highway spoils,only the communication link is lost to the card

Controllers, the control loop itself continues functioning.

Unit operation controllers:

A unit operation controller is dedicated to a unit operation of the

process, such as a chemicals or a distillation column, and therefore

all the input /output associated with that unit operation is connectedto that unit operating station. If this level of reliability is selected,

the process will remain under control as long as the unit operation

controllers are functioning, even if the central processor of the

D.C.S fails. Inversely, if the unit operation controllers fails, that

failure will interrupt the controls of only one unit operations, while

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the rest of the plant remains unaffected .Therefore the number of

loops at risk equals the number of loops servicing the particular

unit operation.

Local multiplexer:The proper local control unit choice for the type of input/output

which serves monitoring functions but not control functions is the

local multiplexer .This type of local control unit does not execute

any control functions it only transmit input/output to form the

central processor.

Data highway:

The data highway is communication device that allows adistributed control system to live up to its a name, permitting

distribution of controlling function through out large plant area.

Data highways vary in length as a function of traffic capability and

speed of transmission .Highways lengths can be in excess of 5

miles. The most popular medium is coaxial cable. Several suppliers

supply highways made of Twin ax cable, a twisted and shielded

coax. Shorter highways may be constructed of a pair of twisted and

shielded copper wires. The most recent addition is the fiber glass

cable, making of fiber optics .Fiber optics is attractive for use as adata highway because it eliminate of electromagnetic and radios

frequency interference, ground loops, and common mode voltages.

It is safe in explosive or flammable environments. et can carry

more information then can copper conductors. It is inert to most

chemicals and it is lighter and easier to handle than coaxial cable.

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Functioning of D.C.S

The solid state electronics portion of the locally mounted

equipment is a special purpose minicomputer, programmed toperform the control functions for which the distributed control

system is being used. It has an input section and an output section,

but the major portion of circuitry is made up of the central

processing unit (CPU), read only memory (ROM), random access

memory (RAM),and registers and buses that are characteristics of

microprocessor base devises .The CPU operates with a clock to

repeat a sequence of programmed subroutines over a time period

,typically half a second. This period is divided into a number of

segments of time slots, in each of which other subroutines specific

to a control operation are carried out .The subroutines ate called

algorithm they are a program of instructions designed to perform a

specific function. Depending on the configuration practices of a

particular supplier ,time slots may me of equal length ,with one

algorithm per slot ,or they have variable lengths, with a series of

algorithms used to accomplish the control action the electronic

circuitry associated with a module controlling a number if loops is

contained on several complex printed circuit cards ,frequently withthree or four layers of foil in one card .The cards are usually

plugged into a back plane containing buses that provide

communication between these.

Each time slot of this controller file has a 1/32 of a second period,

and there are 16 times slots. Accordingly, all operation are repeated

every half second .At a beginning of the half period, all the inputs

are scanned by a multiplexing circuits, and the analog signals arechanged to digital values, which are then stored in registers as

binary numbers. The transition from analog to digital is performed

by a 13 bit analog to digitals converter circuits.

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All the information about 16 time slots such as inputs & outputs

value is stored in a data base .Functional subroutines (algorithm)

are stored in ROM .When 1/32 of a second period begins, the

information for that particular time slot is brought from the database into a section of RAM. The configuration is checked to

ascertain which algorithms are to be used. An output value is

computed and sent to an output register. The updated function

information is returned to the data base, and the time period is

completed, to be followed by the next 1/32 of a second operation.

The output register in this case is one of eight (the controller file

services eight control loops).The binary value of each output ischanged in a separate conversion circuit to a frequency which is in

turn converted to a 4-20mA output signal ,updated every 1.2 s.

Some of the advantage that a distributed control system has in

comparisons to the computer systems is:

Distributed control system requires less installation cost because

less wiring is required when information is transmitted serially

across the two wires on a data highways, rather than in parallel

over many pairs of wires. Panel space is also reduced and so is the

room size required to house it. The cost of the distributed control

system is greater on a hardware basis than its equivalent analog

controller ,but the overall cost including installation is lower.

From the point of view of the operator,the interface with the

process is improved. The group display provides a means of

viewing a combination of control loops that has meaning in termsof process association.

The distributed control system can be called a computer, but it is

no longer a single mainframe. Instead, many small computers are

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distributed throughout the remote area installation, sharing the

work that the mainframe had to do alone.

The distributed control system is also flexible and relatively easy to

expand.

The programming effort required for the mainframe computer

system is also eliminated. The system programming that directs the

operation of the remote controller electronics, the central station

and the communication links is furnished as part of the distributed

control package .Furthermore, the programming required to tailor

the system to the needs of the individual process to which it is

applied can be done without knowing a high level programminglanguage.

A most common type of backup available from most of the

suppliers is in form of manual stations. These are specific to a

single control output and allow a local operator to take over from

the automatically generated signal at any time.

The availability of a system is defined as the ratio of mean time

between failures (MTBF) and mean time between failures and

mean time to repair (MTBF +MTBR).

It is clear that a system will be most available when it is very

reliable (high MTBF) and can be quickly repaired (low MTTR)

.Since distributed control equipment is highly modular and

contains many printed circuit cards, time to repair can be very short

if sufficient spare parts are available.

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INSTRUMENTS USED IN BILT

1. Conductivity measuring instruments used in D.M. Plant.

2. pH measuring instruments used in D.M. Plant .

3. Flow measuring instruments installed at PDM tank, super

heater, water inlet in steam drum and in turbine section.

4. Pressure measuring instruments installed at ID fan, FD fan,

main steam pipe, derator tank and turbine section.

5. Temperature measuring instruments used in main steam

line, derator tank, steam drum, furnaces and also in turbinesection.

6. Level measuring instruments used in various drums and

tanks used in this section.

7. Control valves are installed at different places in the whole

powerhouse.

8. Speed measurement of rotational speed of shaft in turbine

section.

9. 761 controller is used in every section of powerhouse.

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Control Valve

A control valve is a final control element in a running process.

The change in the position or condition of the control valve

varies with process parameters. In level, pressure, flow and

temperature applications control valve can control the process

according to the requirement .It consists of three parts: -

1. ACTUATOR: It is a part of control valve, which apply

the force on valve for controlling the process. It looks likepiston, which can move up and down according to the

requirement. The actuator is based upon the concept of pressure.

F = (P1 - P2) x A

Where, P1-P2= Pressure differenceA= Diaphragm area

F= Force applied

2. VALVE: It is a part of control valve, which can be operated

with the actuators manually, and an actuator operates valve. It

has many types : -

a) Butterfly valves

b) Pilot valves

c) Plug type valve

3. POSITIONER: These are fast responding precision

calibrated, force balance instrument providing accurate valve

positioning.

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Flow Measurment

Flow Measurements are also important parameters to be

measured. The flow rate of the flowing pulp gives an idea of the

consistency of the pulp. The various flow meters, which are

used in BILT, are: -

1. ROTAMETER: - It consists of a vertical tube with a tapered

cone in which a float assumes a vertical position

corresponding to each flow rate through the tube. The tube is

made up of steel and float is of brass. It works on equation: -

Qv = CEA2/Zgpd

-------

e

If Pd = Pressure is held constant then volume flow rate is

directly proportional to orifice area.

2. ORIFICE METER: - It consists of an orifice plate inserted

in a pipeline cases an increase in flow velocity and a

corresponding decrease in pressure. The Flow pattern shows

an effective decrease in cross of flow beyond the orifice plate

with the maximum velocity and minimum pressure. The plate

may be concentric, eccentric or segmented.

3. VENTURI METER: - The basic design of a venturi tube

comprises three sections viz the converging conical section at

the upstream, cylindrical throat, diverging recovery outlet cone

at the downstream. The inlet cone tapers down from the pipearea to the throat section of a smaller area to produce the

necessary increase in velocity and decrease inpressure. The

throat provides a point of the measurement of this decrease in

pressure where flow rate is steady.

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Magnetic Flow Meter

The transmitter is based upon the principle of Faradays law ofEMI according to which, when a conductor is moved in a magnetic

field, a voltage is induced in the conductor.During the

electromagnetic flow measurement, the fluid passes through a

magnetic field applied normally perpendicular to the direction of

liquid flow. The movement of liquid induces and electric voltage

which is proportional to the average field velocity and therefore to

the volume of flow.

In the case of electromagnetic flow transmitter:

U = K x B x D x V

Where, K = Instruments constant

B = Strength of magnetic field

V = Average velocity

D = Pipe diameter

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Pneumatic Current to Pressure converterThe main principle behind this type of I/P converter is that a core

is wounded by coil, which receives a standard input signal of 4-20

mA, and it converts this electrical signal into a pneumatic signal.

According to Faradays Law when a coil is carrying a current, a

strong magnetic field is produced around the coil. This magnetic

field is used to attract the soft iron core, to which is attached a

flapper and nozzle.

The nozzle opening is governed by the amount of current through

the coil. A strong signal, i.e. large current would bring the flapper

closer to the nozzle and this is provided to a pneumatic relay

which produces an output in range of 3-15 PSI which are linear

with 4-20 mA input signal. This output is capable to operate the

control valve.

I/P transmitter is also known as current to pressure converter

since it converts or transmits current signals into pressure signal.

In control loops where control valves are used I/P converter areused to operate the control valve.

The transmission of signal to current is required since controllers

in control loops are current controlled. The controlled valve open

and close according to a set point. The signal from the controller

is electrical but nature of control valve is pneumatic. So I/P

converters render the signal, which is suitable for control valve

operation.

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Temperature Measuring Instruments

(A)Thermocouple:- Thermocouple is made up of two dissimilarwires joined at their measuring and forming the measuring

junction and hot junction.

A small voltage known as sees back voltage creates at another

junction.i.e.cold junction. This voltage change in accordance withthe temperature. The controller or monitor measures the small

voltage and converts it into a temperature signal and controls the

temperature of loop and tank.

(B) Resistance Temperature Detector (RTD): - RTDs areusually platinum wire, wound on a glass or a ceramic babbin and

sealed with a coating of ceramic or glass. They can also be made

by depositing platinum as a film .The electric resistance of RTD

changes as a function of temperature.

The circuit is similar to a wheat stone bridge .A constant current

into the bridge produces an output voltage that varies with

temperature.

RTDs are generally more accurate and more stable over time than

thermocouple.

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pH meter

pH Meter :

It is a device which measures the pH of any liquid such as acid

alkalies and water.

Introduction about pH :

pH is a chemical factor which denotes the acidity or alkalinity

of a solution . The degree of acidity or alkalinity of an aqueoussolution is determined by relative concentration of hydrogen and

hydroxyl ions in that solution. When the hydrogen ion

predominates the solution is acidic and when hydroxyl ion

dominates it is alkaline .

Working of pH Meter:

Hydrogen ion concentration is measured on scale that ranges from

0-14. When the value on scale is 7.0 hydrogen ions and hydroxyl

ions balance each other as in case of distilled water.

When the pH value is more than 7.0 solution is alkaline and when

the value is less than 7.0 the solution is acidic.

The measurement is done by immersing a cell (pair of electrodes)into the solution to be measured and measuring the voltage

developed across them .In the pH cell one of the electrode is

reference electrode is at a potential regardless of the pH value of

solution under test. The potential of the other electrode called

measuring electrode is determined by pH value of solution. Thus

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the potential difference between the two electrodes depend upon

the pH value of the solution.

Now a days combination electrode is used thus eliminating the

need of two electrodes .The combnation electrode is a delicatechemical transducer to be handled very carefully .The pH

combination electrode generates the potential difference which is a

function of the pH value of the solution being tested. This is

amplified and calibrated and fed to digital voltmeter which is again

suitably calibrated to read directly in pH.

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Differential Pressure Transmitter

Pressure Measurement:

The differential transmitter may be used for measuring liquid flow,

level or other applications requiring accurate measurement of

differential .The quality of measurement depends to a great extent

on proper installation of the transmitter.

Construction of Differential Pressure Transmitter

A pressure transmitter consists of sensor element two metal pieces

are separated by sensor element seal as a diaphragm .It has two

states low and high oil is filled in it and this system is covered with

an insulator. When we apply the pressure on its low or high side

then the pressure flows through the middle diaphragm and the

middle diaphragm offers capacitance effect due to two plates

separated by an insulator.

In this system insulator is diaphragm and conductive surface is the

metal piece when oil is linked with the diaphragm.

When pressure is applied then capacitance C2 increases and C1

decreases .It flows from high level than voltage will be developed

across to terminals, which is differential pressure, so it called as

differential pressure transmitter.

The pressure transmitter has a variable capacitance-sensing

element the - cell. The differential capacitance between the

sensing diaphragm and capacitor plate is converted electronically

to a two wire 4 20 mA DC signal.

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P = K1 x C1 - C2

-------------C1 + C2

P = Process pressure

K1 = Constant

C1 = Capacitance b/w high pressure side and sensing diaphragm

C2 = Capacitance b/w low pressure side and sensing diaphragm

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Liquid Level Measurement

Differential pressure transmitter used for liquid level application

measures hydrostatic pressure.

The pressure is equal to liquid height above the tab multiplied by

the specific gravity of the liquid. Pressure depends upon volume or

vessel shape.

Open Vessel:

A pressure transmitter mounted near a tank bottom measure thepressure of liquid above. Make connections of the high-pressure

side of the transmitter went the low.

Closed Vessel (Wet Leg Condition):

Pressure above a fluid affects the pressure measure at the bottom of

a closed vessel.

The liquid specific gravity multiplied by the liquid height plus the

vessel pressure equals to the pressure at bottom of the vessel.

To measure true level the vessel pressure must be subtracted from

the vessel bottom pressure. To do this, make pressure tab at the top

of the vessel and connect this to the low side of a differential

pressure transmitter.

Vessel pressure is equally applied to both the high and low side of

transmitter. The resulting differential pressure is directly

proportional to liquid height multiplied by liquid specific gravity.

I/P Transmitter

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Current to pressure transmitter accepts the electrical inputs signals

and converts it into proportional pneumatic output. Typically 4 to

20 Ma is converted to 3 to 15 pounds per square inch (Psi).the most

common application of this transmitter is to receive electrical

signal from a controller and to produce a pneumatic output foroperating a control valve positioner .

It has a solid state pressure sensor that moniters the output

pressure and is a part of electronic feedback network.

The final assembly of a transmitter contains the electronic circuit

board, pilot/actuator assembly and booster stage.

Electronic circuitThe input current signal is received by electronic circuit and

compared to the output pressure from booster stage .a solid state

pressure sensor used strain gauge this film technology. It can

withstand loops of pressure w/o damage.

7

Mag actuator Pilot stage Booster Valve

Solid state press sensor

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Magnetic actuatorThe electronic circuit control the level of current flowing through

the actuator coil which is located in the pilot /actuator assembly. A

change to the level of coil current is to made by electronic circuitwhen it senses a discrepancy between the pressure measured by the

sensor and pressure required by the input signal. The actuator

performs the task of converting electrical energy to motion.

Pilot stageIt contains two opposed fixed nozzle. It also contains the deflector

which is moving element. The supply nozzle is connected to the

supply air stream. The receiver nozzle captures the air stream andconverts it back to pressure . the receiver nozzle pressure is the

output pressure of the pilot stage. In order to vary the pilot output

pressure the velocity stream is diverted away from the receiver

nozzle. This accomplished by the deflector which is cylindrical

aerodynamic body located between the two nozzle.

In response to a change in actuator coil current, the deflector is

repositioned between the nozzle. There is a linear relationship

between the coil current and the pilot stage output pressure . thepower of f or fail safe , the position of the top of the deflector is

near to the centre of stream and results in zero pilot output

pressure. As the coil is energized , the deflector is drawn out of the

stream. maximum pilot output pressure results when the deflector

has moved completely out of the stream.

The deflector material is tungsten carbide and nozzle are 316

stainless steel. The nozzle has a large bore of 0.016 inches whichprovides good resistance to plugging.

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Booster stageThe receiver nozzle pressure controls the booster stage which has a

poppet valve design. An increase in the transducer output signal.

A decrease in the receiver nozzle pressure positions the valving inthe booster stage to allow the exhaust to occur, decreasing the

output signal.

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CONCLUSIONIt can be concluded that BILT is a modernized and well-equipped

industry form every aspect whether it is manufacturing process or

finishing process. During my training period, I got valuable

knowledge regarding the most modern techniques used in

Electronics & Instrumentation trade that is P.L.C & D.C.S .My

training also made me familiar with many machines & instruments

used in industry. The management & employees are very helpful. I

hope that the valuable knowledge I have gain here will help me infuture.

Electrical Training Report

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Transcript of Electrical Training Report