Project Report Spd

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CONTENTS

Topic Page No.

Acknowledgment2

1. Company Profile 3

2. Introduction to CRD 6

3. Operation of the various units

a. Coil build up line 6

b. Bell Annealing line 9

c. Rolling Mill 12

d. Pull through furnace 17

e. Pickling line 21

f. Slitting line 25

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ACKNOWLEDGMENT

I am very thankful to the management of JINDALSTAINLESS LIMITED, who allow me to complete my training intheir esteemed concern.

I am also very grateful to Mr. V.P. Gupta who guided

me at every step of my training in the COLD ROLLING DIVISION(CRD), a unit of JSL.

I am specially thankful to Mr. Rahul Wadia , Mr.Tilak Raj & the staff members of blade steel (MechanicalDepartment) for their co-operation in my training period & their helpin the completion of this training report.

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COMPANY PROFILE

Jindal Steel and Power Limited (JSPL) is one of Indias majorsteel producers with a significant presence in sectors likeMining, Power Generation and Infrastructure.

With an annual turnover of over US$2.9 billion, JSPL is a part of the aboutUS $ 15 billion diversified O. P. JindalGroup and is consistently tapping newopportunities by increasing productioncapacity, diversifying investments, andleveraging its core capabilities to

venture into new businesses. The company has committedinvestments exceeding US$ 30 billion in the future and hasseveral business initiatives running simultaneously acrosscontinents.Mr. Naveen Jindal, the youngest son of the legendary late Shri.O. P. Jindal spearheads JSPL and its group companies. Thecompany produces economical and efficient steel and powerthrough backward integration from its captive coal and iron-ore

mines.From the widest flat products to a whole range of long products,JSPL today sports a product portfolio that caters to varied needsin the steel market. The company also has the distinction ofproducing the worlds longest 121 metre rails and introducinglarge size parallel flange beams in India.JSPL operates the largest coal - based sponge iron plant in theworld and has an installed capacity of 3 MTPA of steel at

Raigarh in Chhattisgarh. With a 0.6 MTPA wire rod mill and aone million tone capacity bar mill at Patratu, Jharkhand and aone million tone capacity bar mill, Jharkhand and a medium andlight structural mill at Raigarh, Chhattisgarh, JSPL will shortly becommissioning a plate mill to produce upto 5.00 metre wideplates at Angul, Odisha. The company aims for a fast-pacedgrowth so as to contribute substantially to Indias long termprosperity.

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An enterprising spirit and the ability to discern future trendshave been the driving force behind the companys remarkablegrowth story. The company has scaled new heights with thecombined force of innovation, adaptation of new technology andthe collective skills of its 15,000 strong, committed workforce.And the recognition it has received only further lends credenceto this. JSPL has recently been rated as the second highestvalue creator in the world by Boston Consulting Group; 11thfastest growing company in India by BusinessWorld; included inone of the Fab 50 Companies by Forbes Asia, 2009 and 2010;one of the Best Blue Chip companies as well as the HighestWealth Creator by the Dalal Street Journal. It has also beenranked fourth as per Total Income in the Iron and Steel sector

by Dun & Bradstreet.JSPL endeavors to strengthen Indias industrial base by aidinginfrastructural development, through sustainable developmentapproaches and inclusive growth. The company deploys itsresources to improve infrastructure, education, health, water,sanitation, environment etc. in the areas it operates in. Thecompany has won several awards for its innovative businesspractices.

As JSPL contributes to Indias growth, it has also set in place aglobal expansion plan in order to become one of the mostprestigious and dynamic business groups in the World. Thecompany continues to capitalize on opportunities in high growthmarkets, expanding its core areas and diversifying into newbusinesses. The future is studded with challenges and JSPL istaking them on with vigor and courage.With the development rights for 20 billion tonne of El Mutun Iron

Ore Reserves in Bolivia, JSPL plans to invest US$ 2.1 billion inthe next few years on mining and on setting up an integrated 1.7MTPA Steel Plant, 6 MTPA Sponge Iron plant, 10 MTPA IronOre Pellet Plant and 450 MW power plant in the South Americannation.The company has already secured land to start the project andexpects to start exporting iron ore this year. Commercialdispatch of iron ore is also likely to commence soon in Bolivia.The company will start construction on the DRI, pelletisation and

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steel project. These are expected to become operational in thenext 3-4 years.Through its 100% subsidiary Jindal Steel & Power (Mauritius)Ltd., Mauritius (JSPLM), JSPL has acquired Shadeed Iron &Steel Co. LLC (Shadeed) in Oman. Jindal Shadeed has installeda 1.5 MTPA gas-based Hot Briquetted Iron (HBI) plant with aninvestment of US$ 500 million and started commercialproduction from the Oman plant five months ahead of schedulein December last year. The company will be setting up a steelplant and rolling steel mills in Oman in the next two years.With coal reserves in Indonesia, JSPL has mines strewn acrossAustralia and Africa. The company is also engaged in themining of diamonds in the Democratic Republic of Congo in

addition to exploration of the precious stone in the states ofChhattisgarh & Jharkhand in India.

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INTRODUCTION TO

THE COLD

ROLLING DIVISION

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COLD ROLLING DIVISION

Cold Rolling Division, normally known as CRD is aunit of the Jindal Strips Limited. In this unit the stainless steel isrolled to get the required thickness of the Stainless steel coil. Thenormal output thickness of the coil is either 1.1mm or 0.45mm(known as blade steel).

The CRD is divided in the three parts which are

> CRD1 (normally known as Swastik).> SPD (normally known as blade steel).>CRD2

CRD1is used to give an output of 1.1mm thick stripused for the manufacturing of the utensils mainly. The main units ofthe CRD1 are as follows: Coil build up line Pickling line

Shot blasting line Annealing line Slitting line 20-Hi mill 4-Hi mill Annealing pickling continuous line

The output of SPD is the blade steel having athickness of 0.45mm. It is normally used for the fabrication of theblades. The main units of the SPD are as under:

Bell annealing furnace (hydrogen, LPG & LDO) Pickling and shot blasting line blade steel unit consist of

> 4-Hi roughing mills 1&2> 4-Hi finishing mill> 2-Hi skin pass mill

> 20-Hi mill

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> Pull through furnace 1, 2, 3&4> Bright annealing line 1&2> New bright annealing line (EBNER)> Slitting line 1, 2, 3, 4&5>Strip grinding line>Inspection line

The sequence of operation in the SPD is shown in theblock diagram. The sequence is as follows1. Bell annealing2. Roughing mill (Rough rolling)3. Pull through furnace4. Pickling

5. Slitting6. 20 Hi/4 Hi mill7. Dispatch

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BELL ANNEALING

The coil when comes in the CRD it is too hard to berolled. For the rolling it is necessary to soften the coil. The coil can be

softened by passing it through the high temperature for a specific timeperiod.

The bell annealing is used for the same purpose i.e. tosoft the coil & it eligible for the rolling. In the B/A 6 coils can beannealed simultaneously thus saving the time.

There are two types of the furnaces used in the unit.Both are divided on the basis of the capacity they have. The capacity

of these furnaces are 12 tones & 18 tones. The coil weight isapproximately 1 tone. So for the optimum use of the furnace the coilsare joined together to form a big coil.

In a bell annealing furnace there are three main partswhich are described below:-

1. Base Assembly:-

The base assembly is the main part of the furnace. Onthe assembly the coils are placed on each other. In this there is a fan ;called base fan used in the base of the furnace , circulates the nitrogenin the furnace. The use of N2 is recommended for getting the goodoutput & removing the oxygen from the inner side.

In this there are some diffusion plates which

separates the coils from each other for getting the even heat by thecoils. There are the inlet & outlet valves in the base for the LDO (fuel)& N2. The water is also used in the furnace to avoid the seal frombeing damaged by the heat. This seal avoids the circulation of the airfrom inside to outside.

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2.Inner Pot:-

The function of inner pot is just like a vacuum coverwhich doesnt allow the circulation of the air from inside to outside.The inner pot has 6 bolts , which tights the pot & allow it to act asvacuum cover. There are thus 3 pair of the bolts. One caution that isnecessary to be followed is that a pair of the bolts should be tighten ata time.

3. Furnace:-

The furnace is the outermost cover of the unit. All the

electrical panels of the unit are kept on the this cover. Like the innerpot it is also air tight. The temperature for the furnace is kept highestamong the three temperatures. These temperatures are> Material temperature> Process temperature> Furnace temperature

The temperature cycle of the material is as shown in

the figure. It is cleared from the figure that there are three main statesof the material as described below:-

A> Recovery

At the 850o C the stress & strain which remain in thecoil are terminated from the coil. The coil is kept at this temperaturefor 10 or 12 hours for the furnaces of capacity 12 & 18 tonesrespectively.

B> Recrystalisation

The recrystalisation is done at 720oC. The furnace is

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allowed to cool down naturally from 850 to 720oC. In this Granniesare allowed to come close which were loosen in the recovery. Thisstate remains for about 16 & 20 hours for the 12 & 18 tones furnacesrespectively.

C> Grain Growth:-

In this state of operation the grains are allowed tocombine to form a bigger grain. This process is done at a temperatureof 600oC. The furnace is allowed to cool naturally at @10oC/hour.This type of cooling is the most important cooling as the properties ofthe steel are decided by this cooling. The process is adopted for 4hours in each type of furnace.

After that the furnace is allowed to cool down at atemperature of 550oC. The coils are kept in this region for a timeperiod of 1 hour approximately. After passing through this state thefurnace is allowed to cool down at a temperature of 150 oC & then thecoils are unloaded

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ROLLING

MILL

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ROLLING MILL

In the blade steel there are 7 rolling mills for differentrolling conditions. They are:-

> 4-Hi roughing mill ............. 2> 4- Hi finishing mill ............. 3> 20- Hi mill ............. 2> Skin pass Mill . 1

The coil after the shot blasting unit comes to theroughing mill. It comes to the finishing mill after passing through thePTF (Pull Through Furnace) , pickling & slitting.

The operation of all the rolling mill is same. They

differ only in the output. The construction is almost same for all themills except the difference in the construction of the main stand.

Figure shows the line diagram for the 4-Hi finishingmill. From the diagram its all the parts & the sequence of theoperation is clear. The main parts of the mill are as under:-

1.Pay Off Reel:-

The pay off reel is also known as the uncoiler. Thecoil on the recoiler is loaded by means of a coiler car. The POR actsas a supply reel for the mill. The uncoiler is used in the first pass only& then the strip is shifted to the coilers.

2. Coiler Car:-

It is a hydraulically operated unit which is used toload & unload the strip from the coiler. The car can move up-down &reverse-forward from its position. The coil is loaded on the car & thenthe center of the coil is aligned with the mandrel of the coiler/POR sothat the coil is loaded on the coiler.

3.Snubber Pad:-

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The snubber pad is used to press the coil end so thatit doesnt jump dangerously to harm someone. It is used on the topedge of the coil & is hydraulically operated. The pressure on the coilby the snubber pad is very low & its position on the coil is just abovethe coil edge.

4.Peeler Table:-

The peeler table is of many types. Some of them ishydraulically operated which can move up & down , some haveblades which also cuts the binding of the coil & some are of fixedtype etc. etc. The main function of the peeler table is to takethe coil end to the pinch roll & leveler unit. It is also used to support

the coil mechanically & avoids it from being damaged.

5.Hold Down Roll:-

The function of the hold down roll is to hold downthe strip. It also removes the unevenness of the strip to a little degree.This roll is fixed on its position. Its size depends on the size of thestrip being rolled on the mill.

6. Guide Roll , Pinch Roll & Leveler Unit:-

The function of the guide roll is to direct the strip in astraight direction. The guide roll is adjustable according to the widthof the strip. It almost remains fixed as the width of the coil is almostfixed.

The function of the pinch roll as described earlier isto pull the coil from pay off reel & supply it to the coming unit so thatthe power consumption is lower.

The leveler on the other hand terminates theunevenness of the coil & thus a flat coil moving in a straight directionis available for the rolling. The leveler has three rolls.

7. Main Stand:-

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The main stand is the main unit of the rolling mill.This performs the job of the rolling. In this there are 4 & 20 rolls forthe 4-Hi & 20-Hi rolling mill respectively. The placement of the rollsin the main stand is shown in the figures. Figure 1 & 2 shows themain stand for the 4-Hi & 20-Hi rolling mills. The rolling force isapplied on the rolls by the screw down system. The force in the kg ismeasured by the load cells.

There are two types of the rolls in the 4-Hi mainstand which are :-> Backup Rolls> Work Rolls

The coil in the main stand passes between the work

rolls & the force is applied on the backup rolls.

The quality of output of the mill is decided by thequality of the rolls used in the mill. The quality order of the rolls ofthe each type of the mill is as under:

> 20-Hi mill ......... The Best> 4-Hi mill ......... Better > 4-Hi R/M ......... Good

Thus it is clear that the quality of the 20-Hi mill isbest among all the remaining mills. This is the only difference in theconstruction of the each type mill.8.Deflector Rolls:-

There are two deflector rolls in the rolling mill. Eachof them is used at a position covering the main stand from bothdirection as cleared from the operational diagram. The deflector roll isused for the following purposes:-A> To support the coil mechanically which doesnt allow the coil toget broken & the wrapping is better.B> To measure the line speed. The techogenerators are attached to theroll which indicate the line speed. The roll is rolled by the coil andhence the line speed is calculated from the techo`s signal.

9.Exit & Entry Coiler:-

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There are two coilers in a rolling mill one is knownas the entry coiler (ETR) & other is known as the exit coiler (DTR).They move the coil in to & fro direction in the main stand for therolling. The coilers are only used for giving the tension to the coil.

The coil is wrapped on the DTI first from the mainstand & the end of the coil from POR is caught by the ETR. Now thecoil starts wrapping on the ETR. After wrapping on the ETR the coilstarts rewrapping on the DTI. This process continues until therequired thickness of the coil is obtained.

The rolling force on the coil is increased per pass.The final wrapping of the coil is done on the DTI. The direction of the

coil movement is governed by the main stand.

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PULLTHROUGH

FURNACE

PULL THROUGH FURNACE

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The coil after the rolling at roughing mill comes tothe Pull Through Furnace (PTF) for the annealing. The PTF has manytemperature zones as per requirements. In the CRD2 there are twoPTF`s. PTF1 uses 7 temperature zones while PTF2 uses 5 temperaturezones. Each zone has a temperature controller which controls thetemperature of the zone.

Figure shows the block diagram of the PTF. Themain parts of the Pull Through Furnace are as under:-

1.Pay Off Reel:-

As usual a pay off reel is used for the supply of coilto the various parts of the unit. It is also known as the uncoiler. Theuncoiler can be expanded or compacted as per requirements ofloading the coil.

2.Deflector Rolls:-

There are two deflector rolls in the PTF like the

rolling mill. Each of them is used at a position after the POR & beforethe recoiler as cleared from the block diagram. The deflector roll isused for the following two purposes:-A> To support the coil mechanically which doesnt allow the coil toget broken & the wrapping is better.B> To measure the line speed. The techogenerators are attached to theroll which indicate the line speed. The roll is rolled by the coil andhence the line speed is calculated from the techo`s signal.

3. Guide Roll:-

The main function of the guide roll is to guide the

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coil in a straight direction. The coil after passing through the guideroll comes to the furnace via pinch roll. The guide roll may beadjusted according to the width of the coil.

4. Furnace:-

The furnace of the unit is divided into manytemperature zones. In the blade steel the two furnaces are divided intothe 7 & 5 temperature zones. The temperature of each zone in thefurnace is kept 720oC.

Before starting the operation of the PTF the nitrogenis purged into the furnace & flame is burnt on both sides of the

furnace for removing the oxygen from the furnace.

The coil in the furnace comes continuously. The coilsare welded one by one on the entry of the furnace. If the coil is brokenthen the coil is wrapped on both coilers & a rod is inserted in thefurnace. The coil at the entry of the furnace is welded with the coil &the rod is pulled towards the recoiler. The similar process is adoptedwhen inserting a new coil in the furnace.

5. Cooling:-

The coil when comes out of furnace it is necessary tolower down the temperature of the coil. For this purpose both types ofcooling i.e. natural as well as water cooling, are used. The coil iscooled naturally first & then it is passed through a cool water jacket .

6. Guide Roll & Deflector Roll:-

The function of the guide roll ,as discussed above , isto guide the coil in a straight direction so that the wrapping of the coilis good. The deflector roll on the other hand are used to serve the twopurposes. Firstly to support the coil mechanically sothat it does notget break. Secondly techogenerators are attatched to the coil for themeasurement of line speed.

7. Recoiler:-

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The recoiler wraps the coil on it through deflectorroll. The recoiler is the final stage of the PTF. The coil which iswelded atthe ends ; is cut by the hacksaw.

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PICKLING

LINE

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PICKLING LINE

Pickling is also known as the chemical cleaningbecause it uses the chemicals for the cleaning of the coil. The most

frequently used chemicals are the acids. The two main acids used are1. HNO32. HF

The acids are the most effective chemicals for thebetter cleaning of such hard materials. The ratio of the acids is 20:1for the HNO3 & HF.

Figure shows the block diagram for the pickling line.

The main parts of the line are as under:-

1. Uncoiler:-

The main function of the uncoiler is to pay off thecoil. This coil is supplied to the various parts of the line. The coil ispulled by the unit itself.

2. Guide Roll & Pinch Roll:-

The guide roll guides the coil in a straight direction.They are used between the two consecutive tanks for the betterrolling.

The function of the pinch roll is to pull the coil fromthe POR for the rest of the unit. The pinch roll is fixed on its position.The guide roll on the other hand can be adjusted according to thewidth of the coil.

3. Acid Tank:-

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There are two acid tanks used in the pickling line.They play a major roll in the cleansing of the coil. They contains acidin themselves.

The ratio of the acids is 20:1 for the HNO3 & HF. Theacids remove all the unwanted particles from the coil. Theconcentration of the acids in both of the tanks is different. First acidictank has higher concentration for the acid as compared to the secondone. The second tank has more water than the first one.

4. Brush Assembly:-

The brush assembly is consist of a roll containing

brushes on itself. The brushes are consist of hard plastic. When thecoil enters in the consecutive tank the brushes clean the coil with thewater. The quantity of the water varies according to the concentrationof the acid. For the collection of the water a small tank is providedunder the brushes.

The water continuously falls on the brushes for thebetter cleaning of the coil. The brush assembly is placed between the

two consecutive tanks as shown in the block diagram.

5. Water Tank:-

The coil after passing through acid tank enters intothe water tank. Like the acid tank there are two water tanks. One tankcontains the calcium carbonate (Lime) & the other contains the hotwater.

The lime along with the water removes the contentsof the acid from the coil. The hot water in the other tank removes thecontents of the lime & thus gives the well cleaned coil as an output.The only impurity contained is the water drops on the coil.

6. Furnace:-

The furnace in the pickling line removes the water

contents from the coil. In the furnace a temperature of 120oC is

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maintained which is sufficient to evaporate the water contents fromthe coil. The coil is now ready for the rolling at 20-Hi or 4- Hi rollingmill as per requirements.

7.Deflector Roll:-

The deflector roll used in the pickling also performsthe same job as he does in the rolling mill. The jobs are to support thecoil mechanically for better wrapping & other one is to enable thedrive to measure line speed by coupling a techo with the roll.

8.Recoiler:-

The recoiler in the pickling line perform the only jobof wrapping the coil coming from the deflector roll. The coil isremoved by shrinking the coiler from its normal position & vice-versa. The coil after the pickling goes to the slitting mill for theremoval of unwanted edges of the coil.

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SLITTINGLINE

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SLITTING LINE

The slitting line is used to cut the uneven ends of thecoil & giving the required width of the coil. The slitting line is a very

important part for the steel or any other such type of the industry.

The basic working of the slitting line is cleared fromthe block diagram shown in the figure. The main parts of the line areas follow:-

1. Pay Off Reel:-

The function of the Pay Off Reel is to pay off the coil

wrapped on it. The reel can either be expanded or compacted as perrequirements. The coil is loaded in this part before starting theoperation of the mill. The rest of the parts of the mill are supplied withthe coil by the pay off reel.

2. Guide Roll , Pinch Roll & Leveler Assembly:-

The function of this unit is to give an output in the

form of even coil moving in a straight line. The leveler is used to omitthe unevenness of the coil. The guide roll is used to direct the coil in astraight direction to the slitting blades. The pinch roll is used forpulling the coil in the forthcoming parts of the unit

3.Slitting Blades:-

The slitting blades are the most important part of theslitting mill. These blades are adjustable according to the widthrequired. The gap between the blades is adjusted by putting thespacers between them. The spacers are consist of the hard plastic orrubber. The spacers of different widths are used.

4.Scrap Winders:-

There are two scrap winders in a slitting line. When

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the required width of the coil is obtained , there remains some scrap ofthe two extremes. This scrap is necessary to be wrapped on somesuitable winder. Scrap winders are used for the winding of the scrapson themselves. The are separately operated by the two motors.

5. Guide Roll , Pinch Roll & Leveler Unit:-

The function of this unit is to give an output in theform of even coil moving in a straight line. The leveler is used to omitthe unevenness of the coil. The guide roll is used to direct the coil in astraight direction to the recoiler. The pinch roll pinches the coil for thegood wrapping of the coil in the form of a coil. This roll pulls the coilfrom the passed parts to the coming parts.

6.Recoiler:-

The function of the recoiler is to recoil the slittedcoil. The coils are separately recoiled if they are two or more than twoin number. There is a hydraulically operated arm placed over therecoiler which allow the coil to wind in a good shape.

The coil after slitting goes on the rolling mill forgetting the required thickness of the coil.

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