RSP Report

7/30/2019 RSP Report

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A REPORT

ON

OPTIMIZATION OF SECONDARY COOLING IN THE SLAB CASTING

PROCESS IN THE CCM, SMS-II, ROURKELA STEEL PLANT

BY

Shamick Lahiri 2007A1PS468G B.E. Chemical

Swastik Mohapatra 2007B5A8567G M.Sc.Phy/B.E. Electronics & Instru.

Shrey Jain 2007A4PS188G B.E. Mechanical

Rohit Mittal 2007A1PS281G B.E. Chemical

Varun Goel 2007B3A4447G M.Sc. Economics/B.E. Mechanical

Abhijeet Anand 2007B1A8481G M.Sc.Bio/B.E. Electronics & Instru.

Prepared in partial fulfillment of the

Practice School-I

At

Continuous Casting Mill, SMS-II

Rourkela Steel Plant, Rourkela

A Practice School-I Station of

BIRLA INSTITUTE OF TECHNOLOGY AND SCIENCE, PILANI

GOA CAMPUS

(May-July, 2009)


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CERTIFICATE

Thisis to certify that the project work titledOPTIMIZATION OF SECONDARY

COOLING IN THE SLAB CASTING PROCESS IN THE CCM, SMS-II, ROURKELA STEEL

PLANT has been prepared by Swastik Mohapatra, Shamick Lahiri, Shrey Jain, Rohit

Mittal, Varun Goel, Abhijeet Anand students of BITS PILANI Goa Campus. In preparing

this report under my guidance they have put in their best possible efforts.

I wish them all success in life.

Mr. Srikant Panda

Senior Manager,

SMS-II,

Rourkela Steel Plant


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ACKNOWLEDGEMENT

An activity can be termed as an accomplishment only when the purpose of it is achieved.

Every activity in life has a commencement, a progression and finally a culmination. All the

three steps require relentless effort, unflinching motivation and unvarying support.

It is our privilege to express our heartfelt gratitude and regards to Mr. Arabinda Mishra,

Assistant General Manager, HRDC for his valuable suggestions and guidance. We would liketo express our sincere indebtedness to our mentor and instructor Mr. Rajendra Kumar Roul

who has helped us in every possible way in our endeavours towards the completion of our

report. We express our sincere thanks to Mr. Srikant Panda, Senior Manager (SMS-II) and

Mr. P.P.K Patra who have been very kind enough to take some time out of their busy

schedule and guide us in our project. We would also like to express our gratitude to all the

authors of the books and the websites we have used as our reference. Last but not the least

we would like to thank each and every one who has been instrumental in the successful

compilation and presentation of this report.


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Contents

Subject Page No.

1. Abstract 5

2. About S.A.I.L 6

3. About R.S.P 8

4. Introduction 9

5. Continuous Caster: Brief Layout 10

6. Step by step sequence of slab casting in CCM SMS-II, RSP 12

7.

Relevant Formulas Applicable In The CCM 17

8. Initial Shell Formation And Oscillation Effect 18

9. Nozzle Characterestics 19

10.

Simulation of Casting Process 21

11.Conclusion 23

12.Appendix 1 24

13.

Appendix 2 25

14.References 26


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ABSTRACT

A continuous casting mill is an integral part of any integrated modern steel plant in the

world. The continuous casting process is a highly sophisticated process aimed at

improvement of energy and time efficiency of steel making thus making it a much more

economical process compared to the earlier ingot casting process.

Here in Rourkela Steel Plant, SMS-II we have made a sincere effort to study the continuous

casting process in the CCM. Our aim of the study is to understand the various intricacies of

the casting process carried out especially the secondary cooling mechanism of the concast.

We have tried to put in as much available data about the CCM and tried to simulate it and

take it as closer as possible to the ideal conditions, thereby optimizing the process.


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About SAIL

SAIL traces its origin to the formative years of an emerging nation - India. After

independence the builders of modern India worked with a vision - to lay the infrastructure

for rapid industrialisaton of the country. The steel sector was to propel the economic

growth. Hindustan Steel Private Limited was set up on January 19, 1954. The President of

India held the shares of the company on behalf of the people of India.

Hindustan Steel (HSL) was initially designed to manage only one plant that was coming up at

Rourkela. For Bhilai and Durgapur Steel Plants, the preliminary work was done by the Iron

and Steel Ministry. From April 1957, the supervision and control of these two steel plantswere also transferred to Hindustan Steel. The registered office was originally in New Delhi.

It moved to Calcutta in July 1956 and ultimately to Ranchi in December 1959.

A new steel company, Bokaro Steel Limited, was incorporated in January 1964 to construct

and operate the steel plant at Bokaro. The 1 MT phases of Bhilai and Rourkela Steel Plants

were completed by the end of December 1961. The 1 MT phase of Durgapur Steel Plant was

completed in January 1962 after commissioning of the Wheel and Axle plant. The crude

steel production of HSL went up from .158 MT (1959-60) to 1.6 MT. The second phase of

Bhilai Steel Plant was completed in September 1967 after commissioning of the Wire Rod

Mill. The last unit of the 1.8 MT phase of Rourkela - the Tandem Mill - was commissioned in

February 1968, and the 1.6 MT stage of Durgapur Steel Plant was completed in August 1969

after commissioning of the Furnace in SMS. Thus, with the completion of the 2.5 MT stage

at Bhilai, 1.8 MT at Rourkela and 1.6 MT at Durgapur, the total crude steel production

capacity of HSL was raised to 3.7 MT in 1968-69 and subsequently to 4MT in 1972-73.

In the year 1973 HSL was renamed as SAIL (Steel Authority of India Limited). Today it is the

flagship steel making company in India and one of the top ten public sector companies in

terms of turnover. SAIL is the largest producer of iron ore in India. The steel products

manufactured by SAIL include:


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Hot and cold rolled sheets and coils

Galvanized sheets

Electrical sheets

Railway products

Plates, bars and rods

Stainless steel and other alloy steels


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Rourkela Steel Plant

The Govt. of India under the ablest leadership of the then Prime Minister Pt. Jawaharlal

Nehru, decided to set up large Steel Plants by the Govt. itself after the general election of

1952. Rourkela and its adjacent areas are rich in iron ores, manganese, dolomite and

limestones, the basic materials for production of iron and steel. Considering Rourkela to be

best place for a steel plant, the survey work was completed in the year 1954. The

infrastructure work of the plant was accomplished in between 1955 and 1960. The Republic

of Germany extended technical knows how for the construction of the steel plant and the

plant was considered a joint venture of the Govts. of India and Germany. The initialproduction limit of one million tonne steel per annum was raised to 1.8 million tonne in the

subsequent years. The internationally reputed firms like the Krupp, Demag, G.H.H. Sag,

Scholomen, Cemens and Voest Alpine etc. supplied different machines and machinery parts

to the plant at the beginning stage. The Rourkela Steel Plant took the part of leadership in

the process of steel production under L.D. techniques. It could also establish itself as one of

the premier industries of the world under the system of basic oxygen converter.

Special Features

1. 1st Public Sector integrated Steel plant to be set up in the country.

2. Exclusively producing flat products.

3. First Plant in India to adopt L.D. Process of Steel making.

4. It has got an electrical sheet mill capable of producing both Dynamo and Transformergrade electrical sheet.

5. It has a special plate plant where special alloy Steel Plates are shaped to different

shapes as per requirement in the defence sector.

6. RSP has the distinction of being the unique Steel Plant in India with an integrated

Fertilizer Complex.

7. It has two captive power plants (CPP) with a generation capacity of around 120 mw.


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INTRODUCTION

Steel Melting Shop, popularly known as the SMS is one of the most important part of any

integrated steel plant. It is this place where the hot metal obtained from the blast furnace is

converted into steel with desired compositions and properties. The hot metal is melted

here and the impurities are removed by the process of oxidization (reverse of blast furnace

where reduction is the main process). After removal of impurities desired amounts of other

substances viz. carbon, chromium, nickel, silicon, molybdenum, tungsten etc. are added as

per the customer requirements. After the processing and the molten metal is solidified

using various processes and then dispatched to other sister units.

There are various processes of solidification of molten steel in the SMS. Earlier the most

popular process used was that of ingot casting. In this process molten steel was cooled in

huge containers in form of large blocks called ingots. They were then dispatched to other

units. But cooling and solidification of steel being a complicated process, ingot casting

process became obsolete. In due course of time a new method of casting known as

Continuous Casting was introduced which was not only energy efficient compared to its

predecessor but also very time saving.

Solidification in continuous casting (CC) technology is initiated in a water-cooled open-

ended copper mould. The steel shell which forms in the mould contains a core of liquid steel

which gradually solidifies as the strand moves through the caster guided by a large number

of roll pairs. The solidification process initiated at meniscus level in the mould is completed

in secondary cooling zones using a combination of water spray and radiation cooling.


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CONTINUOUS CASTER: BRIEF LAYOUT

Continuous Slab Caster is an integral part of the SMS unit of any integrated steel plant. It is

a unit which is responsible for solidification of steel produced in the SMS and its subsequent

despatch to other sister units of the steel plant.

There are various types of slab casters used in different steel plants all over the world.

Among them the three most used are vertical slab caster, vertical with bending and

continuous curve type.

The type of slab caster used in SMS-II of R.S.P., Rourkela is of the continuous curve type. It

comprises of various parts viz.

Ladle Tundish

Mold

Paired rollers

Segments

Straightener Withdrawal Unit

Electric arc/ Gas arc slab cutter

Summary of different components in the continuous casting process.

Component Primary Task Secondary TaskLadle Transport and hold the

liquid steelFacilitate inclusion

removalLadle Turret Position full ladles over

the tundish and removeempty ones

Free the cranes forhigher productivity

Tundish Act as a buffer betweenladle and mold

Facilitate inclusionremoval

Mold Cool down the liquid steel to form asolidified shell

Strand System Further cool the strand to fullysolidified and straighten the strand


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Layout diagram of continuous slab caster

Sl. No. Units/ Components

1 Ladle Turret

2 Tundish/ Tundish Car

3 Copper Mold4 First Zone

5 Strand Guide

6 Straightener Withdrawal Units

7 Dummy Bar Disconnect Roll

8 Torch Cut Off Unit

9 Dummy Bar Storage Area

10 Cross Transfer Table

11 Product Identification System

This is the basic layout of the continuous casting mill in SMS-II of Rourkela Steel Plant. To

see another picture of the CCM refer figure 2, Appendix 2.


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STEP BY STEP SEQUENCE OF SLAB CASTING IN CCM SMS-II, RSP

Production and feasibility

This study is the first step in the designing of a continuous casting machine. First, the

product end-use dictates the quality, grade and shape of the cast product (billet, bloom,

slab, beam blank, and/or round). Considerations are then made based on desired annual

tonnage, liquid steel availability, and anticipated operating hours. Then, the machine design

considerations can be made for the number of strands and cast speeds to match the liquid

metal supply from the melt shop. The caster in SMS-II, RSP is a continuous slab caster and it

has been designed keeping in mind all the above factors.

Overview

Since the whole continuous caster is open at both ends i.e. at the input end of the mold and

the output end after the 13th

segment it is not possible directly to pour the molten steel into

the mold. A dummy steel bar has to be inserted into the caster just below the mold. It thus

prevents the running away of the molten steel from the mold by sealing the lower end.

LHF/ARS

Before the molten steel is inserted into the mold it is tapped from the converter into the

steel ladle on a self propelled steel car at a temperature of 16500C. It is then taken into a

Ladle Heating Furnace (LHF) by means of one of the two 250 T Over Head Cranes. LHF is an

AC furnace where the steel is initially purged by means argon purging from the bottom of

the ladle. As per requirement, the composition of steel is modified through the alloying

system and Al. wire feeding system. Arcing facility is provided to increase the temperature

of steel, if required so as to make it suitable for casting.Argon rinsing station (ARS) is also situated in the same bay as LHF. It has all the facilities of

LHF but without the arcing. This is utilized during LHF Shut down or any other exigency

condition.


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Parameters

No. of ladles = 17.

Total volume = 30.5 M3.

Capacity of Ladle = 165 T (Max.)

Heat size = 150 T (Nominal)

Capacity of tundish = 30 T (Approx.)

Ladle life achieved = 125 heats (Max.)

Highest tundish sequence achvd. = 6.2 heats.

Capacity = 150/165 T

Power of LHF = 33 KV

No. of electrode = 3

Electrode = 850 mm

Heating rate ( with 24 MVA) = 40C/Min.

Liquid Steel Transfer

There are two steps involved in transferring liquid steel from the ladle to the molds. First,the steel must be transferred (or teemed) from the ladle to the tundish. Next, the steel is

transferred from the tundish to the molds. Tundish-to-mold steel flow regulation occurs

through orifice devices of various designs: slide gates, stopper rods, or metering nozzles, the

latter controlled by tundish steel level adjustment.

Tundish Overview

The shape of the tundish is typically rectangular, but delta and "T" shapes are also common.

Nozzles are located along its bottom to distribute liquid steel to the molds. The tundish also

serves several other key functions:

Enhances oxide inclusion separation

Provides a continuous flow of liquid steel to the mold during ladle exchanges

Maintains a steady metal height above the nozzles to the molds, thereby keeping

steel flow constant and hence casting speed constant as well (for an open-pouring

metering system).

Provides more stable stream patterns to the mold(s)


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Mold

The main function of the mold is to establish a solid shell sufficient in strength to contain

its liquid core upon entry into the secondary spray cooling zone. Key product elements are

shape, shell thickness, uniform shell temperature distribution, defect-free internal and

surface quality with minimal porosity, and few non-metallic inclusions.

The mold is basically an open-ended box structure, containing a water-cooled inner lining

fabricated from a high purity copper alloy. Mold water transfers heat from the solidifying

shell. The working surface of the copper face is often plated with chromium or nickel to

provide a harder working surface, and to avoid copper pickup on the surface of the cast

strand, which can facilitate surface cracks on the product.

Mold heat transfer is both critical and complex. Mathematical and computer modelling are

typically utilized in developing a greater understanding of mold thermal conditions, and to

aid in proper design and operating practices. Heat transfer is generally considered as a

series of thermal resistances as follows:

Heat transfer through the solidifying shell

Heat transfer from the steel shell surface to the copper mold outer surface

Heat transfer through the copper mold

Heat transfer from the copper mold inner surface to the mold cooling water

Mold Oscillation

Mold oscillation is necessary to minimize friction and sticking of the solidifying shell, and

avoid shell tearing, and liquid steel breakouts, which can wreak havoc on equipment and

machine downtime due to clean up and repairs. Friction between the shell and mold is

reduced through the use of mold lubricants such as oils or powdered fluxes. Oscillation is

achieved either hydraulically or via motor-driven cams or levers which support and

reciprocate (or oscillate) the mold.

Mold oscillating cycles vary in frequency, stroke and pattern. However, a common

approach is to employ what is called "negative strip", a stroke pattern in which the


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downward stroke of the cycle enables the mold to move down faster than the section

withdrawal speed. This enables compressive stresses to develop in the shell that increase

its strength by sealing surface fissures and porosity.

Secondary Cooling

Typically, the secondary cooling system is comprised of a series of zones, each responsible

for a segment of controlled cooling of the solidifying strand as it progresses through the

machine. The sprayed medium is either water or a combination of air and water.

Strand Containment

The containment region is an integral part of the secondary cooling area. A series of

retaining rolls contain the strand, extending across opposite strand faces. Edge roll

containment may also be required. The focus of this area is to provide strand guidance and

containment until the solidifying shell is self-supporting.

In order to avoid compromises in product quality, careful consideration must be made to

minimize stresses associated with the roller arrangement and strand unbending. Thus, roll

layout, including spacing and roll diameters are carefully selected to minimize between-

roll bulging and liquid/solid interface strains. Strand support requires maintaining strand

shape, as the strand itself is a solidifying shell containing a liquid core that possesses

bulging ferrostatic forces from head pressure related to machine height. The area of

greatest concern is high up in the machine. Here, the bulging force is relatively small, but


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the shell is thinner and at its weakest. To compensate for this inherent weakness and

avoid shell rupturing and resulting liquid steel breakouts, the roll diameter is small with

tight spacing. Just below the mold all four faces are typically supported, with only the

broad faces supported at regions lower in the machine.

Bending and Straightening

Equally important to strand containment and guidance from the vertical to horizontal

plane are the unbending and straightening forces. As unbending occurs, the solid shell

outer radius is under tension, while the inner radius is under compression. The resulting

strain is dictated by the arc radius along with the mechanical properties of the cast steel

grade. If the strain along the outer radius is excessive, cracks could occur, seriously

affecting the quality of the steel. These strains are typically minimized by incorporating a

multi-point unbending process, in which the radii become progressively larger in order to

gradually straighten the product into the horizontal plane.

After straightening, the strand is transferred on roller tables to a cut off machine, which

cuts the product into ordered lengths. Sectioning can be achieved either via torches or

mechanical shears. Then, depending on the shape or grade, the cast section will either be

placed in intermediate storage, hot-charged for finished rolling or sold as a semi-finished

product. Prior to hot rolling, the product will enter a reheat furnace to adjust its thermal

conditions to achieve optimum metallurgical properties and dimensional tolerances.


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Relevant Formulas Applicable In The CCM

During the process of secondary cooling basically 3 types of heat transfer occur in the

segments viz.

Radiation

The predominant form of heat transfer in the upper regions of the secondary cooling

chamber, described by the following equation:

Conduction

As the product passes through the rolls, heat is transferred through the shell as

conduction and also through the thickness of the rolls, as a result of the associated

contact. This form of heat transfer is described by the Fourier Law:

Convection

This heat transfer mechanism occurs by quickly-moving sprayed water droplets or mist

from the spray nozzles, penetrating the steam layer next to the steel surface, which then

evaporates. This convective mechanism is described mathematically by Newton's Law of

Cooling:

Q = h A (Ts Tw)

Shell Growth

Shell growth can be predicted by the Ficks Law i.e. L = V ( D / K )2

Q = E A ( TS TA4

)

Q = k A ( Ti To )


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Initial shell formation and oscillation effect

Early solidification in continuous casting occurs in the form of partial freezing of the

meniscus curvature originating from the mould liquid contact point. Prevention of sticking

and tearing of this initial thin shell during the descent of the solidifying strand is one of the

major functions of the CC mould. To minimise shell sticking and tearing, friction between

the strand surface and mould wall must be kept below a critical level depending upon the

shell strength. Minimisation of the friction and continuous release of the shell from the

mould have been achieved through the introduction of mould oscillation aided by

lubrication.

Lubrication mechanism in the mould

Lubrication in the slab mould arises from the infiltration of mould slag into the strand

mould gap. The layering of the slag in the gap is shown in figure 4. The friction in the mould

is considered to originate from two mechanisms. The motion of the mould relative to the

solidified shell gives rise to a frictional force due to the viscosity of the slag film. Thefrictional force generated through this mechanism, termed liquid friction f is given by f =

h(Vm Vc)/d where, Vm = mould speed, Vc = casting speed, h = viscosity of liquid slag film,

and d = thickness of slag film.


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Nozzle Characteristics

The demand for improved product quality and increased productivity has focussed on the

need for more efficient systems of spray cooling during continuous casting. Nozzle

characteristics should be investigated and test procedures developed to measure cooling

patterns and heat transfer. Improved nozzle design and air/water systems gives in better

water distribution and this reduces corner crackingand core segregation. There are also

important operational benefits which enable operational benefits which enable expansion

in the product mix.

Why the need for optimization?

Large scale modernization of the casting machine.

Significant changes in the casting operations due to widening of the product mix.

Elimination of quality problems attributable to the cooling process.

To improve product quality, energy and time efficiency.

Maintenance problems

The nozzles used in the continuous caster require maintenance from time to time to keep

up their efficiency and effective cooling of the slabs. Often many small diameter air and

water pipes are not shaped and welded according to the original drawings when they are

replaced during maintenance. Pipes are often bent and may be out of position due to

either thermal effects or mechanical impact. As a result water jets impinge on the supportrollers instead of the slab surface. To counteract the problem of misalignment, the

alignment pins of the nozzle are sometimes removed which causes further misalignment

difficulties.

Heat Transfer Coefficient

According to an experiment carried out at the Lechler Laboratories (refer figure 3,Appendix 2) the nozzles of the cooling zone show a stagnating HTC at a water pressure

above 4 bars. In fact the HTC shows a slight reduction at higher pressures. Due to lack of


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compressed air the existing nozzle performed worse than a conventional single fluid water

nozzle. This explains why no increase in casting speed could be obtained despite increase in

water pressure and flow.

Modern Air Mist Nozzles

The essential features of modern air mist nozzles are the mixing chamber, extension pipe

water and air inlet adapters and their internal geometries, as well as the geometry of the

nozzle tip. These components must be precision designed with the aid of a computer

model to assure a high heat transfer coefficient, stable spray angles and uniform liquid

distribution. These modern air mist spray nozzles have a number of important advantages:

Reduced incidence of surface and corner cracking and core segregation due to the

improvement in liquid distribution and reductionin cooling water flow.

Enhancement of caster operating conditions for an enlarged product mix due to

wider turn down ratio and optimization of air/water ratio.

Reduced maintenance and pipe costs due to simple and rigid nozzle mounting and

spray piping.

Improvement in operational safety due to perfect alignment of nozzles and spray

piping and reduction in nozzle clogging.


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Simulation Of Casting Process

Continuous casting process can be simulated and optimised in various softwares.We usedsimulation software called COMSOL Multiphysics. COMSOL Multiphysics supplies a number

of easy-to-use tools and commands to help with modelling and analysis. COMSOLMultiphysics(formerly FEMLAB) is a finite element analysis and solver software package for

various physics and engineering applications, especially coupled phenomena, or

multiphysics COMSOL Multiphysics also offers an extensive and well-managed interface to

MATLAB and its toolboxes for a large variety ofprogramming, preprocessing and

postprocessing possibilities. COMSOL Multiphysics is a powerful interactive environment for

modelling and solving all kinds of scientific and engineering problems based on partial

differential equations (PDEs). With this product one can easily extend conventional models

for one type of physics into multiphysics models that solve coupled physics phenomena

and do so simultaneously. Accessing this power does not require an in-depth knowledge of

mathematics or numerical analysis. Thanks to the built-inphysics modes it is possible to

build models by defining the relevant physical quantitiessuch as material properties,

loads, constraints, sources, and fluxesrather than by defining the underlying equations.

COMSOL Multiphysics then internally compiles a set of PDEs representing the entire model.

Solving PDEs generally means you must take the time to set up the underlying equations,

material properties, and boundary conditions for a given problem. COMSOL Multiphysics,

however, relieves you of much of this work. The package provides a number of application

modes that consist of predefined templates and user interfaces already set up with

equations and variables for specific areas of physics. Special properties allow the selection

of, for instance, analysis type and model formulations. The application mode interfaces

consist of customized dialog boxes for the physics in sub domains and on boundaries, edges,

and points along with predefined PDEs. A set of application-dependent variables makes it

easy to visualize and post process the important physical quantities using conventional

terminology and notation. Adding even more flexibility, the equation system view allows

you to easily examine and modify the underlying PDEs in the case where a predefined mode

does not exactly match the application you wish to model.
http://en.wikipedia.org/wiki/Finite_elementhttp://en.wikipedia.org/wiki/MATLABhttp://en.wikipedia.org/wiki/Programminghttp://en.wikipedia.org/wiki/Programminghttp://en.wikipedia.org/wiki/MATLABhttp://en.wikipedia.org/wiki/Finite_element


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COMSOL Multiphysics offers various fields called modules to work on.Basic available

modules include

AC/DC Module

Acoustics Module

CAD Import Module

Chemical Engineering Module

Earth Science Module

Heat Transfer Module

Material Library

MEMS Module

RF Module

Structural Mechanics Module

We simulated the process of spraying mist (mixture of water and air) through nozzle on

slab being casted. Temperature of slab is different throughout the slab, and so is water

velocity. As shown in figures, water velocity changes as slab passes through the

continuous caster.

In figure one (Appendix 1), colour plot of velocity distribution is shown along with the

colour indicator bar. As can be seen, water velocity increases as water exits the nozzle

and moves on surface of slab. Figure two (Appendix 1) is velocity contour

representation of similar simulation. In figure one (Appendix 2) we can also have a view

of the indicative temperature coloured plot of the longitudinal cross section.


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Conclusion

The process of solidification during continuous casting of steel is dynamic in nature. A

host of issues like heat transfer, friction/lubrication at the solidliquid interface, high-

temperature properties of solid etc. add to the complexity of the solidification

process.

Computational fluid dynamics and other fluid flow techniques are being used

extensively in the design of new continuous casting operations, especially in the

tundish, to ensure that inclusions and turbulence are removed from the hot metal,

yet ensure that all the metal reaches the mould before it cools too much. Slight

adjustments to the flow conditions within the tundish or the mould can mean the

difference between high and low rejection rates of the product.

Through this report of ours we have tried to throw some light on the continuous

casting process and highlight some areas of future improvement in this area thereby

improving the efficiency and effectiveness of steel making process as a whole.


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Appendix 1

Figure 2

Figure 1


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Appendix 2

Figure 2

Figure 3

Temperature Field of Longitudinal Cross Section

Figure 1


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References

1. Continuous Casting of Steel: Basic Principles,Published in the website http://www.steel.org authored by Bruce Kozak & Joseph

Dzierzawski.

2. Improved secondary cooling for continuous casting,Paper authored by Jurgen Frick (Director, International Primary Metals Division (Speaker),

Roman Haap (Diploma Ing./ Technical Support Engineer, Lechler GmbH & Co KG).

3. Solidification Control In Continuous Casting Of Steel,Paper authored by S Mazumdar and S K Ray, R&D Centre for Iron and Steel, Steel Authority

of India Ltd (SAIL), Ranchi, India.

4. An optimization procedure for the secondary cooling zone of a continuous billetcaster- Published in The Journal of The South African Institute of Mining and

Metallurgy JANUARY/FEBRUARY 1999 authored by D. deV. van der Spuy, I.K. Craig

and P.C. Pistorius.

5. Continuous Casting, Published in the websitehttp://wikipedia.org
http://www.steel.org/http://wikipedia.org/http://wikipedia.org/http://wikipedia.org/http://www.steel.org/

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