success in electric steelmaking arccess eaf...

Success in Electric SteelmakingARCCESS® EAF TECHNOLOGYARCCESS® EAF TECHNOLOGY

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SMS SIEMAG Steelmaking

You want to achieve even better results manufactur -ing flat and long products. We have been supplyingsolutions for electric steel production for more than100 years.

Technologically advanced design and quality con - struction are standard for our plants. This is reflectedin our impressive list of worldwide references thatclearly prove the business success they ensure withstable, reliable operating routines.

We manufacture metallurgical plants and rolling millsat the highest level. First-class products, extensiveservices, and custom solutions cement our excellentreputation. Equally convincing are our solutions andsystems because they unite cutting-edge technologyand efficiency with quality and reliability.

A global leader in industrial plant construction, SMS Siemag supplies the full range of products forthe steel, aluminum, copper, ferrous alloy and non- ferrous metal industry.

Here you can choose from a wide range of plants for hot metal including all areas of steel production, continuous casting, and rolling technology right up tofinishing and tempering mills for hot and cold strip.

One focus of our Steelmaking Plants and ContinuousCasting Technology Division is electric arc furnacetechnology. That is evident in the 1,400 plants we

have supplied so far. Included here is the full range ofproducts for electric arc furnaces, auxiliary equipmentand gas cleaning plants.

Whatever your requirements, you have a wide choice of turnkey plants, from stand-alone furnacesto all-inclusive plants complete with control and optimization systems, as well as engineering and on-site support.

for your successSOLUTIONSSOLUTIONS

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OUR PLEDGE TO YOU

Expect the best systems designed and manufacturedto ensure rapid run-up and reliable, continuous opera-tion.

You can also count on eco-friendly, resource-savingproduction. We team up with you to achieve yourproject goals. Plus, after your plants go on-stream,we stay in close contact to support you in the future.

2 Solutions for your success

4 ARCCESS® EAF Technology

boosts your business

6 ARCCESS®-Technological modules

14 X-Melt®-Electric arc furnaces

18 Alternating current electric arc furnaces

20 Direct current electric arc furnaces

22 CONARC® – Two in one

24 Gas cleaning plants – Part of our nature

26 X-Pact® in steelmaking and

secondary metallurgy

28 Service – The future builds on the past

Contents

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ARCCESS® Technology

ARCCESS® stands for success with electric arc furnace technologyfrom SMS Siemag. All ARCCESS®

components are dedicated to minimizing the cost of electric steel production. That’s how yourinvestment pays off even faster.

To help you gain a great deal, wedraw on decades of experience in electric arc furnace technology,metallurgy, and optimized pro -cesses, to offer you the most cost-effective solutions for your business.

ARCCESS® – building

your success

Here’s how you benefit from ourexperience:

Lower production costsHigher productivityBetter-quality steel gradesSteeper run-up curvesLonger running times with less maintenance

ARCCESS® strategies

Teaming up with you, we draw upARCCESS® strategies geared foryour production requirements.

Reduced production costs from our burner and injection tech-nologyIncreased productivity with short tap-to-tap times and ideal shell geometryExcellent energy result with FEOS, our innovative metallur-gical Furnace Energy Optimiza- tion System for process control and optimization

boosts your businessARCCESS® EAF TECHNOLOGYARCCESS® EAF TECHNOLOGY

Reference plants

1,300 +, worldwide, wide-rangingResearch & Development

continuous,customer-oriented,successful

Plant Technology

innovative, sound, sophisticated


Process know-how

long-term, established, reproducible

ARCCESS®

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Technological modulesARCCESS®ARCCESS®


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CHARGE MATERIALS

Scrap

In former times, electric arc furnacesfor steelmaking used scrap as themain charge material. Mean while,to allow for equalizing price fluctu -a tions on the raw materials markets,modern electric arc furnaces aredesigned to efficiently process avariable mix of scrap, direct-reducediron and liquid pig iron. Our EAFscome with large shells and extraplant technology to give you maxi-mum versatility.

Cold DRI

Direct reduced iron, or DRI, is thepreferred choice for high-qualitysteel grades. It produces steel withlow sulfur and phosphor contents,combined with reduced nitrogen.This level of purity is necessary formost flat steel products as well asspecial grades for long products.

Hot DRI

The production process for directreduced iron allows drawing thematerial from the shaft furnace athigh temperature, then feeding itcontinuously into electric arc smelt -ing at around 600°C.

The hot direct reduced iron, orHDRI, utilizes the thermal energyfrom DRI production and is feddirectly into the EAF via a specialconveyor system.

That offers you two advantages:Lower energy consumption compared to cold DRIHigher productivity

A cooperation agreement betweenSMS Siemag and Midrex awards the two companies exclusive rightsto market steelworks equipped with CSP® plants and upstreamMIDREX® Direct reduction plants.It’s a perfect combination. Why?Because MIDREX® Direct reductionand steelworks technology fromSMS Siemag with downstreamCSP® give you an ideally coordinatedminimill solution for energy-efficient,cost-effective production of high-grade hot strip.

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Hot metal

Using hot metal as the charge material in your electric arc furnace,you can achieve lower charge costsand high degrees of purity. So hereis an attractive alternative to con-ventional methods. Our plants useup to 80 percent hot metal. Thatgives you high-quality steel gradesat low charge costs.

The charging process developed by SMS Siemag features a speciallydesigned launder. First, a chargingcrane or transport car with liftingfunction transfers the liquid pig ironfrom a ladle into the launder. Thenthe launder charges the liquid pigiron through the slag door into theelectric arc furnace.

A glance at the operating results clearly shows you the benefits ofusing liquid pig iron as a chargematerial.

Extremely low electricity consumptionHigh liquid steel purityHigh productivity


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MECHANICS

Single-bucket charging

Our preferred solution for electricarc furnaces is single-bucket charg -ing. It comes with key advantages:

30% higher productivity than standard furnacesHigh yield efficiency with long electric arcsReduced specific losses using furnace heat to heat the scrapEfficient use of burner systems to support the smelting process using a higher scrap pillarHigh productivity at low energy costs

Split bottom shell

Also available in our supply scopeis a two-part bottom shell. Thatmakes it easier to replace the wearzone of the bottom shell.

Furthermore, it gives you the option to increase the life-time ofthe refractory wearing zone by theintegration of cooling systems.

Exchange shell

technology

Developed by SMS Siemag, thistechnology ensures much shorterdowntimes and high plant effectiveness.

You can replace top and bottomshells either separately or to gether.As a result, regular maintenance ispossible outside the productionline.

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Coal injection system

Injecting carbon material into theliquid bath is necessary to producean effective foaming slag. Only thenyou can operate with long electricarcs through the foaming slag toachieve a high yield. In addition, thelong electric arcs reduce specificelectrode consumption. That’sbecause they require a smaller electric power to pro duce the sameyield.

The coal injection lances are integrated in the copper blocks near the slag zone.

You benefit from:Easy installation and exchangeInjection close to the bath surface

SIS burner function

Also available is an SIS modulewith burner function. It is con-trolled in such way that the scrapis molten down homogeneously.

Oxygen Injection System

[SIS]

Today, oxygen in electric arc fur-naces is the key to cost-effectiveproduction. That’s why we developedour Oxygen Injection System (SIS).Here is what it means for you:

Effective, long oxygen jet from optimized Laval injector nozzlesLow operating costs using hot gas burnersSmall oxygen apertures to prevent injector slaggingOptional oxygen injection withoutburner function


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ELECTRICS

High-performance trans-

formers

SMS Siemag ARCCESS® electricarc furnaces are high-performancesystems equipped with a transfor-mer rating of up to 250 MVA. Thatis equivalent to a specific rating ofmore than 1.5 MVA per t of tapweight.

As a result, ARCCESS® electric arcfurnaces are the world’s mostpowerful melting systems.

Dynamic voltage control adjustmentSequence-switch control of the transformerSequence-switch control of the reactor (optional)Foaming slag control by evaluation of the harmonic current fluctuation

Electrode control and

foaming slag control

Modern, high-performance electricarc furnaces demand special dyna-mics for electrode control. That’swhy we supply fully digital electrode control solutions. Now, within a few milliseconds, thesesystems correct voltage fluctua- tions, to allow a stable electric arcoperation.

SMS Siemag electrode controlmeasures up with:

Digital electrode control with a processor dedicated to the control loopParameters controlled on-screenUser-friendly screen masks and real-time display of process signals and trendsOptional impedance / reactance control

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FEOS FURNACE ENERGY OPTIMIZATION SYSTEM

FEOS – Energy optimiza-

tion system for electric arc

furnaces

It used to be down to experiencedprocess engineers to draw up melting strategies and specify process parameters for differentcharge materials and consistencies.

SMS Siemag has developed asystem that determines all the key processes in your electric arc furnace, then controls them tooptimize energy utilization. This isour Furnace Energy OptimizationSystem, or FEOS.

FEOS is designed to enable yourengineers to adjust all parametersquickly and flexibly so they canadapt the melting strategy in linewith their experience to optimizethe process in the electric arc furnace.

Characteristics of FEOS

It is simple and user-friendly. Youbenefit from these key communi-cation features:

Design of the specific electricarc furnace and structured input of control parameters and limit valuesDocumentation and visualizationof all material and energy flowsCombination of control diagrams(Level 1 controls) and conven-tional control strategiesOffline test of algorithms and parameters with replay mode in a simulation environment

FEOS control basis

The special advantage of FEOS is it controls the regulation signals ofthe output variables that determinethe process. How? By measuring,in real time, the process inputvariables and the pre-set functionsof power control, reactor control,burner control and foaming slagcontrol.


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The results

FEOS has proven its worth in practical operation. The resultsshow that an electric arc furnacerunning with FEOS gives you awhole range of benefits:

Performance controlHigh melting yieldsNo interruptions through switch-offs in borderline temperature areaRapid reaction with simultane-ous reduction of switching frequencyReproducible and efficient electrical energy inputShort tap-to-tap times

Injector controlProcess-dependent use of materials, independently of timeMinimized, effective usage

FEOS – foaming slag

control

FEOS foaming slag control is oneof the most important modules formaximizing the energy efficiencyof your electric arc furnace. It’s amethod we developed to controlthe foaming slag level according tothe furnace noise level.

FEOS – continuous off-gas

monitoring

In the future, FEOS will be ex- tended by the continuous off-gasmonitoring module to detect andevaluate further metallurgical process parameters.

FEOS

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X-MELT®X-MELT®

Electric arc furnaces

Deservedly, with almost 1,400electric arc furnaces in both newconstruction as well as revampprojects, SMS Siemag ranksamong the world’s leading sup-pliers of electric arc furnace technology.

Here is what makes our electricarc furnace design stand out:

Modular designStandardized component groupsLow maintenance

SUCCESS BASED ON

EXPERIENCE

More than 100 years of development,construction and commissioning ofelectric arc furnaces give us a valu-able store of experience. It’s anexpertise strengthened by know-how from former companies KruppIndustrietechnik, MannesmannDemag and GHH. That translates into a capacity to apply the very best methods and designs to ourelectric arc furnaces.


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Furnace roof with

off-gas elbow

Self-supporting stand for the furnace roofRoof elements with tube-gap-tube design and extra slag holders for optimal slag build-upOff-gas elbow as a gas-tight welded tube-to-tube constructionHigh angle of incline of the off-gas elbow reduces slag caking on the lid

Furnace gantry system

Bearing system with wide slewing angle for shell changeRoof lifting system mounted at three points for balanced liftingCouplings with lifting hooks for free access to the furnace roof for maintenance and repairsFast and easy changing of the central refractory hearth

Electrode mast guiding

system

Rectangular shape of the electrode mast for optimal guidance with four guide rollsGood accessibility and exact adjustability for reduced main-tenance and repair costs

EBT – Eccentric Bottom

Tapping

Eccentric bottom tapping was developed and patented by SMS Siemag. Today it is standard for electric arc furnaces world-wide.Automatic cleaning of the bottomedge of the EBT channel

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1 High safety with pneumatically air-cooled cylinderAdditional accumulator for in-creased availability of the tapping system

Upper furnace shell

Tube-gap-tube design for optimal slag adherence with correspond- ing thermal insulationEach panel is separated into two circuits for optimized coolingThe slag door drive is mounted for protection against slag splashing

Lower furnace shell

Eight resting points for the furnace shell and the eccentric bottom area for evenly balanced supportModular, optional installation of copper cooling blocksMinimization of energy losses by selecting the shortest distance between the eccentric bottom tapping and the shell centerCooling vents for thermal circu-lation of surrounding air to pre-vent local overheating

Tilting platform with

rockers

Torsion-stiff performance with Finite Element Model (FEM)Only one tilting cylinder requiredSelf-righting to 0 positionExact guiding by geared guides for exact tilting operationIntegration of additional, water-cooled heat shields on areas under thermal strain

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Today, our X-Melt® electric arc furnaces come with a whole range of innovative design features:

Modular designStandardized component groupsLow maintenance

EBT – Eccentric Bottom Tapping

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1 2

5 6 7

Electrode mast guiding system

Furnace gantry systemFurnace roof with off-gas elbow

Tilting platform with rockersLower furnace shellUpper furnace shell

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FROM PIONEER PER-

FORMANCE TO PEAK

PERFORMANCE

AC EAF – SUPERIOR

EXPERIENCE

Right from the start of electricsteel production, our alternatingcurrent electric arc furnaces havedemonstrated their capability againand again. Over the years, we havesteadily improved our designs.

These state-of-the-art alternatingcurrent electric arc furnaces offeryou an extremely high productioncapacity and a transformer rating of more than 1.5 MVA/t.

Superior performance

Today, our alternating current high-impedance furnaces are state ofthe art. They feature low reactanceon the secondary side as well asan impedance coil on the primaryside of the furnace transformer.

Your advantages:Stable electric arc operationLow energy consumptionLow electrode consumptionFewer electrode breakagesLow force applied to the electrodes and electrode bearing armsLess network interference

High performance

Connecting transformers with arating of up to 250 MVA makeshigh demands on the design of the mechanical equipment. Just as challenging, the water-cooledpanels of the wall and roofelements have to withstand ex tremely high thermal strains.

That’s why the electrical high-cur-rent section from the transformerto the electrodes is specially de-signed to cope with extremely highcurrents and voltages. Our special -

ists know all there is to knowabout building symmetrical high-current systems. This ensureseven power input into the electricarc furnace and prevents localoverheating.

ALTERNATING CURRENT ALTERNATING CURRENT electric arc furnaces


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High current/voltage

Power Conducting Arms (PCA)developed by SMS Siemag performefficient and reliable transfer ofelectrical power to the graphiteelectrodes. That requires control ofultra-high power up to 100 kA, plusinsulation from the conductingcomponents.

These are the special design features of our PCAs:

Copper-plated arms with excellent power conducting propertiesThe option of a small partial circuit which reduces the thermal strain on the water-cooled wall elements

Electrode breakage monitoring system, a safety system patented by SMS Siemag

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DIRECT-CURRENT DIRECT-CURRENT electric arc furnaces

ALL ADVANTAGES IN

ALL NETWORKS

The technology

What sets our direct-current fur naces apart is their low energy and electrode consumption. Theyalso ensure excellent thermal andmetallurgical homogenization ofthe liquid steel. Plus, there is theincreased stirring effect of thedirect-current arc that supports this process.

Compared to alternating-currentelectric arc furnaces, direct-currentfurnaces cause fewer network disturbances, so you can connectthem even to weak electric grids.

Key to the efficiency of a direct-current electric arc furnace is opti-mal central arc positioning. Ourcomputer simulation system foravoiding electric arc deflectionoffers you perfect high-current bus bar system arrangement.

Revamps

It is always worth examining whether your existing bottom elec-trode system should be replacedby SMS Siemag pin-type bottomelectrodes.

Our pin-type bottom electrodesoffer you:

Long service life of more than 2,000 heatsSafe operation with possible bottom electrode wear monitoringRapid change-over times using tried-and-tested methods and toolsHigh safety provided by air coolingTop plant effectiveness and productivity

The bottom electrode

Another element in the success of our direct-current electric arc furnaces is our patented and con-tinually improved pin-type bottomelectrode.

Depending on the current densityrequired, the current is distributedover more than 300 individual steelpins. That ensures a symmetricalload on the bottom electrode,which can also be thermally moni-tored at fixed points. Safety is atop priority in our plants, so thebottom electrode is air-cooled.

The advantages of pin-

type bottom electrodes:

Extremely low operating costsAir-cooled bottom electrodeLong service life, so mainte-nance work can be carried out together with maintenance of the bottom shell brick liningNo interim repairs necessary


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DOUBLE VERSATILITY

Our CONARC® furnaces combinethe technological advantages ofelectric arc furnaces with those ofthe conventional converter blowingprocess. They consist of a singleproduction unit with two identicalshells.

We chose the name CONARC®

to reflect this combination(CONverter ARCing). It gives youthe advantages of free choice ofcharge materials and a wide rangeof steel grades. Depending on the steel grade as well as the avail ability and price of chargematerials, you can vary the per -centages of scrap, hot metal andsponge iron.

Equally flexible is your choice of energy sources with theCONARC® method. You can achieve a converter and arcingphase balance using a suitable mixof electrical and chemical energy.That ensures perfect symmetry between the delayed-action tappingsequence times of the two shells.

Two process steps

CONARC® is optionally equippedwith one swiveling or two stationarytop lances for oxygen blowing. Plus, there are devices for bottomstirring that can be integrated in the shell floor.

The process is divided into two stages:

The converter phase, which involves blowing oxygen onto the melt through the top lance to decarburize it.The electric arc furnace phase, during which electric power is applied to melt the solid material and overheat the bath to tapping temperature.

The world is changing dynamically:you respond with flexibility.

Two in oneCONARC®CONARC®


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CONARC® – METALLURGY WITH FUTURE-ORIENTED FLEXIBILITY

CONARC®

Scrap

CONARC® route – Flexible charge mix

Electric arc furnace – Standard operating range

BOF converter – Standard operating range

HBI/DRI Hot metal

$ $

EAF

BOF

Scrap HBI/DRI Hot metal

Scrap

Hot metal

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RESPONSIBILITY

The moment we start to plan yoursteelmaking plant, we work withyou to promote safety and protection of the environment. To supportyou in this respect, we supply tailor-made plant solutions forsteelworks dedusting, as well as cleaning of primary and secondary gases.

Stages of gas cleaning

Our X-Melt® gas cleaning plantsare carefully coordinated:

Primary gas extraction from the water-cooled off-gas elbow and channeling into the post-combustion chamberPrimary gas cooling with quenching systems or gas coolersSecondary gas extraction using gas collecting hoodsSecondary gas cooling and spark separation in horizontal or vertical gas mixersDust extraction using bag filtersGas emission through the stack as cleaned process gas, clean and environmentally harmless

Improving the future

Here at SMS Siemag, we are con- tinually developing and expandingthe environment-friendliness of the steelmaking process as well asthe treatment of by-products. Ourfocus is on improving the energyimpact and eco-friendly processingof filter dusts.

Steam generation

Steam generation is an efficientway to recover a part of the excess thermal energy from yourelectric arc furnace. It utilizes theextremely high temperature in theprimary off-gas cooling system.This method considerably improvesthe energy efficiency of an electricarc furnace. It makes the recov -ered energy available for other production units.

Part of our natureGAS CLEANING PLANTSGAS CLEANING PLANTS


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Filter dust injection

Filter dust injection also improvesthe ecological impact of electric arcfurnaces. This involves repeatedlychanneling the filter dust back intothe electric arc furnace so that thezinc content in the dust builds upsteadily.

Finally, the enriched filter dustturns from a by-product into acommercial product that can berecycled.

Filter dust processing

SMS Siemag has developed a special process for submerged-arcfurnaces that recycles metallurgicalby-products, including filter dusts.

This technology gives you theopportunity to effectively extractthe metal content, so you gainvaluable raw materials from yourwaste.

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EVERYTHING UNDER

CONTROL

X-Pact® enjoys a great worldwidereputation in the steelmaking andsecondary metallurgy industry. You only have to look at the largenumber of plants in all kinds ofsteelworks we have automatedusing X-Pact®. Whether BOF, EAF or CONARC® melting processes,whether secondary metallurgy orstainless steel production – X-Pact®

automation gives you perfect con-trol of everything from turnkeyplants to stand-alone or part plants.

All-inclusive packages

from SMS Siemag

Here you benefit from our ex -perience in system integration ofthe entire spectrum of drive tech -no logy – from energy supply toinstruments, basic automation, and process optimization. Includedare all the services you require fornew plants as well as revamps.

Process models for calcu-

lating energy, charge

materials and alloys

Energy and material managementgeared precisely to melting be ha-vior is the basis for automatingyour steelworks with X-Pact®. Itcovers all units including meas u-ring, control, and adjustment toensure you apply your processmodels effectively. Complex calculations work out the idealenergy input, charge materials and amount of ferrous alloys.

You increase your productivity bykeeping to close tolerances. Thisresults from careful X-Pact® anal ysisthat enables you to achieve exactfinal temperature, final steelweight and treatment time.

Increased productivity

X-Pact® minimizes treatment re -pe tition, reduces ladle cycle timesand increases the service life ofrefractory linings. That cuts costsand repair workload. There is evenmore you can expect from X-Pact®

metallurgical process models: per-manently lower production costs,higher productivity and consistentfinal product quality.

in steelmaking and secondary metallurgyX-PACT®X-PACT®


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Conventional and

integrated systems

You can choose from conventionalor integrated automation systemsfrom SMS Siemag. That meanscomplete with separate or jointHMI for Level 1 and Level 2.Typical for X-Pact® are featuressuch as process and technical data links from steelmaking to continuous casting and othermetallurgical plants.

Metallurgical process models for the entire steel production process are integral parts of X-Pact® Electrics and Automation.

EAF processCONARC® process

ELECTRICS AND AUTOMATION WITH X-PACT®

Level 3

Production planning and scheduling

(PPS)

Level 2

Steelworks Computer System

Calculation of charge materialsCalculation of alloy materialsMass and energy balanceProcess predictionDetermination of target values for process control

Level 1

Basic automation system

Operating stationsSequence and drive controlsMeasured value processingSignal and data exchange

Level 0

Complete systems for plant equipment

Field instrumentationDrive systemsPower distribution and auxiliary equipment

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More than 100 years of develop-ment, construction and commissioning of machines and plant forthe global steel and nonferrousmetal industry – it all adds up to avaluable store of experience. Andthat benefits you directly when you use our Technical Service.

Wherever you are in the world, X-Cellize® offers you support foryour mechanical equipment, auto-mation, maintenance and processtechnology.

That means our services give youthe backup you expect from a global player in metallurgical plantsand rolling mill technology.

X-Cellize® covers these services:Outsourcing your maintenance and repair workIntegrated Maintenance Management System (IMMS®)Technical assistanceSpare part management, inspection and repair serviceTeleservice / HotlineTraining

How you benefit

Maximum plant effectivenessensures you gain that extra com- petitive edge. Find out for yourselfwhat concrete benefits our serviceexperts can offer you. We willshare all our know-how with youso that you achieve your production goals.

X-Cellize® – Technical service is inour genes.

The future builds on the pastSERVICESERVICE


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TOP PLANT

EFFECTIVENESS:

HIGHER PRODUCTION

YIELD – MINIMIZED

COSTS

It’s a fact often overlooked. Yetplant effectiveness and reliabilityhave a huge impact on quality andvolume of production. Neglectingthese aspects leads to productionlosses, higher production planningand maintenance costs as well asquality problems.

To tackle this issue effectively,SMS Siemag developed its

Integrated MaintenanceManagement System (IMMS®) that maximizes Overall EquipmentEffectiveness (OEE).

Specialists from our TechnicalService (X-Cellize®) analyze anddocument your scope for applyingContinuous Process Optimization.

We advise you on how to achievehigher plant reliability.

We carry out audits designed toimprove your plant effectivenessand cut maintenance costs.

Choosing IMMS® means we design for you a preventive and therefore planned repair strategy comprising four main packages:

I. Technical assistance

II. Spare part management, inspection

and repair service

III. Teleservice / Hotline

IV. Training

MEETING your EXPECTATIONS

H3/

308E

1000

/03/

09 ·

ky ·

Prin

ted

in G

erm

any

SMS Siemag AG

Steelmaking and ContinuousCasting Technology Division

Eduard-Schloemann-Straße 440237 Düsseldorf, Germany

P.O. Box 23 02 2940088 Düsseldorf, Germany

Phone: +49(0) 211 881- 6915Telefax: +49(0) 211 881- 69 82

E-Mail: [email protected]: www.sms-siemag.com

”The information provided in this brochure contains a general description of the performance characteristics of the products concerned. The actual products may not always havethese characteristics as described and, in particular, these may change as a result of further developments of the products. The provision of this information is not intended to haveand will not have legal effect. An obligation to deliver products having particular characteristics shall only exist if expressly agreed in the terms of the contract.“

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