PRESENTED BY-DEEPAK DWIVEDIDEPT. OF METALLURGYOPJIT, RAIGARH (CG)

Steel Melt ShopSteel Melt ShopA Journey Towards ExcellenceA Journey Towards Excellence

STEEL MELT SHOP II

MAJOR FACILITIESMAJOR FACILITIESANNUAL CAPACITY 2.0 MTPRODUCTION 2009-10(UPTO 31/01/10)

65000 T

ELECTRIC ARC FURNACE 02 NO.LADLE REFINING FURNACE

03 NO.

VACUUM DEGASSER 01 NO.CONTINUOUS CASTER 03 NO.

STEEL MELT SHOP II

MAJOR MILE STONESOF SMS-II

sms -2 have been produced 73heats in a day since April.(world’s second largest )

MAJOR MILE STONESOF SMS-II

sms -2 have been produced 73heats in a day since April.(world’s second largest )

STEEL MELT SHOP II

PRODUCTS

STEEL MELT SHOP II

STEEL MELT SHOP II

KEY CUSTOMERS

• RUBM (ROLLING AND UNIVERSAL BEAM ROLLING AND UNIVERSAL BEAM MILLMILL)

• SEMI’S—MSL, JSL, NALWA, BHEL.

STEEL MELT SHOP II

STEEL MELT SHOP - II

STEEL MELT SHOP II

SCHEMATIC DIAGRAM OF EAF

STEEL MELT SHOP II

ELECTRIC ARC FURNACEELECTRIC ARC FURNACE SALIENT FEATURES• MAKE : Sms demag• CAPACITY : 100 MT• TRANSFORMER RATING : 100 MVA• ELECTRODE DIA. : 24"(600 MM)• NO OF OXYGEN LANCE : 4• FURNACE LINING BRICKS : MAGNESIA CARBON BRICKS• TAP HOLE : EBT TYPE

STEEL MELT SHOP II

Functions of EAF:Functions of EAF:1. Melting of inputs and homogenization

of steel bath.2. Raising the temperature of the melt to

≈16200C for tapping.3. Decarburisation.4. Dephosphorisation.5. Slag free and compact stream tapping.

FUNCTIONS FUNCTIONS OF EAFOF EAF

STEEL MELT SHOP II

METALIC INPUTSMETALIC INPUTS:• Hot metal from blast furnace : 30 to 70%• %C : 3.8 to 4.2%• %Si : 0.3 TO 1.0 % • %P : 0.13 max• Temperature : 1280 deg min• DRI (Lumps +Fines) from DRI Plant : 40 to 49%• %C : 0.1 max• %Fe(met) : 81 min• %SiO2 : 3.5 • Scrap : 1 to 5% (optional)

FLUX:FLUX:• Lime from LDP (Lime and Dololime Plant)• Burned dolomite from LDP

OTHER INPUTS:OTHER INPUTS:• Oxygen from Oxygen plant.• CPC (Calcined petroleum coke)

INPUTS FORINPUTS FOR

EAFEAF

ELECTRIC ARC FURNACEELECTRIC ARC FURNACE

STEEL MELT SHOP II

HEAT CYCLE:HEAT CYCLE:Charging Hot metal pouring Melting& Blowing TappingTap to tap time : 53 minEBT filling time : 3 minSlag pot changing/ pit cleaning time: 13 minHot metal pouring time : 5 minArc time : 29 minTapping time : 3 minCONTROL PARAMETERS:CONTROL PARAMETERS:Power in put : 70 to 75 MW Oxygen input : 120 Nm3/minTap Chemistry

%C : 0.05 %P : 0.010% Other elements : Trace

Tapping Temperature : 1620°C

HEAT HEAT CYCLECYCLE

ELECTRIC ARC FURNACEELECTRIC ARC FURNACE

STEEL MELT SHOP II

Melting process in eaf

• EAF shift incharge insure the charge mix preparation as per the instruction of incharge.

• DRI-0-55%

• Hot metal- 0-80%

• Bucket charge- 0-40%

• (scrap+skull+DRI+pig iron)

• Best charge mix combination always try to• Aim for optimum output is mentioned below

which depends upon availability of raw material and power

• Power- 50-72 MW• Hot metal- 50-58%• DRI- 40- 48%• Bucket charge – 0-2%• EAF is switched on and operating on low power

depending on scrap.• Calculate oxygen blown in furnace through VLB

• If the carbon content is high in that condition the extra oxygen will be supplied for the reduction of carbon in the form of

Carbon dioxide

Furnace helper takes the temperature of the melt in EAF .

Temp. of melt should not less than 1600c

• TAPPING

• Shift incharge instructs the PIT side supervisor to get the ladle below the tapping hole of the EAF .before tapping it is ensured that the purging is in open condition .

• During tapping addition of ferroalloys , fluxes and deoxidizer are done.

• Then transfer towards ladle.

Thermocouple circuit of EAF

No of ID fan : 3 nos (2W+1S)Flow value of each fan : 7,50,000 Nm3/hrTotal bag area : 14,862 m2

Air to cloth ratio (PEAK) : 100 Nm3/m2/hr (approx)Pressure drop across bag filter house : 16 mbar (approx)Dust content at outlet of bag house : 20 mg/Nm3

FUME EXTRACTON SYSTEM EAF

FESFES

STEEL MELT SHOP II

FES LINE DIAGRAM

STATUTORY NORMS

STEEL MELT SHOP II

1. AMBIENT NOISE LEVEL - NORMS 6AM to 9PM 9PM to 6AM (Day) (Night)Normal 75 dB 70 dBWork zone 85 dB 85 dB

2. STANDARD PARTICULATE MATTER AT GUEST HOUSE SPM 500 µg/m3 (Max)

3. RESPIRABLE PARTICULATE MATTERSO2 120 µg/m3 (Max) NOx 120 µg/m3 (Max)CO 5000 µg/m3(Max) 4. STACK EMISSSIONS MONITORING SMS NORMSLRF- 1 50mg/m3 (Max)LRF-2x3 50mg/m3 (Max)EAF 1&2 50mg/m3 (Max)RMH bag house 50 mg/m3 (Max)

STATUTORY NORMS

STEEL MELT SHOP II

calculations

• At eaf-

• Dri-0-55%

• Hot metal (si-.2-1.2%,temp. 1100-1380c)-0-80%

• Bucket charge (scrap+skull+dri+pig iron)-0-40%

• Power: 50-72 mw

Example-

• If we want hot metal consist 60kg si then according to the capacity of eaf (60mth/m, total hot metal will consist 360 kg of si,

• Then= si +o2 = sio2

• Sio2 = 360x1.114=410.4

• For maintaining 2 bassisity -410.2x2=820.8 cao is required.

• But pure lime consist approx 85% pure so,

• 100-kg---------- 85kg pure cao

• 820.2 kg ------ 85/100 x 820.8

example

• Silica load x 50% = req. Mgo

• The capacity of eaf 65 ton, if furnace run at 1 MW , tat to tap time is 32 min. , in jspl 70 Mw furnace run

• So, 70 x 30 = 2100kg.

• When it had achieved 73 heat then tap to tap

• Time will =39.45 min.

Super heat

• Lrf ---80c-----slab –20c----tundish –40c ---

casting –30c-----

So super heat is= 20+40+30=90c

Let us assume after 1 min. temp. will raise 5c

And we know that furnace temp. is- 1530c

Supply temp.is 1599 c.

So total temp. raise = 69c1 min temp. raise=5c

For 69c =====5x69= 345

• so furnace will run for around 14 min.

• Due to this super heat furnace wikll run for extra 14 min. but ladle takes time because-

• 1-addition of substances

• 2-cooling of ladle

• 1% addition of any substance results 20-25c temp. drop. We are adding 1.5 ton of sub. Through fafa.so furnace will have to run 7 min.

• So total running of furnace can calculated as =14+7+5=26 min.

• They have a transfarmer of 12 mva at power factor of 0.8so total power consume=9600w

• We are running furnace for 26 min.• So, 60 min power consumption is =9600w• 26 min ----------4160w• That means power req. for 1 ton is 4160 watt• Cost of power for 1 ton melting can also

calculated if 1 watt’s cost is g• Thencost=4160 x g

• Quality control dept.(spectrolab)

• to start Spectrometer we have to press f2 botton .

• Before that loly pop sample have taken from lrf as well as eaf also.

• Sample must be polished . For that purposedisc polisher and automatic polisher is available.

• Automatic polishing machine have been supplied from germeny.

• It consist of ab 60 grit paper. Paper is called as eloxide paper .

• For picking sample sample lancing is used .height of sample lancing is 5 ft.

• It is supplied by shreeram industry.

• Lequous temp. of steel-=

• 1537-(.65x %c+8x%si +5% Mn)

• Wheet powder is a good insulator and it wilkl drop 1-2c.

• Simn-60%mn, 13-15%si

• Fe-si – 70% si

• Hcmn – 70%Mn , 4.8% c

• Al wire – 96% Al

• So, alloy addition = pointed to be need x tonnege of material x100%/%efficiency

STEEL MELT SHOP II

STEEL MELT SHOP II

Ladle Refining Furnace(LRF)Ladle Refining Furnace(LRF)

No. of LRF : 03

Make : Sms demag

Capacity : 100T

Transformer rating : 18 MVA

Salient Features

STEEL MELT SHOP II

1.Refining of steel

2.Achieving desired chemistry.

3.Desulphurisation

3.Thermal and Chemical Homogenization.

4.Raising desired temperature for casting.

FUNCTIONS OF LRFFUNCTIONS OF LRF

STEEL MELT SHOP II

FES FOR LRF :

No of Booster Fan : 1 no.Capacity : 1,00,000 Nm3/hr

Connected to Secondary (Canopy Duct) of Main Fume Exhaust system.

STEEL MELT SHOP II

STEEL MELT SHOP II

VACUUM DEGASSER

LADLE

STEEL MELT SHOP II

Vacuum DegasserVacuum Degasser

Salient FeaturesDesign, Engg and Supply : danieli,italySuction Capacity : 350 Kg/hr at 0.5 torrPump down time : 5 minutes to 0.5 torrVacuum System : 9 Steam ejectors

3 +1condensers works on successive compression of off-gas in a series of steam ejectors.

Argon Stirring : Continuous 16 Nm3/hrs max

STEEL MELT SHOP II

VACUUM DEGASSER

STEEL MELT SHOP II

Functions of VD:

1.Removal of entrapped gases

2.Removal of sulphur by slag-metal reactions promoted by Argon purging.

STEEL MELT SHOP II

BILLET CASTER (UNDER PROJECT)

COMBI CASTER

STEEL MELT SHOP II

Continuous Casting MachineContinuous Casting Machine1.Combi Caster :1.Combi Caster : No. of strands : 04 Machine Type : Combination caster with curved mould Supplier : vai Radius : 12000 mm Mode of straightening : Continuous Strand Center distance : 1800 mm Machine speed• Speed range : 0 to 2.5 m/min• Restranding speed : ≈ 3.0 m/min Length from meniscus in

mould to torch cutter : 32.5 mtrs Casting mode : Powder casting with stopper rod system and

mould EMS system Mould length : 800 mm Metallurgical length : 20.5 mtrs Ladle accommodation : Ladle turret (Butterfly type) Dummy bar system : Chain type dummy bar (Bottom feeding) EMS : Electromagnetic mould stirrer Mould level control : Cs 137 source with stopper rod control. Type of mould : Curved mould with Cu plates for beam blank

and Blooms, Cu tube for rounds.

Oscillation : Hydraulic mould oscillator (Dynaflex) Cutting Device : GEGA Torch cutting machine Cut length : 4.5 to 12 mtrs

STEEL MELT SHOP II

1.1. Combi Caster Combi Caster

420x480x120mm, 355x280x90 mm Beam blank,

285x390mm 250x250 mm Bloom, 200, 255, 220, 305 mm Rnd.

Products

STEEL MELT SHOP II

Continuous Casting MachineContinuous Casting Machine2. Billet Caster (Under project):2. Billet Caster (Under project): No. of strands : 06 Machine Type : Curved heavy duty Type Supplier : CONCAST Radius : 9000 mm Mode of straightening : Continuous Strand Center distance : 1200 mm Machine speed Speed range : 0 to 5 m/min Restranding speed : ≈ 3.5 m/min Length from meniscus in

mould to torch cutter : 27.1 mtrs Casting mode : Powder casting with stopper rod

system andmould EMS system

Mould lengthRounds : 800 mmSquares : 1000 mm

Metallurgical length : 27.1 mtrs Ladle accommodation : Butterfly type Ladle turret Dummy bar system : Rigid type dummy bar (Bottom feeding) EMS : Electromagnetic mould stirrer Mould level control : Co60 source with stopper rod control. Type of mould : Curved tublar Cu mould Oscillation : Electro mechanical Cutting Device : ALBA Torch cutting machine Cut length : 9 to 12 mtrs

STEEL MELT SHOP II

Continuous Casting MachineContinuous Casting Machine2.2. Billet Caster (Under Project) :Billet Caster (Under Project) : : 130x130mm, 150x150mm, 165x165mm

200x200 mmProducts

STEEL MELT SHOP II

Slab caster

• No. of strands:• Machine type:• Supplier:• Mould length:• Metallurgical length:• Oscillation:• Cut length

• 01• Curved mould • Sms demag• 700mm.

• 17.3m

• Hydrulic

• 3.5 to 9m.