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PRESENTATION OF LEARNING

Prepared by:

Engr. Yaseen Raza HaiderTrainee EngineerInduction Furnace

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Dedicated to...

My Parents

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CONTENTS

Introduction

Refractory

Amreli steel is the largest manufacturer of steel reinforcement bars in Pakistan equipped with INDUCTION FURNACES of 28MT capacities, LRF, and CONTINIOUS CASTING MACHINE...

CCM

Conclusion

Raw Materials, Melting Principle, floor operations, Alloying

Process, Parameters, Product

Ladle preparation, Ladle operation, furnace lining

Utilities FES, RO plant, water complex

Induction Furnace

SLAG PROCESSING

AREA

INDUCTION FURNACE -2

CCM INDUCTION FURNACE -1

WATER COMPLEX FES

SCRAP YARDVEZANI SHEAR

LOGISTICS

SCRAP

LINNING AREA

STORE5

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SCRAP

Raw Material:

Steel Scrap HMS(Heavy Melting Scrap) Shredded Scrap Bundles

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LOGISTICS

Logistics is responsible for :

Availability of scrap to the PlantInventory ControlDistribution of ScrapWarehousing of Scrap Transfer billets to the Rolling mill

ServicesCranesGrabsLoadersDumpers

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INDUCTION FURNACE

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INDUCTION FURNACE

The high frequency alternating current (AC) is passed through the water-cooled coil/ primary coil

Generates intense fluxes/ high magnetic field in scrap

Magnetic flux induces eddy currents in the secondary (scrap)

The resistance offered by secondary to these eddy currents causes heat generation

Scrap gets melt

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There are 2 Induction Furnaces 2 Crucibles at each Induction

Furnace Capacity 28 MT Melting Power 10 MW Duration: 2 hours Temperature: 1670 oC Water LPM: 1800 – 2200 Pressure: 4.5-5.0 Bar

INDUCTION FURNACE

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Copper Coil = 08 Number of turns = 24 Bottom Stainless Steel Coil (No. of

Turns) = 04 Top Stainless Steel Coil (No. of

Turns) = 03 Yoke = 12 Fiber Glass supports = 08

INDUCTION FURNACE-DESIGN

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28 MT 25 MT

SS-Top turns not present SS-Top turns available

Copper turns = 22 nos Copper turns = 24 nos

Teflon Sheets Nomex paper

Hard rubber with Silica tapping Double mica

FRP available FRP not available

Copper turn Height = 95mm Copper turn Height = 80mm

Copper turn Width = 45mm Copper turn Width = 40mm

Total Furnace height = 3680mm Total Furnace height = 3600mm

COMPARISION OF 28MT & 25 MT INDUCTION FURNACES

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Transfer Scrap From Scrap bay To Trolley

Transfer Scrap From Trolley To Vibrator Vibrator Charge The Scrap Into The

Furnace After Melting Scrap, Slag-off Sampling Before Alloy Addition and

After Alloy Addition Alloy Additions Temperature Check Tapping Cleaning Furnace Floor

INDUCTION FURNACE-FLOOR OPERATIONS

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INDUCTION FURNACE-RAW MATERIALS

ScrapMill ScaleSandFerroalloys

1. Ferro-Silicon2. Ferro-Manganese3. Silico-Manganese

Pet Coke

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Furnace Electrical Operation

Electrical parameters of the furnace

Power (Up to 10MW) Current (2400 to 3000 A) Voltage (3100 to 3500 V) Frequency (250 to around 350 Hz) Power Factor (Around 0.80 to 0.99) Earth Leakage (0 to 2A) Water Conductivity (0-12)

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Grid Station

Transformer Generator Panel

Converter

ChokeInverterCapacitor

Furnace

Furnace Electrical Operation

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Water Circulation Inlet water pressure (M)= 3.5-4.5 Bar Outlet water Pressure (M)= 2.5-3 Bar Inlet water pressure (S) = 2.5-3 Bar Inlet Water Temperature = 30 oC Outlet Water Temperature = 40-45 oC

(must not exceed 80 oC) Water Flow rate in coils = 1600 to

1900 LPM Furnace Tilting Operation By Hydraulic

Pressure of Oil (approx. 150 bar)

Furnace Mechanical Operation

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GRADES COMPOSITION

BS 4449-3 (Yellow) C(0.20-0.24%), Mn ( 0.55-0.70%), Si(0.15-0.30%), S & P(<0.05%) C.E 0.37

BS 4449-2 (Blue) C(0.26-0.30%), Mn ( 0.60-0.80%), Si(0.15-0.30%), S & P(<0.05%) C.E 0.39

BS 4449-1 (Green) C(0.18-0.26%), Mn ( 0.55-0.70%), Si(0.15-0.30%), S & P(<0.05%) C.E 0.36

Special grade (Red) C(0.22-0.25%), Mn ( 1.05-1.15%), Si(0.20-0.30%), S & P(<0.05%) C.E 0.48

Special grade (Black) C(0.30-0.34%), Mn ( 0.60-0.80%), Si(0.15-0.30%), S & P(<0.05%) C.E 0.40

INDUCTION FURNACE-GRADES

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REFRACTORY REFRACTORY DEPARTMENT

Furnace Lining

Ladle Preparation

Ladle Operation

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REFRACTORY DEPARTMENT – FURNACE

LINING

FURNACE LINING Material with high melting pointRetain strength at high temperaturesThermal shock absorbance

Acidic linning is used because Process is acidic(Acidic Slag is formed)Ease of availabilityLow in costEasy to shape

It consist ofSiO2 - 98.5%Al2O3 – 0.02%Fe2O3 – 0.02%Boric acid (H3BO3) 1-1.2%

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Former is used to prepare efficient lining. Two types of former are used.

FURNACE LINNING FORMERS Meltable former

Removable former

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FURNACE LINING STEPS Bottom preparation Former placementSide walls filling Three-arm vibrator placementFurnace Support preparation

REFRACTORY DEPARTMENT – FURNACE

LINING

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REFRACTORY DEPARTMENT – LADLE

PREPARATION AREA

Linning preparation for furnaces Mixxing/preheating of linningLinning/ Repairing of ladle

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REFRACTORY DEPARTMENT – LADLE

OPERATION AREA

Pre heating of ladleSlide gate assembly repairing Slag/jam removal from ladle

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Ladle Tundish Copper Mold Tube

primary Cooling

Apron Rollers

Secondary Cooling

Nozzle Zone-I, II

Withdrawl Unit

Entry Rollers

Idle Roller

Exit Rollers

Crop & Pinch

Precutting Roller Table PCRT

Auto cutter

Discharge Roller Table

Pusher

Cooling Bed

Stock-Yard

CONTINUOUS CASTING DEPARTMENT

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CONTINUOUS CASTING DEPARTMENT

CCM Machine

Material of Mold Tube: CopperMaterial of Mold jacket Stainless steelWall thickness of mold tube 12 mmLength of Mold Tube 900 mmTop inner size of Mold tube 154 mmBottom inner size of Mold Tube 152.5 mmCoating of thickness of Chrome 0.08 mmMetallurgical length of Billet 9.2 MetersCasting size (150 x 150)mmMachine radius 6/11Casting speed 1.1 to 1.3 m/sDistance between Mold and jacket 4 mmOscillation frequency for 100 CPMStoke length oscillation 6 mmRequired Temp of Metal in Tundish 1530 - 1545 oC

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Metallurgical lengthThe length at which core of billet solidifies is called metallurgical length.

Metallurgical length can be calculated by

L= (A2/4k2) x VL = Metallurgical lengthA = Crossectional AreaK = ConstantV = Casting SpeedAlso by

S = K√ (L/Vc)

CONTINUOUS CASTING DEPARTMENT

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Flow of water in primary cooling zone is about 1500 LPM Water flow inlet pressure = 7bar Water flow outlet pressure = 5 bar Secondary cooling system consists of three zones

1. Spray ring zone contains 55 LPM2. Zone I cooling system contains 35 LPM3. Zone II cooling system contains 25 LPM

CONTINUOUS CASTING DEPARTMENT

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Final product obtained from CCM is billet 150mm x 150mm. There are different colour codlings for different cutting lengths for the billets

CONTINUOUS CASTING - PRODUCT

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WET LAB

BILLET INSPECTION

SPECTRO LAB

QUALITY CONTROL DEPARTMENT

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Spectrometer-used for the analysis of Furnace samples & billet samples

Can analyze 24 elements at a time Carbon, Silicon, Manganese, Sulfur,

phosphorus and Carbon Equivalent are matter of importance

Basic Components of Spectrometer are:Electrode or Source, Detector, Analyzer

QUALITY CONTROL DEPARTMENT – SPECTRO

LAB

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QUALITY CONTROL DEPARTMENT –WET LAB

Mill Scale and Ferroalloys analysis Sieve analysis for Lining Sample Water sample analysis Hardness, TDS and PH calculations

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QUALITY CONTROL DEPARTMENT – BILLET

INSPECTION

Two types of billet inspection

Visual

Surface cracks

Pin holes

Blow holes

Dimensional

Rhombidity

Cross section

Length

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APC Hood4 No’s Spark Arrestor

Impeller

Hopper Flow Conveyor

UTILITIESFUME EXHAUST SYSTEM

FES

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CONCLUSION & SUGGESTIONS

HSE DepartmentSaftey inspectorsAppreciation awards for workers/saff

BEST PERFOMENCE

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