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NATIONAL INSTITUTE OF TECHNOLOGYHAZRATBAL, SRINAGAR- 190006 (J&K)

PROJECT BASED INDUSTRIAL PRACTICAL TRAINING AT BHILAI STEEL PLANT (AN INTEGRATED UNIT OF STEEL AUTHORITY OF INDIA LTD.)

CERTIFICATE

This is to certify that Ms. Avani Sharma has completed her winter session in plant practical training from 9-Jan -2012 to 18-feb-2012.

This report is the record of authentic work carried out by the student during the academic year 2011 – 2012.

(Mr. A. K Srivastava) A.G.M Internal Guide

(Mr. Rajesh Devangan) Training Officer

DECLARATION

I Ms. Avani Sharma hereby declare that this report is the record of authentic work carried by me during the academic year 2011-12 in Bhilai Steel Plant (BSP) An integrated unit of Steel Authority (SAIL) Bhilai, District Durg (C.G.)

( )

Signature of the student

(Avani Sharma)

Name of the student

ACKNOWLEDGEMENT

I express my sincers thanks & regards to Bhilai Steel Plant, for giving me the opportunity to

study on the topic “Desulphurization practices and special steelmaking .”

First & foremost I express my heartily thanks to Mr. Rajesh Devangan (Training officer)

my project guide Mr. A.K Srivastava. I am also thankful to Mr. A V. Fuley (Training coordinator

–HRD) V.T. Section.

I also express my heartily thanks to Mr. N. V. Joshi (D.G.M Converter Shop) for their

kind guidance. I also express my sincere thanks to Mr. Sanjay Aggarwal( Senior Manager

DSU) & (secondary) for their valuable assistance .I would also like to thank Mr.

Diwakar ,Mr. Sudhir and Mr.Vishal for their valuable help to complete our project.Last but not

the least I would like to thank all my group members for their kind cooperation to complete this

project work.

Date… AVANI SHARMA

EXECUTIVE SUMMARY

During my six weeks of winter training in the Bhilai Steel Plant, I have done project

research work on “Desulphurization practices and special steel making”.

The project report tells us about the secondary product section and the whole process,

starting from collection of scrap to the lifting of material and its distribution. The initial part of

the report tells about SAIL and importance & performance of Bhilai Steel Plant in the steel

authority. It also tells about the contribution of Bhilai Steel Plant to Sail’s profit. The next part

describes the procedure of selling & distribution the secondary product. And the major

consumer of BSP in this field.

It also throws light on refinment of pig iron which contain about 4-5 % of carbon and

other major detrimental impurities such as S, P, Mn , Si .the above process is done n SMS i.e

steel making shop of the plant which constitutes of the following section:

1. Mixer

2. Desulphurization unit

3. Converter shop.

4 .Secondary unit (VAD , R H,LD)

5. Continuous casting shop

The conclusion deals with the objective of Bhilai Steel Plant to achieve sales analysis of

secondary products. The last portion conclusion & recommendation to improve the functioning

of marketing department of Bhilai Steel Plant.

INDEX

Sr. No. Content Page NO.

Chapter-1 Cover page 1

Chapter-2 Certificate 2

Chapter-3 Declaration 3

Chapter-4 Acknowledgement 4

Chapter-5 Executive Summary 5

Chapter-6 Introduction to B.S.P 6

Chapter-7 SMS -2 brief 26

Chapter-8 Project Report 28

Chapter-9 Conclusion 67

Chapter-10 Limitations 68

Chapter-11 Bibliography 70

CHAPTER -6

INTRODUCTION

STEEL ATHOURITY OF INDIA LIMITED (SAIL)

During struggle for independence, Pt. Jawahar Lal Nehru our first prime minister of

independent India had a very clear vision about the role of steel in the development of our

nation. Although Tata Iron & Steel Co. 9TISCO) established in 1907 marking the beginning of

Indian Steel industry followed by Indian Steel Corporation (1918) they were too small to meet

the development requirement of a big country like ours. Therefore, in the first industrial policy

resolution of the government soon after independence, government decided to establish steel

plant in Public Sector only. However work could be started at faster pace in 1954 when.

Hindustan Steel Limited was formed and the steel plants of 1 MT capacity of each were

established with provision of further expansion at Bhilai, Rourkela and Durgapur with

assistance from USSR, West Germany and UK respectively.

Steel Authority of India Limited (SAIL) is the leading steel-making company in India. It is fully

integrated Iron and Steel maker, producing both basic and special steel for domestic,

construction, Engineering, Power, Railway, Automotive and Defense industries and for sale in

export markets.

Ranked amongst the top ten public sector companies in India in terms of turnover. SAIL

manufactures and sells a broad range of steel products, including hot and cold rolled sheets

and coils, galvanized sheet, electrical sheets, structural, railway products, plates, bars and

rods, stainless steel and other alloy steels. SAIL produces Iron and Steel at four integrated

plants and three special steel plants, located principally in the eastern and central religions of

India and situated closed to domestic source of three raw materials including the Company's

Iron Ore, limestone and dolomite mines.

SAIL'S wide range of long and flat steel products are much in demand in the domestic as well

as the international market. This vit. CMO encompasses a wide network of 38 branch offices

and 47 stockyards located in major cities and towns throughout India.

With technical and managerial expertise and known-how in steel making gained over decades,

SAIL's Consultancy Division (SAILCON) at New Delhi offers services and consultancy to

clients world-wide.

SAIL has a well-equipped Research and Development Center for Iron and Steel (RDCIS) at

Ranchi which helps to produce quality steel and develop new technologies for the steel

industry. Beside SAIL has its in-house Center for Engineering Technology (CET) Management

Training Institute (MTI) and Safety Organization at Ranch. Its captive mines are under the

control of the Raw Materials Division in Kolkata. The Environment Management Division and

Growth Division of SAIL operate from their headquarters in Kolkata. Almost all its plants and

major units are ISO certified.

Integrated Steel Plants :-

Bhilai Steel Plant (BSP) in Chhattishgarh.

Durgapur Steel Plant (DSP) in West Bengal.

Rourkela Steel Plant (RSP) in Orissa.

Bokaro Steel Plant (BSL) in Jharkhand.

IISCO steel plant (IIS) in west Bengal.

Special Steel Plants :-

Alloy Steel Plants (ASP) in West Bengal.

Salem Steel Plant (SSP) in Tamil Nadu.

Visveswaraya Iron and Steel Plant (VISL) in Karnataka.

Subsidiaries:-

Maharashtra Electro smelt Limited (MEL) in Maharashtra.

BACKGROUND & HISTORY OF SAIL :

A Rich Heritage:

The Precursor

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

industrialization 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.

Expanding Horizon (1959-1973)

Hindustan Steel Limited (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

plant were also transferred to Hindustan Steel. The registered office was originally in New

Delhi. It moved to Kolkata 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 1MT 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 1.58 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

1967, 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 in1968-69 and subsequently to 4MT in 1972-73.

SAIL Today

SAIL today is one of the largest industrial in India. Its strength has been the diversified range of

quality steel products catering to the domestic, as well as the export markets and a large pool

of technical and professional; expertise.

Having achieved the initial goal of laying the foundation for the industrial development of

the country. SAIL took up the new challenge of facing the era of liberalized economy and the

emerging competitive scenario in the Steel market on the eve of entering the new millennium,

SAIL launched its Financial and Business restructuring program. The strategy includes a

divestment of non-core activities, restructuring of marketing function and a focus on pruning

cost of operation. The goal for the company is to emerge as one of the lowest cost producer in

the global steel market.

PRODUCT MIX :

Product Wise

  Semis Blooms, Billets & Slabs    Long Products Structurals

Crane Rails

Bars, Rods & Rebars

Wire Rods  

  Flat Products HR Coils, Sheets & Skelp

Plates

CR Coils & Sheets

GC Sheets\ GP Sheets and Coils

Tinplates

Electrical Steel  

  Tubular Products   Pipes  

  Railway Products Rails

Wheels, Axles, Wheel Sets  

Plant Wise

  Bhilai Steel Plant Blooms, Billets & SlabsBeams

Channels, Angles,bars

wire rods (tmt, plain& ribbed)

plates, Rails & heavy structurals

Pig Iron, Chemicals & Fertilisers

  Bokaro Steel Plant HR Coils & Sheets

Plates

CR Coils & Sheets

GP Sheets & Coils/ GC Sheets

Pig Iron, Chemicals & Fertilisers

  Durgapur Steel Plant Blooms, Billets & Slabs

Joists, Channels, Angles

Bars, Rods & Rebars

Skelp

Wheels, Axles, Wheel Sets

Pig Iron, Chemicals & Fertilisers  

  Rourkela Steel Plant HR Coils

Plates

CR Coils & Sheets

GP Sheets/ GC Sheets

Tinplates

Electrical Steel

Pipes

Pig Iron, Chemicals & Fertilisers  

  Salem Steel Plant Stainless Steel

THE SEVEN C’S OF SAIL

Consistent Quality

Committed Delivery

Customized product

Competitive Price

Complaint Settlement

Contemporary Products

Culture of Customer Service

COMPANY PROFILE

BHILAI STEEL PLANT

BRIEF DESCRIPTION OF BHILAI STEEL PLANT

BRIEF HISTORY

Bhilai Steel Plant (BSP) is a unit of Steel Authority of India (SAIL). Bhilai Steel Plant is a

pulsating giant in the glorious Industrial context of India. It came into existence on 10th June

1957. BSP the functionary of SAIL is a symbol of lndo-Soviet Techno economic collaboration,

and is one of the first three integrated steel plant set up by the Government of India to build- up

a sound base for industrial growth of the country. The agreement was signed on 2nd February,

1955 for 1 MT production capacity; which rose to than 2.5 MT (1967). and then to 4 MT in

1988 production of Crude Steel Per year.

On 4th February 1959 the President, Dr. Rajendra Prasad dedicated Bhilai to the

Nation by inaugurating the Blast Furnace No. 1 for production. Since then Bhilai has never

looked back and has steadily grown and modernized day by day. Bhilai has all along been

giving special attention to the employment to the weaker section. Bhilai has contributed

significantly to meet the Iron & Steel requirements of the country.

The Steel Plant has 10 coke ovens batteries and 7 Blast Furnace. The Plant get

its requisition of raw materials and necessary resources by various adjoining centers. The Iron

ore is met from the captive mines of the plant which is situated at Dalil-Rajhara, the

mechanized iron ore mines 100 kms south from BSP. Lime stones also come from the manual

mines of Nadini about 25 kms to the North of the Plant. The need of Dolomite is fulfilled from

the queries of Hirri in Bilaspur District.

Steel plant requires various forms or energy, viz. electricity, fuel (solid, liquid &

gases). steam oxygen, compressed air. chilled water, air blast etc. At Bhilai the main source of

electricity is the CSEB grid from the NTPC korba Station, about 250 Kms. away. The Steel

Plant has have their own capacity of generating electricity of 36 MW and 74 MW by power

plant I & II respectively as the alternative source of power supply to meet emergency loads in

case of interruptions.

There exist and extensive communication system at the work which include Auto

Telephone Exchange dispatched Communication system, shop-floor loudspeaker system, gas

and fire signaling and blocking system of the plant rail transport facilities etc.

PLANT LAYOUT:

The unit or the plant has been laid in sequential formation according to technological

interrelationship so as to ensure un-interrupted flow of process material like coke. Slag etc

and to minimize the length of various inter plant connection utilities and services.

STRUCTURE & CAPACITY

Primary steel area:

AREA STRUCTURE PRODUCTS CAPACITY

Coke oven 10 Batteries +25MM Coke 3.303MT

SP I 2 Sintering machine Super flux sinters 2.04MT

SP II 3 Sintering machine 3 Sintering machine 3.137MT

SP III 1 Sintering machine 1 Sintering machine 3.19MT

B.Fcs 7 B.fcs Hot metal 4.08MT

Saleable pig iron 0.63MT

SMS I 4 Twin hearth furnaces Ingot steel 2.5MT

SMS II 3 LD Convertors Liquid steel 1.5MT

CCS 4 Single strand continuous Slabs 1.8MT

casting machines

1 Combi-caster &

1 four strand casting Blooms 0.24MT

machine For blooms .

Captive mines

Iron-Ore - Dalli-Rajhara Iron Ore Complex, 80 kms from Bhilai

Limestone - Nandini, 23 kms from Bhilai

Dolomite - Hirri, 150 kms from Bhilai

Coke Ovens

BATT NO. NO. OF OVENS

OVEN HEIGHT(M)

COAL HOLDING CAPACITY PER OVEN

(T)

USEFUL VOLUME

PER OVEN CU.M.

SP.HEAT CONSPN.KCAL/KG

1-8 65 4.3 16.8 21.6 625-675

9&10 67 7.0 32.0 41.6 625-675

Blast Furnaces 3 of 1033 Cu m capacity each 3 of 1719 Cu m capacity each 1 of 2355 Cu m capacity

Hot Metal Capacity : 4.70 MT / year

Steel Melting Shop

Steel-making through BOF, VAD/Ladle Furnace/RH-Degasser and Continuous casting route

3 converters of 110/130 T VAD unit, 2 RH degasser,2 Ladle furnace 4 Slab Casters, 1 bloom caster, 1 Combi caster

Annual Capacity: 1.425 MT Cast steel

Converter Shop :

3 BOF 110/130 T Convertors Secondary Refining facilities : 1 VAD unit, 2 RH degassers, 2 Ladle furnaces, 1

Desulphurisation Unit

Continuous Casting Shop: 4 Slab Casters, 1bloom caster, 1Combi caster

Steel-making through Twin Hearth Furnace (THF) route :

4 THFs of 250 T capacity each Annual capacity 2.5 MT ingot steel

Blooming & Billet Mill

14 pairs of recuperative soaking pits Capacity to produce 2.14 MT/year of blooms

Capacity to produce 1.50 MT/year of billets  

Rail & Structural Mill

Capacity - 7,50,000 T

Products

Rails - R52 Kg/m & R60 Kg/m ; UTS 880 N/mm2 rails as per IRST-12/96 specifications , Euronorms and international standards.

Thick web asymmetric rail Zu 1-60 Beams - 600,500,450,400,350,300 & 250. Channels - 400,300 & 250. Angles - 200 & 150. Crossing Sleeper. Crane Rails - KP80, 100,120 & 140. Bhilai is the sole supplier of the country's longest rail tracks of 260 metres.

Bhilai Rails

Largest producer and leading rail maker of the world. Four and a half decades of experience in rail making. Produced over 15 MT of rails; 2.7 lakh km in length. Indian Railways- World’s second largest rail company moves exclusively on Bhilai

rails. Bhilai rails are subjected to world’s highest traffic density and axle loads. Rails exported to 10 countries with exports to South Korea, New Zealand,

Argentina, Turkey, Iran, Egypt, Ghana, Bangladesh and Malaysia.

Technological Superiority

Steel from LD Convertor – Ladle furnace - RH Degasser – Concast route; achieving world best level of degassing/refining to less than 1.5 ppm of hydrogen in liquid steel in 100% of heats.

Capability to produce as rolled lengths of 80 meter and welded panels upto 260 meters .

High degree of Straightness due to world’s most advanced and Laser straightness measurement based end straightening machine.

World class tested rails passing through state of art online NDT equipment; Laser straightness measurement, Ultrasonic and eddy current testing machines

Computer controlled automatic rail handling system and automatic yard mapping for rail storage.

Computerised Rail Tracking system for collection and storage of all process and testing related data of each rail.

Bhilai Rails- Universally Certified

RDSO, Indian Railways

RITES Ltd ISO-9001-2000 certified by LRQA (Lloyds Register Quality Assurance) ISO 14000 certified by BIS Crown Agents, London General Superintendence Company, Geneva Lloyds Register Of Shipping Robert W Hunt & Company Overseas Merchandise Inspection Company, Tokyo Egyptian Railways Inspection Team Tuboscope Vetco Gmbh, Deutcheland

Bhilai’s Special Purpose Rails

Copper Molybdenum Corrosion resistant rails High yield strength/ UTS vanadium micro-alloyed rails High conductivity metro rails Copper-Chromium alloyed High strength Rails

Merchant Mill

Capacity - 5,00,000 Tonnes

Products

Plain Rounds : dia 28, 32, 36,40, 50,53, 56, 63 & 67 TMT Bars : 25,28, 32, 36, 40 & 45 Lt. Structurals :Channel 100 x 50, 75 x 40 Angles : 50 x 50 x 5 upwards to 90 x 90 x 10

* Customised product campaigns are being taken up for shorter durations in case of light structurals and rounds for compliance of smaller quantity orders as per committed delivery within the month.

Wire Rod Mill

Capacity - 4,20,000 T

Wire Rods (Plain, Electrode Quality & TMT) in 5.5, 6, 7, 8 & 10 mm plain and ribbed, and 12 mm plain in coil form

8, 10, and 12 mm TMT

Plate Mill

Capacity - 9,50,000 TPlates thickness - 8-120 mmWidth - 1500-3270 mmLength - 5-12.5 M

The modern Plate Mill rolls out heavy and medium plates, as well as those for pipe manufacturers. Plates of wide variety, in any required size, and strength, chemical and physical properties, can be produced here. It has capacity to produce high pressure, boiler quality and high tensile steels. Shipbuilding plates, conforming to Lloyds specifications, and pressure vessel boiler plates, conforming to various ASTM, ASME standards, have withstood the challenges of nature and time. Some of the unique features of the mill are on-line finishing facilities and off-line normalising facilities. Bhilai has the widest plate mill in the country, and it uses continuously cast slabs as input. Liquid steel produced under controlled conditions in the LD Converters is rinsed with argon gas to homogenise the composition as well as to remove non-metallic inclusions before continuous casting so as to ensure the production of high quality feedstock for the Plate Mill. As per customers' requirement or specifications, plates are normalised in a roller hearth normalising furnace.

New Products

To cater to the changing needs of the customers and to increase the market share, various new products were developed and commercialised through process improvement and Research and Development. The following grades were developed in 2008-09.

1. High Corrosion Resistant & Earthquake Resistant Fe-500 TMT Rebar in 40mm  2. Rockbolt TMT Fe600 in 32mm  3. 12mm Earthquake Resistant TMT Wire Rod in Fe-500 grade.  4. 36mm Earthquake Resistant TMT Rebar in Fe-500 grade 5. Cr-V alloyed 110 UTS Rail  6. Ultra-High strength SAIL MA 600 Plates  7. Low-C, Cu-bearing Structural Steel Plate for Corrosion Resistant Application 8. Thicker Plates (60mm) with ultra low temperature impact toughness at minus 50C

in High Tensile BSEN 10025 S355 NL grade  9. High Tensile Weather Resistant Plates in IRS M-41 (SAILCOR) grade for Indian

Railways in 8&10mm 10.High Tensile SBQ quality plates in NV E36 grade.  11.Cr-Mo alloyed IS 1570 Grade 53mm Round Bar for High Temperature

Application.  12.Thicker plates (115mm) in Structural Quality with guaranteed Ultrasonic

soundness .

The Cutting Edge Processes

Steel Making

Vacuum Arc Degassing: This unit ensures production of low sulphur steel with lower gas contents. Precise control of casting temperature, composition and improved steel cleanliness is achieved.

RH Degasser(2nos): A 130 T capacity RH (Ruhrstahi Heraus) Degassing Unit was installed mainly to remove hydrogen from rail steel. All rail heat produced in SMS-II have hydrogen level < 1.5 ppm.

Ladle Furnace(2nos): It is installed to process steel to reduce diversion due to chemistry and to process cold heats or return heats. The 130 T furnace also has benefits like reduction in tapping temperature of BOF, improvement in lining life of BOF, etc. It acts as a buffer between BOF & CCM for holding the heats, reduce consumption of ferro-alloys, carbonisers and deoxidiser and produce a cleaner steel.

Desulphurisation Unit : This has been installed to reduce hot metal sulphur for better steel-making

Finishing Mill

On line Ultrasonic testing machine in Plate Mill. - Mandatory on-line testing of API grade plates. - 100% scanning and edge testing of all plate surfaces.

Automatic thickness gauge and HAGC - Better quality assurance - Better dimensional and profile control - Improvement in yield by 2%.

Computerised tracking of plates in Plate Mill Plant-wide fiber optic cable networking

Environment Management

A conscious corporate citizen, BSP has accorded the highest priority to taking effective measures in the areas of resource conservation, pollution prevention, waste reduction and conversion of waste to wealth. Effective monitoring and analysis has ensured that BSPs compliance is well within the regulatory requirements.

ISO 14001 certification has been implemented in the entire Plant & township as well as in Dalli Mines. The plant has introduced environment friendly coal dust injection system in the Blast Furnaces, de-dusting system and electrostatic precipitators in other units. Besides, Clean Development Mechanisms for green house gas reduction, BSP has taken up the replacement of Ozone Depleting Substance CTC, aided by UNDP. The specific water consumption in BSP at 3.04 cu.m per tonne of crude steel in 2007-08 is one of the lowest in the country.

For the first time, BSP has earned Voluntary Emission Reduction (VER), a kind of carbon credit for two of its environment-friendly projects inside the Plant. The projects,

namely 'SP-3 waste heat recovery system' & 'Thyristerisation of last Furnace # 3 & 4 skip hoist electric supply' have been certified under VER by M/s. RINA, Italy. This will enable BSP to claim revenues for 9,74,743 Tonnes of Co2 Emission reductions till 2007-08, from the international VER market. These projects will also earn revenues on an average of 1,65,000 T of Co2 reductions every year till the completion of 10 year accounting period in each case.

Abiding by Corporate Responsibility for Environment Protection (CREP) guidelines & monitoring mechanism, Bhilai has also taken adequate steps to check fugitive emissions from Coke Ovens. It has installed Air cooled self sealing doors in Battery-3, resulting in significant reduction in door emissions. At Battery #7, water sealed AP caps and Pusher car with door cleaning mechanism has been introduced.

Green City

Contrary to the popular perception about industrial townships being dirty and polluted, a green canopy covers the township. A green-fingered population and a management aware of its obligations as a corporate citizen have come together for a massive tree-plantation drive over a period of years as a result of which afforestation sites and green expanses enrich the environment in mining and peripheral areas. There are five big gardens inside the plant and 15 gardens in the township. The cumulative plantation in the Works area and township is more than 30 lakhs while in the Mines, it is more than 22 lakhs. Spread over 167 acres, the sprawling Maitri Bagh that has the biggest musical fountain in the country, a zoo with 28 species of animals and birds, an artificial lake with boating facilities, a toy train etc., attracts over 5 lakh visitors every year.

The residential sectors of the steel city are kept clean and green by the Plant's Town Administration Department which also undertakes the civic amenities such as street lighting, cleaning and maintenance of the tree-lined carpeted roads. The water to the township is supplied from the Maroda water treatment plant having a capacity of over 30 million gallons per day. Water is distributed throughout the township through a system of underground reservoirs and overhead tanks.

Energy Consumption

Continuous monitoring

 

Apex Committee Inspection by HODs. Quarter review of Safety activities by ED(W) Fixing responsibility of line managers. Contractor workers safety - IPSS procedure enforcement, contractors' audit, safety

exhibitions Safety workshops

Regular inspections

Inspection of gas pipelines Inspection of structures, equipments and installations Risk Control Grading System implemented in Coke Ovens Battery 9 & 10, Blast

Furnace, SMS-1 and extended to BBM, Foundry Shop, and SMS-II.

Quality Assurance

ISO 9001 SEAL OF QUALITY

All major production units and marketable products in Bhilai Steel Plant are covered under ISO 9001:2000 Quality Management System. This includes manufacture of blast furnace coke and coal chemicals, production of hot metal and pig iron, steel making through twin hearth and basic oxygen processes, manufacture of steel slabs and blooms by continuous casting, and production of hot rolled steel blooms, billets and rails, structurals, plates, steel sections and wire rods.

Bhilai's products come with a complete assurance of quality.

This is achieved as a result of unrelenting attention and meticulous procedures at every stage of the process and upgrading of testing methods and equipment.

Right from selection of input material for steelmaking, the process parameters are kept under close control. Intensive checking of all quality parameters continues throughout the subsequent operations of casting, reheating and rolling. Express analysis with the help of sophisticated, direct-reading spectrograph and gas analyser ensures a narrow range of chemical composition. Intensive metallographic investigation with modern instruments like Scanning Electron Microscope, Image Analyser and Micro Hardness Tester is carried out to assess the quality of the product.

The key points of control are :

Chemical analysis of hot metal, liquid steel and final product. Inspection of surface and internal quality of the product by visual and ultrasonic

inspection. Monitoring and control of heating/reheating parameters. Dimensional and surface check during rolling and on finished product. Maintenance of cast identity throughout the process up to the end product

SERVICES & UTILITIES

BSP is an integrated Steel Plant which requires various forms of energy like electricity, Fuel

(solid, liquid and gaseous) stream, oxygen, compressed air, chilled water, air blast etc.

Electricity power is supplied by BESCL (Bhilai Electric Supply Company Limited) a

joint venture between National Thermal Power Corporation and SAIL from Korba 250 Km

away from Bhilai.

Water supply comes from a well constructed system of water works of the state

government - Tandula reservoirs, water from nearby rivers are brought to two huge water

reservoirs ( Maroda Tank 1 & 2) through a well laid canal, 60 km long from BSP.

The other utility gaseous liquid and solid fuels, chilled water, steam. Oxygen and

compressed air are provided- at Plant by centralized utility services.

There exists an extensive communication system at work place, which includes an

auto telephone exchange, dispatch communication system, gas and fire alarm signal, yeard

communication and automatic signaling and blocking system of plant, rail transport facility and

shop floor loudspeaker system.

Export section :

Bhilai Steel Plant has an export section to take care of the requirement of International Trade

Division (ITD). The export enquiry received by International Trade Division are sent over to

Bhilai for detail discussion. After the confirmation from Bhilai. International Trade Division

initiates action on commercial settlement and enter into a contract with the foreign buyer. The

work order then issued by International Trade Division is distributed to various agencies likes

Purchase, Finance and GM Services. Soon after subsequent rolling takes place. After

inspection is made the consignment is sent through railways to Vishakapatnam port for the

loading into ship. In case of export to Nepal, The consignment is moved by wagon either to

Patna, Kanpur or Bhilai for onward dispatch to the buyer in Nepal.

THE QUALITY POLICY OF BSP

Attaining market leadership through enhancing customer satisfaction.

Achieving continual improvement in productivity, quality and salability of our products.

Active involvement of all our people in achieving our goals, objective and targets.

Adherence to a quality management system based on ISO :9001:2000 and its periodic

review for continued effectiveness.

ORGANIZATIONAL OBJECTIVE

To enhance customer satisfaction through :-

Improvement in productivity ad product quality.

Skill enhancement of our people by competence, commitment and culture building.

Production as per Customer Requirement.

ENVIRONMENT POLICY

Bhilai Steel Plant committed to protect environment and shall strive to :

1. Introduce sound environmental management practices for minimizing pollution and its impact on air. water and land.

2. Conduct operations in an environmentally responsible manner for complying with legislation and regulations related to its environmental aspects.

3. Conserve and optimally utilize raw materials. energy. water and other resources.

4. Minimize waste generation and promote its recovery. Recycling and re-use.

5. Achieve continual improvement in environmental performance by setting and reviewing the objectives and targets periodically.

6. Enhance environmental awareness amongst employees and interested parties.

7. Communicate environmental policy to the persons working for or on behalf of the

organization and make it available to public on demand.

PRODUCT PROFILE

Bhilai offers a rich and varied product mix to the domestic and international market by different

ways. They are divided into two categories, which is

PRIME PRODUCTS: These are the products which are intentionally produces

Sale and to meet the requirement of the customers.

For eg. Blooms, Billets, Channels, Angles, round Steel bars, Wire rod, Rail, Plate etc.

SECONDARY PRODUCTS:

These are the defected or rejected material. Due to the improper mixing of chemical

Components or due to some lack in meeting customer requirement. Scrap generated inside

Bhilai Steel Plant is also termed as Secondary Products.

For eg. - Rejected slab, iron scrap, steel scrap, defective heavy blooms, defective billet

cutting, rails cutting, and slag.

Secondary products section started functioning after the commencing of Bhilai Steel Plant. The

secondary product section of the marketing department is solely responsible for the selling of

secondary products and by-products of BSP.

All the defective or rejected items of this department except the rejected defective plates,

sells scrap.

WHAT ARE SECONDARY PRODUCTS ?

In the cause of manufacturing process, in every stage of production, always there will be certain

Percentage of products which do not confirm to the standard quality, size and specification.

Such products are termed as ‘Secondary Products’. Moreover, while shaping the prime

products, both end and sides are cut. These cutting are also categorized as ‘Secondary

Product’ in Bhilai Steel Plant as they are re-rollable.

Following items are falls under the category of Secondary Products.

Defective heavy blooms

Defective Billets cuttings

Rejected Slabs

Plate Mill side shearing

Defective Plates

Rails Cuttings

Rod Cuttings

UTILIZATION OF SECONDARY PRODUCTS:

The secondary products can be utilized in two ways:

1. By re-rolling of secondary products.

2. . By selling secondary products

PRODUCTS OF BHILAI STEEL PLANT

Shop Products Annual Product Dimension Width Length End use / consumers

Capacity (Tonnes)

range (mm)/ Profile range (mm)

(metre)

Rail & Structural Mill   

Rails

 

Heavy Structurals

 

 

 

 

 Crane Rails

Crossing sleepers

750000 45Kg, 52Kg & 60 Kg Rails

Beam600x210,500x180450x150, 400,350,300x140250x125Channel400x100, 300x90250x82Angle150x150, 200x200

 

CR80,100 & 120

  13, 26, 65, 130 & 260  

Indian Railways, Export

 

Infrastructure Projects

 

 

 

 

 

Cranes

Broad gauge sleepersMerchant Mill

Lt. Structurals

 

 TMT

Round

5,00,000 Angle 50x50, 65x6570x70, 75x7580x80, 90x90Channel75x40, 100x50TMT20, 25, 28, 32, 36, 40,45Rounds  (Plain)28, 30, 32, 36, 40, 50, 53, 56,63, 67

    Engineering and Infrastructure Projects

Wire Rod Mill

Wire Rods(Plain)Wire Rods (TMT)

4,00,000 5.5, 6, 7, 88, 10, 12

    Electordes ManufactureInfrastructure Projects

 Plate Mill Plates 9,50,000 8 – 160 1500 – 3300

4.5 - 15.0 Boilers, Defence ,Railways, Ship building, LPG cylinders, Irrigation, Export

Semis Bloom, NWS  Slab & Billets from BBMHC Bloom from CCSSlab from CCS

5,53,000 Billets902 , 1002 , 1102 Blooms1502 , 3202

    Re-rollers

Pig Iron           FoundryBy Products Coal Chemicals

 

 

 

Processed Slag

  Ammonium Sulphate (Fertiliser)- Brand Name -RAJA

Tar products,(Pitch, Napthalene, Creosote Oil Road Tar,Anthracene oil, Dephenolised oil, PCM etc.),

Benzol products (NG Benzene, Toulene, Xylene,Solvent oil, Heavy  Benzol etc.)

Granulated slag from CHSG Plants & SGP for cement manufacture

Special Products of SAIL-Bhilai Steel Plant and their applications

Long Products

Product ApplicationRail (Carbon-Manganese; 90 Kg/mm2 UTS)

Railway Tracks all over the country

High YS/UTS Rail (V/Nb Micro-alloyed)

Heavy haulage, high density railway tracks

Corrosion Resistant Rail Corrosion prone regions, mainly coastal areasCr-V alloyed High Strength (100 Kg/mm2 UTS) Rail

Heavy haulage, high density railway tracks; developed for Dedicated Freight Corridor

Thick Web Asymmetric Rail Points & Crossings in Railway trackHigh Conductivity Rail (Rimming quality)

High conductivity rail or ‘Third Rail’ for Metro Rail, made through Rimming process

Crane Rail Crane rails in CR-80/CR-100/CR-120 sections, used for tracks of different types of cranes

EQR TMT Bar & Wire Rod (8, 10, 12, 25, 28, 32, 36 & 40mm)

Construction of high-rise buildings, bridges and structures in seismic prone areas

HCR TMT Bar & Wire Rod (8, 10, 12, 25, 28, 32, 36 & 40mm)

Construction of high-rise buildings, bridges and structures in corrosion prone areas

HCR EQR TMT Bar & Wire Rod (8, 10, 12, 25, 28, 32, 36 & 40mm)

Construction of high-rise buildings, bridges and structures in areas susceptible to both seismic activities and also corrosion

Rimming grade EQ Wire Rod Production of low current consuming Arc Welding Electrodes

Drawing quality Wire Rod (SWR-10, SWR-14)

Drawing of Wire Rods into thinner gauge wires for different applications

SAIL MA 410 structurals For construction sector, requiring higher tensile strength

SAIL TOWER Semis For re-rolling into high strength structurals, for construction of Transmission Line Towers

Introduction to SMS-2

SMS i.e. steel making shop is that part of the plant where steel making furnace(s) is located and where steel is made and cast into ingots.Generally SMS is supposed to carry out the following functions:

1. Preparation and storage of raw materials required for the entire shop so that these are readily available during te operation flow .orders for the materials must beplaced well in advance to avoid any delays.

2. Charging and melting and subsequent refining of the charge to the desired chemical analysis.

3. Deoxidation of steel ,either inside and/or outside the furnace,addition of alloying elements,if any,to obtain desired chemical composition.

4. Tapping the refined and finished steel from the furnace into a ladle ;ladle additions to be made while tapping.

5. Then, send to the secondary refining unit,if required. 6. And ultimately after casting into moulds ,sent to various mills viz. plate

mills ,rail mill,rolling mill etc.

.

LAYOUT OF SMS-2

Project report

IntroductionSteel is not any specific product it is essentially a malleable alloy of iron and one or more of

other element like carbon ,chromium , nickel,silicon, vanadium,tungsten, or any other active

element. The chemical composition of steel broadly divide them into two major groups:

1. Plain carbon steel :plain carbon steel is broadly sub-divided into four catogories based

on the percentage of carbon

Soft or low carbon steel Upto .15% C

Mild steel .15% to .35% C

Medium carbon steel .35%. to 65%c

High carbon .65% to 1.75%C

2. Alloy steel: Theseare broadly subdivided into three groups on the basis of the total

alloying elements present

Low alloy steels Upto 5% aloying elements

Medium alloy steels 5-10% total alloying

High alloy steels Above 10%

The plain carbon steel are essentially alloys of fe and carbon only whereas ,if one or

more of elements other than carbon are added to steel in significant amount to ensure

specific better properties such as better mechanical strength, ductility,electrical and

magnetic properties, corrosion resistance band so on it is known as alloy steel.

Steel may contain many other elements such as Al, Si,Mn,S,P etc which are not added

specifically for any specific purpose but are inevitably present because of their

association in the process of iron and steel making. These are known as the impurities

in steel. Every attempt is made to minimize them during the process of steelmaking but

such efforts are costly and special techniques are required for decreasing their contents

below a certain level in the case of each element .For cheaper variety of steels therefore

their contents at high level are tolerated .these tolerable limits of impurities are

considered as ‘safe limits’ and the impurity levels are maintained below their safe limits.

For example for ordinary steels sulphur content is upto to .05% are tolerable whereas

for several special steel the limit goes on decreasing to as low as .005% or even lower.

For most high quality steel now the total impurity level acceptable is below 100 ppm and

the aim is 45ppm.

Various grades of steel

1. Mild steel.

2. High tensile steel.

3. Boiler quality.

4. Rail steel.

5. Other steels like DMR, SAIL-HITEN

BLAST FURNACE

The Blast furnace iron making process basically consists of the conversion of iron oxide to iron in liquid form. This requires reductant for reduction of iron oxide and heat for the above reduction reaction to take place and for melting the products of smelting.The primary source to fulfill both these requirements is carbon (in the form of coke), which shares major portion of cost of hot metal production.The blast furnace is a vertical counter-current heat exchanger as well as a chemical reactor in which burden material charged from the top descend downward and the gases generated at the tuyere level ascend upward.The inside profile of the furnace from top to bottom is termed furnace throat, shaft, belly, bosh and hearth. The throat is the top part of the furnace and includes the installation necessary for charging coke and burden materials and drawing off the top gases. The top gas containing the flue dust is routed from the furnace top to the gas purifiers and then to the consumption zones. The profile of the furnace widens in the shaft that follows. The widening of the furnace chamber from top to bottom is necessary to avoid hanging and scaffolding of the burden in the blast furnace when they expand during heating.The height of the shaft is about 3/5 of the total height of the furnace. The shaft is followed by the belly in the bosh below this, the profile again narrows, as this is the part of the furnace where the stock column starts to melt and volume of the furnace can be reduced. The hearth is the lower cylindrical part of the furnace where the fluid slag and the hot metal accumulate. Arranged in the upper part of the hearth are water-cooled tuyeres made of copper. The hot air for combustion is injected through these into the blast furnace. Hot metal is tapped through the tap hole, which is opened by power driven drills into a train of ladles kept below the runner of the cast house. Slag comes along with the metal and is skimmed off with the help of skimmer plate towards slag runner and is collected in slag thimbles. The tap hole is tightly sealed with a mud gun after tapping process is complete.Raw material (ore, sinter, coke) are screened before being charged into the blast furnace through conveyors or skip. Air for combustion in the blast furnace is blown from turbo blowers which are preheated in hot blast stoves to temperatures around 1300⁰C, which is then blown through tuyers into the blast furnace. Each blast furnace is equipped with two or more stoves which operate alternatively.Preheating of air helps in reducing fuel consumption in the furnace.ReactionFrom top to bottom of the furnace the following process occurs :-Drying, preheating, ejection of hydrate water-Indirect reduction-Direct reduction-Melting

  In the top third of the shaft, gas delivers its heat so that the charging materials are preheated and dried.When a temperature of 400⁰C to 500⁰C is reached, the water which was fixed with the burden is ejected.Indirect reduction by carbon monoxide occurs below 1000⁰C. At temperatures above 1000⁰C, iron oxide not yet reduced into iron is directly reduced. After melting, the reduction process is completed as hot metal flows through layers of coke.Hot metal produced in the blast furnace is sent to Basic oxygen Furnace for steel making or to Pig casting machines for pig iron casting in ladles.

Pre-treatme nt of Hot metal

Hot metal from blast furnaces is treated to remove undesired elements like sulphur, silicon or phosphorous before being transformed to steel. Desulphurising agents are applied to reduce sulphur content of the metal. 

 

Hot metal desulphurisation: magnesium calciumcarbide co-injection

On the road to steel making the very first step is to pour out hot metal (pig iron-product of blast

furnace) from the mixer which is used to homogenise the temperature and composition of the

hot metal.

Hot metal usually contains a lot of detrimental impurities mentioned above (S,Si,P,Mn,C etc).

However ,elimination of sulphur and phosphorus is not possible simultaneously for the reason

elimination of sulphur requires :

1.High temperature

2.High basicity

3.low oxidizing atmosphere.

Whereas phosphorus requires high temperature , high basicity & high oxidizing

atmosphere.Hence introduction of desulphurisation unit was established before the primary

steelmaking unit(B.O.F).

The evolution of external hot metal desulphurisation has been driven by the ever-increasing consumer demand for higher quality steels. Currently, deep co-injection of magnesium and lime is a proven successful method of desulphurising

hot metal that offers steel producers a reliable, repeatable and economical means of meeting their production requirements. Over the past few decades the demand for steel around the world has been increasing at a rapid rate, coupled with an increase in steel quality. Steel producers are required to maximise throughput, minimise production outages and maintain high quality standards while all the time minimising costs. One major technique for improving the quality of steel is to reduce its sulphur

content. Sulphur is one of the most detrimental impurities in the steelmaking process, affecting both internal and surface quality. Unlike other impurities that are removed from the hot metal by oxidation in the converter, the most economic method of removing sulphur from the hot metal is by reduction before being charged into the converter. There are a variety of methods that have been developed but all require a reagent

and a method of mixing. The differences between the technologies used are the properties of the reagents,

the reagent effectiveness to remove sulphur and the effectiveness of the mixing method used to get the reagent into solution.

Reagents

Although the methods of addition may be different, reagents currently used are lime , calcium carbide(considered best as it has best affinity with O2 & S) and magnesium(Mg-coke-97:3 as Mg isexplosive in nature).

Lime Lime has always played a role in steelmaking desulphurisation. Its low cost and availability make it an attractive consumable, however, there are some critical disadvantages. During the desulphurisation process lime particles are continuously being covered by two precipitates: calcium sulphide (CaS) and calcium silicate (CaSiO4). These compounds impede the desulphurisation reaction by surrounding the lime (CaO) and forming thick barriers at the lime – hot metal interface . In order to reduce this growth, the grain size of the lime must be restricted to 45μm maximum. Another method of avoiding the retardation of the reaction is to keep the hot

metal temperature high in order .But nowadays lime is not used for sulphur elimination ,however used with MgO for basicity accomplishment which is a prime requirement in desulphurization process.

CALCIUMCARBIDE:Once the most dominant of all desulphurising reagents, calcium carbide is now less prevalent. Complicated material handling issues as well as stringent environmental requirements associated with the disposal of slag have negatively influenced its use. Calcium carbide is also subject to precipitate layer formation similar to lime, which impedes the desulphurisation reaction.CaC2 + FeS = CaS2 + Fe

MAGNISIUM:Although some earlier desulphurisation techniques involved mono-injection of magnesium, these practices have become less common due to the violence of the reaction and the relatively complicated equipment required. Magnesium is the only one of the three desulphurisation reagents that is soluble in hot metal and reacts with the sulphur in solution. Typical magnesium desulphurisation reactions are as follows:

Mg(s) → Mg(g) Mg(g) → Mg

Mg + S → MgS(s) (FeS + Mg(g) = Fe + MgS)

Due to its relative low boiling point (1,090°C), magnesium vapourises as it enters the hot metal. This vapour is under high pressure which is directly related to solubility. Once in the ladle, the magnesium vapour forms bubbles which rise through the hot metal, dissolve and react with the sulphur in solution, forming magnesium sulphide (MgS). The MgS then floats to the top of the ladle and settles in the slag layer, which is later skimmed off. The lime that is injected with the

magnesium assists in dissolution by reducing the diameter of the bubbles as well as providing precipitation sites for the MgS. Magnesium has a high affinity for both oxygen and sulphur. Unlike lime, magnesium is not accompanied by oxygen when it is introduced to the hot metal, therefore, it can rapidly react with sulphur to form magnesium sulphide. Magnesium in solution that does not react with sulphur may also react with any oxygen in the hot metal, so removing excess oxygen.

.

Reagent ability to remove sulphur: It is important to realise that all reagents are not equal when it comes to the ability to remove sulphur. Magnesium, although more expensive, has approximately 20 times the capacity for removing sulphur as lime. Calcium carbide has eight more times the potential to remove sulphur than lime; however, if injected into hot metal on its own it must be blended with volatiles in order to increase bath agitation.

Blended injection: The injection of pre-blended magnesium/lime or magnesium/calcium carbide combinations has also become less widespread. By blending reagents prior to treatment steelmakers sacrifice the ability to adjust individual injection rates of materials. Also, blended reagents are prone to material segregation in transport and storage vessels.Therefore, reagents( CaC2 &Mg) are injected in a specific ratio during the process of desulphurization according to grade of steel to be prepared. Desulphurisation if done ,aim is to obtain a product with sulphur content less than 10. Reagent ratio (1CaO/8CaC2/20Mg) ` Mg unit consumption 0.6 kg-Mg/t HM ` Co-injection ratio (Mg/CaO) 1: 4 Co-injection ratio (Mg/CaC 2) -: 1:5

DATA AQUISITION

Sno.

HM wt

HM tem

p

StartS

AimS

FinalS

MgChar

t

Mginjecte

d

CaC2

Chart

CaC2inject

ed

1 120 1319 45 10 9 41 40 205 2072 120 1320 45 10 13 41 40 205 2023 120 1316 35 10 8 41 40 205 2084 120 1316 35 10 8 32 31 160 1635 120 1288 35 10 10 32 30 160 1876 120 1304 35 10 8 32 32 160 1637 120 1304 35 10 10 32 31 160 163

Slag removal

Sulphur-rich slag generated during the process is usually removed immediately after completion of the reagent injection. The most common method is to tilt the ladle and rake the slag off with the help of a slag skimming machine. Typically, the facility is designed so that the operator can have a clear line of vision of the skimming process while inside the operator control room . This keeps the operator safe from excess heat and airborne dust exposure. Depending on the heat size and customer requirements, additional slag skimming process equipment such as thermal-imaging cameras, slag bubblers and slag coagulant injectors can be added to enhance the operation.

Environmental control

Both reagent injection and slag skimming procedures generate fumes which have to be extracted and de-dusted prior to their release into the environment. Danieli Corus believes that the best fume collection device is an environmental enclosure. This structure envelops the entire desulphurisation and slag skimming processes, virtually guaranteeing that no fumes escape into the steel shop. In applications where there are either physical limitations or operational requirements that prevent the use of an environmental enclosure, fume hoods can be installed to capture fumes during both reagent injection and slag skimming. The captured fumes are typically cleaned in a pulse jet type baghouse, designed for metallurgical applications

Temperature loss The sensible heat of the hot metal is one of the main sources of energy in the steelmaking process, hence loss of temperature is a major operational cost of the desulphurisation process. The three primary sources of heat loss are radiation from the surface of the hot metal, addition of cold reagents and the introduction of cold injection lances or stirring impellers into the hot metal. The largest temperature loss occurs during injection or stirring operations rather than skimming. As a supplier of co-injection systems, Danieli Corus can guarantee a maximum

temperature loss of 1.2°C per minute during injection. Considering an injection time of 5-10 minutes, plus other losses due to operations such as skimming, the overall temperature loss of co-injection operation can range from 10 to 20°C. The design figures for the KR process temperature loss are 25 to 50°C. Most

operations can manage to keep the temperature loss less than 30°C by using lime instead of calcium carbide. The reasons for the higher temperature loss with the KR process are larger hot metal surface area during stirring, the addition of larger quantities of reagent and large size of stirring impellers. It is predicted that 10°C temperature loss/tHM results in a 0.88% decrease in the scrap charge to the converter. This decrease in scrap would require more hot metal charged into the converter in order to maintain production rate. This increase in hot metal consumption would result in a ¥2.14/tHM cost increase. Predictions can be made using electrical and chemical reheating models to estimate the cost of recovering the energy lost due to the drop in hot metal temperature. Each of these methods adds ¥1.39/tHM and ¥2.74/tHM, respectively for a 10°C gain. Co-injection temperature loss 20°C .

Although more expensive on a weight basis, magnesium has the highest potential for removing sulphur from hot metal. This increased efficiency allows steelmakers to use less reagent which translates into cost savings that are realised further down the processing chain.This overall cost savings, combined with the adaptability and

versatility of the facility layout make co-injection a superior choice for the desulphurisation of hot metal.This comparison does not include other cost parameters such as slag

disposal and capital cost which also tend to favour co-injection.

Additional -CO injectionProcess control Reagent addition is highly controlled, quick, reliable and predictable. The variable orifice injection control system developed by Danieli Corus is critical to the precise control of reagent injection (see Figure 5). The functionality of the system is based on the control of three set points: nitrogen flow, dispenser pressure and dispenser weight.By maintaining constant nitrogen flow and dispenser pressure, the

variable orifice valve can fluctuate based on the weight change in the dispenser to ensure that the required amount of reagent is being added to the supply line. This allows the operator to change flow rates between heats by adjusting the position of the variable orifice valve via the PLC control system and so maximise sulphur removal and conserve reagent use.The principal advantages of the system are as follows:` Superior control of reagent flow in terms of density and velocity, which substantially reduces plugging of injection lances` Possibility to change reagent flow rate in a relatively wide range via a computer terminal` Precise control of reagent injection rate and injection ratioWith mechanical stirring, the optimisation of process depends on

much more than the addition of the reagent. Rotation speed, immersion depth of the impeller as well as eccentricity of the impeller all have a critical effect on the rate of desulphurisation of the hot metal.

Refractory costs and wear Ladle refractory wear is related to the amount of time that the hot metal stays in the transfer ladle. The short treatment times experienced with co-injection allows for faster processing which translates into more tonnes per ladle lining. With mechanical stirring, a substantial amount of freeboard is required to account for the hot metal that is displaced by the impeller as well as the increased hot metal height in the transfer ladle due to the vortex created by stirring. To account for this level change, steelmakers have either to decrease the amount of hot metal in their transfer ladles, which decreases throughput, or increase the size of the transfer ladle, which means a retrofitting cost and higher refractory costs.

39

With co-injection, the reagent addition occurs sub-surface. Injection rates and speeds are customised to meet the requirements of each specific installation so that volatility on the surface of the hot metal is minimal and transfer ladle freeboard requirements kept to a minimum.

Installation and retrofitting Co-Injection desulphurisation facilities have the flexibility and adaptability to accommodate for limited space in existing steel plants. Because the reagents are pneumatically transported to the facility, stations can be designed to fit within tight space requirements by locating reagent silos up to 100m away from the station. Mechanical stirring facilities are limited in their flexibility because of their large impeller size. In plants with large ladle capacities, increased vertical height of the building may be required to ensure clearance on the vertical movement of the larger impeller.

ConclusionsElevated customer quality requirements continue to drive steelmakers to refine their processes to make better and cleaner steel. Reducing sulphur levels in hot metal is one of the critical steps to satisfying this demand. With the desulphurisation process, as in many other areas of steelmaking, there is more than one approach to achieve the same end result. Limiting constraints such as space, budgets, availability of consumables, environmental requirements, and operational costs are all factors to be considered. The final goal, however, is to purchase the most advanced technology with the best return on investment and operational costs. Deep co-injection of magnesium and lime is commonly used worldwide because it provides cost-effective desulphurisation of hot metal. Although it may use more expensive reagents, the process uses those reagents effectively and efficiently. The end result is a versatile, consistent and economical method of removing sulphur from hot metal

40

 

Primary steelmaking consists of refining of hot metal or scrap +hot metal to steel in converter . The objective is to refine hot metal to the nearly desired chemistry. a) Types of converter steelmaking

41

• In converter steelmaking pure oxygen is blown from top through a water cooled lance fitted with multi-hole nozzles. This technology of refining of hot metal is called top blown steelmaking. • In another version of converter steelmaking oxygen is blown from top and bath is gas stirred through the bottom. These are called combined top blowing and bottom stirred processes. • In some converters, 𝑂𝑂2 is blown from top and bottom and these processes are called top and bottom blowing, Duplex blowing or hybrid blowing. • In some converters oxygen is blown through the bottom and the process is bottom blown converter. This variant is not popular amongst steelmakers • Typically converter steelmaking technology allows to tap liquid steel in approximately every 50 to 60 minutes with specified steel chemistry and 500-1000ppm dissolved oxygen. • Typically oxygen blowing time is independent of converter capacity i.e. O2 is blown for 15 to 20 minutes irrespective of the converter capacity

(a)Top blown steelmaking (b) Combined top and bottom blowing (c) Bottom blowing

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It is important to note that in all different types of converter steelmaking practices, a pear shaped vessel is used and blast furnace hot metal is refined to plain carbon steel. Some amount of scrap is also used.

Principle chemical reactions

Hot metal contains C ~ 3.5 to 4%, Si ~ 0.6 to 1%, Mn~ 0.6 to 0.8% P ~ 0.1 to 0.2%. Oxygen is blown from top and the following reactions occur:

[Fe]+[O]= (FeO) [C]+[O]= {CO} [Si]+2[O]= (SiO2) [Mn]+[O]= (MnO) 2[P]+5[O]= (P2O5) [C]+(FeO)= {CO}+[Fe] (Fe)+ (MnO)= (FeO)+[Mn] 7Note the following: • No heat is supplied from outside. The heat produced due to chemical reactions is sufficient enough to raise the temperature of hot metal from around 1250℃ to 1300℃ to molten steel tapping temperature of 1600℃ to1650℃ . • Except carbon which is removed as a gaseous phase rest all other elements form slag. Slag formation of desired chemistry and

43

physicochemical properties is vital for the successful operation of converter steelmaking technology.

1.HOT METAL CHARGING

44

2.BLOWING

3.SCRAP OR FERRO ALLOY ADDITION

45

4.DESLAGGING.

5.TAPPING

46

BASIC OXYGEN FURNACE The basic oxygen process is the most common process for producing steel. The basic oxygen furnace (LD convertor) is a pear shaped vessel lined inside with refractory bricks. The vessel lining consists of tar bonded dolomite /magnesia carbon bricks or other refractories. The vessel can be rotated 360 o on its axis. Oxygen is blown into the vessel with the help of water cooled lance.The 'heat' begins with the addition of scrap into the slightly tilted convertor, hot metal is then added after straightening the convertor, Oxygen is blown into the bath through the lance .The necessary fluxes are added during blowing .Flux addition is done automatically and precisely through bunkers situated above the converters. A sample is taken after blowing for 16-18 minutes and temperature is measured using a thermocouple. The steel is tapped by tilting the convertor to the tapping side and alloying elements are added via chutes while metal is being tapped The convertor is tilted to the charging side in order to remove the floating slag .

During blowing operation, oxygen oxidises iron into iron oxide and carbon into carbonmonoxide. The iron oxide immediately transfers the oxygen to the tramp elements. The center of the reaction has temperatures of around 2000C to 2500C .The development of carbon monoxide during refining process promotes agitation within the molten bath. The reaction of the tramp elements with the oxygen and the iron oxide developed in the center of reaction leads to formation of reactive slag. As blowing continues, there is a continuous decrease of carbon, phosphorous, manganese and silicon within the melt. Phosphorous is removed by inducing early slag formation by adding powder lime with oxygen. The refining process is completed when the desired carbon content is attained. MICRO ALLOY ADDITION:

The addition of microalloying elements to steels has gained in importance in recent years and is often characteristic of modern steels. The use of microalloys is expected to further increase as new steels are developed.The term "microalloy" means, that the content of these elements is rather low and usually below 0.1 wt %. Unlike trace elements, which are usually undesirable, microalloys are added intentionally to improve steel properties. Besides the obvious difference in the magnitude of the alloy content between alloying and microalloying elements, also their different metallurgical effects are usually characteristic: Whilst alloying elements predominately

47

affect the matrix of steel, microalloying elements nearly always influence the microstructure via the precipitation of a second phase besides a solute drag effect.Requirements in weldability, formability and fracture toughness demand a low level of non-metallic inclusions (oxides and sulphides) preferably with a globular form of any remaining inclusions. Thus low oxygen and sulphur contents are a prerequisite in modern steels. Furthermore, deoxidation by aluminium is standard practice for the removal of oxides from liquid steel. Aluminium remaining after solidification in the steel and not combined as alumina will form aluminium nitrides. The grain refining effect of this classical microalloy precipitate has been established for over 50 years. Also other microalloy additions such as calcium or rare earth elements, are well known for their effect on sulphide shape control.In addition to these elements which affect non-metallic inclusions, several carbide and nitride forming elements, alone or in combination, have had a strong influence on steel development since the 1960ís.The chemical elements titanium, vanadium and niobium are very effective as microalloys in steel, influencing the microstructure by both, a solute drag effect and the formation of nitrides and carbides. Since the solubility product and the physical properties of each element and each compound are different, there exist characteristic differences which cause each of these elements to have specific merits:

Titanium forms nitrides, which are stable at high temperatures and these titanium nitrides provide control of the austenite grain size at the reheating temperature before hot working and also in the weldment, in particular in the heat affected zone close to the fusion boundary. The elimination of free nitrogen due to the formation of TiN is positive for the toughness and indirectly makes niobium more effective. Furthermore, the influence of titanium on sulphide shape control had been widely used at a time, when the production of a low sulphur content was not standard.

Vanadium forms almost no austenite precipitates and is plentifully available for precipitation hardening during or after the g / a transformation. Even though the specific efficiency of vanadium compounds is comparably low, the high volume fraction of fine precipitates compensates for this, especially in steels with a relatively high carbon content.

48

Niobium is the most effective microalloy for grain refinement by controlling the austenite grain size during the reheating processes for heat treatments like normalising, quenching or carburising, acting additionally to the traditional AlN technology. Furthermore it has an outstanding status in retarding recrystallisation during austenite processing via thermomechanical rolling, resulting in grain refinement, which cannot be obtained by any heat treatment process. Other outstanding effects of niobium, such as lowering the g / a transformation temperature by a solute drag effect or the effective precipitation hardening potential can be used only to a certain extent owing to its limited solution in austenite.As a result, the combined usage of microalloys is often the optimum solution.

ADDITION OF SYNTHETIC SLAG We also have with us rich industry experience in successfully handling the requirements of Synthetic Slag Material. Its usage is very detrimental in the quality of steel as its processing can lead to harmful reversion of P, S and other unwanted oxides. These slag containers interact with steel in a balanced way, thus assisting in maintaining proper equilibrium with Steel. Other than this, it helps in absorbing inclusions as well as impurities, thus helping in producing a cleaner as well as better quality steel.

 Features:  It adjusts toxicity of Slag.It lowers melting temperature of slag. It helps in increasing its fluidity.It helps in absorbing inclusions and impurities, thus producing cleaner steel.

 

49

DATA ACQUISITION

Hot metal analysis Bath analysis

Sno. Si Mn P S C Mn P S1 0.76 0.18 0.13 0.019 0.15 0.13 0.019 0.0102 0.79 0.19 0.13 0.022 0.12 0.12 0.023 .0093 0.76 0.19 0.13 0.021 0.29 0.11 .018 0.0104 0.74 0.2 0.14 0.018 0.17 0.11 0.019 0.0155 0.7 0.19 0.13 0.016 0.1 0.12 0.026 0.0116 0.76 0.19 0.14 0.026 0.11 0.12 0.020 0.0107. 0.72 0.17 0.14 0.020 0.11 0.13 0.024 0.012

 

50

 

SECONDARY STEELMAKING

Objective

The objective of secondary steelmaking is to make the steel of desired chemistry and cleanliness by performing the following treatments in “Ladle”:

a) To stir the molten steel by purging inert gas through the bottom of the ladle.

b) To inject slag forming powder either through a lance for further refining

c) To produce clean steel either by removing inclusions or modify them by suitable injecting material

d) To carry-out deoxidation and degassing.

Secondary steelmaking in ladles has become an integral part of steelmaking. Ladles have additional heating facility and are called Ladle furnaces (LF).

There are several practices adopted for degassing, like vacuum tank degasser, stream degassing and recirculation degassing. In recirculation degassing steel is made to flow from the ladle into a separate degassing chamber and then returned after exposure to the vacuum. In one of the recirculation degassing practice metal

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circulation is achieved by dipping the degassing vessel into the ladle, the liquid steel is raised into the vessel, degassed and returned into the ladle.

RH Degasser -In another practice a refractory lined vessel is equipped with two legs (called snorkels) for dipping into the ladle containing molten steel. Pressure is reduced and argon gas is passed into one of the snorkel, thereby molten steel is raised into the vessel and recirculates back into the ladle through the other snorkel.

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Advantages and economy:

Increases in productivity of the steel plant Shortening of the tap to tap time of the melting unit Savings on primary energy and utilities Use of low cost charge material as well as ferro alloys Consistent steel quality from heat to heat Production of ultra clean steel Development of new steel qualities low maintenance cost Improved co-ordination of all units involved in the production

sequence Better working conditions for the operating personnel.

Various grades of steel that are produced by the above mentioned processes are as follows :- with their respective chemisty.

1. Mild steel: Typical Chemistry For Mild Steel:

%C = 0.12 – 0.18, %Mn = 0.70 – 1.0,%P = 0.030max, %S = 0.030max,%Si = 0.15 – 0.25, % Al = 0.015 - 0.025100 to 150Kg Petro coke, 1800 to 2000Kg SiMn, 100 to 150Kg FeSi

30o 50Kg Al are added to ladle during Tapping

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2.Rail steel

Typical Chemistry For Rail Steel:%C = 0.67 – 0.69, %Mn = 1.10 – 1.15,%P = 0.025max, %S = 0.020max,%Si = 0.15 – 0.25, % Al = 0.010max.

750Kg Petro coke 2200Kg SiMn, 300 to 500Kg Synthetic Slag 700Kg Lime are added to ladle during tapping.

3.Boiler quality:

Typical Chemistry For Boiler Steel:

%C = 0.12 – 0.21, %Mn = 0.70 – 1.45,%P = 0.025max, %S = 0.025max,%Si = 0.15 – 0.35, % Al = 0.010 - 0.025

Petro Coke and SiMn are added as per the requirement of theparticular grade.In case of grades requiring coarse grain structure killing is done with FeSi insteadIn case the heat is to be routed through Secondary refining units then Lime and Synthetic Slag are also added.In some grades such as ASTM – A537 Cl-1 FeNb is also added.In grades requiring Impact toughness at -40°C and below, Synthetic slag is added for facilitating Sulphur removal at Secondary refining units.

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4.High tensile steel: Typical Chemistry For HT Steel:

%C = 0.12 – 0.20, %Mn = 1.20 – 1.50,%P = 0.025max, %S = 0.025max,%Si = 0.15 – 0.35, %Al = 0.015 - 0.025%Nb = 0.050 – 0.070, %V = 0.040 – 0.060

• Along with Petro coke & SiMn, Micro alloys like FeNb, FeV are added during tapping.

• For HT grades different micro alloy additions are given below:• SAILMA 350/350HI

FeV – 100 to 120Kg / FeNb – 110 to 130Kg.• SAILMA 410/410HI

FeV – 130 to 150Kg / FeNb – 120 to 140Kg.• SAIL HARD

HCFeCr - 800Kg, FeV – 140Kg.• ASTM-A572 Gr 42 Ty 2/Gr 50 Ty 2

FeV – 120Kg• ASTM-A572 Gr 50 Ty 3

FeNb – 120Kg• SAIL-HITEN

FeV – 350Kg

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Grade wise Chemistry and Ferro/Micro alloy Additions at CONVERTER & SECONDARY UNITS in important Heats.

SAILMA 300/300HI

%C %Mn FeV FeNb<=12mm 0.11-0.13 1.20-1.30 80Kg Nil(In case of non availability of FeV, heats of <=12mm are not to be made)

13-20mm 0.12-0.13 1.25-1.30 Nil 70Kg

>20mm 0.13-0.15 1.30-1.40 Nil 80Kg

SAILMA 350/350HI, IS5986 Fe 510, IS 2062 E 350, DIN 17100 ST52.3BS-EN/DIN-EN 10025 S355, BS 4360 Gr 50, JIS G 3106 SM 490

%C %Mn FeV FeNb<=12mm 0.13-0.15 1.20-1.30 140Kg Nil(In case of non availability of FeV, heats of <=12mm are not to be made)

13-20mm 0.14-0.16 1.25-1.35 Nil 110Kg

>20mm 0.15-0.17 1.30-1.40 Nil 120Kg

SAILMA 410/410HI, IS 2062 E 410

%C %Mn FeV FeNb<=12mm 0.17-0.19 1.40-1.45 140Kg Nil(In case of non availability of FeV, heats of <=12mm are not to be made)

13-20mm 0.18-0.19 1.40-1.45 Nil 140Kg

>20mm 0.18-0.19 1.40-1.45 Nil 140Kg

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ASTM A 572 Gr 42 TYPE II

%C %Mn FeV FeNb<=12mm 0.12-0.14 1.20-1.30 100Kg Nil

13-20mm 0.13-0.15 1.25-1.35 100Kg Nil

>20mm 0.15-0.17 1.30-1.40 100Kg NilIMPORTANT To Be made with only FeV

ASTM A 572 Gr 50 TYPE II

%C %Mn FeV FeNb<=12mm 0.14-0.16 1.20-1.30 100Kg Nil

13-20mm 0.15-0.17 1.25-1.35 100Kg Nil

>20mm 0.15-0.17 1.30-1.40 100Kg NilIMPORTANT To Be made with only FeV

ASTM A 572 Gr 42 TYPE II T3/T4 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %V

0.10-0.12 1.30-1.35 0.025 0.015 0.20-0.30 0.010.04-0.05

(Max) (Max) (Min)IMPORTANT To Be made with only FeV

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ASTM A 572 Gr 50 TYPE II T3/T4 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %V

0.14-0.16 1.45-1.50 0.025 0.015 0.20-0.30 0.010.05-0.06

(Max) (Max) (Min)

ASTM A 572 Gr 50 TYPE III (DIRECT)

Same as SAILMA 350HI along with FeV 20-25Kg.

ASTM A 572 Gr 50 TYPE III (VAD)

%C %Mn %P %S %Si %Al %Nb %V0.14-0.16 1.45-1.50 0.025 0.025 0.20-0.30 0.015 0.04-0.05 0.02-0.03

(Max) (Max) (Min)

FeNb 100 Kg at VAD or 110 Kg at NLF-NRHFeV 30 Kg at Converter.

IS 2002 Gr II T4/T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al0.15-0.17 1.10-1.15 0.025 0.025 0.20-0.30 0.01

(Max) (Max) (Max)

Application :Intermediate andhigher temp. in welded boilers and pr. vessels

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SAILMA 300/300HI T2/T3/T4/T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Nb

0.09-0.11 1.30-1.40 0.025 0.010 0.15-0.25 0.010.02-0.03

(Max) (Max) (Min)

SAILMA 350/350HI, IS 2062 E 350, DIN 17100 ST52.3, BS-EN/DIN-EN 10025 S355 T3/T4/T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Nb

0.14-0.16 1.45-1.50 0.025 0.010 0.20-0.30 0.010.05-0.06

(Max) (Max) (Min)

Application :General structure ,buildings ,bridges, towers ,ships ,tank off shore facility,railway wagon,coaches,pr.vessels tank ,rocket launcher,oil rigs.SAILMA 410/410HI, IS 2062 E 410 T3/T4/T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Nb

0.16-0.18 1.45-1.50 0.025 0.010 0.25-0.35 0.010.055-0.06

(Max) (Max) (Min)

SAILMA 450HI, IS 2062 E 450 T2/T3/T4/T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Nb

0.16-0.18 1.45-1.50 0.025 0.010 0.30-0.35 0.010.06-0.07

(Max) (Max) (Min)

Application : For petroleum product carrying pipeline,earth moving equipment impellers,bridges towers ,off shore structure.

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SAILHARD T1/T2/T3 (VAD/LF)

%C %Mn %P %S %Si %Al %Cr %V0.23-0.14 1.45-1.55 0.025 0.025 0.25-0.35 0.010 0.40-0.45 0.05-0.06

(Max) (Max) (Min)HCFeCr 800-850 Kg and FeV 140 Kg at Converter

Application : Abrasive wear and as linear plate.

ASTM A 204 Gr A/B T3/T4 (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Mo0.17-0.19 0.85-0.90 0.025 0.025 0.15-0.25 0.01 0.45-0.50

(Max) (Max) (Min)

FeMo 1000 Kg (Approx) at Converter

Application : welded boilers and pr. Vessel.

ASTM A 537 Cl 1 T1/T2/T3/T4 (VAD/LF-RH) %C %Mn %P %S %Si %Al %Nb0.14-0.16 1.40-1.45 0.025 0.010 0.30-0.35 0.015 0.04-0.05

(Max) (Max) (Min)

FeNb 80 Kg at VAD and 100 Kg AT LF

ASTM A 588 Gr A (LF-RH)

%C %Mn %P %S %Si %Al0.16-0.18 1.20-1.25 0.025 0.020 0.40-0.50 0.01

(Max) (Max) (Min)

%Cu %Cr %Ni %V

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0.30-0.35 0.45-0.50 0.30-0.35 0.04-0.05

Cu Plates 350 Kg, HCFeCr 950 Kg, Ni 400 Kg, FeV 120 Kg at Converter

GOST 09G 2S1

%C %Mn %P %S %Si %Al0.09-0.11 1.40-1.50 0.030 0.025 0.65-0.75 0.01

(Max) (Max) (Min)

FeSi 900 Kg at Converter

GOST 09G 2S1 (VAD/LF-RH)

%C %Mn %P %S %Si %Al0.09-0.11 1.40-1.50 0.030 0.025 0.65-0.75 0.01

(Max) (Max) (Min)

FeSi 800 Kg at Converter for VAD heats and 900 Kg for LF-RH heats.

GOST 10G 2S1

%C %Mn %P %S %Si %Al0.09-0.11 1.45-1.55 0.030 0.025 0.85-1.05 0.01

(Max) (Max) (Min)

FeSi 1200 Kg at Converter

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GOST 10G 2S1 (VAD/LF-RH)

%C %Mn %P %S %Si %Al0.09-0.11 1.45-1.55 0.030 0.025 0.85-1.05 0.01

(Max) (Max) (Min)

FeSi 1200 Kg for LF-RH heats and 950 Kg for VAD heats at Converter

ASTM A 242 M TYPE – 1 (VAD/LF-RH)

%C %Mn %P %S %Si %Al0.10-0.12 0.90-0.95 0.075-0.85 0.010 0.30-0.40 0.015

(Max) (Min)

%Cu %Cr %Ni %V0.25-0.30 0.30-0.40 0.25-0.30 0.03-0.04

FeP 350 Kg, Cu Plates 350 Kg, HCFeCr 650 Kg, Ni 375 Kg, FeV 70 Kg at Converter

GOST-19282 Gr 10KHSND T4 (VAD)

%C %Mn %P %S %Si %Al0.09-0.11 0.70-0.75 0.025 0.010 0.85-0.95 0.010

(Max) (Max) (Min)

%Cu %Cr %Ni %V0.45-0.50 0.65-0.70 0.55-0.60 0.02-0.03

Additions at Converter:Petro Coke Nil LC-FeCr 1200 Kg

FeSi 1250 Kg Ni 750 KgCu (Plates) 600 Kg FeV 50 Kg

Application: Coiled plate ,wide strip used for welding and engineand for non welded structure.

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HOT SAW DISC (VAD)

%C %Mn %P %S %Si %Al %Cr %Mo %V

0.21-0.24 1.35-1.40 0.025 0.025 0.30-0.40 0.010 0.45-0.55 0.30-0.40 0.07-0.10

(Max) (Max) (Min)

HCFeCr 9000 Kg, FeMo 700 Kg, FeV 275 Kg at Converter

DMR 249 A (VAD/LF+RH)%C %Mn %P %S %Si %Al0..08-0..09 1.54-1.58 0.018 0.005 0.18-0.22 0.010

(Max) (Max) (Min)

%Nb %Ni %V 0.40-0.42 0.68-0.72 0.015-0.020

Additions at Converter for routing through VAD:

Petro Coke Nil LCFeMn 2200 Kg

Ni 830 Kg FeV 50 KgLime Full Bunker Syn. Slag 500 Kg

Additions at Converter for routing through LF-RH:

Petro Coke Nil LCFeMn 2500 Kg

Ni 930 Kg FeV 60 KgLime Full Bunker Syn. Slag 500 Kg

Additions at VAD:FeNb 85 Kg FeTi 150 Kg CaSi 75-150 Kg

Additions at LF-RH:FeNb 100 Kg FeTi 200 Kg CaSi 75-150 Kg

Application :plates for manufacture of indigenous air defence (aircraft carrier).

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SAILMA 550 HI (LF-RH)

%C %Mn %P %S %Si %Al %Nb %V0.18-0.20 1.50-1.55 0.020 0.008 0.25-0.35 0.010 0.060-0.065 0.14-0.16

(Max) (Max)

Additions at Converter:

SiMn - 3000 Kg FeV 375 Kg Lime and Syn. Slag as per Bath analysis.

Additions at LF-RH

FeNb 150 Kg at LF

Application : Penstock.

SAILMA 600 HI (VAD/LF-RH)

%C %Mn %P %S %Si %Al %Nb %V0.19-0.20 1.60-1.63 0.025 0.008 0.30-0.35 0.010 0.075-0.085 0.14-0.16

(Max) (Max)

Additions at Converter:

SiMn - 3000 Kg FeV 375 Kg for LF-RH heats Lime and Syn. Slag as per Bath analysis.

Additions at VAD/LF-RH

FeNb 140 Kg at VAD or 160 Kg at LF

Application : for missile launching pads.

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SAIL-HITEN 690 AR (VAD/LF-RH)

%C %Mn %P %S %Si %Al %V0.18-0.19 1.54-1.56 0.025 0.015 0.25-0.35 0.010 0.14-0.16

(Max) (Max)

400 Kg FeV addition at Converter

Applications: for chest of ATM safes.

WTCC – DBP T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.20-0.22 1.25-1.35 0.025 0.025 0.20-0.30 0.010

(Max) (Max)

%Cr %Mo %V 0.45-0.55 0.30-0.40 0.08-0.10

Additions at Converter:HCFeCr 900 Kg FeMo 600 Kg FeV 200 Kg

WTCC – CLP (coupling link plate through VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.15-0.17 1.30-1.40 0.030 0.025 0.40-0.50 0.010

(Max) (Max)

%Cr %Nb 0.40-0.50 0.40-0.45

Additions at Converter: HCFeCr 900 Kg

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ASTM/ASME 516 Gr 70 (VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.14-0.16 1.40-1.45 0.025 0.010 0.30-0.35 0.010

(Max) (Max)

Additions at Converter: For 8 and 10mm heats FeV - 80 Kg

BSEN – 10028 3P 275 NL-1 (VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.06-0.08 1.30-1.40 0.022 0.008 0.15-0.20 0.015

(Max) (Max)

Additions at Converter:

Petro Coke NIL LCFeMn 1300 Kg SiMn 1200 Kg

FeSi 100 Kg Syn. Slag 500 Kg Lime Full Container

ASTM/ASME 537 Cl 1 (VAD/LF-RH)

%C %Mn %P %S %Si %Al%Nb

0.14-0.16 1.40-1.45 0.025 0.010 0.30-0.35 0.010 0.04-0.045

(Max) (Max)

Additions at Converter: Syn. Slag 500 Kg Lime Full Container

Applications :Fusion welded boiler,pr. Vessel and structure.

ASTM/ASME 516 Gr 55 (VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.14-0.16 0.90-1.00 0.025 0.025 0.15-0.25 0.010

(Max) (Max)

ASTM/ASME 516 Gr 60 (VAD/LF-RH)

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%C %Mn %P %S %Si %Al 0.14-0.16 1.25-1.30 0.025 0.010 0.20-0.30 0.010

(Max) (Max)

Additions at Converter: Syn. Slag 500 Kg Lime Full Container

ASTM/ASME 516 Gr 65 DIRECT HEATS

%C %Mn %P %S %Si %Al 0.18-0.20 0.90-1.00 0.025 0.025 0.20-0.25 0.010

(Max) (Max)

Application: moderate and lower temp welded boiler and pr. vessels with improved notch toughness.

BSEN 10028 S355 NL-1 T5 (VAD/LF-RH)

%C %Mn %P %S %Si %Al NiNb

0.06-0.08 1.55-1.60 0.020 0.010 0.20-0.30 0.010 0.45-0.50 0.045-0.050 (Max) (Max)

Additions at Converter:

Petro Coke NIL LCFeMn 2500 Kg SiMn 500 Kg

FeSi 150 Kg Syn. Slag 500 Kg Lime Full Container

Application: Dishing plates and steam.

IRS M41 (VAD/LF-RH)

%C %Mn %P %S %Si %Al 0.08-0.10 0.40-0.45 0.09-0.10 0.010 0.40-0.50 0.010

(Max)

%Cr %Ni %Cu %V 0.40-0.45 0.25-0.30 0.35-0.40 0.035-0.040

Additions at Converter:

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Petro Coke NIL LC FeMn 800 Kg FeP 450 Kg

FeSi 800 Kg HCFeCr 900 Kg Ni 400 Kg

Cu (Plates) 450 Kg FeV 120 Kg

Syn. Slag 500 Kg Lime Full Container

Steel Quality Steel Grades

Covered

Application

High TensileMicro-alloyed(Ultra HighStrength)

SAILMA-600HI

SAIL-HITEN

SAILMA-550HI

For Missile Launching

Pads

For Chest of ATM

Safes

For Penstock

Line pipe API-5L-GR-A,GR-B,X42 P ipe line structural

StandardStructuralGeneral Grades

JIS-G-3101-SS-400 General structure,

Bridges , ships

Rail Steel IRS-T12-GRADE-880-1996(UTS-90,R-52,R-60

Flat bottom

symmetrical rails.( &

Blooms )

Boiler QualityHigh TensileMicro-alloyedControl Rolling

A-588M Welded bridges &

buildings where

saving in weight or for

corrosion resistance.

Ship BuildingGeneral

NES-791-P-1 Weld able steel for

general structural &

Engg. purpose

Strip & Sheet General Grades

I S-513-O-BSL Sheets & strips for bending & drawing

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CONTINUOUS CASTING

Continuous casting technique accounts for more than 60% of total liquid steel in the world. The main advantages of steel processing through CC route are higher yield, lower energy consumption, elimination of primary mills.

THE PRODUCTION STAGES:During continuous casting, the liquid steel passes from the pouring ladle, with the exclusion of air, via a tundish with an adjustable discharge device into the short, water-cooled copper mould. The shape of the mould defines the shape of the steel. Before casting, the bottom of the mould is sealed with a so-called dummy bar. As soon as the bath reaches its intended steel level, the mould starts to oscillate vertical lyin order to prevent the strand adhering to its walls. The red-hot strand, solidified at the surface zones, is drawn from the mould, first with the aid of a dummy bar, and later by driving rolls. Because of its liquid core, the strand must be carefully sprayed and cooled down with water. Rolls on all sides must also support it until it has completely solidified. This prevents the still thin rim zone from disintegrating.Once it has completely solidified, the strand can be divided by mobile cutting torches or shears.Intensive cooling leads to a homogeneous solidification microstructure with favourable technological properties. High casting speeds are achievable nowadays; depending on dimensions and the number of strands that are simultaneously cast, speeds of about 0.6 to 3.5 m/min are possible for slabs. Primary features of continuous casting: •Sequence casting and composite casting with the aid of turrets, which take up two ladles, and swivelling devices for the wear-exposed tundishes. This allows dissimilar grades of steel to becast directly after each other.•Some kind of protection for the pouring stream between the ladle and tundish as well as between the tundish and the mould, with the aid of inert gases for improving the cleanness(preventing reoxidation).•Precise strand guidance and consistent strand cross-section by means of matching roll design of high precision and/or split rolls.

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•Intensive secondary cooling of the strand with the aid of uniform and metered spraying.•Electromagnetic stirring in the mould to improve surface quality (no surface shrinkage cavities or inclusions close to the surface).Electromagnetic stirring of the partly solidified strand to obtain a globular - non-directional -solidification microstructure with no segregation zones in the centre of the strand.

CONCLUSION

Bhilai Steel Plant is a public sector organization which comes under the supervision of STEEL AUTHORITY OF INDIA LTD. It was really a good experience in my life time, where I learnt many things during 6 WEEKS in-plant training at BSP. Bhilai Steel Plant gave me an opportunity to know about the industrial world. In the company I learned about how the management theories and concept are applied in an organization. I saw how the managers managed a large number of employees and machines to run the company with a profit. More over the in plant training was a good exposure for me to the working conditions of the organization. Another important aspect which I noticed in the company was regarding the discipline followed in the office. I came to know practically how an organization works. And I learnt how various products are produced like Blooms, Billets, Slabs, Beams, Channels, Angles, Plates and Rail Tracks and saw the various methods applied for producing these. The project contains the study of DESULPHURISATION PRACTICES AND SPECIAL STEELMAKING. We learnt refinement of hot metal which is produced by blast furnace into steel .With the help of various treatments done in DSU,BOF,LF,VAD,RH we manage to obtain steel with least amount of impurities(S, C, Si, P, Mn) and high quality .Moreover, it gives a profitable and economical approach to steel making. Various grades of steel (above mentioned) are produced according to the demand of the customer. Near about 5001 grades of steel are till date produced by BSP.

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LIMITATIONS

LIMITATION OF THE STUDY :

Some data were confidential therefore were not available for analysis.

TIME FACTOR:- Time factor was the chief limitation of study. Limited

time was allotted for the study.

INFORMATION FROM RESPONDENTS :

Some biased response came from respondent and Finding stated in

the report was based on the answers from the questionnaire. So the effect of

misinterpretation and wrong answers may affect the outcome of the project.

The research has focused his attention mainly in and around Bhilai.

As the major customer of BSP products are not individual persons. It was

very difficult to formal feedback from them.

4. Many a times BSP is not in a position to supply the full quantity of material for

which the payment has been received. In such cases, the refund of the excess

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amount should be thought a stream lined process so that it does not tack long

time.

5. Prices list made available to the various re-rollers every month by BSP.

6. The material being sold by marketing department should accompany test

certificate mentioning only the range of carbon content in it for which the

customers are ready to pay reasonably higher prices.

7. Generation of secondary products must be tried to minimize which will help the

BSP in optimum use of raw materials.

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CHAPTER - 11

BIBLIOGRAPHYBIBLIOGRAPHY

WORKING NOTES SMS-2 DEPARTMENT

WEB SITE OF SAIL www.sail.co.in

WEB SITE OF BSP www.bsp.com

OTHER SITES: - www.google.com

www.wikipedia.com

REFERENCES BOOKS BY Ahindra Ghosh and chatterjee & R.K Tupkary

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