FR(R=0) 3379 for HSM RSP

ROURKELA STEEL PLANT

INSTALLATION OF HOT STRIP MILL

FEASIBILITY REPORT

STEEL AUTHORITY OF INDIA LIMITED

CENTRE FOR ENGINEERING &TECHNOLOGY RANCHI - 834 002

MARCH 2012 CET/05/RN/3379/FR/RF/01/R-0

RSP CONTENTS CET/05/RN/3379/FR/RF/01/R-0NEW HOT STRIP MILL Page 1 of 3

CONTENTS - CHAPTERS

Chapter no.

Description

Page no.

1. Summary 1.1-1.3

2. Background 2.1-2.11

3. Selection of Alternatives 3.1-3.3

4. Project Description 4.1-4. 74

5. Project Implementation 5.1-5.1

6. Financial Analysis 6.1-6.5

7. Recommendation 7.1-7.1

Annexures

Drawings

RSP CONTENTS CET/05/RN/3379/FR/RF/01/R-0NEW HOT STRIP MILL Page 2 OF 3

CONTENTS - ANNEXURES

ANNEXURE NO.

DESCRIPTION NO. OF PAGES

2.6.2-1 Copy of Letter for Assignment From RSP 1

4.2-1 Tentative Product Mix

5.1-1 Implementation Schedule (Pre- Ordering Activities) 1

5.1-2 Implementation Schedule (After Stage-II Approval) 1

6.1.1-1 Capital Cost Estimate Summary 1

6.1.1-2 Detailed Capital Cost Estimate 3

6.1.1-3 Basis Of Capital Cost Estimate 4

6.1.1-4 Volume Of Work for Capital Cost Estimate 1

6.5.1.6-1 Works Cost Of Production 1

6.5.2.2-1 Gross Margin Calculation 1

6.6.1-1 Cash Flow Statement 6

6.6.2-1 Financial Analysis 1

RSP CONTENTS CET/05/RN/3379/FR/RF/01/R-0NEW HOT STRIP MILL Page 3 of 3

CONTENTS - DRAWINGS

Sl. no. Drawing no. Description 1 CET RN 3379 CEO 00 001 R=0 General Layout of HSM Location

2 CET RN 3379 RF1 00 003 R=0 Layout of Proposed Hot Strip mill

3 CET RN 3379 RF1 00 004 R=0 Layout of sheet shearing Line

4 CET RN 3379 EE1 00 001 R=0 Single Line diagram of Power distribution Scheme

RSP CET/05/RN/3379/FR/RF/01/R-0NEW HOT STRIP MILL Page 1.1

1 SUMMARY

1.1 Rourkela Steel Plant (RSP) produces a large variety of steel products which include Hot Rolled Coils/Sheets, Heavy Plates, Cold Rolled Products, Pipes and Cold Rolled Non-Oriented Products. RSP is currently modernizing/expanding their facilities. After completion of the ongoing modernization, the crude steel production of RSP is envisaged to be 4.2 Mtpa. The saleable products after completion of the modernization is envisaged to be 3.99 Mtpa which includes 0.82 Mtpa of slabs.

1.2 The distribution of slabs after the ongoing expansion has been considered as follows :

Hot Strip Mill : 1.85 Mtpa

Existing Plate Mill : 0.53 Mtpa

New Plate Mill : 1.00 Mtpa

Sales/IPT : 0.82 Mtpa

Total slabs : 4.20 Mtpa

1.3 Hot Strip Mill is the major consuming unit of slabs at RSP which produces HR coils for sale and also for feed material to downstream production units of RSP like Pipe Plants, Cold Rolling Mills and Silicon Steel Mill. The existing Hot Strip Mill of RSP is an old mill commissioned in mid 1960s. This mill has been modernized three times in last two and half decades. The rated capacity after the last modernisation was 1.65 Mtpa. The mill is designed for producing hot rolled coils with strip thickness range of 1.6-18 mm, strip width of 700-1550 mm and maximum coil weight of 17 t. The average production for last five years through this mill is around 1.55 Mtpa (input slabs 1.593 Mtpa) with the best production of 1.61 Mtpa (input slab 1.648 Mtpa) in the year 2007-08.

1.4 As per the ongoing expansion of RSP, the existing Hot Strip Mill will have to process 1.85 mt of slabs per year. With ageing of the equipment that were not modernized earlier and in view of obsolescence of such equipment, the productivity of Hot strip mill is low. No modernisation of the existing Hot Strip Mill has been envisaged in the ongoing modernisation. Hence, with the present status, the Hot Strip Mill will have difficulty in processing 1.85 Mtpa of slabs without substantial investment. Even after processing 1.85 Mtpa form the existing Hot Strip Mill, 0.82 Mtpa of slabs remains which will have to be sold as semis. The quality of the products, viz., the thickness tolerance, width tolerance, profile & shape and metallurgical properties are inferior to those produced from modern


mills. The mill has been designed for lower strip width (upto 1550 mm) and lower coil weight (upto 17 t). Higher strength of HR coils cannot be produced through this mill due to limitations in the mill. The mill will also require regular investment as some sustenance schemes.

1.5 The quality of products from the existing Hot Strip Mill can be improved to some extent by extensive modernisation of the mill. The capacity can also be raised marginally through the modernisation. This will require investment of around Rs 1200 to 1500 Crore and a shut down of around 60 days.

1.6 Even after such investment, many of the limitations of the existing Hot Strip Mill will remain. Around 0.67 Mtpa of slabs from RSP will remain as semis. Maximum strip width will be upto 1550 mm and maximum coil weight will be 17 t only. Higher grades like API X-80 cannot be rolled through this mill. The equipment, which will be retained, will be older and may prove as weaker areas.

1.7 In view of processing the required tonnage of slabs which will be available after the ongoing modernisation of RSP and to enrich the product range with wider strip, higher coil weight & excellent product quality, it is envisaged to install a new Hot Strip Mill 3.0 Mtpa capacity with state of the art facilities. The existing Hot Strip Mill will be phased out after stabilisation of the new Hot Strip Mill.

1.8 The envisaged Hot Strip mill will be located near the slag granulation plant after necessary site development. The Hot Strip Mill will have following broad parameters :

Strip thickness : 1.2 - 25.4 mm

Strip width : 725 - 2100 mm

Max. Coil weight : 35 t

Specific Coil weight : 20 t/mm (max)

1.9 Major facilities in the Hot Strip Mill will include, two nos. of Walking Beam type Reheating Furnaces, High pressure desclaing, a 4-high Reversing Roughing Stand with Edger, Passive covers, Crop Shear, six nos. of 4-high finishing stands, Laminar cooling system, two nos. of down coilers, coil conveying system, etc. The mill will have modern control system including automatic strip width control, thickness control, profile & shape control, metallurgical properties, etc. to produce hot rolled coils of excellent quality. A Roll shop will be provided adjacent to the Mill to cater to the requirements of the new mill. A Sheet shearing Line of 400,000 tpa capacity will also be installed for making sheets/plates from the HR coils produced


through the new mill. The existing Dividing Line will also be utilised for producing hot rolled sheets. Supporting facilities and infrastructures including power supply, Water & utilities, road & rail network will also be provided at the proposed Hot Strip Mill area.

1.10 It is estimated that the project will be completed in 42 months from the date of sanction and 36 months from the date of stage-II approval. The project will be implemented under four packages, viz. soil Investigation & survey package, Site development package, Rail Network package and the Mill package.

1.11 The capital cost estimate for the New Hot Strip Mill, RSP has been estimated to be Rs. 3879.42 Crore, net of cenvat credit of Rs. 356.03 Crore and inclusive of IDC component of Rs 192.06 crore.

1.12 Techoeconomic parameters of the project areindicated below :

Gross Margin : Rs 931.18 Crore

IRR (Pre tax) : 21.36%

IRR (Post tax) : 18.08%

NPV at 10% discount (pre tax) : Rs 2875.83 Crore

NPV at 10% discount (post tax) : Rs 1782.92 Crore

If only inhouse slabs (2.67 Mtpa) are considered, the IRR (post tax) works out to be 16.41%.

1.13 A new Hot Strip Mill with modern features is required to roll the required volume of slabs available after the ongoing modernisation of RSP and to avoid sales of semis as slabs. Market requirements of higher coil weight, wider strip, higher strength grades, excellent product qualities, etc. will be met through the new Hot Strip Mill.

The project is technically feasible and technoeconomically viable and hence recommended for implementation.

RSP CET/05/RN/3379/FR/RF/01/R-0 NEW HOT STRIP MILL Page 2.1

2 BACKGROUND

2.1 Rourkela Steel Plant (RSP) produces variety of saleable products which include hot rolled coils & sheets, heavy plates, pipes, cold rolled coated & uncoated coils/sheets and electrical steel (cold rolled non oriented steel). Rolling & processing facilities at RSP to produce these products consist of the following complexes :

Hot Strip Mill Plate Mill ERW Pipe Plant SW Pipe Plant Cold Rolling Mills Silicon Steel Mill A new Plate Mill of 1.0 Mtpa capacity is also under installation.

The feed material to the Hot Strip Mill and the Plate Mill are cast slabs whereas the feed materials to the other mills are hot rolled coils produced from the Hot Strip Mill.

2.2 Existing Hot Strip Mill

2.2.1 The 1700 mm Hot Strip Mill (HSM) of Rourkela Steel Plant was installed in mid 1960s for producing 1.15 Mtpa of Hot rolled (HR) coils mostly of normal carbon steels. This mill has been modernized three (3) times in last two and half decades. The modernization activities were carried out with different objectives related to improvements in productivity and product quality. In the last modernization, carried out in early 1990s, the production capacity was enhanced to 1.65 Mtpa.

2.2.2 The existing 1700 mm Semi-Continuous Hot Strip Mill broadly comprises of the following facilities :

- 225 t/h walking beam type reheating furnaces 2 nos.

- Primary descaler

- 2-Hi reversing rougher (R0) with vertical edger (V0)

- 4-Hi reversing rougher (R1) with attached edger (E1)


- 4-Hi single pass rougher (R2) with attached edger (E2)

- Coil box

- Rotary crop shear

- Pinch roll scale breaker

- Finishing train comprising of six 4-Hi stands (F1 F6) with hydraulic AGC in stands F3 F6

- Run-out table with laminar strip cooling system

.- Two downcoilers (C4 & C5)

- Coil conveying system with coil weighing, banding and marking facilities

- Hot rolled strip shearing line

2.2.3 Main Parameters

The existing Hot strip mill is presently rolling Low carbon steels, CRNO steels, API grade steels up to X-65. The input slab sizes and rolled coil parameters, as designed, are as follows:

Slab Dimensions :

Parameters Designed Actual

Thickness : 180 210 mm 180 220 mm

Width : 700 1550 mm 740 1450 mm

Length : 3500 8600 mm 6000 8900 mm

Weight : 17 t max 17 t max

Transfer bar Dimensions :

Thickness : 20 32 mm 20 32 mm

Coils/Strip Dimensions :

Thickness : 1.6 18 mm 1.9 12 mm

Width : 700 1550 mm 740 1450 mm

Inner diameter : 760 mm 760 mm


Outer diameter : 1700 mm max. 1700 mm

Weight : 17 t max. 17 t max

Specific Weight : 13 kg/mm max.

Designed mill capacity : 1,650,000 tpa

Best achieved production in the mill was 1.61 MT in the year 2007-08. Average of last 5 years production is 1.555 Mtpa of HR coils.

2.2.4 A part of the HR products of the existing HSM is used as input material in the down stream units, viz, Cold Rolling Mill, Silicon Steel Mill, Spiral welded pipe plant and ERW pipe plant. Balance is sold as HR coils or HR sheets.

2.3 Ongoing Expansion/Modernisation of RSP

2.3.1 Rourkela Steel Plant is already under expansion & modernization. Following facilities are being added/expanded during the ongoing modernization :

A 67.7 m new Coke Oven battery A 4060 m3 new Blast Furnace A new 150 t BOF at SMS-II Secondary Refining units (1 Ladle Furnace and 1 RH-OB) at

SMS-II

A single strand Slab Caster at SMS-II A new Plate mill of 1 Mtpa capacity (expandable upto 1.8

Mtpa in future)

After completion of the ongoing expansion/modernization, the production level at various processing steps of RSP will be as follows :

Hot Metal : 4.5 Mtpa

Crude Steel : 4.2 Mtpa

Saleable:

Plates from Existing Plate Mill : 0.4890 Mtpa

Plates from new Plate Mill : 0.9295 Mtpa


Hot Rolled Coils/Sheets : 1.2454 Mtpa

Cold rolled products : 0.3017 Mtpa

Pipes : 0.1300 Mtpa

CRNO coils/sheets : 0.075 Mtpa

Total finished products : 3.1706 Mtpa

Semis (Slabs) : 0.8200 Mtpa

Total saleables (including semis) : 3.9906 Mtpa

2.3.2 Distribution of Slabs

The distribution of slabs after the ongoing expansion has been considered as follows :

Hot Strip Mill : 1.8500 Mtpa

Existing Plate Mill : 0.5300 Mtpa

New Plate Mill : 1.0000 Mtpa

Sales/IPT : 0.8200 Mtpa

2.4 Limitations of Existing Hot Strip Mill

2.4.1 As per the ongoing expansion of RSP, the existing Hot Strip Mill will have to process 1.85 Mt of slabs per year. With ageing of the equipment that were not modernized earlier and in view of obsolescence of such equipment, the productivity of Hot strip mill is low. It was envisaged to process 1.65 Mtpa of slabs through this mill during the last modernization in 1992. The best throughput in this mill was 1.648 MT in the financial year 2007-08. Average throughput for last five years is 1.593 Mtpa. Hence, with the present status, the Hot Strip Mill will have difficulty in processing 1.85 Mtpa of slabs without substantial investment. The quality of the products from this mill is inferior to those produced from modern mills.

2.4.2 Limitations of the existing Hot Strip Mill of RSP can be summarized as follows :

Production capability The capacity of the mill, after last modernization, was rated as 1.65 Mtpa. The cycle time in roughing mill area is high due to the present layout and limitations in existing roughing mill. The


old roughing stands R1 and R2 have become weaker with time, resulting in low drafting and speed capabilities. Also, the drafting and speed capabilities of R1 and R2 are much lower as compared to present day roughing stands limiting the possibilities of higher production.

The cycle time of finishing stands is also high because of drive power limitations. Further, the load on finishing mill is higher due to less drafting from the roughing mill. Work roll changing time in this mill is more than 30 minutes whereas modern mill has work roll change time of around 5 to 7 minutes only. The combination of these factors restricts higher production from the existing Hot Strip Mill.

Product sizes The mill is designed to produce HR coils with maximum width of 1550 mm. Demand for higher width HR coils is increasing especially for API grades. New mills are coming which can produce strip upto 2100 mm width and hence will have advantage on account of this. The Mill is designed to roll strip with thickness range of 1.6 mm 18 mm. However, a strip thickness range of 1.9 mm to 12.5 mm is being rolled from this mill due to constraints in roughing and finishing mills. Modern Hot Strip Mills can produce HR coils with minimum strip thickness upto 0.8-1.2 mm which find applications as a substitute of CR coils at various applications. Also, HR coils of higher thickness are in demand.

Grades of HR coils The old roughing stands R1 and R2 have become weaker with time, resulting in low drafting and speed capabilities. Also, the drafting and speed capabilities of R1 and R2 are much lower as compared to present day roughing stands limiting the possibilities of higher production and rolling of stronger Higher strength HR coils cannot be produced through existing mill due to limitations in drive power, poor health of equipment and other factors. Demand of stronger material upto API X-80 is rising.

Lower Coil weight The existing Hot Strip Mill is designed for maximum 17 t coil weight (Specific Coil Weight 13 kg/mm). Higher coil wt. (upto 30-35 t) is preferred and is available from other mills.

Product Quality


The basic parameters that determine the quality of HR coils are

- Width tolerance : The mill lacks Automatic Width Control (AWC) system and there are variations in width of the rolled strip. Width variations of the strip are of the order of +20 to 30 mm, whereas products form competitors are having width tolerance within 0, +5 mm. Head end fishtails are also observed in coils produced through the existing mill.

- Thickness tolerance : Thickness tolerance achieved in the products from this mill is more than 100 m where as a thickness tolerance of 25 50 microns are achieved at other modern mill. HAGC was provided in finishing stands from F3 to F6 only. The existing HAGC is of older design, has poor resolution and repeatability. The controls & automation level are outdated. Hence the thickness tolerance achieved through this mill is quite wide.

- Strip Profile: No provision for strip profile control has been provided with the mill. Strip Profile of all the strip cannot be measured as there is no profile measuring gauge installed at the mill. In general, the profile achieved from this mill is of the level of 100 micron whereas modern mill achieve a level of Profile 40 60 micron.

- Strip Shape & flatness: No provision has been provided for measurement and shape control and the shape of the strip achieved through this mill is poor.

- Strip surface quality: Surface quality of the rolled strip is also not up the mark as no provision for anti-peeling /oxide suppression has been provided.

- Metallurgical properties of finished strip: The existing laminar cooling system is of older open-loop design. The settings are based on operator experience only and has a poor repeatability. Hence the required metallurgical properties are not achieved. Further, for better metallurgical properties, the finishing mill needs a good temperature regime that can be achieved with higher transfer bar thickness. With limitations of drive powers in the finishing stands, the possibilities are limited.

It can be inferred from the above that the present quality of HR coils from RSP Hot strip mill falls far below the present market demand and the HR coils available from competitors.


Health of equipment Health of various equipment which has not been modernized during last modernization, is poor and unpredictable breakdown occurs. These equipment need to be revamped/replaced for long time sustenance.

2.5 Necessary Modernisation required in Existing Mill

2.5.1 A part of the mentioned limitations can be overcome by modernizing the existing Hot Strip Mill. Major areas required of modernization/revamping will include the following.

Roughing Mill Area No modernization has been carried out in the existing roughing stands R1 and R2 and the stand equipment has inability to roll at designed speeds and drafting capability is low. The existing roughing stands R1 and R2 need to be replaced with a new heavy roughing stand alongwith edgers with higher drafting and speed capabilities and automatic width control.

The roller tables are inadequately powered w.r.t. the increased slab weight. The roller tables are prone to frequent breakdowns. Most of the roller tables, which are old and have not been modernized earlier, will have to be replaced with new roller table assemblies along with new individual AC drives.

The existing crop shear will have be modified to facilitate quick shear blade change and to have provisions for optimization of crop ends.

Finishing Mill Area The finishing mill stands are operated at lower speed of rolling than designed due to its limitations in drive system. There is no provision for hydraulic AGC in F1 & F2. There is no provision of profile & flatness control facility. Roll changing time is high. Load cells have erroneous performance. Thyristor control systems of existing DC motors are old and have poor controllability. Existing DC drives of Finishing stands are not sufficient for higher productivity. Also existing drive motors are prone to break down and availability of spares is becoming difficult. Inter-stand loopers have high inertia, low response and not able to generate tension for higher thickness strips. Existing inter-stand guides & strippers


are prone to frequent break downs. Absence of inter-stand strip cooling, oxide suppression affect strip quality

The finishing mill area need to be up-graded thoroughly for higher power and modern quality control features so as to achieve high productivity and better product quality.

Drive system of finishing stands need to be replaced with higher power AC drives. Existing screw-down system and hydraulic cylinders need to be replaced with long stroke cylinders for achieving better thickness tolerance and reduction in in work roll change time. Replacement of old load cells with new load cells for better and more accurate roll force measurement and for facilitating better AGC operations is required. Roll bending and shifting system alongwith housing blocks need to be provided at all stands for achieving better profile and shape of the rolled product. Existing mechanical mill entry guides have to be replaced with new hydraulic entry guides and strippers having better operation and easier maintainability. Replacement of existing roll cooling system with new roll cooling system is required alongwith inter-stand strip cooling system and anti-peeling system for better strip quality and higher roll life. Existing low response electro-mechanical loppers with high response hydraulic loopers and tensiometer is required for better control of inter-stand strip tension and to eliminate width variation (Necking) in the finishing stands. New state of the art automation system with mathematical models will have to be implemented for better quality of the products.

Laminar cooling Existing laminar cooling system is open-loop and is of older design with no edge masking. The existing laminar cooling system will have to be replaced by a new laminar cooling system of latest design with edge masking facilities to achieve uniform and better metallurgical properties of strip and to achieve better coiling temperature control. ROT Roll cooling facilities will also have be provided. The new laminar cooling system will be linked with the microstructure control models.

Strip Measuring gauges A new gauge house will have to be provided at the exit of the finishing mill train with strip thickness, width, profile and flatness instrumentation for measurement and control of strip quality.


Down coilers Existing entry guides will have to be replaced with new hydraulic entry guides for better guiding of strip and better coiling in the down coiler. Replacement of existing down coiler pinch rolls with new wear resistant pinch rolls is also required to reduce down time for replacement of pinch rolls and enabling coiling of higher strength strip. Existing down coiler wrapper rolls need to be replaced with new wear resistant wrapper rolls to reduce down time for replacement of wrapper rolls. Modification of existing automatic jump control system of wrapper rolls is also needed.

Coil conveying Augmentation of existing coil conveyors is required for handling higher production rate and to restore health.

Roll shop Augmentation of roll shop is required for handling new work rolls and to match higher production requirements

Electrics Latest state of art electrical equipment, drives and controls for all the facilities to match with the technological requirement of modernization scheme will be required. They broadly include new AC drive system for the new roughing stand & edger, finishing stands, roller tables, replacement of existing drive regulation system with digital drive regulation system.

Automation System State of Art level II automation and computer facilities alongwith required instruments & actuators are required in the Hot Strip Mill for optimizing and controlling the various parameters for better quality of the products. Modules required in the mill includes, Mill Tracking, Mill racing, Rougher & Finishing mill setup, temperature set up model, laminar cooling model, Microstructure model, Profile & Flatness control, Slab & coil yard mapping, etc.

Sustenance schemes under AMR Besides the modernization of the above mentioned areas, other AMR schemes are also required to restore the overall


health of the equipment and debottlenecking which are under process by RSP.

If the above mentioned schemes are implemented, following benefits are expected :

The product qualities, viz thickness tolerance, profile & shape, width tolerance and metallurgical properties will improve.

Capacity of the mill will increase marginally. 2.5.2 Limitations to be remained after modernisation

Implementation of the schemes indicated in the preceding paragraphs will require a capital cost of around 1200 to 1500 crore. Even after the modernization, following limitations will remain with the existing Hot Strip Mill.

The mill cannot accommodate the required tonnage of slabs which will be produced at RSP after the ongoing modernization. Approximately 0.70 Mtpa of slabs will remain as semis even after complete modernization of the existing Hot Strip Mill.

Maximum strip width will remain to be lower (upto 1550 mm) Coil weight will remain to be lower (17 t max). Higher grades like API X-80 cannot be rolled in this mill. The equipment, which will be retained, will be older and may

prove as weaker areas in getting full benefits of the modernization.

2.6 Plan for New Hot Strip Mill

2.6.1 The existing Hot Strip Mill has limitations in accommodating the required quantity of slabs which will be available after the ongoing modernization of RSP. The mill is designed for lower width and lower coil weight. Higher strength HR coils cannot be produced through this mill due to limitations in Roughing & Finishing mill. The equipment condition is not up to the mark due to its age. Many of the equipment is becoming obsolete and spares availability is getting difficult. Electrics, control and automation system is outdated. Products quality w.r.t. dimensional tolerances and metallurgical properties are inferior to those available from competitors.


A thorough modernisation of the existing Hot Strip Mill will be required to improve the quality, specially the dimensional tolerances, of the rolled products and to restore the health of the equipment for long term sustenance. Productivity of the mill can also be raised marginally with the modernisation and the mill. The investment required for this modernisation will be around Rs 1200 to 1500 crore However, around 0.70 Mtpa of slabs of RSP will remain as semis even after the massive modernisation. Other basic limitations of the mill like lower width, thickness limitations, coil weight, limitation of producing higher strength coils, etc. will remain.

In view of the above, RSP plans to install a new Hot Strip Mill with wider product range (strip width upto 2100 mm and strip thickness from 1.2 mm to 25.4 mm) with state of the art facilities. The mill will have the capacity of 3.0 Mtpa of slabs rolling Out of the total 3.0 Mtpa, 2.67 Mtpa will be inhouse slabs and balance 0.33 Mtpa of slabs will be purchased/IPT.

The existing Hot Strip Mill will be closed after commissioning and stabilization of the new Hot Strip Mill. However, the existing Sheet Shearing Line (Dividing Line) will be retained for producing the sheets/plates from the HR coils produced through the proposed Hot Strip Mill.

2.6.2 CET has been assigned vide RSP letter no. AMR-M&SC/Consulatancy/15/433-37 dated 17.03.2011 (copy enclosed Annexure 2.6.2-1) for feasibility study of the proposed Hot strip Mill. Accordingly, draft feasibility report was submitted by CET in August 2011. Subsequently, discussions with RSP on the draft FR was held in February 2012 and the FR has been finalised accordingly.

2.6.3 The co-operation provided by RSP and other agencies in preparation of this report is gratefully acknowledged.


3 SELECTION OF ALTERNATIVE

3.1 Approximately 1200 m x 600 m area will be required for installation of the Hot Strip Mill. Following two alternatives were considered for location of the proposed facilities :

Alternative-I :Near Hanuman Vati

Under this alternative, the proposed Hot Strip Mill will be located outside the existing plant boundary near Hanuman Vati.

This site is farther from the existing RSP boundary. All the infrastructures will have to be created at this site. Longer network of railways tracks, longer gas and water pipelines, etc. will be required at this site. There is a water lagoon between the existing boundary of RSP and this site which has to be taken care for making the infrastructure. Power corridor is also passing through this site.

Alternative-II: Near Slag Granulation Plant

Under this alternative, the proposed Hot Strip Mill will be installed near the slag granulation plant. This site was earlier used for dumping Blast Furnace slag which is not in use at present. This site is adjacent to the existing plant boundary. The facilities for the proposed mill will be partly inside and partly outside the existing plant boundary (major area will be outside the existing plant boundary). The location is indicated in Drawing no. CET RN 3379 CE0 00 001 R=0.

A road is passing between RSPs existing boundary and this site which will have to be diverted. Rail network is already existing near this site which will have to be further extended/strengthened. Creating infrastructures will be easier at this location.

Selection of alternative

Site under alternative-II is adjacent to the existing plant boundary and it will be easier to create required infrastructures for the proposed Hot Strip Mill. Hence, this site is more suitable and is selected. for the proposed Hot Strip Mill.


4. PROJECT DESCRIPTION

4.1 It is envisaged to install a Hot Strip Mill alongwith a Sheet Shearing Line at Rourkela Steel Plant. The Hot Strip Mill will be designed for rolling 3.0 Mtpa of slabs. A new sheet shearing line of 0.40 Mtpa capacity will also be installed within the proposed Hot Strip Mill Complex. The existing Sheet Shearing Line (Dividing Line) will also be retained and will be utilized for production of sheets from the HR coils produced through he proposed Hot Strip Mill.

The proposed Hot Strip Mill will be located near the Slag Granulation Plant. Location of the proposed mill is indicated in Drawing no. CET RN 3379 CE0 00 001 R=0.

4.2 Main Parameters

Broad Parameters of the proposed Hot Strip mill will be as follows:

Slab dimensions Slab thickness : 200 300 mm carbon steel Slab width : 725 2100 mm Slab length : 5000 11000 mm Slab weight, max : 35 t

Strip dimensions Strip thickness : 1.2 25.4 mm Strip width : 725 2 100 mm Coil weight, max : 35 t Spec. coil weight : max. 20 kg/mm

Rated Production Capacity : 3.00 Mtpa (Input slabs) 2.94 Mtpa (HR coils)

Main Steel grades Carbon structural steels HSLA Low carbon steels High strength steels LPG cylinder steel Line pipe steels up to API 5L X80 Steels for Automotive applications Boiler and pressure vessel quality


DDQ and EDDQ - steels CQ steels CRNO

A tentative size wise product mix is indicated at Annexure-4.2-1.

The new Hot Strip Mill will be equipped with advanced control systems in roughing and finishing mill for rolling of strips with best tolerances for strip thickness, strip profile, strip flatness, strip width, final rolling and coiling temperature.

Layout of the Hot Strip Mill is indicated in Drawing no. CET RN 3379 RF1 00 003 R=1.

4.3 TECHNOLOGICAL FACILITIES

4.3.1 SLAB YARD

Slabs coming from the Steel Melting Shops will transported by railway wagons.to the Hot Strip Mill and will be stored in the slab storage yards. The slab yards will have storage capacity for approximately five days. The slabs stacked in the slab yard will be picked up by overhead crane and placed onto the slab yard roller table. Slabs will be weighed and measured before transported further on to the charging roller table in front of the furnaces.

4.3.2 REHEATING FURNACES

Two nos. of reheating furnaces will be provided to heat & soak the input slabs to the required rolling temperature. The reheat furnaces will be of walking beam type.

4.3.2.1 Charging & Discharging Equipment

Slabs as received will be perfectly aligned automatically and positioned in front of furnace and then pushed into the furnace with the help of pusher. The pushed slab will be carried to discharge side with the help of walking beam mechanism. From discharge position the extractor will lift the slab and put down the same on discharge roll table

4.3.2.2 Reheating Furnace

The envisaged major technological parameters are as mentioned below :

Type Walking Beam Furnace with two row charging

Capacity 300 tph based on cold slabs (for reference


size) Quantity(No. of Furnaces) 2 nos. Reference slab size Length : 6-10m

Width: 1500 mm Thickness : 250 mm

Fuel gas Duel Fired Furnace with provision of firing with Furnace Oil (LCV -9500 kcal/kg) & Mixed Gas (LCV -3600 kcal/Nm3)

Input material Charging temperature 20 o C (cold) Discharge temperature 1280o C max. Temperature difference (surface and core)

25 0C max.

Specific fuel consumption 0.3 Gcal/t (on yearly average basis) at furnace discharge

Skid cooling Water Charging by pusher Discharging by extractor

Walking beam furnace skids will of high temperature and wear resistant steel with high rigidity. The furnace will be packed from inside with refractory and insulation material to limit the furnace skin temperature to about 500 C above ambient temperature. The movement of the walking beams will be hydraulic. A pair of movable skids walking beam will have central driving mechanism. One cycle of operation consists of lifting, forward movement, lowering and reverse movements of walking beams during which slabs will be advanced by predetermined distances. Hydraulic power pack will be provided for the movement of the walking beams. Centralised grease lubrication system will also be provided for the furnaces

Combustion System

The combustion system will include the following:

1) Burners

2) Combustion air piping

3) Mixed Gas & Furnace Oil Piping

4) Combustion air blower

5) Metallic recuperator for air preheating

Three nos. of Combustion Air Blowers (2W+1S) with VVVF drive have been envisaged for furnace.


Air Recuperator

A metallic recuperator will be installed in the flue channel to preheat the combustion air to about 650 oC. The recuperator will be cross-counter flow type. Dilution air fan & Hot Air Bleed will be provided for protection of recuperator

Waste Gas Flue Exhaust System

Waste gases from furnace will be taken out through the opening provided on the charging end, and will be exhausted to atmosphere through underground tunnel with forced draft fan & chimney of adequate height. The system will be so designed that waste gas temperature at the base of the chimney will be kept around 250 deg C.

Combustion System

The combustion system will include the following: 1) Burners 2) Combustion air piping 3) Synthetic Gas Piping 4) Combustion air blower 5) Metallic recuperator for air preheating

Three nos. of Combustion Air Blowers (2W+1S) with VVVF drive have been envisaged for furnace.

Air Recuperator

A metallic recuperator will be installed in the flue channel to preheat the combustion air to about 550 oC. The recuperator will be cross-counter flow type. Dilution air fan & Hot Air Bleed will be provided for protection of recuperator.

Waste Gas Flue Exhaust System

Waste gases from furnace will be taken out through the opening provided on the charging end, and will be exhausted to atmosphere through underground tunnel with forced draft fan & chimney of adequate height.

4.3.3 HIGH-PRESSURE WATER PRIMARY DESCALER

Once the slabs have exited the reheat furnace, they will be transported via a roller table into a high pressure water descaling unit. During the reheating process an oxide layer (scale) will form on the slab, which, if not removed, will be rolled into the surface of the product causing surface defects and reduced product quality. In


order to ensure optimum product quality, the slabs are descaled to remove the oxide layer.

The process of scale removal will broadly consist four adjustable headers (two top, two bottom) with flat-jet nozzles delivering water at high pressure and suitable flows. Two of the headers will be operational and two of the headers will be standby. The headers are enclosed in a descaler hood to collect the water and scale. Chain curtain will be provided at entry & exit of the descaler. Main parameters of the primary descaler are indicate below :

Number on top headers : 2

Number of bottom headers : 2

Operating pressure : 240 bar

4.3.4 ROUGHING MILL AREA

The Roughing mill area will consist of a 4-high Reversing Roughing stand. A vertical edging stand will be provided at the entry side of each Roughing mill stand.

4.3.4.1 Vertical Edger

The Edger will be capable of taking a maximum draft of up to about 100 mm. It will be equipped with Hydraulic Automatic Width Control (HAWC) to permit quick width taper adjustments during rolling. Spindle change device for splined cardan shafts will be provided. The Edger will improve finished width tolerance, minimize plan view shape errors and enhance edge quality.

Parameters of edgers

Roll Diameter (grooved rolls) : 1200 / 1100 mm

Maximum roll separating force : 700 t

Maximum width reduction : 100 mm

4.3.4.2 Roughing Stand

The 4-high Roughing mill stand will be situated directly after the edger and the work rolls are driven by AC drive with two motors with ski control. Work roll bearings will be four rows tapered bearing. Back up roll bearings will be keyless type oil film bearings. Top backup roll will be hydraulically balanced by cylinder located in housing separator. For work rolls balancing, hydraulic cylinders will be located in maewest blocks. Back up roll balancing cylinders will be mounted on the top of the housing. Spindle of cardan shaft design


with spindle balance and spindle head holding device will be provided. Mill window liners of duplex material will be provided with greasing system, The stand will be provided with electro-mechanical screw down system and hydraulic roll force cylinders and control system. Two nos. of hydraulic roll force cylinders (one at operator side and one at drive side) will be mounted on the top of the mill window. Hydraulic roll force cylinders will be equipped with pressure and position transducers. The Automatic Gauge Control (AGC) in conjunction with roll allignment control will be provided to control thickness, wedge and camber. The roll force hydraulic cylinders will be fed by high pressure hydraulic system. Other hydraulic cylinders will be fed by low pressure hydraulic system. Roll cooling headers The entry and exit side of the stand will be provided with roll cooling headers. Hydraulically operated Entry guide ledges will be provided at each side of the stand to centre the slab. Mechanised Quick Work Change System will be provided for work roll changing. Back-up roll change is carried out by means of a hydraulic cylinder. The work rolls and the back-up rolls are placed by crane onto the roll transfer car which transports the rolls to the roll shop.

Oxide removal headers (top & bottom) will be provided at entry and delivery guides to direct water to top and bottom of the strip surface to remove oxide dust. Descaling headers will also be provided at the roughing stand.

Load cells will be installed between the sledge and the bottom back up roll chocks.

4-high roughing stand parameters

Mill configuration : 4-high

Work roll diameter : 1250 mm 1130 mm

Work roll barrel length : 2250 mm

Back-up roll diameter : 1600 mm 1440 mm

Roll separating force : 5500 t

4.3.4.3 Delay Table and Passive Cover

After the final roughing pass the transfer bar is transported along the delay table, which comprises the heat retaining passive cover system. Passive cover serves for saving temperature of the transfer bar and for reduced temperature drop between head end and tail end. Consequently, passive cover helps to achieve a smaller minimum strip thickness and more consistent final material properties. The passive cover will consist of a group of insulating


panel located on the delay roller table after the 4-high roughing stand. Each module of the passive cover can be lifted hydraulically. Suitable protection will be provided at the entry of the passive cover to protect it from the curved transfer bar ends.

4.3.4.4 Transfer Bar Reject System

Bar reject device will be provided between the roughing stand and the finishing stand to reject transfer bar, if required. The system will mainly consist of suitable nos. of pushing devices actuated by hydraulic cylinder. Rejected transfer bar, pushed of the rolling line, will be positioned on skid mounted supports aside the rolling line.

4.3.5 CROP SHEAR

Behind the passive covers, a drum-type crop shear will be provided to shear and square off the head and tail ends of the transfer bar. The crop shear will consist of drum housing, drums with shear knives, knife drums bearings and the drums AC drive system. Knives will be locked on drums with hydraulic quick unlocking device. The crop shear is equipped with a crop optimization system to minimize the yield loss.

The scrap produced will be disposed into scrap buckets via a chute. Hydraulically adjustable entry guide will be provided at the entry of crop shear to guide the transfer bar into the crop shear and keep it centered. Feed rollers will be provided at entry and exit of the crop shear.

Broad parameters of the crop shear are indicated below :

Shear Type : Start-stop Rotary Drum-type

Maximum bar cross section : 2,100 x 76 mm (API X 80)

4.3.6 FINISHING MILL AREA

4.3.6.1 Secondary Descaler

A secondary descaler alongwith pinch rolls will be provided before the finishing mill for descaling the transfer bar before entering into the finishing mill. The pinch rolls will drive the transfer bar through the water nozzles at uniform speed and will also stop water from flowing back on the transfer bar and prevent chilling.

The secondary descaler will consist of two nos. of top and two nos. of bottom headers with flat type nozzles housed in a spray hood, solenoid operated valves, etc. Descaling system pressure will be 200 bars (indicative). The spray hood will have flaps with replaceable


wearing plates driven by pneumatic cylinder to stop high pressure water from spray backwards.

4.3.6.2 Finishing Mill Train

The finishing mill will consist of six 4-high, fully hydraulic mill stands (F1F6). Finishing mill train will mainly comprise of the following facilities :

Guides

Entry and exit guides arranged ahead and at back of the stands afford guiding action to the strip as it passes the stands

Mill stands

Six nos. of finishing stands will be installed in the finishing mill. Each stand will be of 4-high configuration.

Mill drive with AC motors, reduction gear box and pinion stands will be provided. Cardan shaft/ geared spindles with spindle balancing and head holder will be provided. Work roll bearings will be four tapered roller bearing. Back up roll bearings will be keyless type oil film bearings. Top backup roll will be hydraulically balanced by cylinders mounted at the housing top. Work rolls will also be hydraulically balanced by cylinders mounted in Maewest blocks. Mill window liners of duplex material will be provided with greasing system. Two nos. of long stroke hydraulic roll force cylinders (one at operator side and one at drive side) will be mounted on the top of the mill window. Hydraulic roll force cylinders will be equipped with pressure and position transducers. The initial roll gap setting and automatic Gauge Control (AGC) is provided via hydraulic gap setting cylinders The roll force cylinders will be fed by high pressure hydraulic system. Other hydraulic cylinders will be fed by low pressure hydraulic system. Load cells will be provided between the sledge and the bottom back up chocks.

The finishing stands will use shaped work rolls (contoured rolls) with roll bending and shifting mechanism for control of strip profile and flatness for the strip. Hydraulic cylinders for positive work roll bending will be mounted in the Maewest blocks. The positive work roll bending cylinders will also serve for work roll balancing. Hydraulic cylinders for negative work roll bending will be mounted in back up roll chocks. Further, hydraulic cylinders will also be provided at the maewest blocks for work roll shifting.

Stripper will be provided at entry and exit of each mill stand so as to guide the transfer bar head and also to prevent the contact between the cooling water and the strip surface. These strippers will be


adjusted by pneumatic cylinders. The entry and exit side of the stand will be provided with roll cooling headers.

Quick Work Roll Change system will be provided for work roll changing in all the stands. Steel sledge for back up roll change will be located between the bottom back up roll chocks and the mill housing bed plate.

Work Roll cooling headers will be provided at entry and exit sides of each rolling stand. Work Roll Cooling header on the entry side will be located only in top position, while in exit side are located on top and bottom position. All headers will be mounted on guides. Backup roll header will be located on entry side on top position. Further, anti-peeling cooling sprays will be provided at entry side of the stands which will cool the strip in proximity of the roll bite to avoid damage of the chromium oxide of the work roll.

Roll bite lubrication will be applied at first four finishing stands to reduce friction and therefore to reduce separating force and limit roll wear. The roll bite lubrication system will premix and store a mixture of lube and water in right proportion to feed a spray system. This oil-water dispersion will be sprayed at the roll bite through auxiliary headers & nozzles. One no. of header will be provided at top and bottom work roll each. Each header will be divided into different spraying zones so as to optimize oil consumption as per the strip width.

The mill stands F1 to F4 are equipped with roll gap lubrication devices.

Parallel neck taper roller bearing alongwith, thrust bearing at the operator side will be considered. Keeper plate will be swevelling type mounted on shifting cylinder barrel. Pass line adjustments will be through shims.

Main parameters (Indicative)

Number of mill stands : 6

Mill configuration : Type 4-high

Work roll diameter (F1-F4) : 850 750 mm

Work roll diameter (F5-F6) : 720 620 mm

Work roll barrel length : 2550 mm

Back-up roll diameter : 1600 1440 mm

Back-up roll barrel length : 2250 mm


Back-Up roll bearing : Keyless oil-film type

Mill stand force (F1-F4) : 5000 t (max)

Max. mill stand force F5-F6) : 4000 t (max)

Drive Power : 10,000 kW

Work roll bending (each chock) : 200 t max ( F1-F4).

Work roll bending (each chock) : 160 t max (F5-F6).

Work roll shifting stroke : +/- 150 mm (max)

Maximum rolling speed : 20 m/s

Roll force cylinders max stroke : 200 mm

Inter stand loopers

Low-inertia hydraulic looper will be provided between the finishing mill stands to ensure constant strip tension between two successive stands and a stable rolling process. Hydraulic actuators will be directly connected to the loopers arms. Each looper system will comprise of a looper table assembly , idle roller, hydraulic cylinder & servo valve for tilting the looper table. Each looper will be equipped with two load cells, mounted at each side of the idle roll for measurement of strip tension at drive and operating side for the control of the strip tension and levelling control.

Oxide blowing system

Top and bottom spraying headers will be provided on mill stands delivery guides to direct water to top & bottom at strip surface close to the roll bite in order to avoid mill scale powder formation and consequently scale fume emissions.

4.3.7 RUN OUT ROLLER TABLE WITH LAMINAR STRIP COOLING SYSTEM

The run-out table will be provided downstream of the finishing mill and serves to convey the strip through the laminar cooling line. The run out roller table will have hollow rollers individually motor driven.

A run out laminar strip cooling system will be provided in the area of run-out table for cooling the strip down to the required coiling temperature in order to ensure the required metallurgical properties. The laminar strip cooling system is equipped with upper and lower cooling headers for cooling both the top and bottom strip surface. The run out cooling system will be a U-tubes banks on the top and


blanks of multiple nozzles headers on the bottom. Bottom strip cooling headers will also be utilized to cool roller table rollers. The header will be closed/opened by proportional valves according to the strip thickness, speed and temperature at inlet, so as to assure the metallurgical properties of the end product. The top headers can be hydraulically raised in emergency cases.

The laminar cooling section will have different zones so that different cooling strategies can be applied for various steel grades of the product mix. Different zones will work in combination with microstructure control model.

4.3.8 ROLLER TABLES

Roller tables at all locations will consist of roller tables frames, apron with guides, roll assemblies with individually driven AC drives, roller cooling system, and automatic bearing lubrication.

4.3.9 DOWN COILER EQUIPMENT

At the end of the run-out roller table, two nos. of down coilers with the pinch roll units will be provided for coiling the hot rolled strip.

A hydraulically operated side guide will be provided before each pinch roll unit to position the strip.

The pinch roll unit feeds the strip into the coiler and generates the strip tension required for the coiling operation. The pinch roll gap is set by position controlled hydraulic cylinders according to the relevant incoming strip gage. After threading the strip into the pinch roll gap, the cylinders are switched to pressure control mode to apply the necessary force to the strip (depending on strip gauge and material).

The coiler will be designed as a 3 or 4 hydraulically operated wrapper rollers with step control.

Pinch roll polisher will be provided for online polishing/grinding of pinch rolls.

Main parameters of down coilers (Indicative)

Type : 3 or 4 roller type, hydraulically actuated

Maximum coil weight : 35 t

Specific coil weight : 20 kg/mm


A strip catcher will be provided downstream of down coiler no. 2 to stop the strip head end for safety in case of failure of the pinch roll and down coiler. The strip catcher will consist of a steel curve chute and carry over apron.

4.3.10 COIL HANDLING AND TRANSPORT SYSTEM

From the coiler the coils will be removed by a coil car and transported to a coil banding station. One coil car will be provided for each down coiler. Traverse of the coil car will be through hydraulic motor. Elevation of the coil cars rollers will be done hydraulically. At the coil banding station, circumferential strapping of the coil will be done with the help of banding machine. An automatic coil marking unit will also be provided.

After this, the coils are transported to walking beam type coil conveyors. The walking beam coil conveyor will consist of a fixed supporting frame and a walking beam which through a rectangular motion, lifts and transfers the coil from one saddle to the next one. Coil tilters, lifting mechanism, turn table will be provided as necessary.

Sample collection and inspection station will be located at the walking beam conveyor. Coil will be picked up by a coil transfer car and positioned on the coil rotating rig. Sample will be cut with the help of robotic cutting arm.

Strapping station will also be provided along the walking beam conveyor. Circumferential and radial strapping of the coils will be done at the coil strapping station. A strapping machine will be provided each for circumferential strapping and radial strapping. The strapping machine will broadly consist of the machine car running on rails, strap chute, strap dispenser and pneumatic & hydraulic components. The strap dispenser will be actuated pneumatically.

A coil weighing station will be provided along the coil conveyor downstream of strapping station..

4.3.11 COIL STORAGE

The coils from the walking beam conveyor will be picked up by overhead cranes and placed in the coil storage yards. Coil saddles will be provided to support the coils and allow to dispose them on multiple rows. The coil storage yards will have the capacity to store the coils of one week production. Facilities for automated loading and storage will be provided in the coil yard.


4.3.12 SHEET SHEARING LINE

4.3.12.1 A Sheet Shearing Line of 400,000 tpa capacity will be installed within the proposed Hot Strip Mill Complex to produce sheets/plates from the HR coils produced. The sheet Shearing Line will be installed in a separate bay parallel to the coil storage bays. The sheets/plates produced through this line will be dispatched from the same bay (shearing line bay).

4.3.12.2 Main Parameters

Main parameters of the Sheet shearing Line are indicated below :

Inner dia of input coils : 762 mm

Outer dia of input coils : 1,2002,150 mm

Maximum coil weight : 35 t

Hot strip thickness : 5.0 - 25.4 mm

Hot strip width : 1000 - 2100 mm

Max. sheet length : 5000 mm

Maximum : 10 t

Maximum Line speed : 40 m/min

Max threading speed : 15 m/min

4.3.12.3 Description of technological facilities

The technological layout of the Sheet Shearing Line is indicated in Drawing no. CET RN 3379 RF1 00 004 R=0.The input coils will be placed onto the coil loading skids by overhead crane. Three skids will be provided for storing the input coils to be fed to the pay-of reel. From the skids, a coil car will pick up the coil and will transport to the payoff reel. The pay-off reel and processor roll are equipped with a strip centering control system for proper centred strip guiding within the line. The two pressure rolls will be used for the strip threading as well as to prevent back-turning of the pressure roll due to back-pushing of the strip during coil opening procedure. The processor roll will be used for threading and processing during strip unwinding, horizontally and vertically adjustable as a function of strip gauge and material strength A pinch roll unit will transport the strip to the leveler and also provide the required strip tension. The pinch rolls will be hydraulically adjusted in accordance with strip thickness, strip width and material strength. Side guides will be provided before the leveler.


Two multi roll strip levelers will be provided to improve the flatness of the strip. The strip leveller will be equipped with multiple levelling rolls, backed-up by supporting rollers. Top levelling rolls are adjustable under levelling load by means of hydraulic cylinders. Hydraulic adjustment of the top levelling rolls is provided with super-imposed levelling gap control. Compensation of the crossbeam deflection is provided by means of a pre-bending system for the top levelling rolls. With the pre-bending system better levelling results of plates with wavy edges or centre buckles can be achieved. Individually adjustable bottom rolls are provided in order to allow the required shape of the levelling gap to be obtained as a function of strip gauge and material strength.

The strip, after leveler, will be fed to the flying cross cut shear through pinch rolls. Cutting of strip through the flying shear will be achieved mechanically by a flywheel. The top blade will be fixed and bottom blade moves up and cutting method will be downside up Gap between the blades can be adjusted by motor. Change of blades will be done by cartridge mode extraction of blade holders. Two measuring rolls coupled with encoders will be provided for measurement of length for shearing action. An expandable runout conveyor will be provided to co-ordinate the motion of the flying shear with the line. This will be a driven by AC motor belt type conveyor. The conveyor will automatically adapt its length to the motion of the flying shear.

A paint marking machine will be provided for marking the finished plates during transfer on the roller table to the piler.

The piler will comprise of two piling positions and will be arranged for automatic plate pile changing for plates up to eight meter length. Another piler will be provided for stacking rejected sheets. The Piler will be provided with tiltable roller conveyors for providing straight-sided plate piles in longitudinal direction. The piler will be equipped with stops for head and tail end of the plates for proper piling. Two hydraulically operated lifting tables will be located under the piler. Two separate pile transfers will be used for transport of the plate piles from the two piling sections to the discharge roller table. Two lifting tables will hand over the packages from the pile transfers to the discharge roller table sections. The pile weighing system will be incorporated in the discharge lifting tables. The weighing system incorporates a weight card printer and a data memory for data transfer. Discharge roller tables will be provided for further transfer of the piles. Mechanised strapping system will be provided to make the packets.


4.3.13 ROLL SHOP

A Roll Grinding and repair shop will be provided adjacent to the proposed Hot Strip Mill. The roll shop will be utilized to grind the work & back up rolls of the new mill, grinding of the shear blades, repair of the bearings and other associated services. The Roll shop will comprise of the following main facilities :

- CNC Roll Grinders (5 nos.)

- Roll cooling stands

- Roll handling tackles for handling single/double rolls with chocks

- Back up and Work rolls chock extractors (2 nos.)

- Roll chock tilter

- Back up roll chock washing station with high pressure hydro washer

- Work roll chock & bearing cleaning tank

- Roll washing machine

- Set of roll racks

- Rack for grinding disks

- Storage rack for knives

- Jib cranes at required locations.

- Set of instruments including, Portable digital thermometer, Portable internal & external micrometers, Filler gauges, Depth gauges, vernier caliper, BUR neck taper measurement gauge-Bevel measurement, Portable Ultrasonic Crack Tester Portable Hardness tester Portable Roughness tester

All the roll grinding machines will be CNC controlled. Out of the total 5 grinding machines, three will be designed for grinding finishing stands work rolls, shear knives and edger rolls. Balance two will be designed for grinding Finishing mill back up & work rolls and Roughing stand back up & work rolls. Grinding of work rolls can be performed with chocks with the rolls.

A workshop will also be provided with adequate numbers of machine tools.


4.3.14 EOT CRANES AND MATERIAL HANDLING

Overhead EOT cranes will be provided at different locations of the Hot Strip Mill as indicated below :

Slabs Yards : 4 nos. (2 in each bay)

Furnace Charging : 2 no.

Furnace bay : 1 no.

Mill bay : 3 nos.

Roughing stand motor bay : 1 no.

Finishing stands motor bay: 1 no.

Coil storage & dispatch bays: 6 nos. (3 nos. in each bay)

Sheet Shearing Line & dispatch: 3 nos.

Roll shop : 3 nos.

Scale Pit : 2 no.

Suitable handling facilities will be provided at other auxiliary areas including pump house, compressor, etc.

Two transfer cars will be provided between the mill bay and the roll shop for inter bay transfer of rolls. A transfer car will also be provided between mill bay to motor house.

4.3.15 HYDRAULICS & LUBRICATION

4.3.15.1 Oil-Hydraulic System

Broad details oil hydraulic system will be as below:

i) The flow and pressure for the systems will be selected by the Bidder, based on the system requirement.

ii) Filters used will be duplex type with electrical clogging indicators. rating of the filters will be as per system requirement. ratio will be 200. Flow capacity of pressure line filters will be 2 times the maximum flow rate of pumps and flow capacity of return line filters will be 3 times the total flow rate of pumps.

iii) Mineral oil will be used. iv) The tank capacity will be minimum 5 times the capacity of

main pump.


v) The different velocities to be considered for the system will be as below:- For suction lines 1.0 m/s (maximum) For pressure lines 5.0 m/s (maximum) For return lines 3.5 m/s (maximum)

vi) For the pipelines, size up to DN 30, inside diameter will be as per DIN 2391/C. Connection will be by welding cone screw coupling with O-ring seals according to DIN 2353. For sizes above DN 30, inside diameter will be as per DIN 2448 and will be connected by flanges. Pipelines and fittings will be as per system requirement.

vii) The air breathers will be desiccant type. viii) The system will be designed with oil level monitoring in the

tank, pressure monitoring in the system, temperature monitoring etc.

ix) The Power Pack will be provided with tray at the bottom for taking care of leakage of oil.

x) Off-line filtering-cum-cooling system will be provided. Capacity of pump (lpm) will be 1/10th of tank capacity

xi) The number of standby pumps will be as below:

Number of normally operating pumps

Number of standby pumps

1 - 4 1

5 - 8 2 4.3.15.2 Grease Lubrication System

Broad details for Grease Lubrication System will be as below:

i) Centralised motorised dual line grease lubrication system

ii) The system will be 1 No. working and 1 No. standby for main pumps with reservoirs, filters, relief valves, change over valves etc.

iii) Refilling pump, main pumps, change over valves will be electric motor operated.

iv) Pipe sizing will be carried out based on actual pressure drop calculations. However, minimum pipe sizes will be as below:

Pipe Zone Pipe OD (mm) x pipe thickness

(mm)

Material of pipe


Pipe Zone Pipe OD (mm) x pipe thickness

(mm)

Material of pipe

Main header 30 x 3 DIN 2391 C

Branch lines from main header up to inlet of distributors

20 x 2 DIN 2391 C

Feed lines from distributors up to inlet of bearing points

10 x 2 DIN 2391 C

v) The system will be operated based on end pressure relays as well as timers.

vi) Reservoirs for main pumps will have minimum capacity of 100 litres.

vii) 1 No. grease refilling pump with provision of easy taking out or putting in of the refilling pump inside the barrel, like provision of a hand operated winch, will be provided.

viii) Operating period will be considered as 24 hours per day.

4.4 UTILITY FACILITIES

4.4.1 Compressed Air System:

Compressed Air will be required for pneumatic valve actuation, camera cooling etc for furnace and mills as well as for furnace oil atomization in the furnace. The approximate requirement for the same will be

Mill including Reheating Furnaces - 1000 Nm3/h

Furnace Oil atomization - 5000 Nm3/h

The compressed air for oil atomization will be utilized occasionally when furnace will be fired by furnace oil. Above mentioned requirement for Compressed Air will be tapped from the grid near the old HSM. The compressed air system will be complete with driers and compressed air piping to different consumers

4.4.2 Fuel Oil System

For normal operation Furnace will be fired by Mixed Gas. However in case of occasional gas shortage the Reheating Furnace will also be


capable of firing through Furnace Oil. Furnace oil for the purpose will be brought from old HSM through pumping. For this purpose a furnace oil pump house will be installed at old HSM. To maintain the flow ability of furnace oil electric tracing of oil pipelines have been envisaged. A day tank of 100 kl capacity will be installed in the new HSM along with oil supply system to the Reheating Furnace.

4.4.3 Other Utilities

Nitrogen for purging of gas line will be tapped from existing DN600 header near column no. B-71. Oxygen required for general purpose cutting etc at a pressure of 18-20 bar will also be tapped near column B-71. All the utility pipelines will be laid on new trestles as there are no existing utility pipe supporting system available between old HSM & new HSM.

4.5 WATER SYSTEM

4.5.1 The water system envisaged for various requirements of proposed Hot Strip Mill (HSM) will be re-circulating type and will be designed with zero discharge concepts. Only make-up water will be taken from the existing Lagoon of RSP with adequate treatment and pumping facilities. The proposed water system for the Mill will consist of following types of water systems: 1. Reheating Furnace Cooling Water System 2. De-scaling Water System 3. Mill Equipment Cooling Water System 4. Laminar Cooling Water System 5. Strip Cooling Water System 6. Mill Auxiliaries & Motor Cooling Water System 7. Make-up water system 8. Cable tunnel dewatering facilities

All critical equipments and equipments related to contaminated scale water will have 100% standby. Other equipments like cooling tower, heat exchanger, filters, settling tanks, water softeners will have minimum one standby.

All underground pipes will be routed through ventilated and illuminated pipe cellars with adequate space for inspection and future pipe replacement.

All pumping stations and equipment buildings will have pendant operated handling facilities like cranes/ hoists.


All cooling towers will be of RCC structure, over-ground basin, FRP fan and covered hot water basin. Cooling towers of each circuit will have 10% side stream filtration facilities.

All auto control valves will be electrically operated gate valves and all manual valves more than DN300 size will be gear operated.

There will be common maintenance workshop with adequate working space and a small manufacturing area with basic machines like centre lathe, drilling machine, power saw, bench grinding, welding etc.

At present, the makeup water pipe line of size DN250 is going underground to SGP through the proposed HSM area. This line is to be suitably rerouted without affecting production of SGP.

Each water circuit will have flow, pressure, temperature measurements and also have indication in the main control room.

All water tanks/sumps will have adequate manual cleaning facilities.

Wherever applicable, the on-line type quality monitoring instruments like pH meter, Turbidity meter, TDS, Hardness etc. to be provided.

4.5.1.1 Reheating Furnace Cooling Water System Soft water is envisaged for skid cooling of the Reheating Furnaces. The envisaged flow rate is 1600m3/h at a pressure of 40mWC at the consumer end. It is proposed to install a dedicated Soft water generation & re-circulation system for the proposed Reheating furnace with all its associated facilities like Soft Water Plant, Soft water sump, Emergency overhead soft water tank, Chemical dosing unit, Pumps, filters, heat exchangers, pipes, valves, fittings, instruments etc. However, 100% standby soft water plant and soft water pumps are envisaged. A Pipeline will be laid from the Pump delivery header, installed in the Mill Pump House upto the Reheating furnace header with all valves and fittings. After cooling the skids, the hot water will be returned to the heat exchangers for cooling. A water filter will be provided in the supply line to ensure that no foreign material enters the water-cooling elements. Makeup to this re-circulating system will be taken from the proposed Soft Water Plant. The industrial water required for Soft Water Plant will be tapped from the proposed makeup water network. To take care the emergency situation arising out of pump failure or power failure, an Emergency Overhead Water Tank is envisaged to supply cooling water for half an hour. Provision of emergency power supply will also be there.


Industrial water is envisaged as secondary water for heat exchangers. A separate water system (industrial quality) is to be installed for the purpose with all its associated facilities like Pumps, Cooling tower, filters, valves, pipes, fittings etc. A Pipeline will be laid from the Pump delivery header, installed in the Mill Pump House up to heat exchangers and from heat exchangers to top of the cooling tower to carry hot water from Heat exchanger with all valves, fittings, instruments etc. The makeup water required for re-circulation cooling water system will be tapped from the proposed makeup water network. Filtered water is envisaged as cooling water for direct cooling system of reheating furnace. The water will be tapped from delivery header of filtered water pumps.

4.5.1.2 De-scaling Water System

Filtered water is envisaged to be used for de-scaling purpose. De-scaling system for roughing mill and finishing mill will be at different pressure. The envisaged flow rate for roughing mill is 700m3/h at a pressure of 2400mWC and for finishing mill is 120m3/h at a pressure of 3800mWC. A Common Filtered Water system is to be installed for the purpose with all its associated facilities like Settling tank, Settled water sump, Settled water pumps, Pressure filters, Filtered water sump, Filtered water pumps, Cooling towers, Duplex water filter, valves, pipes, fittings, instruments etc. Two groups of pumps will be installed, one group will consists of settled water pumps to supply water to Pressure filters and other group will consist of filtered water pumps to supply water to De-scaling system through filters. Return water from de-scaling system will go directly to the settling tank through scale channel. Arrangement for removal and transportation of mill scale and oil from scale pit and settling tanks will be there. The makeup water required for re-circulation water system will be tapped from the proposed makeup water network.

Air blowers and filter backwash pumps are envisaged for backwashing of pressure filters.

4.5.1.3 Mill Equipment Cooling Water System Mill Equipment consists of two parts, one is high pressure (HP) roll cooling and other is low pressure (LP) roll cooling. Filtered water is envisaged as cooling water for Mill Equipment. The envisaged flow rate at the consumer end is 2070m3/h at a pressure of 120mWC for HP Roll Cooling and 1730m3/h at a pressure of 60mWC for LP Roll Cooling system. For HP roll cooling filtered water will be pumped from the common filtered water sump by a group of pumps with associated piping, instruments etc. For LP roll cooling, water will be tapped from de-scaling water circuit. Return water from Roll Cooling will go directly to scale channel for scale flushing.


Two groups of pumps will be installed for scale flushing, one group will consist of flushing water pumps to supply water for scale flushing and other group will consist of scale water pumps to transfer water from scale pit to settling tank. MOC of scale water pumps will be of abrasive resistant material of minimum hardness 600 BHN and MOC of valves, fittings will be of wear resistant material. Scale water pumps will have two parallel headers up to settling tanks each having 100% capacity to facilitate repair. Scale water channels, pipes will have inside coated with abrasive resistant basalt/ ceramic linings. The envisaged flow rate at the consumer end is 100m3/h at a pressure of 45mWC for scale flushing. The makeup water required for re-circulation water system will be tapped from the proposed makeup water network.

4.5.1.4 Laminar Cooling Water System Filtered water is envisaged to be used for Laminar Cooling. The envisaged flow rate is 6760m3/h at a pressure of 5mWC at the consumer end. Filtered water will be tapped from the common filtered water sump. The system will consist with all its associated facilities like pumps, filters, valves, pipes, fittings, instruments etc. Return water from the system will go directly to a common sump through suitable water channel. The common sump will collect return water from both laminar cooling & strip cooling system. From the sump water will be pumped to settled water sump through solid separator. The makeup water required for re-circulation water system will be tapped from the proposed makeup water network.

4.5.1.5 Strip Cooling Water System Filtered water is envisaged to be used for Strip Cooling. The envisaged flow rate is 1150m3/h at a pressure of 150mWC. Filtered water will be tapped from the common filtered water sump. The system will consist with all its associated facilities like pumps, filters, valves, pipes, fittings, instruments etc. Return water from the system will go directly to a the common sump through suitable water channel and from the sump water will be pumped to settled water sump through solid separator. The makeup water required for re-circulation water system will be tapped from the proposed makeup water network.

4.5.1.6 Mill Auxiliaries & Motor Cooling Water System Industrial water is envisaged as cooling water for Mill Auxiliaries and Motor cooling. The envisaged flow rate is 500m3/h at a pressure of 35mWC. For this Cooling Water System water will be tapped from cooling tower of secondary water circuit of heat exchanger cooling. Only one group of pumps is to be installed for the purpose with all its associated facilities and piping. A Pipeline will be laid from the Pump delivery header, installed in the Mill Pump House up to the consumer points with all valves, fittings, instruments etc. Return water lines will


be laid from consumer points to top of the cooling tower to carry hot water.

4.5.1.7 Make-up Water System Make-up water is required for all re-circulating water systems. Estimated make up water requirement for the proposed mill will be to the tune of 1000m3/h. The required makeup water will be available from the existing Lagoon of RSP. Lagoon water will be treated to industrial makeup water quality and pumped to an overhead makeup water tank at proposed Mill area. Adequate treatment facilities have been envisaged. All industrial makeup water consumers will avail water from the proposed makeup water tank through a suitable piping network. The water treatment plant will be installed on the space available in between the Lagoon and National Highway. Area requirement will be to the tune of 100x200m, which will be developed accordingly. The electric power requirement will be to the tune of 1000kW maximum demand & 1750kW connected load. The quality and other parameters of Lagoon water is as specified below:

pH 6.98 7.8

TSS 108 - 794 ppm

Oil & grease 2 4 ppm

Iron 2.5 4.2 ppm

Ammonical nitrogen (NH3-N) 4.8 15.5 ppm

Phenol 0.05 0.09 ppm

Cyanide 0.05 0.2 ppm

BOD 10 18 ppm

COD 44 92 ppm

Water temperature 32 oC

Tapping point Near discharging point from Lagoon.

Distance between Tapping point and proposed Mill

1500m. approx.

Proposed make up water pipe routing

Underground along the existing and proposed road

Make up to soft water system will be provided by a new soft water plant through a soft water storage tank. For soft water plant, industrial water will be tapped from the proposed makeup water line


and supply water to soft water plant through adequate pipe size for smooth operation of the soft water system.

For industrial water system make-up water will be tapped from existing makeup water ring main and supply water to Cooling Tower basin. The water flow will be controlled by the level of cooling tower basin.

For direct water (filtered water) system make-up water will be supplied to Filtered water sump. The water flow will be controlled by the level of the sump.

Each makeup water consumer will have a venturi/ orifice type flow transmitter in the line with flow indication in the main control room.

4.5.1.8. Cable tunnel dewatering facilities

For dewatering the underground cable/pipe tunnel 12 no pits will be provided with 12nos sump pump sets alongwith pipes, hoses etc. The water from cable/ pipe tunnel will go to the recovery water tank.

4.5.2. Control Philosophy

The cooling water system will be fully automatic with PLC. However, facility for local start/stop will also be provided for each individual drive. All electrically operated valves will have position indicator.

There will be one main control room for all water systems with all operational parameters, warning signals, instrument readings etc. will be displayed. There will be local operation stations also. MMI with display monitors will be installed in main control room for continuous display, monitoring and recording of all the important parameters of water systems.

4.6 AIR CONDITIONING & VENTILATION SYSTEM Following types of Air Conditioning & Ventilation System are envisaged for proposed Mill:

4.6.1 Chilled water based Central Air Conditioning system will be installed in a central AC plant building for various Control Rooms, PLC rooms, MCC rooms housing intelligent MCCs, digital drive rooms, weighing electronic rooms, Office Spaces, etc. The proposed Chilled water system will consist of the following major equipment: 1) Water cooled chiller units with accessories 2) FRP cooling towers for closed circuit condenser cooling

system


3) Necessary chilled water pumps (with 100% stand by), Condenser cooling pumps (with 100% stand by), piping, valves, etc.

4.6.2 Dry pressurized ventilation system will be installed for switch gear rooms and MCC rooms having non-intelligent MCCs.

4.6.3 Push-pull type ventilation system will be provided for cable tunnel/cellar and cable basements.

4.6.4 Exhaust ventilation system will be provided for compressor house, battery rooms, chiller plant room, transformer rooms, pump houses, store, toilets, etc.

4.7 FIRE FIGHTING SYSTEM 4.7.1 A comprehensive fire fighting System has been envisaged for entire

area of the Hot Strip mill. It consists of the following:

Portable Fire Extinguishers as first aid Fire Fighting System Water based Fire Fighting System Automatic Fire Extinguishing System i) High Velocity Water Spray System(HVWSS)/ Medium Velocity

Water Spray System (MVWSS)

ii) Gas based Fire Fighting System

Passive Fire Protection 4.7.2 Portable Fire Extinguishers

Portable fire extinguishers will be provided as per TAC norms to all the covered area in the HSM. This includes but not limited to new buildings, shops, electrical rooms, cable vaults, ventilation shafts, junction houses.

4.7.3 Water based fire Fighting System 1) A pump house will be provided to accommodate the envisaged

for fire fighting equipments, like electrically operated main fire pumps, diesel driven 100% standby diesel engine driven pumps, two jockey pumps i.e. working as well as standby, envisaged in this package. The minimum pumping capacity of the main fire water pump has been envisaged as 546m3/h. These pumps are complete with all accessories as per TAC norm. The facilities for automatic starting, stoppage and interlocks of the pumps will be provided depending upon the line pressure. A material handling facility like under slung crane will be provided. An electrical control room will be provided to accommodate the control panel along with electrics. A covered tank with a partition wall will be provided for storage of fire water for two hours of pumping


capacity. The line pressure should be kept as per TAC norm however it should not less than 8.8 Kg/cm2. Water will be tapped (DN150) from the proposed makeup water line. The facilities will be provided for refilling of fire water to both the compartments of the tank with the level switches and motorized valves. The tapping point will also be provided with gate valve for isolation.

2) Ring main based pipe header (DN300) to be provided to entire HSM area along the road to cater the fire water requirement. External hydrant will be provided for ever 45m spacing whereas internal hydrants will be provided at every 30m spacing. Every landing platform will be provided with landing valves. Each internal hydrant will be provided with hose box complete with two numbers of fifteen meter hose, coupling, nozzles. The underground pipeline will be provided with wrapping and coating as per IS to protect it from corrosion..

3) Manual type water spray system will be provided in the entire length of conveyor galleries. Each conveyor gallery will be divided not more than 50m segment for water spray. Each segment will be fed water from the riser connected to the Fire water header. A gate valve will be provided to each riser for isolation.

4.7.4 Automatic Fire Extinguishing System 1) High Velocity Water Spray System (HVWSS)/ Medium Velocity

Water Spray System (MVWSS): High velocity water spray system(HVWS) for transformers (above 10

MVA or having oil more than 2000 lt.) and Medium velocity water spray system (MVWS) for cable tunnels/cable galleries/ cable cellar/ cable vaults etc in the HSM complex. These system will be automatic and controlled by delude valve.

2) For protection of Computer rooms/ PLC rooms/ important Critical Control rooms including false floor and false ceiling, automatic clean agent fixed fire extinguishing system (IG-541) will be provided. The system will be designed according to NFPA 2001. 100% reserve cylinders filled with gas and accessories will be provided for all systems. There will be provision for switch over from main to reserve cylinders automatically from the panel as well as through toggle button.

4.7.5 Passive Fire Protection Fire Retardant Compound and Fire Barriers will be provided in electrical cable runs as passive fire protection. The compartmentalization of cable tunnels will be done as per IS:12459-1988. Fire check doors will be provided at each compartment.

4.8 INSTRUMENTATION, PROCESS CONTROL & AUTOMATION The Control and Automation systems are envisaged to provide complete control and monitoring of the following proposed areas.


The areas to be covered will be broadly consist of Slab Yard, Reheating Furnaces, Roughing Mills, Passive Heat Shield, Crop Optimization System, Finishing Mills, Cooling, Coilers & Coil Conveying Systems, Coil yard, Roll Shop, Hydraulic Systems, Drive Systems etc. Various process of Hot Strip Mill will be controlled by the operator from the respective Control Pulpits housing Control Desks, HMIs, CCTV monitor, Display and Alarm devices, etc. In order to monitor and control the complete process of Hot Strip Mill in an integrated way all process control equipment at Level-0, Level-1 & Level-2 will be fully integrated to form a unified control system transparent to the operators. The system will be reliable, efficient, less maintenance oriented, and easy to operate. Level-3 Manufacturing Execution System (MES) will be executed at HSM to manage manufacturing information. The MES will integrate all the functions and services, customers need for sustained maximization of the plant performance.

4.8.1 Level of Automation The proposed system will be based on micro-processor based network compatible field instruments with hierarchical control philosophy consisting of field instruments, field sensors, electro-pneumatic control valves, electrics, final control elements, gauges etc. at Level-0 , Process Control Systems consisting of multi-processor based Technological Control Systems (TCS) with Data Acquisition System (DAS) at Level-1. Material tracking from Slab yard to Coil yard will be part of automation system. Process Optimization Servers for Slab yard, Furnace, Roughing Mill, Finishing Mill, C

FR(R=0) 3379 for HSM RSP

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