bhushan power & steel ltd

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2011 Bhushan Power & Steel Ltd. Navdeep Lakhera [TRAINING REPORT-BHUSHAN POWER & STEEL LTD.] Six weeks industrial training from 25 june 2011, at Bhushan Power & Steel Ltd.

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2011

Bhushan Power & Steel Ltd.

Navdeep Lakhera

[TRAINING REPORT-BHUSHAN POWER

& STEEL LTD.] Six weeks industrial training from 25 june 2011, at Bhushan Power & Steel Ltd.

COMPANY PROFILE

Bhushan Power & Steel Limited, a fully integrated 1.5 Million TPA Steel

making Company with turnover of INR3873 Crores (USD 950 Million)

and 7 World Class ISO 9000 Certified State of the Art Plants at

Chandigarh, Derabassi, Kolkata and Orissa in India.

A leading manufacturer of flat, rounds and long products including value

added products with total steel value chain right from Coal Mining,

Billets, HR Coils, Pig Iron, CR Coils, GP/GC, Precision Tubes, Black

Pipe/GI Pipe, Cable Tapes, Tor Steel, Wire Rod and Special Alloy Steel.

Successfully commissioned 1.5 Million TPA Greenfield Steel and Power

Plant in Orissa with HR Coil making facility

—First in Private Sector in the State of Orissa. For the Orissa plant,

technology and equipments are procured from world-renowned

companies like Lurgi from Germany, ABB Ltd., SMS Demag, Siemens

etc. Bhushan is selling its Value added range of products in Secondary

Steel through a large distribution network in India (comprising more than

35 sales offices) and Abroad.

A rock-solid foundation combined with continuous up gradation and

innovation has ensured that we have constantly surpassed our goals.

Our end-to-end portfolio offers a wide spectrum of products with

consistently superior quality. In addition to our export thrust, we supply

to fast-growing sectors like automotive, white goods, construction,

furniture, fasteners, telecommunication, etc.

COMPANY OVERVIEW

Commenced operations in 1989 with a capacity of 60,000 tons & a

turnover of USD 11.24 million.

Transformed to 3rd largest producer of Cold Rolled Steel after Steel

Authority of India (SAIL) & Tata Steel with an installed capacity of one

million tons and sales of more than USD 1 Billion.

Focused on niche high value added segment of automobile and white

goods & is today a leader in these segments. Recently started the

country’s largest Colour Coated line and first to manufacture the

Galume (zinc and aluminum coated sheets / coils).

Principal production facilities at Sahibabad, Uttar Pradesh, Khapoli,

Maharashtra and Dhenkana in Orissa (scheduled to be completed in

July 2009.

Invested in latest technology/ equipment without compromising over

cost.

First to set up a high tech plant in 1996 to cater to automobile and

white good sector, in technical tie-up with Sumitomo Metals, Japan.

BSL has a good debt-servicing track record.

Profit making and dividend paying company since inception.

RAW MATERIAL SOURCES

The company processed mild steel (MS). It receives raw material

from various sources:-

• B.S.P (Bokaro steel plant)

• R.S.P (Rourkela steel plant)

• Tata steel plant

• Essar

• The sizes of raw material ranges from 5.5 to 6mm thickness, 920

to 1600mm width.

TYPES OF RAW MATERIAL

• Mild Steel

• D (Drawing-0, 08 to 0.1 % carbons)

• DD (Deep Drawing -0, 06 to 0.08% carbon)

• EDD (Extra Deep Drawing -0.04 to 0.06 % carbon)

• O (Others – 0.12 to 0.13 % carbon)

• CS – 11 (Above 0.18 %)

VARIOUS PROCESSES

The various processes deployed at the Industry in cold rolling of steel

are:

• H.R. SLITTER (Hot Rolled Slitter)

• C.B.L. (Coil Build up Line)

• Pickling

• Cold Rolling Mill

• Rewinding

• Annealing

• C.R Slitter (Cold Rolled Slitter)

• CTL (Cut to length)

• Packing & Dispatch

H.R SLITTER (HOT ROLLED SLITTER) • This machine is used for slitting or cutting the hot rolled coils which

have been received as raw materials from various sources such as

Tata or Sail Bokaro. Initially, the hot rolled coils have width up to

1550 mm. The rolling mills which are set up in the plant cant roll

such wide coils. The width of the hot rolled sheet (Raw materials)

is decreased or the sheet is slit into two or three rolls, as the

requirement of the customer may be. The maximum width of the

coil that can be cut is 540 mm and minimum is 200 mm.

• Raw materials received have width up to 1550mm (approx.).

• Diameter of ring cutter is 395mm.

• Material of the cutter is high speed steel.

Parts of H.R Slitter

1. Coil stand

2. Coil car

3. Pay off stand

4. Uncoiler

5. Sunnbber

6. Feed table

7. Leveler

8. Pinch roller

9. Shear

10.Guide

11.Cutter slit

12.Loop pit

13.Tension rolling

14.Re coiler

HOT ROLLED SLITTER

COIL BUILD UP LINE (CBL)

• In CBL extra sheet is welded at the beginning and at the end of the

coil called the Leader and Tail end respectively. This strip called

Leader End is about 3 meters in length. This is done to increase

the yield of coil during rolling because initially some sheet is taken

in some initial rounds in rolling and thus the starting and ending

part of the coil cannot be rolled properly.

• Leader End is added to the coil to save yield and prevent wastage.

• Coil bend and damages in HR slitter are inspected here.

Parts of CBL

1. Uncoiler

2. Feed table

3. Leveler 1

4. Shear

5. Clamping Plate

6. Welding

7. Guide

8. Pressure Pad

9. Leveler 2

10.Tension rolling

11.Recoiler drum

PICKLING PROCESS

• The H.R coils as raw materials are somewhat rusted. They contain

oxide scales on their surface containing chemical compounds like

iron oxide FeO, Fe2O3 and Fe3O4.

• So as to improve the surface finish and to remove these oxides

pickling process is undertaken.

• Acid used is HCL.

• Coil is passed through 3 acid tanks, after that through 3 water

tanks.

• The acid proportion in first tank is 3 to 5% and in the second tank

is 7-10 % and in the third tank is 12 to 15 %.

• HCl used is dilute. Dilution varies from tank to tank.

• Coil is dried with hot air dryers and cold air blower.

• The temperature of the HCL ranges from 58 to 68 `C.

• Finally after sprinkled by rust preventive oil, it is finally recoiled at

the recoiler end.

• Parts of line are Acid tank, Uncoiler, feed table, Shear, Heat

exchanger, Water tank, Dryers, Tension trolling and Recoiler drum.

COLD ROLLING MILL

Cold rolling is a metallurgical process in which metal is passed

through a pair of rollers at a temperature below its recrystallization

temperature. This process hardens the metal, by compressing and

stretching the metal. There are two rolling mills namely Mill 1 and Mill

2. ln mill 1 coil of 545mm maximum width and mill 2 coil of 465mm

maximum width can be cold rolled. In both the mills there are 2 work

rolls and 2 backup rolls. Diameter of work roll is 210mm and Diameter

of backup roll is 550mm.

Cold rolling is done to reduce the thickness of the coil. The range of

the thickness reduced in the plant is from 3mm to 0.28mm. The

thickness obtained finally is according to the requirement of the

customer. The mill is operated by programmable logic controllers.

There is an operator assigned to each of the two mills. The operator

feeds various parameters into the system and then the process

proceeds automatically. The coil is first loaded into the pay off roll.

From here it passes to the entry tension roll and then it passes to the

delivery tension roll via the working rolls where it recoils. The tension

to the backup rolls is given by the hydraulic cylinders which then

transmit the load to the working roll which further transmits the load to

the sheet. There is 20 to 30 % reduction in thickness of the coil in one

pass. Non contact gauges are used in these mills which measure the

thickness of the sheet. The recoiling and uncoiling process takes

place at both entry and delivery tension roll. A coolant named as aqua

roll is also used.

1. Saddle table – it is actuated with the hydraulic cylinders help to feed the

strip into the leveler.

2. Bridle roller – these are used to release the tension in the strip and are

made of iron over which rubber is wrapped . there are two bridle rolls

when the speed of bridle rolls is more than recoiler then it will loosely

wrap over the recoiler drum.

3. Recoiler drum – this is the drum on which the slitted coil are recoiled

4. Tachogenerators –it sis used to control the speed of motor.

5. Hydraulic Power pack – it provides the oil to hydraulic system. There is

pump and directional valves. PC valves are used to control the supply of

oil.

Defects occurring during rolling process --

Roll mark

Soft mark

Skidding mark

Folding mark

Roll crack mark

Scratch mark

HISTORY

Growing from strength to strength

1970 - Started with very small initial outlay for manufacturing Door Hinges & later on, Rail Track Fasteners.

1973 - Manufacturing facilities set up for Tor Steel and Wire Rod in Chandigarh.

1981 - Rolling Mill Project commissioned at Chandigarh for Round and Narrow Strips.

1985 - Backward Integration Project for Steel Melting facilities.

1986 - Upgrading of Mini Steel Plant with continuous casting and ladle furnace facilities. 1997 - Commissioning of Narrow Width Cold Rolling Project at Chandigarh.

1998 - Commissioning of Precision Pipe Project at Chandigarh.

2001 - Commissioning of Cold Rolling & Galvanizing Complex at Kolkata.

2002 - Addition of narrow width Cold Rolling facilities at Kolkata.

2003 - Expansion of wide width Cold Rolling facilities, ERW Water Pipes & Tubes down stream facilities at Kolkata.

2004 - Further expansion of Cold Rolling facilities at Kolkata.

2005 - Commissioning of Orissa Project consisting of 4 DRI Kilns, Steel Making Facilities, Coal Washery and 100 MW Power Plant.

2007 - Commissioning of further expansion of Orissa Project consisting of HR Coil Mill, Steel making, Blast Furnance, Sinter plant, Coke oven plant, Oxygen plant and Lime & Calcining Plant.

2008 - Implementation of further expansion in Orissa Project in progress. Consisting of DRI Kilns, Coal Washery, Coal Mining, Power Plant & Steel Making facilities.

Annealing

During cold rolling of the coil, the density of imperfections and

dislocations increases. These imperfections have strain energy

associated with them. On annealing , metal tenda to loose excess

energy acquired during cold rolling and revert back to initial stage.

The general purpose of annealing is to reduce hardness, facilitate

machining and to relieve internal stresses.

This heat treatment process is given to the metal so as to achieve one

or more of the following objective:

To relieve the grains and provide homogeneous structure

To relieve internal stresses set to cold rolling

To soften the metal and thus improve its machinability

To effect changes in some mechanical, electrical and magnetic

properties.

To prepare further treatment or processing

Here only full annealing takes place, and we have 9 furnaces, 9

cooling hoods, 18 covers and 16 bases.

Base - on which coil with cover , cooling hood and furnace is

placed.

Cover – which covers the coil after the coils are loaded on the

basis.

Technical specifications of annealing furnace

Equipment - HSD fired type bright annealing furnace

Charge material - Cold rolled mild steel strips

Coil inner diameter - 508 – 600 mm

Coil outer diameter – 1850 mm (max)

Coil width - 200 – 500 mm

Strip thickness - 0.3 – 2.0 mm

Coil weight - 9MT (max)

MATERIAL HANDLING EQUIPMENT

To produce only 1 tones of finished rolled metal, it is necessary to haul about 40 tones

of various materials. In the course of production materials are moved and

transferred by means of hoisting and conveying machines and mechanisms are an

integral part of the production.

The major material handling equipment used in this plant are:

HOOKS:

Hook is a multipurpose gripping appliance which is widely used as a working

member of hoisting mechanism ( load cranes) and as an end elements of slings and

other lifting devices.

OVERHEAD BRIDGE CRANES:

Overhead bridge cranes are the most widely spread type of cranes in ferrous

metallurgy. They are different in their purpose, load capacity and design. A

traveling electric crane comprises a crane bridge having a traveling mechanism, a

trolley with a hoisting mechanism and control cab. The cranes travel along the

workshop or work site over cranes tracks. Depending on the crane purpose the

hoisting mechanism is provided with various lifting attachments; hook, load

beams, tongs mechanical grips electromagnet or clamshell. As distinct from a

hook crane, the clamshell crane trolley carries alongside with a traveling

mechanism two similar mechanisms; one for lifting the clamshell and other for its

locking.

COIL CAR:

This is a special hydraulic operated material handling equipment used to transport

coil from one part of the plant to another. It is also used to carry the coil under the

rails of overhead traveling crane, where the approach of the crane is not possible.

The coil car is similar to a massive trolley having wheels at the lower end.

These wheels move on the rail which are installed a few feet below the shop floor.

These

coil cars can be move up or down using hydraulic pressure. The forward

movement of the coil car is assisted by a gear pinion arrangement.