akhil project hyperlinked
TRANSCRIPT
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Kalmehswar, Nagpur
A project report on
PROCESSING OF MATERIAL IN JSW ISPAT STEEL LIMITED
Submitted by:
AKHIL SINGH CHAUHAN
BACHELOR OF TECHNOLOGY
in
MECHANICAL ENGINEERING
from
VISVESVARAYA NATIONAL INSTITUTE OF TECHNOLOGY
NAGPUR
as
a Summer Trainee from May 613 to June 513
under Guidance of
Mr. Dhanesh Vijayan
(Jr. Manager, Mechanical)
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ACKNOWLEDGEMENT
I take this opportunity to express my sense of gratitude to all those who guided me
and helped me whenever the going seemed difficult and the road ahead was not
visible. I am highly thankful to Mr. Pradeep Pandey, (The Manager) JSW Mumbai
without whose support I would have never a part of this company. I am also thankful
to Mr. Satish Chauhan (The Manager, Electrical),JSW ISPAT, Nagpur for assigning
me to the projects which were truly enriching in nature and scope. I am obliged and
thankful to Mr. Sudhakar, HOD (CRM), JSW ISPAT, Nagpur who cleared my technical
queries.I am greatly indebted to Mr. Dhanesh Vijayan, (Jr. Manager, Mechanical),
JSW ISPAT, for acting as a guide for me in every aspect in the industry. I would like to
extend my gratitude to Mr. Varghese (Asst. Manager);Mr.Abdul Mallik(Asst.
Manager); Mr.Amit Chatterjee(Dy. Manager, Mechanical Maintenance);who were
with me through this entire journey. They inspired me to think beyond and to always
look for better solutions. I am deeply inspired by their profound thoughts, which
took me to light whenever the path became difficult. I also like to extend my thanks
to Ms. Shweta Bhalekar (Dy. HR-Manager) and to all the operators ,workers who
shared their experience with me to enhance my knowledge and staff of JSW, ISPAT ,
Nagpur who gave me great insight into the day to day operations of the plant.
And last but not the least I would like to thank God , my parents and my friends
without whose blessings and support ,I could have never be a part of this company.
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KALMESHWAR , NAGPUR
CERTIFICATE
This is to certify that Mr. Akhil Singh Chauhan student of Visvesvaraya
National Institute of Technology, Nagpur has successfully completed his
project entitled Processing of Materials in JSW ISPAT Steel ltd.
Kalmeshwar for the period of one month May 6 13 to June 5 13 in our
organization as a part of summer vocational training.
During this period we found him honest, sincere and hard working. We
wish him all the best in his future endeavors.
Mr. Dhanesh Vijayan
Training Guide
(Jr. Manager, Mechanical) HOD - HR
JSW ISPAT
Mr. Satish Chauhan kalmeshwar, Nagpur
External Guide(The Manager, Electrical Maintenance)
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1. INTRODUCTION
Engineering in general, and Mechanical engineering in particular, deals with a wide
spectrum of products, ranging from large and complex systems comprising ofnumerous elements down to a single component. Apart from being a physical object,
a product can also be a service that requires the application of engineering
knowledge, skills and devices to be useful to society.
In this project report entitled as Processing of materials in JSW ISPAT Steel,
Kalmeshwar the layout of the plant is explained as my observation. The plant is
basically a cold rolling plant where raw material is Hot rolled coil (HR-coil) which is
supplied from other plants of JSW located at dolvi and vasind-MUMBAI.
Various processing lines are explained in detail ,with their input material ,output
product. The process being done in the machine and the mechanisms involved are
also explained in the coming chapters of the project .
The problems coming in the normal working ,the mechanical maintenance work are
also taken into light as a part of this project report. The work of engineers
,operators, workers and their healthy coordination to give profitable outputs is also
seen and observed during the training period .
The various processing lines in the plant are:
Hot Rolled Slitting (HRS) Continuous Pickling Line (CPL) 6 HI Mill 4 HI Mill Skin Pass Mill Continuous Galvanizing Line (CGL) Color Coating Lines (CCL) Galvalume Line Cut to length (CTL)
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2. About JSW Group
Being 6th Biggest group in the world JSW Group is one of the fastest growing
business conglomerates with a strong presence in the core economic sector. This Sajjan
Jindal led enterprise has grown from a steel rolling mill in 1982 to a multi business
conglomerate of more than US $15 billion is a part of O.P. Jindal Group.JSW has set upbusiness facilities in various core sectors of India. With verticals that are exploring
innovative and sustainable avenues in steel, energy, infrastructure and cement, the
Group is paving the way for Indias development as a global superpower. JSW Grouphas diversified interests in Steel, Energy, Minerals and Mining.
Aluminum, Infrastructure and Logistic, Cement and Information Technology. JSW
Steel Limited is engaged primarily in manufacture of flat products viz. H R Coils, CR Coils,
Galvanized products, auto grade / white goods grade CRCA Steel and Power. JSW Steel
Limited has the largest galvanizing production capacity in the country and is the largest
exporter of galvanized products with presence in over 74 countries across five
continents. On its road to growth and expansion, the Group is also conscious about its
responsibility towards environment and social development. Eco-efficiency is a matter
of principle. Preventive measures for damage to the environment are taken into
account at the planning stage of production and growth. JSW Foundation, an integral
part of the Group, is the CSR wing, with a vision to create socio economic difference in
the fields of Education, Health and Sports, Community Relationship/Propagation as well
as Art, Culture and Heritage.
Group of Companies:
JSW Steel Limited
JSW Energy Limited
JSW Holdings Limited,
JSW Infrastructure and Logistics Limited,
Vijaynagar Minerals Pvt. Ltd
Jindal Praxair Oxygen Co. Ltd
JSoft Solutions Limited.
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3. About JSW Steel Ltd.
JSW Steel is Indias leading private sector steel producer and among the
worlds most illustrious steel companies. JSW Steel is around $9 billion global
conglomerate including JSW Ispat Steel spread over six locations in India and a
footprint that extends to the US, South America and Africa. The flagship company of
around $15 billion JSW Group, JSW Steel is testament to decades of experience and
a dynamic culture that have culminated in the company becoming the leading
provider of specialised steels in India. The steel plants in Karnataka, Tamil Nadu and
Maharashtra have a combined installed capacity of 14.3 million tonnes per annum
including JSW Ispat Steel where we have a majority stake. With the objective of
touching 40 million tonnes in the next decade, we are expanding capacities at our
existing sites and setting up plants in new locations. On the anvil, are two 10 million
tonne greenfield facilities in West Bengal and Jharkhand.
History
The JSW Groups foray into steel manufacturing began in 1982, when it set up
the Jindal Iron and Steel Company with its first steel plant at Vasind near Mumbai.
The next two decades saw significant expansion and several acquisitions, following
the merger of Jindal Iron and Steel Co (JISCO) and Jindal Vijayanagar Steel Ltd (JVSL)in 2005. Today there are JSW Steel and JSW Ispat Steel plants in six locations in India
Vijayanagar in Karnataka, Salem in Tamil Nadu, and Tarapur, Vasind, Kalmeshwar
and Dolvi in Maharashtra. In 2010, the company acquired a majority stake in Ispat
Industries.
The global operations of the company include a plate and pipe mill in the US. In
order to securitise resources, the company has acquired mining assets in Chile, USA
and Mozambique.
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4. About JSW ISPAT Steel, kalmeshwar
JSW Steel group had coalition with the company from 2011. Ispat is the integrated steel
plant in Maharashtra and is located at Kalmeshwar which is about 25 kms from Nagpur.As part of the JSW Steel group, the plant underwent a dramatic transformation and
started making profits from the first year onwards .The downstream steel products
manufacturing and servicing facility of JSW ISPAT Steel limited houses the state of the
art technology in the field of cold rolling, galvanising, colour coating , galvalume and
pipe and tube. Currently the complex is having capacity of producing 0.225 million
tonnes of Galvanised Plain/Galvanized Corrugated plant, 0.1 million tonne Galvalume
plant, 0.33 million tonne Cold Rolled Coils Plant, 60,000 tonne Colour Coated sheets
plant, 12,000 tonne Tube plant and 44,000 tonne Pipe plant. The capacity of the plantis dependent on the gauges of products produced. The capacity, as cited by the unit at
certain select gauges, is around 0.33 million tonnes per annum (MTPA). To reach its
corporate objective of 1 MTPA, the Kalmeshwar unit is undertaking various initiatives
for enhancement of production. With an employee strength of more than 750 regular
employees, Kalmeshwar based unit of JSW is crucial part of JSW steel empire. The unit
is one of the Quality-conscious units of this conglomerate.
Hot Rolled Steel, the primary input material for the JSW, Kalmeshwar unit comes to the
plant from Dolvi based unit of JSW. The first process to which the hot rolled iron is
subjected to is termed as Slitting. In this, the hot rolls are cut from both sides or from a
single side into sheets of desired width as per the customer orders. This step removes
the damaged edges of the rolls, thus improving the quality of the end product.
After slitting, the next step is Pickling of rolls. During transit and previous processing
underwent, surface of the rolls acquire some impurities and also gets oxidized, so they
are treated with chemicals (HCl acid) to remove these impurities. Next process in line is
Cold Rolling of sheets. After initial uncoiling and welding, the sheet is subjected to apair of rotating rolls to reduce thickness of pickled sheets, and achieve desired
mechanical and metallurgical properties for the sheets. A sensitive balance has to be
obtained in terms of the sheet thickness, width and length and involves a highprecision
work. The Galvanizing process takes place next and begins with the uncoiling and
welding of the coils to produce a continuous steel strip. This strip is then cleaned and
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degreased in a continuous cleaning section. The strip next enters the heat treatment
furnace. The zinc coating operation is performed by passing the strip in zinc pot.
Galvanized sheets are the major finished goods produced at this plant.
Color Coating is the next activity in the processing cycle of the sheets and provides a
variety of color coated sheets. This is totally market driven initiative and is earningrich dividends for the organization. A major application of these sheets is in
consumer goods industries. The organic coating can be done on the cold rolled steel
coils, galvanized coils, galvalume and various grades of aluminium .
Galvalume, a zinc-aluminum alloy coated steel sheet, is an upgraded product from
JSWs hot dip metal coating galvanizing line is the latest offering. JSW Steel Ltd is the
first Indian Company, under a technology licensing from BIEC International Inc., USA
to produce Galvalume sheets - the fastest-growing sheet steel product renowned forits excellent corrosion resistance and heat reflectivity. The Galvalume production has
started at Vasind unit and is at advanced stages of production at Kalmeshwar.
Customers of JSW ISPAT:
STEMCOR (UK) Ltd. UK JSW ISPAT ,DELHI SATYAM AUTO TRIMURTI ENGIMETAL & STEEL WORKS JSW ISPAT ,BANGLORE METEX METAL EXPANSION FACTORY RANA ENTERPRISES ,FARIDABAD YOGESH ENTERPRISES Ltd. ,NAGPUR BEEKEY STEEL INDUSTRIES Ltd., VISHAKHAPATANAM KAMADHENU STEELS, COIMBATORE AKANSHA SALES PROMOTERS ,BHOPAL GEORGE & COMPANY ,THRISSUR BUHARI HARDWARE, CHENNAI ARIHANT ENERPRISES ,GOA MANMOHAN ISPAT Pvt. Ltd. ,PUNE
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5. The Hot Rolled Slitting Line (HRS)
The basic work of line is to trim the sides of HR coils which is the raw material for the
plant. This is brought from the JSW plant at DOLVI. The line is manufactured for
processing of cold rolled coils but is now used for HR coils and hence the line is called
as HRS Line.
This is used to slit the length and trim the sides to obtain uniform width throughout
the coil so as to satisfy customers requirement in a best possible way. Also this is
used to trim the sides so as to make it suitable to be used in CPL lines as CPL lines
can be worked best on 1400mm width at max.
Processes in the Line:
It starts with uncoiler with weight limit:35 tonmax and 22 ton-min
Uncoiler is provided with segments to hold the sheet tightly which arehydraulically operated. The various IDs used are 508mm,610mm,710mm.
Then pinch rolls hydraulically operated to press and plane the sheet passing.
Then shear unit is there to cut the ends . After shear there are side guides to hold the sheet in its lateral position. Then slitter head is there where trimming of sheet is done as per customers
requirement and scrap is collected by scrap winder.
Then there is a loop table ,which acts as accumulator to make the processcontinuous, because the process stops for shear cut.
Then there is exit shear cut and coil is collected in recoiler and passed on to itscustomer /next process that is CPL lines.
Material grade is mild steel :ST46 IM
Input dimension : 5mm*1850mm max
Output dimensions : no thickness reduction and width as per customer.
CAPACITY:The installed capacity of this line is 96006 MTPA.
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6. Continuous Pickling Line (CPL)
The output of HRS line is the input material for CPL. The sheets supplied from HRS
line have layer of various oxides ,corrosion layer , dirt, scale etc which are to be
cleaned and removed before sending for processing in Mills.
In this line Pickling that is acidic treatment ,rinsing and drying is done to remove
those acid layers which are basic in nature.
Processes in the line:
It has a uncoiler at the starting of IDs 508mm,610mm, 710mm. There are twouncoilers one is at lower side and other at upper side called as UPPER PASS LINE.
This upper pass line is just to save time that is consumed in recharging the
uncoiler and helps to achieve the target on time. Snubber is used to support the coil to get passed further and this is operated
hydraulically.
Then there is Scale Breaker roll that just press the sheet and breaks the scalelayer at the surface. This is also controlled by hydraulics.
Then there is Rough Leveler segment which levels the sheet.o Then a Shear Welder Unit is installed in the line. This joins the
consecutive rolls to maintain continuity of the line.First the two sheets
are cut by pneumatic sheer then they are placed parallel to each other
for welding.
o The type of welding done is MAG welding. The material used as filler iscopper coated carbon rods, which are continuously supplied by using
sensors.
o There are two welding torches used for welding that are automaticcontrolled. For two torches there are two cylinders ofCO2 provided
o CO2 is used to cool the joint instantly. It is supplied at the pressure of 60bar. It is stored in green coloured cylinders carrying 32 kg of the gas.
This gives light blue color flames during welding.
o After this the joint is checked by the operator and if it is imperfect ,thenagain Metal Arc welding is done manually using filler rods.
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Then sheet is passed in a looper called as Wet Loop Pit. It act as a accumulatorto make process continuous and also water cleans the dirt and other water
soluble impurities present on sheet surface.
Then sheet is passed through assembly of Unfolding roll unit, Squeezer rolls,Briddle rolls which helps in planning the sheet and creating tension in it.
Then Pickling Tanks are there where pickling-i.e. acidic treatment is done. Acidused is conc. HCl of conc.15-16%. This helps the actual removal of oxide layers,
scale layers from the sheet. To pass the sheet special rolls called as wringer rolls
are used.
The there is Cascade Rinse unit where simple washing of sheet is done by usingwater to remove the treated acid. Then hot air dryers are used to dry the sheet.
Then again there are assemblies of bridle rolls , deflector rolls , pinch rolls and aloop car is installed to maintain the continuity of the line.
Then there is a side trimming unit to remove the excess edges and scrap iscollected by scrap winders.
The line also has CPC systems i.e. Centre Position Control. It is an automaticsystem that controls the lateral motion of sheet and align sheet axis properly.
Then at end there is EPC system that is Edge Position Control and finally arecoiler and exit coil skid ,from where coil is passed to mills or CGL or CCL as per
customers requirement.
Input : 1.2mm * 700mm min . (HRS product)
: 5mm * 1280mm max.
Output : pickled coil of dimensions same as input
Capacity : 3.56 Million Tonnes Per Annum.
Next process: CGL or GALVALUME or 6HI ,4HI or Skin Pass
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7. 6HI Reversible Cold Rolling Mill
This line is installed in the year 1988 in collaboration with HITACHI JAPAN. The
line perform the task of reducing thickness without increasing the width of sheet.
6six rolls and HI-horizontally integrated
This line has created a record of reducing thickness of the sheet to .09 mm.
The mechanism of this line is complete hydraulics and bit pneumatic.
About rolls:
The inner two rolls are called work rolls. These are in direct contact with thesheet and applies pressure to the sheet. Their minimum diameter is 405 mm and
maximum diameter is 440mm are made of cast iron. These needs to be changed
after 500tonnes of loading. These are directly driven by DC motors connected to
shaft by shear coupling. The shear couplings have shear bolts that breaks when
safe limits are exceeded and prevents breakdown of sheet and work rolls.
The two rolls next to work rolls are called as Intermediate Rolls (IMR). Theseconnect outer rolls and work rolls. They helps in applying load at the middle of
the sheet and provides same thickness reduction throughout the width. These
rolls can be moved longitudinally by hydraulic piston. These needed to be
changed after 1000 tonnes. Their diameter is 510mm. The two outermost rolls are called as Backup Rolls. These rolls are given
hydraulic pressure at their edges. In 6HI mill load is applied at the bottom most
back up roll. Their diameter is more than 1350mm. These are changed after
15000 tonnes.
All these rolls are made up offorged alloy steel.Input : 1.8mm * 500 mm min.
4mm * 1250 mm max.
Coil : ID- 508 mm OD- 1850 mm and max weight 20 tonnes.
Output : 0.12 to 0.5 mm thick sheets.
Capacity : 2,30,856 MTPA
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Parts of mill:
Pay off reel Three roll feeder Entry tension reel (ETR) Entry tension bridle roll Hydraulic system Delivery tension bridle roll Oil lift system Hot water system Updraft fan blower Pump exhaust blower Roll changing car Air dryer unit Project block Entry gamma ray Delivery gamma ray
About Hydraulics:
The complete hydraulic system of the mill is divided into following systems:
1. Main hydraulic 2. Auxiliary hydraulic system 3. Roll coolant system
4. Gear lubrication system 5. Bearing lubrication system 6. Mist lubrication
Main Hydraulic System:This system is responsible for pressure application at
backup roll, shifting of intermediate rolls, and bending cylinders. The oil hlp-46,
pump- axial piston pump. The maximum pressure applied is 210 kg/sqcm. The tank
capacity is 3000 ltrs. This is also called as High Pressure System.
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Auxiliary System:The oil used in this system is hlp-46, pump-Vane pump. The
maximum pressure maintained is 75 kg/sqcm. maximum temp 54 degree C. This is
also called as Low Pressure System.
Gear Lubrication System: This system maintains the lubrication between the
gears. The oil used is sp-320, pump- gear pumps. The temperature is maintained
between 40-50 degree. The tank capacity is 6000 ltrs.
Roll Coolant System: This system is used to cool the rolls as they gets heated up
due to friction and high operating speeds. This uses emulsion of 3%oil and 97%
water ,by the help ofcentrifugal pumps.
Bearing Lubrication System: The shafts are mounted on bearings for easy
rotation. So bearings are checked for lubrication . The oil used is servo prime 46/57by gear pumps. The working pressure maintained is 2kg/sqcm.
Other Systems:
Accumulator : This provides excess oil to increase the pressure whenrequired. This is automatically controlled.
Magnetic Separator: The emulsion that is returning after cooling and otheroils used in operation brings with them sheet particles as impurities. This
magnetic separator removes those impurities .
Valves: The hydraulic system is incomplete without valves. The valves usedin the machine are direction control valve ,force valve, pressure reducing
valve, flow control valve. In 6 HI mill force motor valve is used.
Valve stand: A stand on which all the automatic valves are mounted. Fume Duct: This helps forcing the fumes out of the mill. Heat exchangers: The oil that is used in the various systems of the mill gets
heated up when it returns back to the tank and this hot oil cannot be used ,so this is cooled using heat exchangers. Tube type and fin type heat
exchangers are used where water is used as coolant.
Next Process: CGL or Galvalume or CCL or CTL.
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8. 4 HI Reversible Cold Rolling Mill
This machine is manufacture by DEMAC . It comprises of 4 rolls horizontally
integrated. It also does same job as 6hi mill i.e. reducing the thickness ,but working
pressure , valves , load application differs from that of 6 HI mill.
In this the load is applied from top backup roll with help of hydraulic jack.
About Rolls:
There are 4 rolls, the outer two rolls are called as backup rolls and inner ones are
called as work rolls. The work roll diameter ranges from 388to 434 mm. The work
rolls are changed after every 700 tonnes and Backup rolls after 10000 tonnes.
The Lubrication of backup roll bearing uses morgoil( ss680) and work roll bearing
lubrication is mist lubrication. The loading is done on top backup roll. The machine is
work roll drive. The work rolls are connected to the motor shaft by spindles and
shear couplings.
Input : 0.4 mm * 700 mm min.
4.5 mm * 1220 mm max.
Coil : ID -508mm OD- 1850 mm
Maximum loading about 20000 tonnes
Material hot rolled pickled low carbon steel.
Capacity : 43502 MTPA
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Parts of 4HI mill:
Pay off uncoiler
Three roll feeder (leveler) ETR Entry coil car Entry deflector roll Roll force cylinder Main drive system DTR Auxiliary hydraulic system Morgoil lubrication Motor lubrication Gear lubrication Roll coolant system Cooling tower fan Updraft fan blower Fume exhaust system
Air dryer unit
Main Hydraulic System: This system is responsible for loading the backup
roll. This is also known as High Pressure System.This system is used to apply
load at the back up roll. The oil used is SS46 at a pressure of 160 kg/sq.cm.
Maximum temperature is 45 degree C.
Auxiliary Hydraulic System: This is also known as low pressure system as
working pressure is 60 kg/sq.cm. The oil used is SS320. The pump used here is vane
pump.
Gear Lubrication System: this system takes care of lubrication in gears. The oil used
here is OMILA 460, at a pressure of 3.8 kg/sq.cm. Maximum temperature in this
system is 48 degree C.
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Other Systems in the Unit:
Valves: Various valves in the unit are moog valve,check valve, shut off valve,pressure release valve, gate valves, direction control ,flow control.
Moog valve: This valve maintains equilibrium of pressure on either sides ofthe roll.
Centrifuge Unit: This is a filtering unit basically. This uses a centrifugal pumpto remove water from oil returning from rolls.
Magnetic Separator: this removes magnetic impurities like metallic particlefrom oil returning from the rolls.
Heat Exchangers: the oil returning from the rolls gets heated up due to highworking speeds and hence needed to be cooled. For this tube type or plate
type heat exchangers are used with water as a coolant.
Next Process: CGL or Galvalume or CCL or CTL as per customer.
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9. 4 HI Skin Pass Mill
In this process, the cold rolled annealed strips are given the desired surface finish.
This improves the flatness and suppresses the yield point elongation. Anti-rust oil is
used on the strip surface as protection from rust. This also makes the sheet suitable
for colour coating.
As the name says this also has 4 rolls as 4HI mill. The inner rolls are called as work
rolls and the outer as back up roll. Diameter of work roll is 425mm to 480 mm and
width as 1400mm max. The back up roll diameter is 1160mm to 1280mm width
1400mm. The material i.e. is input in this unit is galvanized annealed low carbon
cold rolled strip , pickled low carbon.
About Coil: ID- 508mm to 610 mm.
OD- 900mm to 1960 mm.
Max. weight 23 tonnes.
In this line the sheet is just passed , and first bending rolls at pressure of 150kg/sqcm
is used to bend the sheet and main jack is applied a pressure of 200 kg/sqcm torough the sheet.
The rolls are driven at maximum speed of 1000 rpm and tension of maximum 17
tonnes is applied.
Capacity: 82,319 MTPA.
Next Process: CCL or CTL
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oxidizing zone is the charging zone ,in which propane and air is inserted which
gives burning. This zone has RTF i.e. Radium Tube Furnace. Then there is
soaking zone which is to maintain sheet in the required temperature for
some time for constant heating of the sheet. Then there is cooling zone in
which sheet is cooled in the furnace and not in air to maintain rate of cooling
and avoid any martensite formation. This zone also has heat exchangers. This
whole furnace is maintained in an inert atmosphere of 71 % N2 and 29% H2.
After this the annealed sheet is passed through a pot ofzinc bath. Where zincis maintained at temperature of 440-460 degree C. The zinc is melted by
induction furnace , provided with air nozzles that inserts air at 0.34 bar
pressure. This air helps to control sheet thickness as well as surface finish of
the coating. The thickness of the coating also depends on the speed with
which the sheets are passed through the bath. Now the sheet is passed through air driers and water is showered to cool the
sheets. This helps cooling the sheet as well as maintaining coating thickness.
The thickness is measured in Gram per meter square. And its thickness is in
microns according to international standards. In the zinc pot there are special
bridle rolls made of AMCO STEEL, they are resistant to melted zinc
atmosphere.
After this there is a 4 HI Skin Pass Mill, that is optional and is used only forcustomers requirement or when sheet is required to be colour coated.
Then there is an assembly of tension leveler rolls which plans the sheet. Andthen there is chromate tank. This tank applies a chromate layer on the
galvanized sheet. The zinc coating also has pores so to fill them and also to get
sheet lusture, this coating is applied.
Then there is a logo unit, where logo of JSW is being inked on the sheets. Then there is exit accumulator, exit sheer and a recoiler.
The unit is also installed with 5 CPC units and EPC unit at the exit. The machine
is completely hydraulic as well as pneumatically controlled.
Next Process:
CCL or CTL or Customer directly.
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11.The Galvalume LineGALVALUME , coating of sheets with a mixture of ZINC and ALUMINIUM.
GALVALUMEs revolutionary coating formula was developed by Bethlehem Steel
Corporation, in the year 1972. The GALVALUME steel coating combines the barrier
corrosion protection of aluminium with the sacrificial protection of zinc, giving the
advantages of both metals. The result is a coating that lasts a long time, a coating
that provides cut-edge protection along sheared edges, and therefore, a coating that
offers excellent protection to steel sheet.
Input : (0.2 mm to 1 mm)* 1250 mm
Output : zinc and aluminium coated sheets.
Process in the line:
After entry of sheet there is a joining unit which joins two consecutive sheets. Then there is cleaning unit , which is just like washing of clothes. This has alkaline
tank in which sodium bicarbonate is used to treat the sheet. Then there is
electrolytic cleaning tank to remove ionic impurities.
Then sheet is passed through a furnace having there are 3 zones each having 8burners and a temperature of 1200 degree C is maintained in these zones. The
burning is done by a mixture of LPG , propane and air .
Then there is RTF- radium tube furnace in which electric heating is done and atemperature of 750 degree C is maintained. Then there is a vertical soaking zone.
Then there are jet cooler and then zinc aluminium pot, in which 40-45 % of zincwith 52-57 % aluminium and rest silicon is added and a temperature of 600
degree C is maintained in the bath. Provided with air nozzles to maintain coating
thickness. The coating thickness is measured by X-rays.
Then there is air dryers and water quench followed by Skin Pass Mill if required.Then a tension leveler rolls and acrylic coating is done followed by chromate
coating. These coatings are done to fill pores remained in zinc aluminium pot
and acts as corrosion resistant and lusture provider.
Next Process: CTL , CCL or Customer
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12.Galvalume v/s Galvanized Products Galvanized sheets are zinc coated whereas Galvalume is coating with zinc ,
aluminium and silicon.
Galvalume has excellent life performances in bare exposures then galvanizedsteel. If painted sheets are to be used than galvanized sheets are also good.
Galvalume is better than galvanized sheets to be used in coastal areas. The lusture of galvalume is much more long lasting than galvanized. The galvalume prevents edge creep better then galvanized sheets. But
galvanized sheets are better resistant to scratches and end cuts. Galvanized
may take a longer to show edge rust, however once the rust begins , it could
corrode the entire panel. The smoothness of galvanized sheets are better than galvalume. Galvalume products are projected to outlast galvanized products (with an
equivalent coating thickness) in various atmospheres by up to 9 times as per
data of ZAC association.
Galvanized products show paint peeling effect whereas paint peelings are notshown in galvalume product.
Galvalume due to presence of aluminium are more heat resistant thangalvanized products.
Bare galvalume and painted galvalume sheets suffer rapid corrosion when incontact with mortar and concrete. Bare galvanized and painted galvanized
perform better in this type of environment.
On economic grounds galvanized products are cheaper then galvalume. Painted galvanized sheets are better than painted galvalume because paint
adhesion of galvanized sheets are much better then galvalume sheets.
Galvanized coating doesnt breaks due to bending as galvalume breaks , sogalvanized sheets should be used in products where lot of bends are , and
galvalume to be used for straight roof products with less or no bends.
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13.Continuous Color Coating LineIn this line the sheets supplied from CGL and GALVALUME lines are coated with color
coatings. This line is first of its kind in India and was installed in the year 1988. The
line performs coating of many different kind of colours as:
Burgundy red Brick red Pepsi blue Environment green Nut brown Off white Mist green Light grey
These sheets founds a large application in automobile sector, wall panels,
shells etc. This product is durable, cost effective and easy to use.
Processes in the line:
The sheet surface is cleaned chemically and its surface is prepared for coating. Then sheet is service coated. In this the paint is applied by a paint coating
machine. Then the sheets are heated in ovens to relieve stresses. The baking temperature
depends on line speed and thickness of the coil. Then the sheet is cooled.
Then a primer coating is done ,which is same for all knd of color coatings andhelps the paint coating to remain on the surface.
Then top coating/printing are carried by paint coating machine, for which epoxy,polyester paints are used. Then drier is provided to dry the surface and attain
temperatures b/w 100-120 degree C. If required pro-gold treatments are applied
for better paint adhesion, with corrosion resistant. Finally, guard film( sticking polythene) is applied to safeguard against scratches
and other surface defects.
Input : 0.2mm to 1.2 mm *1350 mm wide galvanized/galvalume sheets.
Capacity : 60000 tonnes per annum.
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14. Cut to length (CTL)
This line can be considered as last line of CRM Finishing Lines. In this line the sheets
are cut into length required by the customer. The machine is manufactured by
Godrej and is fully automatically controlled. It gets its input from 6HI ,4 HI
,CGL,CCL,GALVALUM lines. There are total 4 CTL lines in operation.
Input : 0.3mm * 300mm to 3mm * 1250mm
Output : sheets of length 700mm to 4000mm as per customer requirement,
without any change in thickness.
Capacity: 83298 MTPA
Process in the line:
There is an uncoiler at the entry and a snubber hydraulically operated to properlypass the sheet further.
Then there are straightening rolls to level the sheet. Then there is a loop table to maintain continuity of the line ,this is provided with
sensors at the bottom of the loop to work automatically. There are side guides fixed at the sides to check lateral movement of sheet. Then there is feed roller and measuring roller unit ,which measures the length of
the sheet which is to be sheared off.
Then there is shear unit which is actuated by eccentric shaft with a pneumaticallycontrolled clutch.
Then again there smooth levelers rolls,to further plane the sheet. Then at the exit there are magnetic rolls to plane the sheet and then there is exit.
Also there is FLR-filter regulator lubricator unit to filter the air supplied for pneumatic
operations. This is maintained at 4.4 bar. Hydraullic Vane pumps are used to supply oil
and tube type heat exchangers are installed to cool the oil supplied.
Next Process:Customer
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15.About Mechanical MaintenanceThe most important department of any industry looking after the proper functioning
of machines ,because if machines suffers any break down or failure , its results areseemed in the production rate ultimately.
The team of mechanical maintenance needs to check each of the machines, their
parts, gears , bearings, tools , load,etc on time basis for the proper running of the
plant. The mechanical maintenance is categorized into five categories as:
Break Down Maintenance : it is the maintenance work performed after thereis a break down of the machine or its parts. This kind of maintenance work
takes time and it leads to decrease in production rate.
Preventive Maintenance : this type of maintenance is to check parts after aperiod and do the actions required to prevent any breakdown.
Predictive Maintenance : this is to predict the failure or any faults before theyoccur by previous data of maintenance available.
Proactive Maintenance: this seems to be similar to above maintenance work,but is a bit different and requires analysis of parts of machines and is just like
estimating the future of machine parts by studying its present conditions. This
is the best type of maintenance work as by this we know before hand that
what can be the problems that can occur in future.
Shut Down Maintenance: the maintenance work performed ,when there isscheduled shut down of machine is there. At this time each of the parts of the
machine are checked for lubrication, cracks etc.
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16. Summary
This report is a presentation of the findings of the project work carried outduring the summer training at JSW ISPAT STEEL Ltd. Kalmeshwar during
one month period from May 613 to June 513. The project is entitled as
Processing of raw materials in JSW ISPAT Steel Ltd. In this project overall
study and observation of each lines were done i.e. the line at which raw
material is first brought and from which it comes out as a finished product
to the dispatch section. This project was to understand the basic
mechanisms and processed involved in the lines.The main product of the company are cold rolled galvanized, galvalume ,
color coated and cut to length sheets. The raw material is Hot Rolled coil
obtained from Dolvi unit of JSW. In this project all these lines were
explained , their inputs , outputs, and line capacities were mentioned. The
hydraulics behind the functioning of 6HI and 4 HI are discussed. The
difference between galvanized and galvalume products are also
mentioned, the work done in the department of Mechanical Maintenance
is being mentioned in brief.
At social level , the relationship between engineers, workers and
operators were seen and their coordination to get finalized product and
achieve target on time is seen.