2.  Overview
 CRC-overview
 Plant visit
oObservations
 Operations
 Maintenance
 Electrical Systems
 Learning
 Suggestion & conclusion

3. The Beginning
The modern iron and steel industry in India owes its origin to the grand vision and
perseveranceof Jamsetji NusserwanjiTata. The Tata Iron and Steel Company
Limited (Tata Steel) was registered in Bombay on 26th August1907. The
construction of the steel plant was then taken up in earnestwith the firststake
being driven in February 1908. R.G. Wells, an American with steel plant
construction experience took over as the General Manager in 1909. Success came
when the firstblast furnacewas blown-in on 2nd December 1911, and thefirst
ingot rolledon 16thFebruary 1912.
The cost of the plant as erected came to around Rs.23 million.
Tata’s supplied 1500 miles of rails and 300,000tons of steel to the allies’ war
effort. During this period, Tata steel embarked on an expansion of the works.
At that time of 1939, Tata Steel came to be regarded as the largestSteel plant in
the British Empire and also the cheapestexporter of pig iron in the world (the
latter reminiscent of the state in 1999).

4. Periodbetween1960-80
During the decade of the sixties, consideration was given to the expansion of Tata
Steel in the private sector. In July 1961, Tata Steel obtained an industriallicense
for setting up alloy steel
Sinter plant: A new 1.37 mtpa sinter plant (SP2) to raise the total sinter
production to 2.5 mtpa and thereby, increasesinter in blast furnaces to around
65%.
Waste recovery: 1 Mtpa Waste recycling plant to recover metallics fromthe plant
was established
Ancillary technologies: Thelimited reserves of coking coal in India havealways
spurred Indian iron makers to strivefor lower cokerates. Tata Steel
commissioned a coal injection unit in 1991 for its F blast furnace. The system
developed by Kloeckner SstahlTechnik (KST) was adopted.
Keeping in view the international and domestic Steel scenario, it was felt
necessary for Tata Steel to set up an internationally competitive flat products
complex.

5. New Cold Rolling Mill at Tata Steel
In addition to modernization, Tata Steel has defined its vision for the next
millennium and has embarked on an unprecedented expansion in flat products.
As a firststep, taking into accountthe doubling of the capacity of the HSM, a 1.2
million tonnes cold rolling complex has been commissioned in Jamshedpur
towards the middle of the year 2000. Someof the salient features of this new
development are highlighted.
Facilities inthe coldrolling complex
Internationally, the technology of cold rolling has developed to an extremely
sophisticated level. This progress has been augmented by the work on technology
by equipment suppliers around the world, focused on further improving the
processes to producebetter products, thereby propelling cold rolled strips to
higher levels of quality and cost competitiveness.
The major facilities include a pickling-cum-tandemcold rolling mill, an annealing
facility, and galvanizing lines.

6. Steelmaking andcasting:
Major developments inthe steelmaking andcasting area includes the following:
 Switchover fromduplex and open hearth steelmaking to the oxygen
process.
 Adopting optimum KD vesselconfiguration (to accommodate the high slag
volume as a result of high silicon and phosphorus in hotmetal) and use of
bottom inert gas agitation.
 Strategy to make low phosphorus Steel.
 Improvementof vessellining life from160-180 heats to over
1000 heats
 Adoption of continuous casting through billet and slab casters.
Tata Steel Today
As a resultof innovations and technological up gradation, Tata Steel, has become
a well-run ultra-modern plant - one of the best in the world. Fundamental
changes in some metallurgical parameters havebrought aboutthis remarkable
transformation. Necessity became the mother of invention and numerous
innovations invoked improvement.
In terms of hot metal costs, Tata Steel is amongstthe lowestin the world and has
a clear advantage over other major integrated producers. The costof conversion
fromhot metal to a finished productsuch as hot rolled coils where Tata Steel has
not been very competitive so far would be taken care of in the near future as
investments already made to achieve the results foreseen. High ash in coke, poor
roomtemperature and high temperature strengths of coke, high alumina in the
iron oxide feed, high silicon in hot metal, low yields during steelmaking, low yield
of finished products, high energy consumption, high manpower, etc. have been
the weaknesses notonly of Tata Steel but of the Indian Steel industry as a whole.

7. Appropriatesteps taken by the Company have already resulted in better yield
lower energy consumption, lower silicon in hot metal, lower silicon in hot metal,
lower lime consumption in steelmaking, higher vessellife, etc., all of which augur
well for the Steel Company in future.
Tata Steel inthe NewMillennium
Tata Steel is all set to establish itself as the supplier of choice by delighting all its
customers with its products and services. The Organization is envisaged to
become the mostcost competitive Steel plant to servethe community and the
nation. Where Tata Steel would venture, others will follow. The 21stcentury will
certainly see a new Tata Steel - an integrated Steel plant in India with truly world
class facilities along with a will to win amongsta committed and streamlined
workforce.

8. Cold rolling:
Cold rolling occurs with the metal below its recrystallization temperature (usually
at room temperature), which increases the strength via strain hardening up to
20%. Italso improves the surfacefinish and holds tighter tolerances. Commonly
cold-rolled products include sheets, strips, bars, and rods; theseproducts are
usually smaller than the sameproducts that are hot rolled. Because of the smaller
sizeof the workpieces and their greater strength, as compared to hot rolled stock,
four-high or cluster mills are used. Cold rolling cannot reduce the thickness of a
workpieceas much as hot rolling in a single pass.
Cold-rolled sheets and strips come in various conditions: full-hard, half-hard,
quarter-hard, and skin-rolled. Full-hard rolling reduces the thickness by 50%,
while the others involve less of a reduction.
Itis used to producea smooth surface, a uniformthickness, and reduce the yield
point phenomenon. It locks dislocations at the surfaceand thereby reduces the
possibility of formation of Lüders bands.

9. To avoid the formation of Lüders bands it is necessary to create substantial
density of unpinned dislocations in ferrite matrix. It is also used to breakup the
spangles in galvanized steel. Skin-rolled stock is usually used in subsequentcold-
working processes wheregood ductility is required.
Other shapes can be cold-rolled if the cross-section is relatively uniformand the
transversedimension is relatively small. Cold rolling shapes requires a series of
shaping operations, usually along the lines of sizing, breakdown, roughing, semi-
roughing, semi-finishing, and finishing.
If processed by a blacksmith, the smoother, more consistent, and lower levels of
carbon encapsulated in the steel makes it easier to process, butat the cost of
being more expensive.
Uses:
Typical uses for cold rolled steel include metal furniture, desks, filing cabinets,
shelves, tables, chairs, motorcycleexhaust pipes, computer cabinet and
hardware, all home appliances and components, shelving, lighting fixtures,
hinges, tubing, steel drums, lawn mowers, electronic cabinetry, lighting fixtures,
water heaters, metal containers, and a variety of construction related products.

10. On visiting the Tata steel Cold rolling complex plant located in Boisar, one gets to
learn a lot about the various operations, maintenance work as well as the
electrical systems that are used for manufacturing the steel coils.
Following are the observations of the plant visit:
The manufacturing process of cold rolled steel coils requires a series of systematic
process and steps.
The hot rolled coils are obtained for processing fromthe Jamshedpur plant, these
hot rolled coils are stored in the pickling area for further processing, itis here
wherethe basic cleaning process of these coils takes place.
Fromthe pickling department these coils are further treated in the CRC plant, the
coils after the pickling process aregiven for adjusting their thickness to the 4-HI
mill, after which they are forwarded for the smoothening of their surfaceto the
annealing department.
Fromthe annealing department these coils are treated through the shot blasting
technique, required for giving them a mat finish.
By the end of all these processes, thecoils are further treated as per the client
requirement and specifications.
The Electrical maintenance department (EMD) handles the task of maintaining all
the electrical equipment and systems.
The maintenance process for any particular day is decided in an early morning
meeting lasting for 30-45 minutes, wherein all the pending work is accounted for
and work for each individual group is decided and distributed accordingly.

11. The regular methodology for maintenance includes cutting off the power supply
to the concerned system, opening the systemcomponents, cleaning the
components, and restarting the system.
Faulty instruments arereplaced and corrective measures aretaken to avoid the
errors fromreoccurring in future.
Maintaining every instrumentperiodically increases their life and ensures their
continuous efficiency.
The Tata steel CRC-(W) plant uses lots of complex electrical systems for its
functioning, these electrical systemoperateon high power voltages and are
seldom closed because of their important roles in the manufacturing of cold
rolled coils.
The CRC plant receives a total of 11,000 volts of power for its functioning; this
power is supplied to the high tension room (HT- room)
Fromthe HT-roomthis power is distributed to various transformers and electrical
systems, theplant uses a total of 8 transformers for its functioning.
Very complex electrical systems thatare used include the blastfurnace that is
used for the annealing process wherein a controlled flow of hydrogen gas is
maintained.
Also, the 4HI mill operates at relatively higher temperature and requires more
power.
Similarly, a detailed cleaning of the hot rolled coils takes place at the pickling
chain wherein hydrochloric acid is used to clean the sheets.
A blower is also used to obtain a specific required pressurefor the pickling
process, thesheets are then oiled and rinsed off by the usageof 4 rinsing tanks
that use water in between 30-50 degreeCelsius and distilled water that is used in
a slightly higher temperature of about 70 degree Celsius.

12. On visiting the plant one gets to learn a lot about the safety measures that are
required to be taken for ensuring a hazard freeworking environment.
The lock and key protection systemthat includes cutting off the power supply to
the machinery undergoing maintenance is very effective and fail proof way of
ensuring safety.
This systemis followed thoroughly by everyonein the Tata steel CRC plant, and is
a required mustfor everyone.
Further, one gets to learn the various electrical systems used like the 4Himill, the
shotblasting technique, the annealing technique and the pickling process.
The 4Hi mill
The pickling department

13. Tata steel CRC plant leaves no effort in ensuring the safety of its workers, butI
would like to put forward following suggestions for improved safety and better
functioning:
 Better exhaust systemto drain all the gases out of the shop floor.
 Avoiding any residualwater on the floor as it may lead to slipping and
tripping while walking.
 Better ventilation systemin the cellar becauseof its closed and confined
space.
The Tata steel CRC plant is a self-sustaining state of the art manufacturing plant
that looks forward to optimize its performanceevery passing day.
Itis also a great place to witness the incredible advances in the manufacturing
process of cold rolled sheets.
I personally thank all my mentors for giving me their tireless guidance throughout
the span of this internship.