This a report of my industrial trianing at salem steel plant(unit of SAIL) during winter 2017.

1. STEEL AUTHORITY OF INDIA Ltd.
SALEM STEEL PLANT, SALEM, TAMIL NADU - 636013
INDUSTRIAL TRAINING REPORT
DEPARTMENT OF MECHANICAL ENGINEERING
NATIONAL INSTITUTE OF TECHNOLOGY,
SURATHKAL, MANGALORE, KARNATAKA - 575025
By-
RAGHUNATH.V
Roll. No.- 16ME155
Reg. No.- 166139
Period of visit - 04.12.2017 to 15.12.2017

2. i
ABSTRACT
In order to study the process that takes place inside the steel plant industry, I
selected to do industrial training in SALEM STEEL PLANT , And I have
successfully completed my industrial training on HRM(Hot Rolling Mill) ,
CRM(Cold Rolling Mill), and process taking place inside those mills . The
process that I have understood have been submitted as the report. Hereby,I thank
the HRDC(Human Resource Development Centre) of SSP who gave this
opportunity.

3. TABLE OF CONTENTS
S.No. Title Pg No.
ABSTRACT i
1. INTRODUCTION 1
1.1. PRODUCT MIX 1
1.2. FACILITIES AND
CAPACITY
2
2. FUNCTIONS OF THE COMPANY 4
2.1.PRODUCTION DEPARTMENT 4
2.1.1. HRM: Hot Rolling Mill 4
2.1.2. CRM: Cold Rolling Mill 9
3. CONCLUSION 13

4. 1
1. INTRODUCTION
Salem Steel Plant, a special steels unit of Steel Authority of India Ltd, pioneered
the supply of wider width stainless steel sheets / coils in India. The plant can
produce austenitic, ferritic, martensitic & low-nickel stainless steel in the form
of coils & sheets with an installed capacity of 70,000 tonnes / year in Cold
Rolling Mill & 3,64,000 tonnes / year in Hot Rolling Mill. Its steel melting shop
can produce 1,80,000 tonnes of slabs per annum.In addition, the plant has
country's first top-of-the-line stainless steel blanking facility with a capacity of
3,600 tonnes / year of coin blanks & utility blanks / circles.
The steel melting facilities comprise ultra-high power Electric Arc Furnace,
Argon Oxygen Decarburising (AOD) Refining Unit with Level-II automation,
Ladle Furnace & Continuous Casting machine with state-of-the-art technology
to produce premium quality stainless steel slabs. The plant is facilitated with Hot
Rolling Mill which can roll both stainless & carbon steels & the mill caters
mainly to the input needs of stainless steel coils for the cold rolling mills.
Special grades of carbon steels other than structural steels are also rolled from
the facility includes weathering steels, high strength low alloy steels, etc., which
are extensively used in industrial sectors.
1.1. PRODUCT MIX
PRODUCT MIX TONNES/ANNUM
Cold rolled stainless steel flat product
(Coils/Sheets/Blanks) 66,600
Hot rolled stainless steel/No 1/ carbon
steel flat product (Coils/Sheets) 2,72,000
Total Saleable steel 3,39,200

5. 2
1.2. FACILITIES AND CAPACITY
AREA MAJOR FACILITIES PRODUCTS
CAPACITY/ANN
UM
(IN TONNES)
Steel
Melting
Shop
 Electric Arc Furnace
 AOD Refining Unit
 Ladle Furnace
 Continuous Caster
 Slab Grinder
Slabs 1,80,000
Hot
Rolling
Mill
 WalkingBeam
Re-heating Furance
 Roughing Mill
 Steckel Mill
 Down Coiler
 Roll Shop
Hot rolled Stainless
Steel/ Carbon Steel
Coils
3,64,000
Cold
Rolling
Mill
 Coil Build up Line
 Coil Preparation Line
 Bell Annealing
Furnaces – 2
nos.(with 8 bases)
 Annealing & Pickling
Lines – 3nos.
 20-High Sendzimir
Cold Rolling Mills –
3 nos.
 Strip Grinding Line
Cold Rolled Stainless
Steel Coils / Sheets
Hot Rolled Annealed
and Pickled Stainless
Steel Coils / Sheets
66,600

6. 3
 Skin Pass Mill
 Rotary Polisher
 Shearing Line
 Slitting Line
 Roll Shop
Blanking
Line
 Blanking Press
 Rimming Machine
 Annealing Furnace
 Pickling and
Polishing Machines
 Counting Machines
Cold Rolled Stainless
Steel Coin Blanks
/Utility blanks
3600

7. 4
2. FUNCTIONS OF THE COMPANY
2.1. PRODUCTION DEPARTMENT
There are two major units in Salem Steel Plant (SSP)
a) HRM
b) CRM
2.1.1. HRM: Hot Rolling Mill
Hot Rolling Mill complex is equipped with walking beam reheating furnace,
primary descaler, 4-hi reversing roughing mill, 4-high reversing Steckel Mill,
down coiler, laminar cooling & roll grinding machines, procured from world
renowned suppliers. The Steckel Mill, the mother unit of hot rolling with level-2
automation is provided with hydraulic gauge setting & automatic gauge control.
The continuously variable crown (CVC) controls the profile & flatness by roll
shifting & work roll bending system provide additional fine control of flatness
of the strip
Input
a) Carbon Steel slabs from sister steel plants viz Bhilai Steel Plant and Bokaro
Steel Limited.
b) Stainless Steel Slabs from Alloy Steel Plant, Durapur and from imported
sources.
c) Steel Slabs from the Steel Meting Shop(SMS).
Output
a) Hot Rolled Carbon Steel and Stainless Steel Coils and Plates.
Product Mix
With the commissioning of Hot Rolling Steckel Mill, Salem Steel Plant has also
entered the market of carbon steels. The Hot Rolling Steckel Mill is capable of
producing both stainless as well as non-stainless steels. In case of carbon steels,
the minimum thickness which can be achieved is 1.6 mm and in the case of
stainless steel the minimum thickness achieved would be 2.0 mm. The mill has
the capacity to roll up to 1300 mm width.

8. 5
Process
Slabs of carbon steel (or) stainless steel are received through wagons from Alloy
Steels Plant, Durgapur or Bhilai Steel Plant or from abroad and stored in slab
storage yard. As per the schedule the slabs are charged into the Walikng Beam
Reheating Furnace and annealed to a suitable temperature. Later these slabs are
discharged from furnace and sent to Roughing Mill. In Roughing Mill the slabs
are rolled to transfer bar to a thickness of 25 mm and sent to the Steckel Mill for
further reduction. Having achieved required thickness, the material is cooled
with the system of Laminar Cooling in case of carbon steel and coiled in Down
Coiler. In case of stainless steel the material is directly coiled in Down Coiler
after natural cooling. From Down Coiler HR Coils are taken to CRM or
customers through trucks.
PROCESS FLOW: HOT ROLLING MILL
1. Walking Beam Reheating furnace
2. Descaler
3. Edger
4. Roughing mill
5. Crop shear
6. Coiler furnace
7. Steckel mill
8. Laminar cooling
9. Pinch roll
10. Down coiler

9. 6
HOT ROLLING MILL FLOWCHART

10. 7
Functions of each unit HRM
Slab Yard
Slab yard is to store the slabs in a specific order. The slabs that are received
either by rail or by road are unloaded in this yard.
Goliath Crane
It is used to transfer the slabs from one placed to other within the range of crane
movement area.
Walking Beam Re-heating Furnace
This is a special structure constructed with firebricks to reduce heat loss.
Heating is done using LPG. The temperature maintained inside the furnace
depends on the type of steel in furnace. This furnace contains a walking beam to
move slabs from one position to other. The main advantage of walking beam
furnace is that the hot slabs are moved by one phase length without any damage
(i.e., the beam will lift the entire mass of ten slabs – placed apart by a definite
distance side by side – and moves one step forward and lowers them on the
furnace floor and retracts back to its position.This furnace can contain ten slabs
at a time.
Descaler
When the hot slab is discharged from the furnace, some elements in the slab will
react with the oxygen in the atmosphere and forms a compound called Scales on
the surface of the slabs. These scales are unwanted elements and to be removed
from the surface of the slab. The hot slabs with these scales are passed through a
descaler, which will break the scales. The scales so broken are wiped off the
slabs with high-pressure water jets. Scale free slabs will come out of the descaler
and will be forwarded to the roughing mill. Roller table enables movement of
these slabs without damaging the surface
Roughing Mill
This is a reversible mill. The slab thickness, which enters the mill, will be of the
order of 200mm. This will be reduced down to 25-30mm depending on the final

11. 8
thickness to be rolled in Steckle Mill. This thickness reduction from 200mm to
25-30mm takes place in several passes.
Crop Shear
The plate from roughing mill will have minor fish tail at leading and tailing ends.
This portion has to be removed in order to have a square ends. Crop shear chops
off the fish tail ends.
Steckel Mill
This is also a reversible mill with level 2 automation. This is the main unit of
HRM Complex. The plates that enter this mill from roughing mill will further be
rolled down to the scheduled/ planned thickness . To compensate for the heat
loss during rolling, the mandrel is housed inside reheating furnace. LPG is used
for heating the strip. This helps in relieving the stress induced, to some extent, in
the strip due to rolling. When the final required thickness is reached, the strip
travels over a roller run table. The bring down the temperature of the strip;
laminar cooling towers are installed above the run table, which showers water at
rated pressure on the strip.
Down Coiler
The strip from the steckel mill is wound on the mandrel and if forwarded to the
Numbering/ strapping machine.
Numbering and Weighing Machine
To avoid unwinding of the coils, they need to be strapped. Since the coil will be
hot condition, manual strapping is not possible. Hence an automatic strapping
machine which will bind the straps together over the coil. The numbering
machine prints the following parameters on the strip (spray painting method):
 Grade
 Thickness
 Width
 Coil number
The coil is also weighed in the weighing machine and the weight also is
marked on the strip.

12. 9
2.1.2. CRM: Cold Rolling Mill
Cold Rolling Mill complex is equipped with the most modern stainless steel
production lines, sourced from leading manufacturers of the world. Coil build up
line, bell anneal furnaces continuous annealing & pickling lines, Sendzimir mills,
skinpass mill, strip grinding line, slitting & shearing lines to produce coils
/sheets with precise dimensional tolerance & flatness with superior metallurgical
characteristics.
Input
a) Hot rolled stainless steel coils from hrm to ssp.
b) Imported source hot rolled coils (430 grade coils).
Output
Stainless steel coils and sheets of various sizes as mentioned in the marketing
and metallurgical services manual. The very purpose of any industry is to
produce an end product that has a wide range market.
PROCESS FLOW :COLD ROLLING MILL
1. Hot rolled coil 15. Requiring shear
2. Coil buildup line 16. Coil packing line
3. Annealing & pickling line 17. Blanking line
4. Bell annealing furnace
5. Sendzimir mills
6. Strip grinding line
7. Skin pass mill
8. Shearing line
9. Slitting line
10. Coil inspection & dividing line
11. Sheet grinding & polishing line
12. PVC coating unit
13. Sheet packing line
14. Strecher leveler

13. 10
COLD ROLLING MILL FLOWCHART

14. 11
Functions of each unit CRM
Coil Build Up Line
Coil Build Up Line are used to increase coil diameters by welding smaller coils
together. Generally these lines are used in non ferrous industries. This permits
increased production running time of subsequent process and avoid end losses of
smaller coils thereby improves yield. Welding of coils is done by thyristor
controlled DC TIG welder. The welding joints are roll able.
Annealing & pickling line
The entry of an APL has a small sealing followed by a Preheating Furnace (PF).
The strip is heated by waste gas coming from the Direct Fired Furnace (DFF), in
the DFF strip is further heated to the required annealing temperatures and hold
for certain soaking time. Strip is supported inside furnace by up-down rollers.
After the annealing section, the strip enters a air cooling section followed by a
water quench for final cooling and a wringer roller.In the continuous pickling
line the scale that forms on the hot strip during hot rolling is rinsed with
hydrochloric acid. This creates a bare metallic strip surface. To ensure an
uninterrupted pickling process, the continuous pickling line features a strip
accumulator, also called a looper. The strip is accumulated to avoid
unintentional standstill or operational stops, e.g. for coil welding.
Sendzimir mills
A Z-Mill or Sendzimir Mill is a machine for rolling steel. Unlike a
traditional rolling mill this 20-high cluster mill configuration utilizes cascaded
supporting rolls to apply force on the small work rolls in the center. This allows
the application of a higher roll pressure without bending the work rolls, which
would result in poor metal quality. Thus very hard and elastic materials can be
rolled
Skin pass mill
After annealing, the coils are re-rolled in a skin-pass (or temper) mill. This
ensures that the strip obtains the mechanical and technological properties

15. 12
required. A skin-pass mill consists of a decoiler with a transfer table, a
straightener, usually two rolling stands, a tension leveller and a recoiler.
Skin-pass mills are usually equipped with four-high or multi-roll stands. All
rolling stand components are exposed to high temperatures, strong mechanical
stress and other extreme operating conditions.
Shearing line
Here,the coils are cut in the form of sheets according to the customer’s
requirement.
Slitting line
Here,the coils are cut in the form of coils according to the customer’s
requirement.
Blanking line
A flat sheet of material is not actually produced by a mill as a flat sheet. In
reality, a flat sheet of material starts its life as part of a coil of
material. A Blanking Line will uncoil the material, level it, and then cut it to
the required length and stack it. The end product produced by a Blanking Line
is a flat sheet of material cut to a very precise length tolerance.This is used to
produce Coin blanks according to the desired size and thickness.

16. 13
3. CONCLUSION
For a Mechanical Engineering student, a learning combination of theory and
practical experience is an valuable asset which helps in understanding the core
principles of manufacturing by the way of first hand experience.
This industrial training in Salem Steel Plant has given me such a great
experience about all the production processes, which is going on in the
company.
It also helped me to understand the exact mechanism of working of the various
departments.