Peoples Steel Mills Karachi Internship Report

Internship
Report
Peoples Steel Mill Ltd Karachi

DAWOOD, UET, KARACHI
CHEMICAL ENGINEERING-17
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Contents
PREFERENCES.......................................................................................................................4
ACKNOWLEDGEMENT ...........................................................................................5
Introduction to Industry: ............................................................................................6
What is Steel?................................................................................................................6
Chemical composition of Steel....................................................................................7
M-SHOP (Melting):..................................................................................................... 10
I. Scrap Yard:................................................................................................................... 10
HMS SCRAP: .............................................................................................................................................11
BUNDLES SCRAP:....................................................................................................................................12
SHREDDED SCRAP:................................................................................................................................12
RAIL & WHEEL SCRAP: ..........................................................................................................................13
II. Electric Arc Furnace (EAF):..................................................................................... 14
Operation of an Electric Arc Furnace:................................................................................................15
Scrap charging .........................................................................................................................................15
Melting.......................................................................................................................................................16
Slag Formation: .......................................................................................................................................18
Tapping Steel............................................................................................................................................19
III. Ladle Furnace: ......................................................................................................... 19
1. Rinsing /Purging:.................................................................................................................................20
2. Alloying .................................................................................................................................................20
3. Refining:................................................................................................................................................23
IV. Vacuum Degassing (VD):........................................................................................ 24
1. Water Pump:.........................................................................................................................................25
2. Steam Ejectors: ....................................................................................................................................25
V. Vacuum Oxygen Decarburization (VOD)................................................................. 25
VI. Continuous Casting (CC):....................................................................................... 26
1. Process: ..................................................................................................................................................26
2. Tundish: ................................................................................................................................................27
3. Mould:....................................................................................................................................................28
4. Products: ...............................................................................................................................................28
VII. Ingot Casting (IC):................................................................................................... 28
Bottom Pouring:......................................................................................................................................29
I.C Moulds:................................................................................................................................................30
ROLE OF REFRACTORY IN PSM:............................................................................... 31
1. What is Refractory?......................................................................................................... 31
1. Acidic Refractory:...........................................................................................................................31
2. Basic Refractory:.............................................................................................................................31
3. Neutral Refractory: ........................................................................................................................32
2. REFRACTORY DEVELOPMENT CENTRE: .................................................................... 32

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I. Magnesia Carbon Bricks:...........................................................................................................32
II. High Alumina Bricks: ....................................................................................................................33
III. Insulation Bricks:.......................................................................................................................34
IV. Electric Arc Furnace Refractory Lining:................................................................................34
V. Ladle Refractory Lining: ...............................................................................................................34
VI. Tundish Refractory Lining:......................................................................................................35
R-SHOP (Forging):...................................................................................................... 35
Forging: (R-1) ...................................................................................................................... 35
Open Die Forging....................................................................................................................................36
Closed Die Forging: ................................................................................................................................36
Machinery:................................................................................................................................................36
Input:..........................................................................................................................................................37
Output: ......................................................................................................................................................37
Press Forging (R-3):............................................................................................................ 37
Input:..........................................................................................................................................................37
Output: ......................................................................................................................................................37
Machinery:................................................................................................................................................38
LONG FORGING MACHINE (P-1)...................................................................................... 38
Characteristic:..........................................................................................................................................38
Input:..........................................................................................................................................................39
Output: ......................................................................................................................................................39
Machinery: ................................................................................................................................................39
Q-SHOP (Bar-Rolling)................................................................................................ 40
Roughing Mill/ Hot Rolling Mill: ..................................................................................... 40
Finishing Mill: .................................................................................................................... 40
N-SHOP (Rolling):....................................................................................................... 41
Rolling:................................................................................................................................ 41
Input:................................................................................................................................... 41
Output:................................................................................................................................ 42
Peeling Bay: ................................................................................................................. 42
1. Slab Grinder................................................................................................................. 42
2. Billet Grinder .............................................................................................................. 42
3. Hand Grinder: ............................................................................................................. 42
WATER TREATMENT PLANT: .................................................................................... 42
Water Treatment:............................................................................................................... 42
Chemical Treated Water Supply:...................................................................................... 43
Treatment ........................................................................................................................... 43
Quality Assurance Department (QAD).................................................................... 44
1. Workshop: ....................................................................................................................... 44
2. Optical Emission Spectrometer.................................................................................... 44

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3. XRF-Spectrometer ....................................................................................................... 46
3. Wet Chemical Analysis:.................................................................................................. 47
4. Mechanical Analysis....................................................................................................... 48
1. Hardness.......................................................................................................................... 48
5. Metallography:................................................................................................................ 49

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PREFERENCES
This report is submitted by the students of
Chemical Engineering, Dawood University of
Engineering And Technology, Karachi to the
QAD, Peoples Steel Mill ltd. Karachi. The
students have visited all unit shops of
industry to gain first-hand knowledge. We
have tried to summarize our knowledge
regarding internship in this report.

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ACKNOWLEDGEMENT
We are greatly thankful to Mr. Pervaiz Khan, Director of DILAA,
Dawood University of Engineering & Technology, Karachi and Mr.
Nasir Hussain HR Executive, Mr. Nasir Head of QAD and Mohsin
Mumtaz for this golden opportunity of availing internship in
Peoples Steel Mill Karachi.
Specially thanks to our instructors:
o Mr. Munawar Ali Chandio (QAD)
o Mr. Jahanzaib (EAF-1)
o Mr. Muhammad Shahid (Wet Chemical Analysis)
o Mr. Zeeshan (QAD)
o Mr. Asiif Shahid (Tundish Refractory)
o Mr. Mudassir (P-2 Shop)
o Mr. Sohaib (W-Shop)
o Mr. Imran (WTP)
o Mr. Javed (RDC)
o Mr. Farhan (Workshop-QAD)
o Mr. Mushtaq (R-3)
o Mr. Noman (Q-Shop-QAD)
o Mr. Tariq Hussain (OES-QAD)
o Mr. Asim (Scrapyard)
o Mr. Shabir (N-Shop)
We are also thankful to all staff and workers of PSM to
cooperate with us in great way.

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Introduction to Industry:
Peoples Steel Mill Limited set up by government of Pakistan, is a special
and alloy steels production facility. The plant is located in Javedan Nagar
Manghopir, Karachi, having area of 500 sq.meters. The plant originally set-
up in 1974 with Japanese technology. PSM is now equipped with a modern
melting refining degassing, electro slag-re-melting, necessary casting,
rolling and forging facilities. Industry has yearly 70,000 MT in the form of
ingots, billets, plates, bars, flats, forgings and casting. PSM is
manufacturing more than 300 grades of special and high steel alloys. Mostly
are:
Special Carbon Steels
Free / Semi Free Cutting Steels
Case Hardening Steels
Spring Steels
Ball bearing Steels
Heat Resisting Steels
Cutting Tool Steels
High Speed Steels
Hot work & Die Steels
Stainless / Surgical Steels
Armour Steels
Steels for Special Applications
What is Steel?
Steel, alloy of iron and carbon in which the carbon content ranges up to 2 percent.
Because of its high tensile strength and low cost, it is a major component used
in buildings, infrastructure, tools, ships, automobiles, machines, appliances,
and weapons. Iron is the base metal of steel. Iron is able to take on two crystalline
forms (allotropic forms), body centered cubic and face centered cubic, depending
on its temperature. In the body-centered cubic arrangement, there is an iron
atom in the center and eight atoms at the vertices of each cubic unit cell; in the
face-centered cubic, there is one atom at the center of each of the six faces of the
cubic unit cell and eight atoms at its vertices. It is the interaction of the allotropes
of iron with the alloying elements, primarily carbon that gives steel and cast iron

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their range of unique properties. The carbon in typical steel alloys may
contribute up to 2% of its weight. Varying the amount of carbon and many other
alloying elements, as well as controlling their chemical and physical makeup in
the final steel slows the movement of those dislocations that make pure iron
ductile, and thus controls and enhances its qualities. These qualities include such
things as the hardness, quenching behavior, need for annealing, tempering
behavior, yield strength, and tensile strength of the resulting steel. The increase
in steel's strength compared to pure iron is possible only by reducing iron's
ductility.
Some elements are intentionally added to iron for the purpose of attaining
certain specific properties and characteristics. Other elements are present
incidentally and cannot be easily removed. Such elements are referred to as
“trace” or “residual” elements. There are thousands of steel alloys and their
categorization is complex and varies by governing body. Most, however, can be
broadly grouped into Plain Carbon Steel, Ultra Low Carbon (ULC) Steel, High
Strength Low Alloy (HSLA) Steel, Alloy Steel, High Alloy Steel (including
Stainless Steel and Tool Steel) and Electrical Steel. Advanced High Strength Steel
(AHSS) is the newest classification of steels. Alloying elements often serve
different purposes in different steels. For example, Manganese contributes to
steel’s strength and hardness in the as rolled condition but another important
characteristic is its ability to increase hardenability which is critical in heat
treating. The effect of alloying elements on steel properties is a huge subject. The
following is a very cursory summary of the influence of the above elements in
common flat rolled products. More information may be found on the websites
of governing bodies and materials information societies such as ASM
International.
Chemical composition of Steel
1. Carbon:
Carbon is the principal hardening element in steel. Hardness and strength
increase proportionally as Carbon content is increased up to about 0.85%.
Carbon has a negative effect on ductility, weldability and toughness. Carbon
range in ULC Steel is usually 0.002 – 0.007%. The minimum level of Carbon
in Plain Carbon Steel and HSLA is 0.02%. Plain Carbon Steel grades go up to
0.95%, HSLA Steels to 0.13%.

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2. Manganese:
Manganese is present in all commercial steels as an addition and
contributes significantly to steel’s strength and hardness in much the same
manner but to a lesser degree than carbon. Manganese improves cold
temperature impact toughness. Increasing the Manganese content decreases
ductility and weldability. The typical Manganese content is 0.20 – 2.00%.
3. Phosphorus:
Phosphorus is most often a residual but it can be an addition. As an
addition it increases hardness and tensile strength. It is detrimental to
ductility, weldability and toughness. Phosphorus is also used in re-
phosphorized high strength steel for automotive body panels. Typical
amounts as a residual are less than 0.020%.
4. Sulphur:
Sulphur is present in raw materials used in iron making. The steelmaking
process is designed to remove it as it is almost always a detrimental impurity.
A typical amount in commercial steel is 0.012%, and 0.005% in formable
HSLA.
5. Silicon:
Silicon can be an addition or a residual. As an addition it has the effect of
increasing strength but to a lesser extent than Manganese. A typical minimum
addition is 0.10%. For post galvanizing applications the desired residual
maximum is 0.04%.
6. Copper, Nickel, Chromium, Molybdenum and Tin:
Copper, Nickel, Chromium (Chrome), Molybdenum (Moly) and Tin are
the most commonly found residuals in steel. The amount in which they are
present is controlled by scrap management in the steelmaking process.
Typically the specified maximum residual quantities are 0.20%, 0.20%, 0.15%
and 0.06% respectively for Copper Nickel, Chromium and Molybdenum but
the acceptable limits depend mainly on product requirements. Copper,
Nickel, Chromium and Molybdenum, when they are additions, have very
specific enhancing effects on steel. A Tin residual maximum is not usually
specified but its content in steel is normally kept to 0.03% or less due to its
detrimental characteristics.

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7. Vanadium, Columbium and Titanium
Vanadium, Columbium and Titanium are strengthening elements that are
added to steel singly or in combination. In very small quantities they can have
a very significant effect hence they are termed micro-alloys. Typical amounts
are 0.01 to 0.10%. In Ultra Low Carbon Steel Titanium and Columbium are
added as “stabilizing” agents (meaning that they combine with the Carbon
and Nitrogen remaining in the liquid steel after vacuum degassing). The end
result is superior formability and surface quality.
8. Aluminum:
Aluminum is used primarily as a deoxidizing agent in steelmaking,
combining with oxygen in the steel to form aluminum oxides which can float
out in the slag. Typically 0.01% is considered the minimum required for
“Aluminum killed steel”. Aluminum acts as a grain refiner during hot rolling
by combining with Nitrogen to produce aluminum-nitride precipitates. In
downstream processing aluminum-nitride precipitates can be controlled to
affect coil properties.
9. Nitrogen:
Nitrogen can enter steel as an impurity or as an intentional addition.
Typically the residual levels are below 0.0100 (100 ppm).
10. Boron:
Boron is most commonly added to steel to increase its hardenability but in
low carbon steels it can be added to tie up Nitrogen and help reduce the Yield
Point Elongation thus minimizing coil breaks. At the same time, when
processed appropriately, the product will have excellent formability. For this
purpose it is added in amounts up to approximately 0.009%. As a residual in
steel it is usually less than 0.0005%.
11. Calcium:
Calcium is added to steel for sulphide shape control in order to enhance
formability (it combines with Sulphur to form round inclusions). It is
commonly used in HSLA steels especially at the higher strength levels. A
typical addition is 0.003%.

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M-SHOP (Melting):
Manufacturing of Steel is commonly done with two methods; one is from iron
ore and the second is Scrap (Recycled Steel) as raw material. PSM is totally
producing steel from Scrap. In industry there are different units for different
stages for Steel manufacturing. So we visited all units step by step to acquire
advance knowledge of Steel making.
I. Scrap Yard:
Our first visit to M-Shop, a unit of industry where basic steel making process is
proceed. From Melting to casting all particulars are done in M-Shop unit. Scrap
yard is also part of M-Shop.
Steel Scrap:
Steel scrap consists of discarded steel or steel products. Iron and steel is a
valuable feedstock in producing new steel products. Steel is a unique material as
it always contains recycled steel. Every year, millions of tons of pre- and post-
consumer steel products, including used steel cans, automobile and construction
materials, appliances, are recycled by steel mills into every ton of new steel
manufactured. In fact, with the exception of the earliest methods of steel making,
recycling has always been an integral part of the production of steel. Steel is 100
per cent recyclable. It can be reused over and over again without any loss of
quality. Scrap is therefore a valuable raw material for steel production. Steel is
not only 100 per cent recyclable, it is also a very durable material that can be in
use for decades or even for centuries.
The following are the facts associated with steel scrap and its recycling.
 Almost 40 % of the global steel production is made from steel scrap.
Around 500 million tons of steel scrap is being used annually for the
production of steel.
 Recycling of one ton of steel saves 1.4 tons of iron ore, 0.40 tons of coal,
and 0.055 tons of limestone.
 CO2 emissions are reduced by 58 % through the use of steel scrap.
 Recycling one ton of steel scrap saves 2.3 Cu m of landfill space.
 Recycling of steel scrap uses 75 % less energy compared to creating steel
from raw materials.
 Steel scrap recycling uses 90 % less virgin materials and 40 % less water. It
also produces 76 % fewer water pollutants, 86 % fewer air pollutants and
97 % less mining waste.

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 Steel automobile frames contain at least 25 % recycled steel scrap and a
typical electrical appliance will usually be made of 75 % recycled steel
scrap. Steel cans consist of at least 25 % recycled steel scrap.
There are more than 2000 types of scraps in the world used for steelmaking but
PSM manufacture steel using 4 types of scrap.
1. Heavy Metal Scrap
2. Bundle Scrap
3. Shredded Scrap
4. Rail & Wheel Scrap
HMS SCRAP:
Heavy melting steel (HMS) or heavy
melting scrap is a designation for
recyclable steel and wrought iron. It
may and will consist of cut lengths of
pipe, re-bar, angles, steel poles, H or
I beams, ships plate. It is broken up
into two major categories: HMS 1 and
HMS 2, where HMS 1 does not
contain galvanized and blackened
steel, whereas HMS 2 does. The Institute of Scrap Recycling Industries
(ISRI) breaks up the categories further.
 ISRI 200 (HMS 1): Wrought iron or steel scrap 1
⁄4 inch (6.35 mm) and larger in
thickness. All pieces must be smaller than 60 in × 24 in (1,524 mm × 610 mm)
 ISRI 201 (HMS 1): Same as ISRI 200 except pieces must be smaller than 36 in
× 18 in (914 mm × 457 mm).
× 18 in (1,524 mm × 457 mm).
 ISRI 203 (HMS 2): Wrought iron or steel scrap, black and galvanized, 1
⁄8 inch
(3.175 mm) and larger in thickness.
 ISRI 204 (HMS 2): Same as ISRI 203 except pieces [1]
must be smaller than 36 in
× 18 in (914 mm × 457 mm).
 ISRI 205 (HMS 2): Same as ISRI 204 except it may contain automotive scrap
except for thin gauge material.
× 18 in (1,524 mm × 457 mm).

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BUNDLES SCRAP:
Bundle consists of new black steel sheet scrap, clippings or skeleton scrap that
are compressed into a bundle of not less than 75 pounds per cubic foot, so that
the material can be handled with a
magnet. It may include black,
galvanized and zinc coated materials
whose dimensions must not exceed
4’x2’x2’. #1 Bundles may include Stanley
balls or mandrel wound bundles or
skeleton reels, tightly secured. It may
also include chemically detained
material. Wrought iron and/or steel
scrap above 1/8 inch in thickness
compressed to charging box size and weighing not less than 75 pounds per cubic
foot and free of all metal-coated material can be classified under #1 Bundle scrap.
Bundle must not contain metal coated, limed, vitreous enameled and electrical
steel containing more than 0.5% silicon. It may not include old auto body or
fender stock.
As per the latest Scrap Specifications Circular 2017 released by the Institute of
Scrap Recycling Industries (ISRI), Bundle steel scrap are referenced by codes 208,
217 and 235.
SHREDDED SCRAP:
Shredded scrap is a large part of the
recycling industry and can be utilized in
multiple circumstances. The classification
of shredded scrap is outlined to give a
better understanding of what goes into this
category. The shredded scrap grade
consists of homogeneous iron and steel
scrap, which is magnetically separated,
originating from automobiles, including
but not limited to unprepared no. 1 and no. 2 steel, miscellaneous baling, and
sheet scrap. For shredded scrap, the average density ranges from fifty (50)
pounds per cubic foot, to seventy (70) pounds per cubic foot, as specified by the
Institute of Scrap Recycling Industries.

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RAIL & WHEEL SCRAP:
Unused rails and wheel of trains are recycled in PSM for the steelmaking.
Railroad scrap (wheels, axles, parts of locomotives and carriages. Railroad rail cut
2 to 4 feet in length, may include joint bars and splices. May be broken, sheared
or torch cut to size. All other railroad scrap including bolsters, side frames, car
sides and roofs, railroad rail, brakes, linkages, cast iron in any form, manganese
in all forms.
All these scrap are imported from UAE, England, South Africa, and European
countries. Scrap is stored in scrap yard and before charging all types of scrap is
cut into pieces of 3-4 feet of length and this purpose of cutting is for easy and best
way to melt in furnaces because small size is easy to melt and occupy less area in
furnaces. The scrap is weighted in Buckets with the help of Scrap Carrier
Magnets. There are nine buckets with different capacity and weight mentioned
below.
1. Bucket-A 6170 kg
2. Bucket-B 6055 kg
3. Bucket-C 6330 kg
4. Bucket-D 6295 kg
5. Bucket-E 6040 kg
6. Bucket-F 6175 kg
7. Bucket-G 2375 kg
8. Bucket-H 6030 kg
9. Bucket-I 5655 kg
The scrap is charged to furnaces with its requirement and need. The scrapyard
operator is always linked to the furnaces operators for their requirement and
desire. The scrap is send on their choice. The scrap is not loaded with single type,

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also it is loaded in bucket with all mixing scrap. Shredded scrap is loaded at
bottom in bucket for easy charging, after then different types of scrap with
minimum required size and length. In one heat, all different types of scrap is
charged, because the percentages of elements are different with different types
of scrap, some scrap have high percentage of required elements of steelmaking
and some have less, so it will be easy to load different types so requirement is
achieved easy.
The melting process is also done in M-Shop. For the melting of scrap there
are two Electric Arc Furnaces (EAFs) are installed in M-Shop in PSM.
II. Electric Arc Furnace (EAF):
An electric arc furnace (EAF) is a furnace that heats charged material by means
of an electric arc. Arc furnaces differ from induction furnaces in that the charge
material is directly exposed to an electric arc and the current in the furnace
terminals passes through the charged material. The main advantage of the
Electric Arc Furnaces over the Basic Oxygen Furnaces (BOF) is their capability to
treat charges containing up to 100% of scrap. About 33% of the crude steel in the
world is made in the Electric Arc Furnaces (EAF). This furnace is AC type. The
capacity of furnace is 15 ton. The temperature of furnaces varies up to 1700o
C.
Construction:
The furnace consists of a spherical hearth (bottom), cylindrical shell and a
swinging water-cooled dome-shaped roof.
The roof has three holes for consumable graphite electrodes held by a clamping
mechanism. The mechanism provides independent lifting and lowering of each
electrode.
The water-cooled electrode holders serve also as contacts for transmitting
electric current supplied by water-cooled cables (tubes). The electrode and the
scrap form the star connection of three-phase current, in which the scrap is
common junction.
The furnace is mounted on a tilting mechanism for tapping the molten steel
through a tap hole with a pour spout located on the back side of the shell.
The charge door, through which the slag components and alloying additives are
charged, is located on the front side of the furnace shell. The charge door is also
used for removing the slag (de-slagging). Here is the components of furnace:
 The Shell: The Shell is wall of furnace made up of metal.
 The Top: The top cap is fitted with walls of water circulating system and
inlet for 3 electrodes. Bottom of cap is pasted with castabales material as a
refractory purpose.

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 The Bottom: The bottom is also covered with refractory bricks of High
Alumina with pasting of Magnesite Mass.
 Refractory Bricks: After shell there is 1.5” thick line of Magnesite Mass
with lining of Magnesia Carbon Bricks.
Figure 1.1: Electric Arc Furnace
Operation of an Electric Arc Furnace:
There were two furnaces on working at that time we entered in the M-Shop, We
were lead to the Electric Arc Furnace-1, where Sir Jahanzaib has instructed all
about the process very well. The following steps are observed;
 Scrap charging;
 Melting;
 Refining;
 Slag Formation
 Tapping the steel;
Scrap charging
Scrap charging is batch process. Scrap is charged for one heat of furnace is mostly
in 2-3 steps. One bucket carrying scrap weight roundly about 5-6 ton is loaded in
furnace for heating. Total 3 buckets are charged for one heat in furnace. The scrap
used in charging is mix up, shredded scrap is used for bottom feeding and then
HMS is used for melting, because it will be easy to melt light weight metal first
with starting temperature and using shred type scrap will also not affect the

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furnace. Using scrap for steel making purpose is it is Controllable and Quality
of Steel.
Note: One Heat is equal to the process of furnace from charging to tapping.
Melting
Melting process starts at low voltage (short arc) between the electrodes and the
scrap. The arc during this period is unstable. In order to improve the arc
stability small pieces of the scrap are placed in the upper layer of the charge.
The electrodes descend melting the charge and penetrating into the scrap
forming bores. The molten metal flows down to the furnace bottom.
When the electrodes reach the liquid bath the arc becomes stable and the
voltage may be increased (long arc). The electrodes are lifting together with the
melt level. Most of scrap (85%) melt during this period. The electrodes used for
arcing is made of Graphite and there are three electrodes in Electric Arc
Furnace, graphite is used because it has high melting strength. The temperature
of furnaces starts varying from 15000
C to 17000
C. Diameter of one graphite
electrode is 12 inch. Mostly three buckets are charged with interval of Half an
hour time for complete melting.
Refining:
Different composition of scrap are stored in one furnace. There are different
composition like Carbon, Magnesite, Sulpher, Phosphorus, Oxygen, Silicon,
Nickel, etc. In refining there are chemical reaction occurs with the help of
oxygen lancing.
 Decarburization
 Dephosphorization
 Oxidation Reactions
1. Decarburization:
Decarburization is a surface degradation phenomenon in the forging and heat
treating of steels. Decarburization may be described as a metallurgical process in
which the surface of steel is depleted of carbon, by heating above the lower
critical temperature or by chemical action. Steel forgings are usually
decarburized. This process can happen as a side effect during a process, or can
be performed intentionally. The amount of carbon contained in a metal
influences its hardness. During decarburization, the carbon diffuses from the
surface of the metal, thus weakening the metal. This diffusion increases at higher

17
temperatures. The effect of decarburization not only brings down the strength,
but also increases the shear strain below the metal surface. The fatigue resistance
is decreased while the rate of crack growth and wear rate is increased. In plain
carbon steel, the carbon content will decrease until the ferrite layer is reached,
after which decarburization is inhibited by the ferrite layer. Excessive
decarburization will lead to defective products. Decarburization can be
detrimental or advantageous depending on the application for which the
decarburized steel is used for.
The reaction observed in furnace is;
C + O2 CO2
2. Dephosphorization:
Phosphorus can be removed both under oxidizing as well as reducing
conditions. But removal of phosphorus under reducing conditions is not
practical since its removal is highly hazardous. Thus phosphorus removal is
practiced mostly under oxidizing conditions.
2P + 5O P2O5
Phosphorus pentoxide is unstable in slag at higher temperature we add lime
(CaO) to stabilize the phosphorus pentoxide;
By adding the lime the reaction occur is;
CaO + P2O5 CaP2O5
This compound CaP2O5 is formed as a slag and removed by other slag
compound.
Through Oxygen lancing excess amount of Silicon, Aluminum, Maganasite are
also removed through slag formation.
3. Oxidation Reactions:
The principle reactions in steelmaking comprise of oxidation of impurity
elements by oxygen dissolved in hot metal or FeO content of slag.
(1)
(2)
(3)
(4)

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(5)
 All reactions are exothermic.
 C is removed as gas.
 Except C, all other impurities are removed as oxides and all these oxides
float on the surface of the molten metal during refining of hot metal to
steel.
 Iron oxidation is unavoidable. Oxidation of Fe is loss in productivity;
hence its oxidation must be controlled.
 Oxygen must be dissolved to remove an impurity from the hot metal.
Slag Formation:
During the steel production a considerable amount of slag is produced.
Physical properties:
Steel making slag aggregates are highly angular in shape and have rough surface
texture. They have high bulk specific gravity and moderate water absorption (less
than 3 percent). Typical physical properties of steel making slag are as follows:
 Specific gravity – > 3.2
 Bulk density – 1.6 – 1.9 tons per cubic meter
 Absorption – Up to 3 %
Chemical properties:
The chemical composition of steel making slag is usually expressed in terms of
simple oxides calculated from elemental analysis determined by x-ray
fluorescence. The following is the range of compounds present in steel making
slag from a typical base oxygen furnace. Virtually all SMS slags fall within these
chemical ranges but not all steel making slags are suitable as aggregates. Of more
importance is the mineralogical form of the slag, which is highly dependent on
the rate of slag cooling in the steel making process. The following composition is
formed within slag:
CaO SiO2 MgO Al2O3
MnO FeO P2O5 S
Steel making slag is mildly alkaline, with a solution pH generally in the range of
8 to 10. However, the pH of leachate from steel making slag can exceed 11, a level
that can be corrosive to aluminum or galvanized steel pipes placed in direct
contact with the slag.

19
Uses of steel making slag:
Steel making slag is recycled in sinter plant as sinter feed since it has high
percentage of CaO and MgO. It is used as railroad ballast and as a road base. Steel
making slag is also used for soil treatment, hot mix asphalt and as a land fill.
Tapping Steel
After 2 hour of process of melting, a sample is taken for composition analysis and
after perfection of composition result, then tapping process is done, tapping is
done in ladle. Before starting tapping, ladle is poured slightly with Chroma Based
Sand for protection of damaging plates.
Partial addition of ferroalloys before tapping is processed. Ladle is preheated to
avoid shocking of molten steel. Ferroalloys are added partially according to grade
that is being made on furnace. The listed below ferroalloys are used;
 Ferromagnetic
 Ferrosilicon
 Silicon chrome
 Ferrochrome
 Silico manganese
As completion of tapping the ladle is send to ladle furnace for further treatment.
III. Ladle Furnace:
A ladle furnace is used to relieve the
primary process of steel making of
many of the secondary refining
operations. The temperature of ladle
furnace for holding process is 1630-
500
C and maximum temperature for
finalizing the process is 17000
C. For
Low Grade Carbon high temperature
is required.
The main functions of a ladle furnace
are as follows.
 Reheating of liquid steel by electric
power which is conducted by
graphite electrodes.
 Homogenization of steel temperature and chemistry through inert gas
rinsing.

20
 Formation of slag layer that protects refractory from arc damage,
concentrates and transfer heat to the liquid steel, trap inclusions and metal
oxides, and provides means for desulphurization.
 Additions of ferro alloys to provide for bulk or trim chemical control.
 Cored wire addition for trimming and morphology control.
 Provide a means for deep desulphurization.
 Provide a mean for dephosphorization.
 Act as a buffer for downstream equipment and process.
1. Rinsing /Purging:
For achieving a homogeneous bath temperature and composition, the steel in the
ladle is normally rinsed by means of argon/nitrogen gas bubbling. For moderate
gas bubbling rates (e.g. less than 0.6 N cum/min) porous refractory plugs are
used, usually mounted in the bottom of the ladle. The function of the porous plug
is to provide gas stirring of the molten metal to promote homogenization.
Normal stirring operations are performed by percolating argon gas through the
porous plug. At ladle furnace the purging of nitrogen is very effective and very
economically as compared to argon.
2. Alloying
Alloying of ferroalloys is mandatory as per grade requirement. According to steel
grade or specialty the alloying is processed.
The following ferroalloys are used for alloying;
Ferroalloys are master alloys containing iron and one or more non-ferrous metals
that are used as the most economical way to introduce an alloying element in the
steel melt. Their main benefits are an improvement in steel tensile strength,
regular strength and resistance to wear and tear and corrosion. All of this is
achieved by:
 A change in the chemical composition of the steel
 The removal of harmful impurities such as Sulphur, nitrogen or oxygen
 A change in the solidification process, for example, upon inoculation.

21
1. Ferrosilicon:
This product has many applications in steel production and casting. It
contributes an increase in hardness and
deoxidizing properties but also with an
improvement in strength and quality of iron
steel products. Using it to manufacture
inoculants and modularizes can give specific
metallurgical properties to the final products
produced, which can be:
 Stainless steel: for superior corrosion
resistance, hygiene, aesthetic and wear-
resistance qualities
 Carbon steels: used extensively in suspension bridges and other structural
support material and in automotive bodies
 Alloy steel: other types of finished steel
2. Ferro Manganese:
Ferro manganese is an alloy of iron and manganese
containing usually about 80% manganese. Ferro
manganese is used mainly to counteract the bad
effects of sulfur. It also acts as a deoxidizer and
combines with sulfur, thereby improving the hot-
working properties of the product. It imparts
metallurgical properties such as increased strength,
hardness toughness and hardenability.
There are two types of Ferro Manganese are used one is High Carbon and Second
is Low Carbon, that use is with respect to carbon requirement in respective grade.
3. Ferro Chrome:
Ferrochrome, or Ferrochromium (FeCr) is a type of ferroalloy, that is, an alloy
between chromium and iron, generally containing 50% to 70% chromium by
weight. Over 80% of the world's ferrochrome is utilized in the production of
stainless steel. In 2006 28 Mt of stainless steel were produced. Stainless steel
depends on chromium for its appearance and its resistance to corrosion. The
average chrome content in stainless steel is approximately 18%. It is also used
when it is desired to add chromium to carbon steel. FeCr from Southern Africa,

22
known as "charge chrome" and produced from a Cr containing ore with a low
carbon content, is most commonly used in stainless steel production.
Alternatively, high carbon FeCr produced from high grade ore found in
Kazakhstan (among other places) is more commonly used in specialist
applications such as engineering steels where a high Cr to Fe ratio and
minimum levels of other elements such as sulfur, phosphorus and titanium are
important and production of finished metals takes place in small electric arc
furnaces compared to large scale blast
furnaces.
For chrome addition the PSM also use
Stainless Steel Scrap (SS Scrap). Shredded
type of SS Scrap give 12% yield of chrome
for effective alloying.
4. Ferro molybdenum
Ferro molybdenum is an
important iron-
molybdenum metal alloy, with a
molybdenum content of 60-75% It is
the main source for molybdenum
alloying of HSLA steel.
Ferromolybdenum is an alloy formed
by combining iron and molybdenum.
It is an extremely versatile alloy used
primarily in high-strength low alloys
and stainless steels. It has numerous
beneficial properties and can be used
even in cast irons, some high-speed tool steels, and super alloy applications.
Adding ferromolybdenum to a material helps to improve weldability, corrosion
and wear resistance as well to increase ferrite strength.
5. Ferro Vanadium:
Ferro Vanadium is an alloy which is formed by combining iron and vanadium
with a vanadium content range of 35%-85%. Ferro Vanadium is a universal
hardener, strengthener and anti-corrosive additive for steels like high-strength
low-alloy (HSLA) steel, tool steels, as well as other ferrous-based products.

23
Ferro Vanadium was first used in the production of the Ford Model T and is
still used in the automobile industry today. Ferro Vanadium, as an additive to the
production process of ferrous metals, will impart several desirable properties
upon the resulting new compound. One of
the primary benefits of adding Ferro
Vanadium to an alloy is its stability against
alkalis as well as sulphuric and
hydrochloric acids. Additionally, the
adding of Ferro Vanadium to an alloy can
result in a steel product less susceptible to
corrosion of any type. Ferro Vanadium is
also used to reduce weight while
simultaneously increasing the tensile
strength of the material.
3. Refining:
The refining of steel in the ladle is broadly defined here as comprising of the
operations such as deoxidation, desulphurization, Dephosphorization,
controlled additions of alloying elements and inclusion modification.
The refining steel in the ladle is usually done by deoxidation of steel with ferro-
manganese, ferrosilicon, silico-manganese, and aluminum. The steel is first
deoxidized partially with silico manganese, ferromanganese, and/or ferrosilicon
followed by a final deoxidation with aluminum. Such a practice has several
advantages including minimization of nitrogen pick up, minimization of
phosphorus reversion and minimization of aluminum losses during primary steel
making.
In certain steel grades, a very low sulphur content is specified e.g. 20 ppm and
less. These low sulphur contents can only be achieved by steel desulphurization
in the ladle in the presence of a calcium aluminate slag when the steel is fully
killed. For the required degree of desulphurization to take place within a practical
time span, good mixing of steel and slag is essential. The rate, at which the
sulphur can be removed, is strongly recommended by the gas flow rate during
rinsing of steel. Another method for achieving very low sulphur content is by the
injection of fluxes into the ladle. A typical flux used for desulphurization contains
70 % CaO and 30 % CaF2. Desulphurization achieved through powder injection
is around 15 % faster than the desulphurization with a top slag only, combined
with the gas rinsing. Desulphurization of steel in the ladle is accompanied by a
decrease in the temperature of the steel bath and hence needed reheating.
Calcium treatment of liquid steel is normally adopted to modify the morphology
of the inclusions. As a result of the treatment with calcium, the alumina and silica

24
inclusions are converted to liquid calcium aluminates or calcium silicates.
These liquid inclusions are globular in shape because of sulphur tension effects.
This change in inclusion composition and shape is commonly known as inclusion
morphology control or modification. Since the boiling point of calcium is 1491
deg C, calcium is a vapour at the steel making temperature. Hence when adding
calcium to the liquid steel, special measures are required to be taken to ensure
its proper recovery in the steel bath. Calcium or calcium alloys are added to the
liquid steel bath at the greatest possible depth so as to make use of the increased
pressure from the ferrostatic head to prevent the calcium from evaporating.
Further calcium retention frequency decreases with increasing quantity of
calcium injected. The quantity of calcium to be injected has to be adjusted in
accordance with the degree of cleanliness of the steel and its total oxygen
content.
IV. Vacuum Degassing (VD):
During the primary steelmaking process, gases like oxygen (O2), hydrogen (H2)
and nitrogen (N2) dissolve in the liquid steel. These gases have a harmful effect
on the mechanical and physical properties of steel. Dissolved O2 from liquid steel
cannot be removed as molecular O2 and its removal is termed as deoxidation.
The term degassing is used for the removal of H2 and N2 gases from liquid steel.
Since the degassing process of liquid steel is carried out under vacuum, it is also
known as vacuum degassing of liquid steel. Vacuum degassing processes are
carried out in steel teeming ladles.
As molten steel in ladle brought to VD Area, First its covered with a cap and
sealed by Fire clay refractory. Purpose of vacuum is to remove gases for this the
internal pressure is reduce to 1 atm or 760 torr. For this purpose two pump are
used;
1. Water Pump: 2 Water Pumps
2. Stream Ejection Pump: 4 Stream Ejectors Pump
Purging in VD is done with Argon because of its affectivity. Fire Clay refractor
used for covering ladle cap gap to obtaining good vacuum. Sometimes that
covered are damaged by high temperature and over boiling occurs, when slag is
highly viscous and for this operator use Aluminum bar that reduce boiling rate.
For Desulphurization wiring casing is used. In Wire casing Wires of Calcium and
Silicon are introduced in process. Dolomite is also used for making slag viscous
and removable.

25
1. Water Pump:
One of the vacuum pump systems used for vacuum degassing combines both
steam ejectors with liquid ring pumps and involves putting several ejectors in
series, followed by the liquid ring pump. The liquid ring pump is considered a
positive displacement, wet style pump.
Like all wet style pumps, the liquid ring pump relies on a liquid to provide the
seal between the rotating vanes and the pump housing. In vacuum degassing
applications the pump is preceded by steam ejectors, which inject steam into the
system. This steam condenses in the condensation stage producing a liquid,
which is used as the pump seal.
2. Steam Ejectors:
Steam jet ejectors use the venturi principle to create a vacuum by forcing steam
through a nozzle. The nozzle provides controlled expansion of the steam, which
effectively converts pressure into velocity, producing a vacuum. This draws in
and entrains any gases present which enter at the bottom. The steam is mixed
with the pumped gases and passes out of the ejector.
Vacuum degassing plays a critical role in the manufacture of steel. The vacuum
degassing process allows the production of high quality, low carbon and ultra-
low carbon steels and stainless steels, with minimal oxygen, hydrogen, and
nitrogen contamination. The main benefits include:
 Reducing hydrogen content to avoid embrittlement of steel.
 Reducing oxygen content to enhance microcleanliness.
 Improving the distribution of alloying elements and other additives.
 Controlling the composition of the steel to tighter chemistry
specifications.
 Improving mechanical properties such as uniform transverse ductility,
fatigue resistance, and high temperature performance.
 Achieving exceptionally low carbon content steel heats beyond those
obtainable by conventional means.
V. Vacuum Oxygen Decarburization (VOD)
The VOD unit is mainly used for the production of stainless steel, it provides the
most suitable condition for extensive decarburization and achievement of high-
purity and cleanness. The unit is basically a tank degasser equipped with an
oxygen lance, but specifically configured to withstand the heat load from an
intense CO emission

26
It is normally used for deep decarburization of high alloy steel grades, usually
to remove carbon without affecting chromium content in the production of
stainless steel grades.).
VI. Continuous Casting (CC):
Continuous casting allows metals and alloys to be stretched, shaped and
solidified without the need for an interruption reducing waste while improving
yield, cost efficiency, and quality. About 55 percent of the world’s liquid steel
production is solidified in continuous casting processes, the most widely used of
which feeds liquid steel continuously into a short, water-cooled vertical copper
mold and, at the same time, continuously withdraws the frozen shell, including
the liquid steel it contains.
1. Process:
In continuous grid manufacturing, molten lead is ladled into the casting
machine, where it is then molded, cooled and stretched into the finished product.
Though different machines offer various advantages, the basic process is the
same. Here is how the process unfolds, step by step:
1. Liquid alloy is ladled into a tundish, which directs the flow of the material
into the mold. The tundish acts as a reservoir, continuing the flow of metal
while the ladle refills.
2. Right below a mold is attached with help of two small shroud pipe. Molten
Steel flow from tundish to mold for shaping. The mold has a particular
shape in it according to product shape.
3. The semi-solid grids are sent through the strand guide, continuing to
stretch the material to the desired thickness while cooling persists in the
secondary cooling stage.
4. The fully solidified grids are sent through straighteners, where they
achieve their final dimensions.
5. The finished grids are wound into a roll.
6. For cutting into desire length shearing machine are installed with it.

27
2. Tundish:
To transfer liquid steel from a teeming ladle to the continuous casting machine
mould, an intermediate vessel, called a tundish, is used. Tundish is a rectangular
big end up, refractory lined vessel. The tundish bottom has two nozzle ports with
stopper rod for controlling the flow of liquid steel. Tundish is often divided into
two sections namely (i) an inlet section, which generally has a pour box and
where liquid steel is fed from the steel teeming ladle, and (ii) an outlet section
from which liquid steel is fed into the continuous casting machine mould.
The continuous casting tundish serves as a buffer and links the discontinuous
process of the secondary steelmaking in the ladle with the continuous casting
process in the mould. It acts as a reservoir during the ladle change periods and
continues to supply liquid steel to the mould when incoming liquid steel is
stopped, making sequential casting by a number of ladles possible. The main
causes for inclusion formation and contamination of the liquid steel include
reoxidation of the liquid steel by air and carried over oxidizing ladle slag,
entrainment of tundish and ladle slag, and emulsification of these slags into the
liquid steel. These inclusions must be floated out of the liquid steel during its
flow through the tundish before being teemed into the mould.

28
The capacity of tundish is 6 ton. It is preheated at roundly 1200-1250o
C for
protecting of freezing liquid. Liquid can stay in tundish maximum 15 minutes
without being freezing. Ladle and tundish is connected with a refractory pipe
known as “Shroud”. In tundish two powder are used one is casting powder and
second is covering powder as a lubricant for reducing adhesive property.
Tundish Operations:
 To promote inclusion floatation by maximizing residence time
 To ensure inclusion assimilation by a captive and noncorrosive slag
 To reduce thermal and chemical losses from the liquid steel
 To minimize short circuiting and dead zones
 To offer the operator an optimal design for quality and yield.
3. Mould:
A mold or mould is a hollowed-out block that is filled with a liquid or pliable
material such as plastic, glass, metal, or ceramic raw material. The liquid hardens
or sets inside the mold, adopting its shape. A mold is the counterpart to a cast.
The mold is made of copper because of the high heat conductivity of that metal.
It is heavily water-cooled and oscillates up and down to avoid sticking of the
solidified shell to its walls. In addition, the mold wall is lubricated by oil or slag,
which is maintained on the steel meniscus and flows down into the gap between
mold and strand. The slag layer, when used, is formed by the continuous addition
of casting powder. Besides providing lubrication, it keeps air away from the liquid
steel, acts as a heat barrier, and absorbs inclusions. A Cobalt tube is fitted in
mould for level checking. Cooling in mould is referred as a primary cooling.
4. Products:
 Billet / Square Shape
o 110 mm
o 125 mm
o 150 mm
 Bloom / Square Shape
o 230 mm
VII. Ingot Casting (IC):
There are two types steel ingot casting
1. Top pouring 2. Bottom Pouring

29
Bottom Pouring:
PSM used bottom pouring method for ingot casting. There is a plate on which
different shape of moulds are placed for bottom pouring. In the centre a mould
is place called trumpet. Trumpet has also refractory lining and cap on it known
as Funnel. From bottom of ladle molten steel is poured in trumpet and it will pass
the liquid to the other mould with the help of piping of refractory in plate on
which all mould are placed. The casting powder are hanged in mould. Cover
powder and anti-cover powder use to fill cavity because when metal solidify some
empty remaining then the powder are exothermic burn and produce heat and
cavity is filled. The mould are made up of cast iron. Some of high alloy and stain
less steel are used to prepare.

30
I.C Moulds:
SHAPE CAPACITY (ton) PRODUCT WEIGHT (kg)ROUND
R-13 11500
R-8 7900
R-7 6400
R-5 4700
R-3 2600
R-2 2100
R-0.6 630
OCTAGON
Oct-12 12000
Oct-8 7600
Oct-5 4700
Oct-3 2900
Oct-2 2100
Oct-0.25 250
Kg
SQUARE
SQ-1250 1200
SQ-700 680
FLAT
FL-1600 1650
FL-1200 1350
FL-1000 1000
FL-600 600

31
ROLE OF REFRACTORY IN PSM:
1. What is Refractory?
Refractories are ceramic materials designed to withstand the very high
temperatures (in excess of 1,000°F [538°C]) encountered in modern
manufacturing. More heat-resistant than metals, they are used to line the hot
surfaces found inside many industrial processes. In addition to being resistant to
thermal stress and other physical phenomena induced by heat, refractories can
withstand physical wear and corrosion caused by chemical agents.
Refractories are inorganic, nonmetallic, porous and heterogeneous materials
composed of thermally stable mineral aggregates, a binder phase and additives.
The principal raw materials used in the production of refractories are normally
the oxides of silicon, aluminum, magnesium, calcium and zirconium. There are
some non-oxide refractories like carbides, nitrides, borides, silicates and
graphite.
1. Acidic Refractory:
Acid refractories are those which are attacked by basic slags. These are not
affected by acid slags and hence, can be safely used where the environment
is acidic. Examples of acid refractories are:
1. Silica (Most acidic)
2. Semi - Silica
3. Alumino - Silicate Refractories.
High Alumina (exception, for they react with basic slags)
Fireclay groups e.g. LHD (Low Heat Duty), HHD (High Heat Duty), SD
(Super Duty), High Grog
Kyanite, Sillimanite, Andalusite.
Here in case of Fireclay bricks one thing to be kept in mind is that the
higher the percentage of Al2O3 the higher is the fusion point & greater is
the resistance to basic slags.
2. Basic Refractory:
Basic refractories are those which are attacked by acid slags. Since they do
not react with basic slags so, these refractories are of considerable
importance for furnace linings where the environment is basic for

32
example, in furnace for non-ferrous metallurgical operations. Examples
of basic refractories are: Magnesite, Mag-Chrome, Chrome-Mag,
Dolomite, Forsterite.
3. Neutral Refractory:
These are the refractories that are neither attacked by acid nor by basis
slags. Examples are:
 Graphite (Most inert)
 Chromites
 Artificial refractories like - Zirconium Carbide, Silicon Carbide
(depending on the amount of oxidation & type of bond in the
material, it reacts with basic slags to form an acid refractory).
Out of these Graphite is the least reactive and is extensively used in
metallurgical furnaces where the process of oxidation can be controlled.
2. REFRACTORY DEVELOPMENT CENTRE:
I. Magnesia Carbon Bricks:
Magnesia carbon brick series used for the electric furnace are made by
adoption of fused magnetite, high-purity
magnesium sand and graphite as
principal raw material, through high-
pressure molding and low-temperature
treatment. This product is mainly used
for electric furnace lining, which enjoys
advantages including high temperature
resistance strength, corrosion and
spalling resistance. According to the
smelting conditions and the kind of
smelting steel, different brands magnesia carbon bricks are available.
Magnesia-carbon bricks are resin bonded bricks containing high-purity
fused and or sintered magnesia and flake graphite as their main
ingredients. Magnesia Carbon Brick has excellent corrosion resistance

33
together with good thermal shock properties. It offers good oxidation
resistance due to use of high purity flake graphite.
Magnesia Carbon brick in PSM is totally imported. In RDC only High
Alumina Brick is manufacture.
II. High Alumina Bricks:
High alumina bricks are refractory materials used in the linings of various
kilns, stoves and furnaces for cement, metallurgy, power and
petrochemical industry. It is a kind of neutral refractory, quality bauxite as
the main raw material. The main composition of the brick is Al2O3, which
is up to more than 48%. A high alumina brick can withstand high
temperature and thermal shock, has a low thermal conductivity and a
stable bulk size.
Due to its excellent features and properties,
high alumina bricks are usually used in
building blast furnaces, reverberator
furnace, electric arc furnaces, rotary kiln,
hot air stoves, converters, melting furnace,
heating furnaces, soaking furnaces, and
heat treatment furnace, etc.
This kind of bricks has an excellent
performance under extreme temperature, it
has the refractoriness of up to 1770℃. The
refractoriness provides the product a fine
quality to be used as furnace and kiln linings.
High Alumina Bricks is made by mixing of following components;
Flint Clay
Shmot (70%)
Plastic Clay
Magnesite Powder
Sagar 71 Cement
After mixing this component, mixture is again mix with green mortar
(Acidic Binder) in Mixer. The yield product is High Alumina and its brick
is made in Screw friction press with pressure of 250 ton. The size of brick
is standard (75x230).

34
III. Insulation Bricks:
Insulation Brick is a class of brick, which consists of highly porous fireclay
or kaolin. Insulation Bricks are lightweight, low in thermal conductivity,
and yet sufficiently resistant to temperature to be used successfully on the
hot side of the furnace wall, thus permitting thin walls of low thermal
conductivity and low heat content. The low
heat content is particularly important in
saving fuel and time on heating up, allows
rapid changes in temperature to be made,
and permits rapid cooling. Insulation Brick
is characterized by the presence of large
amount of porosity in it. The pores are
mostly closed pores. The presence of
porosity decreases the thermal conductivity
of the insulating bricks.
Following process machinery were observed in RDC.
 Rotary Kiln
 Crusher
 Grinder
 Ball Mill
 Mixer
 Screw Friction Press
IV. Electric Arc Furnace Refractory Lining:
Bottom:
o Magnesia Carbon Bricks
Inside:
o Magnesite Mass Pasting
 Gunning Powder
 Thickness 1-15”
o Magnesia Carbon Bricks
 11-lines
V. Ladle Refractory Lining:
Shell
o Thickness: 16-30 mm

35
o Mild Steel
Micro Theum
o Heat Proof (5-7 mm)
Insulation Tile
o 32 mm
Safety Lining
o Alumina Tile
o Magnesite Tile
o Magnesite Chrome Tile
Working Line
o Slag Zone
 Magnesia Carbon Brick
o Metal Zone
 Magnesia Carbon
 Dolomite
 Magnesia Chrome
VI. Tundish Refractory Lining:
Shell
o Mold Steel
Insulation Brick
o Silica Base
High Alumina Brick
Mortar
o Alumina Base
o Tundish Gunning Mix
R-SHOP (Forging):
Forging: (R-1)
Forging is a manufacturing process that results in the shaping of metal by using
calculated force. Forging is executed with a power hammer or a die during the
shaping process to produce the intended design of the forged metal object.
Forging also has multiple classifications, identified according to the temperature
at which the forging process is being performed. This includes cold forging or hot
forging, each offering its own distinct advantages. Forged parts could range in
size from less than a kilogram to hundreds of metric tons and be customized to
fit any shape or size desired.

36
Open Die Forging
Open die forging is the process of deforming a piece of metal between multiple
dies that do not completely enclose the material. The metal is altered as the dies
“hammer” or “stamp” the material through a series of movements until the
desired shape is achieved. Products formed through open forging often need
secondary machining and refining to achieve the tolerances required for the
finished specifications. Open die forging is widely used for the products in small
quantity that are simple, rather than complex, such as discs, rings, sleeves,
cylinders and shafts. Custom shapes can also be produced with open die forging.
The strength of the grain structure will be increased during the deformation
process due to the repeated working of the steel billet. Another benefit of open
die forging is that the fatigue resistance and strength of products will be
improved. Besides, voids could be effectively reduced after open die forging.
Closed Die Forging:
Closed die forging (also known as an impression die forging) is a metal
forming process that compress a piece of metal under high pressure to fill an
enclosed die impression. For some special shapes, second forging operation is
required to reach final shapes and dimensions. The type of material, tightness of
tolerances, and need for heat treatment can determine the cost of a closed die
forged part.
Machinery:
Machinery Capacity / Pressure Quantity
Reheating
Furnace
50 kg 1
100 kg 4
200 kg 5
400 kg 1
Free Forging Hammer
½ ton 2
1 ton 1
Drop Forging Hammer ½ ton 2
Die Forging Hammer 3.15 1
Counter Flow Hammer 6 ton 1
Band Saw Machine - 1

37
Input:
 Round Bars (D38-66mm)
 Flat Bars
 Square Bars
Output:
 Round Bars (12-50 mm)
 Square (12-50 mm)
 Rectangle
 Hexagonal
 Hollow sleeves
 Gear Blank
 Dummy Bars
 Crown Wheel
 Chisel
Press Forging (R-3):
Press forging may be defined as the process of shaping a metal that is placed
between two dies by applying mechanical or hydraulic pressure. Press forging is
usually done on a forge press - a machine that applies gradual pressure on the
forging dies. The shape of the metal is usually accomplished by a single stroke of
the press for each die station.
 Deforms the work piece completely
 Compression rate of the work piece can be controlled
 More economical for high volume productions
 Any size and shape can be created
 Requires less draft and produces lesser scrap.
Input:
 SQ-700
 SQ-1250
 OCT-8000
 OCT-5000
 OCT-3000
 ESR-400-600-800-1000-1250
Output:
 Round Bar (200-500 mm)
 Square Block/Bar (450 mm)

38
 Rectangular Bars (150-400 mm)
 Disk (200 mm)
 Ring (1500-2000 mm)
 Rectangular Block
Machinery:
Machinery
Capacity / PressureReheating
Furnace 2 MT
4 MT
10 MT
40 MT
Hydraulic Press
(Water + Air) Based
1700 ton
Rail Bonded Manipulator 15 ton
Rotary Trolley
Top Hat Electrical
Furnace
1.5 ton
LONG FORGING MACHINE (P-1)
The perfect equipment to provide excellent quality and flexibility in shapes and
sizes for the production of super alloys.
Characteristic:
 Radial Direction
o Forging from all direction.
 Forging Defects:
 Crack
 Seam
 Chips
 Folding
 Computer Numerical Control
 Program Logic Control

39
 2- Manipulator
o Check Head-A
o Check Head-B
 Pressure 400 tons
o Normally use 200-250 ton
 Reduction Passes 30mm
Input:
 Oct-230
 Bloom-230
 Round-230
Output:
 D50
 SQ50
 FL (30-50)
 OCT-230-50
 Maximum Length of Product
o 6m
Machinery:
Walking Beam
o Reheating Furnace
o Steps of Walking
o 60 ton per hour
o Gas Fired
o 3-Zones
 Zone-1: 8000
C
 Zone-2: 9500
C
 Zone-3: 11500
Cs
Austrian Made Furnace
o Heat Treatment Furnace
 Annealing, Normalizing, Hardening, Tempering
o Capacity 15 MT
o 3-Zones
o Boggy Type
o Gas Fired
o 14 Burners
o Temperature Variation (±20
C)
o PLC Control

40
Chinese Made Furnace
o Heat Treatment Furnace
 Annealing, Normalizing, Hardening, Tempering
o Capacity 10 MT
o Boggy Type
o Gas Fired
o 6 Burners
o 3-Zones
o PLC Control
o Temperature Variation (±200
C)
Straightening Machine
Peeling Machine
Q-SHOP (Bar-Rolling)
Roughing Mill/ Hot Rolling Mill:
Rolling process is one of the most important and widely used industrial metal
forming operations. It provides high production and close control of the final
product. Shapes are processed by hot rolling by passing them through plain or
grooved cylindrical rotating rolls to produce plates, sheets, rods, structural
sections, and tubes etc. It accounts for 90 % of all metals produced by metal
working processes. Rolling of steel is a metal forming process in which steel is
passed through a pair of rotating rolls for plastic deformation of the steel. Plastic
deformation is caused by the compressive forces applied through the rotating
rolls. High compressive stresses are as a result of the friction between the rolls
and the steel stock surface. The steel material gets squeezed between the pair of
rolls, as a result of which the thickness gets reduced and the length gets
increased. Rolling is classified according to the temperature of the steel rolled. If
the temperature of the steel is above its recrystallization temperature, then the
process is termed as hot rolling. If the temperature of the steel is below its
recrystallization temperature, the process is termed as cold rolling. Three rolls
are rotating. Rotation of center roll is anticlockwise and others are clockwise. The
Rolls are 3HI-Non Reversing. Input is got from M-Shop usually. There are Guide
Box are installed in Mill Bar for accurate passing. 750 KW motor is functions for
rotating bars with 90 RPM. Product is Round Bar, Flat and Deform shape with
help of input only billet or bloom.
Finishing Mill:
The function of finishing mill is same as roughing mill. Its only increase length
according to requirement and make finished product. There are 4 finishing mill
are equipped in Q-shop. For a particular shape and length, then it is cut down in
Shearing Machine. After cutting in length it is the product is taken for MPI Test.

41
MPI Test: Magnetic Particle Inspection Test for checking out defects such as
Cracks, Folding, Seam, Roughness etc and these are removing by grinding.
MPI Test is taken in a way that bundle of bars are placed on electrical
conductivity frame and electricity is passed through and MPI ink is spray on it
and cracks are easily available.
N-SHOP (Rolling):
Rolling:
The material is heated in reheating furnace then processed in 2HI-Reversing
Rolling Mill which increase the length of bar by decreasing the thickness. After
that a Shear Machine is placed at right after rolling mill for cutting pieces into
desire length. For leveling cut piece is passed through leveler.
2HI-Reversing
o Motor : 1000 KW
2-Roller
o Rotating in opposite direction with each other.
Max. RPM: 80 RPM
Current Load: 400 A
Hot Rolling
Reheating Furnace
o Capacity 9 ton/hr
o Fuel and Air mixture
 Natural Gas (1:10)
o 3-Zones
 Top
 Bottom
 Soaking
Crystallization Heat Temperature
o Greater
 Hot Roller
o Below
 Cold Rolling
Input:
 Slab
 Bloom
o 230
 Billet
 Square Ingot

42
Output:
 Flatting
 Round Bar / Billet
o 90,130
 Gothic Bar
o 76x76
 Bloom
o SQ: 200-230
Peeling Bay:
1. Slab Grinder
o Fixed Machine
o Input
 Flat Ingot, Round ingot, Octagonal
o Defects Remover
 Crack
 Folding
 Seam
o Casting/rolling/forging defects renovation
2. Billet Grinder
o Movable
o Input
 Octagonal, Square, Billet
 100-180
 Bloom 230
3. Hand Grinder:
o Round Bar, Flat
o Tolerance Control
WATER TREATMENT PLANT:
Water Treatment:
Water treatment is any process that improves the quality of water to make it
more acceptable for a specific end-use. The end use may be drinking, industrial
water supply, water recreation or many other uses, including being safely
returned to the environment. Water treatment removes contaminants and
undesirable components, or reduces their concentration so that the water
becomes fit for its desired end-use.

43
Chemical Treated Water Supply:
Electric Arc Furnace 1 & 2
o 3-Heat Exchanger
 Plate Type, Tube Type
o 2-Cooling Tower
o 6- Compressors
 Continuous
Ladle Furnace 1 & 2
Vacuum Degassing
Vacuum Oxygen Degassing
Boiler
CC
o Primary Cooling
o Secondary Cooling
 Done by Fresh Water
 Untreated Water
 Also For Transformer Oil Cooling
Treatment
o Fresh Water
 Filter
 Softening
 2-Softerner
 A & B
 Done by Sodium Zeolite Bed
o Removing of Hardness
 Ca & Mg
o Back Wash after treatment
 Recovery of NaZ Bed
 Brine Tank
 Rock Salt
 Ammonia Buffer
 Reagent
 Eriochrome Black T
 Chemical Addition
 Corroshield NT4209
o Corrosion Protection
o 3 liters on 1000 liters
 Test for Treatment

44
 PH
 Iron
o Removing of Iron
 Nitrate Test
o Minimum (500-800 ppm)
 Hardness
o Titration Method
Quality Assurance Department (QAD)
1. Workshop:
Sample Handling
o From EAF 1 & 2, LF 1 & 2, VD/VOD, CC & IC
o Cooled down by water
o Grinding
 Circulator Centre Grinder Machine
 Polishing
Machines
o Lathe Machine
o Drill Machine
o Grinding Machine
2. Optical Emission Spectrometer
Optical emission spectrometry involves applying electrical energy in
the form of spark generated between an electrode and a metal sample,
whereby the vaporized
atoms are brought to a high
energy state within a so-
called “discharge plasma”.
These excited atoms and
ions in the discharge plasma
create a unique emission
spectrum specific to each
element, as shown at right.
Thus, a single element
generates numerous
characteristic emission
spectral lines. Therefore,
the light generated by the
discharge can be said to be a collection of the spectral lines generated

45
by the elements in the sample. This light is split by a diffraction
grating to extract the emission spectrum for the target elements. The
intensity of each emission spectrum depends on the concentration of
the element in the sample. Detectors (photomultiplier tubes) measure
the presence or absence or presence of the spectrum extracted for each
element and the intensity of the
spectrum to perform qualitative
and quantitative analysis of the
elements. In the broader sense,
optical emission spectrometry
includes ICP optical emission
spectrometry, which uses an
inductively coupled plasma
(ICP) as the excitation source.
The terms "optical emission
spectrometry" and
"photoelectric optical emission spectrometry," however, generally refer
to optical emission spectrometry using spark discharge, direct-current
arc discharge, or glow discharge for generating the excitation discharge.
Shimadzu optical emission spectrometers feature Pulse Distribution
Analysis (PDA) to enhance the measurement reproducibility (accuracy).
This method involves statistical processing of the spark pulse-generated
emission spectra obtained from spark discharges in an argon
atmosphere. The optical emission spectrometer offers rapid elemental
analysis of solid metal samples, making it indispensable for quality
control in steel making and aluminum metallurgy processes.
Metal Testing
No Oxides Testing
Only polished piece
Table Stand
o Sample Hold
o Electrode
 Tungsten
 High Energy Emission
 Photon (Energy)
o Spark
 2-3 times
 Average taken
Within one minute
o All composition got

46
Followed by According to Specification
Detection in Optics
o Greeting
UV visible
22 Elements: 22 Focus: 22 Separator
3. XRF-Spectrometer
ED-XRF Spectrometer, X-Ray Fluorescence, X-Ray Fluorescence Analysis
X-Ray fluorescence analysis
using ED-XRF spectrometers
is a commonly used
technique for the
identification and
quantification of elements in
a substance. SPECTRO`s
stationary ED-XRF
spectrometers are based on
the energy-dispersive-X-ray-
fluorescence analysis
method. The atoms in the
sample material, which could
be any solid, powder or
liquid are excited by X-Rays
emitted from an X-Ray tube
or radioisotope. For increasing sensitivity, the primary excitation radiation can
be polarized by using specific targets between the X-Ray tube and the sample
(ED-P (polarization)-XRF). All element specific X-Ray fluorescence signals
emitted by the atoms after the photoelectric ionization are measured
simultaneously in a fixed mounted semi-conductor detector or sealed gas-
proportional counter.
The radiation intensity of each element signal, which is proportional to the
concentration of the element in the sample, is recalculated internally from a
stored set of calibration curves and can be shown directly in concentration
units.
Wavelength obtained by Bragg’s Equation
o nλ = 2 d sin θ
Phenomenon
o X-ray Phenomenon
 Generation

47
o Emission on Sample
 Sample Generate Secondary X-ray
 Unique Wavelength
3. Wet Chemical Analysis:
Chemical Analysis
o Chemical composition metal, alloys and non-metals.
o Raw Material
 Ferroalloy
 Ferrosilicon, Ferromanganese, Ferrochrome,
Ferrovanadium
 Analyzer
o Si-Mn-P-Cr-Ni-Ti-W etc
 Ferrous
 Cast Iron-Pig Iron- High Carbon Steel- Low Carbon
Steel- Medium Carbon-Stainless Steel- Tool Steel-
 Non-Ferrous
 Brass-Bronze-Tin
 Ingredients: Cr-Pb-Sn-Al-Fe-Cd-C-Ca
 Refractory
 Fire Clay- Dolomite-Fluorspar-Chrome Manganese
 Ingredients
o SiO2- Al2O3-CaO-P2O5- MnO-ZrO2-MgO2
o Standards
 ASTM
 Mostly
 British
 ISO
 Japanese
 Chinese
Water Analysis
o Total Hardness
o PH
o TDS
Instruments
o 2-Oven Dryer
o PH
meter
o Shaker Balance
o Run Operator
o Muffer Furnace

48
 Max. Temperature 11000
C
o Bulk Density Operator
o Spectro photo meter
 U.V Spectroscopy
 Lower Range (0.1-2 ppm)
 Si, Mn, Cr, Ni, P analyze
4. Mechanical Analysis
Test
o Hardness
o Ultimate Tensile Test
o Toughness
o Ductility
o Compressive
1. Hardness
o Brittle Harness Test
 Tungsten Carbide ball use in Intender
 Force 3000 kg
 We use brinell when sample width double the sheet
 We hold 10-15 sec to resist elasticity
o Rockwell Hardness Test
 Start minor force then HRB-100 kg-HRC-150 kg force
 HRB-ball intender use, HRC diamond cone intender use
 Size limitation in brinell we use Rockwell because in brinell thin sample
test.
2. Universal Tensile Machine
A Universal Testing Machine (UTM) is used to test both
the tensile and compressive strength of materials.
Universal Testing Machines are named as such because
they can perform many different varieties of tests on an
equally diverse range of materials, components, and
structures. Most UTM models are modular, and can be
adapted to fit the customer’s needs.
Universal Testing Machines can accommodate many
kinds of materials, ranging from hard samples, such as
metals and concrete, to flexible samples, such as rubber
and textiles. This diversity makes the Universal Testing
Machine equally applicable to virtually any
manufacturing industry.
The UTM is a versatile and valuable piece of testing
equipment that can evaluate materials properties such as
tensile strength, elasticity, compression, yield strength,
elastic and plastic deformation, bend compression, and strain hardening. Different models of

49
Universal Testing Machines have different load capacities, some as low as 5kN and others as
high as 2,000kN.
Tests can also be performed in controlled environmental conditions. This is achieved by
placing the Universal Testing Machine into an environmental room or chamber. For example,
metals testing can be conducted at extreme temperatures: from -196°C (-321°F) to over 1000°C
(1800°F).
5. Metallography:
Metallography is the study of the microstructure of all types of metallic alloys.
It can be more precisely defined as the scientific discipline of observing and
determining the chemical and atomic structure and spatial distribution of the
constituents, inclusions or phases in metallic alloys. By extension, these same
principles can be applied to the characterization of any material.
A. Sampling:
Cut the sample through micro cutting machine.
B. Mounting:
Mounting through mounting machine using plastic material like Bakelite
mounting machine temperature max 180-2000
C. Mounting machine
pressure 150 kg.
C. Grinding:
Grinding through rough and fine grinding paper, grinding starts with
rough paper then grade of grinding paper increase unless the surface
becomes flat.
D. Polishing:
After grinding specimen is polished clothes and mirror like surface is
obtained.
E. Etching:
The purpose of etching is to make visible the many structural
characteristics of the metal or alloy. The selection of appropriate etching
reagent is determined by the metal or alloy and specific structure desired
for viewing.

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