Cast iron its types , properties and its applications....
In-Plant Training Report Presentation
1. Roll No: 08085707
Registration No: 1834
Session: 2007-08
Department of Materials Science &
Engineering
Rajshahi University
2. BISCO PLANT
We have visited the BISCO (BSRM Iron & Steel Co. Ltd.) plant,
the mother-plant of BSRM where the production process of
billets consist of mainly 3 section.
Those are –
• IF (Induction Furnace) section
• LRF (Ladle refining furnace) Section
• CCM (Continuous Casting Machine) Section
They produce two types of billet
Grade 40 (500CWR)
• Grade 60 (420DWR)
Name C Si Mn P S
Grade 60 0.31-0.36 0.31-0.36 1.1-1.4 0.5 <0.5
Grade 40 0.18-0.24 0.18-0.24 0.75-0.90 0.5 <0.5
3. SCRAP
• Old cars and machines or pieces of metal, etc.
that are not now needed but have parts that can
be used to make other things.
• BSRM uses four types of scrap-
1.Sheredded
2.HMS
3.Bundle
4.DRI
4. One of the most common forms of
wrought iron and steel scrap, heavy
melting steel (HMS) is recyclable
steel derived from a variety of
sources—for example, railroad
wheels, ship plates, construction
scrap, auto and truck bodies.
Shredded scrap steel is recyclable
steel mainly extracted from obsolete
automobile parts through the use of
magnets, then “shredded”, i.e., cut
into smaller, manageable pieces.
Shredded
HMS
Shredded
HMS
5. Direct-reduced iron (DRI), also called
sponge iron, is produced from direct
reduction of iron ore (in the form of
lumps, pellets or fines) by a reducing
gas produced from natural gas or coal.
Bundle
Sponge iron
Bundle scrap is usually consists of long
filament of recyclable scrap. It is
collected from different types of tin
container.
Bundle/Fresh like
DRI
6. Weight percentage of carbon in different scrap
Sheredded = 0.5-0.6%
HMS = 0.15-0.21%
Bundle = 0.03-0.04%
DRI = 0.1%
Ferrous alloys are also poured into the furnace to create
the quality. There are three types of ferrous alloys are
used in the melt-
Ferro Manganese (FeMn)
Ferro Silicon (FeSi)
Silicon Manganese (SiMn)
7. INDUCTION FURNACE PREPARATION
The coil is first bound by silica tape.
Mica block is inserted between two
coils.
Mica block and coil bound by glass
tape again .
For acidic lining they use ramming
mass between the forma and coil.
For binding the ramming mass with
the coil they use grouting cement.
Sintering the furnace at temperature
1417°C for 8 hour’s. Coil of Induction Furnace
8. Ramming mass
98.7% SiO2 + 1.3% H3BO3
250 kg Silica + 5 kg Boric Acid
Sidewall = 5.6 tons
Bottom = 1.5 tons
Top Cap
NaSiO3 = 1.2 tons
Water = 200 Litres
SiO2 = Balance
Grouting Cement
Al2O3 = 82-87%
CaO = 5.8-6.8%
Fe2O3 = 1-1.7%
9. INDUCTION FURNACE
After sintering the furnace is
looks as like the figure. The
furnace is fully prepared for
scrap melting.
Induction furnace
10. FURNACE REPAIRING
Three types repairing
1.Hot Patching
2.Patching
3.Full lining
1.Hot Patching
• After 4/5 heats
• Lining not broken
• Bottom not broken
2.Patching
• After 15/17 heats
• Lining broken
• Bottom broken
3.Full lining
• After 15/16 patching ( 225 heats)
• Coil repair
11. LADLE REFINING FURNACE
Ladle Refining Furnaces are a
proven technology used for
producing alloy-steel, de-
sulpharizing, de-oxidizing liquid
steel and for improving the
productivity from a steel plant.
Ladle Refining is a post-melting
treatment that is after melting in
either the Induction Melting
Furnace or Electric Arc Furnace
Ladle Refining Furnace
Argon
Graphite Electrodes
LRF
12. Ladle Preparation
In ladle lining there are two zones
• Metal zone (11 layer)
• Slag zone (12 layer)
Alumina brick is used in metal Zone. Carbon black brick is used in slag zone
Ladle
Metal ZoneAlumina Brick Carbon Black Brick
13. Operation procedure
1. Raise and keep molten steel temperature. The molten steel heated
by arc to get new thermal energy. Graphite electrode use for arcing.
2. Lime (CaO) , CaF2 addition for slag making.
3. Pet coke, Met coke,CaC2, CaSi2-wire, FeMn, SiMn, FeSi etc are
using for chemical adjustment.
4. Average process time (30-40 ) min.
5. Average arcing time (20-25) min.
6. Temp checking average (2-3) times.
7. Average 1st temp. at LRF (1585-1590) degree centigrade.
8. Average lifting temperature (1600-1605) degree centigrade.
9. Nitrogen/ Argon purging on whole process time for stirring of the
molten metal promote homogenization.(After 20minutes using of
Argon should be start in case of purging)
15. CCM SECTION
There are two steps involved in transferring liquid steel from
the ladle to the molds. First, the steel must be transferred
(or teemed) from the ladle to the tundish. Next, the steel is
transferred from the tundish to the molds.
16. A severing unit (cutting torch or mechanical shears) to cut
the solidified strand into pieces for removal and further
processing.
17. Finally the billet is come into the billet section. Every
billet is cutting down at a length of 12m and the cross
sectional area is 160mm × 160mm.
19. NEW PRODUCT OF BSRM
BSRM Xtreme
BSRM Xtreme rebar’s are hot-
rolled from prime quality steel
billets and subjected to on-line
thermo-mechanical treatment in
three successive stages.
1.Quenching
2. Self Tempering
3. Atmospheric cooling
