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CONTENTS
Introduction
Steel Melting Shop
Vacuum Arc Degassing
Vacuum Oxygen Decarburization
Ladle Furnace
Argon Oxygen Decarburization
Continuous Casting Shop
Blooming and Billet Mill
Forge Shop
Plate Mill
Heat Treatment & Finishing Shop
Conditioning Shop
Mechanical Repair Shop
Boiler House
Conclusion
Steel Melting Shop
The basic function of SMS is to produce hot metal from Ferro scrap
and providing input material to ingot mould and caster for taking a
shape. Slag is also an output of SMS which are used by cement
industries for cement making.
Basic highlights of SMS:
Electric Arc Furnace (EAF)
Transformer rating of this furnace is 25 MVA for stainless steel
furnace and 18.75 MVA for the non stainless steel furnace.
One heat requires 3 hours to complete.
After tapping the molten metal is sent to VOD/VAD/LD directly.
In VAD the molten metal is degassed to removed the Hydrogen or
Oxygen from the metal to reduce their amount to an acceptable
ppm level.
VAD Furnace Ladle Furnace
VOD Furnace AOD Furnace
CONTINUOUS CASTING SHOP(CCS)
Through continuous casting route mainly stailess steel slabs are
produced. In ASP there was a twin caster i.e. slab cum bloom caster
which culd be used either as single strand slab caster or double strand
bloom caster in operation.
For continuous casting there is mould where the liquid metal is to be
poured.Before the ladle comes inside the mould some biscuit and
chocolate size bar is placed to give the shape of the slab.
Casting can be sequential or in batch . In sequential casting 2 or more
then 2 ladles are brought to turret for casting one by one.But in batch
only one ladle is cast.
BLOOMING AND BILLET MILL (BBM)
In ASP, Blooming & Billet Mill plays a major role. Here the
primary rolling mill is use to compress the soaking pits. In this process
the soaking pit is use at temperature 1180-1800 C.
BBM consists of Blooming Mill, Billet Mill & Soaking pits. This
mill produces blooms, billets, squares, rounds, & slabs of various sizes
& can handle all grades of alloy steel produced at SMS. At 1 st in pit
furnace a metal shape is heated and then it passed between two rollers.
In roller operation the crossection of the specimen is gradually
decreased.
CONDITIONING SHOP
COOLING LUD
HOT SAW
BILLET SHEAR
650 mm BILLET MILL 2
700 mm BILLET MILL 1
BLOOM SHEAR
LD SCARFING MACHINE
900 mm TWO HIGH REVERSING MILL
SOAKING PIT FURNACE
FROM SMS & CCS
MAJOR CONTROLLERS IN B.B.M.:
Pit temperature controller.
Fuel controller.
BLOOMING & BILLET MILL
FORGE SHOP
The forge shops have two type of forging presses for producing
compact steel forgings. One is computerized forging press & another
one is manual forging press which have 2 T capacity.
In forging shop there is two heating chamber for heating the
material before forging process. 1st chamber is use for gradually
increasing the temperature of the specimen. Here the specimen doesn’t
reaches the particular temperature which is not suitable for the forging.
And the 2nd chamber is use for reheating the specimen. The total
heating time is 6hrs. After that the specimen is ready for the forging.
USE OF FORGING:
It is use for making a specimen of required shape. By the forging
press we get a final product of good surface finish. In forging process
rectangular shape can be change in circular shape & also vice-versa.
After processing in this shop the material is then sent to Heat Treatment
and Finishing shop.
SECTION:
Press Bay
Hammer Bay
INPUT MATERIAL:
Blooms of various sizes.
CONTROLLING PARAMETERS OF FURNACE:
Metal temperature.
Fuel flow.
Combustion flow.
Compressed air flow.
Furnace pressure.
PRODUCTS:
Rounds, squares, die block, flats, rings etc.
Diagram of Forging Press machine
Forging Hammer Reheating Furnace
Forging Pressure Forging Roll
PLATE MILL
The ingots are rolled at Blooming and Billet Mill for producing blooms, billets,
rounds and slabs in a variety of steel grades & sizes. The rolled slabs are further
rolled in Plate mill to produce plates. Today thermomechanical rolling is the
most important production process for the manufacture of high strength plates.
In this method the temperatures are exactly set for finish rolling and for cooling.
CONDITIONING SHOP
Detection and removal of surface defects like cracks and making
materials ready for further processing a/c to customer’s needs.In
the conditioning shop, the surface defect of the products are
removed prior to shipping further rolling or forging in order to
meet the required quality standard of the finished product. The
further processing is known as conditioning. This shop is equipped
with slow cooling boxes and bogie.Hearth type dispositioning
furnaces for treatment of products received from BBM.Other
facilities include straightening machines,saw and flame cutting
machines elaborate inspection and testing arrangements for spark
and spectro testing for quality control.
INPUT MATERIALS :
Products from-
Forge shop
BBM
Bar mill
There are two types of conditioning shops:
1.CONDITIONING SHOP 1
Normal cooling Box cooling Grinding
Cutting Furnace cooling
2.CONDITIONING SHOP 2:
In this shop materials come from continuous casting shop.
HEAT TREATMENT AND FINISHING SHOP
Here different types of heat treatment arrangements such as for oil
quenching, water quenching are present in order to impart specific
properties to the alloy steel as per customer’s requirement.
BOILER HOUSE
This unit provides steam for the entire plant. Steam is used
in vaccuam creation system consisting of converging and
diverging nozzles. The water to be sent to boiler is first
demineralised by passing it through cation exchanger and
anion exchanger. This is done to prevent scaling by
deposition of minerals on inner surface of boiler which
reduces the life of boiler considerably. The water sent to the
boiler is checked regularly in a chemical laboratory.
MECHANICAL REPAIR SHOP(MRS)
This is the Mechanical repairing shop which is support the
production of the plant as well as looking after breakdown and
preventive maintenance of equipment.
It has Four Sections. Eg; i) Overhauling & Fitting, ii) Winding ,
iii) Testing & iv) Preventive & Breakdown Maintenance.
* Overhauling & Fitting Section :
This section repairs the motor, generator etc, after careful
inspection of all parts & repair it accordingly.
* Welding Section : -
Welding of AC Motor of both Squirrel Cage & Slip Ring upto the
capacity of 225 KW, 415V. 1480 RPM can be done.
* Testing Section :
At Testing section all DC & AC Motors upto the capacity of 100
KW can be Tested.
* Preventive & Breakdown Maintenance : -
Maintains Lathe, Drill, Planning, Copy planning , Welding
etc, for uninterrupted production & to ensure equipment
availability.