merchant mill @ dsp

1. STEEL AUTHORITY OF INDIA LIMITED
PRESENTATION OF VOCATIONAL TRAINING AT
DURGAPUR STEEL PLANT
DURATION : 19TH MAY 2014 - - 1ST JUNE 2014
BY
SONU DAS
11/MME /30
DEPARTMENT OF METALLURGICAL AND MATERIALS
ENGINEERING
NATIONAL INSTITUTE OF TECHNOLOGY,DURGAPUR

2. About Durgapur steel plant
 Set up in late 50’s.
 Initial annual capacity of 1 million tons of crude steel per year, the capacity of Durgapur Steel
plant (DSP) was later expanded to 1.6 million tons in the 70's.
 Massive modernization program was undertaken in the plant in early 90's, which, while
bringing numerous technological developments in the plant.
 Enhanced the capacity of the plant to 2.088 million tons of hot metal.
 1.8 million tons crude steel .
 1.586 million tons saleable steel.
 The entire plant is covered under ISO 9001: 2000 quality management system.
 DSP’s Steel Making complex and the entire mills zone, comprising its Blooming & Billet Mill,
Merchant Mill, Skelp Mill, Section Mill and Wheel & Axle Plant, are covered under ISO: 9002
quality assurance certification.
 Plant covering an area 6.4 km.
 It is situated at a distance of 158 km from Calcutta, It is situated on the banks of the Damodar
river. The Grand Trunk Road NH-2 and the main Calcutta-Delhi railway line pass through
Durgapur.

3. Products :
PRODUCT-MIX TONNES/ANNUM
Merchant Products 2,80,000
Structural 2,07,000
Skelp 1,80,000
Wheels & Axles 58000
Semis 8,61,000
Total Saleable steel 15,86,000

4. Flow chart of Durgapur Steel Plant

5. Operational Departments
 1.Raw material handling plant
 2.Coke ovens
 3.Sinter plant
 4.Lime calcination plant
 5.Oxygen plant
 6.Blast furnace (4 nos. out of which 3 is in working condition)
 (Gross capacity of 2.088million tonne/annum).
 7.Steel melting shop
 7.1 )BOF shop with 3 converter capacity 110 tonne each ladle.
 7.2)Continuous casting plant(capacity .773 million tonne/annum).
 8.Blooming mill (capacity .950 million tonne/annum).
 9.Billet mill(capacity .957 million tonne/annum , continuous Morgan design).
 10.Section mill(capacity .212 million tonne/annum).
 11.Skelp mill(capacity .25 million tonne/annum).
 12.Merchant mill (capacity .28 million tonne/annum , continuous Morgan design
with 4 Repeaters ).
 13.Wheel and axle plant(capacity 58000 tonne/annum).

6. MERCHANT MILL
The Merchant Mill produces plain round and Thermo-Mechanically Treated (TMT)
bars in the range of 16mm - 28mm. The entire product range of TMT bars and rods
at DSP is branded .
Capacity - 0.28 million tonnes / year
Type of mill - continuous Morgan design
Horizontal stands - 13, Repeaters - 4
Product range :
Plain rounds - 12 - 32 mm dia
TMT bars - 12 - 25 mm dia

7. TMT : TMT means Thermo mechanically treated steel its a new-generation-
high-strength steel having superior properties such
as weld-ability, strength, ductility and bend-ability meeting
highest quality standards.
Steel bars get intensive cooling immediately after rolling to
make the surface layer hard.
The internal core is hot at the same time.
Due to further cooling in atmosphere and heat from the core,
the tempering takes place.
Improved properties such as yield strength, ductility and
toughness and corrosion resistance with above properties,
TMT steel is highly economical and safe for use.

8.  To produce the rods having size (15-28)mm Dia .
 Input material (100*100)mm and 9 meter long slab
usually come from Bloom and Billet mills & from CCP.
Capacity 70 tons,
Temp. ~1100-1200 c
By pusher
slab
Reheating
chamber
Coke oven
gas +Bf gas
mixture
Series of 14
roller
Thermax
furnace +
water
quenching
TMT
Bar
Inspection
Inspection of
mechanical properties
Zone 1
Side charging
Zone 2
Reheated slab
discharging
Stand no 3,4,5 drive 400HP DC motor.
Stand 1,2,6,9 drive 500HP DC motor.
Stand 10 & 11 600 HP DC motor.
Stand 12 & 14 800 HP DC motor
Discharge

10. Schematic illustration merchant mill

11. CONCLUSION
 Familiarized with the environment of a steel plant.
 Studied and observed the manufacturing process of steel – from raw
material handling process (by reclamation and tapping processes) to
finishing.
 Observed the functioning of Gas Cleaning plant, Dwight-Lloyd Sinter
Machines and manufacturing of Thermo Mechanically Treated (TMT)
bars.
 Performed Magnetic particle inspection and Ultrasonic testing for
detection of surface and bulk discontinuity respectively .