Mobarakeh Steel Co.

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Mobarakeh Steel is one of the largest industrial complex in Iran and has been established and commissioned after the revolution and entered into operational stage in early 1993.

This company is located at 65 kms from south west of Esfahan which covers a land of 35 kms and has an annual capacity of 4 mt/years of flat steel products ranging in thickness from 0.18 mm to 16 mm in the from of hot and cold rolled coils and sheets, tinplate sheets and coils , galvanized and prepainted coils.

Contents 1 Manufacturing Units 1.1 Iron making 1.2 Steel making 1.3 Hot strip mill 1.4 Cold rolling mill 1.5 Tinning line 1.6 Galvanizing line 1.7 Prepainting line 1.8 Compact Strip Production Area (Saba) 2 External Links

[edit] Manufacturing Units

• Iron making
• Steel making
• Hot strip mill
• Cold rolling mill
• Tinning line
• Galvanizing line
• Compact Strip Production Area (Saba)

The iron ore or raw material for Mobarakeh Steel Company is supplied from Golgohar and Chadermaloo mines and is transported to MSC by rail and after discharging in car dumper it is shifted to raw material storage yard. Iron ore powder should be converted into pellets in pelletizing plant with diameters of 8 mm to 10 mm .The indured iron oxide pellets after reducing in direct reduction planet and removing oxygen will be converted into DRI (soponge iron). The sponge iron along with iron scrap would be melted in electric arc furnaces.The liquid steel after discharging from furnaces shall be stirred and purified in secondary purification unit. The chemical compound of steel should be produced according to customers order and then transported to casting machines for producing slab.

The slabs after cooling and conditioning will be transferred to Hot rollind mill and this unit these slabs are preheated and then are rolled in different phases for producing hot coils of 1.5 mm to 16mm in thickness that a part of which will be shipped to the market and the rest would be transferred to Hot finishing mill for performing complementary works and changing the hot coil into hot sheet or is sent to cold rolling mill for decreasing the thickness of strip up 0.18mm. A part of cold rolled coils would be dedicated for tinning, Galvanizing, and prepainting lines and in these lines they are processed for delivering to domestic and word wide markets. This complex is consisted of different plant units , out of which 10 plant unit are considered as the main production line and the rest are rated as the auxiliary and back up units.

[edit] Iron making

The iron making plant is consisted of 4 units:

• 1- Raw materials storage yard

The iron ore (iron oxide ) is transported to MSC by rail from domestic mines such as Golgohar and chadermalou in kerman and Yazd provinces and after discharging iron ore in Car dumper , it is shifted to raw material storage yard via conveyor belts. Stacking and Reclaiming machines which work back and forth for transferring raw materials to stock piles and vice versa.

• 2- Pelletizing plant

The iron ores with big grain size of Golgohar mine will be converted into fines by ball mills of this plant and after mixing with Chadermalou's small grain size iron ores and bentonite as an adhesive in blending machines it would be changed into pellets with diameters of 6 mm to 25 mm and then are screened by a two- story roller screen . These pellets would solidified in induration tunnel or furnace at a temperature of 1280 degrees centigrade.

• 3- Lime production plant

The limestone is supplied from Hozmahi mine, which is located at a 17 kms from MSC. There are two rotary kilns in which the limestone will be calcinated at a temperature of 780 to 1050 degrees centigrade. The calcinated lime after screening may use in making plant. In meantime , a protion of calcinated lime is consumed in pelletizing plant , briquet making and producing industrial water.

• 4- Direct Reduction plant

The indured iron oxide pellets are charged into Midrex shaft furnaces after screening micro grain ( smaller than 5mm) . Then two reducing gases , which are derived from cracking of natural gas (CH4) or methane in the gas reformer and consisted of Co and H2. These two gases are injected into the furnace where the oxygen of the pellets would be combined with them resulting in CO2+H2O. with removal of oxygen , the reduced pellets are discharged from the shaft furnaces, which are called sponge irons . After screening sponge irons they should be transferred to steel making. In the meanwhile , the sponge irons with a diameter smaller than 5 mm will be sent to briquet making unit and wil be produced briquets with diameter more than 25 mm and then along with sponge iron are transferred to steel making.

[edit] Steel making

• Steel Making and Continuous Casting plant:

The sponge iron or DRI would melted in 8 electric arc furnaces with capacity of tap to tap for each furnaces of 180 to 200 tons in steel making plant along with iron scrap and lime. The liquid steel should be stirred and purified with injection of oxygen and other metallurgical methods applying of 4 ladle furnaces. Then it will be sent to the 4 double-strand continuous casting machines wherein the liquid is to be converted into slabs with the length of 9 m to 10 m and the width of 650mm to 1880 mm and the thickness of 2200 mm.

• Slab Cooling and Conditioning plant:

In this unit the incoming slabs would be cooled and scrafed manually and automatically if needed

• Steel Making and Continuous Casting plant:

The sponge iron or DRI would melted in 8 electric arc furnaces with capacity of tap to tap for each furnaces of 180 to 200 tons in steel making plant along with iron scrap and lime. The liquid steel should be stirred and purified with injection of oxygen and other metallurgical methods applying of 4 ladle furnaces. Then it will be sent to the 4 double-strand continuous casting machines wherein the liquid is to be converted into slabs with the length of 9 m to 10 m and the width of 650mm to 1880 mm and the thickness of 2200 mm.

• Slab Cooling and Conditioning plant:

In this unit the incoming slabs would be cooled and scrafed manually and automatically if needed.

[edit] Hot strip mill

• Hot Strip mill:

The slabs are transferred to this plant, then they would undergo preheating 4 preheating furnaces at a temperature of 1280 degrees centigrade and after passing through roughing and finishing stands they will be rolled into coils of 1.5 mm to 16 mm in thickness. The annual capacity of this line is 4 mt per year.

• Hot finishing plant:

In this the complementary works such as surface stress relieving , skin pass , improving mechanical properties, strengthening and shearing in heavy gauge and light gauge to the sizes of 1 m to 12 m will be done.

[edit] Cold rolling mill

Part of the produced coils in Hot strip mill are transferred to Cold rolling mill in order to improve their quality and processes executed in different sections such as pickling , decreasing thickness, annealing , tempering and final skin pass processes for betterment or further mechanical and metallurgical characteristics as well as shearing , slitting and corrective lines are used and finally the products are packed in the form of coil and sheet.

[edit] Tinning line

Mobarakeh Steel tinning line has been designed on the basis of electrolytic cleaning and ferrostan process. This line has a capacity of 100,000 t/y and its products are delivered to the market in the from of coil sheet . The required steel sheets for tinnng line are rolled in the two-reversing stand mill.

[edit] Galvanizing line

Mobarakeh Steel Galvanizing line has been designed on the basis of hot dipping process with a capacity of 200,000 t/y. The advantages of this galvanizing process respect to others are to be economical, possibility of high thickness coating, high strength and zinc coating adherence. The products of this line are delivered to the market in the form of coil.

[edit] Prepainting line

Mobarakeh steel prepainting line is in length of galvanizing line and has been designed on the basis of roller coating with a capacity of 100,000t/y and the products of this line are delivered to the market in the form of coil. The advantages of this line are :high speed , low paint consumption , and environmental friendly.

[edit] Compact Strip Production Area (Saba)

Profile: The construction of Saba Compact Strip Production Area started in early 1997 and has been exploited with the first test in the electrical arc furnace in late 2002.

This area is able to produce hot strip in the latest design of CSP Thin Slab continuous casting /rolling plant with a capacity of 700.000 t/y which is capable to expand with 1.4 million t/y and is designed for a later expansion with 2.8 million t/y.

Products specifications:

• A: Quantitative:

Hot Strip in thickness between 1.5 to 12.5 and in widths between 800 to 1560 mm and capacity of 700.000 t/y.

• B: Qualitative:

Commercial, Drawing, Deep Drawing, High weldingability, Structural for engineering and stannite stainless application.

The features of Saba CSP Area

• A: Production of Thin Slab with maximum 50mm in Thickness
• B: connection of thin slab caster with rolling
• C: Possibility of secondary metallurgical equipment including L.F and V.O.D for production of high-quality steel and stainless steel.

CSP process

CSP is the leading thin casting and rolling process for efficient production of Hot Strip. The continuous process decisively shortens the production chain form liquid steel to finished strip, The capital and operating costs being acknowledged throughout the world to be extremely favorable when compared with competing plants. Optimal utilization of the casting heat and constant temperatures during hot rolling are the hallmarks of this technology.

CSP hot strip is distinguished by its outstanding dimensional accuracy, metallurgical consistency and an excellent quality surface.

The main facilities in Saba CSP Area:

• Electric arc furnace with scrap yard
• Ladle Furnace
• Vacuum decarbonisation with oxygen injection (V.O.D)
• Tine slab caste
• Equaliser furance
• Hot strip mill
• Coiler

The main units of Saba:

Steel making

• Raw material Storage yards (scrap yard, DRI storage sylos, Ferro Alloy Storage)
• Electric Arc Furnace with a capacity of tap to tap 150t
• Ladle Furnace, Slag rake, Vacuum degassing, Vacuum decarbonizing , Trimming Station
• Dust catcher equipment

Thin Slab Casting

• Ladle turret, tundish car by submerged casting
• Funnel type mould for production of thin slab with exit thickness of 60mm
• A set of segments from 0 to 7
• Rotary descaler, pendulum shear

The function of segments on one hand cause curvature they cause slab leading, slab final leveling and reduction of slab thickness while the internal part of the slab is still in the form of liquid and soft reduction happened and it would be reduced to 45 or 50 mm and on the other hand they causes improvement in slab quality and monotony in chemical composition and crystalline structure.

Hot Strip Mill

• Heating tunnel with the 250m long
• The 6-Stand rolling mill equipped with the latest adjusting mechanisms and control systems (Balancing, Shifting, HAGC) for dimensional accuracy
• Cooling Base, Coiler, Coil Transport, Packaging, Marking and Weighing

In comparison with usual process, the exit slab from casting with the temperature of 850 C◦ enters into the heating tunnel and the temperature will reach to 1150 C◦. Therefore, there is Energy saving because of hot charging and it is not necessary to cool and to reheat it, While the 50mm thickness of thin slab compared to 200mm of usual process has much more reduction in costs and amortization.

[edit] External Links

Offical webiste