A REPORT

ON PRACTICAL TRAINING

TAKEN AT

BHILAI STEEL PLANT STEEL AUTHORITY OF INDIA LTD. BHILAI, CHATISHGAD

Date:- 06-06-2005 to 02-07-2005

Submitted To:- Submitted By:-

Prof. M.R.Baid Mr.Rahul Godara

HOD, Mech. Engg. II B.E. (Mech. Engg.)

J.I.E.T., Jodhpur

DEPARTMENT OF MECHANICAL ENGINEERING

JODHPUR INSTITUTE OF ENGINEERING & TECHNOLOGY

MOGRA, JODHPUR (RAJ.)

Ore handling plant

OBJECTIVES OF OHP: -

1. To reduces interferences of internal traffic movements and to

unload raw material.

2. Blending by making homogenous pile of raw material.

3. Keeping buffer stock of raw material and their uninterrupted

supply.

THE RAW MATERIAL ARE TRANSFERRED TO CONSUMERS SUCH AS: -

· Iron ore fines to SP2 & SP3.

· Iron ore to blast furnace. · Low silicon limestone to RMP2 & SMS2.

· High silicon dolomite to SP2, SP3 & SMS2.

EQUIPMENTS

· PADDLE FEEDER · WAGON TIPLLER · PUSHER CAR · STACKER · BLENDER BARAL

RECLAIMER · TRANSFER CAR · EXCAVATOR · TRAVELING FEED BINS · TRIPLER CAR · CRANE (EOT) · DOZER

· 3D EXCAVTOR

Blast furnace

There are 2 main section of the department:

1. Raw material section

2. Furnace section

Raw material section: Ø The raw materials used for the production of pig iron are:

Ø Coke (fuel), Iron Ore, Sinter (Fe-bearing material), Limestone

(Flux) & Mn-Ore and Quartzite (additives).

Furnace Section: Ø Blast Furnace is a vertical shaft furnace, enclose in a welded

shell, lined with fire-clay bricks of high alumina content.

Ø The walls of the furnace top are protected by steel refractory

lined plates cooling the shaft,

TOP CHARGING EQUIPMENT

The bell type chaging device (exhisting in BF 1,2 & 3) has a big bell, small bell with hoppers, gas seal, and receiving hopper; and receives raw material from an oval shaped receiving hopper. In BF-3 RCU (Rotating Charging Unit) is provided, by means of which charging can be distributed in desired sector inside the furnace BFs. #4,5,6 & 7 are equipped with paul gate, upper sealing valve, lower material gate and lower sealing valve. This system also has a gearbox to operate a rotating chute. The latter distributes the material inside the furnace peripherally in different rings. This facilities better distribution of charge inside the furnace.

CHARGING PROGRAMME: -

To facilitate smooth working of furnaces, the following

charging programme is normally practiced.

‘A’. Programme COC / COOCC / CCOOC

‘B’. Programme CCOO

Each charging cycle consist of 3 programmes of A & B

exclusively or in combination depending on peripheral

conditions. Generally in Bell-less Top Furnace the programme

selected is ‘B’ i.e. CCOO, C=COKE; O=NON-COKE i.e. ore,

sinter, Mn ore, lime atone or quartzite.

STOVES

Form bottom of the furnace the hot blast is blown into

the furnace through tuyers with the help of turbo-blowers &

hot blast stove.

Blast of Air reaches as follows: Cold blast CB Main Stoves HB Main Bustle pipe Gooseneck pipe Tuyer stock Furnace.

FLUSHING OF SLAG: TAPPING AND DISPOSAL OF HOT

METAL

Ø The furnace is provided with a tap hole, which is enclosed in a steel

cast frame and is cooled by two Tap hole coolers, which have their

own supply of water.

Ø The hot metal is tapped out at an interval of 1-2 hrs depending upon

the furnace condition.

Ø The usual way of opening the tap hole is to drill the tap hole until the

skull is reached. Oxygen lancing is carried out melt the skull.

Ø The hot metal continues to flow down the bend runner form,

which it is diverted into individual metal ladles.

At the end of tapping the tap hole is closed with mudgun, which is electrically or hydraulically operated

Fleets of 78-iron ladles car are available, out of which normally 48 are in circulation in cases all seven furnace are in operation.

Source of Raw Materials:

1. Iron Ore …. Dalli, Rajahara Mines

2. Lime Stone …. Nandini Mines

3. Manganese …. Balaghat Mines

4. Sinter …. Sintering Plants (SP-2, SP-3)

5. Coke …. Coke Ovens (Coke sorting

plants)

6. Converter Slag …. SMS – l l

Requirements for producing of one ton of Hot Metal

(Specific Consumption)

Iron Ore …. 459 Kg

Lime Stone …. 850 Kg(Depending on Sinter

Usage)

Manganese …. 800 Kg(50% in burden)

Sinter …. 35 Kg

Coke …. 08 Kg

Converter Slag …. 30kg

WORKERS TAKING OUT

MOLTEN IRON

FROM THE BLAST FURNACE

THIS IRON IS CALLED AS

PIG IRON