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In order to reduce scale loss and coal consumption in the Re-heating

furnace following practices has been suggested by Technical Advisor to

be strictly followed from now onwards.

REDUCTION IN SCALE LOSS

During regular operation

In case of mill stoppage for 1-2 hours following steps should be taken by fireman and gasifire

operator.

The furnace temperature should be bought down to 1000 :C by opening damper After furnace reaching 1000 :C damper should be fully closed. After breakdown is over full gas should be taken and mill should start within hr to

45 minutes to bring the temperature for rolling.

And gasifire operation should run accordingly.The mill stops for more than 4 hours

Gasifire blower should be closed The furnace temperature should be brought down to 800 :C to 900 :C by opening

damper

Once the temperature reaches between 800 to 900 :C dampers should be closed. Gasifire and furnace operation should start in these way

Starting of gasifire: - 3 hours before

Starting of furnace: - 2 hours before

If the mill stops for few days.

Gasifire should be stop and pipe line , water seal pot should be cleaned properly Furnace temperature to be brought to 800 :C by opening damper. After furnace reaching 800:C the damper should be closed Furnace should be allowed to cool naturally upto 300-400 :C If there is any refractory work required then the furnace should be cooled down by

opening blower, to bring the furnace at room temperature so that mason or furnace

repairing workers can do their work in furnace.

NORMAL OPERATION OF FURNACE

Damper operation

Optimum furnace pressure should be kept in furnace and this should be checked by flowing

dust near the charging end or any inspection hole.

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If the furnace is at high pressure the dust will be thrown very fast and lots of heat will be lostfrom charging end or any opening of the furnace. This will also damage the roof of soaking

zone.

If the furnace is at lower pressure there will be suction of the dust inside the furnace and it

means there is in filtration of atmospheric air inside the furnace reducing the efficiency of

furnace.

There for the damper should be operated to run the furnace at slightly higher pressure than

atmospheric pressure.

REGULATION OF AIR FLOW TO THE BURNER

As there is no indication of flow rate of gas, air flow rate should be controlled by recently

provided valve in the suction chamber of blower

The air flow should be optimize by adjusting inlet valve of the blower with respect to rate of

increase of furnace temperature

In case of less gas the air flow rate should be reduced, whereas it should be increased when

gas increases depended on coal quality.

Under no circumstances the furnace temperature should be decreases whatever may be the

quality of coal.

The mill supervisor should record temperature of soaking zone and heating zone at every half

an hour, and if under any situation rate of rise of temperature is slow fireman should be

informed.

While recording the temperature after every hr the hole number of the inlet blower should

also be mentioned along with damper opening position.

REDUCTION IN COAL CONSUMPTION

Under no circumstances the blower & steam pressure should increase beyond 250 mm water

gauge.

If the gas generation is less fireman should informed to reduce air accordingly.

In case of good coal quality, coal dropping frequency should be increased by at list 1 minute.

Similarly in case of good quality of coal resulting in higher gas generation fireman should be

informed to increase air accordingly.

Gasifire operating should interact with shift in charge in case of any delay in the mill and

accordingly adjust the coal charging.

The role of gasifire and fireman is very important for reducing coal consumption /MT.

As for reducing the scale formation the total responsibility will be of fireman.