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Metal Melting Furnaces
Sub :- Manufacturing process – 2
Bhavik Nakrani_140990119027_MP2_2141908
Ankit Panchal_140990119028_MP2_2141908
Raj Parekh_140990119029_MP2_2141908
Dwij Patel_140990119032_MP2_2141908
Metal Melting Furnaces THE FURNACES USED IN METAL CASTING ARE AS FOLLOWING:.
Cupola Furnace Electric Arc Furnace Induction Furnace Metal pot Furnace
Cupola Furnace
Cupola furnaces are tall, cylindrical furnaces used to melt iron and ferrous alloys in foundry operations. Alternating layers of metal and ferrous alloys, coke, and limestone are fed into the furnace from the top.
Preparation of cupola. Firing the cupola. Soaking of iron. Opening of air blast. Pouring the molten metal. Closing the cupola.
Operation of Cupola
This zone is the zone between top of the
sand bed and bottom of the tuyers.
This is also called well of the cupola,
molten metal is accumulated here
between taps.
Zones
Crucible Zone
- situated 150 to 300 mm above the top
of the tuyers.
-The actual combustion of fuel occurs in
This zone using oxygen in the air blast.
-A lot of heat Is liberated in this zones
and is supplied to other zones.
Zones Combustion Zone
- Some heat is also evolved in this zone due to oxidation
Of silicon & manganese. The temp of this zone is of 1550
to 1850 C.
- Because of this temperature molten drops of CI pour
into the heart.
- Product : co2 , SiO2 and MnO2
Reaction in this zone
C + O2 ————> CO2 + Heat
Combustion Zone
- Extends from the combustion zone to top of the coke bed.
- CO2 produced in previous zone reduces to CO and temp drops to 1200 C.
- Because of reducing Atmosphere in this zone the charge is protected from oxidation.
Reaction in this zone
CO2 + C ————> 2CO - Heat
Zones Reducing Zone
- Extends from 1st layer of metal charge above the coke bed upto the height of about 900 mm.
- Temp : 1600 C which causes CI in the charge to melt.
Reaction in this zone 3Fe + 2CO ————> Fe3C
+ CO2
Zones Melting Zone
- Starts from above the melting zone and up to bottom of the Charging door.
- Alternate layers of coke, flux and metal charge are preheated in this zone to temp of about 1100 C before entering melting zone.
Zones Pre-heating Zone
Reaction in this zone FeS + CaO + C ————>
Fe + CaS + CO
- Extends from above the pre-heating zone to top of the cupola.
- Carries the flue gases and discharges these gases to atmosphere.
Zones Slack Zone
ELECTRIC ARC FURNACE
The Electric Arc Furnace (EAF) uses three vertical carbon rods as electrodes for producing arcs, striking on to the charge and heating it to the required temperature.
Charge is melted by heat generated from an electric arc High power consumption, but electric arc furnaces can ‑
be designed for high melting capacity Used primarily for melting steel
Induction Furnaces
Uses alternating current passing through a coil to develop magnetic field in metal
Induced current causes rapid heating and melting
Electromagnetic force field also causes mixing action in liquid metal
Since metal does not contact heating elements, the environment can be closely controlled, which results in molten metals of high quality and purity
Melting steel, cast iron, and aluminum alloys are common applications in foundry work
Metal Pot Furnace
Relatively low melting point alloys like alloys of aluminium,magnesium,zinc,lead or tin can be melted in a metal pot usually made of cast iron or steel.
The metal pot is supported by its lid in a stationary fired by gas, or oil.
The products of combustion are discharged through a flue and do not come into contact with the molten metal.
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