Autotherm Equipments Corporation is well known manufacturer,exporter and supplier of Cokeless Cupola Furnaces at market leading price from Coimbatore,, . EcoMelt Cokeless Melting Furnace is a Vertical Shaft Melting furnace and was as a melting unit for Cast iron without use of coke as in a conventional cupola. The development of the cokeless cupola began in the United Kingdom at the foundry of Hayes Shell Cast Limited in the mid s. A pilot furnace was built.
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The metal is pre-heated in the upper part of the furnace and melts just above the spheres; it is then superheated as it trickles down over the spheres.
Year of fee payment: We have discovered that slag control is essential to the correct operation of a cokeless cupola cupoal opposed to being of minor importance as was previously felt. Based on its principle, the cupola furnace is a shaft melting furnaceit is filled with fuel cokemetal charge pig ironcirculation material, scrap steel and slag -forming additives limestone from the top. Search Expert Search Quick Search.
The heat in the counter flow is transferred to the top-fed material. The charge material melts, is superheated while it is in contact with the ceramic bedding and drips into the hearth.
As can be seen in Fig.
As a result, for same quantity of molten metal, much less CO 2 is emitted. A method cokeess to claim 6 wherein the silica comprises broken bottles, jars, gravel.
Wesman Group of Companies, Kolkata. At the same time, flux is still necessary to absorb the material originating from wear of the furnace lining and whilst in some cases a similar lining is used and the action is therefore similar, the actual lining consumption is much less, so here again there is a difference resulting in a lower need for a flux. The carbon content of the metal can be easily altered by changing the injection rate at the control panel.
US5294243A – Method of operating cokeless cupola – Google Patents
The rate of injection can be controlled. It is therefore very important to control the flux additions in order to obtain the correct xupola of the slag so that the furnace can operate smoothly, but at an economic cost. This means a considerable improvement over cold-blast operation. Cokelss present in the rare occasions that the operator of a cokeless cupola considers how much fluxing agent to add his instinct from working with coke cupolas where the precise amount of fluxing agent does not matter – so long as there is enough is to shovel on a lot of fluxing agent, and then shovel on another few shovelfulls for luck.
The hot flue gas from the natural-gas-fired burners flows through and superheats the layer of ceramic spheres and ensures that the charge column is thoroughly preheated.
Only the simplest form of fume control is necessary and a simple wet cap will enable the cupola to meet all known environmental standards. In both cases when the slag flows it is sufficiently fluid to flow easily. EXAMPLE II A cokeless cupola operating with a clean charge and with what were mistakenly thought to be correct proportions in the charge including 12 Kg of dollastone per charge was found to exhibit very rapid consumption of the spheres, with the consequence that the bed almost vanished by the end of an eight-hour shift, resulting in insufficient superheating and low metal temperature.
Fives Pillard Deutschland GmbH
furnacce Trials established that iron of suitable temperature and composition could be tapped directly from the furnace without any superheating. In pressurized siphon operation, iron and slag do not accumulate in the furnace but are immediately drained after dripping off.
During intermittent tapping the slag is kept pent up in the furnace and is released only at intervals. After introducing the ceramic bedding on the water-cooled ccupola, the empty furnace is preheated for about 45 minutes. Cupolz is the purpose of the addition of limestone to the charge in the furnace; the limestone acts as a flux to absorb all these unwanted furnacs and form a slag which can be easily removed from the furnace and handled outside.
If insufficient fluxing agents are added, the result is a slag which is viscous rather than fluid, and it does not flow easily through the cokeess. The principle of the design is highlighted in the diagramatic drawing below. In the cokeless cupola a flux or slag is still required for some of the same reasons as in a coke-fired cupola, but there are some major differences. In both cases the amount of recarburiser depends on charge makeup and final analysis required.
Dust removal can be accomplished by wet washer or dry means fabric filter ; today, fabric filters are considered state of the art. The lining may be consumable and may comprise a silica ganister, or for certain applications a lining with a high alumina content.
The lower slag volume that results in the operation of the cokeless cupola is not a problem in intermittent tapping and is certainly an advantage for slag disposal. The grate supports the specially developed refractory spheres shown in right. It makes possible the production of high quality metal much easier for the foundryman, and hence his ability to produce good castings is much improved. The comment was “What does not come out the top is more important than the metal from the bottom”.
In a coke-fired cupola it is important that the carbon in the coke should be easily released from the coke so that it can act both as a fuel, generating the necessary heat, and as a source of carbon for the metal, primarily where the metal is iron or a ferrous alloy. Pig iron is the most expensive raw material in a cupola charge whereas steel scrap is cheaper. The combination had a similar composition to what had been used previously, i.
Generally limestone or dollastone is used as the fluxing material, or sometimes a mixture of the two. As this is a considerable growth area in India, it offers foundries an additional advantage over competitors who are still using a conventional coke cupola. Below the grate are the burners which are operated to give partially reducing conditions inside the cupola to reduce oxidation losses.
The bridging was found to have been due to the sticky slag being thrown back up the shaft and coating the charge. The main features are the water cooled grate, consisting of steel tubes which may be coated with refractory for insulation on smaller cupolas as shown left.