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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Thus, it is possible to express a defined combustion ratio eq. Thus, the required energy is generated in the cupola itself, i. A method according to claim 1 wherein the cupolz has a furnace lining which has a high alumina content.
Cost and consumption of fuel are taken from different sources and are average values. Pig iron is the most expensive raw material in a cupola charge whereas steel scrap is cheaper. These spheres form an essential part of the operation, both technically and economically. As there is no carbon pickup in the Cokeless Melting Furnace, this is added either by continual injection into the well of the Cokeless Melting Furnace or outside in an electric furnace.
The invention adds more flux materials than is conventional, preferably cokeeless silica in the form of broken bottles, so as to deliberately increase the volume of slag, improving the flow. This just goes to show that the “obvious” way of increasing slag volume – shovelling on several more shovels of limestone than is needed for our optimum ufrnace of operation results in excessive consumption of the spheres and subsequent decrease in the bed height and operational performance of the furnace.
However there is still cokelesa in the charge and sand sticking to the returns, and so these materials still have to be converted into a fluid slag.
Cokeless Cupola Furnaces Manufacturer,Cokeless Cupola Furnaces Exporter,Supplier in Coimbatore
The metal is superheated as it trickles over the spheres. Absence of sulphur makes the molten metal obtained from Cokeless Melting furnace suitable for conversion, after superheating, into Ductile Iron without going through the de-sulphurision process where temperature is reduced due to endothermic reaction.
The examples show the importance of slag control. Next Patent Thermal reclamation Some examples will now be described to illustrate cupolx can happen when a cokeless cupola is not run in accordance with the invention.
This control may involve deliberately increasing the volume of slag by suitable additions in order to operate a continuously tapped furnace smoothly. Best viewed in IE 7. In both cases the amount of recarburiser depends on charge makeup and final analysis required. However, this has a slight negative impact on carburization. Cokleess in a coke-fired cupola the tapping temperature is higher, which means that if the slag composition is not quite right the extra cuploa will still enable the slag to be removed quite easily.
A special compensating siphon is used to adjust the slag bath height according to the desired carburizationmaking it possible to change the dripping zone in the cupola seen from the siphon. Because of high fuel efficiency of Cokeless Melting Furnace, much less fuel is consumed for melting same quantity of metal compared to that in other melting furnaces.
The foundry industry in India is cupols expanding and many foundries have adopted electric melting, particularly for the production of ductile iron. A method according to claim 1 which further comprises the step of re-cycling slag removed from the furnace by re-introducing at least a portion of the slag as a component of the slag-forming fluxing agents.
A method according to claim 2 wherein limestone, dollastone is added to the re-cycled slag as another ffurnace of the fluxing agents.
Automatic combustion control and indication of condition fhrnace all important services can be provided, as shown below. The hot gases from the burners maintain the bed of spheres at high temperature and also preheat and melt the metal in the shaft. Apparatus for melting scrap. High draw speed plate blank continuous casting low carbon steel crystallizer protective slag.
During this process, the counter flow principle is used to transfer heat from the combustion gases to the charge until it is melted Figs.
In India this Cokeless Melting Technology has a special significance. This picture highlights conventional coke melting rightand the cleanliness of the cokeless cupola also operating, left.
A method according to claim 1 which further comprises the step of re-cycling slag removed from the furnace by re-introducing at least a portion of the slag as a component of the slag-forming fluxing agents. The flux addition will also depend on whether the furnace is to be tapped intermittently in which case a relatively low volume of slag can be handled, or is to be continuously tapped, in which case a higher slag volume is necessary for smooth operation.
The ckeless is superheated in passing through the bed and is then collected in the well prior to tapping out in any normal way. Running the furnace at low slag volumes makes the slag thick and can cause blockage of the slagging and tapping box.
Dust removal can be accomplished by wet washer or dry means fabric filter ; today, fabric filters are considered state of the art. The bridging was found to have been due to the sticky slag being thrown back up the shaft and coating the charge. A method according to claim 1 wherein sufficient flux materials are added to the melt to keep the viscosity of the slag below a critical value at which point the slag tends to be held above the heat-exchange bodies and has difficulty in flowing through the bed.
During continuous tapping the flow of slag from the furnace is continuous. It is sometimes necessary to add further materials such as a fluorspar which makes the slag more reactive to the ash so that fokeless better carbon pick-up and better temperatures in the furnace can be obtained.
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Thus with insufficient fluxing agents the furnace does not produce any metal at all. If more limestone were to be added in a cokeless cupola to maintain fluidity it would increase greatly the rate of consumption of the spheres, increasing the overall running costs as well as shortening the length of melting run that is possible. This control may involve deliberately increasing the volume of slag by suitable additions in order to operate a continuously tapped furnace smoothly.
This means that an operator continually has to release the slag by breaking the crust on the top of the box with a suitable bar, which is hot and heavy work. The existing electric capacity would be more than sufficient for any expansion as less than kW hrs per tonne are required for superheating and recarburising whereas generally more than kW hrs per tonne are required for electric melting.
Elimination of coke is a great relief to the foundry men as availability of coke is erratic and the price is highly fluctuating. With correct charge materials the sulphur content of tapped iron can be below 0.
Also, considering the shortage of power in India, it may be noted that when duplexed with Induction Furnace for production of Ductile Iron, the power requirement is reduced substantially. As can be seen in Fig. Generally limestone or dollastone is used as the fluxing material, or sometimes a mixture of the two. Moreover in many instances the cokeless cupola is operated as a long-campaign furnace as this is a more energy-efficient method of operation than a series of short runs and it forms an important part of the way the furnace is used.
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.
It is not possible to achieve zero sphere consumption, but we have discovered that there is an optimum consumption for different modes of operation.