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US 4,406,618 AGranted
Method of operating continuous heat treatment furnace for metal strip coils
AssigneeKawasaki Steel Corporation
InventorKimio Maeyama
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AssigneeKawasaki Steel Corporation
InventorKimio Maeyama
Estimating the term…
A method of operating a continuous heat treatment furnace for metal strip coils includes steps of enclosing them in muffles in the furnace supplied with an atmosphere gas containing a combustible gas such as hydrogen and feeding the muffles into and through the furnace having therein heating, soaking and cooling zones. According to the disclosed method, at least part of the heating and soaking zones is heated by direct firing heating with a fluid fuel with excess air and combustible gas leaked from the muffles into the furnace is burnt in the furnace with the aid of the excess air. Combustible gas leaked from the muffles into the cooling zone is diluted with air forced into the cooling zone to make the combustible gas incombustible and thereafter to exhaust it out of the furnace, thereby eliminating ignition means for the combustible gas in the furnace and particular precaution for preventing an ignition failure.
In a method of operating a continuous heat treatment furnace, which furnace is divided by an intermediate door into heating, soaking and cooling zones, said method including steps of enclosing metal coils, which have been wound after being rolled, in muffles, and supplying the muffles with an atmosphere gas containing hydrogen gas, and feeding the muffles into and through the furnace so as to subject said coils to heating, soaking and cooling, the improvement which comprises heating at least part of said heating and soaking zones by direct firing-heating with a fluid fuel with excess air, burning in the furnace with the aid of said excess air combustible gas leaked from the muffles into the furnace, supplying an amount of air into said cooling zone so as to dilute combustible gas leaked from the muffles into said cooling zone and render it incombustible, and exhausting thereafter the incombustible gas out of the furnace.
Dependencies are inferred from the claim text.