Abstract The present invention relates to a furnace for industrial use having a device for elevating the pressure of a combustion gas to be fed therein, which, in a part of its combustion zone is provided with a number of projecting jet nozzles being adapted to provide to the upper and lower portions of the said combustion zone high speed jet zones, each at a determined distance from substances to be treated, such as, steel ingot or blooms, wherein a high temperature combustion gas which has been fed from another combustion zone is jetted out from the said nozzles under high speed into the said high speed jet zone whereby a heat transfer is efficiently conducted therein between the said gas streams and the said substances by utilizing the high coefficient of heat transfer occurring on the surface of said substances due to the said high-speed gas streams, characterized in that a device for elevating the pressure of the said combustion gas is provided in the interior of a supply duct into which the said high temperature combustion gas is fed, being extracted from the said other combustion zone, whereby a small amount of high pressure air or low temperature exhaust gas in a flue, which has been exhausted from an industrial furnace, is jetted out into the supply duct by said device with an ejector nozzle under high speed thereby to elevate the pressure of the said high temperature combustion gas.
In combination a reheating furnace for industrial use, said furnace comprising: a pluralitY of longitudinally extending combustion zones receiving in sequence, substances to be treated, one of said zones comprising a plurality of longitudinally spaced jet nozzles facing said substances and set a predetermined distance therefrom, duct means commonly connected to said jet nozzles and fluid connected to another of said combustion zones for bleeding high temperature combustion gas therefrom, and ejector nozzles within said duct means facing downstream from the duct connection to said high temperature combustion zone, pipe means fluid coupling said nozzles with the low temperature exhaust gas from said furnace, and blower means in said pipe means upstream of said nozzles for increasing the pressure of the low temperature gas stream passing through said pipe whereby, jetting of a relatively small amount of high pressure low temperature gas into said duct means under high speed elevates the pressure of the high temperature combustion gas bled from said another combustion zone to utilize the high coefficient of heat transfer as to the surfaces of the substances due to the high speed gas streams emanating from said plurality of longitudinally spaced jet nozzles.
Claim 2
Dependent Claim
195 words
In combination a reheating furnace for industrial use, said furnace comprising: a pluralitY of longitudinally extending combustion zones receiving in sequence, substances to be treated, one of said zones comprising a plurality of longitudinally spaced jet nozzles facing said substances and set a predetermined distance therefrom, duct means commonly connected to said jet nozzles and fluid connected to another of said combustion zones for bleeding high temperature combustion gas therefrom, and ejector nozzles within said duct means facing downstream from the duct connection to said high temperature combustion zone, pipe means fluid coupling said nozzles with the low temperature exhaust gas from said furnace, and blower means in said pipe means upstream of said nozzles for increasing the pressure of the low temperature gas stream passing through said pipe whereby, jetting of a relatively small amount of high pressure low temperature gas into said duct means under high speed elevates the pressure of the high temperature combustion gas bled from said another combustion zone to utilize the high coefficient of heat transfer as to the surfaces of the substances due to the high speed gas streams emanating from said plurality of longitudinally spaced jet nozzles.
Claim 3
Dependent Claim
21 words
The reheating furnace of claim 1 wherein said high speed jet zone is contiguous to the preheating zones of said furnace.
Claim 4
Dependent Claim
21 words
The reheating furnace of claim 1 wherein said high speed jet zone is spaced from the preheating zone of said furnace.