US2191438A - Furnace - Google Patents

Description

v Patented Feb. 27, 1940 I vhot gases tend to'flow f, *2,191,438 `FUruvAoE Walter n. Breeler, Fredonia, N. Y.

` Application 'ltlarcho 21, '1 2 claims.

My invention relatesto furnaces, andjparticu- -larly to vfurnaces'of the'car 'or movable hearth type.

Heat, in furnacesof this type,v is usually supplied from-burners 4positioned atlthe topr of the furnace or behind bridge walls near the top,` and -heat distribution iis accomplished-by the lflow of hot gases from the burnersthrough kthe interior of the furnace to flue outletsin the side walls at about the level ofthe hearth. In the-ordinary type of furnace with the burners projecting through the side walls near the top thereof-the onally downward and across the interiorof the furnace directly to the ue openings inthe side wall opposite the burners, and this path of`v hot gas iiow leaves a more or less cool lor"dead Zone inthe lower central portion of ther furnace. Because of this dead zone, an excessively long time vis required to heat the bottom andv central partof the charge on the' hearth and, in many instances, these portions of the charge never are heated to the correct temperature.

In order to produce a moreuniform: heat distribution, it has been proposed to build a movable hearth having combustion chambers or flues therein running parallel to thefront of the furnace. Aligned with the axis of each such flue,

is a burner located inthe side wall of the furnace and these sources o-f heat serve to bring the bottom of the charge up to the desired temperature. 'Ihis arrangement also reduces to heat the furnace.

However, the use of such combustion chambers or fiues in the hearth make it necessary to build high piers of fire brick which are so easily broken and so. rapidly' eroded b-y the hot gases that, in spite of continual repairs, thelifer of a hearth of this type is relatively short. Moreover, such flues extending transversely of the hearth weaken the top thereof so that only light charges can be carried. f

Another means has been suggested for heatin the center of the charge by. the use of similar nues in the hearth running parallel to the front of the furnace and connecting with the side wall flues. However, since the movable hearth is really the top of a platform car, and clearance must be provided between the side walls of the furnace and the carin order that it may bemoved into and out of the furnace, there is always an open space between the flues in 'the hearth and the side Wall flues. e s

The principal objects of vmy invention are to provide a furnace of from.- the burners diag the time required vthe car type capable of iesafseriai No. y.2651169 'tions'and arrangements thereof-described belowv andvin` which the vcharge x UNITED sra'rgs @PATE-NT jo-Fricr; i j

and illustrated in the accompanying drawing in which- Fig, 1 is a plan view of my furnace with'fpartf. broken` away to. show the interior thereof;

Fig. 52 isa longitudinal vertical section of rthe 'furnace;and.. l 9` v 'Fig "3ds a section of Fig. 2 inthe Lplane 33.r Referring to the drawing, the furnace is represented generally by the numeral I and comprises sidewalls 2, a rear wall 3 and a top- 4, the latter preferablybeing arched asshown in Fig. 3. The front of the furnaceis closed'by the vertically sliding gate. o-r door 5 provided, at the bottom, with a tongue or projectionl 6 adapted to fit in a slot 'I in the hearth forming theitop of car 9. The hearth or topof the car and the walls of the furnace are formed of refractory material, and the car is provided with the `usual supportingwheels II! which ride on rails IIso that it may be rolled into or out of the furnace. The interior of the furnace is heated by Ameans of burners extending into or through upwardly inclined tuyres I2 in the side walls of the furnace and ywhich open beneath ythe burners, the sidewalls are' provided with vertically extending flues I3 whichcommunicate with the interior of the furnace at the level of the -top of the hearth through openings I4, and the rear wall also is provided with a .vertical flue I5. The hearth or top of the car is provided with a longitudinally-extending, centrally-disposed ue I6 having spacedopenings I1 in the the arch 4.` Between top thereof communicating with the interior of i merely by pushing the'car firmly `against the rear wall of the furnace.

In operation, the car, with the charge IS supl ported in spaced 2?, and also having the bars or ingots, illustrated as constituting the charge,` arranged in spaced relation to each other, free circulation of hot gasis'rprovided thro-ugh .the charge, is pushed into the furnace until the wall 3 of the furnace. The nue I6, then registers with `hearth abuts the rear open rear end of the relation to the' hearth on blocksA as shown in Fig. 3, so that` in the direction shown by the arrows 2l the opening in the back wall of the furnace communicating with ue l5, and the gate or door is lowered to close the furnace as shown in Fig. 2. Hot gases from the burners enter the furnace in Fig. 3, and the arrows below the arrows 2| show generally the circulation of the hot gases through all parts of the charge. Some of the hot gases ow over and through the load and out the flues i3 in the side walls, while other currents of hot gas pass. downwardly through the charge, through the openings il in the top of the hearth, into the longitudinally extendingue i6, and out the flue E5 in the rear Wall 3. In this way the hot gases are brought into`contact with all parts of the charge which is quickly and uniformly heated thereby.

While I haveillustrated only one longitudinallue in the hearth or top of the car with a pluraiity of spaced, vertical vents or openings extendingtherefrorn, it is to be understood that increthan one ilue may be used in the top of the Cardi desired and that the vents therefrom may, instead oi' extending vertically, extend in any desirable `direction in order to provide proper circulation of the hot gases through the charge.

While I have described my invention in its preferred embodiments, it is to be understood that the words which l have used are words of description rather than of limitation. Hence, changes within the purview of the appended claims may be made without departing from the true scope ythrough said yterior of said furnace near the top and spirit of my invention in its broader aspects.

What I claim is:

1. A furnace of the characterdescribed ccm-` prising a longitudinally-movable hearth having a longitudinally-extending flue therein communicating with the interior of said furnace through openings in the top thereof, a rear Wall having a ilue therein communicating with the flue in said hearth, side walls havinga plurality of spaced flues therein communicating with the interior of said furnace `through openings at about the hearth level, an arched roof on said furnace,`and a plurality of upwardly inclined tuyres extending side Walls and opening into the inthereof for introducing heated gas into said furnace.

2. A furnace of the character described comprising a longitudinally-rnovable hearth having a longitudinally-extending ue therein communicating withthe interior of said furnace through openings in the top thereof, a rear Wall having a flue 'thereincommunicating.mth the nue in said hearth, side walis having a plurality of spaced ues `therein communicating with the interior of said furnace .through openings at about the hearth level, an arched roof on said furnace, and a plurality of tuyres extending-through said side walls and opening into the interior of said furnace nearthe top thereof for the reception of iiuid burners. u

` WALTER R. BREELER.

Images