US2369419A

US2369419A - Heating furnace

Info

Publication number: US2369419A
Application number: US499946A
Authority: US
Inventors: Julius H Strassburger
Original assignee: National Steel Corp
Current assignee: National Steel Corp
Priority date: 1943-08-25
Filing date: 1943-08-25
Publication date: 1945-02-13
Anticipated expiration: 1962-02-13

Description

Feb. 13, 1945 J. H. STRASSBURGER HEATING FURNACE Filed Aug. 25, 1943 4 Sheets-,Sheet l Feb, 13, 19215 1. H. STRASSBURGER HEATING FURNACE Filed Aug. 25, 1943 4 Sheets-Sheet 2 lNvENToR Ju//us zrdsJw-Jer M Feb. 13, 1945 J. H. STRASSBURGER 369,419

HEATING FURNACE Filed Aug. 25, 1943 4 Sheets-Sheet 3 INVENTOR Feb- 13, 1945 J. H. sTRAssBURGER HEATING FURNACE Filed Aug. 25, 1943 4 Sheets-Shel# 4 NQ QM QN Nm IL www v Patented Feb.,13, i9451 FFICE JHEATING FURNACE l Julius H. Strassburger, Steubenville, Ohio, "assignor to' National Steel Corporation, a corporation of Delaware Applicatiennugustzs,1943,serialNoAssoie `1'7 Claims.

The present inventionirelatesto heating` furnaces for heating billetsybloonis,A slabs, bars and the like, `and more particularly to the apparatus at the discharge endof the furnace for' discharging therefromf the bars, billets, blooms, slabs, `or..`

the` like, which have beenv heated in the furnace.

In heating furnaces for heating bars, ;billets, blooms,s1abs `or'the likegit has been customary to'pass the material continuously or intermittently `through"theheating chamber or through. communicating heating and. soaking chambers and then "to `discharge the `material :from ,the

provides au skid :structure which will -carry the water cooling to the furnace hearth knuckleand which will `withstand the frigid service to which thexskids are subjected. Moreover; b'yfvirtue of the fact `that the skids which I provide vwillwithstandthe rigid conditionsito which they are subjected,.they will eiectua'lly depositthe material` s in` proper position o`n1th`e roll table.` The structure which I provide possesses the further advantage that it `isl inexpensive and :relatively simple from .thel manufacturingstandpoint. i

furnace at the dischargegend `by causing them x to slide orI roll downwardly by gravity alongeither "anfinclined` portion of the furnace hearthy oralong` water-cooled pipes spaced apartlto formparallel skids. the: rolls of a roll table at the lower end of the skids and `is carriedawayffroin the discharge end of the furnace bythe table. In general, theaA roll table extends at right angles to thefurnace but it'may extend in the same general direction as Vthe `furnace so that the Vmaterial maybe carried forwardly instead `of sidewise `awayfrom the discharge end of the furnace.

Considerable diiculty has vbeen encountered where the conventional water-cooled pipeshave been used as skids. When handlinglarge blooms or billets, the skids are subjected to severe bump-7 ing` and vibration andtheconventional water-W cooled" pipes will not withstand the severe service to which they are subjected. 'It hasbeen necessary heretofore to replace th'ewater-.cooled pipes `periodically;` This, naturally,` re'quiresza loss of production; i Moreover, when these Watereooled pipes become bent or^otherwise 'damaged by the severe treatment to which they are'subjected, theblooms. bi11etsbars, slabs, etc. donot move uniformly downwardly along the-skids andagt,

hence, the material is subjected to .severe treat- 'the desired position. i

. I have also foundthatY where ordinary-water- `cooled. pipes are used for skids the' Water ucoolingixr.

is not `satisfactorily carried to the 1 knuckle-or The material is generally deposited :on i

In the accompanying drawings Ihave shown,`

forpurposes of illustrationonly, one embodiment of my invention; In` the drawings I have ,shown `my invention as, `applied tot a` furnace for heatingl blooms, bars, slabs, etc., but it :willbe understood thatmy invention is` not limited to furnaces for heating` such articles but mayj be; applied generally to the discharge end of `any heating furnace in-whic'h the materialbe'ingiheated ispassed continuously or intermittently therethrough.

`Inthe drawings: r S

Figure I is]` a longitudinal', sectional view throughoue of `thelskids and the' supporting meansthereforlanda portion ofthe furnace adjacent thefdischargeend; i i l Figurez isya front elevational View showing i certainA parts of thestructure shown in.` Figure 1,

the rolls f :the `roll table being shown insection `and only azportion of the brickwork between the skids beingtshown;` i i Figure` Sis af horizontal Asection `taken above the.. skids and a part ofiltlierollfl table, the* brickwork betweenthe `skids"aridfseveral of the other shutting down ofthe furnace and a consecguientlli` i ment and is not deposited on` the roll :table in joint between the `furnace hearth andthe skids and that, consequently, `they afford no substantial protection` to the refractory hearth" at this point.

coursegmeans a loss in production. i The present i invention overcomes ftheV AJubilee-- As aconsequencean excesive4 amount` of i weartakes place at thispoint. and it isznecessary toperiodically. shutdown ithe furnace. This, of

tionable featuresof the conventionahski'ds. Itis `parts beingeliminated for purposesof clarity;`

Figure 4 is` a top plan view df one ofl the skids shown in Figure' 3l; i

Figure 5 is a side elevational view of the `skidt l showniin Figurel; and.` u

Figure 6` is avtransverse' sectional viewtaken` alongthe lineiVIe-VI ofFiguref. i

In the Venfibodiinent shownc inthe drawings the i furnace 2 is provided with the usualtopyfbottoni;` side andendrwalls. Thehearth or bottom `wallI 3; which is formedyof `aw layer of chrome brick 4; a layer 'of re brickiand ailayerof insulation `l5, c is\ supportedon f the structural" steel 'Work indicatedf` generally `byA the referencecharacter ;'l.

The hearth properterminates Within the furnace at apoint lspaced from the end'wall Biwhich hasthe dischargeopening 9 therein. `'-lhe skids, indicatedgenerally by` the reference character 1.0,. at the.` upper` endsV thereof, are positioned in'iabutting relation/With respect to'the hearth 'andk they bridgeuthearea betweenthe end of the hearth and the discharge opening 9 and extend slightly beyond the discharge wall so that material passing thereover may be discharged onto a roll table indicated generally by the reference character Ii. The discharge opening above the skids is normally closed by a door I2 which is pivotally mounted on the rod i3 carried by the angles I4. The angles I4 are supported by the channel I5 which extends across the discharge wall and acts as a reinforcement therefor. As is customary, the furnace door I2 is formed of a metal castingnand the inner face thereof is lined with a refractory I6. This furnace door'is normally in the closed position indicated in Figure 1, but whenever a billet, bar,

slab or the like is being discharged from the furnace along the skids, the door is moved to open position. The movement of the door from closed to open position is effected by means of an operating rod Il, the lower end of which is pivotally connected at I8 to the metal frame of the door. l

' When a billet `or the like is being discharged from the furnace, the door is raisedr and it passes downwardly alongthe skids I0 by gravity and is deposited on the roll table II. The roll table II is made up of a plurality of rolls I9 which are supported insuitable bearings 2U carried by a supporting frame `2L As stated above,.a plurality of spaced, watercooled skids bridge thespace from the end of the furnace hearthV to the roll table. Any suitable number of skids may be provided, depending .upon

-the character of the material to be handled by the furnace andthe lengthl thereof. These skids arebuilt-up structuralmembers and are of such charactenthatpthey .can withstand the severe treatment to which `they are subjected in use.

Each skid Ycomprises abottom plate 2l', side plates -or bars'28, anda top plate or bar 29. The side plates .28 .are supported on the bottom plate 2l and are positioned inwardly of the'edges of the bottom plate. A wide bottom plate is preferably employed in order. to provide support for the brickwork between'the skids and in order to give rigidity and strength to the skids. The lower end of each skid is closed by a closure plate .3% and an apron'platel. The apron plate 3| is welded or otherwise suitably secured Ato the bottom sidel of the top plate just short of the end thereof. and the closure plate 33, at one end, `is welded or otherwise suitably secured to the rear face of the apron plate 3l and-at the other end to the lower end of the bottom plate 21. As is indicated in Figures land 5, the one edge of the plate 3l! is bevelled to cooperate with the .upper face of the bottom plate 2'I at the end thereof.

The upper end of each skid' is closed by means of a transversely extending. closure plate 32.

This closure plate is preferably welded to the ends of the top and `side walls of the skid and to the top surface of the bottom plate at the upper end thereof.

The arrangement just ydescribed 'provides a completely enclosed chamber 33 through which water or some other Vcooling fluid maybe circu lated. The bottom plate of the skid has an opening 34 therein through which a water pipe 35 extends. The pipe 35 is bent intermediateits ends so that'it extends downwardly through the chamber 33 to a point adjacent kthe bottom end thereof wherethe water is"discharged from the pipe into the chamber 33. Water is fed to the pipe 35 by a pipe 36, one end of which is con- Y nected to the inlet header 3'! which extends transversely of the furnace adjacent the discharge end and supplies water to all of the pipes which feed water into the skids. water is regulated by a valve 38 in the pipe 35.

The bottom plate of each skid is provided with another opening 39 through which a discharge pipe 4I) extends. `This discharge pipe 4l) is posi tioned adjacent the upper end of the'skid and extends upwardly into the chamber 33 to a suflicient height to insure that the cooling fluid 'will reach the upper end of the skid. 'Ihe discharge pipe 40 extends downwardly from the skid and at the bottom end thereof is connected to a transversely extending pipe 4I. Separate discharge pipes 4I are provided for each, of the skids and they extend transversely beneath the furnace and are connected with a water box 42 which, in turn, is connected with a pipe 43 which `is adapted to empty into a sewer.

Supporting bars or plates 44 are provided near the lower end of each skid. These bars or plates form abutments against which the lower ends of the supporting plates 26 and the brickwork 8i between the skids rest. Each supporting bar it is welded to and mounted upon the bottomV plate 2'I and is welded to the adjacent side bar and the adjacent end of the top bar.

The upper end of each skid is provided with plates or bars 45 which extend beyondthe upper end of the skid and into the brickwork forming the hearth of the furnace. One end of each bar is welded or otherwise suitably secured to an end ofthe crossbar iii! and the adjacent side bar 28. The other end of each bar extends beyond the upper end ofthe skid and extends into the furnace hearth to a sufficient extent to reinforce the hearth and retard its deterioration. These bars or plates 45 are supported intermediate their ends by bars it which are welded thereto and 40 to the depending member 4l which is described It is posiwardly along the front face of the hearth of the furnace. This billet serves to strengthen the forward end of the furnace hearth and to prevent vdisintegration thereof due to the forward mo- 41 is provided with a hole 48 adapted to receive' a pin or bar 69 ,which extends transversely ci tion of the materialk being passed through the furnace which, as is evident, is pushed along the hearth by suitable pushing mechanism adjacent the charging end. The lower end of each billet the furnace hearth and beneath it, and assists in holding the skid and other parts in position.

The skids are supported in position at the forward end of thefurnace by the structure de scribed'Y below. The upper end of each .skid rests upon a hearth slab 50 which, in turn, is supported bya channel 5I forming a part of the structural steel supporting framework for the furnace. A welded supporting stand 52 is providedfor each skid. This supporting stand is formed of a top billet 53 and legs 54 which extend downwardly therefrom. These legs are likewise preferably7 made of billets and at their upper ends are welded to the lower face of the inclined topbillet 53. v The upper leg of the stand is supported on a plate 55 which `is supported-on the structuralr The flow of The upper end of this member is welded to the face of the crossbar 32 and the .uppei'endof the bottom plate 21.

tioned between Vthe barslili and extends downl the furnace.

o fraecasre ljsteel workforlthefurnace. Onefface of th'eupper l lleg 54 and thelupper end-.of `the-top supporting f member :53 abut the Slab 50.

be welded together .if desired,`$although ordi-` tlnarily. such welding is not desirable.` A trian- .lgular plate 56 is weldedwto the 4top facerof` the A plate 55 and the forward face of the upper leg 1511i in order to impart rigidity to the structure l The lowerlleg 54 of each stand rests upona 1 transverselyrextending bearing plate 5l' Whiclrlin Q Vturnpis supported by a `concrete pedestal v59. The

top member of the stand, theupper leg thereof and the bearing plate have holes thereinto re l ceive the water pipes mentioned above.

Each skid is provided with a downwardly er;-

l tending slab El! which is welded tothe bottom platenearthe lower end lthereof. Each sl'ahco- These parts 1 may operates with a transversely extending support l,

ing structure 6l which is ,adapted to support the lower end of the skid. This supporting member 6| rests upon theupperside of a boX-likestructure 62 which is formed of topand` bottom Achannels 83 and sideplates 64. This supporting boxlikestructure is held together and held in position and is `threaded at one end to receivea nut 6B.

` The rod` extends through the pedestal 59 andjs threaded at the other end to receive anut 6l.

`A bearing plate 68 `is `provided at this end of the 'by a rod 65 which extends through the plates` rod in order to protect `the pedestal which, as* is indicated, ispreferablyfmade 0f concrete. When the nuts are threaded on the rods, the box-like structure., is held together ,in the positionyindicated. A sleeve `Surrounds the rod A65 throughout thatportion which extends through the concrete supportingpedestal 59. A rod 1U extends `upwardly throughthe box-like supporting structurc and also through the lower portion of the `suppoitll. The upper endlthereof `is threaded and receives a nut 1l. In this way the supportl ing structure El is held in po-sition on` thebox- The ends of these tie Qrods. are threadedto receive .nuts 14,. and Whenlthese nutsare threaded in .place the supporting` member (ill and skids are 'held in proper position in respect of thef furnace.

There is a tendencyforthe skids to be `pushed forwardly by the movementof the material onto the` skids `at, the` point where `the skids `join 'the hearth .but the skids are restrained againstany such forward movement by the sup-` porting structure justdescribed.

It will be apparent` from this descriptionthat `in the event that any of "the skids areldamaged like structuref62.` "Tie rods 12 extend `through `openings inthe channel `13, which isa part 0f the structural. steel work of the furnace, and the l rear face of` thasupporting structure 6I.

for one reason or another they can be readily re- ,moi/,ed without any substantial shutdown of the furnace.` o l I In `the absenceof brickwork between the'skids the furnace `atmosphere would escape between themfand outwardly from the discharge end of embodiment of my invention, it will be under` l thereon; 1 Whenever @the Meehanite `strip-s1become A `worn,` they can .be readily replaced. l

lIt willbe apparent fromythexabovedescription thatthen structure which I provide possesses f greatxstrength and-will'withstand the severe conditionsto whichitis subjected in `normal usage.

`The skids. are built-.up structural members and possess suiiicient strengththat they will notbe `bent or `warped byxthe heat `and the rough treatment which they receive. `Also, it will be ap- `parent that the skids arexjoined intothe forn `ward end of the `hearth `in such a way that `the hearth is protected `against wear resulting lfrom the forward movement of thematerial thereover. It Willalso be` apparent that'the cooling" fluid is fed to the skids adjacent the lower end thereof and thent flowsupwardly therethrougha'nd` is dischargedtherefrom` at or adjacentthe knckle ofthe furnace hearth. This provides a constantly `flowing body of' water extendingfroni` the extreme l lower end ofthe skids to the extreme upper end thereof,iand9the knuckle of the furnace aswell as the skids will be kept relatively cool. "Also, any steam which forms cannot `be entrapped in the `skids but lwill pass through `the discharge pipe so that there will not be any possibility of hot spots developing at various points along theskids `and particularly at the junction between theskids and the furnace hearth.

While Ihave shown and described a preferred stood that it can be otherwise embodied within l the scope of the appended claims.

I claim:` 1.` A discharge `skid for a heating furnace having a hearth over which the material passes comprising bottom, top, side and end plates unitedV together toform. a chamber for a cooling fluid, means for supplying a cooling fluid to said l chamber adjacent one end thereof, meansfor discharging cooling I fluidfromthe other end However,` the space between the skids `is closed by brickwork ywhich restsl `upon plates 26 in the mannerindicated in Fig-` ure 2.

extent in normal operation. Consequently, `1

provide wearing strips; Bt `on "the top surfaces thereof. These are preferably made of Meehanite,

which is a heat-resistant and wearresistant aljloy. These strips extendfrom the upper end ci Unless provision is made toprevent it, `the` top .surfaces ofthe skids will wear to a substantial each skid to the lower end and the material rests thereof adjacent the junction betweenthe skid and the `furnacehearth 2L A discharge skid fora heating furnace having a hearth over which the material passes comprsing` bottom, top, side and end plates united together to, forma. chamber for a, cooling` fluid, means" for supplying the cooling4 fluid to said A,chamber adjacent the lower end thereof, means for discharging cooling fluid from said chamber at the upperend thereof, `and means carried by` the upper end of `the skid for connecting it with the furnacehearth. l.

3. A discharge skid for a heating furnace hav`` inga `hearth over "which the material `passes l `comprising bottom, top, side` and `end plates l united together to form acharnber for a cooling fluid, means for supplying a` cooling fluid to said chamber adjacent `the lower lend thereof, means for discharging cooling fluid` from the chamber `atxthe upper.endwthereofladjacent the junction between -the Skidandl the furnace hearth, and meansfcarried'byqthe` upper end of the skid for reinforcing the` endv offthe furnace hearth whichit is connected.

4s Asdischarge skid for heating furnaces comprising; bottom, top, side and end plates unitedk l together to formfa chamber for a coolingfluid,4

means` for circulating a cooling fluid through said chamber, and at least one longitudinally extendingjhearth reinforcing .plate carried by `one end of said skid.

5. A dischargeskid `for a heating furnace havf ing anhearth over Jwhichv the material passes lwith comprising bottom, top, side and end plates united together to form a chamber for a coolingfiiuid, means for circulating a cooling` fluid. through said chamber, and a vertically extending member depending from theupper end of the skid andl together `to form a chamber for a cooling fluid,y

said bottom plate extending sidewisebeyond the side plates to providesupporting surfaces, means for circulating a cooling fluid through said chamber, at least one longitudinally extending hearth reinforcing plate carried by the upper end of the skid, and a vertically extending member depending from the upper end of the skid and adapted to abut the end of the furnace hearth.

F1. Apparatus for discharging billets, blooms, bars `and the like from a heatingifurnace having a discharge opening anda hearth over which the material passes comprising a plurality of spaced, substantially parallel skids extending downwardly at an angle from the hearth to the discharge opening, each skid having bottom, top, sidey and end plates united together to form la chamber for a cooling fluid, means for supplying a cooling fluid to each of said chambers adjacent the lower end thereof, and means for discharging cooling fluid from the upper end of each of said lskids adjacent the junctions between the skids and the furnace hearth.

8. Apparatus for discharging billets, blooms, bars and the like from a heating furnace having a discharge opening and a hearth over which the material passes comprising a lplurality of spaced, substantially parallel skids extending downwardly at an angle from said hearth to the discharge opening, each skid having bottom, top, side and end plates united together to form a chamber for a cooling fluid, means carried by the upper end Y skids to the end thereof adjacent the furnace hearth.

9. Apparatus for discharging billets, blooms, bars and the like from a heating furnace having a discharge opening and :a hearth over which the material passes comprising a plurality of spaced substantially parallel skids extending from the end of the hearth to the furnace discharge opening, each skid having bottom, top, side and end plates \united together to form a chamber' for a cooling fluid and the bottom plate of each skid extending sidewise beyond the side plates to provide supporting surfaces, means for circulating a cooling fluid through each of said skids, and closure means extendingbetween adjacent skids and supported by the bottom plates thereof.

l0. Apparatus for discharging billets, blooms, barsand the like from a heating furnace having a discharge opening and a hearth spaced therefrom over which the materialpasses comprising a plurality of spaced skids extending at an angle downwardly between the end of the furnace hearth and the furnace discharge opening, each skid having bottom., top, side and end plates united together to form a chamber for a cooling huid, means for circulating a cooling fluid through each of said skids, means for supporting said skids, and means for maintaining the upper end of each skid in abutting relation with the end olf said furnace hearth.

11. Apparatus for discharging billets, blooms, bars and the like from aheating furnace having a discharge opening and a hearth spaced therefrom over which the material passes comprising a plurality of spaced skids extending at an angle downwardly from the end of said hearth to the discharge opening, each skid, having bottom, top, side and end plates united together to form a chamber for a cooling fluid, means for circulating a cooling fluid through each of said skids, at least one hearth reinforcing plate carriedv by the uprper end of each skid and extending into the furnace hearth, a stand having an inclined upper surface adapted to support each skid intermediate the ends thereof, and means for maintaining the upper end of each skid in abutting relation with the furnace hearth with the reinforcing plates extending into the hearth.

l2. Apparatus for discharging billets, blooms, bars and the like from a heating furnace having a discharge opening and a hearth spaced therefrom over which the material passes comprising a plurality of spaced sk'ids extending downwardly at an angle from the furnace hearth to the furnace discharge opening, each skid comprising bottom, top, side and end walls united together to form a chamber for a cooling fluid, means for supplying a cooling fluid to each chamber adjacent the lower end thereof, means for discharging the cooling fluid from each chamber adjacent the upper end thereof, a vertically extending member depending 'from the upper end of eiach skid and adapted to abut the end of the furnace hearth, said depending members` extending downwardly to a point below the bottom of the hearth, means cooperating with each of said depending members for holding them against vertical movement when in position against the end ofthe hearth, means for supporting each of said skids intermediate the ends thereof, and means for maintaining `the skids and the depending members ,thereon in abutting relation with the end of said hearth.

13. Apparatus for discharging billets, blooms, bars and the likefrom a heating furnace having a discharge opening and a hearth spaced therefrom over whichI the material passes comprising a plurality of spaced skids extending at an angle downwardly from the end of said hearth to the discharge opening, each skid having bottom, top, side and end plates united together to form a chamberfor a cooling fluid, means for circulating a cooling fluid through each of said skids, at least one hearth reinforcing plate carried by the upper end of each skid and extending into the furnace hearth, a stand having an inclined upper surface adapted to support veach skid intermediate the ends thereof, and means for maintaining the upper end of each skid in abutting relation with the furnace hearth with the reinforcing members extendingV into the hearth, and 4closure means extending between and supported by said skids.

14. Apparatus for discharging billets, blooms, bars and the like from a heating furnace having a discharge opening and a hearth spaced therefrom over which the material passes comfor a cooling fluid, means for circulating a cooling `fluidthrough each of said chambers, means for supporting the upper end of each of said skids, `means for supportingjhe skids interrnediate the ends thereo-f, a depending member Carried by each of said skids, and means for maintaining the upper end of each skid in abutting relation with the end of the furnace hearth.

l5. Apparatus for discharging billets, blooms, bars and the like from a heating furnace having a `discharge opening and a hearth `spaced therefrom over which the material passes comprising a plurality of spaced skids/extending ldownwardly at an .angle from the furnace hearth i of `each of said skids and adapted to extend into the hearth, means for supporting said skids, and

means for maintaining the upper endof each skid in abutting relation with the` end of the hearth and said plates within the hearth.

16. Apparatus for discharging billets, blooms,- bars and the like from a heating furnace having a "discharge opening and a hearthspaced therefrom over which the material passes comprising a plurality of spaced, substantially parallel skids extending downwardly at an angle from the hearthto the discharge opening, each skid` having bottom, top. side and end walls united to-` gether to form a chamber for a cooling iiuid,` means for circuating a cooling fiuid through each of said skids from the lower end to the upper end thereof, means for supporting the` upper end fof each of said skids adjacent the end of said hearth, meansfor supporting `the `skids intermediate the ends thereof, and ,means cooperating with each of said skidsvfor maintaining the upper ends thereof tightly against the end of said furnace hearth.

17. Apparatus for discharging billets, blooms, bars and the like froma heating furnace having a hearth over which the material passes `comprising a plurality of spaced, substantially parallel skids, each skid having bottom, top, side and end plates united together to forni a chamber fora cooling fluid, means for supplying a cooling fluid to each of said skids adjacent one end thereof, means for discharging cooling iiuid from each of said chambers at the end thereof adjacent the furnace hearth, and means for supporting each of said skids and for maintaining the discharge end thereof in `abutting relation with the end of said furnace hearth.

JULIUS H. S'IRASSBURGER.