US1173590A - Heat-treating apparatus. - Google Patents

Heat-treating apparatus. Download PDF

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Publication number
US1173590A
US1173590A US5048515A US5048515A US1173590A US 1173590 A US1173590 A US 1173590A US 5048515 A US5048515 A US 5048515A US 5048515 A US5048515 A US 5048515A US 1173590 A US1173590 A US 1173590A
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furnace
floor
roof
treating apparatus
chamber
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US5048515A
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John J Lichter
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St Louis Frog & Switch Co
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St Louis Frog & Switch Co
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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0062Heat-treating apparatus with a cooling or quenching zone

Definitions

  • This invention relates to heat treating 'apparatus, and is an improvement on the heat treating.
  • apparatus described in my prior U. S. Patent No. 1,112,074, dated Sep- Oneobject of my present invention is to provide a heat treating apparatus in which the entire quenching bath is located directly beneath the furnace chamber and is com-- pletely cut'ofi from the atmosphere when the material bein' and quenched, th reby eliminating the possibility of the material being exposed to the atmosphere, and thus cooling off or oxidizing while it is being conveyed from the furnace chamber to the quenching bath, and
  • FIG. 2 is a vertical transverse sectional view taken on the line 2'-2 of Fig. 1; and Fig. 3 is ahorizontal sectional view taken Referring to the drawings which illus strate the preferred form of my invention,
  • A designates a furnaceof-substantially oblong shape in outline that is arranged "di-' rectly over a dippingtank B which contains' a quenching bath in which the mate rial being treated is dipped, after said materialhas been, heated to a predetermined temperature in the furnace
  • the furnace A'and dipping tank Binay be of any preferred construction, but I prefer to build the vertical walls of the furnace A upon the verticalwallsv of the dipping-tank B, so that said tank will act'as afoundation for the furnace and will be of the same shape or outline as the furnace.
  • the side and end walls of the furnace A are provided with sight openings 1 and any suit able means may be employed for heating said furnace.
  • burners 2 arearranged' at one side of the furnace in ahmeld with inlet ports 3 in one of the vertical side walls of the furnace, the opposite side wall being provided with waste 2'5 flues 4 that lead to a horizontallvdisposed flue 5 which co1nmunicates' with a stack (not shown).
  • the top or roof C of the furnace A is flat, as shown in Figs. 1 and 2, and the waste fines 4 extend throughout the entire length of the furnace so that the heat wil be distributeduniformly and evenly throughout. 7 the entire length and width i the'furnace chamber D."
  • i T I The bottom or fl001'-"15 -of the furnace A is formed of refractory material and it is so arranged that it can be raised and loweredinto and out of the quenching bath and also mo tjed upwardly through the furnace chamber D.
  • the top 'or roof C of the furnace is IGIHOV".
  • the material being treated can i can be constructed in various l p V be introduced into the furnace and removed therefrom, thereby overcoming the necessity of forming doors in the vertical walls of the Ways, but I prefer to mount said root on a movable supporting structure that travels on tracks, so as to enable the root to be moved easily into and out of operative position.
  • the movable supporting structure that carries the roof is composed of two end frames F arranged outside of the end Walls of the furnace A and connected to gether by girders 6 that extend longitudinallyof the furnace.
  • Cross members T that are connected to the girders 6 carry longi tudinally-disposed members 8, preferably I-beams, which support tiles 9 that term the roof or top C of the furnace chamber.
  • Said tile top or root is surrounded by a rectangular shaped frame 10, preferably built up of channel irons, and connected to the longitudinal girder 6, as shown in Figs. 1 and 2.
  • a rectangular shaped frame 10 preferably built up of channel irons, and connected to the longitudinal girder 6, as shown in Figs. 1 and 2.
  • the end frames F are provided with wheels 12 that travel on tracks 12 and means are provided for raising and lowering said end frames so that the top C will clear the vertical Walls of the furnace A when said top is being moved into and out of operative position.
  • the vertical movement frames F can be effected in various ways,
  • one of the wheels 12 can be provided with a gear 12, as sho wn in F 2, that meshes with a pinion 16 that forms part of a manuallyoperahle driving; mechanism that comprises a crank '17, thereby enabling the root C to be moved laterally away from the furnace A by a single workman, after said roof has been raised suiliciently to clear the vertical walls of the furnace.
  • the floor or bottom ll of the furnace A is carried by an elevator or vertically-nuivable supporting structure (l, which may be of any preferred type, the one herein shown being built up of commercially rolled momof the end r hers, such, for example, as'angle irons, channels and ill-beams, and being of sullicient height so that it will rest upon supporting devices 18, hereinafter described, when the floor E at its upper limit oi moven'ient, namely, flush. 0' approximately flush, with the upper edges of the vertical walls of the furnace A.
  • the structure U is equipped with two horizontally-disposed shafts 15), shown in Fig.
  • the structure it that carries the floor E of the furnace is provided with four pinions that mesh with four verticallysdisposed rack bars, said pinions being geared together in such a n'lanner that all of the pinions will move in unison, and thus hold the floor E level, irrespective of whether the load on one end of the door is greater than the load on the other end.
  • a hydraulic means consisting at a stationary piston 23' that pro ects into a 'inovable cylinder'ilt that projects, down- ,wardly from the structure (l, as shown in Fig. l, the motive fluid being supplied to the cylinder 2% by means of a pipe flfithat conurmmcates with a duct in the stationary piston 23.
  • the floor E of the furnace is arranged in the position shown in Fig. 1, said floor being held securely in this position by means of the supporting devices 18, previously referred to, which coiiperate with abutmcnts 1b on the structure G that carries said iloor.
  • the supporting devires'lti are moved into an inoperative position and the Stllltltlll't! (l is then moved downwardly into the position shown in Fig.
  • the structure Gthat carriessaidfloor is moved .v downwardly into the position shown in Fig. l 1, :and the top 0 of thefurnace is thereafter moved back to its operative position.
  • the supporting devices 18 that hold the floor E of the furnace in position while the material is being heated and while the material is beingremoved from the furnace andintroduced into the furnace eonsi'st of arms" on" rock shafts 26 journaled in the end walls of the dipping tank B and p ovided with operating handles 27,' shown' in b course, it will be understood that various other means" could be employed for sustaining the weight of that element of the appa- 30 ratus 'which supports the material being ployed for raising and lowering the member that supports the material being treated.
  • the entire quenching bath is located directly beneath the furnace chamber and forms a liquid seal for the furnace 'chamber. Consequently, there is no possibility of the materialzcooling off or oxidizing when it is being conveyed fromlthe furnace chamber to the quenching bath, owing] to the .fact that the material passes directly from the furnace chamber 'intothe quenching bath Without being exposed to the atmosphere and without coming in contact with air which is at a lower temperature than the air in the furnace chamber and the air at the surface of the quenching bath.
  • a dipping tank completely cut ⁇ off from the atmosphere whenthe'furnace heat-treating apparatus, comprising a heating furnace provided with a removiis in operation and containinga quenching.
  • Aheat treating apparatus' comprisin gi a dipping tank that is adapted to contain. a quenching bath, a heating furnace whose vertical walls form continuations of the veff tical walls of said dipping tank, a removable roof or top for said furnace, andmeans for supporting the material that, is to be treated,
  • saidmeans being adapted to be immersed in the quenching bath in said tank.
  • a heat treating apparatus comprising"- a heating furnace, a dipping tank arranged under said furnace for holding a quenching bath that is completely out off from the atmosphere when the furnace is i'n-operation, a' removable top or roof for said r furnace, a traveling structure that carries said roof, a floor for said furnace that holds the material being treated, and means for lowering and raising said floor so as to im- ,mersc the material thereon in the quenching bath andlthercafter move the floor upwardly through the chamber of the furnace into such a position that the material on said floor can-be'itakenout of thefurnace' through the opening that the top or roof closes.
  • l V L 4 comprising a heating furnace, a dipping tank arranged v i under said furnace for holding a quenching bath, a1flat roof forjsaid furnace, a
  • traveling structure that carries said roof, means for raising! and lowering 'said. roof so that it willclear the vertical walls of the furnace when the roof is being moved into and outof operative position, and a vertically movable floor for said furnace that holds the material being treated, said floor being adapted. to be moved downwardly into the quenching bath and thereafter upwardly throu h the furnace. chamber into such a POSltlOILtllfll; the material through the opening at the upper end of the furnace chamber that the roof closes when said roof isin operative position.
  • a heat "treating apparatus comprising on the floor can be removed therefrom I a heatin funmceprovided with a removmble fiat rooi, n dipping tank arranged under said furnace and adapted to contain a qumlching bath, Waste fines at one side of the furnace that extend throughout the entire length of same, mans arranged at the apposite side 0f tin furnace for causing fire gases to pass transversely across the furnace'clmmber, and a vertically movable structure in said dipping tank that carries 10 a refractory floor for said furnace chamber.

Description

J. JQ LIGHTER.
HEAT'THEATING APPARATUS.
APPLICATION FlLED SEPT-13.19%.
1,32%,599. I Patented Feb. 19m.
2 SHEETS-SHEET I.
Jae/ea); I
J. 1. LIGHTER. HEAT TREATING APPARATUfi. I APPLICATION FILED SEPT. 13. 3915.
Patented Feb. 29, 1916 2 SHEETS---SHEET 2- STATES PATENT; OF ICE; a I
JOHN .T
LIGHTER, OF ST. LOUTS, MISSOURI ASSIGNOR.TO ST. LOUIS FROG &. SWITCH COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.
HEATJIREATING ArranA'rUs.
pertains to make and use the same.
tember 29,1914.
This invention relates to heat treating 'apparatus, and is an improvement on the heat treating. apparatus described in my prior U. S. Patent No. 1,112,074, dated Sep- Oneobject of my present inventionis to provide a heat treating apparatus in which the entire quenching bath is located directly beneath the furnace chamber and is com-- pletely cut'ofi from the atmosphere when the material bein' and quenched, th reby eliminating the possibility of the material being exposed to the atmosphere, and thus cooling off or oxidizing while it is being conveyed from the furnace chamber to the quenching bath, and
also overcoming the necessity of sealing the joints between the side walls of the furnace chamber and the movable member that supports the material Another Ob]i is to provide a heat treating apparatus that comprises a furnace which is provided with a removable top-or roof and. a vertically movable floor that is adapted to be moved upwardly through the furnace chamber into a position toieceive the material being treated, and ti" =-:l6tfi161' lowered into a dipping tank that is arranged under the furnace, the top of the furnace being constructed in such a manner that it can be removed easily When the ma: .teria-lis being introduced into the furnace. or
removed therefrom, and thereafter replaced in operative position on the vertical walls of the furnace. And still another object is to provide a heat treating apparatus. in wlt'wh the vertically movable element that supports the material. while it is being heated and quenched is so constructed that there is no. possibility of said element binding or not moving freely in case the mate rial is not loaded on same evenly.
Other objects and desirable features of my invention will be hereinafter pointed out.
3 Figure 1. of the drawings isavertical Specification of Letters Patent.
on the line 3-3 of Fig. 2. such as Willen- I treated is being heated furnace. The roof (3 Patented Feb. 29, 1916.
Application filed September 1?", 1915. Serial No. 50,485.
longitudinal sectional view of an apparatus constructed in accordance with my i'nven tion. :Fig. 2 is a vertical transverse sectional view taken on the line 2'-2 of Fig. 1; and Fig. 3 is ahorizontal sectional view taken Referring to the drawings which illus strate the preferred form of my invention,
A designates a furnaceof-substantially oblong shape in outline that is arranged "di-' rectly over a dippingtank B which contains' a quenching bath in which the mate rial being treated is dipped, after said materialhas been, heated to a predetermined temperature in the furnace The furnace A'and dipping tank Binay be of any preferred construction, but I prefer to build the vertical walls of the furnace A upon the verticalwallsv of the dipping-tank B, so that said tank will act'as afoundation for the furnace and will be of the same shape or outline as the furnace.
The side and end walls of the furnace A are provided with sight openings 1 and any suit able means may be employed for heating said furnace. I I
In the apparatus herein shown burners 2 arearranged' at one side of the furnace in ahnement with inlet ports 3 in one of the vertical side walls of the furnace, the opposite side wall being provided with waste 2'5 flues 4 that lead to a horizontallvdisposed flue 5 which co1nmunicates' with a stack (not shown).
The top or roof C of the furnace A is flat, as shown in Figs. 1 and 2, and the waste fines 4 extend throughout the entire length of the furnace so that the heat wil be distributeduniformly and evenly throughout. 7 the entire length and width i the'furnace chamber D." i T I The bottom or fl001'-"15 -of the furnace A is formed of refractory material and it is so arranged that it can be raised and loweredinto and out of the quenching bath and also mo tjed upwardly through the furnace chamber D.
The top 'or roof C of the furnace is IGIHOV".
able, so that the material being treated can i can be constructed in various l p V be introduced into the furnace and removed therefrom, thereby overcoming the necessity of forming doors in the vertical walls of the Ways, but I prefer to mount said root on a movable supporting structure that travels on tracks, so as to enable the root to be moved easily into and out of operative position. In the form of my invention herein illustrated the movable supporting structure that carries the roof is composed of two end frames F arranged outside of the end Walls of the furnace A and connected to gether by girders 6 that extend longitudinallyof the furnace. Cross members T that are connected to the girders 6 carry longi tudinally-disposed members 8, preferably I-beams, which support tiles 9 that term the roof or top C of the furnace chamber. Said tile top or root is surrounded by a rectangular shaped frame 10, preferably built up of channel irons, and connected to the longitudinal girder 6, as shown in Figs. 1 and 2. "When the roof C is in operative position, as shown in Fig: 1, said rectangular shaped frame 10 rests upon metal top plates 11 on the vertical walls 0t the furnace A. The end frames F are provided with wheels 12 that travel on tracks 12 and means are provided for raising and lowering said end frames so that the top C will clear the vertical Walls of the furnace A when said top is being moved into and out of operative position. The vertical movement frames F can be effected in various ways,
but I prefer to construct said end frames in the manner shown in Fig. 2, wherein it will be seen that the wheels 12 are journalcdin the outer ends of levers 13 whose inner ends are pivotally connected to operating rods 14: which can be moved upwardly and downwardly by means of operating Wheels 15 that have internally screw-threaded bores through which externally screw-threzulcd portions on the rods 14a pass. By turning the wheels 15 in one direction the inner ends of the lovers 13 will be moved upwardly, thereby raising the endirames F, owing to the fact that said end frames are carried by said lovers, and .by rotating said wheels 15 in the opposite direction, said end .frames will be lowered, it, of course, being understood that the end frames are raised preparatory to moving the roof (1 into inoperative position, asillustrated in Fig. If desired, one of the wheels 12 can be provided with a gear 12, as sho wn in F 2, that meshes with a pinion 16 that forms part of a manuallyoperahle driving; mechanism that comprises a crank '17, thereby enabling the root C to be moved laterally away from the furnace A by a single workman, after said roof has been raised suiliciently to clear the vertical walls of the furnace.
The floor or bottom ll of the furnace A is carried by an elevator or vertically-nuivable supporting structure (l, which may be of any preferred type, the one herein shown being built up of commercially rolled momof the end r hers, such, for example, as'angle irons, channels and ill-beams, and being of sullicient height so that it will rest upon supporting devices 18, hereinafter described, when the floor E at its upper limit oi moven'ient, namely, flush. 0' approximately flush, with the upper edges of the vertical walls of the furnace A. The structure U is equipped with two horizontally-disposed shafts 15), shown in Fig. that are provided with pinions 19'' which mesh with verticallydisposed racks 20 mounted on the side walls of the dipping tank B, and said shafts 19 are connected with one another by means of two cross shafts .21 that are provided with beveled pinions 21 that mesh with beveled pinions 22 on the shafts 12). By guiding the structure G in this manner I eliminate the possibility of said structure binding or not moving freely, in case the material being treated is not loaded on the floor E evenly, owing to the fact that the shafts 1!] are geared together and are provided with pinions that mesh with verticallysdisposed rack bars on the side walls of the dipping tank. In other words, the structure it that carries the floor E of the furnace is provided with four pinions that mesh with four verticallysdisposed rack bars, said pinions being geared together in such a n'lanner that all of the pinions will move in unison, and thus hold the floor E level, irrespective of whether the load on one end of the door is greater than the load on the other end.
Various means may be employed for rais- I ing and lowering the floor IE, but I prefer to use a hydraulic means consisting at a stationary piston 23' that pro ects into a 'inovable cylinder'ilt that projects, down- ,wardly from the structure (l, as shown in Fig. l, the motive fluid being supplied to the cylinder 2% by means of a pipe flfithat conurmmcates with a duct in the stationary piston 23.
Wheuthe material is being heated the floor E of the furnace is arranged in the position shown in Fig. 1, said floor being held securely in this position by means of the supporting devices 18, previously referred to, which coiiperate with abutmcnts 1b on the structure G that carries said iloor. After the u'iaterial on the lloor has been heated to a 1undetermined tenuicrature the supporting devires'lti are moved into an inoperative position and the Stllltltlll't! (l is then moved downwardly into the position shown in Fig. 2,'so that the material on the floor 1) will be innncrsediu the quenching: bath in the dipping tank 13, the structure (i being providcd at its lower end with abutments 15:3 which rest upon stops 18 on the bottom of the dipping tank. when the lloor F is in its lowermost position. After the material has been quenched. "the top 7 of the furnace raised slightly by manipulating the hand. wheels and then movedf loaded from thefloor and fresh material placed thereon, the floor E being-held securely in its elevated position by means of the supporting devices'18 which then cooperate with the abutments 18 at ,the loweiend of the structure G. 'After the fresh material has been placed on the floor E, the structure Gthat carriessaidfloor is moved .v downwardly into the position shown in Fig. l 1, :and the top 0 of thefurnace is thereafter moved back to its operative position. In the apparatus herein shown the supporting devices 18 that hold the floor E of the furnace in position while the material is being heated and while the material is beingremoved from the furnace andintroduced into the furnace eonsi'st of arms" on" rock shafts 26 journaled in the end walls of the dipping tank B and p ovided with operating handles 27,' shown' in b course, it will be understood that various other means" could be employed for sustaining the weight of that element of the appa- 30 ratus 'which supports the material being ployed for raising and lowering the member that supports the material being treated.
In an apparatusof the construction above described the entire quenching bath is located directly beneath the furnace chamber and forms a liquid seal for the furnace 'chamber. Consequently, there is no possibility of the materialzcooling off or oxidizing when it is being conveyed fromlthe furnace chamber to the quenching bath, owing] to the .fact that the material passes directly from the furnace chamber 'intothe quenching bath Without being exposed to the atmosphere and without coming in contact with air which is at a lower temperature than the air in the furnace chamber and the air at the surface of the quenching bath. The treated material cam be removed quickly'from troduced into the furnace quickly, owing to the fact that the vertical walls of the furnace are 'not provided with 'dbors which have to be sealed, and :the removable top of the furnace is og sufiicient weight to make sealing unnecessary; and still another advantage of such an apparatus is that there is no liability of the elevator or verticallyl movable structure G that carries. the floor 'roken lines in Fig. l, but, of
treated. Furthermore, while Iprefer to use.
the furnace and fresh material can be inr 9f the furnace binding lor not moving ma unease the material is'not loaded with uni?" form distribution of weighton the floor'E Having thus described my invention, what 7 I claim, and desire to secure by Letters Patent, is: "1'. A
moved, and a dipping tank completely cut} off from the atmosphere whenthe'furnace heat-treating apparatus, comprising a heating furnace provided with a removiis in operation and containinga quenching.
bath which acts as a liquid seal for the fur-I nace chamber.
2. Aheat treating apparatus' comprisin gi a dipping tank that is adapted to contain. a quenching bath, a heating furnace whose vertical walls form continuations of the veff tical walls of said dipping tank, a removable roof or top for said furnace, andmeans for supporting the material that, is to be treated,
saidmeans being adapted to be immersed in the quenching bath in said tank.
3. A heat treating apparatus comprising"- a heating furnace, a dipping tank arranged under said furnace for holding a quenching bath that is completely out off from the atmosphere when the furnace is i'n-operation, a' removable top or roof for said r furnace, a traveling structure that carries said roof, a floor for said furnace that holds the material being treated, and means for lowering and raising said floor so as to im- ,mersc the material thereon in the quenching bath andlthercafter move the floor upwardly through the chamber of the furnace into such a position that the material on said floor can-be'itakenout of thefurnace' through the opening that the top or roof closes. l V L 4. A' heat treating apparatus comprising a heating furnace, a dipping tank arranged v i under said furnace for holding a quenching bath, a1flat roof forjsaid furnace, a
traveling structure that carries said roof, means for raising! and lowering 'said. roof so that it willclear the vertical walls of the furnace when the roof is being moved into and outof operative position, and a vertically movable floor for said furnace that holds the material being treated, said floor being adapted. to be moved downwardly into the quenching bath and thereafter upwardly throu h the furnace. chamber into such a POSltlOILtllfll; the material through the opening at the upper end of the furnace chamber that the roof closes when said roof isin operative position.
5. A heat "treating apparatus comprising on the floor can be removed therefrom I a heatin funmceprovided with a removmble fiat rooi, n dipping tank arranged under said furnace and adapted to contain a qumlching bath, Waste fines at one side of the furnace that extend throughout the entire length of same, mans arranged at the apposite side 0f tin furnace for causing fire gases to pass transversely across the furnace'clmmber, and a vertically movable structure in said dipping tank that carries 10 a refractory floor for said furnace chamber. In testimony whereof I hereunto nflix my signature in the, presence of two witnesses, this tenth day of September 1915.
JOHN J. LIGHTER.
Witnesses:
WELLS; L. CHURGII,
GEORGE BAKI2\\ELI.-.
US5048515A 1915-09-13 1915-09-13 Heat-treating apparatus. Expired - Lifetime US1173590A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2458084A (en) * 1941-12-09 1949-01-04 Lee Jess Max Heat-treating system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2458084A (en) * 1941-12-09 1949-01-04 Lee Jess Max Heat-treating system

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