US2194977A - Annealing apparatus - Google Patents
Annealing apparatus Download PDFInfo
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- US2194977A US2194977A US166430A US16643037A US2194977A US 2194977 A US2194977 A US 2194977A US 166430 A US166430 A US 166430A US 16643037 A US16643037 A US 16643037A US 2194977 A US2194977 A US 2194977A
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- Prior art keywords
- hood
- base
- partitions
- annealing
- openings
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
Definitions
- the present invention relates generally to annealing apparatus, and is a continuation in part of my co-pending application Serial No. 66,932, filed March 3, 1936, and entitled Annealing furnace structure, and relates particularly to the heat treating of sheet steel and tin in a manner insuring proper'distribution of the heat to the top, bottom and sides of the material during the treatment, and in a manner to positively prevent oxidizing of the material under treatment; and an important object of the present invention is to provide annealing structure of the character indicated wherein the construction may be sectional or integral so as to' facilitate the handling of the furnace itself and its emciency in operation.
- Another important object of the present invention is to provide annealing apparatus oi the character indicated wherein portions thereof are portable to increase the mobility and utility in increasing the productivity thereof.
- Another important object of the present invention is to provide improvements in structure and function over the subject matter contained in the mentioned pending application, in the respects of more efiicient circulation of and use of the heating gases and products of combustion, in the adjustability of the partitions forming the combination and annealing chambers, respectively, whereby by a simple adjustment the flow of the heating gases may be changed in accordance with requirements.
- Another important object of the present invention is to provide improvements over the subject matter of the said pending application, in the respects of greater accessibility and simplicity of manufacture and operation of the furnaces.
- Figure 1 is a side elevational viewof a form of the invention which is generally elongated rectangular in plan and is provided with a hood having straight vertical longitudinal walls and straight squared end walls terminating at their upper edges in a relatively slightly curved top which curves from side to side, upper and lower rows of burner openings being provided for alternate use in the opposite longitudinal sides of this embodiment.
- Figure 2 is an end elevational view 01' Figure 1.
- Figure 3 is a view of an embodiment of the invention similar to that shown in Figure l and discusring therefrom only by reason of the provision of removable straps extending between the base and the hood and enabling transporting the furnace combination of hood and base from place to place as may be needed.
- Figure 4 is an enlarged horizontal sectional view taken through Figure" 1 approximately on the line 5-4 and looking downwardly in the di- 31g; rection of the arrows. 1 4
- Figure 5 is an enlarged transverse vertical sectional view taken through Figure l approximately on the line 5-5.
- Figure 6 is a fragmentary view similar to Figure 5 but showing the hood raised from the base.
- Figure 7 is a fragmentary view similar to Figure 6 but showing the partitions in raised adjusted positions, these partitions being shown in depressed positions in Figure 5.
- Figure 8 is a group horizontal sectional view taken through a portion of one of the partitions showing the solid elements composing the same.
- the numeral 5 generally designates the hood of the furnace which may have an arch-shaped cross section as shown or assume any other suitable size and shape and be composed of an outer metal shell 6 having a hoisting handle at the middle of its top.
- the lower edge of the shell has a laterally inwardly extending flange 8 which rests on a similar flange 8' on the upper edge of the peripheral wall on the base I ll so that the hood 'is thereby separably assembled on the base and may be lifted therefrom.
- the hood may be connected to the base in some suitable manner such as indicated in Figure 3 of the drawings whereby the base is lifted along with the hood.
- Upper and lower burner openings H are distributed along the sidewalls of the hood, any suitable number of burner openings being provided according to requirements.
- the hood has its interior lined with suitable refractory material structure, the walls of which are severally and respectively designated by the numerals l3, l4, I5 and it.
- the present furnace shows two partitions l1, I1 which are spaced from the sidewalls IS, IS, respectively, and extend between the end walls l3, ll of the hood, thereby defining the combustion chambers, and the annealing chamber betweenthe partitions.
- Each partition is composed of a number of tiers exemplified by the vertically succeeding sections ll, IO and I. and 25' supporting rod in each tier, and a desirable number of tiers is used in each partition II, the tiers being juxtaposed and interlocked in a manner to be pointed out.
- Each tier section is of heat resisting metal or or refractory material suitable to radiate and conduct heat from the combustion chamber to the material being heated, and constituted by a triangular cross section body 2
- One end of the annealing chamber wall l5 of each of the sections is pointed as indicated by the numeral 35 while at the opposite end the adjoining side wall of the section is notched as indicated by the numeral 36, both formations extending the full height of the respective section.
- the points 35 are engaged with the notches 36 in juxtaposing and assembling the various tiers of sections to form the respective partitions II.
- the bottom of the lowermost sections are squared to stand squarely on the base when the partitions are lowered, while the upper ends of the uppermost tier sections are angulated to conformably engage the top of the hood when the partitions are elevated.
- the base i0 has within the annealing chamber defined by the end walls l3 and I4 and the partitions H has thereon the longitudinally arranged annealing stands 40 and 4
- Any suitable number of stands may be used with corresponding obvious rearrangements and enlargements of the base and hood structure described.
- is composed of suitable material in the form of a plate 42 from which depend conical legs 43 which space the plate .42 above the floor of the base and permit free circulation of the gases under the plate 42.
- each stand Imposed on each stand is the respective cover 44, 45 enclosing a respective stack (not shown) of the sheet material being treated and annealed, wherein each cover is provided on its sides with downwardly tapering flanges 48 which have attached to the outer lower edge thereof the sand retaining rim 49 which retains a quantity of sand or the like to prevent passage of any air or fluid between the top of the stand and the interior of the cover, thereby preventing the-possibility of any oxidizing of the contents of the cover.
- the base comprises a shallow pan-shaped shell whose floor, end walls and sidewalls are lined with refractory material, the lower halves of the lower burner openings being formed in the upper edges of the sidewalls.
- the tier forming sections of the partitions are provided with a vertical bore 22 to receive the 55 which has on its lower end a head 56 socketing in the lowermost section of the respective tier and having its upper end threaded as indicated by the numeral 51 and passing through a tube 58 in the transversely curved hood 5 on the top of which a nut 59 is threaded on the threaded portion 58 in the manner disclosed in Figure 5.
- the topmost sections of the tiers are beveled as indicated by the numeral 55 to conform to the contour of the inner surface of the curved top of the hood to provide a gas passage there while the lower ends of the tiers are resting on the floor of the base II.
- the longitudinal side walls l5 and II of the hood are provided with horizontal rows of upper burner openings 64 and 65. Below these rowsof burner openings are the burner openings ii which are half in the base and half in the lower edge of the hood 5.
- the exhaust openings are arranged in three rows through the base, one row being between the stands 40 and 4
- the plugs 66 and 61 are placed in the upper burner openings 54 and 65 when the partitions are in the depressed positions shown in Figure 11. In the elevated positions of the partitions the burners are shifted to theelevated openings 84 and 65 and the plugs 65 and 51 shifted to the lower burner openings l I to plug the same.
- Figure 6 of the drawings graphically shows the various positions of the parts when the hood 5 is raised from the base 10 with the parti- Figure 3 differs from that shown in Figure 1 only by the provision of straps II which are secured by removable bolts H to the hood and to the base, for connecting the hood and base together to be transported as a unit.
- Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upper and lower rows of burner openings in two opposite side walls only of said hood, plugs for shutting oif either the upper or lower ,row of burner openings while the other row isin use, a vertically adjustable partition adjacent each of said opposite side walls of the hood and dividing the space defined by the interior of the hood and the top of the base into a single centralized annealing chamber between the partitions and two combustion chambers running along the opposite sides of the apparatus, said partitions being vertically adjustable to space the same from the hood or the base in accordance with the row of burner openings in use,
- Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upper and lower rows of burner openings in two opposite side walls only of said hood, plugs for shutting oi! either the upper or lower row 0! burner openings while the other row is in use, a partition adjacent each of said opposite side walls of the hood and dividing the space defined by the interior of the hood and the top'ofthe base into a single annealing chamber located.
- partitions are shorter than the distance between the base and the top of the hood, and means suspending the partitions from the top of the hood and enabling adjusting the partitions to rest on the base or engage the top of the hood.
- Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upperand lower rows of burner openings in the longitudinal side walls only of said hood, plugs for shutting ofleither the upper or lower row of burner openings while the other row is in use, a longitudinal partition adjacent each side wall of the hood and dividing the space defined by the interior of the hood and the top 01 the base into a single annealing chamber located between the partitlons and two combustion chambers running along the opposite sides of the apparatus, the up-.
- the partitions per ends of the partitions being spaced below the top of the hood, the lower row of burner openings being open and the upper row closed by the plugs, and means suspending, the partitions i'rom the top of the hood and enabling adjusting the partitions to engage the to of the hood and be spaced at their lower ends from the base.
- Annealing apparatus comprising a base formed with exhaust openings, a removable hood resting on the base, longitudinally extending vertical partitions at opposite sides of the hood and dividing the space defined by the hood and base into a centralized annealing chamber and two combustion chambers, said exhaust openings two combustion chambers, said exhaust openings traversing the floor of said annealing chamber, rods depending from said hood and traversing said partitions and holding said partitions in place, the longitudinal side walls of said hood being formed with upper and lower rows of individually closable burner openings, means on said hood for adjusting said rods to permit the lower end of the partitions to rest upon said base or to engage the upper end of the partitions with the top of the hood.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Description
March 1940- c. B. HOAK 2,194,977
ANNEALING APPARATUS Filed Sept. 29; 1957 4 Sheets-Sheet 1 Man}! 1940- c. B. HOAK 2,194,977
Y ANNEALING APPARATUS Filed Sept. 29, 1937 4 Sheets-Sheet 2 /4 I Inventor Attorneys 7 March 26, 1940. c. B. HOAK ANNEALING APPARATUS Filed Sept. 29, 1937 4 Sheets-Sheet 3 March 26, 1940. c. B. HOAK 2,194,977
ANNEALING APPARATUS v 1 Filed Sept. 29, 1937 4 Sheets-Sheet 4 9 39 I 9 Inventor A iior rzeys Patented M... as, 1940 UNITED STATES PATENT OFFICE ANNEALING APPARATUS Clarence B. Hoak, Steubenville, Ohio Application September 29, 1937, Serial No. 166,439
5 Claims.
The present invention relates generally to annealing apparatus, and is a continuation in part of my co-pending application Serial No. 66,932, filed March 3, 1936, and entitled Annealing furnace structure, and relates particularly to the heat treating of sheet steel and tin in a manner insuring proper'distribution of the heat to the top, bottom and sides of the material during the treatment, and in a manner to positively prevent oxidizing of the material under treatment; and an important object of the present invention is to provide annealing structure of the character indicated wherein the construction may be sectional or integral so as to' facilitate the handling of the furnace itself and its emciency in operation.
Another important object of the present invention is to provide annealing apparatus oi the character indicated wherein portions thereof are portable to increase the mobility and utility in increasing the productivity thereof.
Another important object of the present invention is to provide improvements in structure and function over the subject matter contained in the mentioned pending application, in the respects of more efiicient circulation of and use of the heating gases and products of combustion, in the adjustability of the partitions forming the combination and annealing chambers, respectively, whereby by a simple adjustment the flow of the heating gases may be changed in accordance with requirements.
Another important object of the present invention is to provide improvements over the subject matter of the said pending application, in the respects of greater accessibility and simplicity of manufacture and operation of the furnaces.
Other important objects of the present invention will be apparent from a reading of the following description taken in connection with the drawings, wherein for purposes of illustration I have shown preferred embodiments of the present invention.
In the drawings Figure 1 is a side elevational viewof a form of the invention which is generally elongated rectangular in plan and is provided with a hood having straight vertical longitudinal walls and straight squared end walls terminating at their upper edges in a relatively slightly curved top which curves from side to side, upper and lower rows of burner openings being provided for alternate use in the opposite longitudinal sides of this embodiment.
Figure 2 is an end elevational view 01' Figure 1.
Figure 3 is a view of an embodiment of the invention similar to that shown in Figure l and diilering therefrom only by reason of the provision of removable straps extending between the base and the hood and enabling transporting the furnace combination of hood and base from place to place as may be needed.
Figure 4 is an enlarged horizontal sectional view taken through Figure" 1 approximately on the line 5-4 and looking downwardly in the di- 31g; rection of the arrows. 1 4
Figure 5 is an enlarged transverse vertical sectional view taken through Figure l approximately on the line 5-5.
Figure 6 is a fragmentary view similar to Figure 5 but showing the hood raised from the base.
Figure 7 is a fragmentary view similar to Figure 6 but showing the partitions in raised adjusted positions, these partitions being shown in depressed positions in Figure 5.
Figure 8 is a group horizontal sectional view taken through a portion of one of the partitions showing the solid elements composing the same.
Referring in detail to the drawings, the numeral 5 generally designates the hood of the furnace which may have an arch-shaped cross section as shown or assume any other suitable size and shape and be composed of an outer metal shell 6 having a hoisting handle at the middle of its top. The lower edge of the shell has a laterally inwardly extending flange 8 which rests on a similar flange 8' on the upper edge of the peripheral wall on the base I ll so that the hood 'is thereby separably assembled on the base and may be lifted therefrom. In some cases the hood may be connected to the base in some suitable manner such as indicated in Figure 3 of the drawings whereby the base is lifted along with the hood. Upper and lower burner openings H are distributed along the sidewalls of the hood, any suitable number of burner openings being provided according to requirements.
The hood has its interior lined with suitable refractory material structure, the walls of which are severally and respectively designated by the numerals l3, l4, I5 and it.
As illustrated the present furnace shows two partitions l1, I1 which are spaced from the sidewalls IS, IS, respectively, and extend between the end walls l3, ll of the hood, thereby defining the combustion chambers, and the annealing chamber betweenthe partitions.
Each partition is composed of a number of tiers exemplified by the vertically succeeding sections ll, IO and I. and 25' supporting rod in each tier, and a desirable number of tiers is used in each partition II, the tiers being juxtaposed and interlocked in a manner to be pointed out.
Each tier section is of heat resisting metal or or refractory material suitable to radiate and conduct heat from the combustion chamber to the material being heated, and constituted by a triangular cross section body 2|.
One end of the annealing chamber wall l5 of each of the sections is pointed as indicated by the numeral 35 while at the opposite end the adjoining side wall of the section is notched as indicated by the numeral 36, both formations extending the full height of the respective section. The points 35 are engaged with the notches 36 in juxtaposing and assembling the various tiers of sections to form the respective partitions II. The bottom of the lowermost sections are squared to stand squarely on the base when the partitions are lowered, while the upper ends of the uppermost tier sections are angulated to conformably engage the top of the hood when the partitions are elevated.
The base i0 has within the annealing chamber defined by the end walls l3 and I4 and the partitions H has thereon the longitudinally arranged annealing stands 40 and 4| between which is arranged a row of vertical exhaust outlet openings 39 with similar rows of exhaust openings at the outer sides of the stands adjacent the partitions as indicated. ,Any suitable number of stands may be used with corresponding obvious rearrangements and enlargements of the base and hood structure described. Each annealing stand or platform 40, 4| is composed of suitable material in the form of a plate 42 from which depend conical legs 43 which space the plate .42 above the floor of the base and permit free circulation of the gases under the plate 42.
Imposed on each stand is the respective cover 44, 45 enclosing a respective stack (not shown) of the sheet material being treated and annealed, wherein each cover is provided on its sides with downwardly tapering flanges 48 which have attached to the outer lower edge thereof the sand retaining rim 49 which retains a quantity of sand or the like to prevent passage of any air or fluid between the top of the stand and the interior of the cover, thereby preventing the-possibility of any oxidizing of the contents of the cover.
Attention is called to the fact that the line of separation between the hood and the base is on a level which passes through lower side wall burner openings which are located above the floor level of the base, so that the burners may be attached either to the upper or hood half of the burner opening or to the lower or base half of the burner opening as may be found desirable. The base comprises a shallow pan-shaped shell whose floor, end walls and sidewalls are lined with refractory material, the lower halves of the lower burner openings being formed in the upper edges of the sidewalls.
The tier forming sections of the partitions are provided with a vertical bore 22 to receive the 55 which has on its lower end a head 56 socketing in the lowermost section of the respective tier and having its upper end threaded as indicated by the numeral 51 and passing through a tube 58 in the transversely curved hood 5 on the top of which a nut 59 is threaded on the threaded portion 58 in the manner disclosed in Figure 5. The topmost sections of the tiers are beveled as indicated by the numeral 55 to conform to the contour of the inner surface of the curved top of the hood to provide a gas passage there while the lower ends of the tiers are resting on the floor of the base II.
In the embodiment of the invention shown in Figure 7, all of the structure present in the embodiment already described is present in the same, the only difference between Figure 5 and Figure '7 being the adjustment on the partition H to an elevated instead of a depressed position and the provision of a spacing sleeve 5! resting on the top of the tuber and engaged at its upper end by the nut 59 so as to bring the beveled top 50 of the tier to engagement with the top of the furnace hood and to bring the lower end 6| of the tier into vertically spaced relation with the floor of the base so as to define a gas passage.
The longitudinal side walls l5 and II of the hood are provided with horizontal rows of upper burner openings 64 and 65. Below these rowsof burner openings are the burner openings ii which are half in the base and half in the lower edge of the hood 5. The exhaust openings are arranged in three rows through the base, one row being between the stands 40 and 4| and the others being at the laterally outward sides of the stands and between them and the partitions II. The plugs 66 and 61 are placed in the upper burner openings 54 and 65 when the partitions are in the depressed positions shown in Figure 11. In the elevated positions of the partitions the burners are shifted to theelevated openings 84 and 65 and the plugs 65 and 51 shifted to the lower burner openings l I to plug the same.
Figure 6 of the drawings graphically shows the various positions of the parts when the hood 5 is raised from the base 10 with the parti- Figure 3 differs from that shown in Figure 1 only by the provision of straps II which are secured by removable bolts H to the hood and to the base, for connecting the hood and base together to be transported as a unit.
Although I have shown and described herein preferred embodiments of, my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in the materials and in the structure and arrangement of the parts, within the spirit of the invention and the scope of the subjoined claims.
Having described the invention, what is claimed as new is:
1. Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upper and lower rows of burner openings in two opposite side walls only of said hood, plugs for shutting oif either the upper or lower ,row of burner openings while the other row isin use, a vertically adjustable partition adjacent each of said opposite side walls of the hood and dividing the space defined by the interior of the hood and the top of the base into a single centralized annealing chamber between the partitions and two combustion chambers running along the opposite sides of the apparatus, said partitions being vertically adjustable to space the same from the hood or the base in accordance with the row of burner openings in use,
2. Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upper and lower rows of burner openings in two opposite side walls only of said hood, plugs for shutting oi! either the upper or lower row 0! burner openings while the other row is in use, a partition adjacent each of said opposite side walls of the hood and dividing the space defined by the interior of the hood and the top'ofthe base into a single annealing chamber located. between the partitions and two combustion chambers running along the opposite sides of the apparatus, said partitions being shorter than the distance between the base and the top of the hood, and means suspending the partitions from the top of the hood and enabling adjusting the partitions to rest on the base or engage the top of the hood.
3. Annealing apparatus comprising a generally rectangular base, a similarly rectangular hood resting on and enclosing said base, upperand lower rows of burner openings in the longitudinal side walls only of said hood, plugs for shutting ofleither the upper or lower row of burner openings while the other row is in use, a longitudinal partition adjacent each side wall of the hood and dividing the space defined by the interior of the hood and the top 01 the base into a single annealing chamber located between the partitlons and two combustion chambers running along the opposite sides of the apparatus, the up-. per ends of the partitions being spaced below the top of the hood, the lower row of burner openings being open and the upper row closed by the plugs, and means suspending, the partitions i'rom the top of the hood and enabling adjusting the partitions to engage the to of the hood and be spaced at their lower ends from the base.
4. Annealing apparatus comprising a base formed with exhaust openings, a removable hood resting on the base, longitudinally extending vertical partitions at opposite sides of the hood and dividing the space defined by the hood and base into a centralized annealing chamber and two combustion chambers, said exhaust openings two combustion chambers, said exhaust openings traversing the floor of said annealing chamber, rods depending from said hood and traversing said partitions and holding said partitions in place, the longitudinal side walls of said hood being formed with upper and lower rows of individually closable burner openings, means on said hood for adjusting said rods to permit the lower end of the partitions to rest upon said base or to engage the upper end of the partitions with the top of the hood. 1
CLARENCE B. HOAK.,
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US166430A US2194977A (en) | 1937-09-29 | 1937-09-29 | Annealing apparatus |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US166430A US2194977A (en) | 1937-09-29 | 1937-09-29 | Annealing apparatus |
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US2194977A true US2194977A (en) | 1940-03-26 |
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US166430A Expired - Lifetime US2194977A (en) | 1937-09-29 | 1937-09-29 | Annealing apparatus |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2436024A (en) * | 1942-01-20 | 1948-02-17 | Continental Steel Corp | Annealing furnace |
US2480374A (en) * | 1945-09-20 | 1949-08-30 | Carnegie Illinois Steel Corp | Furnace |
-
1937
- 1937-09-29 US US166430A patent/US2194977A/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2436024A (en) * | 1942-01-20 | 1948-02-17 | Continental Steel Corp | Annealing furnace |
US2480374A (en) * | 1945-09-20 | 1949-08-30 | Carnegie Illinois Steel Corp | Furnace |
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