EP0089398B1 - Ceiling beam construction for heating furnace - Google Patents

Ceiling beam construction for heating furnace Download PDF

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Publication number
EP0089398B1
EP0089398B1 EP82102456A EP82102456A EP0089398B1 EP 0089398 B1 EP0089398 B1 EP 0089398B1 EP 82102456 A EP82102456 A EP 82102456A EP 82102456 A EP82102456 A EP 82102456A EP 0089398 B1 EP0089398 B1 EP 0089398B1
Authority
EP
European Patent Office
Prior art keywords
ceiling
heating furnace
beams
construction
duct
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82102456A
Other languages
German (de)
French (fr)
Other versions
EP0089398A1 (en
Inventor
Tetsuya Tokitsu
Saburo Harada
Jiro Yamasaki
Akihiro Nakama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chugai Ro Co Ltd
Nippon Steel Corp
Original Assignee
Chugai Ro Co Ltd
Nippon Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chugai Ro Co Ltd, Nippon Steel Corp filed Critical Chugai Ro Co Ltd
Priority to AT82102456T priority Critical patent/ATE24044T1/en
Priority to EP82102456A priority patent/EP0089398B1/en
Priority to DE8282102456T priority patent/DE3274576D1/en
Publication of EP0089398A1 publication Critical patent/EP0089398A1/en
Application granted granted Critical
Publication of EP0089398B1 publication Critical patent/EP0089398B1/en
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M5/00—Casings; Linings; Walls
    • F23M5/06—Crowns or roofs for combustion chambers
    • 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
    • C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/32—Casings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/02—Crowns; Roofs
    • F27D1/025—Roofs supported around their periphery, e.g. arched roofs

Definitions

  • the present invention relates to a ceiling construction for a heating furnace which comprises a ceiling portion of the heating furnace, and a plurality of ceiling beams for supporting said ceiling portion, at least one of said beams having a closed cross section for utilisation of its interior as a gas duct.
  • a construction is known from GB-A-3 542 14.
  • the invention also relates to a furnace having such a ceiling construction.
  • the invention is applicable to a heating furnace for heat treating workpieces such as steel slabs, etc.
  • refractory materials for a ceiling of the furnace are generally suspended from ceiling beams constituted by H-shaped steel girders, and provided above the furnace through suspension pipes, hanger tiles, etc. so as to support the weight of such ceiling refractory materials, while combustion air ducts, gas and fuel supply ducts, and exhaust ducts, etc. are normally piped or laid through reinforcing fittings and support fittings fixed to the ceiling beams.
  • GB-A-3 542 14 proposes use of hollow beams as gas ducts and the refractory tiles are suspended therefrom with steel bearers. With this construction, the main steel bearers are thus in direct thermal contact with the refractory material of the ceiling.
  • an object of the present invention is to provide an improved ceiling construction for a heating furnace.
  • Another object of the present invention is to provide an improved ceiling beam construction which is simple in structure and highly reliable in performance, and can be readily incorporated into heating furnaces of various types at low cost.
  • the ceiling construction defined in the first paragraph of this specification is characterized by:
  • the ceiling construction generally includes a plurality of pairs of ceiling beam support posts S (Fig. 2) which are provided adjacent to respective outer faces of opposite side walls W of the heating furnace 1 fixed to studs R at predetermined intervals in the longitudinal direction of said side walls W; ceiling beams 6 connected between each pair of said ceiling beam support posts S; a number of auxiliary ceiling beams B provided between said ceiling beams 6 so as to extend in the longitudinal direction of said heating furnace 1; a plurality of ceiling suspension members 4 such as suspension pipes or the like suitably fixed to the auxiliary ceiling beams B so as to extend in the widthwise direction of the heating furnace 1; and hanger tiles 3 (Fig. 1) integrally provided with a ceiling refractory material 2 of the heating furnace 1 and suspended from said suspension members 4, for example, by metal hangers 5.
  • the ceiling beams 6 at least in the vicinity of burners 10 arranged in the widthwise direction of the furnace 1 are each formed into a closed cross section of approximately a square configuration for simultaneously utilizing the interior of the ceiling beams 6 as combustion air supply ducts 7.
  • the combustion air supply duct 7 thus provided in the ceiling beam 6 is connected, at a suitable position, for example, at one side of the beam 6, with a combustion air supply main duct 8 which is further coupled to an air supply unit A, while the ceiling beam 6 is further formed with a plurality of through-holes O in position, for example, at its other side, to which a branched pipe 9 having a plurality of air supply ducts 9a each connected to the burners 10 is coupled for communication with the air supply duct 7 formed in the ceiling beam 6.
  • a fuel supply unit F for supplying fuel to a nozzle 10a of the burner 10.
  • a suitable heat insulation material 11 may be lined along the internal walls of the combustion air supply ducts 7, and that the closed cross sectional shape of the ceiling beam 6 is not limited to the square shape, but may be modified into various other configurations.
  • the ceiling construction of the present invention may further include a hollow beam forming an exhaust duct or flue arrangement as shown in Figs. 2 and 3 for uniform heating of workpieces with a reduced heating time.
  • the workpieces to be treated are heated by burners provided at upper and lower portions of the furnace, while exhaust gases produced thereby are discharged into a flue or exhaust duct through one exhaust gas discharge opening provided in the ceiling portion at the workpiece charging side of the heating furnace. Therefore, the flow of combustion exhaust gases within the heating furnace is increased in amount at the upper surface side of the workpieces to be treated, thus resulting in a temperature difference more than necessary between the upper surfaces and lower surfaces of the workpieces, with a consequent increase in the heating time as well as various inconveniences at subsequent processes such as a rolling process, etc.
  • the exhaust duct arrangement may, for example, include a plurality of discharge openings (not particularly shown) for exhaust gases which openings are provided at predetermined intervals in upper and lower portions of the workpiece charging side (i.e. left side in Figs. 2 and 3) in the widthwise direction of the heating furnace, and are connected to an upper exhaust duct or flue E disposed between ceiling beams 6b at the left side in Figs.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Tunnel Furnaces (AREA)
  • Supports For Pipes And Cables (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)

Abstract

An improved ceiling beam construction for a heating furnace 1 in which ceiling beams 6 having a closed cross section are adopted for utilizing the interior of the beams simultaneously as ducts 7 for passing gases through them so as to reduce space required for installing separate gas ducts, with a consequent decrease in the number of duct supporting fittings or fixtures.

Description

  • The present invention relates to a ceiling construction for a heating furnace which comprises a ceiling portion of the heating furnace, and a plurality of ceiling beams for supporting said ceiling portion, at least one of said beams having a closed cross section for utilisation of its interior as a gas duct. Such a construction is known from GB-A-3 542 14. The invention also relates to a furnace having such a ceiling construction.
  • The invention is applicable to a heating furnace for heat treating workpieces such as steel slabs, etc.
  • Conventionally, in the heating furnace of the above described type, refractory materials for a ceiling of the furnace are generally suspended from ceiling beams constituted by H-shaped steel girders, and provided above the furnace through suspension pipes, hanger tiles, etc. so as to support the weight of such ceiling refractory materials, while combustion air ducts, gas and fuel supply ducts, and exhaust ducts, etc. are normally piped or laid through reinforcing fittings and support fittings fixed to the ceiling beams. GB-A-3 542 14 proposes use of hollow beams as gas ducts and the refractory tiles are suspended therefrom with steel bearers. With this construction, the main steel bearers are thus in direct thermal contact with the refractory material of the ceiling.
  • Accordingly, an object of the present invention is to provide an improved ceiling construction for a heating furnace.
  • Another object of the present invention is to provide an improved ceiling beam construction which is simple in structure and highly reliable in performance, and can be readily incorporated into heating furnaces of various types at low cost.
  • According to the invention, the ceiling construction defined in the first paragraph of this specification is characterized by:
    • a plurality of pairs of ceiling beam support posts provided adjacent respective outer faces of opposite side walls of the heating furnace at predetermined intervals in the longitudinal direction of said side walls, each pair of said ceiling beam support posts, supporting a respective ceiling beam; a number of auxiliary ceiling beams provided between said ceiling beams so as to extend in the longitudinal direction of said heating furnace; a plurality of ceiling suspension members fixed to the auxiliary ceiling beams so as to extend in the widthwise direction of the heating furnace; and hanger tiles integrally provided with a refractory material of said ceiling portion of the heating furnace and suspended from said suspension members by metal hangers.
  • By the arrangement according to the present invention as described hereinafter, an improved ceiling construction is presented, whose use achieves the object of the invention and removes many disadvantages inherent in conventional ceiling beam constructions of this kind.
  • For a better understanding to the present invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which;
    • Fig. 1 is a fragmentary side sectional view of a heating furnace in which an improved ceiling construction according to the present invention is employed;
    • Fig. 2 is a schematic top plan view, partly in section and illustrating only one half side, of a heating furnace to which the ceiling construction of Fig. 1 may be applied; and
    • Fig. 3 is a side sectional view of the heating furnace of Fig. 2.
  • Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout several views of the accompanying drawings.
  • Referring now to the drawings, there is shown, in Figs. 1 to 3, a ceiling construction for a heating furnace 1 according to one preferred embodiment of the present invention. The ceiling construction generally includes a plurality of pairs of ceiling beam support posts S (Fig. 2) which are provided adjacent to respective outer faces of opposite side walls W of the heating furnace 1 fixed to studs R at predetermined intervals in the longitudinal direction of said side walls W; ceiling beams 6 connected between each pair of said ceiling beam support posts S; a number of auxiliary ceiling beams B provided between said ceiling beams 6 so as to extend in the longitudinal direction of said heating furnace 1; a plurality of ceiling suspension members 4 such as suspension pipes or the like suitably fixed to the auxiliary ceiling beams B so as to extend in the widthwise direction of the heating furnace 1; and hanger tiles 3 (Fig. 1) integrally provided with a ceiling refractory material 2 of the heating furnace 1 and suspended from said suspension members 4, for example, by metal hangers 5.
  • Referring particularly to Fig. 1 showing the construction of the ceiling construction directly related to the present invention, the ceiling beams 6 at least in the vicinity of burners 10 arranged in the widthwise direction of the furnace 1 are each formed into a closed cross section of approximately a square configuration for simultaneously utilizing the interior of the ceiling beams 6 as combustion air supply ducts 7.
  • The combustion air supply duct 7 thus provided in the ceiling beam 6 is connected, at a suitable position, for example, at one side of the beam 6, with a combustion air supply main duct 8 which is further coupled to an air supply unit A, while the ceiling beam 6 is further formed with a plurality of through-holes O in position, for example, at its other side, to which a branched pipe 9 having a plurality of air supply ducts 9a each connected to the burners 10 is coupled for communication with the air supply duct 7 formed in the ceiling beam 6. For supplying fuel to a nozzle 10a of the burner 10, each burner 10 is connected to a fuel supply unit F as shown. It is needless to say that, depending on the kinds of combustion air to be employed, a suitable heat insulation material 11 may be lined along the internal walls of the combustion air supply ducts 7, and that the closed cross sectional shape of the ceiling beam 6 is not limited to the square shape, but may be modified into various other configurations.
  • The ceiling construction of the present invention may further include a hollow beam forming an exhaust duct or flue arrangement as shown in Figs. 2 and 3 for uniform heating of workpieces with a reduced heating time.
  • More specifically, in the conventional heating furnaces, particularly in an upper and lower combustion type walking beam furnace or the like, it is so arranged that the workpieces to be treated are heated by burners provided at upper and lower portions of the furnace, while exhaust gases produced thereby are discharged into a flue or exhaust duct through one exhaust gas discharge opening provided in the ceiling portion at the workpiece charging side of the heating furnace. Therefore, the flow of combustion exhaust gases within the heating furnace is increased in amount at the upper surface side of the workpieces to be treated, thus resulting in a temperature difference more than necessary between the upper surfaces and lower surfaces of the workpieces, with a consequent increase in the heating time as well as various inconveniences at subsequent processes such as a rolling process, etc.
  • In Figs. 2 and 3, the exhaust duct arrangement may, for example, include a plurality of discharge openings (not particularly shown) for exhaust gases which openings are provided at predetermined intervals in upper and lower portions of the workpiece charging side (i.e. left side in Figs. 2 and 3) in the widthwise direction of the heating furnace, and are connected to an upper exhaust duct or flue E disposed between ceiling beams 6b at the left side in Figs. 2 and 3 and also to a lower exhaust duct or flue (not shown) provided at the lower portion of the heating furnace 1, so that the exhaust gases in the heating furnace 1 discharged from the respective discharge openings as described above are divided to flow through the upper and lower portions of the heating furnace 1, and exhaust gas flow distribution in the widthwise direction of the upper and lower portions of the furnace 1 is made uniform, for example, by providing dampers in part or all of said discharge openings according to the locations or dispositions of said openings in the widthwise direction of the furnace 1, while, by providing dampers or a damper either in both or one of the upper exhaust duct E and the lower exhaust duct, the flow ratio of the exhaust gases is adjusted to eliminate the temperature difference in heating in the upper and lower surfaces and longitudinal direction of the workpieces for uniform heating of the workpieces on the whole.
  • As is clear from the foregoing description, since it is arranged that the inner spaces of the ceiling beams themselves are also utilized as gas ducts to be laid at the upper portion of the heating furnace, neither particular spaces for installation of the combustion air supply ducts, exhaust ducts nor various metal fittings such as reinforcing fixtures, etc. for such ducts are required, with a consequent reduction of cost for the heating furnace.
  • Although the present invention has been fully described by way of example with reference to the accompanying drawings, it is to be noted here that the scope of protection is defined by the appendant claims.

Claims (7)

1. A ceiling construction for a heating furnace (1) which comprises a ceiling portion (2) of the heating furnace (1), and a plurality of ceiling beams (6) for supporting said ceiling portion (2), at least one of said beams (6) having a closed section for utilisation of its interior as a gas duct (7), characterized by: a plurality of pairs of ceiling beam support posts (S) provided adjacent respective outer faces of opposite side walls (W) of the heating furnace at predetermined intervals in the longitudinal direction of said side walls (W), each pair of said ceiling beam support posts (S), supporting a respective ceiling beam (6); a number of auxiliary ceiling beams (B) provided between said ceiling beams (6) so as to extend in the longitudinal direction of said heating furnace; a plurality of ceiling suspension members (4) fixed to the auxiliary ceiling beams (B) so as to extend in the widthwise direction of the heating furnace; and hanger tiles (3) integrally provided with a refractory material (2) of said ceiling portion (2) of the heating furnace and suspended from said suspension members (4) by metal hangers (5).
2. A ceiling construction as claimed in claim 1, characterized in that at least one beam (6) providing said duct (7) has a closed cross-section of generally square configuration for utilisation of its interior as a combustion air supply duct.
3. A ceiling construction as claimed in claim 1 or 2, characterized in that said beam (6) of closed cross-section is coupled, at one side, with a combustion air supply main duct (8) leading to an air supply unit (A), and at the other side, to burners (10) of said heating furnace (1) through respective branch ducts (9) communicating with said gas duct (7).
4. A ceiling construction as claimed in any one of claims 1 to 3, characterized in that the interior of said beam means (6) is lined with a heat insulating material (11
5. A ceiling construction as claimed in any one of the preceding claims, characterized by an exhaust duct arrangement (E) which includes a plurality of exhaust gas discharging openings which are provided at predetermined intervals in upper and lower portions of a workpiece charging side in the widthwise direction of the heating furnace (1), and which communicate with corresponding upper and lower exhaust ducts of said heating furnace (1).
6. A ceiling construction as claimed in claim 5, characterized in that said exhaust gas discharge openings are varied in the cross-sectional area thereof according to their dispositions in the widthwise direction of said heating furnace (1).
7. A heating furnace comprising a ceiling construction according to any one of the preceding claims.
EP82102456A 1982-03-24 1982-03-24 Ceiling beam construction for heating furnace Expired EP0089398B1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AT82102456T ATE24044T1 (en) 1982-03-24 1982-03-24 CURVED BEARER FOR A HEAT TREATMENT FURNACE.
EP82102456A EP0089398B1 (en) 1982-03-24 1982-03-24 Ceiling beam construction for heating furnace
DE8282102456T DE3274576D1 (en) 1982-03-24 1982-03-24 Ceiling beam construction for heating furnace

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP82102456A EP0089398B1 (en) 1982-03-24 1982-03-24 Ceiling beam construction for heating furnace

Publications (2)

Publication Number Publication Date
EP0089398A1 EP0089398A1 (en) 1983-09-28
EP0089398B1 true EP0089398B1 (en) 1986-12-03

Family

ID=8188947

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82102456A Expired EP0089398B1 (en) 1982-03-24 1982-03-24 Ceiling beam construction for heating furnace

Country Status (3)

Country Link
EP (1) EP0089398B1 (en)
AT (1) ATE24044T1 (en)
DE (1) DE3274576D1 (en)

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE395967C (en) * 1924-05-24 Fritz Preuss Tiltable Martin oven
GB259998A (en) * 1925-10-17 1927-07-28 Fritz Hillmann Improvements in arches for boiler furnaces
GB354214A (en) * 1930-05-02 1931-08-04 Hermann Roemer Improvements in or relating to cooling devices for furnace walls
DE1000954B (en) * 1953-12-28 1957-01-17 Suedwestfalen Ag Stahlwerke Air-cooled hearth vault with cooling channels arranged across the axis of the vault
FR1187129A (en) * 1957-11-07 1959-09-07 Improvements to systems and arrangements for the construction of suspended or semi-self-supporting arches with heating or recovery flues
DE1109824B (en) * 1959-01-21 1961-06-29 Lucien Chevalier Tubular support for a suspended vault
US3133512A (en) * 1962-08-31 1964-05-19 Levi S Longenecker Furnace nose
GB1032617A (en) * 1963-12-03 1966-06-15 Koho Es Gepipari Miniszterium A furnace and a refractory brick for use in the construction thereof
IT1017121B (en) * 1974-07-12 1977-07-20 Studiceram SELF-SUPPORTING FLAT Vault FOR TUNNEL OVENS IN PARTICULAR FOR THE COOKING OF BRICKS

Also Published As

Publication number Publication date
EP0089398A1 (en) 1983-09-28
DE3274576D1 (en) 1987-01-15
ATE24044T1 (en) 1986-12-15

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