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EP-4735816-A1 - BELL-TYPE FURNACE

EP4735816A1EP 4735816 A1EP4735816 A1EP 4735816A1EP-4735816-A1

Abstract

The invention relates to a bell-type furnace (1) comprising a mounting (3) and a process hood (2) which can be arranged on the mounting (3) in order to form a process chamber (6) for at least one object to be processed and which is arranged so as to directly adjoin the process chamber (6). The bell-type furnace also comprises a heating device (13) for controlling the temperature of the at least one object. The invention is characterized in that the process hood (2) has an inner sleeve (9), the outer surface of which is at least partly surrounded by a thermal insulation (10), or the thermal insulation (10) is arranged so as to directly adjoin the process chamber (6).

Inventors

  • EBNER, ROBERT
  • SAUSCHLAGER, ANDREAS

Assignees

  • EBNER Industrieofenbau GmbH

Dates

Publication Date
20260506
Application Date
20240524

Claims (20)

  1. 1. Hood furnace (1) comprising a base (3) and a process hood (2) which can be arranged on the base (3) to form a process chamber (6) for at least one object to be processed and which is arranged directly adjacent to the process chamber (6), and with a heating device (13) for controlling the temperature of the at least one object, characterized in that the process hood (2) has an inner shell (9) which is surrounded at least in sections by thermal insulation (10) on an outer surface or that the thermal insulation (10) is arranged directly adjacent to the process chamber (6).
  2. 2. Hood furnace (1) according to claim 1, characterized in that the process hood (2) forms an outer boundary of the hood furnace (1).
  3. 3. Hood furnace (1) according to claim 1 or 2, characterized in that the process hood (2) has a protective cover (11) on an outer surface of the thermal insulation (10).
  4. 4. Hood furnace (1) according to one of claims 1 to 3, characterized in that the process hood (2) has beads (12).
  5. 5. Hood furnace (1) according to claim 4, characterized in that the beads (12) are designed as undercuts.
  6. 6. Hood furnace (1) according to one of claims 1 to 5, characterized in that the process hood (2) has a jacket section (7) and is designed free of fittings at least in the region of the jacket section (7).
  7. 7. Hood furnace (1) according to one of claims 1 to 6, characterized in that an electric heating device (13) is arranged in the base (3).
  8. 8. Hood furnace (1) according to claim 7, characterized in that a circulation device for the process chamber atmosphere with at least one guide element (23) is arranged in the base (3), and that the electrical heating device (13) is arranged in the region of the at least one guide element (23).
  9. 9. Hood furnace (1) according to one of claims 1 to 8, characterized in that at least one cooling device (25) is arranged in the base (3).
  10. 10. Hood furnace (1) according to one of claims 1 to 9, characterized in that at least one heat exchanger (26) is arranged in the base (3).
  11. 11. Hood furnace (1) according to one of claims 1 to 10, characterized in that a gas guide element (29) which is displaceable in the axial direction (28) is arranged in or on the base (3).
  12. 12. Hood furnace (1) according to one of claims 1 to 11, characterized in that the inner shell (9) is arranged at least in sections at a distance from the thermal insulation (10).
  13. 13. Hood furnace according to claim 12, characterized in that a gas guide cylinder (35) is arranged at least in sections between the inner shell (9) and the thermal insulation (10).
  14. 14. Hood furnace (1) according to claim 13, characterized in that the gas guide cylinder (35) extends over at least 70% of a height (37) of the process chamber (6).
  15. 15. Hood furnace (1) according to claim 13 or 14, characterized in that the gas guide cylinder (35) is arranged at a distance (39) from the inner shell (9) or from the thermal insulation (10) which is selected from a range between 5 mm and 30 mm.
  16. 16. Hood furnace (1) according to one of claims 13 to 15, characterized in that an inflow opening (41) for the gas in the space between the gas guide cylinder (35) and the Inner shell (9) or the thermal insulation (10) formed gas guide channel (36) is formed with a bevel and/or curve (42).
  17. 17. Hood furnace (1) according to one of claims 1 to 16, characterized in that it has at least one temperature measuring element (43) which is arranged at a height which corresponds to between 50% and 100% of the height (37) of the process chamber (6).
  18. 18. Hood furnace (1) according to claim 17, characterized in that the temperature measuring element (43) is arranged in the region of one end (44) of the gas guide cylinder (35).
  19. 19. Base (3) for a hood furnace (1) comprising a circulation device for a process chamber atmosphere of the hood furnace (1), at least one guide element (23), and at least one connection region for a hood of the hood furnace (1), characterized in that the heating device (13) is an electrical heating device (13) and is arranged in the region of the at least one guide element (23).
  20. 20. Base (3) according to claim 12, characterized in that the hood is designed as a process hood (2) with thermal insulation arranged on an outer surface or as a gas-heated heating hood.

Description

HAUBENQFEN The invention relates to a hood furnace comprising a base and a process hood, which can be arranged on the base to form a process chamber for at least one object to be processed and which is arranged directly adjacent to the process chamber, as well as with a heating device for tempering the at least one object. The invention further relates to a base for a hood furnace comprising a circulation device for a process chamber atmosphere of the hood furnace, at least one guide element, and at least one connection region for a hood of the hood furnace. The invention also relates to a thermal processing plant comprising at least two hood furnaces, each with a base. In addition, the invention relates to a method for tempering at least one object in a hood furnace having a process hood and a base defining a process chamber, comprising the steps of: placing the at least one object on the base, arranging the process hood on the base, tempering the at least one object. Hood furnaces are known from the prior art. For example, EP 2 738 502 A1 describes a hood annealing furnace for the thermal treatment of cold-rolled steel strip, comprising a base with a protective hood that can be placed thereon, under which a protective gas heated by a gas burner is circulated by a fan in order to heat the steel strip, which is rolled up in particular into a coil, under the protective hood in a protective gas atmosphere to a temperature of at least 500 °C. In this hood furnace, an electrical heating device fed by the public power grid is provided with a heating output that essentially corresponds to the heating output of the gas burner, with which the protective gas can be heated independently to a temperature above the recrystallization annealing temperature as an alternative to the gas burner when the gas burner is switched off. The gas burners and the electrical heating device are arranged outside and at a distance from the protective hood in/on a so-called heating hood. Generally, hood furnaces are now operated in such a way that the hoods are exchanged between individual process stages. The protective hood is always present. For example, a heating hood, a cooling hood, etc. are changed, each of which is placed over the protective hood at a certain distance. The distance creates a heating chamber into which, for example, burners burn or in which electrical heating elements are arranged. The thermal energy generated is then transferred via the material of the protective hood to the protective gas for heating the objects to be tempered. The object of the present invention is to provide a more environmentally friendly design of a hood furnace or a thermal processing plant equipped therewith as well as a more environmentally friendly method for tempering an object. The object of the invention is achieved in the hood furnace mentioned at the outset in that the process hood has an inner shell which is at least partially surrounded by thermal insulation on an outer surface or in that the thermal insulation is arranged directly adjacent to the process chamber. Furthermore, the object of the invention is achieved with the base mentioned at the outset, in which the electrical heating device is arranged in the region of the at least one guide element. In addition, the object of the invention is achieved with the above-mentioned thermal processing plant, in which the hood furnaces and/or the bases are designed according to the invention. The object of the invention is also achieved with the method mentioned at the beginning, according to which it is provided that the process hood is used as the only hood during the entire tempering process. The advantage here is that the (immediate) arrangement of the thermal insulation on the process hood directly adjacent to the process chamber reduces the heat loss via this process hood. The base supports this, as it allows thermal energy to be introduced directly into the process chamber atmosphere. As a result, the hood furnace itself can be made smaller, as no further hood, such as a heating hood, etc., is required in addition to the innermost hood (in the case of the invention, the process hood, in the prior art, the protective hood). The radiation surface of a hood furnace can therefore be reduced. In addition to this reduction, a reduction in the space required by the hood furnace can also be achieved. By using a single process hood during the In addition, the energy required for the entire process for tempering an object can be reduced by reducing the number of crane movements required to handle hoods, as is necessary with the state of the art mentioned above. This in turn also allows a reduction in operating effort and, as a result, the realization of a fully automatic hood furnace. Unmanned operation from the start to the end of thermal treatment of an object is possible if necessary. By eliminating the need to move the hood during thermal treatment, a corresponding time saving can al