JPH09145259A - Hot air blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain excellent heat resistance and to eliminate the possibility of a nozzle plate being inclined due to thermal de formation. SOLUTION: A pair of upright walls made of refractory such as firebricks are provided in parallel, with a prescribed space between them, on a hearth surface 9 and stepped parts 11 are formed on the opposed faces of the upper parts of the upright walls 8 respectively. Flange parts 13 are formed at the opposite end edges of a chamber 12 formed of a heat-resistant alloy and the chamber 12 is supported in a suspended manner between the two upright walls 8 by setting the flange parts 13 on the stepped parts 11, while a nozzle plate 1 wherein a hot air blast nozzle 18 is formed is laid on the upper end faces of the upright walls 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot air blowing furnace for blowing hot air into a furnace to heat a heat-treated object such as a metal strip.

[0002]

2. Description of the Related Art In a heat treatment furnace in which high temperature hot air is blown against a material to be heated in a furnace to heat treat metal strips or the like, conventionally, a floater for blowing hot air, a chamber for blowing air, etc. are made of heat-resistant steel plates. It maintains heat resistance.

However, even if the heat-resistant steel sheet is repeatedly heated to a high temperature, cleaving may proceed, causing the side wall of the chamber to buckle and deform, which may hinder the blowing of air. In particular, when hot air having a high temperature of 1000 ° C. or more is blown, the deformation is inevitable even if a super heat resistant steel plate such as Inconel 600 is used.

Further, if the chamber is deformed, the nozzle plate, which is conventionally provided integrally with the chamber, may be tilted, so that the hot air may be blown out from the nozzle portion. It was

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention is intended to provide a hot air blowing furnace which is further excellent in heat resistance and which does not cause the nozzle plate to be inclined due to its thermal deformation.

[0006]

To this end, a hot-air blowing furnace according to the present invention comprises a pair of standing walls made of refractory material such as bricks, which are raised parallel to each other at predetermined intervals on a furnace floor surface, and each standing Steps are respectively formed on the opposite surfaces of the upper part of the wall, and flanges are formed on both upper edges of the chamber formed of the heat resistant alloy,
By mounting the flange portion on the stepped portion, the chamber is supported in a suspended manner between the standing walls, and a nozzle plate having hot air blowing nozzles is mounted on the upper end surface of each standing wall. It is characterized by being placed. Further, the present invention is characterized in that, in the hot-air blowing furnace, a flexible heat-resistant sheet is extended from a flange portion onto an upper end surface of a standing wall, and a nozzle plate is placed on the heat-resistant sheet. And

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the drawings with respect to a hot air blowing furnace for continuously heat treating a metal strip. In the illustrated hot air blowing furnace, hot air is blown from a nozzle plate 1 provided on the hearth and the metal strip 2 is blown by the wind pressure.
Is floated and conveyed in the direction of the arrow. FIG. 1 shows a part of the elongated furnace body 3 in a vertical sectional view, and FIG. 2 shows a horizontal sectional view. In the figure, 4 is a fan for circulating the in-furnace gas provided in the ceiling of the in-furnace, 5 is a ceiling duct for guiding the in-reactor gas absorbed by the fan 4, and 6 is inside both side walls of the furnace body 3. It is a vertical duct installed in. Further, 7 is a heating radiant tube arranged in the furnace body 3.

As shown in FIG. 3, reference numeral 8 denotes a pair of upstanding walls in which a refractory material 10 such as a brick is stacked on the hearth surface 9 and is raised in parallel on the hearth surface 9 at a predetermined interval. Step portions 11 are formed on the opposing surfaces of the upper portion of the standing wall 8. Reference numeral 12 denotes a chamber formed by bending a heat-resistant alloy plate having a thickness of several millimeters, such as Inconel 600, into a raised shape, and welding the upper end edges of the heat-resistant alloy plate to laterally long angle-shaped flange portions 13. The chamber 12 by mounting the
Are suspended between the upstanding walls 8 so that a gap 14 is formed between the bottom surface of the chamber 12 and the hearth surface 9. By providing the chamber 12 in this way, the hot air inside does not directly contact the refractory 10 and dust and the like are prevented from scattering from the surface of the refractory 10 into the hot air.

By welding one side of the flange 13 to the upper edge of the flange 13 and extending it on the upper end surface 16 of the standing wall 8, the chamber 12 and the nozzle plate 1 are airtightly connected and can be made thin. It is a flexible heat resistant sheet.

On the other hand, the nozzle plate 1 is, as shown in FIG.
A pair of slit-shaped hot air blowing nozzles 18 are formed on both sides of the horizontal plate portion 17, and the nozzle plate 1 is attached to the standing wall 8.
It is placed on the heat resistant sheet 15 on the upper end surface 16 of the. In addition,
The nozzle plate 1 is also made of a super heat resistant alloy plate.
Therefore, the in-furnace gas absorbed by the fan 4 is sent to the chamber 12 through the ceiling duct 5 and the vertical duct 6,
The metal strip 2 can be floated by being blown from the hot air blowing nozzle 18 of the nozzle plate 1 to heat the metal strip 2 to a required temperature.

As described above, since the nozzle plate 1 is directly supported by the standing wall 8 and is connected to the chamber 12 via the flexible heat-resistant sheet, even if the chamber 12 is thermally deformed, it is deformed. Can be prevented from being transmitted to the nozzle plate 1, and the nozzle plate 1 can always be kept in a horizontal state. Also,
Since the chamber 12 is supported in a suspended manner between the pair of upright walls 8, there is no risk of buckling deformation even if creep is caused by hot air, and the heat resistance is greatly improved.

[0012]

As described above, in the hot air blowing furnace of the present invention, since the nozzle plate and the chamber are supported by the standing wall made of refractory, there is no fear that the nozzle plate is inclined due to the deformation of the chamber. It has a beneficial effect of significantly improving heat resistance.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a part of a hot air blowing furnace according to the present invention.

FIG. 2 is a horizontal sectional view showing a part of a hot air blowing furnace according to the present invention.

FIG. 3 is an enlarged sectional view of a main part of FIG. 1;

FIG. 4 is a perspective view of a nozzle plate.

[Explanation of symbols]

 1 Nozzle Plate 2 Metal Strip 3 Furnace Body 4 Fan 8 Standing Wall 9 Hearth Surface 11 Step 12 Chamber 13 Flange 14 Gap 15 Heat Resistant Sheet 16 Top Surface 17 Water Flat Plate 18 Hot Air Blowing Nozzle

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area F27D 7/00 F27D 7/00 A

Claims (2)

[Claims] 1. A pair of standing walls made of refractory material such as bricks are erected parallel to each other on a hearth surface at a predetermined interval, and stepped portions are formed on opposite surfaces of the upper parts of the standing walls, respectively. Form flanges on both upper edges of the chamber made of heat resistant alloy,
By mounting the flange portion on the stepped portion, the chamber is supported in a suspended manner between the standing walls, and a nozzle plate having hot air blowing nozzles is mounted on the upper end surface of each standing wall. A hot air blowing furnace characterized by being placed. 2. A flexible heat-resistant sheet is extended from a flange portion onto an upper end surface of a standing wall, and a nozzle plate is placed on the heat-resistant sheet. Hot air blowing furnace as described.