JPH05195085A - Gas seal device for vertical furnace - Google Patents

Abstract

PURPOSE:To provide a gas seal device for a vertical furnace such as an alloying furnace where the structure of the gas seal device is simple, and the costs for the facilities and the operation are low. CONSTITUTION:A gas seal device 6 consists of a gas seal box 10 which is connected to the outlet end of a soaking zone 5 of a vertical furnace, a sealing gas supplying fan 13 whose discharge port is connected to the gas seal box 10 by means of a duct 11 and whose suction port is connected to the vicinity of the upper outlet of the soaking zone 5 by means of a duct 12, and a guide 14 provided to the section of the inverted-V shape opposite to the upper outlet of the gas seal box 10. The clearance between the inner edge of the guide 14 and a strip 8 is formed as small as practicable. The air of high temperature of 400 to 500 deg.C which rises within the soaking zone 5 is sucked by the fan 13 through the duct 12 in the vicinity of the upper end of the soaking zone, and continuously supplied from the discharge side of the fan 13 to the gas seal box 10 through the duct 11 as the sealing gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas sealing device for a vertical furnace such as an alloying furnace.

[0002]

2. Description of the Related Art In a vertical furnace such as an alloying furnace, conventionally, as shown in FIG. 4, high temperature exhaust gas at 400 ° to 500 ° C. in the soaking zone 05 blows through the upper end outlet into the cooling zone 07 that follows. In order to prevent the circulation, the exhaust duct 08 and the exhaust fan 09 exhaust near the upper end of the soaking zone 05, and at the same time, a seal box 010 and a seal gas supply fan 011 are provided at the upper end of the soaking zone 05 to seal ambient temperature outside air to the seal box 010 The exhaust gas is continuously supplied into the interior of the soaking zone 05 to block the high-temperature exhaust gas from the outlet, and the surplus seal gas is discharged to the upper side. An exhaust fan 012 is provided in the cooling zone 07.

[0003]

By the way, in the conventional device as described above, the exhaust duct 08 of the soaking zone 05 has a long guiding length and occupies a large space. Since the fans 09 and 011 are used in parallel, the cost is high both in terms of equipment and operation.

The present invention solves the above problems of the conventional device,
It is an object of the present invention to provide a new gas sealing device that simplifies the configuration and reduces equipment and operating costs.

[0005]

As a structure for achieving the above object, a gas sealing device for a vertical furnace according to the present invention has a gas sealing box and a sealing gas supply fan connected to a soaking zone outlet end of the vertical furnace. In addition, the exhaust duct of the soaking air is connected to the suction port of the sealing gas supply fan from near the outlet of the soaking band, and the surplus gas is exhausted to the outside on the exhaust side of the gas seal box. Moreover, a guide is provided to allow a part of the exhaust gas to join the surrounding atmosphere and to flow into the inlet of the cooling zone.

[0006]

In the vertical furnace gas seal device of the present invention, the hot air in the soaking zone of the vertical furnace is sucked from the soaking zone by the sealing gas supply fan connected near the upper end of the soaking zone. From the discharge side of the fan, it is sent as a sealing gas through a duct into a seal box connected to the end of the soaking zone.

The sealing gas blocks the upward blowing of the high-temperature exhaust gas from the soaking zone, and the gas passes through the outlet on the upper exhaust side of the seal box and is arranged between the soaking zone and the cooling zone. Most of the excess gas is discharged to the outside along the guide.

At this time, a part of the exhaust gas that rises near the center passes through the inner gap of the guide, and is mixed with the outside air from the side open area in the space on the upper surface side of the guide to become a gas whose temperature has been lowered due to thermal dilution. It enters into the lower entrance of the cooling zone.

As a result, according to the present invention, the number of fans required for discharging soaking air and supplying sealing air can be halved, and the amount of exhaust ducts installed can be greatly reduced.

[0010]

EXAMPLES The present invention will be described below with reference to examples shown in the drawings. FIG. 1 schematically shows a galvanized steel sheet production line equipped with a gas sealing device 6 according to the present invention, 1 is an annealing furnace, and 2 is
Is a plating bath, 3 is an alloying furnace, 4 is a heating zone, 5 is a soaking zone, 6 is a gas sealing device according to the present invention, 7 is a cooling zone,
Reference numeral 8 is a steel plate strip that passes through these devices, and 9 is a molten zinc basis weight adjustment nozzle arranged above the plating bath 2.

The strip 8 heat-treated in the annealing furnace 1 is immersed in the molten zinc in the plating bath 2 and the basis weight is adjusted by the gas sprayed from the nozzle 9, and then the heating zone 4, the soaking zone 5, the gas seal portion 6, It is alloyed through the cooling zone 7 and sent to the next step.

FIG. 2 is a first embodiment of the gas seal device of the present invention, which is shown by enlarging the portion II in FIG. The gas seal device 6 has a gas seal box 10 connected to and attached to the outlet end of the soaking zone 5 of the vertical furnace, a discharge port connected to the gas seal box 10 by a duct 11 and a suction port connected by a duct 12. It is composed of a sealing gas supply fan 13 connected near the upper outlet of the tropical zone 5 and a guide 14 facing the upper outlet of the gas seal box 10 and having an inverted eight-shaped cross section.

The gap between the inner edge of the guide 14 and the strip 8 is preferably as small as possible. In the figure, 15 and 16 are an exhaust duct and an exhaust fan provided in the cooling zone 7.

Next, the operation of the apparatus of this embodiment will be described. The high temperature air of 400 ° C. to 500 ° C. rising in the soaking zone 5 is sucked by the fan 13 through the duct 12 near the upper end of the soaking zone, and the fan is blown. It is continuously supplied as a sealing gas into the seal box 10 through the duct 11 from the discharge side of 13.

The sealing gas that has entered the seal box 10 flows vertically along the flow path in the seal box 10, and the downward flow flows backward from the outlet of the soaking zone 5 to the soaking zone 5. Stop the hot air inside from blowing up.

Most of the surplus gas discharged from the upper outlet of the seal box 10 is discharged to the outside of the cooling zone 7 along the lower surface of the guide 14, and a part of the gas flowing along the surface of the strip 8 is separated from the inner space of the guide 14. After passing through the space of the guide 14, it mixes with the surrounding atmosphere in the space on the upper surface side of the guide 14 to become a gas having a lowered temperature and enters the cooling zone 7 through the lower opening of the cooling zone 7.

FIG. 3 shows a gas sealing device according to a second embodiment of the present invention. In the case of this embodiment, a short duct-shaped guide 1 is used instead of the guide 14 described in FIG.
4'is provided.

As described above, the guide may be freely changed in shape, and the guide is not limited to the above embodiment.

According to the configuration of each of the above-described embodiments, the exhaust gas from the soaking zone 5 is used as the supply gas for sealing,
One fan can be used for both exhaust and supply of sealing gas.

Also, after using as a sealing gas, hot air is naturally exhausted to produce a long duct,
No need to install.

Further, the gas sealing device having the above-mentioned structure can be applied not only to the alloying furnace of the galvanized steel sheet production line illustrated, but also to other equivalent vertical furnaces in general.

Furthermore, the individual configurations of the gas seal box and the guide can be implemented in various modified shapes.

[0023]

As described above, according to the gas sealing device for the vertical furnace of the present invention, the gas sealing box and the sealing gas supply fan are connected to the end of the soaking zone of the vertical furnace, and An exhaust duct for soaking air is provided by connecting from the vicinity of the outlet of the soaking zone to the intake port of the sealing gas supply fan, and the surplus sealing gas is exhausted to the outside on the exhaust side of the gas seal box. By installing a guide that merges the above exhaust gas with the surrounding atmosphere and flows into the cooling zone inlet, the number of fans required for exhausting the soaking air and supplying sealing air is halved, and the amount of exhaust duct installed is significantly reduced. The effect of significantly reducing the cost related to equipment and operation is achieved by simplifying the structure.

[Brief description of drawings]

FIG. 1 is a schematic view of a galvanized steel sheet production line including a vertical furnace equipped with a gas sealing device according to the present invention.

FIG. 2 is an explanatory view of a gas sealing device according to a first embodiment of the present invention in which a portion II in FIG.

FIG. 3 is an explanatory diagram of a gas seal device according to a second embodiment of the present invention.

FIG. 4 is a side view showing a conventional gas seal device.

[Explanation of symbols]

 1 Annealing Furnace 2 Galvanizing Bath 3 Alloying Furnace 4 Heating Zone 5 Soaking Zone 6 Gas Sealing Device 7 Cooling Zone 8 Strip 10 Gas Seal Box 11 Sealing Gas Supply Duct 12 Equalizing Air Exhaust Duct 13 Sealing Gas Supply Fan 14 Guide 14 'Duct-shaped guide 15 Duct 16 Exhaust fan

Claims (1)

[Claims] 1. A gas seal box and a seal gas supply fan are connected and provided at the soaking zone outlet end of a vertical furnace, and
An exhaust duct for soaking air is provided by connecting from a portion near the outlet of the soaking zone to the suction port of the sealing gas supply fan, and excess gas is exhausted to the outside on the exhaust side of the gas seal box, and partly 2. A gas seal device for a vertical furnace, characterized in that a guide is provided for merging the exhaust gas with the surrounding atmosphere to flow into the inlet of the cooling zone.