CN113699364A

CN113699364A - White powder removing device in bright annealing furnace

Info

Publication number: CN113699364A
Application number: CN202110508196.5A
Authority: CN
Inventors: 潘钰
Original assignee: Chugai Ro Co Ltd
Current assignee: Chugai Ro Co Ltd
Priority date: 2020-05-22
Filing date: 2021-05-10
Publication date: 2021-11-26
Also published as: TW202208639A; JP2021156562A; JP6976381B2

Abstract

Provided is a white powder removing device in a bright annealing furnace, which can remove white powder by a simple structure. The white powder removing device is provided with a circulating pipeline (3), the circulating pipeline (3) guides the atmosphere in a bright annealing furnace to a cooling area of the bright annealing furnace (1) for cooling, and supplies the atmosphere to the bright annealing furnace, and the white powder removing device is provided with the following components in the circulating pipeline: a collection plate (10) for collecting white powder contained in an atmosphere; and a collector (9) for collecting the white powder collected by the collecting plate. The collecting plate is provided in the circulating duct in an introduction duct portion (4) through which the atmosphere flows in a transverse direction intersecting the vertical direction.

Description

White powder removing device in bright annealing furnace

Technical Field

The present invention relates to a white powder removing device in a bright annealing furnace, which can remove white powder by a simple structure.

Background

When a steel strip or the like is heat-treated in a bright annealing furnace, an off-white powder called a so-called white powder is generated in the furnace and adheres to the surface of the steel strip depending on the type of steel. For this reason, patent documents 1 to 3 are known as techniques for preventing white powder from adhering to a steel strip.

In the "method for controlling a bright annealing furnace" of patent document 1, the dew point of the atmosphere in the furnace is lowered to thereby form boron-donating oxideThe partial pressure of water vapor in the furnace atmosphere of the bright annealing furnace is less than 1 x 10^-5. Alternatively, the dew point of the furnace atmosphere in the bright annealing furnace is lowered by introducing a gas containing hydrocarbon into the furnace or by adding a carbon-containing compound to the furnace atmosphere in the bright annealing furnace.

The "continuous annealing furnace" of patent document 2 includes a heating zone for heating a processing material and a cooling zone for cooling the heated processing material, and performs annealing by continuously conveying the processing material from the heating zone to the cooling zone in an atmosphere gas for bright annealing, wherein a guide duct for guiding the atmosphere gas containing a white powder component from the continuous annealing furnace to a white powder removing unit is provided, and the white powder removing unit is provided with: a cooling roller that cools the atmospheric gas to generate white powder; and a removing member that removes white powder generated on the cooling roller from the cooling roller. Specifically, the white powder generated on the outer peripheral surface of the cooling roller is removed by a removing member composed of a blade that presses the outer peripheral surface of the cooling roller.

A "continuous annealing furnace" of patent document 3 has a prechamber with a water cooling jacket, a heating chamber, and a cooling chamber arranged along an internal conveyance path from a loading port to a discharge port, and performs bright annealing treatment continuously on a metal strip loaded from the loading port by conveying the metal strip through the prechamber having a lower temperature than the heating chamber to the heating chamber and then passing the metal strip through the cooling chamber, by supplying a part of reducing atmosphere gas from a supply side of the cooling chamber into the furnace, thereby generating a gas flow flowing toward a supply side of the heating chamber and a gas flow flowing toward the discharge port side of the cooling chamber in the furnace, and supplying another part of the atmosphere gas from the supply side of the prechamber into the furnace, and a circulation pipe for the atmosphere gas, which draws the atmosphere gas in the furnace from the feeding side of the heating chamber to the outside of the furnace and returns the atmosphere gas to the inside of the furnace again, wherein a white powder removing device for removing white powder in the atmosphere gas is provided in the circulation pipe. Specifically, the circulation pipe is provided with a chamber with a water jacket for removing white powder in the atmosphere gas, a cyclone separator, and a filter.

Documents of the prior art

Patent document 1: japanese patent laid-open publication No. 2005-120448

Patent document 2: japanese patent No. 5188448

Patent document 3: japanese patent No. 5489734

Disclosure of Invention

Problems to be solved by the invention

It is extremely difficult to control the generation of white powder by lowering the dew point of the furnace atmosphere as in patent document 1.

In the structure in which the white powder is removed by the removing member as in patent document 2, there is a problem that the mechanism of the removing member is complicated and the scale becomes large.

In the configuration in which white powder is collected by a filter provided in a circulation pipe as in patent document 3, the filter needs to be replaced periodically, and when clogging occurs, problems occur in that the airflow velocity decreases, the cooling performance declines, or a load is applied to the blower.

The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide a white powder removing device in a bright annealing furnace capable of removing white powder with a simple configuration.

Means for solving the problems

The white powder removing apparatus in a bright annealing furnace according to the present invention is characterized by comprising a circulation duct for introducing and cooling an atmosphere in the bright annealing furnace into a cooling zone of the bright annealing furnace and supplying the atmosphere into the bright annealing furnace, the white powder removing apparatus comprising, in the circulation duct: a trap plate that traps white powder contained in the atmosphere; and a collector for collecting the white powder collected by the collecting plate.

The white powder removing apparatus in the bright annealing furnace according to the present invention is characterized in that the trap plate is provided in the circulation duct at a position where the atmosphere flows in a lateral direction crossing the vertical direction.

The white powder removal device in the bright annealing furnace according to the present invention is characterized in that the collection plate is formed in a plurality of pieces so as to be smaller than a pipe diameter of the circulation pipe, and the plurality of collection plates are arranged in a staggered manner in a flow direction of the atmosphere.

The white powder removing apparatus in the bright annealing furnace according to the present invention is characterized in that the trap plate is provided so as to be inclined with respect to a flow direction of the atmosphere.

The white powder removal apparatus in the bright annealing furnace according to the present invention is characterized in that a cooler for cooling the atmosphere is provided in the circulation duct, and the collecting plate is disposed upstream of the cooler in the flow direction of the atmosphere.

Effects of the invention

The white powder removing device in the bright annealing furnace can remove the white powder by a simple structure.

Drawings

Fig. 1 is a schematic explanatory view showing a preferred embodiment of a white powder removing apparatus in a bright annealing furnace according to the present invention.

Fig. 2 is an enlarged view of a portion a in fig. 1.

Fig. 3 is a view in the direction B in fig. 2.

Fig. 4 is an enlarged view corresponding to fig. 2, illustrating another embodiment of the white powder removal device in the bright annealing furnace of fig. 1.

Fig. 5 is an enlarged view of the white powder removing apparatus in the bright annealing furnace of fig. 1, as viewed from the flow direction of the atmosphere, for explaining still another embodiment.

Fig. 6 is a plan view of the white powder removing apparatus in the bright annealing furnace of fig. 5.

Description of reference numerals:

1 a bright annealing furnace,

2, the steel belt is arranged on the steel belt,

3a circulating pipeline is arranged in the device,

3a of the inlet of the tube, and a part of the inlet of the tube,

3b a supply port of the air conditioner,

4 is introduced into the pipe section and, after the introduction,

4a recovery port, 4a, and a recovery port,

4b into the inner surface of the pipe section,

5 a supply duct portion for supplying the liquid to the liquid supply duct portion,

6 is connected with the pipeline part, and the pipeline part is connected with the pipeline part,

7, a cooler is arranged in the water tank,

an air blower (8) is arranged on the upper portion of the frame,

9 a collector, wherein the water is collected by a collector,

10 a collection plate is arranged on the upper surface of the plate,

the wind shield on the upper side of the 11,

12 on the lower side thereof, a windshield,

13 a recovery duct portion for recovering the liquid from the liquid storage tank,

14a collection plate for collecting the liquid from the liquid,

14a capture the upper part of the plate,

14b capture the lower portion of the plate,

15 a plate for trapping the organic substances,

and (5) an S gap.

Detailed Description

Hereinafter, preferred embodiments of the white powder removing apparatus in the bright annealing furnace according to the present invention will be described in detail with reference to the accompanying drawings. The bright annealing furnace 1 of the present embodiment is a continuous annealing furnace filled with an atmosphere for bright annealing mainly containing hydrogen and nitrogen.

As shown in fig. 1, a bright annealing furnace 1 conveys and cools a steel strip 2 heated in a heating zone in a cooling zone continuous to the heating zone. In the bright annealing furnace (hereinafter, referred to as a furnace) 1 of the present embodiment, a cooling zone is disposed downstream of a heating zone, and a steel strip 2 is conveyed from below to above.

In the cooling zone, the lower side in the drawing is an upstream side in the conveying direction of the steel strip 2 (hereinafter, simply referred to as an upstream side), and the upper side in the drawing is a downstream side in the conveying direction of the steel strip 2 (hereinafter, simply referred to as a downstream side).

In order to cool the steel strip 2 in the cooling zone, a circulation duct 3 is provided, and the circulation duct 3 is introduced so as to introduce the atmosphere in the furnace 1, and after the steel strip 2 is cooled by the cooling nozzle, the cooled atmosphere is supplied into the furnace 1.

The circulation line 3 has: an introduction port 3a which communicates with the inside of the furnace 1 in the cooling region and introduces the atmosphere in the furnace 1; and a supply port 3b which communicates with the furnace 1 on the downstream side of the introduction port 3a and supplies the cooled atmosphere into the furnace 1 in the cooling zone.

The circulation line 3 has, for example: two projecting

pipe portions

4, 5 projecting in a lateral direction crossing a conveying direction in an up-down direction with respect to the steel strip 2 in the furnace 1; and a connecting duct portion 6 that connects the two

extension duct portions

4, 5 in the conveying direction.

That is, the two

extension duct portions

4 and 5 extend in a lateral direction intersecting with the vertical direction of the cooling zone in which the furnace 1 is installed. Thus, the atmosphere flows in the lateral direction within the protruding

duct portions

4, 5. In this case, the two

extension duct portions

4 and 5 may be orthogonal to the furnace 1 or may not be orthogonal to the furnace 1.

The two

extension duct portions

4 and 5 are arranged at an interval from each other in the conveying direction, the upstream extension duct portion 4 is an extension duct portion (hereinafter, referred to as an introduction duct portion) 4 connected to the introduction port 3a, and the downstream extension duct portion 5 is an extension duct portion (hereinafter, referred to as a supply duct portion) 5 connected to the supply port 3 b.

The connection duct portion 6 communicating with both the introduction duct portion 4 and the supply duct portion 5 is provided with: a cooler 7 that cools the introduced atmosphere; and a blower 8 for circulating the atmosphere in the circulation duct 3.

The cooler 7 is provided upstream of the blower 8, and the blower 8 is provided at the end of the connecting duct 6 on the side of the supply duct 5. The blower 8 generates an air flow flowing from the connecting duct portion 6 side toward the supply port 3b side.

As shown in fig. 2, in the introduction duct portion 4, a recovery port 4a for recovering white powder contained in the atmosphere generated and introduced in the furnace 1 is provided in a portion forming the lower surface of the introduction duct portion 4.

A collector 9 is provided in the recovery port 4a, the collector 9 is provided so as to cover the recovery port 4a from the outside of the introduction duct portion 4, and a trap plate 10 is disposed above the collector 9.

The collecting plate 10 is provided in the circulation duct 3 at a portion where the atmosphere flows in a lateral direction crossing the vertical direction. The trap plate 10 is disposed upstream of the cooler 7 of the connecting duct portion 6 in the flow direction of the atmosphere. Specifically, the trap plate 10 is provided inside the introduction duct portion 4 where the supply atmosphere flows in the lateral direction.

As shown in fig. 3, the collecting plate 10 is a plate-like member having an area smaller than the diameter area of the pipe of the introducing pipe portion 4. The plate surface of the trap plate 10 is provided on the lower surface of the intake duct portion 4 so as to be substantially perpendicular to the flow direction of the atmosphere flowing through the intake duct portion 4 and to be substantially vertical.

A gap S for allowing the atmosphere to flow is provided around the edge of the trap plate 10 between the inner surface 4b of the introduction duct portion 4 and the gap S. The atmosphere introduced into the duct portion 4 flows into the connecting duct portion 6 through the gap S.

The collecting plate 10 is provided at the downstream edge of the recovery port 4 a. The white powder contained in the atmosphere flowing through the introduction duct portion 4 is arranged to fall onto the collector 9 when colliding with the surface on the upstream side (the introduction port 3a side) of the trap plate 10. That is, the white powder collected by the collection plate 10 is accumulated on the collector 9 and collected by the collector 9.

As shown in fig. 2, the collector 9 has: two openable and

closable dampers

11, 12 which are disposed at a vertical interval; and a recovery duct portion 13 that is provided between the two

dampers

11 and 12 and connects the two

dampers

11 and 12. Each

damper

11, 12 has a sealed structure so that the airflow introduced into the duct portion 4 does not leak to the outside.

The upper damper 11 can switch between communication and disconnection between the inside of the intake duct portion 4 and the inside of the recovery duct portion 13, and the lower damper 12 can switch between communication and disconnection between the inside and the outside of the recovery duct portion 13.

In the bright annealing furnace 1 of the present embodiment, when the steel strip 2 is transported from the heating zone and passes through the cooling zone, the atmosphere in the furnace 1 is introduced into the circulation duct 3 by the blower 8, the atmosphere is cooled in the cooler 7, and the cooled atmosphere is supplied into the furnace so as to be supplied from the supply duct portion 5 side to the cooling nozzle and to be sprayed on the steel strip 2 by the cooling nozzle.

At this time, in the circulation duct 3, the white powder is removed from the circulating atmosphere in the introduction duct portion 4.

That is, the atmosphere introduced from the introduction port 3a flows through the introduction duct portion 4, and the white powder contained in the atmosphere collides with the upstream surface of the trap plate 10 and falls onto the collector 9 to be accumulated.

At this time, at least the upper windshield 11 of the two

windshields

11, 12 of the collector 9 is closed.

When collecting the white powder accumulated on the collector 9, the upper damper 11 is first opened with the lower damper 12 closed. Thereby, the inside of the introduction duct portion 4 communicates with the inside of the recovery duct portion 13, and the accumulated white powder is accommodated in the recovery duct portion 13.

Next, when the upper damper 11 is closed and the lower damper 12 is opened to communicate the inside of the collection duct portion 13 with the outside, the white powder in the collection duct portion 13 is discharged to the outside.

In this way, when the white powder is collected by the collector 9 provided with the two

dampers

11 and 12, the inside of the introducing duct portion 4 does not directly communicate with the outside, and therefore, the white powder can be collected without causing the atmosphere to leak to the outside.

According to the white powder removing apparatus in the bright annealing furnace of the present embodiment, when the atmosphere introduced from the furnace 1 flows through the circulation duct 3, the white powder is caused to collide with the trap plate 10 and fall, and the white powder is collected by the collector 9 disposed below the trap plate 10.

Therefore, in order to collect the white powder, a large-scale apparatus or mechanism is not required, and the white powder can be sufficiently removed by a simple structure in which only the collecting plate 10 and the collector 9 are provided.

Since it is not necessary to take time and effort to replace the filter when removing the filter as in patent document 3, the maintenance property is also excellent.

Since the collecting plate 10 is provided in the introducing duct portion 4 through which the atmosphere flows in the lateral direction, the white powder can be easily collected by utilizing a phenomenon that the white powder colliding with the collecting plate 10 naturally falls.

Since the collecting plate 10 is disposed upstream of the cooler 7 of the circulation duct 3, the white powder contained in the atmosphere can be removed before being sent to the cooler 7. Therefore, clogging of the cooler 7 by the white powder can be suppressed.

In the present embodiment, an example in which the collecting plate 10 is disposed on the upstream side of the cooler 7 has been described, but the collecting plate 10 may be disposed on the downstream side of the cooler 7.

In fig. 4 to 6, another embodiment of the above-described embodiment is shown. In the above embodiment, the example in which the collecting plate 10 is arranged upright has been described, but the present invention is not limited thereto.

For example, as shown in fig. 4, the collection plate 14 may be inclined with respect to the flow direction of the atmosphere with the upper portion 14a side of the collection plate 14 positioned upstream of the lower portion 14b side.

In this case, the length of the collecting plate 14 can be made longer than in the case of the standing arrangement. The trap plate 14 is lengthened to expand the area, thereby being able to trap more white powder and to suppress the resistance to the air flow to be small.

In the above-described embodiment and the other embodiment, an example in which one

collecting plate

10, 14 is provided is described, but the present invention is not limited thereto.

For example, as shown in fig. 5 and 6, a plurality of collecting plates 15 having an area sufficiently smaller than the pipe diameter area of the circulation pipe 3 may be arranged above the collector 9 in a staggered manner in the flow direction of the atmosphere. In this case, the area of the collecting plate 15 with respect to the pipe diameter can be reduced in the cross section at the predetermined position of the circulation pipe 3. This ensures a wider flow path of the atmosphere, and thus allows the atmosphere to flow smoothly.

In addition, when the circulation duct 3 is observed as a whole, the total area of the plurality of small collecting plates 15 combined is wider than that of the case where one collecting

plate

10 or 14 is provided, and therefore, more white powder can be collected. Therefore, more white powder can be collected while suppressing the resistance to the flow of the atmosphere to be small.

In addition, the above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to limit the present invention. It is to be understood that the present invention may be modified or improved without departing from the gist thereof, and equivalents thereof are also included in the present invention.

Claims

1. A white powder removing device in a bright annealing furnace is characterized in that,

the white powder removing apparatus includes a circulation duct for introducing and cooling an atmosphere in the bright annealing furnace into a cooling zone of the bright annealing furnace and supplying the atmosphere into the bright annealing furnace,

the white powder removing device is provided with the following components in the circulating pipeline: a trap plate that traps white powder contained in the atmosphere; and a collector for collecting the white powder collected by the collecting plate.

2. The apparatus for removing white powder in a bright annealing furnace according to claim 1,

the collecting plate is provided in the circulation duct at a position where the atmosphere flows in a lateral direction crossing the vertical direction.

3. The apparatus for removing white powder in a bright annealing furnace according to claim 1 or 2,

the collecting plates are formed to be smaller than the pipe diameter of the circulation pipe and provided in plural, and the collecting plates are arranged in a staggered manner in the flow direction of the atmosphere.

4. The apparatus for removing white powder in a bright annealing furnace according to any one of claims 1 to 3,

the trap plate is provided so as to be inclined with respect to the flow direction of the atmosphere.

5. The apparatus for removing white powder in a bright annealing furnace according to any one of claims 1 to 4,

the circulation duct is provided with a cooler for cooling the atmosphere, and the collecting plate is disposed upstream of the cooler in the flow direction of the atmosphere.