JPH09143651A - Ash cleaning method and cleaning device for continuos hot dip metal coating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ash cleaning method and cleaning device for continuous hot dip metal coating equipment capable of rapidly and easily cleaning ashes without requiring manual labor. SOLUTION: A blow pipe 25 connected to a pressurized gas supply source having a nozzle 26 at its front end is inserted into an intermediate chamber 10 disposed between the steel strip outlet section of a heat treatment furnace and a downchute forming the descending path of the steel strip 1 into a molten metal vessel. The gas ejected from this nozzle 26 is blown to the ashes deposited or stuck in the intermediate chamber 10. The dusty gas in which the ashes are suspended is sucked outside from a discharge port 22 disposed in the intermediate chamber 10, by which the dust is collected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a facility for performing continuous plating such as zinc / aluminum plating by immersing a steel strip in a molten metal bath after heat treatment.
The present invention relates to a method and an apparatus for removing molten ash in a low temperature portion above a downshout by causing molten metal vapor to rise in the downshout.

[0002]

2. Description of the Related Art Generally, in a continuous type zinc-aluminum plating facility, zinc vapor generated in a molten metal tank rises in a downshout, and a roll chamber in which a turning roll is provided above the downshout is built. Intrudes into the cooling zone of the heat treatment furnace that follows the roll chamber and adheres and accumulates as ash (zinc white) on various parts inside the furnace, and the ash drops or soars and adheres to the running steel strip. And caused a plating failure.

Therefore, in order to remove this ash, conventionally, after a predetermined operating time, the inside of the furnace was gas-pumped to an atmospheric atmosphere, and then the operator manually cleaned the inside of the furnace, which was troublesome. , Again, repurposing the atmosphere gas in the furnace
It was time-consuming and expensive.

[0004]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the prior art, and is a continuous hot-dip galvanizing facility that can easily clean ash in a short time without requiring manual labor. An ash cleaning method and a cleaning device are provided.

[0005]

According to the ash cleaning method of the present invention, however, the ash cleaning method is provided between the steel strip outlet of the heat treatment furnace and the down shoe for forming the descending path of the steel strip into the molten metal tank. A spray pipe having a nozzle at the tip and connected to a pressurized gas supply source is inserted into the intermediate chamber, and the gas ejected from the nozzle is sprayed onto the ash accumulated or adhered in the intermediate chamber, and the ash floats. It is characterized in that the dust-containing gas is sucked outside through an exhaust port provided in the intermediate chamber to collect dust.

Further, the ash cleaning apparatus of the present invention is provided between the steel strip outlet of the heat treatment furnace and a down shoe forming a descending path of the steel strip into the molten metal tank, and provided with a turning roll. An intermediate chamber, a blowing pipe that has a nozzle at the tip portion that penetrates the wall surface of the intermediate chamber and is inserted into the intermediate chamber, and a blowing pipe that is connected to a pressurized gas supply source, and reciprocates the blowing pipe in the longitudinal direction of the pipe. A reciprocating drive device that is driven to change the insertion depth into the heating chamber, an exhaust port provided in the wall surface portion of the intermediate chamber, and a dust-containing gas that is connected to the exhaust port and sucks dust-containing gas in the intermediate chamber. And a dust collecting device that

In the method and apparatus of the present invention, if a gas of the same kind as the atmosphere gas for the heat treatment furnace is used as the pressurized gas, repurging of the atmosphere gas after cleaning is not required, so that time and cost are saved. It is preferable because it can be small.

Further, in the apparatus of the present invention, when the base of the spray tube is rotatably supported around the central axis of the tube and a rotary drive device for rotationally driving the spray tube is provided, accumulation / deposition in various parts of the intermediate chamber occurs. This is preferable because the gas can be surely blown to the attached ash over a wide range. The term "rotation" in the present invention also includes the case where the spray tube is reciprocally swung about the central axis by a predetermined angle (for example, 360 degrees).

Further, in the apparatus of this application, if an atmosphere gas seal device is provided between the steel strip outlet of the heat treatment furnace and the intermediate chamber, this seal device shuts off the heat treatment furnace and the intermediate chamber. During the cleaning, the dust-containing gas enters the heat treatment furnace, and when a gas other than an atmospheric gas such as air is used as a pressurized gas for cleaning, the gas enters the heat treatment furnace, and the heat treatment furnace This is preferable because it is possible to prevent the atmospheric gas from flowing out.

[0010]

In the present invention, the molten metal vapor rising from the molten metal tank portion in the downshout solidifies in the intermediate chamber into ash, and hardly penetrates into the heat treatment chamber. The gas ejected from the nozzle of the spray pipe is blown against the ash that has accumulated and adhered to various parts of this intermediate chamber to raise the ash, and the dust-containing gas in which this ash floats is sucked from the exhaust port and collected. To be done. Therefore, it is not necessary to manually clean the intermediate chamber manually.

Further, in the device of the present invention, since the spray tube is reciprocally driven in the longitudinal direction by the reciprocating drive device, the intermediate chamber can be scavenged over a wide range to surely raise the ash deposited and adhered to each part. it can.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes a steel strip, which is conveyed in a heat treatment furnace 2 to be heat treated (surface cleaning and annealing), and immersed in a molten metal (zinc-aluminum alloy in this embodiment) 4 in a molten metal tank 3. After that, it travels on the upward pass line P and is cooled by a cold air blowing device (not shown), and the plating is completed.

Numeral 10 is an intermediate chamber connected between the steel strip outlet 5 of the heat treatment furnace 2 and the downshoot 7 in which the lower end snout 6 is immersed in the molten metal 4, and an inlet 11 is provided. ,
It comprises a compartment 12 and a roll chamber 13 having a turning roll 14. Reference numeral 8 is a hearth roll, and 15 is an atmosphere seal device provided in the inlet portion 11. The seal door 1 made of a refractory material is attached to the tip of a rod 16 which is directly driven by a drive device (not shown).
7 and 18 are attached, and these seal doors are guided reciprocally in the linear movement direction by guides 19 and 19 fixed to the inlet portion 11.

Reference numeral 21 is a gas spraying device, and 22 is an intermediate chamber 1.
The exhaust port is provided on the ceiling of No. 0, and in this embodiment, it is provided in each of the compartment 12 and the roll chamber 13. Reference numeral 23 is a multi-tube heat exchanger for preheating the atmospheric gas used in the heat treatment furnace 2. The gas spraying device 21 is, as shown in FIG.
The base portion 25b of the spray pipe 25, which is provided with the nozzle 26 at the tip portion 25a inserted into the intermediate chamber 10 and is arranged vertically to the side wall 10a of the intermediate chamber 10, is mounted on the carriage 31 of the reciprocating drive device 30 on the bearings 41, 41. It is rotatably supported by. 2
A hose 7 is connected to a pressurized N ₂ gas supply source (not shown), and is connected to a base end portion 25c of the spray pipe 25 via a rotary joint 28. Reference numeral 29 is a seal device provided on the side wall 10a of the intermediate chamber 10 through which the spray pipe 25 penetrates.

In the reciprocating drive device 30, a rail 33 is laid on a frame 32 installed on a foundation, a carriage 31 is movably mounted on the rail 33, and the frame 32 is mounted on the frame 32. A chain 36 wound around a sprocket 34, 35 that is axially supported.
Further, a bracket 37 fixed to the lower part of the carriage 31 is connected to the frame 32, and a motor 38 for chain-driving the sprocket 34 is attached to the frame 32.

Further, in this embodiment, the spray pipe 25 is rotatably supported by the bearings 41, 41 as described above, and the trolley is provided with the motor 43 for chain-driving the sprocket 42 fixed to the spray pipe 25. A rotary drive device 40 mounted on the device 31 is provided.

Reference numeral 50 is a dust collecting apparatus connected to the exhaust port 22 via an exhaust pipe 51. A dust collecting box 52 having a filter filled therein is connected to a suction port 53a of a suction fan 53. Discharge port 53b of the suction fan 53 is connected to the N ₂ gas storage tank (not shown), N ₂ gas discharged from the discharge port 53b but is recycled is supplied after pressing spray pipe 25 again, other applications May be used for.

Next, a method for cleaning the ash using the above apparatus will be described. During continuous plating, the zinc vapor that evaporates from the liquid surface of the molten metal 4 is cooled down.
Inside the intermediate chamber 10 to be solidified by being cooled and solidified to ash (zinc white) on the inner wall surface 10b of the intermediate chamber 10 and the like.
Adheres or deposits.

Then, after a predetermined operation time has elapsed, the steel strip 1 is extracted to the outside of the intermediate chamber 10 and then the atmosphere seal device 1 is used.
The doors 17 and 18 of No. 5 are driven to move downward to bring them into contact with the bottom of the entrance portion 11 to bring them into a sealing state, and the carriage 31 is driven in the direction of arrow X by the reciprocating drive device 30 and the rotary drive device 4
0 causes the spray pipe 25 to rotate at a low speed in a certain direction, and pressurization N
₂ Gas is supplied into the blowing pipe 25, and the suction fan 53 is operated.

As a result, the spray pipe 25 is rotated and advanced from the retracted position shown by the solid line in FIG. 2, and the N ₂ gas ejected from the nozzle 26 is supplied to the inner wall surface 10b of the intermediate chamber 10 and the pipe group of the heat exchanger 23. The ash that has been sprayed onto each part such as 23a and the bottom surface of the bender part 23b and adhered or accumulated on these parts is blown off and floated in the intermediate chamber 10. The dust-containing gas composed of N ₂ gas in which the ash is suspended is sucked from the exhaust port 22, flows into the dust collecting box 52 via the exhaust pipe 51, and the ash is separated and collected, and then the ash of the suction fan 53. It flows out from the discharge port 53b as dust removal gas.

When the spray tube 25 reaches the forward end position shown by the chain line in FIG. 2, the spray tube 25 is driven in the direction of the arrow Y by the reciprocating drive device 30, and the spray tube 25 is repeatedly reciprocally driven a predetermined number of times. After reciprocating (for example, 5 to 6 times),
The spray pipe 25 is stopped at the first retracted position, the rotational drive is stopped, the supply of N ₂ gas and the operation of the dust collector 50 are stopped, and the cleaning is completed. After that, heat treatment furnace 2
To release the seal by the atmosphere seal device 15,
The steel strip 1 may be passed through and the plating may be restarted.

As described above, the ash can be easily cleaned in a short time without operating the cleaning device and manpower. Further, in this embodiment, the spray pipe 2
As the cleaning gas ejected from No. 5, N ₂ gas of the same kind as the atmosphere gas (N ₂ + H ₂ gas) of the heat treatment furnace 2 was used, there is no need for a gas purge in the intermediate chamber 10 when the plating is restarted. The plating interruption time for cleaning can be further shortened.

Further, in this embodiment, since the atmosphere gas seal device 15 is provided at the inlet portion 11 of the intermediate chamber 10 connected to the steel strip outlet portion 5, the atmosphere gas is prevented from flowing out from the heat treatment furnace 2. And the intermediate chamber 10 during cleaning
The dust-containing gas containing ash inside can be prevented from entering the heat treatment furnace 2.

The present invention is not limited to the above embodiment, and the reciprocating drive device 30, the rotary drive device 40, the dust collecting device 50, and the like may have other specific configurations than those described above. Further, the number and arrangement position and direction of the spray pipes 25, the mounting position of the exhaust port 22 and the like may be other than the above.

Further, as shown in FIG. 3 (A), a plurality of nozzles 26 may be attached to the tip portion 25a of the spray pipe 25 with the nozzles facing each other and the mounting positions in the longitudinal direction of the spray pipe being shifted. A plurality of nozzles 26 may be provided radially as shown in FIG. 7B, and in the latter case, the spray tube 25 may be driven by swinging a small angle around the central axis, or this swinging may be performed. The rotation drive may be omitted altogether. The present invention can also be applied to the case where the heat exchanger 23 is not provided.

[0026]

As described above, according to the present invention,
The gas ejected from the nozzle of the spray pipe raises the ash that has accumulated or adhered to each part of the intermediate chamber, and the dust-containing gas of this ash is sucked from the exhaust port to collect dust, so it can be cleaned directly by hand. Ashes can be easily cleaned in a short time without the need for work. In particular, if the same kind of gas as the atmosphere gas for the heat treatment furnace is used as the pressurized gas for cleaning, repurging of the atmosphere gas after cleaning is unnecessary, and the time and cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of an ash cleaning device showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

3 is a main part perspective view showing another embodiment of the spray pipe in FIG. 2. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Steel strip, 2 ... Heat treatment furnace, 3 ... Molten metal tank, 5 ... Steel strip outlet, 7 ... Down shoot, 10 ... Intermediate chamber, 11 ... Inlet, 12 ... Compartment, 13 ... Roll chamber , 15 ... Atmosphere sealing device, 22 ... Exhaust port, 25 ... Spray tube, 25a ... Tip part,
25b ... Base part, 30 ... Reciprocating drive device, 31 ... Cart, 33
... rail, 36 ... chain, 38 ... motor, 40 ... rotation drive device, 41 ... bearing, 43 ... motor, 50 ... dust collecting device, 51 ... exhaust pipe, 52 ... dust collecting box, 53 ... Suction fan.

Claims (6)

[Claims] 1. A pressurized chamber is provided with a nozzle at its tip end in an intermediate chamber provided between a steel strip outlet of a heat treatment furnace and a downshoot forming a descending path of the steel strip into a molten metal tank. Insert a spray pipe connected to the source, spray the gas ejected from the nozzle to the ash that has accumulated or adhered to the intermediate chamber, and the dust-containing gas in which the ash floats is exhausted from the exhaust port provided in the intermediate chamber to the outside. A method for cleaning ash in a continuous hot-dip galvanizing facility, which is characterized by sucking into and collecting dust. 2. The ash cleaning method in a continuous type hot dip galvanizing facility according to claim 1, wherein a gas of the same kind as the atmosphere gas for the heat treatment furnace is used as the pressurized gas. 3. An intermediate chamber having a turning roll provided between a steel strip outlet of a heat treatment furnace and a downshoot forming a descending path of the steel strip into a molten metal tank, and the intermediate chamber. Of the spray tube connected to a pressurized gas supply source with a nozzle at the tip end inserted into the intermediate chamber through the wall surface of the spray tube, and the spray tube is reciprocally driven in the longitudinal direction of the tube to enter the heating chamber. A reciprocating drive device for changing the insertion depth, an exhaust port provided in a wall surface portion of the intermediate chamber, and a dust collecting device connected to the exhaust port for sucking and collecting dust-containing gas in the intermediate chamber. An ash cleaning device in a continuous hot dip metal plating facility, which is characterized in that 4. The ash cleaning apparatus in a continuous hot dip galvanizing facility according to claim 3, wherein a gas of the same kind as the atmosphere gas for the heat treatment furnace is used as the pressurized gas. 5. The continuous melting system according to claim 3, wherein a base of the spray tube is rotatably supported around a central axis of the spray tube, and a rotary drive device for rotationally driving the spray tube is provided. Ash cleaning device in metal plating equipment. 6. The ash cleaning in a continuous hot-dip galvanizing facility according to claim 3, wherein an atmosphere gas seal device is provided at the inlet of the intermediate chamber connected to the steel strip outlet of the heat treatment furnace. apparatus.