JP5415096B2 - Plating pot drying heating equipment and drying heating method - Google Patents

Description

The present invention relates to a drying heating equipment for a plating pot for drying an amorphous refractory of a plating pot used in a continuous molten metal plating equipment for a steel strip, and a drying heating method thereof.

Conventionally, drying of amorphous refractories in plating pots used in steel strip continuous molten metal plating equipment forms a flame with metal ingots piled in the pots of plating pots, and forms irregular refractories. It is done by heating. The temperature control in the pot is performed by adjusting the amount of fuel gas (direct heating power) for forming a flame.
However, in the heating by the conventional burner, since the flame is formed in the pot, the temperature is high near the flame (for example, about 1500 ° C.), and the temperature is low in other portions. For this reason, the variation in temperature in the pot becomes large, and as a result, the variation in the temperature of the amorphous refractory also increases, which may cause cracks in the amorphous refractory.

In order to solve the above problem, the following method is disclosed as a method for uniformly drying an irregular refractory with a burner.
For example, Patent Document 1 discloses an amorphous refractory that is provided with a stirring blade and a plurality of burners on the lid of a container in which hot metal or molten steel is placed, and the combustion gas from each burner is stirred by the stirring blade, and is lined in the container. A method for uniformly drying the is disclosed.
Further, Patent Documents 2 and 3 disclose a method for uniformly drying an amorphous refractory lined on a kneading car furnace body using a hot air generator provided outside the kneading car. In addition, the temperature management in the chaotic car furnace body is performed by the thermocouple in the hot air blower tube.

JP-A-6-277822 JP-A-8-27510 JP 2000-161862 A

However, the plating pot is different from the container disclosed in the cited document 1 and the kneading vehicle disclosed in the cited documents 2 and 3, the pot is provided with an induction heating device in communication, and the induction heating device is It has a complicated structure in which a runner (also referred to as an inductor channel) for heating by passing molten metal is formed of an irregular refractory. For this reason, even if the amorphous refractory inside the pot can be heated uniformly, heating of the irregular refractory in the induction heating device may be insufficient, causing the above-described trouble.
Further, the runner of the induction heating apparatus needs to be locally higher than the temperature in the pot in order to sufficiently dry, but it is difficult with a conventional burner.
Furthermore, the metal ingot is piled up in the pot, and the melting of the metal ingot is started after the drying of the amorphous refractory is completed. However, if the temperature in the pot varies, the metal partially melts when the amorphous refractory is dried, and the stacked metal ingot may collapse, damaging the pot.

The present invention has been made in view of such circumstances, and drying and heating a plating pot for heating an amorphous refractory uniformly at a target temperature and drying it, and subsequently enabling it to be used in a continuous molten metal plating facility. An object is to provide a facility and a method for drying and heating the facility.

The drying heating equipment for a plating pot according to the first aspect of the present invention is an induction heating apparatus provided in communication with the inside of the pot and the pot in a state where metal ingots are stacked inside the pot. It is a drying heating equipment for a plating pot that dries the amorphous refractories respectively disposed inside and can be used in a continuous molten metal plating equipment,
A drying heating apparatus is provided that guides hot air obtained by diluting combustion gas generated by a burner with dilution air into the pot through a duct.

In the drying heating equipment for a plating pot according to the first invention, the drying heating device surrounds the cylindrical object with a combustion gas generating means having a cylindrical object on the front side of the burner with a gap. An outer cylinder, an air inlet is provided on the base side of the outer cylinder via a valve, and has dilution air introducing means for introducing the dilution air, and the dilution air is provided on the front side of the outer cylinder. It is preferable to provide a mixing portion with the combustion gas.

In the drying heating equipment for a plating pot according to the first invention, the temperature control of the hot air is preferably performed by changing a mixing ratio of the dilution air to the combustion gas.
In the drying heating equipment for a plating pot according to the first invention, the temperature control of the hot air may be performed by adjusting the amount of combustion heat of the combustion gas.
In the drying heating equipment for a plating pot according to the first aspect of the invention, it is preferable that a curved duct is rotatably provided at a portion inserted into the pot on the front side of the duct.

The plating pot drying and heating method according to the second aspect of the present invention uses the plating pot drying and heating equipment according to the first aspect of the invention, moves the duct, and changes the direction of hot air jetting. , Locally heating the amorphous refractory of the induction heating device and / or heating the amorphous refractory of the pot as a whole.

In the method for drying and heating the plating pot according to the second invention, until the melting of the metal ingot is started, the temperature of the hot air is controlled to be less than the melting point of the metal, and after the melting of the metal ingot is started, It is preferable to control the temperature of the hot air within the range of the melting point of the metal (melting point + 200 ° C.).

In the drying heating equipment for plating pot and the drying heating method according to the present invention, the hot air obtained by diluting the combustion gas generated by the burner with dilution air is used for drying the amorphous refractory. The temperature can be easily maintained, the temperature variation can be minimized, and the trouble of the irregular refractory material caused by the temperature variation can be prevented. In addition, by heating the amorphous refractory of the induction heating apparatus that needs to be dried with hot air, this portion can be reliably dried.
This makes it possible to remove the moisture contained in the amorphous refractory uniformly and sufficiently, and eliminates the possibility that the stacked metal ingot will melt and collapse at an early stage due to partial heating. Can also prevent damage. Therefore, the pot can be continuously used in the continuous molten metal plating facility without performing repair work on the pot.

In addition, when the temperature control of the hot air is performed by changing the mixing ratio of the diluted air to the combustion gas, the temperature control of the hot air can be performed by a simple method.
And when temperature control of hot air is performed by adjusting the amount of combustion heat of combustion gas, temperature control of hot air can be performed by a simple method.
When a curved duct is rotatably provided at a portion inserted into the pot on the front side of the duct, hot air can be blown to a target place with a simple configuration.
Furthermore, when the temperature of the hot air is changed before and after the start of melting of the metal ingot, the amorphous refractory can be reliably dried, and the collapse of the stacked metal ingot can be prevented in advance. Damage can also be prevented.

It is explanatory drawing of the drying heating method of the pot for plating which concerns on one embodiment of this invention. It is explanatory drawing of the drying heating equipment of the pot for plating used for the drying heating method of the pot for plating. It is a partial plane sectional view of the pot and induction heating device which apply the drying heating method of the pot for plating. It is explanatory drawing which shows the temperature pattern of the drying heating method of the pot for the plating.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1 to 3, the drying heating equipment 10 for a plating pot according to an embodiment of the present invention is a pot in a state in which an ingot 12 of zinc (an example of metal) is stacked inside a pot 11. 11 and the two induction heating devices 13 provided in communication with the pot 11 are dried, the ingot refractories 14 and 15 are subsequently melted, the ingot 12 is subsequently melted, and the pot 11 is not shown. It is for making it usable in the continuous hot dip galvanizing equipment (an example of the continuous hot dip metal plating equipment). This will be described in detail below.

The plating pot drying and heating equipment 10 has a drying and heating device 15 a, and this drying and heating device 15 a has combustion gas generating means 16 and dilution air introducing means 17.
The combustion gas generating means 16 includes a cylindrical object 18 that is horizontally disposed on the front side of the burner 20 that forms the flame 19. The burner 20 is provided with a gas supply port 21 for supplying fuel gas and an air supply port 22 for supplying air.
The diluted air introducing means 17 has a base attached to the base of the combustion gas generating means 16, and an inner cylinder 24 that surrounds the cylindrical object 18 with a gap 23 between its inner peripheral surface and the outer peripheral surface of the cylindrical object 18. It has. The outer cylinder 24 is gradually reduced in diameter toward the front side and is tapered, and an air inlet 26 is provided on the base side wall via a butterfly valve (an example of a valve) 25. Yes.

On the front side of the outer cylinder 24, the combustion gas generated by forming a flame 19 in the cylindrical object 18 of the combustion gas generating means 16 and a gap 23 between the cylindrical object 18 and the outer cylinder 24 pass. A mixing unit 27 is provided for mixing the diluted air supplied. A part of the dilution air is also supplied into the cylindrical object 18 from the base side of the cylindrical object 18. The diluted air can be adjusted in inflow by adjusting the opening of the butterfly valve 25.
Thereby, for example, a high-temperature combustion gas of about 1500 ° C. is generated in the cylindrical body 18 of the combustion gas generating means 16, and this combustion gas is diluted with dilution air in the mixing unit 27 to lower the temperature. Can do.
A plurality (four in this case) of legs 28 are attached to the outer cylinder 24.

A duct 29 for guiding hot air generated by diluting the combustion gas with dilution air into the pot 11 is provided at the tip of the outer cylinder 24.
The duct 29 is made of stainless steel that does not melt even when hot air passes through it. As shown in FIG. 1, the curved duct 30 can be rotated at a portion inserted into the pot 11 on the front side of the duct 29. Is provided. Note that the axis of the curved duct 30 is curved so as to have an angle θ (for example, in the range of 20 to 70 degrees, preferably 30 to 60 degrees) with respect to the vertical direction.
The duct 29 is wound with a heat insulating material (not shown) for heat insulation, but is not wound around the curved duct 30.
Further, the duct is not limited to the above-described configuration, and may be, for example, a bellows shape as long as it can withstand the temperature of hot air and can change the direction of hot air ejection.

Accordingly, by rotating the curved duct 30 with respect to the duct 29, the hot air blowing direction can be changed and used to dry the amorphous refractories 14 and 15.
The temperature of the hot air is measured by thermocouples arranged at a plurality of locations in the conveyance direction in the duct 29 and the curved duct 30, and is controlled within a range of, for example, 100 ° C. or more and 700 ° C. or less based on this temperature (feedback) control).
This temperature control method can be easily performed by adjusting the opening of the butterfly valve 25 and changing the mixing ratio of air to the combustion gas, but by adjusting the amount of combustion heat of the combustion gas. Also good. As a method for adjusting the amount of combustion heat, for example, there is a method for adjusting the amount of fuel gas sent to the burner 20.

As shown in FIGS. 1 and 3, the drying heating equipment 10 for the plating pot shown above has an irregular refractory 14 arranged inside the pot 11 and an irregular heater arranged inside the induction heating device 13. Used to dry the regular refractory 15.
In addition, the irregular-shaped refractory 14 of the pot 11 is arrange | positioned in the part where a shape becomes complicated like the inner corner | angular part of the pot 11, or the attachment part of the induction heating apparatus 13, and another part is a regular refractory. Brick 31 is arranged.
Further, the amorphous refractory 15 of the induction heating device 13 is disposed so as to cover the coil 32 of the induction heating device 13, and forms a runner 33 communicating with the inside of the pot 11. Thereby, the molten zinc in the pot 11 can be heated by the induction heating device 13 while passing through the runner 33.

Then, the drying method of the pot for plating which concerns on one embodiment of this invention is demonstrated.
First, amorphous refractories 14 and 15 are arranged inside the pot 11 and inside the induction heating device 13, respectively. As described above, the brick 31 is also arranged inside the pot 11.
After the ingot 12 is stacked in a plurality of stages through the zinc plate 34 inside the pot 11, a plurality of lids 35 to 37 made of a refractory material are provided above the pot 11. In this embodiment, the case where zinc is used as the metal to be melted is described. However, not only zinc but also a zinc alloy such as a conventionally known zinc aluminum alloy used for plating may be used.
And the curved duct 30 is each inserted in the pot 11 from the opening parts 38-40 formed in each lid | cover 35-37, and the amorphous refractories 14 and 15 are prepared for drying. The outer cylinder 24 of the drying and heating device 15a is attached and fixed via a plurality of legs 28 on a work table 41 disposed above the lids 35 to 37.

When supplying hot air into the pot 11, first, fuel gas and air are supplied to the burner 20, and the fuel gas is burned to generate a high-temperature combustion gas of about 1500 ° C. in the cylindrical body 18.
At this time, by adjusting the opening degree of the butterfly valve 25, the amount of diluted air flowing into the outer cylinder 24 at a normal temperature (for example, more than 0 ° C. and 40 ° C. or less) is controlled. The temperature is controlled by dilution, hot air having a temperature of about 100 to 700 ° C. is created, introduced into the pot 11 through the duct 29 and the curved duct 30, and the amorphous refractories 14 and 15 are dried. Note that, as described above, the temperature control is performed based on the temperature of the hot air flowing in the duct 29 and the curved duct 30 so that the temperature is set in advance and the mixing ratio of the diluted air to the combustion gas and the combustion heat amount of the combustion gas. It is done by adjusting. The hot air supplied into the pot 11 is exhausted out of the pot 11 through the exhaust ports 42 and 43 of the lid 36.

Here, an example of the temperature pattern of the hot air in the drying process of the amorphous refractory will be described.
The temperature of the hot air is preferably controlled to be lower than the melting point of zinc (for example, 420 ° C. or lower) until the zinc ingot 12 starts to melt. For example, as shown in FIG. 4, it is possible to keep the inside of the pot 11 at a relatively low temperature of about 120 to 200 ° C. and to sufficiently dry the moisture contained in the amorphous refractory 14. It is important to prevent 15 troubles.
In addition, after starting the melting of the zinc ingot 12, which is the final stage of drying (that is, the stage where at least the surface layers of the amorphous refractories 14 and 15 are dried), the temperature of the hot air is changed from the melting point of zinc (melting point + 200 ° C.). For example, it is good to control within the range of melting | fusing point or more and 600 degrees C or less. For example, as shown in FIG. 4, it is necessary to heat only the amorphous refractory 15 of the induction heating device 13 to 550 ° C. in order to promote the sintering of the irregular refractory.

At this time, before and after the start of the dissolution of the zinc ingot 12, it is preferable to rotate the curved duct 30 to change the hot air blowing direction.
For example, before the start of melting of the zinc ingot 12, the hot air blowing direction is set to the center part (zinc ingot 12) side of the pot 11, and the amorphous refractory 14 in the pot 11 and the amorphous refractory of the induction heating device 13. The object 15 is heated.
Then, after the zinc ingot 12 starts to melt, the hot air blowing direction is the induction heating device 13 side, and the amorphous refractory 15 of the induction heating device 13 is locally heated. Specifically, the temperature of the hot air is maintained at 550 ° C., each of the lids 35 to 37 is appropriately opened, the amorphous refractory 15 of the induction heating device 13 is 550 ° C., and the amorphous refractory 14 of the pot 11 is 460. ℃. This is because the runner 33 of the induction heating device 13 is the narrowest space, and this portion is reliably heated.

As described above, by using the drying heating equipment for plating pot and the drying heating method according to the present invention, the amorphous refractory 14 of the pot 11 and the amorphous refractory 15 of the induction heating device 13 are made uniform and objective. Therefore, the pot 11 can be continuously used in a continuous hot-dip galvanizing facility for a steel strip without performing repair work for the pot 11 or the like.

As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and the matters described in the scope of claims. Other embodiments and modifications conceivable within the scope are also included. For example, a case where a part or all of the above-described embodiments and modifications are combined to constitute the drying heating equipment and the drying method for the plating pot of the present invention is also included in the scope of the present invention.
Moreover, in the said embodiment, although the case where the amorphous refractory of the pot for plating provided with two induction heating apparatuses was dried was demonstrated, it is not limited to this, For plating of other structures A pot, for example, one or three or more (a plurality) induction heating devices may be provided.

DESCRIPTION OF SYMBOLS 10: Drying heating equipment of the pot for plating, 11: Pot, 12: Ingot, 13: Induction heating apparatus, 14, 15: Unshaped refractory, 15a: Drying heating apparatus, 16: Combustion gas generating means, 17: Dilution air Introduction means, 18: cylindrical object, 19: flame, 20: burner, 21: gas supply port, 22: air supply port, 23: gap, 24: outer cylinder, 25: butterfly valve (valve), 26: air intake Inlet, 27: mixing part, 28: leg, 29: duct, 30: curved duct, 31: brick, 32: coil, 33: runner, 34: plate, 35-37: lid, 38-40: opening, 41: Work table, 42, 43: Exhaust port

Claims (7)

In a state where metal ingots are stacked inside the pot, the indeterminate refractory disposed inside the pot and inside the induction heating device provided in communication with the pot is dried to continuously melt metal plating equipment It is a drying heating equipment of a pot for plating that can be used in
A drying heating equipment for a plating pot, comprising a drying heating device for guiding hot air obtained by diluting combustion gas generated by a burner with dilution air into the pot through a duct. 2. The drying heating equipment for a plating pot according to claim 1, wherein the drying heating device includes combustion gas generating means having a cylindrical object on the front side of the burner, and an outer periphery surrounding the cylindrical object with a gap. A cylinder is provided, an air inlet is provided on the base side of the outer cylinder via a valve, and has dilution air introduction means for introducing the dilution air, and the dilution air and the front side of the outer cylinder A drying heating equipment for a plating pot, characterized in that a mixing section with a combustion gas is provided. 3. The plating heating apparatus according to claim 1, wherein the temperature of the hot air is controlled by changing a mixing ratio of the dilution air to the combustion gas. 4. Pot heating and drying equipment. 3. The plating pot drying heating apparatus according to claim 1, wherein the temperature control of the hot air is performed by adjusting a combustion heat amount of the combustion gas. 4. Dry heating equipment. The drying heating equipment for a plating pot according to any one of claims 1 to 4, wherein a curved duct is rotatably provided at a portion inserted into the pot on the front side of the duct. Drying and heating equipment for plating pots. The drying heating equipment for a plating pot according to any one of claims 1 to 5 is used, the duct is moved, the direction in which the hot air is blown is changed, and the amorphous refractory of the induction heating device is locally applied. A method of drying and heating a pot for plating, characterized in that the heating is performed and / or the amorphous refractory of the pot is heated as a whole. The method for drying and heating a plating pot according to claim 6, wherein the temperature of the hot air is controlled to be lower than the melting point of the metal until the melting of the metal ingot is started, and after the melting of the metal ingot is started, A method for drying and heating a plating pot, wherein the temperature of the hot air is controlled within the range of the melting point of the metal (melting point + 200 ° C.).

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