JPS6267118A - Method and apparatus for coating separating agent for annealing to electrical steel sheet - Google Patents

Abstract

PURPOSE:To prevent the generation of the state in which the amt. of a separating agent for annealing to be coated on the bottom surface of a steel sheet decreases according to the stop of a line by providing a spray device for coating an aq. slurry of the separating agent for annealing to the part of the bottom surface of the steel plate where the amt. of the separating agent to be coated on the bottom surface is below a reference value. CONSTITUTION:The spray device 11 having a tiltable spray nozzle 12 is provided between squeeze rolls 16 for coating the aq. slurry of the separating agent for annealing on the surface of the steel sheet and a drying furnace 7. The water in a piping from a selector valve set 13 up to the spray nozzle 12 is air-purged by a stop signal when the line stops in the operation for coating the separating agent for annealing to the steel sheet. The aq. slurry of the separating agent for annealing is then fed to the nozzle 12 and the nozzle 12 is erected to face the steel sheet and is thus kept standing by. A timer is operated by the signal for starting the reoperation of the line to spray the coating liquid from the nozzle 12 toward the part of the bottom surface of the steel sheet generated by the rolls 6 where the amt. of the separating agent to be coated decreases. The nozzle 12 is laid down after the spraying and is kept standing by for the next cycle after washing.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method and apparatus for applying an annealing separator to an electrical steel sheet suitable for preventing seizure of a grain-oriented electrical steel sheet during high-temperature annealing. .

[Prior Art] Generally, an annealing separator used to prevent seizure of steel sheets during high-temperature annealing is produced by suspending a suspension of the annealing separator in water at the exit of a continuous annealing furnace. On the side, the coating is applied to both the upper and lower surfaces of the steel plate using a squeeze roll to a predetermined thickness.

After the coated steel plate is dried with the annealing separator in a drying oven,
It is designed to be wound into a coil. FIG. 4 is a schematic diagram showing the above line configuration. In the figure, l is a decarburization annealing furnace, 2 is a deflector roll, 3 is a loop car, 4 is a priddle roll, 5 is a sprayer that supplies blood to the surface of the steel plate, 6 is a squeeze roll that squeezes the coating liquid to a predetermined thickness, 7 8 is a drying oven, and 8 is a take-up reel.

Regarding the annealing separator described in
As described in Japanese Patent No. 533, techniques using various refractory oxides (AM 203 , MgO, ZrO2, T + 02, etc.) are disclosed. Among these, as an annealing separator for grain-oriented electrical steel sheets, S
A scale layer containing MgO as a main component and the annealing separator undergo a solid phase reaction at a high temperature to facilitate the formation of a glassy film, and therefore a material containing MgO as a main component is often used. This glassy coating has an insulating property as a base for an insulating coating.
It is effective for

[Problem to be Solved by the Invention 1] By the way, #1-heavy work of the annealing separator reduces bending of the steel plate on the path to the take-up reel,
This is done at the outlet section of the line to prevent the annealing separator from falling off after drying. In this exit section, there is work to remove the coil that has been wound from the take-up reel, so line stoppages always occur.

Here, the squeeze roll is
The coating on the steel plate becomes loose or less, resulting in a particularly noticeable reduction in the amount of coating applied to the lower surface of the steel plate. If this coating amount is below the standard value, it will not be possible to obtain a high-quality product. FIG. According to FIG. 2, the amount of coating on the steel plate surface I- at one time when the line is stopped 1 is small (below the reference value) especially on the lower surface side before and after the point in contact with the squeeze roll (contact point). Is recognized.

In the conventional technology, in order to counter the above-mentioned decrease in the amount of application,
A method is used in which the steel plate is sent several meters in the opposite direction and then the line is operated normally, but due to this loss time, the line speed cannot be maintained high and the productivity of the line is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to prevent the occurrence of a decrease in the amount of coating on the lower surface of a steel plate due to line stoppage, and to improve the productivity of the line.

[Means for Solving the Problems 1] The method for applying an annealing separator to an electrical steel sheet according to the present invention involves applying an annealing separator to the electrical steel sheet before annealing the electrical steel sheet at a high temperature. In the method of applying an annealing separator, a water slurry of an annealing separator is applied to both the upper and lower surfaces of the steel plate using a squeeze roll, and then l - A water slurry of the annealing separator is applied using a spray device.

An apparatus for applying an annealing separator to an electrical steel sheet according to the present invention is an apparatus for applying an annealing separator to an electrical steel sheet that applies an annealing separator to an electrical steel sheet before annealing the electrical steel sheet at a high temperature. A squeeze roll is used to apply a water slurry of the annealing separator to both the upper and lower surfaces of the steel sheet, and a water slurry of the annealing separator is applied to the portion of the lower surface of the steel plate where the amount of the annealing separator applied is less than the standard value. , and a spray device disposed in the downstream process of the squeeze roll, and the spray device described in L includes:
- Equipped with a spray nozzle that can be inverted against the lower surface of the steel plate, and a switching valve set that can selectively supply slurry, water, or compressed air to the spray nozzle. be.

[Function] Generally, it is sufficient for the coating of an electrical steel sheet to be coated with an annealing separator such as MgO at a predetermined standard value or more. Therefore, according to the method for applying an annealing separator to an electrical steel sheet according to the present invention, a water slurry of annealing separator is applied to the lower surface of the steel sheet when the line is stopped, and the amount of water slurry applied to the lower surface of the steel sheet when the line is stopped. It is possible to prevent the occurrence of a reduction state and improve the productivity of the line.

Furthermore, according to the apparatus for applying an annealing separator to electrical steel sheets according to the present invention, the water slurry of the annealing separator can be prevented from clogging the piping when the line is stopped, and when the line is restarted, the annealing separator can be applied to the lower surface of the steel sheet. By applying the water slurry reliably, it is possible to prevent the occurrence of a decrease in the amount of coating on the lower surface of the steel plate due to line stoppage, and to improve the productivity of the line.

[Example] FIG. 1 is a schematic diagram showing an example of the present invention. This embodiment uses a squeeze roll 6 similar to that shown in FIG.
A spray device ift was placed between the drying oven 7 and the drying oven 7. The spray device 11 includes a spray nozzle 12 that can be inverted against the lower surface of the steel plate, and a switching valve cellar that can selectively supply one of wood slurry, water, and compressed air as an annealing separation agent to the spray nozzle 12. ) 13. 14 is a reserve tank for storing a water slurry of an annealing separation agent, 15 is a liquid sending pump, and 16 is a liquid receiver.

Next, the operation of this embodiment will be explained based on the driving pattern shown in FIG. In the initial state, spray nozzle 1
2 is set facing downward, and the area from the switching valve (cera) 13 to the spray nozzle 12 is filled with water. line stops] - Then, in response to the stop signal, an air purge is performed to expel the water in the piping from the switching valve set 13 to the spray nozzle 12, and then the coating liquid is sent to the spray nozzle 12. , the spray nozzle 12 is reversed (downward → "-") to face the steel plate and enters spray standby. The spray nozzle 12 performs start and end operations based on a timer operation based on a signal to restart the line.

After the spraying operation of the spray nozzle 12 is completed, the spray nozzle 12 is turned over again (from top to bottom) and washed with water, and in this state it enters standby for the next cycle. The reason for inverting the spray nozzle 12 as described above is to prevent water from splashing on the steel plate when washing the spray nozzle 12 with water. In addition, all time controls for air purge and spray washing can be performed by setting a timer.

Note that a water slurry of an annealing separator such as MgO tends to clog pipes when not being sprayed. Therefore, when not applying a water slurry of an annealing separator, the spray piping system is filled with water, and when spraying, the inside of the pipe is clogged. The tree is driven out by air purge, the pipe is filled with coating solution, and spraying begins.

According to the above embodiment, there is no need to reverse feed the steel plate several meters during operation after stopping, and the loss time of the line due to reverse feeding is reduced to 0, and as a result, the line speed is reduced from the conventional 50p to 60p. It was confirmed that it was possible to improve the temperature by about 20% to p■.

[Effects of the Invention] As described in -1- below, the method for applying an annealing separator to an electrical steel sheet according to the present invention includes the steps of:
In a method for applying an annealing separator to an electrical steel sheet, a water slurry of an annealing separator is applied to both lower surfaces of the steel sheet using a squeeze roll, and then the lower surface of the steel sheet is coated with an annealing separator. A water slurry of the annealing separator described in -1- is applied using a spray device to a portion where the amount of annealing separator applied is less than a reference value. Therefore, a water slurry of annealing separator is applied to the lower surface of the steel plate when the line is stopped, thereby preventing the occurrence of a state in which the amount of coating on the lower surface of the steel plate decreases due to line stoppage 11) and improving the productivity of the line. It becomes possible to

Further, the apparatus for applying an annealing separator to an electrical steel sheet according to the present invention is an apparatus for applying an annealing separator to an electrical steel sheet, which applies an annealing separator to the electrical steel sheet before subjecting the electrical steel sheet to high-temperature treatment-1-annealing. , a squeeze roll is used to apply a water slurry of the annealing separator to both sides of the lower surface of the steel plate, and a squeeze roll is used to apply the water slurry of the annealing separator to the lower surface of the steel plate where the amount of the annealing separator applied is less than the standard value. It has a spray device disposed after the squeeze roll so as to apply the slurry, and the spray device includes a spray nozzle that can be inverted against the lower surface of the steel plate, and a spray nozzle that sprays the slurry and water into the spray nozzle. , and a switching valve set that can selectively switch and supply either compressed air. Therefore, by preventing the annealing separator water slurry from clogging the piping when the line is stopped, and by reliably applying the annealing separator water slurry to the lower surface of the steel plate when the line is restarted, the lower surface of the steel plate due to the line stoppage can be prevented. Prevents the occurrence of reduced coating amount1
1-C, it is possible to improve the productivity of the line by r+7.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an embodiment of the present invention, and Fig. 2 is a steel plate surface I before and after the squeeze roll when the line is temporarily stopped.
FIG. 3 is a diagram showing an example of the operation pattern of the coating method according to the present invention, and FIG. 4 is a schematic diagram showing a conventional example. 6... Squeeze roll, 7... Drying oven, 11...
Spray device, 12... Spray nozzle, 13...
Cutting scale valve set. Agent Patent Attorney Osamu Shiokawa 2nd 12TIL-1□ o i,
2-One-way stop gate
Forward - Fig. 3 ■Air ('-ri Hl ■xi' = ■Nozzle report (bottom ()l) -! ■Special period μ----4 ■Spray !=■Nozzle report ()
yo-bottom) Washing with water -

Claims (2)

[Claims] (1) In a method for applying an annealing separator to an electrical steel sheet, in which an annealing separator is applied to the steel sheet before high-temperature finish annealing, a water slurry of an annealing separator is applied to the top and bottom surfaces of the steel sheet using a squeeze roll. An annealing separator for an electrical steel sheet, characterized in that after applying the annealing separator to the lower surface of the steel sheet, a water slurry of the annealing separator is applied using a spray device to a portion of the lower surface of the steel sheet where the amount of the annealing separator applied is less than a standard value. How to apply. (2) Apply an annealing separator to the electrical steel sheet before high-temperature finish annealing. In an annealing separator coating device for electrical steel sheets, a water slurry of an annealing separator is applied to both the upper and lower surfaces of the steel sheet. a squeeze roll; and a spray device disposed after the squeeze roll so as to apply a water slurry of the annealing separator to a portion of the lower surface of the steel sheet where the amount of annealing separator applied is less than a standard value. The spray device includes a spray nozzle that can be inverted against the lower surface of the steel plate, and a switching valve set that can selectively supply slurry, water, or compressed air to the spray nozzle. An apparatus for applying an annealing separator to an electrical steel sheet, comprising: