Annealing equipment and annealing method

Abstract

To provide an annealing apparatus which can suppress the generation of rust of a magnetic steel sheet caused by dew condensation.SOLUTION: An annealing apparatus (1) according to an embodiment comprises: a heating area (2) for heating a magnetic steel sheet (P); a cooling area (3) for cooling the magnetic steel sheet (P); a first shutter (4) arranged between the heating area (2) and the cooling area (3); a second shutter (5) provided at the cooling area (3) for carrying out the magnetic steel sheet (P) from the cooling area (3); and a third shutter (6) for dividing the cooling area (3) into plural rooms toward a conveyance direction of the magnetic steel sheet (P). While delivering a gas to a first room (R1) located between the second shutter (5) and the third shutter (6) and arranged on the side of the conveyance direction side of the magnetic steel sheet (P) in the plural rooms, the gas is exhausted from the first room (R1), and the magnetic steel sheet (P) is cooled by the gas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an annealing apparatus and an annealing method, and more particularly to an annealing apparatus and an annealing method for annealing an electromagnetic steel sheet by heating the electromagnetic steel sheet and then cooling the electromagnetic steel sheet. [Background technology]

[0002] Generally, electrical steel sheets are annealed to promote recrystallization and remove processing strain. For example, the annealing method described in Patent Document 1 involves passing an electric current through a cold-rolled steel sheet via an electric current-carrying roll to heat the cold-rolled steel sheet by Joule heat, and then spray-cooling the cold-rolled steel sheet with non-oxidizing gas in multiple zones. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-128651 Summary of the Invention [Problem to be solved by the invention]

[0004] The present applicant has found the following problem. Fig. 4 is a diagram showing a typical annealing apparatus. As shown in Fig. 4, a typical annealing apparatus 100 includes a preheating section 101, a main heating section 102, and a cooling section 103, and the preheating section 101, the main heating section 102, and the cooling section 103 are configured to be sealed by an openable / closable shutter 104.

[0005] In such an annealing apparatus 100, the electromagnetic steel sheet P is cooled in the cooling section 103 and then transported out, so when the shutter 104 on the transport side of the cooling section 103 is opened, outside air enters the inside of the cooling section 103 from the outside.

[0006] At this time, the air inside the cooling unit 103 is warmed by the residual heat of the electromagnetic steel sheets P, and is rapidly cooled by the intrusion of outside air into the cooling unit 103, which may cause condensation c inside the cooling unit 103. The condensation c may then adhere to the electromagnetic steel sheets P, causing rust on the electromagnetic steel sheets P.

[0007] The present disclosure has been made in consideration of such problems, and provides an annealing apparatus and an annealing method that can suppress the occurrence of rust on electrical steel sheets due to condensation. [Means for solving the problem]

[0008] An annealing apparatus according to one aspect of the present disclosure is an annealing apparatus that heats an electromagnetic steel sheet and then cools the electromagnetic steel sheet to anneal the electromagnetic steel sheet, a heating area for heating the electromagnetic steel sheet; a cooling area for cooling the electromagnetic steel sheet; a first shutter that is disposed between the heating area and the cooling area and that can be opened and closed; a second shutter that is provided in the cooling area and can be opened and closed to carry out the electromagnetic steel sheet from the cooling area; a third shutter that divides the cooling area into a plurality of rooms in the conveying direction of the electromagnetic steel sheet and that can be opened and closed; Equipped with Among the plurality of chambers, gas is supplied to a first chamber that is located between the second shutter and the third shutter and is closest to the conveying direction of the electromagnetic steel sheet, while the gas is exhausted from the first chamber, and the electromagnetic steel sheet is cooled by the gas.

[0009] An annealing method according to one aspect of the present disclosure is an annealing method for annealing an electromagnetic steel sheet by heating the electromagnetic steel sheet and then cooling the electromagnetic steel sheet, a heating area for heating the electromagnetic steel sheet; a cooling area for cooling the electromagnetic steel sheet; a first shutter that is disposed between the heating area and the cooling area and that can be opened and closed; a second shutter that is provided in the cooling area and can be opened and closed to carry out the electromagnetic steel sheet from the cooling area; when cooling the electromagnetic steel sheets in the cooling area by using an annealing apparatus including: a cooling area divided into a plurality of rooms in a conveying direction of the electromagnetic steel sheets; and a third shutter that can be opened and closed, With the second shutter and the third shutter closed, gas is supplied to a first chamber among the plurality of chambers that is located between the second shutter and the third shutter and closest to the conveying direction of the electromagnetic steel sheet, while the gas is exhausted from the first chamber to cool the electromagnetic steel sheet that has been conveyed to the first chamber. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to realize an annealing apparatus and an annealing method that can suppress the occurrence of rust on electrical steel sheets due to condensation. [Brief explanation of the drawings]

[0011] [Figure 1] 3A to 3C are diagrams for explaining the flow of annealing an electrical steel sheet using the annealing apparatus of the embodiment. [Figure 2] 3A and 3B are diagrams for explaining the flow of annealing an electrical steel sheet using the annealing apparatus of the embodiment. [Figure 3] FIG. 2 is a block diagram showing the configuration of a control system of the annealing apparatus according to the embodiment. [Figure 4] FIG. 1 is a diagram showing a general annealing apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0012] Specific embodiments to which the present disclosure is applied will be described in detail below with reference to the drawings. However, the present disclosure is not limited to the following embodiments. For clarity of explanation, a three-dimensional (XYZ) coordinate system will be used for explanation, and the following description and drawings will be simplified as appropriate.

[0013] First, the configuration of the annealing apparatus of this embodiment will be described. Figures 1(a) to 1(c) and 2(a) and 2(b) are diagrams for explaining the flow of annealing an electrical steel sheet using the annealing apparatus of this embodiment. Figure 3 is a block diagram showing the configuration of a control system of the annealing apparatus of this embodiment. Note that Figures 1(a) to 1(c) and 2(a) and 2(b) show simplified views of the annealing apparatus.

[0014] The annealing apparatus 1 of this embodiment is suitable for, for example, heating and then cooling and annealing electromagnetic steel sheets P used to form motor cores. In particular, the annealing apparatus 1 of this embodiment is suitable for, for example, annealing a plurality of core pieces C, each of which is made up of laminated electromagnetic steel sheets P punched out from a rolled steel sheet, while the core pieces C are placed on a conveying jig G1, as shown in Fig. 1(a). Here, the + side of the Y axis is the conveying direction of the conveying jig G1.

[0015] As shown in Figures 1(a) and 3, the annealing apparatus 1 includes a heating area 2, a cooling area 3, a first shutter 4, a second shutter 5, a third shutter 6, a fourth shutter 7, a fifth shutter 8, a conveying device 9, a first air supply device 10, a second air supply device 11, a first exhaust device 12, a second exhaust device 13, and a control device 14.

[0016] As shown in Fig. 1(a), the heating area 2 includes a preheating section 21 and a main heating section 22. As shown in Fig. 1(a) and Fig. 3, the preheating section 21 includes a preheating chamber 23 and a heating device 24. An inlet 23a is formed on the negative Y-axis side of the preheating chamber 23 for carrying in the transport jig G1. Furthermore, an outlet 23b is formed on the positive Y-axis side of the preheating chamber 23 for carrying out the transport jig G1.

[0017] The heating device 24 is not an essential part of the present disclosure and will not be described in detail, but it is possible to use a heating device that is generally used for heating the electromagnetic steel sheet P. When preheating the electromagnetic steel sheet P, the heating device 24 heats the inside of the preheating chamber 23 to a preheating temperature of about 200 to 450°C, for example.

[0018] As shown in Figures 1(a) and 3, the main heating section 22 includes a main heating chamber 25 and a heating device 26. The main heating chamber 25 is disposed on the +Y side of the preheating chamber 23. A carry-in entrance 25a is formed on the -Y side of the main heating chamber 25, through which the transport jig G1 is carried in, and the carry-in entrance 25a is continuous in the Y-axis direction with the carry-out exit 23b of the preheating chamber 23. In addition, a carry-out exit 25b is formed on the +Y side of the main heating chamber 25, through which the transport jig G1 is carried out.

[0019] The heating device 26 is not an essential part of the present disclosure and will not be described in detail, but it is possible to use a heating device that is generally used for heating the electromagnetic steel sheet P. When performing the main heating of the electromagnetic steel sheet P, the heating device 26 heats the inside of the main heating chamber 25 to a main heating temperature of about 450 to 600°C, for example.

[0020] As shown in Figures 1(a) and 3, the cooling area 3 includes a cooling chamber 31. The cooling chamber 31 is disposed on the +Y side of the main heating chamber 25. An inlet 31a is formed on the -Y side of the cooling chamber 31, through which the transport jig G1 is carried in, and the inlet 31a is continuous in the Y-axis direction with the outlet 25b of the main heating chamber 25. In addition, an outlet 31b is formed on the +Y side of the cooling chamber 31, through which the transport jig G1 is carried out.

[0021] 1(a), a first air supply port 31c, a second air supply port 31d, a first exhaust port 31e, and a second exhaust port 31f are formed in the cooling chamber 31. The first air supply port 31c is formed in the cooling chamber 31 to supply gas into the interior of the cooling chamber 31.

[0022] 1(a), the second air supply port 31d is disposed on the negative side of the Y axis relative to the first air supply port 31c, and is formed in the cooling chamber 31 to supply air into the cooling chamber 31. The first air supply port 31c and the second air supply port 31d may be formed, for example, in a portion on the negative side of the Z axis of the cooling chamber 31.

[0023] 1(a), the first exhaust port 31e is formed in the cooling chamber 31 to exhaust gas from the cooling chamber 31. The second exhaust port 31f is disposed on the negative side of the Y axis with respect to the first exhaust port 31e, and is formed in the cooling chamber 31 to exhaust gas from the cooling chamber 31.

[0024] 1(a), the first exhaust port 31e and the second exhaust port 31f may be formed on the +Z-axis side of the cooling chamber 31. In this case, the first exhaust port 31e may be positioned at a position offset in the Y-axis direction from the first air supply port 31c, and the second exhaust port 31f may be positioned at a position offset in the Y-axis direction from the second air supply port 31d.

[0025] 1(a), the first shutter 4 is disposed between the discharge outlet 25b of the main heating chamber 25 and the load entrance 31a of the cooling chamber 31, and opens and closes the discharge outlet 25b of the main heating chamber 25 and the load entrance 31a of the cooling chamber 31. The second shutter 5 opens and closes the discharge outlet 31b of the cooling chamber 31.

[0026] 1(a), the third shutter 6 is provided in the cooling chamber 31 to divide the cooling chamber 31 into a first chamber R1 and a second chamber R2. The third shutter 6 is disposed, for example, approximately in the center of the cooling chamber 31 in the Y-axis direction, and opens and closes to block or connect the first chamber R1 and the second chamber R2.

[0027] At this time, as shown in FIG. 1(a), a first air supply port 31c and a first exhaust port 31e are arranged in the first room R1, and a second air supply port 31d and a second exhaust port 31f are arranged in the second room R2.

[0028] 1(a), the fourth shutter 7 opens and closes the inlet 23a of the preheating chamber 23. The fifth shutter 8 is disposed between the outlet 23b of the preheating chamber 23 and the inlet 25a of the main heating chamber 25, and opens and closes the outlet 23b of the preheating chamber 23 and the inlet 25a of the main heating chamber 25.

[0029] 1(a), the first shutter 4, second shutter 5, third shutter 6, fourth shutter 7, and fifth shutter 8 are plates that are substantially parallel to the XZ plane and move in the Z-axis direction by the driving force of a driving device (not shown). However, the configuration of each shutter is not limited, and it is sufficient that the shutter is configured to be able to substantially seal each room.

[0030] The conveying device 9 conveys the conveying jig G1 to the + side of the Y axis. Since the conveying device 9 is not an essential part of the present disclosure, detailed description thereof will be omitted, but a conveying device 9 used in a general annealing device can be used, and the conveying device 9 extends in the Y axis direction so as to pass through, for example, the heating area 2 and the cooling area 3.

[0031] The first air supply device 10 is connected to the first air supply port 31c of the cooling chamber 31 and supplies gas to the first chamber R1 of the cooling chamber 31 through the first air supply port 31c. The second air supply device 11 is connected to the second air supply port 31d of the cooling chamber 31 and supplies gas to the second chamber R2 of the cooling chamber 31 through the second air supply port 31d. In this case, the gas may be an inert gas or dry air. The temperature of the gas may be such that it can cool the electromagnetic steel sheet P to approximately room temperature.

[0032] The first exhaust device 12 is connected to a first exhaust port 31e of the cooling chamber 31, and exhausts gas from the first chamber R1 of the cooling chamber 31 through the first exhaust port 31e. At this time, the first air supply device 10 and the first exhaust device 12 constitute a so-called push-pull type ventilation device. When cooling the electromagnetic steel sheet P, the inside of the first chamber R1 is cooled to a first cooling temperature of 200°C to room temperature by the first air supply device 10 and the first exhaust device 12.

[0033] The second exhaust device 13 is connected to a second exhaust port 31f of the cooling chamber 31, and exhausts gas from the second chamber R2 of the cooling chamber 31 through the second exhaust port 31f. At this time, the second air supply device 11 and the second exhaust device 13 constitute a so-called push-pull type ventilation device. When the electromagnetic steel sheet P is further cooled, the inside of the second chamber R2 is cooled to a second cooling temperature of about 200 to 600°C by the second air supply device 11 and the second exhaust device 13.

[0034] The control device 14 controls the heating device 24 of the preheating section 21, the heating device 26 of the main heating section 22, the first shutter 4, the second shutter 5, the third shutter 6, the fourth shutter 7, the fifth shutter 8, the conveying device 9, the first air supply device 10, the second air supply device 11, the first exhaust device 12, and the second exhaust device 13, for example, based on an annealing program that is preset to anneal the electromagnetic steel sheet P.

[0035] Next, a flow of annealing the electromagnetic steel sheet P using the annealing apparatus 1 of this embodiment will be described. Here, in the initial state when annealing of the electromagnetic steel sheet P starts, the first shutter 4, the second shutter 5, the third shutter 6, the fourth shutter 7, and the fifth shutter 8 are assumed to be closed.

[0036] The control device 14 controls and operates the heating device 24 of the pre-heating section 21, the heating device 26 of the main heating section 22, the first air supply device 10, the second air supply device 11, the first exhaust device 12, and the second exhaust device 13.

[0037] That is, the inside of preheating chamber 23 is maintained at a preset preheating temperature, and main heating chamber 25 is maintained at a preset main heating temperature. Also, gas is supplied to first chamber R1 of cooling chamber 31 while being exhausted from the first chamber R1, so that the inside of first chamber R1 is maintained at a first cooling temperature, and gas is also supplied to second chamber R2 of cooling chamber 31 while being exhausted from the second chamber R2, so that the inside of second chamber R2 is maintained at a second cooling temperature.

[0038] In this state, first, the control device 14 controls the fourth shutter 7 and the conveying device 9 to open the loading entrance 23a of the preheating chamber 23 and load the conveying jig G1 into the preheating chamber 23 through the loading entrance 23a, and then closes the loading entrance 23a of the preheating chamber 23 and preheats the electromagnetic steel sheet P in the preheating chamber 23.

[0039] Next, the control device 14 controls the fifth shutter 8 and the conveying device 9 to open the discharge outlet 23b of the preheating chamber 23 and the load entrance 25a of the main heating chamber 25, and loads the conveying jig G1 into the main heating chamber 25 through the discharge outlet 23b and the load entrance 25a, and then closes the discharge outlet 23b of the preheating chamber 23 and the load entrance 25a of the main heating chamber 25 to perform main heating on the electromagnetic steel sheet P in the main heating chamber 25.

[0040] Next, as shown in Figure 1(a), the control device 14 controls the first shutter 4 and the conveying device 9 to open the discharge outlet 25b of the main heating chamber 25 and the load entrance 31a of the cooling chamber 31, and conveys the conveying jig G1 into the second room R2 of the cooling chamber 31 through the discharge outlet 25b and the load entrance 31a.

[0041] Then, as shown in FIG. 1(b), the control device 14 controls the first shutter 4 to close the carry-out opening 25b of the main heating chamber 25 and the carry-in opening 31a of the cooling chamber 31, and the electromagnetic steel sheet P is cooled in the second chamber R2.

[0042] Next, as shown in Figure 1(c), the control device 14 controls the third shutter 6 and the conveying device 9 to connect the first room R1 and the second room R2 of the cooling chamber 31 and transport the conveying jig G1 into the first room R1.

[0043] 2(a), the third shutter 6 is controlled to isolate the first chamber R1 from the second chamber R2 of the cooling chamber 31, and the electromagnetic steel sheet P is cooled in the first chamber R1. At this time, the gas inside the first chamber R1 is exhausted from the first exhaust port 31e, so that it is possible to prevent heat from being trapped inside the first chamber R1 due to residual heat from the electromagnetic steel sheet P. In other words, it is possible to prevent the temperature of the gas inside the first chamber R1 from rising.

[0044] Next, as shown in Fig. 2(b), the control device 14 controls the second shutter 5 and the transport device 9 to transport the transport jig G1 out of the first chamber R1 of the cooling chamber 31. This allows the electromagnetic steel sheet P to be annealed.

[0045] At this time, since the temperature rise of the gas inside the first chamber R1 is suppressed as described above, even if outside air enters the first chamber R1 when the second shutter 5 is opened, the temperature difference between the gas inside the first chamber R1 and the outside air is smaller than in the general annealing apparatus 100 shown in Fig. 4, and it is possible to suppress the occurrence of condensation inside the first chamber R1. Moreover, when an inert gas or dry air is used as the gas, it is possible to further suppress the occurrence of condensation inside the first chamber R1.

[0046] In the annealing apparatus 1 and annealing method of the present embodiment, the gas inside the first chamber R1 is exhausted from the first exhaust port 31e when cooling the magnetic steel sheet P. This makes it possible to prevent heat from being trapped inside the first chamber R1 due to residual heat from the magnetic steel sheet P, and as a result, it is possible to prevent a rise in the temperature of the gas inside the first chamber R1.

[0047] As a result, even if outside air enters the first chamber R1 when the second shutter 5 is opened, the temperature difference between the gas temperature inside the first chamber R1 and the outside air is smaller than in the general annealing apparatus 100 shown in Fig. 4, and the occurrence of condensation inside the first chamber R1 can be suppressed. Therefore, the occurrence of rust on the electrical steel sheets P due to condensation can be suppressed. Moreover, when an inert gas or dry air is used as the gas, the occurrence of condensation inside the first chamber R1 can be further suppressed.

[0048] Furthermore, since the electromagnetic steel sheet P is cooled in the second chamber R2 before being cooled in the first chamber R1, the residual heat temperature of the electromagnetic steel sheet P in the first chamber R1 is lower than when the first chamber R1 and the second chamber R2 are integrally configured as in the general annealing apparatus 100 shown in FIG. 4, and the occurrence of condensation inside the first chamber R1 can be further suppressed.

[0049] Furthermore, in the annealing apparatus 1 and the annealing method of the present embodiment, the gas inside the second chamber R2 of the cooling chamber 31 is exhausted through the second exhaust port 31f, which prevents residual heat from being trapped inside the second chamber R2. Therefore, when the third shutter 6 is opened to load the transport jig G1 into the first chamber R1, it is possible to prevent a rise in temperature inside the first chamber R1. Therefore, the electromagnetic steel sheets P can be efficiently cooled.

[0050] 2(a), it is preferable that a new transport jig G2 is transported by the transport device 9 to the negative Y-axis side of the transport jig G1 so as to perform the previous process on the transport jig G1. This makes it possible, for example, to transport the transport jig G1 into the first chamber R1, close the third shutter 6, and cool the electromagnetic steel sheet P placed on the transport jig G1 in the first chamber R1, while opening the first shutter 4 and transporting a new transport jig G2 into the second chamber R2 through the carry-out port 25b of the main heating chamber 25 and the carry-in port 31a of the cooling chamber 31, and cool the electromagnetic steel sheet P placed on the new transport jig G2 in the second chamber R2. This makes it possible to improve the efficiency of the annealing process for the electromagnetic steel sheet P.

[0051] The present disclosure is not limited to the above-described embodiments, and can be modified as appropriate within the scope of the present disclosure. For example, although the cooling chamber 31 in the above embodiment is divided into the first chamber R1 and the second chamber R2, the number of divided chambers can be changed as appropriate. For example, the steps up to cooling the electromagnetic steel sheet P in the above embodiment are merely examples and can be modified as appropriate. For example, in the above embodiment, the electromagnetic steel sheets P that form the core pieces C are annealed, but the form of the electromagnetic steel sheets P is not limited. In addition, the transport form of the electromagnetic steel sheets P is not limited either. [Explanation of symbols]

[0052] 1 Annealing equipment 2 Heating Area 21 Preheating section 23 Pre-heating chamber, 23a Loading entrance, 23b Loading exit 24 Heating device 22 heating parts 25 main heating chamber, 25a loading port, 25b loading port 26 Heating device 3 Cooling area 31 cooling chamber, 31a loading entrance, 31b loading exit, 31c first air supply port, 31d second air supply port, 31e first exhaust port, 31f second exhaust port 4. First Shutter 5 Second Shutter 6 The Third Shutter 7 The Fourth Shutter 8 The Fifth Shutter 9. Conveyor equipment 10 First air supply device 11 Second air supply device 12 First exhaust device 13 Secondary exhaust system 14 Control device P Electrical steel sheet C Core piece R1 Room 1 R2 Second Room

Claims

1. An annealing apparatus that anneals an electromagnetic steel sheet by heating and then cooling the electromagnetic steel sheet, a heating area for heating the electromagnetic steel sheet; a cooling area for cooling the electromagnetic steel sheet; a first shutter disposed between the heating area and the cooling area and capable of being opened and closed; a second shutter that is provided in the cooling area and can be opened and closed to carry out the electromagnetic steel sheet from the cooling area; a third shutter that divides the cooling area into a plurality of rooms in the conveying direction of the electromagnetic steel sheet and that can be opened and closed; Equipped with a first chamber among the plurality of chambers that is located between the second shutter and the third shutter and closest to the side in the conveying direction of the electromagnetic steel sheet, while the gas is exhausted from the first chamber, and the electromagnetic steel sheet is cooled by the gas.

2. The annealing apparatus according to claim 1 , wherein the gas is an inert gas or dry air.

3. An annealing method for annealing an electromagnetic steel sheet by heating and then cooling the electromagnetic steel sheet, comprising: a heating area for heating the electromagnetic steel sheet; a cooling area for cooling the electromagnetic steel sheet; a first shutter disposed between the heating area and the cooling area and capable of being opened and closed; a second shutter that is provided in the cooling area and can be opened and closed to carry out the electromagnetic steel sheet from the cooling area; when cooling the electromagnetic steel sheets in the cooling area using an annealing apparatus comprising: a cooling area divided into a plurality of rooms in a conveying direction of the electromagnetic steel sheets; and a third shutter that can be opened and closed, an annealing method comprising: with the second shutter and the third shutter closed, supplying gas to a first chamber among the plurality of chambers that is located between the second shutter and the third shutter and closest to the side in a transport direction of the electromagnetic steel sheet, while exhausting the gas from the first chamber, thereby cooling the electromagnetic steel sheet transported to the first chamber.

4. When the electromagnetic steel sheet is cooled in the cooling area, a step of opening the first shutter while keeping the third shutter closed, transporting the electromagnetic steel sheet to a second chamber in the cooling area that is closer to the first shutter than the first chamber, and cooling the electromagnetic steel sheet there; a step of opening the third shutter while keeping the second shutter closed, and transporting the electromagnetic steel sheet to the first chamber; a step of cooling the electromagnetic steel sheet in the first chamber with the second shutter and the third shutter closed, while opening the first shutter and transporting a new electromagnetic steel sheet to the second chamber and cooling it therein; The annealing method of claim 3, comprising:

5. 5. The annealing method according to claim 4, wherein the new electrical steel sheet is cooled by exhausting the gas from the second chamber while supplying the gas to the second chamber.

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