Method and apparatus for heat treating corrugated sheets for air preheaters

Abstract

The application provides a heat treatment method and device for corrugated plates of an air preheater, wherein the device uses a first temperature detection camera to detect the temperature of the plate after induction heating, and selects different cooling schemes of mixed solutes and solutions according to the actually detected temperature and temperature difference value, sprays the cooling liquid with different concentrations according to the temperature difference of different regions, realizes the cooling of the temperature of each region to the same temperature in the same time, and obtains the uniform hardened layer as much as possible, and detects the temperature after cooling through a second temperature detection device to slightly adjust the concentration ratio of the subsequent cooling liquid. The method can greatly improve the cooling efficiency and effectively improve the uniformity of the hardened layer by configuring the concentration of the cooling liquid according to the actual temperature data obtained by the temperature detection camera, and the plate with excellent performance is obtained.

Description

Technical Field

[0001] This invention relates to the field of heat treatment technology for sheet metal surfaces, and specifically to a method and apparatus for heat treatment of corrugated sheets for air preheaters. Background Technology

[0002] During the operation of an air preheater, the quality of the corrugated plates used is particularly important. As the plates need to withstand high temperatures, vibrations will occur during use, and cracks may appear on the surface of the plates, resulting in air leakage and affecting the normal operation of the air preheater. To solve this problem, the surface of the plates can be hardened to increase its surface quality; the heat treatment method for its surface can be the more energy-efficient, green and efficient induction heating currently in use.

[0003] Furthermore, induction heating requires cooling. However, induction heating can cause skin effect and ring effect phenomena, and the unevenness of the corrugated sheet surface further contributes to uneven temperature distribution after heat treatment. While conventional cooling methods achieve a uniform cooling rate, the uneven temperature distribution results in inconsistent surface temperatures and an uneven hardened layer, negatively impacting the sheet's quality and performance. Therefore, there is an urgent need to research a new heat treatment method for corrugated sheets that can address the problem of poor sheet quality after heat treatment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a heat treatment method and apparatus for corrugated plates in air preheaters. The method employs a temperature detector to monitor the temperature of the plate after induction heating and selects different cooling schemes based on the actual detected temperature and temperature difference. Different concentrations of coolant are used for spray cooling to address the temperature differences in different areas, achieving uniform cooling of all areas to the same temperature within the same timeframe, resulting in a uniform hardened layer. This method, by configuring the coolant concentration based on the actual temperature data acquired by the temperature detection camera, significantly improves cooling efficiency, effectively enhances the uniformity of the hardened layer, and yields high-performance corrugated plates for air preheaters.

[0005] Specifically, the present invention provides a heat treatment method for corrugated plates of air preheaters, which includes the following steps:

[0006] S1. Detect the temperature of the board after heating:

[0007] The plate is induced to heat by an induction coil and moves forward at a speed of v0 under the traction of the lead screw guide. When the heated plate first reaches the spray range of the coolant spray device, the plate is divided into five areas according to the curvature characteristics of the irregular corrugated plate. The first temperature detection device starts to detect the temperature of each heated area, which is T.

[0008] S2. Configure coolant for each area:

[0009] Temperature data from each zone is transmitted to the central control room. The central control room determines the type of solute to be used in each zone and the amount of solute and solution required based on the temperature difference ΔT between the temperature T in each zone and the temperature T0 that the surface of the board needs to be cooled to. The central control room controls the closing and closing time of the three-way valve interface above the coolant mixing device in each zone based on the selection of solute and solution and the required concentration of coolant. The pump corresponding to the required solute and solution is turned on to deliver the corresponding amount of solute and solution to the coolant mixing tank.

[0010] The coolant configuration is determined based on the temperature difference ΔT between the temperature T in each zone and the required temperature T0 on the surface of the plate. When ΔT is within the low-temperature range 0-T... a When solute A and solution D are mixed, and ΔT is within the medium temperature range T... a -T b When solute B and solution D are mixed, and ΔT is within the high temperature range T... b -T c When mixing, solute C and solution D are selected. Let m be the required amount of solute, n be the required amount of solution, and Δp be the adjustment amount. The concentration ratio of the coolant is calculated according to the following formula:

[0011]

[0012] S3, Spray cooling plate:

[0013] After the required amount of coolant solute and solution has been delivered to the coolant mixing tank, the stirring rod starts to work to mix the solute and solution. After mixing is complete, the switch of the coolant spray device is turned on to spray the mixed coolant onto the surface of the board to cool it down.

[0014] S4. Measure the temperature of the board after cooling:

[0015] After the coolant spray has finished spraying the heated portion, the second temperature detection device detects the surface temperature T′ of each area of ​​the plate after cooling.

[0016] S5. Improve the accuracy of coolant concentration:

[0017] Store the surface temperature T′ of each region into the database. By comparing T′ with T0, adjust the amount of solute and solution in the coolant to improve the accuracy of the coolant concentration and achieve uniform cooling of the plate surface. S6. Repeat the above steps until the plate is completely heated and cooled.

[0018] Preferably, the temperature data acquired by the second temperature detection device is stored in a database, and when the temperature data T′ is different from the temperature T0 that the plate surface needs to be reduced to, the coolant concentration is optimized and corrected.

[0019] Preferably, when adjusting the coolant concentration, the temperature T0 to which the sheet surface needs to be reduced is set as a threshold value, and the value of Δp is determined according to ΔT′, where ΔT′ = T′ - T0; Δp = aΔT′, and a is the cooling coefficient of the coolant solute;

[0020] When T′ > T0, the next coolant concentration ratio is corrected to [(m + Δp) solute + (n - Δp) solution D]; when T′ < T0, the next coolant concentration ratio is corrected to [(m - Δp) solute + (n + Δp) solution D].

[0021] Another aspect of the present invention further provides a device for heat treatment of the corrugated plate of an air preheater, which includes a sheet, an induction heating device, a lead screw guide rail, a second temperature detection device, a coolant spraying device, a first temperature detection device, a waste coolant recovery tank, a three-way valve, a coolant mixing device, a console, a first check valve, a four-way valve, a four-category coolant introduction system, and a base. The sheet is fixed on the workbench above the guide rail, and an induction heating device, a coolant spraying device, a first temperature detection device, and a second temperature detection device are arranged above the sheet;

[0022] A waste coolant diversion groove is arranged on the workbench, and waste coolant recovery tanks are arranged at both ends of the waste coolant diversion groove;

[0023] The lower end of the base is placed on the workbench. The base includes a first-layer placement rack and a second-layer placement rack. A plurality of coolant mixing devices are arranged on the first-layer placement rack. The four-category coolant introduction system is connected to the plurality of coolant mixing devices by means of a four-way valve. The plurality of coolant mixing devices are connected to the water inlet system by means of a first check valve. A console is arranged on the second-layer placement rack;

[0024] The coolant mixing device includes a motor, a coolant mixing barrel upper cover, a coolant mixing barrel water level pipe, a coolant mixing stirring rod, a coolant mixing barrel, a second check valve, a coolant mixing device support, a coolant mixing finished product collection barrel, a coolant pipeline, a waste coolant collection barrel, and a third check valve. The motor is arranged at the upper end of the coolant mixing barrel upper cover, and the output shaft of the motor is connected to the coolant mixing stirring rod. The coolant mixing device support is provided with a coolant mixing barrel at the upper end and is connected to the coolant mixing finished product collection barrel at the lower end. The coolant mixing stirring rod is arranged inside the coolant mixing barrel. A water level pipe is arranged on one side of the coolant mixing barrel. The bottom of the coolant mixing barrel is connected to the coolant finished product placement barrel by means of a second check valve and is connected to the waste coolant collection barrel by means of a third check valve. The coolant finished product placement barrel and the waste coolant collection barrel are connected by means of a coolant pipeline;

[0025] All four types of coolant delivery systems include a coolant storage tank, a pump, and delivery piping;

[0026] The induction heating device is located behind the first temperature detection device, the coolant spray device is located between the first and second temperature detection devices, and the second temperature detection device is located in front of the coolant spray device.

[0027] Preferably, the camera of the temperature detection device and the nozzle of the coolant spray device are both placed on the crossbeam and can move along the crossbeam. A sliding groove is provided on the inner side between the first and second layer placement racks of the base, and the crossbeam can move up and down along the sliding groove.

[0028] Preferably, the water inlet system is divided into five branches, each connected to the first one-way valve above the five coolant mixing devices. The A, B, and C type coolant inlet system is divided into five branches, each connected to the A, B, and C ports of the four-way valve at the top of the five coolant mixing devices.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] (1) The method and apparatus of the present invention use a first temperature detector to detect the temperature of the plate after induction heating, and select different cooling schemes according to the actual detected temperature and temperature difference value. Different solutes and concentrations of coolant are configured for spray cooling for different temperature differences in different areas, so as to cool the temperature of each area to the same temperature in the same time, obtain a uniform hardened layer as much as possible, and improve the excellent performance of the plate.

[0031] (2) The method and apparatus of the present invention can select the most suitable coolant by controlling the four-way valve, thereby improving the cooling efficiency; by setting up a waste coolant diversion tank, the waste coolant is recycled into the tank, thereby realizing the reuse of waste coolant.

[0032] (3) The method and apparatus of the present invention detect the temperature after cooling through a second temperature detection device and adjust the concentration of the coolant for the next cooling cycle, which can greatly improve the accuracy of the coolant concentration, effectively improve the cooling efficiency of the coolant, and improve the uniformity of the hardened layer of the plate. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating the operation of the method of the present invention;

[0034] Figure 2 This is a schematic diagram of the overall structure of the device of the present invention;

[0035] Figure 3 This is a schematic diagram of the mixing device in the apparatus of the present invention;

[0036] Figure 4This is a partial schematic diagram of the mixing device of the present invention;

[0037] Figure 5 This is a partial schematic diagram of the device of the present invention;

[0038] Figure 6 This is a schematic diagram of the temperature detection device in the apparatus of the present invention.

[0039] Figure 7 This is a schematic diagram of the temperature detection device in the apparatus of the present invention.

[0040] The reference numerals in the attached figures are as follows:

[0041] 1-Sheet material; 2-Induction heating device; 3-Screw guide rail; 4-Second temperature detection device; 5-Coolant spray device; 6-First temperature detection device; 7-Waste coolant recovery tank; 8-Three-way valve; 9-Coolant mixing device; 901-Motor; 902-Coolant mixing tank cover; 903-Coolant mixing tank water level pipe; 904-Coolant mixing stirring rod; 905-Coolant mixing tank; 906-Second check valve; 907-Coolant mixing device bracket; 908- 909-Coolant Mixed Finished Product Collection Tank; 910-Coolant Pipeline; 911-Waste Coolant Collection Tank; 911-Third Check Valve; 10-Central Control Panel; 11-First Check Valve; 12-Four-Way Valve; 13-Class A Coolant Inlet System; 1301-Class A Coolant Inlet Pipeline; 1302-Class A Coolant Suction Pump; 1303-Class A Coolant Storage Tank; 14-Class B Coolant Inlet System; 15-Class C Coolant Inlet System; 16-Class D Coolant Inlet System; 17-Base. Detailed Implementation

[0042] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0043] It should be noted that in the description of this invention, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not mean that the device or element must have a specific orientation, or be constructed and operated in a specific orientation.

[0044] See appendix Figure 1 As shown, a heat treatment method for corrugated plates in an air preheater is provided, which includes the following steps:

[0045] S1. Detect the temperature of the board after heating:

[0046] The plate is induced to heat by an induction coil and moves forward at a speed of v0 under the traction of a lead screw and guide rail. When the heated plate first reaches the spray range of the coolant spray device, the plate is divided into five areas according to the characteristics of the irregular corrugated plate. The first temperature detection device starts to detect the temperature of each heated area, which is T.

[0047] S2. Configure coolant for each area:

[0048] Temperature data from each zone is transmitted to the central control room. The central control room determines the type of solute to be used in each zone and the required amount of solute and solution based on the temperature difference ΔT between the temperature T in each zone and the temperature T0 that the surface of the board needs to be cooled to. The central control room controls the closing and closing time of the three-way valve interface above the coolant mixing device in each zone according to the selection of solute and solution and the required concentration of coolant. The pump corresponding to the required solute and solution is turned on to deliver the corresponding amount of solute and solution to the coolant mixing tank.

[0049] S3, Spray cooling plate:

[0050] After the required amount of coolant solute and solution have been delivered to the coolant mixing tank, the stirring rod starts to work to mix the solute and solution. After mixing is complete, the coolant spray device is turned on to spray the mixed coolant onto the surface of the board to cool it down.

[0051] S4. Measure the temperature of the board after cooling:

[0052] After the coolant spray has finished spraying the heated portion, the second temperature detection device detects the surface temperature T′ of each area of ​​the cooled plate.

[0053] S5. Improve the accuracy of coolant concentration:

[0054] The surface temperature T′ of each region is stored in the database. By comparing T′ with T0, the amount of solute and solution in the coolant is adjusted to improve the accuracy of the coolant concentration and achieve uniform cooling of the plate surface.

[0055] S6. Repeat the above steps until all areas of the board have been heated and cooled.

[0056] Preferably, the coolant configuration is determined based on the temperature difference ΔT between the temperature T of each region and the temperature T0 that the plate surface needs to be lowered to. When ΔT is within the low temperature range 0-T... a When solute A and solution D are mixed, and ΔT is within the medium temperature range T... a -T b When solute B and solution D are mixed, and ΔT is within the high temperature range T... b -T cWhen inside, select solute C and solution D for mixing. Denote the required amount of solute as m, the amount of solution as n, and Δp as the adjustment amount. The concentration ratio of the coolant is calculated according to the following formula:

[0057] A corresponding cooling plan is constituted by the types of coolant solutes required in each region and the amounts of solute and solution required for configuration.

[0058] Preferably, the temperature data obtained by the second temperature detection device is stored in the database. When the temperature data T′ is different from the temperature T0 that the plate surface needs to drop to, the coolant concentration is optimized and corrected, so as to improve the accuracy.

[0059] When adjusting the coolant concentration, set the temperature T0 that the plate surface needs to drop to as the threshold value. The value of Δp is determined according to ΔT′, where ΔT′ = T′ - T0; Δp = aΔT′, and a is the cooling coefficient of the coolant solute;

[0060] When T′ > T0, the concentration ratio of the next coolant is corrected to [(m + Δp) solute + (n - Δp) solution D]. When T′ < T0, the concentration ratio of the next coolant is corrected to [(m - Δp) solute + (n + Δp) solution D].

[0061] The entire induction heating and cooling process is continuous. Before starting work, the positions of the cooling device and temperature detection should be adjusted to appropriate positions to ensure that it can cool to the specified area.

[0062] As Figures 2-7 shown, the present invention also proposes a device for heat treatment of the corrugated plate of an air preheater, including a plate 1, an induction heating device 2, a lead screw guide rail 3, a second temperature detection device 4, a coolant spraying device 5, a first temperature detection device 6, a waste coolant recovery tank 7, a three-way valve 8, a coolant mixing device 9, a console 10, a first one-way valve 11, a four-way valve 12, an A-type coolant introduction system 13, a B-type coolant introduction system 14, a C-type coolant introduction system 15, a D-type coolant introduction system 16, and a base 17. The plate 1 is fixed on the workbench above the guide rail, and an induction heating device, a coolant spraying device 5, a first temperature detection device 6, and a second temperature detection device 4 are arranged above the plate. The workbench is provided with a waste coolant diversion groove, and waste coolant recovery tanks 7 are arranged at both ends of the track. Five coolant mixing devices 9 are arranged on the second layer of the base placement rack. A console 10 is arranged at the rear end of the coolant mixing device 9. Four types of coolant introduction systems are arranged at the upper end of the console 10. The first one-way valve 11 connects the coolant mixing device 9 and the water inlet system. The four-way valve 12 connects the coolant mixing device 9 and the other four types of coolant introduction systems.

[0063] The coolant mixing device 9 includes a motor 901, a coolant mixing tank cover 902, a coolant mixing tank water level pipe 903, a coolant mixing stirring rod 904, a coolant mixing tank 905, a second one-way valve 906, a coolant mixing device bracket 907, a coolant mixed finished product collection tank 908, a coolant pipe 909, a waste coolant collection tank 910, and a third one-way valve 911. The motor 901 is placed on the upper end of the coolant mixing tank cover 902 and connected to the coolant mixing stirring rod. The coolant mixing tank is placed on the upper end of the coolant mixing device bracket 907 and connected to the coolant mixed finished product collection tank at the lower end. The coolant mixing stirring rod 904 is placed inside the coolant mixing tank 905. A water level pipe is provided on one side of the coolant mixing tank. The bottom of the coolant mixing tank is connected to the coolant finished product placement tank by the second one-way valve. The lower end of the coolant mixing tank is connected to the waste coolant collection tank by the third one-way valve. The coolant pipe connects the finished product placement tank and the waste coolant collection tank 910.

[0064] In this embodiment, the outer wall of the coolant mixing stirring rod 904 is provided with several layers of staggered stirring blades, and each layer is provided with at least three stirring blades. In order to improve the stirring efficiency, the cross section of the stirring blades can be set to an arc shape.

[0065] All four types of coolant introduction systems include a coolant storage tank, a pump, and introduction piping. The pump is located inside the coolant storage tank, and the introduction piping is connected to the pump. In this embodiment, the coolant storage tank is cylindrical; however, it can be configured as needed in other embodiments.

[0066] The induction heating device is located behind the first temperature detection device 6, the coolant spray device 5 is located between the first temperature detection device 6 and the second temperature detection device 4, and the second temperature detection device 4 is located in front of the coolant spray device 5.

[0067] The camera of the temperature detection device and the nozzle of the coolant spray device 5 are both placed on the cross frame and can move along the cross frame. The first and second layer placement racks of the base are provided with sliding grooves, and the cross frame can move up and down along the sliding grooves.

[0068] The water inlet system is divided into five branches, which are respectively connected to the first one-way valve 11 above the five coolant mixing devices. The A, B, and C type coolant inlet system is divided into five branches, which are respectively connected to the A, B, and C ports of the four-way valve 12 at the top of the five coolant mixing devices.

[0069] This invention employs a temperature detector to monitor the temperature of the sheet metal after induction heating. Based on the actual detected temperature and temperature difference, different cooling schemes are selected. Different types and concentrations of coolant are mixed to address the temperature differences in different areas. This mixture is then sprayed onto the sheet metal surface to cool all areas to the same temperature within the same timeframe, resulting in a more uniform hardened layer. Excess coolant is recovered using a coolant recovery tank and a waste coolant recovery trough 7, preventing waste. Furthermore, a second temperature detection device 4 monitors the temperature after cooling, providing feedback for adjusting the coolant concentration for the next cooling cycle. This significantly improves the accuracy of coolant concentration configuration, effectively increasing cooling efficiency and enhancing the uniformity of the hardened layer.

[0070] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A heat treatment method for corrugated plates in air preheaters, characterized in that: It includes the following steps: S1. Detect the temperature of the board after heating: The sheet material is induction heated by an induction coil, and then pulled by a lead screw and guide rail. v 0 Moving forward at a certain speed, when the heated plate first reaches the spray range of the coolant spray device, the plate is divided into five zones according to the curvature characteristics of the irregular corrugated plate. The first temperature detection device begins to detect the temperature of each heated zone, and the temperature is... T ; S2. Configure coolant for each area: Temperature data from each zone is transmitted to the central control room, which then adjusts the data according to the temperature of each zone. T The surface of the board needs to be cooled to a certain temperature. T 0 temperature difference ΔT The types of solutes used in each area and the required amounts of solute and solution are determined. The central control room controls the closing and closing time of the three-way valve interface above the coolant mixing device in each area according to the selection of solute and solution and the required concentration of coolant. The pumps corresponding to the required solute and solution are turned on to deliver the corresponding amount of solute and solution to the coolant mixing tank. The coolant configuration is based on the temperature of each zone. T The surface of the board needs to be cooled to a certain temperature. T 0 temperature difference ΔT To determine, when ΔT In the low temperature range 0-T a When mixing solute A and solution D, ΔT In the medium temperature range T a -T b When mixing solute B and solution D, ΔT In high temperature range T b -T c When mixing solute C and solution D, the required amount of solute is denoted as . m The volume of the solution is n , Δp To adjust the volume, the concentration ratio of the coolant is calculated according to the following formula: ； When adjusting the coolant concentration, the surface temperature of the plate needs to be reduced to a certain level. T 0 For the threshold, Δp The value is based on ΔT′ To determine, among which, ΔT′=T′-T 0 ; Δp= a ΔT′ , where a is the cooling coefficient of the solute in the coolant; when T′>T 0 Then, the coolant concentration ratio will be corrected to [( m + Δp ) solute + ( n - Δp Solution D], when T′ < T 0 Then, the coolant concentration ratio will be corrected to [( m - Δp ) solute + ( n + Δp Solution D]; S3, Spray cooling plate: After the required amount of coolant solute and solution has been delivered to the coolant mixing tank, the stirring rod starts to work to mix the solute and solution. After mixing is complete, the switch of the coolant spray device is turned on to spray the mixed coolant onto the surface of the board to cool it down. S4. Measure the temperature of the board after cooling: After the coolant spray has finished spraying the heated portion, the second temperature detection device measures the surface temperature of each area of ​​the cooled board. T′ ; S5. Improve the accuracy of coolant concentration: Surface temperature of each region T′ Store in the database, through T′ and T 0 By comparing the amounts of solute and solution in the coolant, the accuracy of the coolant concentration is improved, and the cooling uniformity of the plate surface is achieved. S6. Repeat the above steps until the entire board has been heated and cooled.

2. The heat treatment method for corrugated plates in air preheaters according to claim 1, characterized in that: The temperature data acquired by the second temperature detection device is stored in the database. When the temperature data... T′ The surface of the board needs to be cooled to a certain temperature. T 0 At the same time, the coolant concentration is optimized and corrected.

3. An apparatus for the heat treatment method of corrugated plate for air preheater as described in claim 1, comprising a plate, an induction heating device, a lead screw guide rail, a second temperature detection device, a coolant spraying device, a first temperature detection device, a waste coolant recovery tank, a three-way valve, a coolant mixing device, a central control panel, a first one-way valve, a four-way valve, a three-type solute coolant introduction system, a solution coolant introduction system, and a base, wherein the plate is fixed on a workbench above the guide rail and the induction heating device, the coolant spraying device, the first temperature detection device, and the second temperature detection device are provided above the plate; The workbench is equipped with a waste coolant guide channel, and waste coolant recovery tanks are provided at both ends of the waste coolant guide channel. The lower end of the base is placed on the workbench. The base includes a first layer of placement rack and a second layer of placement rack. Multiple coolant mixing devices are provided on the first layer of placement rack. The three types of solute coolant introduction system and solution coolant introduction system are connected to the multiple coolant mixing devices by means of a four-way valve. The multiple coolant mixing devices are connected to the water inlet system by means of a first one-way valve. A central control panel is provided on the second layer of placement rack. The coolant mixing device includes a motor, a coolant mixing tank cover, a coolant mixing tank water level pipe, a coolant mixing stirring rod, a coolant mixing tank, a second one-way valve, a coolant mixing device bracket, a coolant mixed product collection tank, a coolant pipeline, a waste coolant collection tank, and a third one-way valve. The motor is located at the upper end of the coolant mixing tank cover, and the output shaft of the motor is connected to the coolant mixing stirring rod. The coolant mixing tank is located at the upper end of the coolant mixing device bracket, and the coolant mixed product collection tank is connected at the lower end of the coolant mixing device bracket. The coolant mixing stirring rod is located inside the coolant mixing tank. A water level pipe is located on one side of the coolant mixing tank. The bottom of the coolant mixing tank is connected to the coolant mixed product placement tank via the second one-way valve and to the waste coolant collection tank via the third one-way valve. The coolant mixed product placement tank and the waste coolant collection tank are connected via a coolant pipeline. Both the solute coolant introduction system and the solution coolant introduction system include a coolant storage tank, a pump, and introduction pipelines; The induction heating device is located behind the first temperature detection device, the coolant spray device is located between the first and second temperature detection devices, and the second temperature detection device is located in front of the coolant spray device.

4. The apparatus for heat treatment of corrugated plates in an air preheater according to claim 3, characterized in that: The camera of the temperature detection device and the nozzle of the coolant spray device are both placed on the crossbeam and can move along the crossbeam. A sliding groove is provided on the inner side between the first and second layer of the base, and the crossbeam can move up and down along the sliding groove.

5. The apparatus for heat treatment of corrugated plates in an air preheater according to claim 3, characterized in that: The water inlet system is divided into five branches, which are connected to the first check valve above the five coolant mixing devices. The three types of solute coolant inlet system are divided into five branches, which are connected to the A, B and C ports of the four-way valves at the top of the five coolant mixing devices.

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