Heating furnace simulation system

Abstract

To easily determine suitable control conditions in a heating furnace and reduce the number of tests with actual machines.SOLUTION: A simulation system (1) comprises: in-furnace temperature detectors (11, 12); a tray temperature detector (13); a temperature input part (16) to which measured in-furnace temperatures and measured tray temperatures are inputted; a condition input part (17) for set-inputting characteristic values including the mass and specific heat of a workpiece, the surface area of the workpiece in contact with an in-furnace atmosphere and the contact area in contact with a tray; a heat transfer coefficient set part (18) for setting a first heat transfer coefficient from the in-furnace atmosphere to the workpiece and a second heat transfer coefficient from the tray to the workpiece; a heating operation control part (19) for executing the heating operation of a verification heating furnace; a heating quantity calculation part (20) for calculating a heat quantity given to the workpiece from the in-furnace atmosphere and a heat quantity given to the workpiece from the tray, based on the measured in-furnace temperatures and the measured tray temperatures during the heating operation, and the characteristic values, the first and second heat transfer coefficients; and a temperature estimation part (21) for estimating a workpiece temperature based on the heat quantities calculated by the heat quantity calculation part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heating furnace simulation system for determining, through simulation processing using a verification heating furnace, the control conditions for placing a workpiece supported on a tray in a heating furnace and heating the workpiece at a target temperature. [Background technology]

[0002] Known examples of heating furnaces include curing furnaces used to heat and cure thermosetting sealants, adhesives, and the like in the manufacture of electrical and electronic components (see, for example, Patent Document 1). This curing furnace is configured with a hot air supply mechanism consisting of an electric heater and a fan device in the furnace body. Trays, each holding a large number of workpieces, are placed in multiple stages inside the furnace, and an operator sets the heating temperature to, for example, 150°C and the heating time to, for example, 30 minutes, and starts the heating process, whereby the heating process is carried out at the set temperature for the set time. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-227419 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned hardening furnace, the appropriate or sufficient heating time varies depending on the number of workpieces stored in the furnace, i.e., the number of trays, and the initial temperature inside the furnace when heating begins. Conventionally, the above-mentioned set temperatures and set times have been determined assuming the worst-case conditions, i.e., a sufficiently low initial temperature inside the furnace and a fully loaded furnace. However, setting the heating time under the worst-case conditions is inefficient and takes longer than necessary. Furthermore, when determining the set heating time, it is necessary to perform multiple tests in advance using the actual machine, resulting in a huge number of tests.

[0005] The present invention has been made in view of the above circumstances, and its object is to provide a heating furnace simulation system that can easily determine appropriate control conditions for a heating furnace and that enables a reduction in the number of tests using actual equipment. [Means for solving the problem]

[0006] In order to achieve the above object, the heating furnace simulation system (1) of the present invention is a system for accommodating a workpiece (6) supported on a tray (7) in a heating furnace and determining control conditions for heat-treating the workpiece at a target temperature by simulation processing using a verification heating furnace (2), and includes furnace temperature detection devices (11, 12) for measuring the ambient temperature in the verification heating furnace, a tray temperature detection device (13) for measuring the temperature of the tray in the verification heating furnace, a temperature input unit (16) into which the furnace temperature measured by the furnace temperature detection device and the tray temperature measured by the tray temperature detection device are input, and a mass and specific heat of the workpiece accommodated in the verification heating furnace at the time of verification, a surface area of ​​the workpiece in contact with the furnace atmosphere, The verification furnace includes a condition input unit (17) for setting and inputting characteristic values ​​including the contact area of ​​the workpiece in contact with the tray, a heat transfer coefficient setting unit (18) for setting a first heat transfer coefficient from the furnace atmosphere to the workpiece and a second heat transfer coefficient from the tray to the workpiece, a heating operation control unit (19) for executing the heating operation of the verification heating furnace during verification, a heat quantity calculation unit (20) for calculating the amount of heat imparted to the workpiece from the furnace atmosphere and the amount of heat imparted to the workpiece from the tray based on the measurement furnace temperature, the measurement tray temperature, the characteristic value, and the first and second heat transfer coefficients during the heating operation in the verification heating furnace, and a temperature estimation unit (21) for estimating the temperature of the workpiece based on the heat quantity calculated by the heat quantity calculation unit.

[0007] According to the above configuration, when performing a simulation process using a verification heating furnace, workpieces are placed in the verification heating furnace while supported on trays, and the heating operation control unit executes the heating operation of the verification heating furnace. At this time, the measured furnace temperature inside the furnace measured by the furnace temperature detection device and the measured tray temperature of the tray measured by the tray temperature detection device are input to the temperature input unit. This allows real-time sensing of temperature fluctuations in the verification heating furnace.

[0008] Furthermore, the condition input unit sets and inputs in advance characteristic values ​​including the mass and specific heat of the workpiece, the surface area of ​​the workpiece in contact with the furnace atmosphere, and the contact area of ​​the workpiece in contact with the tray. At the same time, the heat transfer coefficient setting unit sets a first heat transfer coefficient from the furnace atmosphere to the workpiece and a second heat transfer coefficient from the tray to the workpiece. The heat quantity calculation unit then calculates the amount of heat imparted to the workpiece from the furnace atmosphere and the amount of heat imparted to the workpiece from the tray based on the measured furnace temperature during the heating operation, the measured tray temperature, the respective characteristic values, and the first and second heat transfer coefficients. The temperature estimation unit estimates the workpiece temperature based on the heat quantity calculated by the heat quantity calculation unit.

[0009] Here, the amount of heat imparted to the workpiece per unit time is calculated by multiplying the difference between the temperature of the workpiece and the temperature of the object in contact with the workpiece (in this case, the ambient temperature in the furnace and the temperature of the tray) by the contact area of ​​the workpiece and the heat transfer coefficient of the object. The mass and specific heat of the workpiece are known values, and the temperature of the workpiece can be estimated from the integrated value of the amount of heat imparted to the workpiece. Therefore, based on the execution of the heating operation of the verification heating furnace, the current temperature of the workpiece and temperature changes can be simulated using various input information.

[0010] By making it possible to estimate the workpiece temperature in this way, it is possible to monitor whether the workpiece temperature reaches the target temperature and determine the appropriate heating time thereafter, enabling efficient heating processing. Furthermore, appropriate heating control conditions can be determined based on the conditions inside the furnace, such as the number of workpieces and the initial temperature inside the furnace. Furthermore, by determining the control conditions through simulation processing in this way, it becomes possible to extremely easily perform tests on an actual furnace. As a result, it is possible to easily determine appropriate control conditions for the heating furnace, which has the excellent effect of enabling a reduction in the number of tests on an actual furnace. The above-mentioned verification heating furnace may be one that operates in the same manner under the same conditions as the actual equipment, and may be prepared separately from the actual equipment, but it is also possible to use the actual equipment as the verification heating furnace for demonstration experiments. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing an embodiment of the present invention, and is a schematic diagram showing the overall configuration of a simulation system. [Figure 2] Block diagram showing the general functional configuration inside the PLC [Figure 3] A front view showing the inside of the hardening furnace used for verification [Figure 4] A diagram showing the external configuration of the curing furnace used for verification. [Figure 5] 1 is a diagram showing the state of workpiece temperature fluctuation over time for this embodiment (top) and a conventional example (bottom). DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment in which the heating furnace is applied to a curing furnace used in the manufacture of electrical and electronic components, etc., will be described with reference to the drawings. In this embodiment, the curing furnace as a heating furnace is used to heat and cure thermosetting sealants, adhesives, etc. in the manufacturing process of a workpiece, such as a sensor device. The heating furnace performs the heat treatment by setting control conditions such as a target heating temperature and a heating time to maintain the temperature after the target heating temperature is reached.

[0013] The simulation system 1 according to this embodiment is configured as a system for accommodating a large number of workpieces supported on trays in a hardening furnace, and determining the control conditions for heat-treating the workpieces at a target temperature through simulation processing using a verification hardening furnace 2 as a heating furnace for verification. Fig. 1 shows a schematic configuration of the simulation system 1 according to this embodiment. This simulation system 1 is configured with the verification hardening furnace 2 and a PLC 3 as a control device.

[0014] First, the configuration of the hardening furnace 2 used for verification will be briefly described with reference to Figures 3 and 4. As shown in Figures 3 and 4, the hardening furnace 2 includes a heating chamber 4 surrounded by a thermally insulated wall and a hot air supply mechanism 5 (see Figure 1) as a heating device. The heating chamber 4 has an entrance 4a at the front that is opened and closed by a thermally insulated door 4c (see Figure 4). Inside the heating chamber 4, i.e., inside the furnace, multiple metal trays 7 with multiple workpieces 6 placed on them are supported by supports (not shown) and stored in multiple layers one above the other. In addition, a bottom air passage 4b ​​is provided at the bottom of the heating chamber 4, extending left and right, and forming a circulating air passage together with the inside of the heating chamber 4.

[0015] As shown in Figure 3, the hot air supply mechanism 5 is composed of, for example, a blower fan 8 provided on the right wall of the heating chamber and an electric heater 9 provided in the bottom air duct 4b. This allows hot air to be circulated and supplied within the heating chamber 4, i.e., the oven, as indicated by the arrows in Figure 3. As shown in Figure 1, each mechanism of the curing oven 2 is controlled by a curing oven control device 10. Although this curing oven 2 is referred to as a verification oven, it is sufficient that it operates in the same manner as the actual oven under the same conditions and has a configuration similar to that of the actual oven. The actual oven itself can also be used as the verification oven for demonstration experiments, and of course, a separate oven can be prepared separately from the actual oven.

[0016] As shown in FIGS. 1 and 3, in the simulation system 1, thermocouples 11 and 12 are provided in the heating chamber 4 of the curing oven 2 as oven temperature detectors for measuring the ambient temperature, i.e., the air temperature, within the oven, and a tray thermocouple 13 is provided as a tray temperature detector for measuring the temperature of the tray 7. In this embodiment, the thermocouples 11 and 12 as oven temperature detectors are provided at multiple locations within the oven, in this case, at the upwind and downwind sides of the hot air. Hereinafter, when distinguishing between them, they will be referred to as the upwind thermocouple 11 and the downwind thermocouple 12. The tray thermocouple 13 is also provided at multiple locations, i.e., on each of the multiple trays 7.

[0017] As shown in FIG. 1, an upwind thermocouple 11, a downwind thermocouple 12, and multiple (only two shown) tray thermocouples 13 are connected to an I / O unit 14. The detection signals of these thermocouples 11-13, i.e., the air temperature inside the oven measured by the thermocouples 11 and 12, i.e., the measured oven temperature (Ta), and the temperature of the tray 7 measured by the tray thermocouple 13, i.e., the measured tray temperature (Tt), are input to the PLC 3. The PLC 3 is mainly composed of, for example, a computer, and is connected to an I / O device 15 that allows an operator or the like to input and output data from outside. The PLC 3 also outputs control signals to the curing oven control device 10.

[0018] The PLC 3, with its hardware and software configurations, executes a verification operation using the curing oven 2 and executes a simulation process using the information sensed during the verification operation. Specifically, as shown in Fig. 2, the PLC 3 has functions as a temperature input unit 16, a condition input unit 17, a heat transfer coefficient setting unit 18, a heating operation control unit 19, a heat quantity calculation unit 20, and a temperature estimation unit 21. Among these, the heating operation control unit 19 outputs a command to the curing oven control device 10 during verification, i.e., during simulation processing, to execute a heating operation for the curing oven 2.

[0019] During verification, the temperature input unit 16 receives input of the measurement furnace temperature (Ta [°C]) and the measurement tray temperature (Tt [°C]) from the IO unit 14. The condition input unit 17 receives input of a plurality of characteristic values ​​from the I / O device 15 based on the operation of the operator. Specifically, for the workpieces 6 housed in the hardening furnace 2 during verification, the number of workpieces placed, the total mass (m) and specific heat (c), the surface area of ​​the workpieces 6 in contact with the atmosphere in the furnace, i.e., the air (Sa [m2]), and the contact area of ​​the workpieces 6 in contact with the tray 7 (St [m2]) are set in advance as characteristic values.

[0020] The heat transfer coefficient setting unit 18 is configured to set a first heat transfer coefficient (ha [W / (m2 ·K]) from the furnace atmosphere, i.e., air, to the workpiece 6, and a second heat transfer coefficient (ht [W / (m2 ·K]) from the tray 7 to the workpiece 6. These heat transfer coefficients (ha, ht) may be determined theoretically, experimentally, or empirically, and set in advance by an operator. In this embodiment, the operator sets initial values, and then, if the initial values ​​are considered to be inappropriate during simulation processing, the heat transfer coefficient setting unit 18 adjusts the heat transfer coefficients (ha, ht).

[0021] The heat quantity calculation unit 20 calculates the heat quantity (Qa) imparted to the workpiece 6 from the air and the heat quantity (Qt) imparted to the workpiece 6 from the tray 7 based on the measurement furnace temperature (Ta) and measurement tray temperature (Tt) during the verification operation in the curing furnace 2, the characteristic values ​​(m, c, Sa, St), and the first and second heat transfer coefficients (ha, ht). The temperature estimation unit 21 estimates the workpiece temperature (Tw) based on the heat quantities (Qa, Qt) calculated by the heat quantity calculation unit 20. The calculation process for estimating the workpiece temperature at this time is repeatedly executed at predetermined time intervals, for example, at intervals of one second.

[0022] The temperature estimation unit 21 repeatedly estimates the current temperature (Sw) of the workpiece 6 based on the estimated workpiece temperature (Sw') at the time of the previous estimation, the amount of heat (Qa) from the air given to the workpiece 6 since the previous estimation, and the amount of heat (Qt) from the tray given to the workpiece 6 since the previous estimation. Furthermore, the PLC 3 is configured to calculate, based on the estimation by the temperature estimation unit 21, the time it takes for the workpiece 6 to rise to a set temperature, for example 150°C, depending on the thermal load, i.e., the number of workpieces 6, the number of trays 7, and the initial temperature inside the furnace, as appropriate control conditions for the actual heating furnace.

[0023] Next, the operation of the simulation system 1 configured as described above will be described with reference to FIG. 5. To perform a simulation process using the PLC 3 and the verification curing furnace 2, the operator places the required number of workpieces 6 on the tray 7 and places them in the heating chamber 4. At the same time, necessary numerical values, such as the number of trays, the number of workpieces 6, the mass (m) of the workpieces 6, the specific heat (c) of the workpieces 6, the surface area (Sa) of the workpieces 6 exposed to air, the contact area (St) of the workpieces 6 in contact with the tray 7, and initial values ​​of the first and second heat transfer coefficients (ha, ht), are input in advance via the input / output device 15. For example, the first heat transfer coefficient ha is set to 12, and the second heat transfer coefficient ht is set to 200. It is also possible to calculate the above numerical values ​​based on some of the necessary inputs.

[0024] When the input / output device 15 issues a command to start the verification operation, the PLC 3 causes the curing oven control device 10 to execute the heating operation via the heating operation control unit 19. During the heating operation, the PLC 3 inputs the measurement oven temperature (Ta) detected by the thermocouples 11 and 12 and the measurement tray temperature (Tt) detected by the tray thermocouple 13 to the temperature input unit 16 at predetermined time intervals, in this case, one second intervals. This allows real-time sensing of the air temperature inside the curing oven 2 and the temperature fluctuations of the tray 7. If the temperatures detected by the upwind thermocouple 11 and the downwind thermocouple 12 differ, the lowest temperature can be used for subsequent calculations. Similarly, if the temperatures detected by the multiple thermocouples 13 for the tray 7 differ, the lowest temperature can be used for subsequent calculations. Alternatively, the average value of the temperatures measured by the multiple thermocouples can be used.

[0025] Here, characteristic values ​​such as the mass m and specific heat c of the workpiece 6, the surface area Sa of the workpiece 6 in contact with the air inside the furnace, and the contact area St of the workpiece 6 in contact with the tray 7 are set and input in advance to the condition input unit 17. At the same time, a first heat transfer coefficient ha from the air inside the furnace to the workpiece 6 and a second heat transfer coefficient ht from the tray 7 to the workpiece 6 are set by the heat transfer coefficient setting unit 18. Then, the heat quantity calculation unit 20 of the PLC 3 calculates the heat quantity Qa that the workpiece 6 acquires from the air inside the furnace and the heat quantity Qt that the workpiece 6 acquires from the tray 7 based on the measured furnace temperature Ta, the measured tray temperature Tt, the characteristic values ​​(m, c, Sa, St), and the first and second heat transfer coefficients (ha, ht) during the heating operation.

[0026] The amount of heat Q given to the workpiece 6 is calculated as the sum of the amount of heat Qa given from the atmosphere inside the furnace, i.e., the air inside the furnace, and the amount of heat Qt given through the contact part of the tray 7. The relationship between the amount of heat Q given to the workpiece 6 and the temperature T of the workpiece 6 is as follows: Q=m*c*T The amount of heat given per unit time ΔQ' is expressed as follows, assuming the previous temperature is T': ΔQ′=H*S*(TT′) Since the amount of heat Q is Q=ΣΔQ′, if the work temperature is Tw, the amount of heat Qa given to the work 6 from the air inside the furnace can be calculated using the following equation (1). Qa=ha*Sa*(Ta-Tw) …(1) Similarly, the amount of heat Qa given to the workpiece 6 from the tray 7 is calculated by the following equation (2). Qt = ht * St * (Tt - Tw) … (2)

[0027] The temperature estimation unit 21 of the PLC 3 can estimate the temperature of the workpiece 6 from the integrated value of the heat quantity Q calculated by the heat quantity calculation unit 20. If the previous estimated workpiece temperature is Tw', the current workpiece temperature Tw can be calculated by the following equation (3). Tw=(Tw′*m*c+Qa+Qt) / (m*c) …(3) In this way, based on the simulation process using the hardening furnace 2, the current temperature Tw of the workpiece 6 and the state of temperature change can be simulated using various input information.

[0028] In this way, by making it possible to estimate the workpiece temperature Tw, it is possible to monitor whether the workpiece temperature Tw reaches a target temperature, for example, 150°C, and determine the appropriate holding time, i.e., heating time, for hardening from that point on. This enables efficient heat treatment in the control of an actual heating furnace. In this case, appropriate control conditions can be calculated based on the conditions inside the furnace, such as the number of workpieces 6 and the initial temperature inside the furnace. Furthermore, by determining the control conditions through simulation processing in this way, testing on an actual machine can be completed extremely easily.

[0029] Figure 5 shows the temperature change of the workpiece 6 over time when the workpiece 6 is cured in a heating furnace. The upper part shows the case where the control conditions are determined by the simulation process of this embodiment, and the lower part shows the conventional example, where the curing time is fixed at a constant value, e.g., 30 minutes. As is clear from Figure 5, the simulation process of this embodiment makes it possible to easily estimate the time it takes for the workpiece 6 to reach the target temperature, i.e., 150°C, depending on the conditions inside the furnace, i.e., the number of workpieces 6 and the initial temperature inside the furnace. This also makes it possible to set an appropriate holding time after the target temperature is reached, i.e., the heating time, which ultimately allows for a significant reduction in the overall heating time compared to the conventional example.

[0030] The heating furnace simulation system 1 of this embodiment can achieve the following effects. That is, the simulation system 1 of this embodiment is configured to use a verification curing furnace 2, sense the air temperature inside the curing furnace 2 and the temperature of the tray 7 in real time using multiple thermocouples 11-13, and estimate the workpiece temperature Tw based on calculating the amount of heat Qa imparted from the air inside the furnace to the workpiece 6 and the amount of heat Qt imparted from the tray 7 to the workpiece 6. As a result, appropriate control conditions for the heating furnace can be easily determined, making it possible to reduce the number of tests using actual equipment.

[0031] In particular, in this embodiment, the temperature estimation unit 21 is configured to repeatedly estimate the current work temperature Tw of the work 6 at predetermined time intervals based on the estimated work temperature Tw' at the time of the previous estimation, the amount of heat Qa from the furnace atmosphere given to the work 6 since the previous estimation, and the amount of heat Qt from the tray 7 given to the work 6 since the previous estimation. As a result, while the temperature Tw of the work 6 is estimated finely at predetermined time intervals, the amount of heat Qa given from the furnace air and the amount of heat Qt given from the tray 7 can each be determined with sufficient accuracy, and temperature estimation can be performed with sufficient accuracy.

[0032] In this embodiment, multiple thermocouples, in this case an upwind thermocouple 11 and a downwind thermocouple 12, are installed inside the furnace as furnace temperature detection devices, and the heat quantity calculation unit 20 uses the lowest of these multiple measured furnace temperatures for calculations. If variations in furnace temperature occur due to the structure of the heating furnace, there is a risk of insufficient heating occurring in locations with low furnace temperatures if calculations are performed using the measured furnace temperature measured at a high furnace temperature. However, in this embodiment, the lowest measured furnace temperature Ta among the multiple measured furnace temperatures is used, making it possible to prevent insufficient heating of the workpiece 6 depending on the location.

[0033] Furthermore, in this embodiment, the heat transfer coefficient setting unit 18 is configured to adjust the heat transfer coefficients ha and ht during the simulation process. By adjusting the heat transfer coefficients ha and ht while the simulation process is being performed, the simulation process can be performed while determining more accurate heat transfer coefficients ha and ht that match the actual conditions, thereby improving accuracy.

[0034] In the above embodiment, a curing furnace is used as a specific example of a heating furnace. However, the present invention can be applied to heating furnaces for various purposes, such as drying furnaces, reflow furnaces, and metal heat treatment furnaces. In this case, the workpieces can be various materials, not limited to electronic components such as sensors. The material of the tray is not limited to metal, but can be ceramic or the like. Various methods can be used as the heat source. In the above embodiment, a thermocouple is used as the temperature detection device, but various temperature measurement sensors can be used. Of course, one or three or more temperature detection devices can be provided in the furnace.

[0035] Furthermore, the specific numerical values ​​used in the calculations described in the above embodiments are merely examples and may be subject to various modifications. Furthermore, the heat transfer coefficients ha and ht may be fixed. While the present disclosure has been described based on examples, it is understood that the present disclosure is not limited to those examples or structures. The present disclosure also encompasses various modifications and variations within the scope of equivalents. Additionally, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and concept of the present disclosure.

[0036] The control unit and the method described herein may be implemented by a special-purpose computer configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and the method described herein may be implemented by a special-purpose computer configured by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and the method described herein may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible storage medium. [Explanation of symbols]

[0037] In the drawing, 1 is a simulation system, 2 is a curing furnace (verification heating furnace), 3 is a PLC, 4 is a heating chamber, 5 is a hot air supply mechanism, 6 is a workpiece, 7 is a tray, 11 and 12 are thermocouples (furnace temperature detection devices), 13 is a tray thermocouple (tray temperature detection device), 15 is an input / output device, 16 is a temperature input unit, 17 is a condition input unit, 18 is a heat transfer coefficient setting unit, 19 is a heating operation control unit, 20 is a heat quantity calculation unit, and 21 is a temperature estimation unit.

Claims

1. A system (1) for determining control conditions for heat-treating a workpiece (6) at a target temperature in a heating furnace by simulation processing using a verification heating furnace (2), the system comprising: an in-furnace temperature detection device (11, 12) for measuring the atmospheric temperature inside the verification heating furnace; a tray temperature detector (13) for measuring the temperature of the tray in the verification heating furnace; a temperature input unit (16) into which the oven temperature measured by the oven temperature detector and the tray temperature measured by the tray temperature detector are input; a condition input unit (17) for inputting and setting characteristic values ​​including the mass and specific heat of the workpiece placed in the verification heating furnace at the time of verification, the surface area of ​​the workpiece in contact with the atmosphere inside the furnace, and the contact area of ​​the workpiece in contact with the tray; a heat transfer coefficient setting unit (18) that sets a first heat transfer coefficient from the atmosphere inside the furnace to the workpiece and a second heat transfer coefficient from the tray to the workpiece; a heating operation control unit (19) that causes the verification heating furnace to perform a heating operation during verification; a heat quantity calculation unit (20) that calculates the amount of heat imparted to the workpiece from the atmosphere in the furnace and the amount of heat imparted to the workpiece from the tray based on the measurement furnace temperature, the measurement tray temperature, the characteristic value, and the first and second heat transfer coefficients during a heating operation in the verification heating furnace; and a temperature estimation unit (21) that estimates the temperature of the workpiece based on the heat quantity calculated by the heat quantity calculation unit.

2. 2. The heating furnace simulation system of claim 1, wherein the temperature estimation unit repeatedly estimates the current temperature of the workpiece at predetermined time intervals based on the estimated workpiece temperature at the previous estimation, the amount of heat given to the workpiece from the furnace atmosphere since the previous estimation, and the amount of heat given to the workpiece from the tray since the previous estimation.

3. 3. The heating furnace simulation system according to claim 1, wherein the furnace temperature detection devices are provided at a plurality of locations in the furnace and configured to measure temperatures at each location, and the heat quantity calculation unit performs calculations using the lowest temperature among the plurality of measured furnace temperatures.

4. 2. The heating furnace simulation system according to claim 1, wherein the heat transfer coefficient setting unit adjusts the heat transfer coefficient during the simulation process.

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