Intelligent gas flow regulation and control system for glass heating furnace

Abstract

An intelligent gas flow regulation and control system for a glass heating furnace comprises a gas pipeline system and a flow control system, the gas pipeline system comprises a main pipeline and a plurality of branch pipelines, and the flow control system comprises an upper computer, a PLC, a position sensor and a plurality of gas flow controllers. The gas flow controllers are respectively mounted on the main pipeline and the plurality of branch pipelines, and the upper computer and the PLC can control the gas flow of each branch pipeline, so that heat in the furnace can be quickly homogenized, and local control can be carried out as required according to actual processing requirements in the heating process of glass in the furnace; local control is based on processing technological parameter information of glass, the working state of a gas circuit is controlled in real time according to the position of the glass, the heating efficiency is further adjusted more finely, the quality of glass products is improved conveniently, and waste of electric quantity or energy consumption caused by invalid gas blowing in the area, away from the glass, in the heating furnace can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of glass heating, and in particular to a gas flow intelligent control system for a glass heating furnace. Background Art

[0002] Glass heating furnaces are usually equipped with a temperature control system that can compare the current temperature in the heating furnace with the target temperature in real time. If the temperature in the furnace is high, the heating will stop, and if the temperature in the furnace is low, the heating will start. The temperature difference between the various areas in the furnace cavity and the reciprocating motion in the furnace make the temperature of each area in the furnace gradually uniform, but this uniformity is poor, the adjustment ability is weak, and the heating efficiency is low, which leads to increased heating time of the glass and energy waste.

[0003] In order to improve the heating capacity of the heating furnace, a forced convection device is added. Through the high-temperature fans symmetrically arranged on both sides of the furnace body, the air in the heating furnace is forced to be stirred, and the temperature in various places in the furnace is quickly and evenly distributed, which effectively improves the temperature uniformity and heating efficiency in the furnace. At the same time, the heating time can be reduced. However, the high-temperature fans are expensive, and the convection range controlled by each high-temperature fan is large, which cannot achieve the requirement of accurately controlling the convection area according to processing needs.

[0004] In order to reduce equipment costs and improve heating efficiency and temperature uniformity in the furnace, some existing tempering furnaces use small-diameter pipelines to inject a small amount of compressed air into the heating furnace to forcibly enhance the convection effect in the furnace. However, this method can only control the opening or closing of the gas pipeline as a whole, but cannot regulate the gas flow injected into the heating furnace and the position of convection enhancement. It is impossible to accurately control the processing characteristics of the glass, which restricts the improvement of product quality. At the same time, during the heating process, the enhancement of convection in non-essential areas will cause energy waste. Summary of the invention

[0005] The present invention proposes a gas flow intelligent control system for a glass heating furnace to overcome the shortcomings of the prior art, and has good practicability and high economic benefits.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: A gas flow intelligent control system for a glass heating furnace, comprising a gas pipeline system and a flow control system, wherein the gas pipeline system comprises a trunk pipeline and a plurality of branch pipelines, and the flow control system comprises a host computer, a PLC controller, a position sensor, a trunk flow controller and a plurality of branch flow controllers; A trunk flow controller is installed on the trunk gas pipeline to control the on / off state and opening size of the trunk gas pipeline, so that the gas flow that can pass through the trunk pipeline is equal to the sum of the gas flow allowed to pass through all branch pipelines multiplied by the protection factor, so as to control the total air intake volume and air intake speed of the gas pipeline system and protect the branch pipelines; The air inlet end of the branch pipeline is connected to the main pipeline, and each branch pipeline is respectively installed with a branch flow controller for regulating the gas flow of each branch pipeline, and the main flow controller and the branch flow controller are both located outside the heating furnace; the branch pipeline extends to the inside of the heating furnace and is located above the lower heating furnace wire or below the upper heating furnace wire, and a plurality of air outlet holes are opened on the branch pipeline for blowing air into the heating furnace cavity to enhance convection in the furnace; The host computer pre-stores the position information of the area covered by each branch pipeline in the heating furnace. The position sensor can feed back the position of the glass in the heating furnace to the host computer in real time. The host computer pre-stores the glass size. The host computer can obtain the real-time coverage area of ​​the glass in the furnace according to the glass size and the position of the glass in the heating furnace, and then can obtain the reinforced area that needs to strengthen the heat exchange according to the glass properties, the temperature in the furnace and the heating state of the glass, as well as the degree of reinforcement required for each reinforced area; the host computer obtains the branch gas path located above or below the reinforced area by comparing the overlap between the reinforced area and the area covered by the branch pipeline. The host computer calculates the real-time gas flow required for the reinforced area according to the gas path diameter, the air outlet diameter and the number of air outlets of the branch pipeline, as well as the degree of reinforcement required for the reinforced area covered by the branch pipeline, and sends it to the PLC controller, and controls the main flow controller and the branch flow controller in real time through the PLC controller.

[0007] Preferably, the upper computer interface of the flow control system can set action parameters for the main flow controller and multiple branch flow controllers respectively, thereby controlling the on and off timing and duration of the main pipeline and multiple branch pipelines. The upper computer interface can also preset the gas flow curve according to the process requirements, and control the main flow controller and the branch flow controller in real time through the PLC controller according to the gas flow curve during the glass processing process.

[0008] Preferably, the branch pipeline includes a plurality of surround-type air outlet pipes arranged in a rectangular array at intervals, each surround-type air outlet pipe includes a plurality of straight pipes connected end to end in sequence, the plurality of straight pipes form a rectangular spiral surround structure, and air outlet holes are respectively provided on the plurality of straight pipes of the surround-type air outlet pipe.

[0009] Preferably, the branch pipeline includes a plurality of straight-through air outlet pipes, the straight-through air outlet pipes are parallel to the length or width direction of the heating area, the plurality of straight-through air outlet pipes are arranged parallel to each other and spaced apart, and a plurality of air outlet holes are opened on the straight-through air outlet pipes.

[0010] Preferably, the branch pipeline includes a plurality of segmented air outlet pipes, the segmented air outlet pipes are parallel to the length or width direction of the heating area, the plurality of segmented air outlet pipes are arranged in a rectangular array at intervals, and a plurality of air outlet holes are provided on the segmented air outlet pipes.

[0011] Preferably, the gas path arrangement in the furnace supports a combination of various styles.

[0012] Preferably, the diameter of each gas pipeline is variable.

[0013] Preferably, the length of each gas pipeline is variable.

[0014] Preferably, a plurality of air outlet holes are provided on each branch pipeline in the furnace, and the aperture and arrangement of the air outlet holes are variable.

[0015] Preferably, the system includes a gas preheating device, which can use compressed air or SO 2 gas.

[0016] According to the above technical solution, the beneficial effects of the present invention are: The present invention installs gas flow controllers on a main pipeline and multiple branch pipelines respectively, and can control the gas flow of each branch pipeline through a host computer and a PLC controller, which can not only quickly and evenly distribute the heat in the furnace, but also perform local control as needed according to actual processing requirements during the heating of the glass in the furnace. The local control controls the working state of the gas path in real time according to the position of the glass, so as to achieve the purpose of the gas path working where the glass goes, further and more finely adjust the heating efficiency, facilitate improving the quality of tempered glass, and avoid ineffective blowing in the area far away from the glass in the heating furnace to cause waste of electricity or energy, thereby realizing precise and intelligent regulation of the flow of heating gas according to the processing characteristics of the glass and the position of the glass in the heating furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the connection between the main pipeline and the branch pipeline; Figure 2 This is a schematic diagram of a branch pipeline in Embodiment 1; Figure 3 is a schematic diagram of a wraparound air outlet pipe according to Embodiment 1; Figure 4 This is a schematic diagram of the branch pipeline of Example 2; Figure 5 This is a schematic diagram of the branch pipeline of Example 3.

[0018] Markings in the figure: 1. main pipeline, 2. branch pipeline, 3. surround-type outlet pipe, 4. straight-through outlet pipe, 5. segmented outlet pipe, 6. branch flow controller, 7. outlet hole, 8. glass, 9. main flow controller. DETAILED DESCRIPTION

[0019] With reference to the accompanying drawings, the specific implementation is as follows: A gas flow intelligent control system for a glass heating furnace includes a gas pipeline system and a flow control system. The gas pipeline system includes a main pipeline 1 and multiple branch pipelines 2. The flow control system includes a host computer, a PLC controller, a position sensor, a main flow controller 9 and multiple branch flow controllers 6.

[0020] like Figure 1 As shown, a trunk flow controller 9 is installed on the main gas pipeline, which is used to control the on-off state and opening size of the main gas pipeline, so that the gas flow that can pass through the main pipeline 1 is equal to the sum of the gas flow allowed to pass through all branch pipelines 2 multiplied by the protection coefficient, so as to control the total air intake volume and air intake speed of the gas pipeline system and protect the branch pipeline 2.

[0021] like Figure 1 As shown, the air inlet end of the branch pipeline 2 is connected to the main pipeline 1, and each of the multiple branch pipelines 2 is equipped with a branch flow controller 6 for regulating the gas flow of the multiple branch pipelines 2 respectively. The main flow controller 9 and the branch flow controller 6 are both located outside the heating furnace, and an electromagnetic gas valve or a similar flow regulating device that is convenient for intelligent control can be used.

[0022] The branch pipeline 2 extends into the interior of the heating furnace and is located above the lower heating wire or below the upper heating wire. A plurality of air outlet holes 7 are provided on the branch pipeline 2 for blowing air into the heating furnace cavity to enhance convection in the furnace.

[0023] The upper computer has pre-stored glass size. The upper computer can obtain the real-time coverage area of ​​the glass in the furnace according to the glass size and the position of the glass 8 in the heating furnace, and then can obtain the reinforced area that needs to strengthen the heat exchange according to the glass properties, the temperature in the furnace and the heating state of the glass, as well as the degree of reinforcement required for each reinforced area.

[0024] The host computer obtains the branch gas path located above or below the reinforced area by comparing the overlap between the reinforced area and the area covered by the branch pipeline 2. Usually, multiple branch gas paths are numbered, and the host computer directly obtains the number of the branch gas path located above or below the reinforced area. The host computer calculates the real-time gas flow required for the reinforced area based on the gas path diameter of the branch pipeline 2, the diameter of the air outlet 7 and the number of the air outlet 7, and the degree to which the reinforced area covered by the branch pipeline 2 needs to be reinforced, and sends it to the PLC controller, and the PLC controller controls the trunk flow controller 9 and the branch flow controller 6 in real time.

[0025] The processing parameter information of the glass 8 includes the glass length, glass width, glass thickness, glass opening position and opening size. In addition, it is necessary to consider the impact of different glass film layers on the demand for heat exchange and the demand for heat exchange between the relative position of the gas path position and the glass position. The demand for heat exchange between the relative position of the gas path position and the glass position usually decreases from 1 to 0 from the center area of ​​the glass to the four corners. For a rectangular flat glass, when it is just put into the furnace, the area close to the center needs to open the branch flow controller 6 100%, the area around the center needs to open the branch flow controller 6 90%, and the outermost area to the edge only needs to open the branch flow controller 6 80%, so as to achieve the purpose of enhancing the heating effect of the middle area of ​​the glass. As the heating process continues, the branch flow controllers 6 of all areas will gradually close until the glass heating process is completed.

[0026] Through the host computer interface of the flow control system, the action parameters can be set for the main flow controller 9 and multiple branch flow controllers 6 respectively, so as to control the on and off timing and duration of the main pipeline 1 and multiple branch pipelines 2. The host computer interface can also preset the gas flow curve according to the process requirements, and control the main flow controller 9 and the branch flow controller 6 in real time through the PLC controller according to the gas flow curve during the glass processing process.

[0027] The upper computer interface can also preset a protection coefficient for the gas flow of the main pipeline 1. The gas flow of the main pipeline 1 is equal to the sum of the flow rates of all branch pipelines 2 multiplied by the preset protection coefficient, that is, the main line flow demand = sum (total main line flow demand) * protection coefficient, that is, the main flow controller 9 can further protect the entire gas pipeline system.

[0028] Embodiment 1: Figure 2 As shown, the branch pipeline 2 of this embodiment includes a plurality of surrounding air outlet pipes 3 arranged in a rectangular array. Figure 3 As shown, each wraparound air outlet pipe 3 includes multiple straight pipes connected end to end in sequence, and the multiple straight pipes form a rectangular spiral wraparound structure. The multiple straight pipes of the wraparound air outlet pipe 3 are respectively provided with air outlet holes 7.

[0029] like Figure 2 As shown in the figure, each dotted area represents a corresponding area of ​​a branch pipeline 2. The PLC controller will number multiple branch pipelines 2 in sequence in advance, and the glass will be Figure 2 Enter the heating area in the direction of the arrow in the figure. The PLC obtains the position of the numbered area of ​​the glass in the furnace in real time and feeds it back to the host computer. Every one or several seconds, the host computer analyzes the degree to which each position in the glass coverage area needs to enhance heat exchange, and on this basis obtains the gas flow requirements covering each position, that is, calculates the gas output of each outlet area separately. out n , n The region number.

[0030] in, x n It is the demand for heat exchange between the relative position of the gas path position and the glass position, decreasing from 1 to 0 from the center area of ​​the glass to the four corners; y n It is the coefficient of influence of glass thickness on heat exchange. Generally, thicker glass requires more heat exchange. z n It is the influence of different glass film layers on the demand for heat exchange. Non-coated glass can ignore this coefficient. The thermal conductivity of coated glass is inversely proportional to this coefficient, that is, the worse the heat absorption capacity of the glass, the stronger the heat exchange required, and the greater the coefficient. When there are openings on the glass, the airflow covering the area above or below the opening will also be reduced.

[0031] Embodiment 2: Figure 4 As shown, the branch pipeline 2 of this embodiment includes a plurality of straight-through air outlet pipes 4, which are parallel to the length or width direction of the heating area, and the plurality of straight-through air outlet pipes 4 are arranged in parallel and at intervals, and the branch flow controller 6 is connected to the straight-through air outlet pipes 4, and a plurality of air outlet holes 7 are opened on the straight-through air outlet pipes 4.

[0032] Embodiment 3: Figure 5 As shown, the branch pipeline 2 of this embodiment includes a plurality of segmented air outlet pipes 5, the segmented air outlet pipes 5 are parallel to the length or width direction of the heating area, the plurality of segmented air outlet pipes 5 are arranged in a rectangular array at intervals, the branch flow controller 6 is connected to the segmented air outlet pipes 5, and a plurality of air outlet holes 7 are opened on the segmented air outlet pipes 5.

[0033] In addition to the gas pipeline systems of embodiments 1, 2, and 3, the arrangement of the main pipeline 1 and multiple branch pipelines 2 also supports a variety of combined arrangements, and the diameter and length of each of the pipelines can be adjusted according to the glass processing requirements, and the diameter and number of the outlet holes 7 of the branch pipeline 2, as well as the arrangement of the outlet holes 7 on the branch pipeline 2 can also be changed and adjusted according to the glass processing requirements. In addition, the gas pipeline system also includes a gas preheating device, which can preheat the gas flowing into the gas pipeline system, and supports the use of compressed air, SO 2 And other gases.

[0034] Embodiments 1, 2, and 3 can all set the parameters of each intelligent gas flow controller through the host computer interface. The host computer saves the parameters and sends them to the PLC action execution mechanism. When the glass to be processed starts to enter the furnace, during the heating process in the heating furnace, according to the preset process parameters, the host computer controls the working status of each branch intelligent gas flow controller through the PLC, and adjusts the flow rate in real time, so as to improve heat exchange, increase the glass heating speed, and quickly and evenly reach a temperature close to the softening point.

Claims

1. A gas flow intelligent control system for a glass heating furnace, characterized in that: It comprises a gas pipeline system and a flow control system, wherein the gas pipeline system comprises a trunk pipeline (1) and a plurality of branch pipelines (2), and the flow control system comprises a host computer, a PLC controller, a position sensor, a trunk flow controller (9) and a plurality of branch flow controllers (6); A trunk flow controller (9) is installed on the trunk gas pipeline for controlling the on / off state and opening size of the trunk gas pipeline so that the gas flow rate that can pass through the trunk pipeline (1) is equal to the sum of the gas flow rates allowed to pass through all the branch pipelines (2) multiplied by the protection factor, so as to control the total gas intake volume and gas intake speed of the gas pipeline system and protect the branch pipelines (2); The air inlet end of the branch pipeline (2) is connected to the main pipeline (1); each of the plurality of branch pipelines (2) is provided with a respective branch flow controller (6) for regulating the gas flow of the plurality of branch pipelines (2); the main flow controller (9) and the branch flow controller (6) are both located outside the heating furnace; the branch pipeline (2) extends into the interior of the heating furnace and is located above the lower heating furnace wire or below the upper heating furnace wire; a plurality of air outlet holes (7) are provided on the branch pipeline (2) for blowing air into the heating furnace cavity to enhance convection in the furnace; The host computer pre-stores the position information of the area covered by each branch pipeline (2) in the heating furnace. The position sensor can feed back the position of the glass (8) in the heating furnace to the host computer in real time. The host computer pre-stores the glass size. The host computer can obtain the real-time coverage area of ​​the glass in the furnace according to the glass size and the position of the glass (8) in the heating furnace, and then can obtain the reinforced area that needs to strengthen the heat exchange according to the glass properties, the temperature in the furnace and the heating state of the glass, and the degree of reinforcement required for each reinforced area; the host computer obtains the branch gas path located above or below the reinforced area by comparing the overlap between the reinforced area and the area covered by the branch pipeline (2). The host computer calculates the real-time gas flow required for the reinforced area according to the gas path diameter of the branch pipeline (2), the diameter of the air outlet (7) and the number of the air outlet (7), and the degree of reinforcement required for the reinforced area covered by the branch pipeline (2), and sends it to the PLC controller, and the PLC controller controls the main flow controller (9) and the branch flow controller (6) in real time.

2. The gas flow intelligent control system for a glass heating furnace according to claim 1, characterized in that: The upper computer interface of the flow control system can be used to set action parameters for the main flow controller (9) and the plurality of branch flow controllers (6), respectively, so as to control the on-off timing and duration of the main pipeline (1) and the plurality of branch pipelines (2). The upper computer interface can also preset a gas flow curve according to process requirements, and in the glass processing process, the main flow controller (9) and the branch flow controller (6) can be controlled in real time through a PLC controller according to the gas flow curve.

3. The gas flow intelligent control system for a glass heating furnace according to claim 1, characterized in that: The branch pipeline (2) comprises a plurality of surround-type air outlet pipes (3) arranged at intervals in a rectangular array, each surround-type air outlet pipe (3) comprises a plurality of straight pipe sections connected end to end in sequence, the plurality of straight pipe sections forming a rectangular spiral surround structure, and air outlet holes (7) are respectively provided on the plurality of straight pipe sections of the surround-type air outlet pipe (3).

4. The gas flow intelligent control system for a glass heating furnace according to claim 1, characterized in that: The branch pipeline (2) comprises a plurality of straight-through air outlet pipes (4), the straight-through air outlet pipes (4) being parallel to the length or width direction of the heating area, the plurality of straight-through air outlet pipes (4) being arranged in parallel with each other and spaced apart, and a plurality of air outlet holes (7) being provided on the straight-through air outlet pipes (4).

5. The gas flow intelligent control system for a glass heating furnace according to claim 1, characterized in that: The branch pipeline (2) comprises a plurality of segmented air outlet pipes (5), the segmented air outlet pipes (5) being parallel to the length or width direction of the heating area, the plurality of segmented air outlet pipes (5) being arranged at intervals in a rectangular array, and the segmented air outlet pipes (5) being provided with a plurality of air outlet holes (7).

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