Device and method for improving reliability of thermocouple at channel cooling section in temperature rise stage

Abstract

The invention discloses a device and a method for improving the reliability of a thermocouple at a channel cooling section in a temperature rise stage, and belongs to the technical field of substrate glass manufacturing. The device effectively solves the problem of fixing the thermocouple by forming a notch in a thermocouple piece and arranging the thermocouple in the notch of a groove-shaped structure, so that the reliability of the thermocouple is improved. And the device is more stable and reliable in the use process. The notch is bent upwards, so that a local cavity is formed between the interior of the notch and the cooling pipe body, and the cavity structure is enough for flexible movement of a thermocouple temperature measurement spot welding point. The position of a temperature measuring point of the thermocouple is crucial to the accuracy of a measuring result. According to the device, the root of the thermocouple (the temperature measuring point of the welding type thermocouple) is accurately arranged in the notch, so that good contact between the temperature measuring point and a measured object is ensured, and the temperature measuring accuracy is improved. Through the sliding thermocouple structure, the problem of large-area damage of the top thermocouple in the temperature rise stage is solved, and the reliability of the thermocouple is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of substrate glass manufacturing, and relates to a device and a method for improving the reliability of a thermocouple in a channel cooling section during a heating stage. Background Art

[0002] The hot end technology of substrate glass is the core part of its preparation. Each functional area has its own different process settings. Generally, the internal temperature of most areas of the main body reaches above 1400℃ and needs to operate stably for a long time. Thermocouples are important basic components for temperature monitoring and process control of hot end equipment. Different numbers and points are often designed according to the different structures and materials of each functional section. Generally, in the high temperature zone, that is, the process interval above 1600℃, the thermocouples are mainly concerned with the oxidation and volatilization of materials under long-term operation, while the low temperature zone is relatively stable, and most of them can achieve a lifespan of more than 4 years. At the top of the cooling section in the low temperature zone, a certain number of thermocouples are set. This type of thermocouple is mainly used to monitor the flow and temperature of the glass liquid finally supplied to the molding area, but these thermocouples often suffer a large proportion of damage during the heating stage. After statistical analysis of multiple lines, the basic law of thermocouple damage in this area is sorted out, that is, it mainly occurs in the late stage of heating, and the temperature is mostly concentrated between 900℃ and 1200℃, and compared with other parts, it is obviously concentrated damage. Through mechanism analysis, it is basically clear that the damage of the thermocouple at the top of the cooling tube is related to the collapse deformation and axial expansion displacement of the cooling tube body during the high-temperature empty tube stage. Since the molten glass has not yet filled the tube body at this time, the tube body material gradually softens under the action of high temperature, and a slow creep collapse occurs. Combined with the influence of axial expansion at the same time, a large local displacement movement is formed. In addition, the thermocouple at the top cannot move freely because it is sintered with the filling layer, causing local stress and reaching the tensile limit. Therefore, for the thermocouple at the top of the cooling tube, at the current stage, when the strength of the thermocouple wire itself is difficult to significantly increase, the main solution to this problem is to maintain the mobility of the thermocouple wire so that it has the ability to release tensile stress at a certain distance. Summary of the invention

[0003] The purpose of the present invention is to solve the problems in the prior art and to provide a device and method for improving the reliability of thermocouples in a channel cooling section during the heating stage.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a device for improving the reliability of a thermocouple in a channel cooling section during a temperature rise stage, comprising a thermocouple and a thermocouple sheet installed on a cooling pipe body; A notch with a slot-shaped structure is provided on the thermocouple sheet, a cavity is formed between the notch and the cooling tube body, the root of the thermocouple is arranged in the cavity, and the root of the thermocouple is the temperature measuring point of the welding type thermocouple.

[0005] Preferably, ceramic fiber cloth is provided above the thermocouple sheet.

[0006] Preferably, the surface area of ​​the ceramic fiber cloth is greater than the surface area of ​​the thermocouple sheet.

[0007] Preferably, a filling material is provided above the ceramic fiber cloth.

[0008] Preferably, the notch is a rectangular gap, the gap width is greater than 1.2 to 1.5 times the diameter of the thermocouple, and the gap width is smaller than the diameter of the temperature measuring point.

[0009] Preferably, the length of the notch ranges from 20 mm to 50 mm.

[0010] Preferably, there are a plurality of thermocouple sheets, and each thermocouple sheet is provided with a notch.

[0011] Preferably, a plurality of notches are provided on the thermocouple sheet.

[0012] Preferably, the thermocouple piece is welded to the cooling tube body.

[0013] The present invention provides a method for improving the reliability of a thermocouple in a channel cooling section during a heating stage, comprising: The thermocouple sheet is installed on the cooling tube body, and the thermocouple is placed in the notch on the thermocouple sheet. The notch with a groove structure allows the thermocouple to have displacement release when the cooling section expands or collapses, thereby improving the reliability of the channel thermocouple.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a device for improving the reliability of the thermocouple in the channel cooling section during the heating stage. Since the traditional thermocouple may not be firmly fixed in the application scenario, it is easy to be displaced or damaged by external forces. The device effectively solves the problem of fixing the thermocouple by opening a notch on the thermocouple sheet and setting the thermocouple in the notch of the groove structure, making it more stable and reliable during use. The notch is bent upward, so that a local cavity is formed between its interior and the cooling tube body. The cavity structure must be sufficient for the flexible movement of the thermocouple temperature measuring point welding point. The position of the thermocouple temperature measuring point is crucial to the accuracy of the measurement result. The device accurately sets the root of the thermocouple (the temperature measuring point of the welded thermocouple) in the notch, ensuring good contact between the temperature measuring point and the object to be measured, and improving the accuracy of the temperature measurement. Through the sliding thermocouple structure, the problem of large-area damage to the top thermocouple in the heating stage is solved, and the reliability of this type of thermocouple is improved.

[0015] Furthermore, the root surface of the thermocouple is covered with protective ceramic fiber cloth to keep the root of the thermocouple movable and not affected by the sintering of surrounding fillers.

[0016] Furthermore, the length of the notch is determined to be in the range of 20mm to 50mm according to the actual expansion and collapse amounts. If it is too small, sufficient displacement release cannot be achieved. If it is too large, local deformation may cause local deformation of the cooling pipe body, resulting in bending of the thermocouple sliding path, affecting the release of displacement. The same thermocouple monitoring points are also set in the adjacent area.

[0017] Furthermore, before laying, a gap of the same size as the slot-shaped notch needs to be opened on the ceramic fiber cloth to ensure that the internal couple wire can extend from the gap and has the ability to protect the movement of the thermocouple sheet and the thermocouple temperature measurement point below. The area of ​​the ceramic fiber cloth is larger than that of the thermocouple sheet, so the entire area of ​​the thermocouple sheet can be covered.

[0018] Furthermore, ceramic fiber cloth has the characteristics of high temperature resistance, heat insulation, and insulation. It can effectively block the direct impact of the external high temperature environment on the thermocouple and thermocouple piece, prevent the thermocouple from being damaged due to excessive temperature, and ensure the accuracy and stability of its measurement. Ceramic fiber cloth can also play a certain buffering role, reduce the damage of external shock and vibration to the thermocouple and thermocouple piece, and extend its service life.

[0019] Furthermore, the ceramic fiber cloth combined with the filling material can form a good thermal insulation layer. This helps to reduce the heat loss of the cooling tube body and improve energy efficiency, while also preventing the temperature changes in the surrounding environment from interfering with the temperature measurement of the cooling tube body. The filling material is filled on top of the ceramic fiber cloth to fix and compact it. It can make the ceramic fiber cloth fit more closely to the thermocouple sheet and the thermocouple to prevent it from loosening or shifting, ensuring that the thermocouple is always in the correct measurement position. The filling material can also increase the stability of the entire device, reduce shaking or vibration caused by external factors, and further improve the reliability of temperature measurement.

[0020] Furthermore, the width of the rectangular slit is greater than 1.2 to 1.5 times the diameter of the thermocouple, so that the thermocouple can be easily placed in the notch. The width of the slit is smaller than the diameter of the temperature measuring point, and this design can effectively prevent the temperature measuring point from slipping out of the notch.

[0021] Furthermore, multiple thermocouples and multiple notches on each thermocouple can be used to arrange thermocouples at different positions, so that different areas of the cooling pipe body can be covered more comprehensively and more accurate temperature distribution information can be obtained. This can avoid measurement errors caused by the limitations of a single temperature measurement point and provide more reliable temperature data for the operation and control of the equipment. If a thermocouple in a thermocouple or notch fails, other thermocouples and thermocouples in the notch can continue to work, thereby reducing the impact of a single thermocouple failure on the entire temperature measurement system. This redundant design improves the reliability and stability of the device and ensures that the temperature can be continuously and accurately measured during long-term operation. In different working scenarios, it may be necessary to focus on monitoring different parts of the cooling pipe body, or to perform more detailed measurements based on the characteristics of temperature changes. The design of multiple thermocouples and notches can flexibly adjust the layout position and number of thermocouples to meet different working conditions and requirements. When the thermocouple needs to be maintained or replaced, the problematic thermocouple or thermocouple in the notch can be selected for processing without affecting the normal operation of other parts. This design makes maintenance work more convenient and quick, reducing equipment downtime and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 It is a cross-sectional view of the root of the thermocouple of the present invention.

[0024] Figure 2 The invention discloses a thermocouple structure with a groove-shaped notch.

[0025] Figure 3 It is a device structure diagram of the reliability of the thermocouple in the cooling section of the lifting channel of the present invention during the heating stage.

[0026] Figure 4 This is the thermocouple temperature measuring point movement and stress release principle of the present invention.

[0027] Among them: 1-cooling tube body, 2-thermocouple sheet, 3-welding point, 4-thermocouple, 5-notch, 6-ceramic fiber cloth, 7-filling material. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0031] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0032] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings: The present invention proposes a device for improving the reliability of the thermocouple in the channel cooling section during the heating stage, such as Figures 1 to 4 As shown, it includes a thermocouple 4 and a thermocouple sheet 2 installed on a cooling tube body 1; a notch 5 with a groove structure is opened on the thermocouple sheet 2, a cavity is formed between the notch 5 and the cooling tube body 1, and the root of the thermocouple 4 is set in the cavity, and the root of the thermocouple 4 is the temperature measuring point of the welded thermocouple.

[0035] A ceramic fiber cloth 6 is provided above the thermocouple sheet 2, and a filling material 7 is provided above the ceramic fiber cloth 6. The surface area of ​​the ceramic fiber cloth 6 is greater than the surface area of ​​the thermocouple sheet 2. The thermocouple sheet 2 is welded to the cooling pipe body 1 through a welding spot 3. The notch 5 is a rectangular gap, the gap width is greater than 1.2 to 1.5 times the diameter of the thermocouple 4, and the gap width is less than the diameter of the temperature measuring point. The length of the notch 5 ranges from 20 mm to 50 mm.

[0036] The number of thermocouples 2 and notches 5 can be designed in the following forms: 1) there are several thermocouple pieces 2, and each thermocouple piece 2 is provided with a notch 5; 2) several notches 5 are provided on the thermocouple piece 2.

[0037] Specifically, refer to Figure 1 , is a cross-sectional view of the root of the thermocouple. The cooling tube body 1 is the functional section of the equipment that needs to be monitored by the thermocouple of the present invention. It is a precious metal pipe through which the glass flows. The cross-section is a flat tube with a nearly elliptical shape. The main function of the cooling section is to achieve a large heat dissipation area through this structure and improve the overall heat dissipation efficiency. This is also the main function of the cooling section. It is precisely because of this special-shaped structure of the cooling section that the supporting effect of the top of the tube body is limited. Therefore, often in the heating stage, since the glass liquid has not flowed in temporarily, there is no effective support for it. When the temperature reaches above 600°C, the top of the tube body will slowly collapse and deform, and as time goes by and the temperature continues to rise, the collapse of the tube body tends to accelerate. At the same time, the high temperature also causes the cooling tube body to expand synchronously along the axial length direction. The movement of the above two flat tubes jointly promotes a large displacement of a point in the top area of ​​the cooling section body 1.

[0038] In summary, there are three main ideas to solve the problem of top thermocouple tensile fracture caused by flat tube collapse and expansion. The first is to optimize the structural strength and high temperature stability of the cooling tube body 1 through manufacturing or material processing, which has certain technical difficulties, mainly due to the industry-specific process and product performance requirements, and strict index requirements for materials; the second is to improve the strength of the thermocouple itself so that it has sufficient tensile strength. Considering the size limitations of the welded thermocouple wire and the external protection device, as well as the reverse tensile damage that excessive strength may cause to the cooling tube body 1, the strength of the thermocouple wire can only be improved by a small amount, but it still cannot withstand the larger collapse and expansion forces. The third is also the idea of ​​the present invention. By designing the temperature measuring point or wire path of the thermocouple, the wire can have a certain flexibility, so that the wire has the function of releasing tension when it is stretched, and the stress release of the wire is achieved from the path process.

[0039] The thermocouple piece 2 with the slot-shaped notch 5 is an innovative design based on the traditional welded thermocouple piece. The main function of the traditional welded thermocouple piece is to form a small buffer platform on the platinum body to be monitored, and also serve as a welding platform for the thermocouple wire to avoid directly welding the thermocouple wire on the platinum body, which may affect the local quality of the platinum body. The thermocouple piece 2 with the slot-shaped notch of the present invention has a structure as shown in FIG. Figure 2 As shown, there is a groove-shaped notch feature 5 thereon, which can be made from a complete rectangular pair of pieces by cutting in the middle and bending locally, or by one-time stamping in a mass production process.

[0040] The characteristics of the formed notch meet the following requirements: the notch width is greater than 1.2 to 1.5 times the diameter of the thermocouple wire, and smaller than the diameter of the welding point of the thermocouple temperature measurement point, and the specific size of the diameter is in the range of 2.5 mm to 3.0 mm. The length of the notch is determined to be in the range of 20 mm to 50 mm according to the actual expansion and collapse. If it is too small, sufficient displacement release cannot be achieved. If it is too large, local deformation of the cooling pipe body 1 will cause the bending of the thermocouple sliding path, affecting the release of displacement. The same thermocouple monitoring points are also set in the adjacent area. Therefore, a reasonable range value is set in the design of the notch length.

[0041] like Figure 1 As shown, the notch is bent upward, so that a local cavity is formed between the inside of the notch and the cooling tube body 1. The cavity structure should be sufficient for the flexible movement of the thermocouple temperature measuring point welding point. During the actual heating process of the cooling tube body 1, the inclined tube body collapses and expands, causing the cooling tube body 1 to undergo an equivalent backward displacement at the thermocouple temperature measuring point. Therefore, during the initial setting, the thermocouple temperature measuring point should be placed at the front end of the slot-shaped notch to ensure sufficient displacement.

[0042] Considering that there is a filler material 7 outside the cooling tube body 1, and the material actually has a certain bonding property at 500°C, this has a fundamental impact on the implementation of the present invention. Therefore, it is necessary to add a protective layer on the thermocouple 2 to isolate the sintered filler material 7, such as Figure 3 As shown, a layer of ceramic fiber cloth 6 is laid on the outside of the thermocouple sheet 2. The material is insoluble at a high temperature of 1500°C, and the main component is Al2O3, with a content of ≥70% and a thickness of 0.5mm. Before laying, a gap of the same size as the groove-shaped notch 5 needs to be opened on the ceramic fiber cloth 6 to ensure that the internal couple wire can extend from the gap and has the ability to protect the movement of the temperature measuring point of the thermocouple sheet 2 and the thermocouple 4 below. The ceramic fiber cloth 6 has a larger area than the thermocouple sheet 2, and can ensure that the entire area of ​​the entire thermocouple sheet 2 is covered.

[0043] During the actual heating process, when the temperature of the cooling tube body 1 reaches above 600°C, local collapse and overall expansion displacement begin to occur. At this time, the internal slidable thermocouple temperature measuring point can produce matching displacement under the action of the tensile stress of the thermocouple wire. The principle is as follows: Figure 4 As shown, the thermocouple 4 will move along the groove-shaped notch 5 from a relatively lower end to the other end until the entire heating process is completed and the position of the thermocouple is finally fixed.

[0044] This method was applied to cooling tube bodies 1 of various sizes and achieved significant results. The failure rate of the top thermocouple during the heating stage was reduced by nearly 80%, effectively ensuring the process requirements of the temperature measurement capability in this area and providing reliable protection for the process control of large-flow glass.

[0045] The present invention proposes a device method for improving the reliability of the thermocouple in the channel cooling section during the heating stage. The thermocouple sheet 2 is installed on the cooling pipe body 1, and the thermocouple 4 is placed in the notch 5 on the thermocouple sheet 2. The notch 5 with a groove structure enables the thermocouple 4 to have a displacement release amount when the cooling section expands or collapses, thereby improving the reliability of the channel thermocouple.

[0046] Therefore, the structure proposed by the present invention has the following advantages: 1) The tension stress of the thermocouple wire is released by a small range of movement of the root of the thermocouple 4; 2) The surface of the root of the thermocouple 4 is covered with a protective ceramic fiber cloth 6 to keep the root of the thermocouple 4 movable and not affected by the sintering of the surrounding filler 7. 3) The metal sheet welded to the surface of the cooling tube body 1 is a thermocouple sheet 2, but it is different from the general form of thermocouple sheet, and it has an open groove-shaped notch 5. 4) At least one metal sheet is used to limit the temperature measurement point of the thermocouple 4. At least one temperature measurement point can be simultaneously in the form of multiple notches on one metal sheet or multiple metal sheets forming one notch.

[0047] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A device for improving the reliability of thermocouples in a channel cooling section during the heating stage, characterized in that: It comprises a thermocouple (4) and a thermocouple sheet (2) mounted on a cooling pipe body (1); A notch (5) with a slot-shaped structure is provided on the thermocouple sheet (2), a cavity is formed between the notch (5) and the cooling tube body (1), the root of the thermocouple (4) is arranged in the cavity, and the root of the thermocouple (4) is the temperature measurement point of the welded thermocouple.

2. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1 is characterized in that: A ceramic fiber cloth (6) is provided above the thermocouple piece (2).

3. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 2 is characterized in that: The surface area of ​​the ceramic fiber cloth (6) is greater than the surface area of ​​the thermocouple sheet (2).

4. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 2, characterized in that: A filling material (7) is provided above the ceramic fiber cloth (6).

5. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1 is characterized in that: The notch (5) is a rectangular gap, the gap width is greater than 1.2 to 1.5 times the diameter of the thermocouple (4), and the gap width is smaller than the diameter of the temperature measurement point.

6. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1, characterized in that: The length of the notch (5) ranges from 20 mm to 50 mm.

7. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1, characterized in that: There are a plurality of thermocouple pieces (2), and each thermocouple piece (2) is provided with a notch (5).

8. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1, characterized in that: A plurality of notches (5) are provided on the thermocouple piece (2).

9. The device for improving the reliability of thermocouples in the cooling section of the improvement channel during the heating stage according to claim 1, characterized in that: The thermocouple piece (2) is welded on the cooling tube body (1).

10. A method for improving the reliability of a thermocouple in a channel cooling section during a heating phase, characterized in that: The device for improving the reliability of the thermocouple in the cooling section of the channel during the heating stage according to any one of claims 1 to 9 comprises: The thermocouple sheet (2) is mounted on the cooling pipe body (1), and the thermocouple (4) is placed in the notch (5) at the notch (5) on the thermocouple sheet (2). The notch (5) has a groove structure so that the thermocouple (4) has a displacement release amount when the cooling section expands or collapses, thereby improving the reliability of the channel thermocouple.

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