Double thermocouple for measuring glass liquid temperature
By installing an vent pipe between the outer and inner sheaths of the double-layer thermocouple, the problem of outer sheath bursting was solved, thus improving the durability of the thermocouple and the accuracy of temperature measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 长利玻璃洪湖有限公司
- Filing Date
- 2025-06-26
- Publication Date
- 2026-06-23
AI Technical Summary
The outer tube of a double-layer thermocouple is prone to cracking during the preheating process of immersion in molten glass, which affects the quality of the glass.
An exhaust pipe is installed between the outer sleeve and the inner sleeve to discharge the expanding hot air inside the hot end cavity and prevent the outer sleeve from bursting.
It effectively prevents the outer sheath from bursting, avoids fragments contaminating the molten glass, extends the service life of the thermocouple, and ensures the accuracy of temperature measurement.
Smart Images
Figure CN224398829U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of thermocouple technology, specifically to a double-layer thermocouple for measuring the temperature of molten glass. Background Technology
[0002] Thermocouples are widely used in various temperature measurement fields, especially in float glass production lines. However, it has been found that thermocouples measuring the temperature of molten glass in the tin bath are partially immersed in the molten glass and are subject to constant erosion from the glass. This wear and tear on the outer corundum sheath is exacerbated by the glass's temperature exceeding 1300℃. Once the corundum sheath is corroded through, the inner thermocouple wire will be damaged by contact with the molten glass. Given the relatively high cost of S-type thermocouples, this results in significant losses. Therefore, the thermocouple sheath has been improved by using a double-layer design: an inner sheath inside the outer sheath, with the thermocouple wire installed inside the inner sheath. This effectively extends the thermocouple's service life.
[0003] However, a new problem has emerged during the use of double-layer thermocouples: the outer sheath is prone to bursting during the preheating process of molten glass, failing to achieve the desired effect. Furthermore, the bursting corundum sheath fragments can easily contaminate the molten glass, affecting glass quality. Therefore, there is an urgent need to provide a new thermocouple solution to address the problem of bursting during the preheating process of double-layer thermocouples. Utility Model Content
[0004] The purpose of this invention is to overcome the problem that the outer tube of a double-layer thermocouple is prone to bursting during the preheating process of molten glass. The invention provides a double-layer thermocouple for measuring the temperature of molten glass. The double-layer thermocouple includes an outer tube and an inner tube, and an exhaust pipe is provided in the cavity formed by the outer tube and the inner tube to prevent the outer tube from bursting.
[0005] To achieve the above objectives, this utility model provides a double-layer thermocouple for measuring the temperature of molten glass. The double-layer thermocouple includes an outer tube and an inner tube fitted inside the outer tube, forming a cavity between the outer tube and the inner tube. The double-layer thermocouple includes a hot end that contacts the molten glass and a cold end that is away from the molten glass. An exhaust pipe is arranged in the cavity near the cold end of the double-layer thermocouple. When the hot end of the double-layer thermocouple contacts the molten glass, the exhaust pipe is used to discharge the hot air that expands in the cavity of the hot end of the double-layer thermocouple.
[0006] Preferably, the temperature of the molten glass is ≥1300℃.
[0007] Preferably, the cavity near the cold end of the double thermocouple is filled with a high-temperature resistant fixing adhesive, which is used to fix the outer sleeve, the inner sleeve and the exhaust pipe.
[0008] Preferably, the number of exhaust pipes arranged in the cavity near the cold end of the double-layer thermocouple is 2 to 6.
[0009] Preferably, the length of the exhaust pipe is 25-50% of the length of the inner sleeve.
[0010] Preferably, the exhaust pipe is a two-hole conduit, wherein the outer diameter of the exhaust pipe is 0.8~1.2mm, the length of the exhaust pipe is 330~700mm, and the inner diameter of each hole in the two-hole conduit is 0.2~0.4mm.
[0011] Preferably, the cold end of the double-layer thermocouple is connected to the junction box, and the junction box has a wire hole; one end of the exhaust pipe is located in the cavity formed by the outer sleeve and the inner sleeve, and the other end is located in the junction box. The hot air that expands in the cavity of the hot end of the double-layer thermocouple is discharged through the exhaust pipe and discharged into the atmosphere through the wire hole in the junction box.
[0012] Preferably, the outer diameter of the outer sleeve is 20-30 mm, the thickness is 2-4 mm, and the length is 1300-1500 mm; preferably, the outer diameter of the inner sleeve is 8-12 mm, the thickness is 1-3 mm, and the length is 1300-1400 mm.
[0013] Preferably, an electrocoupler wire is installed inside the inner sleeve.
[0014] Compared with the prior art, the present invention has at least the following beneficial effects:
[0015] (1) The thermocouple described in this utility model is a double-layer thermocouple, that is, an inner tube is installed inside the outer tube, and a thermocouple wire is installed inside the inner tube. The outer tube protects the inner tube to prevent the inner tube from being worn and eroded when the thermocouple is inserted into the glass melt, and to avoid the thermocouple wire inside the inner tube from being damaged by sticking to the glass melt.
[0016] (2) By arranging an exhaust pipe in the cavity near the cold end of the thermocouple, when the hot end of the double-layer thermocouple comes into contact with the glass melt, the exhaust pipe can promptly discharge the hot air expanding in the cavity of the hot end of the double-layer thermocouple, thereby avoiding the expansion of gas volume that cannot be discharged, which would cause the outer tube to burst. This would prevent the fragments of the burst outer tube from contaminating the glass melt and affecting the glass quality. At the same time, it would prevent the inner tube from being worn, eroded, and penetrated by direct contact with the glass melt after the outer tube bursts, thus damaging the thermocouple wire. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the double-layer thermocouple for measuring the temperature of molten glass according to this utility model.
[0018] Figure 2This is a cross-sectional view of the double-layer thermocouple AA used for measuring the temperature of molten glass according to this utility model.
[0019] Figure 3 This is a schematic diagram of the wire hole of the junction box described in this utility model.
[0020] Explanation of reference numerals in the attached figures
[0021] 1 Outer tube; 2 Outer tube; 3 Cavity; 4 Cold end; 5 Hot end; 6 Exhaust pipe; 7 Fixing adhesive; 8 Junction box; 9 Wire hole. Detailed Implementation
[0022] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.
[0023] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0024] like Figure 1 and Figure 2 As shown, the double-layer thermocouple for measuring the temperature of molten glass provided by this utility model includes an outer tube 1 and an inner tube 2 sleeved inside the outer tube 1. A cavity 3 is formed between the outer tube 1 and the inner tube 2. The double-layer thermocouple includes a hot end 5 in contact with the molten glass and a cold end 4 away from the molten glass. An exhaust pipe 6 is arranged in the cavity 3 near the cold end 4 of the double-layer thermocouple. When the hot end 5 of the double-layer thermocouple is in contact with the molten glass, the exhaust pipe 6 is used to discharge the hot air that expands in the cavity 3 of the hot end 5 of the double-layer thermocouple.
[0025] In this invention, the temperature of the molten glass is relatively high. Generally, the temperature of the molten glass is ≥1300℃, preferably 1300~1600℃.
[0026] Furthermore, an electrocoupler wire (not shown in the figure) is installed inside the inner sleeve 2. The installation method of the electrocoupler wire can be a common method in the art, as long as it can achieve the purpose of this utility model. In a more specific embodiment, the electrocoupler wire can be installed on a double-hole electrocoupler fixing tube, the two electrocoupler wires are separated, and then the electrocoupler fixing tube is inserted into the inner sleeve 2.
[0027] The thermocouple described in this utility model is a double-layer thermocouple, that is, an inner tube 2 is installed inside the outer tube 1, and the thermocouple wire is installed inside the inner tube 2. Under the protection of the outer tube 1, the inner tube 2 does not come into direct contact with the glass melt when the thermocouple is inserted into the glass melt. Therefore, it can prevent the inner tube 2 from being worn, corroded and penetrated in the high temperature glass melt, and thus avoid the thermocouple wire inside the inner tube 2 from being damaged by sticking to the glass melt.
[0028] To ensure the concentricity of the outer sheath 1 and inner sheath 2 in a double-layer thermocouple, resulting in more uniform heating and more accurate temperature measurement, it is necessary to fix the outer sheath 1 and inner sheath 2. Simultaneously, this concentric fixation also prevents the inner sheath 2 from contacting the outer sheath 1 due to movement under external force, thus avoiding collision damage. In one embodiment, high-temperature resistant adhesive 7 can be filled into the cavity 3 near the cold end 4 of the double-layer thermocouple to fix the outer sheath 1 and inner sheath 2.
[0029] The most significant improvement of this invention lies in the arrangement of an exhaust pipe 6 within the cavity 3 near the cold end 4 of the thermocouple. When the hot end 5 of the double-layer thermocouple comes into contact with the molten glass, the air within the cavity 3 of the hot end 5 expands due to heat. The exhaust pipe 6 can promptly expel the expanded hot air from the cavity 3, preventing the outer sheath 1 from bursting due to the inability to expel the expanding gas. This, in turn, prevents fragments of the bursting outer sheath 1 from contaminating the molten glass and affecting its quality. Simultaneously, it prevents the inner sheath 2 from directly contacting the molten glass after the outer sheath 1 bursts, causing it to be worn, eroded, and penetrated, thus damaging the thermocouple wire. Especially after the cavity 3 near the cold end 4 of the double-layer thermocouple is filled with high-temperature resistant adhesive 7, the air within the cavity 3 of the hot end 5 expands more easily due to heat, making the outer sheath 1 more prone to bursting; therefore, it is even more necessary to expel the hot air.
[0030] In one implementation, such as Figure 1 As shown, the cold junction 4 of the double-layer thermocouple is connected to the junction box 8, as follows. Figure 3 As shown, the junction box 8 has a wire hole 9. One end (air inlet) of the exhaust pipe 6 is located inside the cavity 3 formed by the outer sleeve 1 and the inner sleeve 2, and the other end (air outlet) is located inside the junction box 8 and inserted into the wire hole 9. The hot air expanding inside the cavity 3 of the double-layer thermocouple hot junction 5 is discharged through the exhaust pipe 6 and into the atmosphere through the wire hole 9 in the junction box 8. The wire hole 9, in addition to its function of discharging air, also allows wires to pass through. The wires inside the thermocouple junction box 8 mainly serve as compensating wires.
[0031] After the exhaust pipe 6 is arranged in the cavity 3 formed by the outer sleeve 1 and the inner sleeve 2, it can also be fixed with adhesive 7. In a preferred embodiment, the cavity 3 near the cold end 4 of the double thermocouple is filled with high-temperature resistant adhesive 7. The adhesive 7 is used to fix the outer sleeve 1, the inner sleeve 2 and the exhaust pipe 6, thereby making the temperature measurement more accurate, avoiding the inner sleeve 2 from contacting the outer sleeve 1 due to shaking and causing collision damage, and at the same time allowing the expanded hot air to be discharged more stably, preventing the outer sleeve 1 from bursting.
[0032] In a preferred embodiment, the high-temperature resistant adhesive can meet the requirements for use in operating conditions above 1300°C, preferably 1300~1600°C. To achieve the aforementioned objective, for example, the high-temperature resistant adhesive can be a high-temperature adhesive made of aluminosilicates, inorganic ceramic powder, etc., that meets the requirements above 1300°C.
[0033] In this utility model, the outer sleeve 1, the inner sleeve 2, and the exhaust pipe 6 are all high-temperature resistant corundum tubes, which meet the requirements for use at high temperatures.
[0034] In one embodiment, the outer sleeve 1 has an outer diameter of 20-30 mm, a thickness of 2-4 mm, and a length of 1300-1500 mm. In another embodiment, the inner sleeve 2 has an outer diameter of 8-12 mm, a thickness of 1-3 mm, and a length of 1300-1400 mm. The length of the outer sleeve 1 is equal to the length of the inner sleeve 2, or the length of the outer sleeve 1 is greater than the length of the inner sleeve 2. In a preferred embodiment, the outer sleeve 1 has an outer diameter of 25 mm, a thickness of 3 mm, and a length of 1350 mm; the inner sleeve 2 has an outer diameter of 10 mm, a thickness of 2 mm, and a length of 1350 mm.
[0035] In some preferred embodiments, the length of the exhaust pipe 6 is 25-50% of the length of the inner sleeve 2 to ensure that the expanding hot air can be discharged in a timely manner. Specifically, when the length of the inner sleeve 2 is 1350 mm, the length of the exhaust pipe 6 is 500 mm.
[0036] In this invention, the length of the high-temperature resistant fixing adhesive 7 filling the cavity 3 is slightly shorter than the length of the exhaust pipe 6. Specifically, the length of the high-temperature resistant fixing adhesive 7 filling the cavity 3 can be 24-49% of the length of the inner sleeve 2. Since the outer sleeve 1 and the inner sleeve 2 are relatively long, if the length of the fixing adhesive 7 is too short, it will shake during transportation, causing the outer sleeve 1 and the inner sleeve 2 of the hot end 5 to collide with each other and easily break; if the length of the fixing adhesive 7 is too long, it will easily block the air inlet of the exhaust pipe 6, preventing the expanded hot air from being discharged.
[0037] To facilitate the rapid expulsion of the expanding hot air, multiple exhaust pipes 6 can be arranged within the cavity 3 near the cold end 4 of the double-layer thermocouple. In some embodiments, the number of exhaust pipes 6 arranged within the cavity 3 near the cold end 4 of the double-layer thermocouple is 2 to 6, preferably 4.
[0038] Furthermore, such as Figure 2 As shown, the exhaust pipe 6 is a two-hole conduit. The outer diameter of the exhaust pipe 6 can be 0.8~1.2mm, the length of the exhaust pipe 6 can be 330~700mm, and the inner diameter of each hole in the two-hole conduit can be 0.2~0.4mm. In a preferred embodiment, the outer diameter of the exhaust pipe 6 can be 1mm, the length of the exhaust pipe 6 can be 500mm, and the inner diameter of each hole in the two-hole conduit can be 0.3mm. In another embodiment, the exhaust pipe 6 can also be a single-hole conduit.
[0039] In a more specific implementation, such as Figures 1-3 As shown, a double-layer thermocouple for measuring the temperature of molten glass includes an outer tube 1 and an inner tube 2 fitted inside the outer tube 1. A thermocouple wire is installed inside the inner tube 2. A cavity 3 is formed between the outer tube 1 and the inner tube 2. The double-layer thermocouple includes a hot end 5 in contact with the molten glass at a temperature ≥1300℃ and a cold end 4 away from the molten glass. Two to six vent pipes 6 are arranged in the cavity 3 near the cold end 4. The cavity 3 near the cold end 4 is filled with high-temperature resistant adhesive 7, which is used to fix the outer tube 1, the inner tube 2, and the vent pipes 6. When the hot end 5 of the double-layer thermocouple contacts the molten glass, the vent pipes 6 discharge the expanding hot air from the cavity 3 containing the hot end 5. The cold end 4 of the double-layer thermocouple is connected to a junction box 8, which has a wire hole 9. One end of the vent pipe 6 is located on the outer tube 5. The hot air expanding inside the cavity 3 formed by the outer sleeve 1 and the inner sleeve 2 is located inside the junction box 8. The hot air is discharged through the exhaust pipe 6 and into the atmosphere through the wire hole 9 opened in the junction box 8. The length of the exhaust pipe 6 is 25-50% of the length of the inner sleeve 2. The exhaust pipe 6 is a double-hole conduit, wherein the outer diameter of the exhaust pipe 6 is 0.8-1.2 mm, the length of the exhaust pipe 6 is 330-700 mm, and the inner diameter of each hole in the double-hole conduit is 0.2-0.4 mm. The outer sleeve 1, the inner sleeve 2, and the exhaust pipe 6 are all high-temperature resistant corundum tubes. The outer sleeve 1 has an outer diameter of 20-30 mm, a thickness of 2-4 mm, and a length of 1300-1500 mm. The inner sleeve 2 has an outer diameter of 8-12 mm, a thickness of 1-3 mm, and a length of 1300-1400 mm.
[0040] This invention not only has the function of delaying wear with double-layer sleeves, but also plays the role of venting gas to prevent explosion, thereby preventing the molten glass from being contaminated by the explosion of the sleeves, and has significant economic benefits.
[0041] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.
[0042] Example
[0043] The double-layer thermocouple for measuring the temperature of molten glass provided by this utility model, such as Figures 1-3 As shown, it includes an outer tube 1 and an inner tube 2 sleeved inside the outer tube 1. A thermocouple wire is installed inside the inner tube 2. A cavity 3 is formed between the outer tube 1 and the inner tube 2. The double-layer thermocouple includes a hot end 5 that is in contact with the molten glass at a temperature ≥1300℃ and a cold end 4 that is away from the molten glass.
[0044] Four exhaust pipes 6 are arranged in the cavity 3 near the cold end 4 of the double thermocouple. The cavity 3 near the cold end 4 of the double thermocouple is filled with high-temperature resistant fixing adhesive 7. The fixing adhesive 7 is used to fix the outer tube 1, the inner tube 2 and the exhaust pipes 6. When the hot end 5 of the double thermocouple comes into contact with the molten glass, the exhaust pipes 6 are used to discharge the hot air that expands in the cavity 3 of the hot end 5 of the double thermocouple.
[0045] The cold junction 4 of the double-layer thermocouple is connected to the junction box 8. The junction box 8 has a wire hole 9. One end of the exhaust pipe 6 is located in the cavity 3 formed by the outer sleeve 1 and the inner sleeve 2, and the other end is located in the junction box 8. The hot air that expands in the cavity 3 of the hot junction 5 of the double-layer thermocouple is discharged through the exhaust pipe 6 and discharged into the atmosphere through the wire hole 9 in the junction box 8.
[0046] The length of the exhaust pipe 6 is 37% of the length of the inner sleeve 2. The exhaust pipe 6 is a double-hole conduit, wherein the outer diameter of the exhaust pipe 6 is 1 mm, the length of the exhaust pipe 6 is 500 mm, and the inner diameter of each hole in the double-hole conduit is 0.3 mm. The outer sleeve 1, the inner sleeve 2, and the exhaust pipe 6 are all high-temperature resistant corundum tubes. The outer sleeve 1 has an outer diameter of 25 mm, a thickness of 3 mm, and a length of 1350 mm. The inner sleeve 2 has an outer diameter of 10 mm, a thickness of 2 mm, and a length of 1350 mm.
[0047] This embodiment uses a double-layer thermocouple, that is, an inner tube is installed inside the outer tube, and thermocouple wires are installed inside the inner tube. The outer tube protects the inner tube, preventing the inner tube from being worn, corroded and penetrated when the thermocouple is inserted into the molten glass, and avoiding damage to the thermocouple wires inside the inner tube due to sticking to the molten glass.
[0048] In this embodiment, an exhaust pipe is arranged in the cavity near the cold end of the thermocouple. When the hot end of the double-layer thermocouple comes into contact with the molten glass, the exhaust pipe can promptly discharge the hot air expanding in the cavity of the hot end of the double-layer thermocouple. This avoids the outer tube from bursting due to the inability to expel the gas due to volume expansion, thereby preventing the fragments of the bursting outer tube from contaminating the molten glass and affecting the glass quality. At the same time, it prevents the inner tube from being worn, eroded, and penetrated by direct contact with the molten glass after the outer tube bursts, thus preventing damage to the thermocouple wire.
[0049] It should be understood that any parts not described in detail in this specification belong to the prior art.
[0050] The preferred embodiments of this utility model have been described in detail above; however, this utility model is not limited thereto. Within the scope of the technical concept of this utility model, various simple modifications can be made to the technical solution of this utility model, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed by this utility model and are all within the protection scope of this utility model.
Claims
1. A double-layer thermocouple for measuring the temperature of molten glass, characterized in that, The double thermocouple includes an outer tube (1) and an inner tube (2) fitted inside the outer tube (1). A cavity (3) is formed between the outer tube (1) and the inner tube (2). The double thermocouple includes a hot end (5) in contact with the molten glass and a cold end (4) away from the molten glass. An exhaust pipe (6) is arranged in the cavity (3) near the cold end (4) of the double thermocouple. When the hot end (5) of the double thermocouple is in contact with the molten glass, the exhaust pipe (6) is used to discharge the hot air that expands in the cavity (3) of the hot end (5) of the double thermocouple.
2. The double-layer thermocouple according to claim 1, characterized in that, The temperature of the molten glass is ≥1300℃.
3. The double-layer thermocouple according to claim 1 or 2, characterized in that, The cavity (3) near the cold end (4) of the double thermocouple is filled with a high-temperature resistant fixing adhesive (7), which is used to fix the outer sleeve (1), the inner sleeve (2) and the exhaust pipe (6).
4. The double-layer thermocouple according to claim 1, characterized in that, The number of exhaust pipes (6) arranged in the cavity (3) near the cold end (4) of the double-layer thermocouple is 2 to 6.
5. The double-layer thermocouple according to claim 1 or 4, characterized in that, The length of the exhaust pipe (6) is 25-50% of the length of the inner sleeve (2).
6. The double-layer thermocouple according to claim 1, characterized in that, The exhaust pipe (6) is a double-hole conduit, wherein the outer diameter of the exhaust pipe (6) is 0.8~1.2mm, the length of the exhaust pipe (6) is 330~700mm, and the inner diameter of each hole in the double-hole conduit is 0.2~0.4mm.
7. The double-layer thermocouple according to claim 1 or 6, characterized in that, The cold junction (4) of the double-layer thermocouple is connected to the junction box (8), and the junction box (8) has a wire hole (9). One end of the exhaust pipe (6) is located in the cavity (3) formed by the outer sleeve (1) and the inner sleeve (2), and the other end is located in the junction box (8). The hot air that expands in the cavity (3) of the double thermocouple hot end (5) is discharged through the exhaust pipe (6) and discharged into the atmosphere through the wire hole (9) opened in the junction box (8).
8. The double-layer thermocouple according to claim 1, characterized in that, The outer diameter of the outer sleeve (1) is 20~30mm, the thickness is 2~4mm, and the length is 1300~1500mm.
9. The double-layer thermocouple according to claim 1, characterized in that, The inner sleeve (2) has an outer diameter of 8~12mm, a thickness of 1~3mm, and a length of 1300~1400mm.
10. The double-layer thermocouple according to claim 1, characterized in that, The inner sleeve (2) is equipped with an electrocouple wire.