Armoured tungsten-rhenium thermocouple

Abstract

The utility model provides a kind of armoured tungsten-rhenium thermocouple, belong to temperature measurement technical field, this armoured tungsten-rhenium thermocouple, including armoured protection pipe, the tungsten-rhenium electrode being arranged in armoured protection pipe inside, insulation material being filled between armoured protection pipe and tungsten-rhenium electrode, terminal box and sealing assembly being arranged in armoured protection pipe one end, pass through double sealing structure, construct full-closed protection system, can effectively resist the invasion of high-temperature molten gas in metallurgical furnace, strong corrosive medium in chemical reaction kettle, make tungsten-rhenium electrode and alumina ceramic insulation layer exempt from corrosion, compared with traditional thermocouple service life improves 2-3 times.Simultaneously, spring-like elastic support piece and ceramic powder insulation layer form double anti-vibration structure.

Description

Technical Field

[0001] This utility model belongs to the field of temperature measurement technology, specifically relating to an armored tungsten-rhenium thermocouple. Background Technology

[0002] Tungsten-rhenium thermocouples are high-temperature resistant thermocouples, mainly of three types, with the highest operating temperature exceeding 2000℃. Tungsten-rhenium thermocouples have advantages such as high melting point, high sensitivity, good temperature-potential linear relationship, high thermal stability, and low price. They can partially replace platinum-rhodium thermocouples as ultra-high temperature measurement tools in high-tech metallurgical industries, high-temperature electronic thermoelectric system structural engineering, space vehicles, and nuclear reactors.

[0003] The patent application number "CN217878065U" describes an armored tungsten-rhenium thermocouple, comprising a tungsten-rhenium thermocouple wire, an armored protective tube, and a high-purity insulating column. The tungsten-rhenium thermocouple wire is inserted into the high-purity insulating column, which is entirely inserted into the armored protective tube. The armored protective tube is either vacuum-sealed or filled with inert gas, and the armored protective tube is then welded to a cap. Compared with traditional precious metal thermocouples, it has advantages such as measuring higher temperatures and lower price; compared with traditional assembled tungsten-rhenium thermocouples, it has advantages such as wider applicability and longer service life.

[0004] Compared with traditional precious metal thermocouples, the above-mentioned patents have advantages such as measuring higher temperatures and lower prices; compared with traditional assembled tungsten-rhenium thermocouples, they have advantages such as wider applicability and longer service life. However, the above-mentioned patents have certain limitations in use. Traditional armored tungsten-rhenium thermocouples have insufficient sealing performance, poor vibration resistance, and hysteretic thermal response under high temperature, high pressure, strong corrosion, and vibration environments. Utility Model Content

[0005] The purpose of this invention is to provide an armored tungsten-rhenium thermocouple, which aims to solve the problems of insufficient sealing performance, poor vibration resistance, and sluggish thermal response of traditional armored tungsten-rhenium thermocouples in the prior art under high temperature, high pressure, strong corrosion and vibration environments.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] An armored tungsten-rhenium thermocouple includes an armored protective tube, a tungsten-rhenium electrode disposed inside the armored protective tube, an insulating material filled between the armored protective tube and the tungsten-rhenium electrode, a junction box disposed at one end of the armored protective tube, and a sealing assembly.

[0008] The armored protective tube is also equipped with elastic support components to improve vibration resistance.

[0009] As a preferred embodiment of this utility model, the armored protective tube is made of a high-temperature resistant and corrosion-resistant nickel-based alloy material, and the tube wall thickness is optimized to reduce thermal resistance.

[0010] As a preferred embodiment of this utility model, the tungsten-rhenium electrode is composed of two high-purity tungsten-rhenium alloy wires of different compositions. The two alloy wires are insulated from each other and arranged in parallel inside the armored protective tube, with their ends extending to both ends of the armored protective tube.

[0011] In a preferred embodiment of this invention, the insulating material is alumina ceramic powder, which is uniformly filled between the armored protective tube and the tungsten-rhenium electrode through a filling process to form a tight insulating layer.

[0012] In a preferred embodiment of this utility model, the junction box is located at the non-measuring end of the armored protective tube, and has wiring terminals inside. The outer shell of the junction box is connected to the armored protective tube by threads, and a sealing ring is provided at the connection.

[0013] As a preferred embodiment of this utility model, the sealing assembly includes a sealing cap disposed at the measuring end of the armored protective tube and a high-temperature resistant sealant filled between the sealing cap and the armored protective tube. The sealing cap is made of an alloy material of the same material as the armored protective tube and is connected to the measuring end of the armored protective tube by threads.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] 1. This solution utilizes a double-sealed structure to construct a fully enclosed protective system, effectively resisting the intrusion of high-temperature molten gases in metallurgical furnaces and highly corrosive media in chemical reactors. This protects the tungsten-rhenium electrodes and alumina ceramic insulation layer from corrosion, extending their service life by 2-3 times compared to traditional thermocouples. Simultaneously, the spring-like elastic support and ceramic powder insulation layer form a dual vibration-resistant structure. Through elastic buffering and rigid fixation, electrode vibration displacement is suppressed. In simulated industrial vibration tests, after 100 hours of continuous vibration, the measurement error remains within ±1℃. This solves the problems of electrode breakage and insulation failure caused by vibration in traditional structures, significantly improving measurement stability under complex operating conditions.

[0016] 2. In this solution, a thin-walled, high thermal conductivity nickel-based alloy armored protective tube is used, combined with a vacuum-dense filling process of a high-purity alumina ceramic insulation layer. This significantly reduces thermal resistance and shortens the thermal response time from the traditional 20 seconds to less than 12 seconds. It can capture signals from rapid temperature change scenarios such as quenching and melting in real time. Two parallel insulated high-purity tungsten-rhenium electrodes extend directly to the measurement end, reducing intermediate conduction links. With the optimized heat conduction path, it ensures rapid and stable output of thermoelectric potential signals, meeting the stringent requirements of modern industrial automation control for real-time temperature measurement and accuracy. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a perspective view of the present utility model;

[0019] Figure 2 This is a first-person exploded perspective view of the present invention.

[0020] In the diagram: 1. Armored protective tube; 2. Insulating material; 3. Tungsten-rhenium electrode; 4. Elastic support component. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Example 1

[0023] Please see Figures 1-2 The present invention provides the following technical solution:

[0024] An armored tungsten-rhenium thermocouple includes an armored protective tube 1, a tungsten-rhenium electrode 3 disposed inside the armored protective tube 1, an insulating material 2 filled between the armored protective tube 1 and the tungsten-rhenium electrode 3, a junction box disposed at one end of the armored protective tube 1, and an elastic support member 4.

[0025] The armored protective tube 1 is also equipped with an elastic support 4 to improve vibration resistance.

[0026] In a specific embodiment of this utility model, the armored protective tube 1 is made of a high-temperature resistant and corrosion-resistant nickel-based alloy material. As the integral armored protective tube 1 of the thermocouple, its function is to provide a physical protective barrier for the internal tungsten-rhenium electrode 3 and insulating material 2. In high-temperature, high-pressure, and highly corrosive industrial environments, such as metallurgical furnaces and chemical reaction vessels, it can resist the erosion of external high-temperature and corrosive media, ensuring the integrity of the internal structure of the thermocouple.

[0027] The tungsten-rhenium electrode 3 consists of two high-purity tungsten-rhenium alloy wires of different compositions. As the core component for temperature sensing 3, it is the core component for temperature measurement. According to the Seebeck effect, when the thermocouple measuring end comes into contact with the object being measured, a thermoelectric potential is generated across the two tungsten-rhenium electrodes due to the temperature difference. The magnitude of this thermoelectric potential is proportional to the temperature difference. By transmitting the generated thermoelectric potential to an external temperature measuring instrument, the temperature of the object being measured can be measured.

[0028] The insulating material 2 is made of alumina ceramic powder. As an electrical isolation insulating material 2, it is uniformly filled between the armored protective tube 1 and the tungsten rhenium electrode 3 through a filling process to form a tight insulating layer. Its main function is to isolate the tungsten rhenium electrode 3 from the armored protective tube 1, as well as the electrical connection between the two tungsten rhenium electrodes 3, to prevent short circuits.

[0029] The junction box is located at the non-measuring end of the armored protective tube 1 and serves as a signal transmission connection component. It has internal terminals for connecting the tungsten rhenium electrode 3 to an external temperature measuring instrument to achieve thermoelectric potential transmission. The junction box shell is connected to the armored protective tube 1 by threads.

[0030] The elastic support 4 includes a sealing cap disposed at the measuring end of the armored protective tube 1 and high-temperature resistant sealant filled between the sealing cap and the armored protective tube 1, serving as the elastic support 4 for the measuring end. The sealing cap is made of the same alloy material as the armored protective tube 1 and is connected to the measuring end of the armored protective tube 1 by threads. Together with the high-temperature resistant sealant, it forms a double sealing structure, which can effectively prevent external corrosive media from entering the thermocouple from the measuring end, protect the tungsten rhenium electrode 3 and the insulating material 2 from corrosion, extend the service life of the thermocouple, and improve its stability in harsh environments.

[0031] The elastic support 4 is a high-temperature resistant spring-like structure, serving as an anti-vibration elastic support for the electrode. It is sleeved on the tungsten-rhenium electrode 3, with both ends fixedly connected to the inner wall of the armored protective tube 1 and the tungsten-rhenium electrode 3, respectively. When industrial equipment vibrates during operation, it can buffer the impact of vibration on the tungsten-rhenium electrode 3, preventing displacement, deformation, or even breakage of the electrode. This ensures the positional stability of the electrode under vibration, thereby maintaining the accuracy and stability of thermocouple measurements and reducing measurement errors and the probability of malfunctions caused by vibration.

[0032] Please refer to the details. Figures 1-2 The armored protective tube 1 is made of high-temperature and corrosion-resistant nickel-based alloy material, and the tube wall thickness has been optimized to reduce thermal resistance.

[0033] In this embodiment: the optimized tube wall thickness allows heat to be transferred to the tungsten-rhenium electrode 3 more quickly, while providing a stable support environment for the internal components; when connected to the junction box, its external thread structure is adapted to the internal thread of the junction box shell, and a sealing ring is used to achieve a seal; the measuring end and the sealing cap are screwed together by threads, and with the addition of high-temperature resistant sealant, a complete protection system is formed, which effectively resists the influence of the external environment on the internal structure.

[0034] Please refer to the details. Figures 1-2 The tungsten-rhenium electrode 3 is composed of two high-purity tungsten-rhenium alloy wires of different compositions. The two alloy wires are insulated from each other and are arranged in parallel inside the armored protective tube 1, with their ends extending to both ends of the armored protective tube 1.

[0035] In this embodiment: two mutually insulated tungsten-rhenium alloy wires are kept in a stable position inside the armored protective tube 1. One end is connected to an external temperature measuring instrument through a terminal block in the junction box to realize the transmission of thermoelectric potential; the other end is exposed to the measuring end and generates thermoelectric potential by contacting the object being measured.

[0036] Please refer to the details. Figure 2 The insulating material 2 is alumina ceramic powder, which is uniformly filled between the armored protective tube 1 and the tungsten rhenium electrode 3 through a filling process to form a tight insulating layer.

[0037] In this embodiment, alumina ceramic powder is filled in the gap between the armored protective tube 1 and the tungsten-rhenium electrode 3. On the one hand, it isolates the two tungsten-rhenium electrodes 3 to prevent short circuits and ensure the accurate generation of thermoelectric potential signals. On the other hand, together with the armored protective tube 1, it fixes the tungsten-rhenium electrode 3 and restricts the movement of the electrodes.

[0038] Please refer to the details. Figures 1-2 The junction box is located at the non-measuring end of the armored protective tube 1, and has wiring terminals inside. The junction box shell is connected to the armored protective tube 1 by threads, and a sealing ring is provided at the connection.

[0039] In this embodiment: the junction box is tightly connected to the armored protective tube 1 via threads, and a sealing ring fills the thread gaps to prevent external corrosive substances from entering. The internal terminals precisely connect the tungsten-rhenium electrode 3 to the external temperature measuring instrument, enabling signal transmission. Its sealing structure corresponds to the elastic support 4 at the measuring end of the armored protective tube 1, providing protection for the internal structure of the thermocouple from both ends, ensuring that the thermoelectric potential generated by the internal electrodes can be stably and accurately transmitted to the measuring instrument in harsh environments, without being interfered with by external factors.

[0040] Please refer to the details. Figures 1-2The sealing assembly includes a sealing cap disposed at the measuring end of the armored protective tube 1 and a high-temperature resistant sealant filled between the sealing cap and the armored protective tube 1. The sealing cap is made of the same alloy material as the armored protective tube 1 and is connected to the measuring end of the armored protective tube 1 by threads.

[0041] In this embodiment, the sealing cap and the measuring end of the armored protective tube 1 are screwed together, and high-temperature resistant sealant fills the gap between them, forming a double seal. This sealing assembly cooperates with the sealing structure of the junction box to completely seal the internal space of the armored protective tube 1, preventing corrosive gases and liquids from entering from both ends. At the same time, the sealing cap provides additional protection for the tungsten-rhenium electrode 3 at the measuring end, ensuring that the electrode is not corroded by the external environment when it is in contact with the object being measured to measure temperature, thus maintaining the stability of the thermocouple's performance and service life.

[0042] The working principle and usage process of this utility model: Traditional armored tungsten-rhenium thermocouples suffer from insufficient sealing, poor vibration resistance, and delayed thermal response under high temperature, high pressure, strong corrosion, and vibration environments. The following operational process achieves a systematic improvement: Regarding improved sealing performance, a nickel-based alloy sealing cap of the same material as the armored protective tube 1 is screwed into the measuring end of the armored protective tube 1 via threads. High-temperature resistant sealant is filled into the thread gap, forming a double-sealing structure composed of the sealing cap and the high-temperature resistant sealant. Simultaneously, the junction box shell is connected to the armored protective tube 1 via threads, with a sealing ring embedded at the connection point to prevent corrosive media from entering from the connection between the junction box and the armored protective tube 1. Regarding optimized vibration resistance, a spring-shaped elastic support 4 is sleeved on the outside of the tungsten-rhenium electrode 3, with its two ends fixed to the inner wall of the armored protective tube 1 and the tungsten-rhenium electrode 3, respectively. Simultaneously, a filling process is used to... Alumina ceramic powder insulating material 2 is uniformly filled into the gap between the armored protective tube 1 and the tungsten rhenium electrode 3, forming a tight insulating layer. The elastic support 4 and the insulating material 2 together constitute a double anti-vibration structure. In terms of improving thermal response performance, the thin-walled high thermal conductivity nickel-based alloy armored protective tube 1 is used. When the whole system works together, the measuring end of the tungsten rhenium electrode 3 contacts the object being measured. The high temperature is quickly conducted to the tungsten rhenium electrode 3 through the armored protective tube 1 and the insulating material 2 to generate a thermoelectric potential. The thermoelectric potential is transmitted to the external instrument through the wiring terminals in the junction box. During this process, the double sealing structure formed by the sealing cap of the measuring end and the high temperature resistant sealant, the threaded connection of the junction box and the sealing ring isolates the corrosive medium throughout the process. The elastic support 4 and the insulating material 2 suppress the interference of vibration on the tungsten rhenium electrode 3. The optimized armored protective tube 1 and the insulating material 2 shorten the thermal response time, enabling the thermocouple to work stably in harsh environments.

[0043] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A sheathed tungsten-rhenium thermocouple, characterized in that: It includes an armored protective tube (1), a tungsten-rhenium electrode (3) disposed inside the armored protective tube (1), an insulating material (2) filling the space between the armored protective tube (1) and the tungsten-rhenium electrode (3), a junction box disposed at one end of the armored protective tube (1), and a sealing assembly; The armored protective tube (1) is also equipped with an elastic support (4) to improve vibration resistance.

2. The armored tungsten-rhenium thermocouple according to claim 1, characterized in that: The armored protective tube (1) is made of high-temperature and corrosion-resistant nickel-based alloy material, and the tube wall thickness is optimized to reduce thermal resistance.

3. The armored tungsten-rhenium thermocouple according to claim 1, characterized in that: The tungsten-rhenium electrode (3) is composed of two high-purity tungsten-rhenium alloy wires of different compositions. The two alloy wires are insulated from each other and are arranged in parallel inside the armored protective tube (1), with their ends extending to the two ends of the armored protective tube (1).

4. The armored tungsten-rhenium thermocouple according to claim 1, characterized in that: The insulating material (2) is alumina ceramic powder, which is uniformly filled between the armored protective tube (1) and the tungsten rhenium electrode (3) through a filling process to form a tight insulating layer.

5. The armored tungsten-rhenium thermocouple according to claim 1, characterized in that: The junction box is located at the non-measuring end of the armored protective tube (1), and has wiring terminals inside. The outer shell of the junction box is connected to the armored protective tube (1) by threads, and a sealing ring is provided at the connection.

6. The armored tungsten-rhenium thermocouple according to claim 1, characterized in that: The sealing assembly includes a sealing cap disposed at the measuring end of the armored protective tube (1) and a high-temperature resistant sealant filled between the sealing cap and the armored protective tube (1). The sealing cap is made of the same alloy material as the armored protective tube (1) and is connected to the measuring end of the armored protective tube (1) by threads.

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