A dual-function type high-temperature thermocouple

Abstract

The utility model discloses a dual functional type high temperature thermocouple, including parallelly arranged K type thermocouple and B type thermocouple, the K type thermocouple and B type thermocouple are passed through the upper protection tube, the fixed ring and the flange interface in order from top to bottom in common, and extend to corundum tube lining, the outside of corundum tube lining is equipped with the protective sleeve pipe, the utility model discloses a dual functional type high temperature thermocouple is composed of K type thermocouple and B type thermocouple, and the application range is wide, and the security is strong, and the operation is simple, and the measurement efficiency is high. Moreover, the high temperature thermocouple adopts the armored seal at the compression bolt, and is sealed through the installation winding type gasket and sleeve sealing at the movable bolt connection, and the electrical interface is two 1 / 2 'NPT (F) with the explosion -proof cable sealing joint, which greatly improves the sealing performance.

Description

Technical Field

[0001] This utility model relates to the field of thermocouple technology, and in particular to a dual-function high-temperature thermocouple. Background Technology

[0002] Thermocouples are commonly used temperature-sensing elements in temperature measuring instruments. They directly measure temperature and convert the temperature signal into a thermoelectric potential signal, which is then converted into the temperature of the measured medium by an electrical instrument (secondary instrument). The shapes of various thermocouples often differ greatly depending on the application, but their basic structure is roughly the same. They typically consist of thermocouples, insulating sheaths, protective tubes, and junction boxes, and are usually used in conjunction with display instruments, recording instruments, and electronic controllers. In certain special applications, such as chemical plants, smelters, power plants, and cement plants, ordinary thermocouples are easily damaged. Therefore, high-temperature thermocouples must be used in these situations.

[0003] High-temperature thermocouples mainly include types K, S, B, E, J, N, and T. Among them, type K thermocouples, also known as nickel-chromium / nickel-silicon thermocouples, are the most widely used type of base metal thermocouple. They have advantages such as good linearity, large thermoelectric potential, high sensitivity, good stability and uniformity, and strong oxidation resistance. They are suitable for oxidizing inert atmospheres, but not for reducing or alternating reduction-oxidation atmospheres at high temperatures or in a vacuum. Type S thermocouples are usually called single platinum-rhodium thermocouples. They belong to the precious metal thermocouple category, with a platinum-rhodium alloy as the positive electrode and platinum as the negative electrode. Their operating temperature is generally between 1200-1500℃. They have good physical and chemical stability and are typically used for high-temperature measurements requiring high accuracy. Type B thermocouples are usually called double platinum-rhodium thermocouples. They belong to the precious metal thermocouple category and have an operating temperature below 1800℃. They have advantages such as good stability and high accuracy.

[0004] However, the aforementioned high-temperature thermocouples are all single-function models with limited applicability, failing to meet the needs of use in complex environments. For example, in gasifiers in the coal chemical industry, temperature measurement typically begins with a type K preheating thermocouple used during the furnace baking process from room temperature to 800°C. Once the temperature reaches 800°C, a type B high-temperature thermocouple is then switched on to continue the high-temperature measurement process. This leads to numerous problems such as poor safety, cumbersome operation, and low measurement efficiency. Therefore, it is necessary in this field to design and develop a high-temperature thermocouple that can integrate multiple functional models. Utility Model Content

[0005] The purpose of this invention is to provide a dual-function high-temperature thermocouple.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] A dual-function high-temperature thermocouple includes a K-type thermocouple and a B-type thermocouple arranged side by side; the K-type thermocouple and the B-type thermocouple pass through an upper protective tube, a fixing ring and a flange interface from top to bottom, and extend into the inner lining of a corundum tube; a protective sleeve is fitted on the outer side of the inner lining of the corundum tube.

[0008] The upper outer side of the protective sleeve is fitted with a reinforcing tube, the upper part of which extends into the center hole of the flange and the outer wall of the reinforcing tube is welded to the flange.

[0009] The flange has a T-shaped central hole with an upper diameter larger than the lower diameter. The upper diameter of the flange's central hole is equal to the lower outer diameter of the flange interface, and the lower diameter of the flange's central hole is equal to the outer diameter of the reinforcing pipe. The lower part of the flange interface is embedded in the central hole of the flange, and the outer wall of the flange interface is welded to the flange.

[0010] The flange interface has a T-shaped cross-section for the central hole, with the upper diameter larger than the lower diameter. The retaining ring has an inverted T-shaped cross-section, with the lower outer diameter smaller than the upper diameter of the flange interface's central hole. The lower part of the retaining ring is placed in the central hole of the flange interface, and a spiral wound gasket is provided between the lower bottom surface of the retaining ring and the step of the central hole of the flange interface. A movable bolt is fitted on the outer side of the retaining ring, and the movable bolt is threaded to the upper sidewall of the central hole of the flange interface.

[0011] The bottom surface of the upper protective tube is provided with a groove; the top of the fixing ring extends into the groove of the upper protective tube and is welded together with the upper protective tube.

[0012] The upper protective tube has a T-shaped cross-section for its central hole, with the upper diameter being larger than the lower diameter. A sealing ring and a gasket are provided at the step of the central hole of the upper protective tube, and a clamping bolt is provided above the sealing ring and the gasket. The clamping bolt is threadedly connected to the inner wall of the central hole of the upper protective tube.

[0013] The upper part of the upper protective tube extends into the lower interface of the junction box, and the upper protective tube is fixed to the lower interface of the junction box by a nut.

[0014] The junction box is equipped with two electrical interfaces, which are 1 / 2" NPT(F) type and have explosion-proof cable sealing connectors.

[0015] The thermocouple wires of the K-type thermocouple and the B-type thermocouple are connected to the terminals inside the junction box and fixed with screws.

[0016] The portion between the bottom surface of the lower interface of the junction box and the bottom surface of the flange is an extension section, and the portion between the bottom surface of the flange and the bottom surface of the protective sleeve is an insertion section.

[0017] Compared with the prior art, the outstanding advantages of this utility model are:

[0018] This utility model's dual-function high-temperature thermocouple consists of a type K thermocouple and a type B thermocouple, offering wide applicability, strong safety, easy operation, and high measurement efficiency. Furthermore, the high-temperature thermocouple employs armored sealing at the clamping bolts and uses spiral wound gaskets and sleeves for sealing at the movable bolt connections. The electrical interface consists of two 1 / 2" NPT(F) explosion-proof cable sealing connectors, significantly improving sealing performance.

[0019] The dual-function high-temperature thermocouple of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a dual-function high-temperature thermocouple.

[0021] Among them, 1-Type K thermocouple, 2-Type B thermocouple, 3-Upper protective tube, 4-Fixing ring, 5-Flange interface, 6-Corundum tube liner, 7-Protective sleeve, 8-Reinforcing tube, 9-Modible bolt, 10-Spiral spiral wound gasket, 11-Flange, 12-Gateway box, 13-Pressure bolt, 14-Electrical interface. Detailed Implementation

[0022] like Figure 1 As shown, a dual-function high-temperature thermocouple includes a K-type thermocouple 1 and a B-type thermocouple 2 arranged side by side; the K-type thermocouple 1 and the B-type thermocouple 2 pass through the upper protective tube 3, the fixing ring 4 and the flange interface 5 from top to bottom, and extend into the corundum tube liner 6; a protective sleeve 7 is fitted on the outside of the corundum tube liner 6.

[0023] A reinforcing tube 8 is fitted on the upper outer side of the protective sleeve 7. The upper part of the reinforcing tube 8 extends into the center hole of the flange 11 and the outer wall of the reinforcing tube 8 is welded to the flange 11.

[0024] The central hole of flange 11 has a T-shaped cross-section, and the upper hole diameter is larger than the lower hole diameter; wherein, the upper hole diameter of the central hole of flange 11 is equal to the lower outer diameter of flange interface 5, and the lower hole diameter of the central hole of flange 11 is equal to the outer diameter of reinforcing tube 8; the lower part of flange interface 5 is embedded in the central hole of flange 11, and the outer wall of flange interface 5 is welded to flange 11.

[0025] The central hole of the flange interface 5 has a T-shaped cross-section, with the upper diameter larger than the lower diameter; the fixed ring 4 has an inverted T-shaped cross-section, with the lower outer diameter smaller than the upper diameter of the central hole of the flange interface 5; the lower part of the fixed ring 4 is placed in the central hole of the flange interface 5; a spiral wound gasket 10 is provided between the lower bottom surface of the fixed ring 4 and the step of the central hole of the flange interface 5; a movable bolt 9 is fitted on the outer side of the fixed ring 4, and the movable bolt 9 is threadedly connected to the upper sidewall of the central hole of the flange interface 5.

[0026] The bottom surface of the upper protective tube 3 is provided with a groove; the top of the fixing ring 4 extends into the groove of the upper protective tube 3 and is welded together with the upper protective tube 3.

[0027] The central hole of the upper protective tube 3 has a T-shaped cross-section, with the upper diameter larger than the lower diameter. A sealing ring and a gasket are provided at the step of the central hole of the upper protective tube 3. A clamping bolt 13 is located above the sealing ring and gasket, and the clamping bolt 13 is threaded to the inner wall of the central hole of the upper protective tube 3. After repeated testing, it was found that if the gasket's sealing point is placed on the flange edge or below the flange, the temperature is too high, making it less durable. However, when placed at the bottom of the junction box, the temperature is at room temperature, allowing the sealing point to be used for a long time without causing uneven installation due to frequent replacements.

[0028] The upper part of the upper protective tube 3 extends into the lower interface of the junction box 12, and the upper protective tube 3 is fixed together with the lower interface of the junction box 12 by a nut.

[0029] The junction box 12 is provided with two electrical interfaces 14, which are 1 / 2" NPT(F) type with explosion-proof cable sealing connectors. One of them is used to connect a type K thermocouple, and the other is used to connect a type B thermocouple.

[0030] The thermocouple wires of type K thermocouple 1 and type B thermocouple 2 are connected to the terminals inside junction box 12 and fixed with screws.

[0031] Junction box 12 is a 304SS stainless steel junction box.

[0032] The portion between the bottom surface of the lower interface of the junction box 12 and the bottom surface of the flange 11 is an extension section with a length of 200mm; the portion between the bottom surface of the flange 11 and the bottom surface of the protective sleeve 7 is an insertion section with a length of 900mm.

[0033] The K-type thermocouple is Class I, with an Inconel 600 sheath. The minimum diameter of the K-type thermocouple wire is φ0.9mm. The wire is insulated with heat shrink tubing. The reference end is sandblasted to a depth of about 10mm and filled with epoxy resin.

[0034] Type B thermocouples are fitted with PTFE insulating wires, use two-hole corundum insulating tubes, and have a glue-filled end cap filled with ES568 epoxy glue. The pressure test is 1.0 MPa.

[0035] The flange adopts ASME B16.5 150#2"RF, and the flange material is 316SS. The protective sleeve 7 uses imported C799 high-purity corundum pipe. The reinforcing pipe 8 is made of GH3039 alloy. The movable bolts are M40×1.5. The metal strip of the spiral wound gasket is made of 304 steel, and the filler material is flexible graphite tape.

[0036] The specific steps for manufacturing this dual-function high-temperature thermocouple are as follows:

[0037] (1) Insert the corundum tube liner into the inner hole of the protective sleeve; wherein, the corundum tube liner is wrapped with asbestos rope and glued to fix the protective sleeve and the corundum tube liner into shape.

[0038] (2) Insert the flange interface into the center hole of the flange;

[0039] (3) Insert the reinforcing tube into the center hole of the flange, and the top surface of the reinforcing tube is connected to the bottom surface of the flange interface to form a whole.

[0040] (4) Install a spiral wound gasket at the step of the center hole of the flange interface, then insert the retaining ring into the center hole of the flange interface, and fix the flange interface and the retaining ring together with the movable bolts.

[0041] (5) Fix the connection gap between the center hole of the flange and the reinforcing pipe after forming, and weld them together; connect and weld the upper protective pipe and the fixing ring together;

[0042] (6) Insert the fixed protective sleeve into the inner hole of the reinforcing tube, and then wrap asbestos rope around the outside of the protective sleeve to fix it into a whole.

[0043] (7) Pass the K-type thermocouple and the B-type thermocouple side by side from top to bottom through the upper protective tube, the fixing ring and the flange interface, and extend them into the inner lining of the corundum tube;

[0044] (8) The upper protective tube is fixed to the junction box end by a nut. A sealing ring and a gasket are provided at the step of the center hole of the upper protective tube. A clamping bolt is provided above the sealing ring and the gasket. The clamping bolt is connected to the upper protective tube 3 by a thread.

[0045] (9) Open the junction box cover, connect the wires inside the junction box to the terminals inside the junction box, and fix them with screws.

[0046] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A dual-function high-temperature thermocouple, characterized in that: It includes a K-type thermocouple (1) and a B-type thermocouple (2) arranged side by side; the K-type thermocouple (1) and the B-type thermocouple (2) pass through the upper protective tube (3), the fixing ring (4) and the flange interface (5) from top to bottom, and extend into the corundum tube liner (6); a protective sleeve (7) is provided on the outside of the corundum tube liner (6).

2. The dual-function high-temperature thermocouple according to claim 1, characterized in that: The upper outer side of the protective sleeve (7) is fitted with a reinforcing tube (8), the upper part of which extends into the center hole of the flange (11) and the outer wall of the reinforcing tube (8) is welded to the flange (11).

3. The dual-function high-temperature thermocouple according to claim 2, characterized in that: The central hole of the flange (11) has a T-shaped cross-section, and the upper hole diameter is larger than the lower hole diameter; wherein, the upper hole diameter of the central hole of the flange (11) is equal to the lower outer diameter of the flange interface (5), and the lower hole diameter of the central hole of the flange (11) is equal to the outer diameter of the reinforcing pipe (8); the lower part of the flange interface (5) is embedded in the central hole of the flange (11), and the outer wall of the flange interface (5) is welded to the flange (11).

4. The dual-function high-temperature thermocouple according to claim 3, characterized in that: The cross-section of the central hole of the flange interface (5) is T-shaped, and the upper hole diameter is larger than the lower hole diameter; the cross-section of the fixing ring (4) is inverted T-shaped, and the lower outer diameter of the fixing ring (4) is smaller than the upper hole diameter of the central hole of the flange interface (5); the lower part of the fixing ring (4) is placed in the central hole of the flange interface (5); a spiral wound gasket (10) is provided between the lower bottom surface of the fixing ring (4) and the step of the central hole of the flange interface (5); a movable bolt (9) is sleeved on the outside of the fixing ring (4); the movable bolt (9) is connected to the upper side wall of the central hole of the flange interface (5) by threads.

5. The dual-function high-temperature thermocouple according to claim 4, characterized in that: The bottom surface of the upper protective tube (3) is provided with a groove; the top of the fixing ring (4) extends into the groove of the upper protective tube (3) and is welded together with the upper protective tube (3).

6. The dual-function high-temperature thermocouple according to claim 5, characterized in that: The central hole of the upper protective tube (3) has a T-shaped cross-section, and the upper hole diameter is larger than the lower hole diameter; a sealing ring and a gasket are provided at the step of the central hole of the upper protective tube (3), and a clamping bolt (13) is provided above the sealing ring and the gasket. The clamping bolt (13) is connected to the inner wall of the central hole of the upper protective tube (3) by threads.

7. The dual-function high-temperature thermocouple according to claim 6, characterized in that: The upper part of the upper protective tube (3) extends into the lower interface of the junction box (12), and the upper protective tube (3) is fixed together with the lower interface of the junction box (12) by a nut.

8. The dual-function high-temperature thermocouple according to claim 7, characterized in that: The junction box (12) is provided with two electrical interfaces (14), which are 1 / 2" NPT(F) type and have explosion-proof cable sealing joints.

9. The dual-function high-temperature thermocouple according to claim 8, characterized in that: The wires of the K-type thermocouple (1) and the B-type thermocouple (2) are connected to the terminals inside the junction box (12) and fixed with screws.

10. The dual-function high-temperature thermocouple according to claim 9, characterized in that: The portion between the bottom surface of the lower interface of the junction box (12) and the bottom surface of the flange (11) is an extension section, and the portion between the bottom surface of the flange (11) and the bottom surface of the protective sleeve (7) is an insertion section.

Images