High-temperature and high-pressure thermocouple wire sealing structure

Abstract

The invention discloses a high-temperature and high-pressure thermocouple wire sealing structure, which comprises two thermocouple wires, one ends of the two thermocouple wires are welded to form a detection end, the high-temperature and high-pressure thermocouple wire sealing structure comprises a base, a graphite sealing element, a mounting joint and a pressing cap, the thermocouple wires are coated with a polytetrafluoroethylene sleeve, the polytetrafluoroethylene sleeve penetrates through the base and the graphite sealing element, and the graphite sealing element is arranged on the polytetrafluoroethylene sleeve. The base and the graphite sealing piece are wrapped by the installation connector, and the upper portion of the base is wrapped by the pressing cap. The thermocouple wire is simple and reasonable in structure, normal temperature measurement of the thermocouple wire can be ensured in an application scene where high temperature, high pressure and corrosion exist at the same time, and a measured medium cannot leak.

Description

Technical Field

[0001] The invention relates to the field of thermocouple wires, and in particular to a high-temperature and high-pressure thermocouple wire sealing structure. Background Art

[0002] The even-wire sealing structure will encounter application scenarios where high temperature, high pressure and corrosion exist simultaneously during use. Ordinary sealing structures on the market can usually only cope with one situation to ensure their sealing.

[0003] Therefore, there is an urgent need for a twin-wire sealing structure that can take into account a variety of operating environments. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a high-temperature and high-pressure twin-wire sealing structure that can cope with high temperature, high pressure and corrosion.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the present invention is: a high-temperature and high-pressure even-wire sealing structure, comprising two even-wires, one end of the two even-wires are welded to form a detection end, comprising a base, a graphite seal, a mounting joint, and a pressure cap, the even-wire is covered with a polyfluoro sleeve, the polyfluoro sleeve is passed through the base and the graphite seal, the mounting joint covers the base and the graphite seal, and the pressure cap covers the upper part of the base.

[0006] According to a preferred technical solution, the base is cylindrical, a through hole for the passage of the polytetrafluoroethylene sleeve is provided at the center of the base, and the upper end of the base is recessed to form a first receiving groove; the graphite seal is cylindrical, a through hole for the passage of the polytetrafluoroethylene sleeve is provided at the center of the graphite seal, the upper and lower ends of the graphite seal protrude to form a sealing platform, and the shape of the sealing platform at the lower end of the graphite seal matches the first receiving groove.

[0007] A further technical solution includes a pressure core and a pin. The pressure core is cylindrical. A through hole for the PTFE sleeve to pass through is arranged at the center of the pressure core. The lower end of the pressure core is concave to form a second receiving groove. Pin grooves are respectively opened on both sides of the upper part of the pressure core. The pin is installed in the pin grooves. The shape of the sealing platform at the lower end of the graphite seal matches the second receiving groove.

[0008] In the above technical solution, through the guidance of the pin, the pressing core can only move up and down but not rotate when being squeezed by the pressing cap, ensuring that the even wire passing through the middle will not be twisted off due to the rotation of the pressing core.

[0009] In the above technical solution, after the pressure cap is tightened, the graphite seal is squeezed, tightened and deformed by the pressure core and the base to form a sealing layer.

[0010] According to a further technical solution, a first external thread is fixedly provided on the upper portion of the mounting joint, and a second external thread is fixedly provided on the lower portion of the mounting joint; an internal thread is fixedly provided on the inner wall of the pressure cap, and the first external thread matches the internal thread.

[0011] According to a preferred technical solution, the pin is cylindrical, the pin groove is semicircular, and the pin matches the curvature of the pin groove.

[0012] According to a preferred technical solution, the sealing platform of the graphite seal has an isosceles trapezoidal cross-section in the vertical direction, and a bottom angle thereof is 30° to 60°.

[0013] In the above technical solution, the contact surfaces of the pressure cap, the base and the graphite seal are provided with chamfers and grooves at specific angles, and the squeeze seal can withstand higher pressure.

[0014] The advantages of the present invention are:

[0015] The present invention has a simple and reasonable structure and can ensure that the coupled wire can measure temperature normally and the measured medium will not leak in application scenarios where high temperature, high pressure and corrosion exist at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. The accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0018] Figure 1 It is a schematic diagram of the structure of the present invention;

[0019] Figure 2 It is an exploded view of the present invention;

[0020] Figure 3 It is a half-section diagram of the present invention;

[0021] Figure 4 A state diagram is used for this example.

[0022] Among them: 1. Even wire; 2. PTFE sleeve; 3. Installation joint; 4. Pressure cap; 5. Base; 6. Graphite seal; 7. Pressure core; 8. Pin. DETAILED DESCRIPTION

[0023] Example: Figure 1-3As shown, a high-temperature and high-pressure even-wire sealing structure includes two even-wires 1, one end of the two even-wires 1 is welded to form a detection end, including a base 5, a graphite seal 6, a mounting joint 3, and a pressure cap 4. The even-wire 1 is coated with a polyfluoro sleeve 2, the polyfluoro sleeve 2 passes through the base 5 and the graphite seal 6, the mounting joint 3 covers the base 5 and the graphite seal 6, and the pressure cap 4 covers the upper part of the base 5.

[0024] The base 5 is cylindrical, and a through hole for the polytetrafluoro sleeve 2 to pass through is set at the center of the base 5. The upper end of the base 5 is concave to form a first receiving groove; the graphite seal 6 is cylindrical, and a through hole for the polytetrafluoro sleeve 2 to pass through is set at the center of the graphite seal 6. The upper and lower ends of the graphite seal 6 protrude to form a sealing platform, and the shape of the sealing platform at the lower end of the graphite seal 6 matches the first receiving groove.

[0025] It includes a pressure core 7 and a pin 8. The pressure core 7 is cylindrical. A through hole for the PTFE sleeve 2 to pass through is set in the center of the pressure core 7. The lower end of the pressure core 7 is concave to form a second receiving groove. Pin grooves are respectively opened on both sides of the upper part of the pressure core 7. The pin 8 is installed in the pin groove. The shape of the sealing platform at the lower end of the graphite seal 6 matches the second receiving groove.

[0026] The upper part of the mounting joint 3 is fixedly provided with a first external thread, and the lower part of the mounting joint 3 is fixedly provided with a second external thread; the inner wall of the pressure cap 4 is fixedly provided with an internal thread, and the first external thread matches the internal thread.

[0027] The pin 8 is cylindrical, the pin groove is semicircular, and the curvature of the pin 8 matches that of the pin groove.

[0028] The cross-sectional shape of the sealing platform of the graphite sealing member 6 in the vertical direction is an isosceles trapezoid, and the bottom angle is 45°.

[0029] The method of using this embodiment is as follows:

[0030] Insert the PTFE sleeve 2 from the cold end of the even wire 1, and pass the cold end of the even wire 1 through the installation joint 3. Insert the base 5 and the graphite seal 6 into the cold end of the even wire 1 in sequence, push the base 5 and the graphite seal 6 into the installation joint 3 so that the bottom plane of the base 5 is flush with the installation joint 3. Weld the pin 8 to the two circular grooves on the surface of the pressure core 7, insert the pressure core 7 into the cold end of the even wire 1, align the two pins 8 on the pressure core 7 with the two circular grooves on the installation joint 3 and push it in, so that the pressure core 7 presses the graphite seal 6, screw the pressure cap 4 into the installation joint 3, so that the pressure cap 4 presses the pressure core 7, and tighten the pressure cap 4 with a torque wrench to apply a force of 80N.m.

[0031] like Figure 4As shown, after extrusion, the pressure core 7 is extruded downward by about 1.8 to 2 mm, and the graphite seal 6 is extruded and deformed. The deformed graphite seal 6 will completely fill the gap between the base 5, the pressure core 7 and the installation joint 3; the deformed graphite seal 6 will completely fill the gap between the polytetrafluoroethylene sleeve 2 and the base 5 and the pressure core 7. At the same time, the polytetrafluoroethylene sleeve 2 will be tightly attached to the even wire 1 after being extruded, thereby forming a sealing structure.

[0032] The even-wire sealing structure formed in this embodiment can withstand a pressure of 30 MPa at a room temperature of 20° C.; and can withstand a pressure of 6.5 MPa without leakage when the ambient temperature of the gasifier is about 200° C.

[0033] The applicable temperature is: long-term working temperature -73~260℃, extreme working temperature -200~280℃.

[0034] The even-wire sealing structure formed in this embodiment can withstand corrosion from acids such as concentrated nitric acid, concentrated sulfuric acid, concentrated hydrochloric acid, and hydrofluoric acid, corrosion from alkalis such as sodium hydroxide and potassium hydroxide, and corrosion from organic solvents such as acetone, toluene, ethanol, and methanol.

Claims

1. A high-temperature and high-pressure even-wire sealing structure, comprising two even-wires (1), one end of the two even-wires (1) being welded to form a detection end, characterized in that: The invention comprises a base (5), a graphite seal (6), a mounting joint (3), and a pressure cap (4); the even wire (1) is coated with a polytetrafluoroethylene sleeve (2); the polytetrafluoroethylene sleeve (2) passes through the base (5) and the graphite seal (6); the mounting joint (3) covers the base (5) and the graphite seal (6); and the pressure cap (4) covers the upper part of the base (5).

2. A high temperature and high pressure wire seal structure according to claim 1, characterized in that: The base (5) is cylindrical, and a through hole is provided at the center of the base (5) for the passage of the polytetrafluoroethylene sleeve (2), and the upper end of the base (5) is concave to form a first receiving groove; the graphite seal (6) is cylindrical, and a through hole is provided at the center of the graphite seal (6) for the passage of the polytetrafluoroethylene sleeve (2), and the upper and lower ends of the graphite seal (6) are protruding to form a sealing platform, and the shape of the sealing platform at the lower end of the graphite seal (6) matches the first receiving groove.

3. A high temperature and high pressure wire seal structure according to claim 2, characterized in that: The invention comprises a pressure core (7) and a pin (8). The pressure core (7) is cylindrical. A through hole for the polytetrafluoroethylene sleeve (2) to pass through is arranged at the center of the pressure core (7). The lower end of the pressure core (7) is concave to form a second receiving groove. Pin grooves are respectively arranged on both sides of the upper part of the pressure core (7). The pin (8) is installed in the pin groove. The shape of the sealing platform at the lower end of the graphite seal (6) matches the second receiving groove.

4. A high temperature and high pressure wire seal structure according to claim 3, characterized in that: The upper part of the mounting joint (3) is fixedly provided with a first external thread, and the lower part of the mounting joint (3) is fixedly provided with a second external thread; the inner wall of the pressure cap (4) is fixedly provided with an internal thread, and the first external thread matches the internal thread.

5. A high temperature and high pressure wire seal structure according to claim 3, characterized in that: The pin (8) is cylindrical, the pin groove is semicircular, and the pin (8) matches the curvature of the pin groove.

6. A high temperature and high pressure wire seal structure according to claim 2, characterized in that: The cross-sectional shape of the sealing platform of the graphite sealing member (6) in the vertical direction is an isosceles trapezoid, and the bottom angle is 30° to 60°.

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