High-temperature and high-pressure radio frequency admittance level meter probe

Abstract

The invention relates to the technical field of material level detection, in particular to a high-temperature and high-pressure radio frequency admittance level meter probe, and aims to overcome the defects caused by high temperature of a detection conductor in an existing radio frequency admittance level meter probe. In order to achieve the purpose, the radio frequency admittance level meter probe comprises a shell, an insulating and heat-insulating sleeve and a detection conductor, the insulating and heat-insulating sleeve is contained in the shell, the tail end of the insulating and heat-insulating sleeve extends out of the shell, and the insulating and heat-insulating sleeve is hollow and the tail end of the insulating and heat-insulating sleeve is closed; the detection conductor comprises a spring, and the tail end of the spring abuts against the insulation heat insulation sleeve. After the temperature of the detection conductor is changed, the spring can contract or extend, the same length is kept all the time, and the measurement accuracy of the probe of the radio frequency admittance level meter is not affected. In addition, the elongation and shrinkage of the spring caused by temperature change can be converted into elastic potential energy, and the acting force applied to the insulating and heat-insulating sleeve by the spring is not changed greatly, so that the insulating and heat-insulating sleeve is not damaged.

Description

Technical Field

[0001] The invention relates to the technical field of level detection, and specifically provides a high-temperature and high-pressure radio frequency admittance level meter probe. Background Art

[0002] There are many types of existing level meter probes, such as capacitive level meter probes and radio frequency admittance level meter probes. Capacitive level meter probes include a detection conductor. As the material level rises, the material covers the detection conductor, and the capacitance value between the detection conductor and the medium in the circuit (in the case of conductive materials) or the capacitance value between the detection conductor and the pipe wall (in the case of insulating materials) increases accordingly. Since the change in the material level causes the imbalance of the capacitance bridge, the change in the capacitance value depends on the dielectric constant of the material being measured, and then the signal is detected and amplified, and finally the corresponding signal is output.

[0003] The measurement principle of the RF admittance level meter probe is similar to that of the capacitive level meter probe. The detection conductor and the container wall form a two-stage capacitor with a fixed spacing. After the material level in the container covers the detection conductor, the medium and the air above the medium act as the filling between the capacitors. The RF admittance level meter probe can emit a certain high-frequency radio wave to act on the detection conductor. As the level of the medium changes, the electrical parameters (such as capacitance and admittance) between the detection conductor and the container wall change, which in turn causes the change of the radio wave acting on the detection conductor. According to the change of the radio wave, the level of the medium can be analyzed and calculated. The measurement results of the RF admittance level meter probe are highly accurate and are not affected by the hanging material on the detection conductor.

[0004] In order to expand the measuring range of the RF admittance level meter probe, the length of the detection conductor can reach four meters. As the temperature of the detection conductor changes, the length of the detection conductor in the conventional RF admittance level meter probe will change slightly (such as thermal expansion or thermal contraction). Once the length of the detection conductor changes, it will affect the measurement accuracy of the RF admittance level meter probe. In addition, since the initial end of the detection conductor is fixed, once the length of the detection conductor becomes longer, it will exert a greater force on the insulating and heat-insulating sleeve installed on the outer periphery of the detection conductor, and there is a risk of damaging the insulating and heat-insulating sleeve.

[0005] Therefore, there is an urgent need for a high-temperature and high-pressure radio frequency admittance level meter probe to solve the drawbacks of the detection conductor in the existing radio frequency admittance level meter probe caused by high temperature. Summary of the invention

[0006] The present invention aims to solve the above technical problem, that is, to solve the drawbacks of the detection conductor in the existing radio frequency admittance level meter probe caused by high temperature.

[0007] In a first aspect, the present invention provides a high-temperature and high-pressure radio frequency admittance level meter probe, comprising: a shell having a cavity extending through the shell along an axis; an insulating and heat-insulating sleeve accommodated in the cavity and with its end extending out of the shell, the insulating and heat-insulating sleeve being hollow and with its end closed; a detection conductor comprising a spring, the spring being inserted into the insulating and heat-insulating sleeve and with its end abutting against the insulating and heat-insulating sleeve.

[0008] By adopting the above technical solution, after the temperature of the detected conductor changes, the spring can shrink or stretch, always maintaining the same length, and will not affect the measurement accuracy of the RF admittance level meter probe; in addition, the elongation and contraction of the spring caused by temperature changes can be converted into elastic potential energy, and the force applied by the spring to the insulating and heat-insulating sleeve does not change much, and will not damage the insulating and heat-insulating sleeve.

[0009] In a specific embodiment of the high temperature and high pressure radio frequency admittance level meter probe, the detection conductor further comprises a hard portion, which is connected to an end of the spring away from the insulating and heat-insulating sleeve and fixed to the shell.

[0010] In the specific implementation of the high temperature and high pressure radio frequency admittance level meter probe described above, the top of the cavity is a receiving groove, and the initial end of the insulating thermal insulation sleeve is located in the receiving groove; the high temperature and high pressure radio frequency admittance level meter probe also includes a pressing piece and a thermal insulation sealing pad, the thermal insulation sealing pad is located in the receiving groove and is sleeved on the initial end of the insulating thermal insulation sleeve, at least a portion of the pressing piece is located in the receiving groove and is connected to the shell to force the thermal insulation sealing pad to abut against the bottom of the receiving groove.

[0011] By adopting the above technical solution, the pressing piece can press the thermal insulation sealing pad tightly, thereby sealing the gap between the insulating thermal insulation sleeve and the shell, preventing hot air from transferring heat upward from the gap between the insulating thermal insulation sleeve and the shell; at the same time, it can also improve the pressure resistance of the RF admittance level meter probe.

[0012] In the specific implementation of the above-mentioned high-temperature and high-pressure radio frequency admittance level meter probe, the high-temperature and high-pressure radio frequency admittance level meter probe also includes an insulating block and a locking piece, the insulating block and the locking piece are inserted into the pressing piece, the insulating block is located between the locking piece and the pressing piece, and the initial end of the detection conductor is fixed to the locking piece.

[0013] By adopting the above technical solution, the insulating block can insulate the locking part and the pressing part to prevent the detection conductor from being electrically connected to the shell through the locking part and the pressing part; in addition, the insulating block can also reduce the heat conduction efficiency between the locking part and the pressing part, thereby reducing the temperature of the detection conductor, and then improving the maximum heat resistance temperature of the radio frequency admittance level switch.

[0014] In the above-mentioned specific implementation of the high-temperature and high-pressure radio frequency admittance level meter probe, a heat sink is provided on the outer periphery of the shell.

[0015] By adopting the above technical solution, the heat sink can accelerate the heat dissipation speed of the shell, thereby reducing the temperature of the shell to increase the ultimate tolerance temperature of the radio frequency admittance level switch.

[0016] In the above-mentioned specific implementation of the high temperature and high pressure radio frequency admittance level meter probe, an isolator is arranged in the cavity, and the isolator is sleeved outside the insulating and heat-insulating sleeve and is configured to isolate the cavity into a first cavity and a second cavity which are not connected to each other.

[0017] By adopting the above technical solution, the isolating element can block the first cavity and the second cavity, reduce the efficiency of heat transfer from the second cavity to the first cavity, and thus improve the ultimate tolerance temperature of the radio frequency admittance level switch.

[0018] In the above-mentioned specific implementation of the high temperature and high pressure radio frequency admittance level meter probe, the shell is provided with a first interface and a second interface, the first interface and the second interface are connected to a first cavity away from the end of the insulating and heat-insulating sleeve, and the first interface is connected to a cooling medium.

[0019] By adopting the above technical solution, the cooling medium is introduced from the first interface and flows out from the second interface, so as to cool the insulating and heat-insulating sleeve and the shell, thereby improving the ultimate tolerance temperature of the radio frequency admittance level switch.

[0020] In the above-mentioned specific implementation of the high-temperature and high-pressure radio frequency admittance level meter probe, the material of the insulating and heat-insulating sleeve is insulating glass.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The high-temperature and high-pressure radio frequency admittance level meter probe provided by the present invention includes a shell, an insulating heat-insulating sleeve and a detection conductor. The shell is provided with a cavity penetrating the shell along the axis; the insulating heat-insulating sleeve is accommodated in the cavity and the end thereof extends out from the shell, the insulating heat-insulating sleeve is hollow and the end thereof is closed; the detection conductor includes a spring, the spring is inserted into the insulating heat-insulating sleeve and the end thereof abuts against the insulating heat-insulating sleeve. After the temperature of the detection conductor changes, the spring can shrink or elongate, always maintaining the same length, and will not affect the measurement accuracy of the radio frequency admittance level meter probe. In addition, the elongation and contraction of the spring due to temperature changes can be converted into elastic potential energy, and the force applied by the spring to the insulating heat-insulating sleeve does not change much, and will not damage the insulating heat-insulating sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which: Figure 1It is a schematic diagram of the radio frequency admittance level meter probe provided by the present invention; Figure 2 It is a partial schematic diagram of the cross-sectional structure of the radio frequency admittance level meter probe provided by the present invention; Figure 3 It is a schematic diagram of the exploded structure of the radio frequency admittance level meter probe provided by the present invention; Figure 4 It is a partial structural cross-sectional view of another radio frequency admittance level meter probe provided by the present invention.

[0023] Description of reference numerals: 1. Shell; 11. Cavity; 111. First cavity; 112. Second cavity; 12. Receiving groove; 13. Heat sink; 14. Isolator; 2. Insulating and thermally insulating sleeve; 3. Detection conductor; 31. Hard part; 32. Spring; 4. Thermally insulating gasket; 5. Pressing ring; 6. Pressing piece; 61. Lock nut; 7. Insulating block; 8. Locking piece; 81. Positioning bolt; 82. Electrical connection bolt; 91. Cover cap; 92. Lead protection cover. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0025] It should be noted that in the description of the present invention, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0026] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "setting", and "connection" 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 direct connection, an indirect connection through an intermediate medium, or the internal connection of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In order to solve the drawbacks of the detection conductor in the existing radio frequency admittance level meter probe caused by high temperature, the present invention provides a high-temperature and high-pressure radio frequency admittance level meter probe, comprising: a shell, a cavity penetrating the shell is opened along the axis; an insulating and heat-insulating sleeve is accommodated in the cavity and the end thereof extends from the shell, the insulating and heat-insulating sleeve is hollow and the end thereof is closed; the detection conductor comprises a spring, the spring is inserted into the insulating and heat-insulating sleeve and the end thereof abuts against the insulating and heat-insulating sleeve.

[0028] The high temperature and high pressure radio frequency admittance level meter probes of some embodiments of the present disclosure are described below through specific examples.

[0029] like Figures 1 to 3 As shown, the high temperature and high pressure radio frequency admittance level meter probe includes a housing 1, a power supply module, an insulating and heat-insulating sleeve 2 and a detection conductor 3. The insulating and heat-insulating sleeve 2 is hollow and closed at the end, and the detection conductor 3 is arranged in the insulating and heat-insulating sleeve 2. The initial end of the insulating and heat-insulating sleeve 2 in which the detection conductor 3 is arranged is located in the housing 1, and the end extends out of the housing 1 to contact the medium to be measured. The power supply module is used to supply power to the detection conductor 3. The detection conductor 3 and the container wall containing the medium to be measured form a two-stage capacitor with a fixed spacing. After the material level in the container covers the insulating and heat-insulating sleeve 2, the medium and the air above the medium act as the filling between the capacitors. The radio frequency admittance level meter probe can emit a certain high-frequency radio wave to act on the detection conductor 3. As the level height of the medium changes, the electrical parameters (such as capacitance value and admittance value) between the detection conductor 3 and the container wall change, thereby causing the change of the radio wave acting on the detection conductor 3. According to the change of the radio wave, the level height of the medium can be analyzed and calculated.

[0030] The insulating and heat-insulating sleeve 2 in the high-temperature and high-pressure radio frequency admittance level meter probe provided by the present invention completely wraps the detection conductor 3 therein, so that the detection conductor 3 is separated from the medium to be measured. The insulating and heat-insulating sleeve 2 in contact with the conductor to be measured has a low heat conduction efficiency, which can effectively reduce the temperature conducted to the initial end of the radio frequency admittance level meter probe, thereby improving the ultimate heat resistance temperature of the radio frequency admittance level meter probe.

[0031] The insulating and heat-insulating sleeve 2 is made of insulating glass, such as phosphate glass or silicate glass.

[0032] The end of the shell 1 is fixedly connected to the container wall (such as threaded connection) so that the RF admittance level meter probe remains stable. The shell 1 is provided with a cavity 11 that penetrates the shell 1 along the axis. The initial end of the cavity 11 is a receiving groove 12. The diameter of the receiving groove 12 is larger than the diameter of the rest of the cavity 11, so that a limiting surface is formed at the bottom of the receiving groove 12. The initial end of the insulating and heat-insulating sleeve 2 is located in the receiving groove 12.

[0033] The receiving groove 12 is provided with a heat-insulating seal 4 and a pressure ring 5, which are inserted into the insulating heat-insulating sleeve 2 in sequence from the initial end thereof, so that the heat-insulating seal 4 and the pressure ring 5 are located between the insulating heat-insulating sleeve 2 and the housing 1. The initial end of the housing 1 is provided with a pressing member 6, at least part of which is located in the receiving groove 12 and connected to the housing 1 to force the heat-insulating seal 4 to abut against the bottom of the receiving groove 12. For example, the pressing member 6 is threadedly connected to the housing 1, and the pressing member 6 is gradually screwed into the receiving groove 12, and the pressing member 6 will squeeze the pressure ring 5 and the heat-insulating seal 4 close to the bottom of the receiving groove 12 until the heat-insulating seal 4 is tightly abutted against the bottom of the receiving groove 12. After the heat-insulating seal 4 abuts against the bottom of the receiving groove 12, it can seal the gap between the insulating heat-insulating sleeve 2 and the housing 1, prevent hot air from transferring heat upward from the gap between the insulating heat-insulating sleeve 2 and the housing 1, and also improve the pressure resistance of the RF admittance level meter probe.

[0034] The high temperature and high pressure radio frequency admittance level meter probe also includes an insulating block 7 and a locking piece 8, the insulating block 7 and the locking piece 8 are inserted into the pressing piece 6, the insulating block 7 is located between the locking piece 8 and the pressing piece 6, and the initial end of the detection conductor 3 is fixed to the locking piece 8. The insulating block 7 can insulate and isolate the locking piece 8 and the pressing piece 6 to prevent the detection conductor 3 from being electrically connected to the housing 1 through the locking piece 8 and the pressing piece 6. In addition, if the insulating block 7 is made of a heat-insulating material, the heat conduction efficiency between the locking piece 8 and the pressing piece 6 can be reduced, thereby reducing the temperature of the detection conductor 3, and then improving the extreme heat resistance temperature of the radio frequency admittance level switch.

[0035] The side wall of the pressing piece 6 is provided with a plurality of spacing grooves in the radial direction, so that the pressing piece 6 can be retracted inwardly. The outer peripheral surface of the pressing piece 6 is a tapered surface, wherein the diameter of the end away from the insulating and heat-insulating sleeve 2 gradually decreases. The outer periphery of the pressing piece 6 is provided with a lock nut 61, which is threadedly connected to the outer periphery of the pressing piece 6. As the lock nut 61 is gradually screwed in, the lock nut 61 compresses the pressing piece 6 to retract inwardly to compress the insulating block 7, thereby preventing the insulating block 7 from detaching from the pressing piece 6.

[0036] The detection conductor 3 of the radio frequency admittance level meter probe provided by the invention includes a hard part 31 and a spring 32, one end of the hard part 31 is connected to the spring 32, and the other end is fixed to the housing 1. Specifically, the hard part 31 is inserted into the locking member 8, and the positioning bolt 81 is screwed into the side wall of the locking member 8 to abut the hard part 31, thereby limiting the relative position relationship between the hard part 31 and the locking member 8, preventing the hard part 31 from being separated from the locking member 8, thereby achieving relative fixation of the hard part 31 and the housing 1. The side wall of the locking member 8 is also provided with an electrical connection bolt 82 for connecting an external conductor, and the external conductor is electrically connected to the hard part 31 by the electrical connection bolt 82, so as to supply power to the detection conductor 3.

[0037] The initial end of the spring 32 is connected to the hard part 31, and the end is in contact with the bottom of the internal space of the insulating and heat-insulating sleeve 2. The spring 32 is used as the main part of the detection conductor 3. After the temperature of the detection conductor 3 changes, the spring 32 can shrink or stretch, and always maintain the same length, which will not affect the measurement accuracy of the RF admittance level meter probe. In addition, the elongation and contraction of the spring 32 caused by temperature changes can be converted into elastic potential energy, and the force applied by the spring 32 to the insulating and heat-insulating sleeve 2 does not change much, and the insulating and heat-insulating sleeve 2 will not be damaged.

[0038] In addition, the extreme tolerance temperature of the radio frequency admittance level meter probe can also be increased by lowering the temperature of the shell 1. In a specific example of the present invention, a heat sink 13 is provided on the circumference of the shell 1 to accelerate the heat dissipation speed of the shell 1 and lower the temperature of the shell 1 to increase the extreme tolerance temperature of the radio frequency admittance level meter probe.

[0039] In addition, if Figure 4 As shown, an isolator 14 may also be provided in the cavity 11, and the isolator 14 is sleeved on the outside of the insulating and heat-insulating sleeve 2. The isolator 14 divides the cavity 11 into a first cavity 111 and a second cavity 112, and the first cavity 111 is far away from the end of the insulating and heat-insulating sleeve 2. The isolator 14 is configured to isolate the first cavity 111 and the second cavity 112, thereby reducing the efficiency of heat transfer from the second cavity 112 to the first cavity 111, thereby reducing the temperature of the housing 1 and the insulating and heat-insulating sleeve 2, thereby increasing the extreme tolerance temperature of the RF admittance level meter probe.

[0040] A first interface and a second interface may also be provided on the housing 1, and the first interface and the second interface are in communication with the first cavity 111, wherein the first interface is connected to a cooling medium. The cooling medium is introduced from the first interface and flows out from the second interface, thereby cooling the insulating and heat-insulating sleeve 2 and the housing 1, and increasing the extreme tolerance temperature of the RF admittance level meter probe. For example, the cooling medium is low-temperature or normal-temperature air, or water.

[0041] The initial end of the housing 1 is provided with a cap 91 and a lead protection cover 92. The cap 91 covers the initial end of the housing 1 to protect the internal components. The lead protection cover 92 covers the end of the cap 91 away from the housing 1 to protect the lead wires electrically connected to the detection conductor 3.

[0042] In summary, the high temperature and high pressure radio frequency admittance level meter probe provided by the present invention has at least the following advantages: (1) The spring 32 is used as the main part of the detection conductor 3. After the temperature of the detection conductor 3 changes, the spring 32 can shrink or stretch, always maintaining the same length, and will not affect the measurement accuracy of the RF admittance level meter probe; in addition, the elongation and contraction of the spring 32 caused by temperature changes can be converted into elastic potential energy, and the force applied by the spring 32 to the insulating and heat-insulating sleeve 2 does not change much, and will not damage the insulating and heat-insulating sleeve 2.

[0043] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A high temperature and high pressure radio frequency admittance level meter probe, characterized in that: include: A shell (1) having a cavity (11) extending along an axis and penetrating the shell (1); An insulating and heat-insulating sleeve (2) is accommodated in the cavity (11) and has its end extending out of the shell (1); the insulating and heat-insulating sleeve (2) is hollow and has a closed end; The detection conductor (3) comprises a spring (32), wherein the spring (32) is inserted into the insulating and heat-insulating sleeve (2) and the end of the spring (32) abuts against the insulating and heat-insulating sleeve (2).

2. The high temperature and high pressure radio frequency admittance level meter probe according to claim 1, characterized in that: The detection conductor also includes a hard part (31), which is connected to an end of the spring (32) away from the insulating and heat-insulating sleeve (2) and is fixed to the housing (1).

3. The high temperature and high pressure radio frequency admittance level meter probe according to claim 1, characterized in that: The top of the cavity (11) is a receiving groove (12), and the initial end of the insulating heat-insulating sleeve (2) is located in the receiving groove (12); the high-temperature and high-pressure radio frequency admittance level meter probe also includes a pressing piece (6) and a heat-insulating sealing pad (4), the heat-insulating sealing pad (4) is located in the receiving groove (12) and is sleeved on the initial end of the insulating heat-insulating sleeve (2), and at least a part of the pressing piece (6) is located in the receiving groove (12) and is connected to the shell (1) to force the heat-insulating sealing pad (4) to abut against the bottom of the receiving groove (12).

4. The high temperature and high pressure radio frequency admittance level meter probe according to claim 3, characterized in that: The high-temperature and high-pressure radio frequency admittance level meter probe further comprises an insulating block (7) and a locking piece (8), wherein the insulating block (7) and the locking piece (8) are inserted into the pressing piece (6), the insulating block (7) is located between the locking piece (8) and the pressing piece (6), and the initial end of the detection conductor (3) is fixed to the locking piece (8).

5. The high temperature and high pressure radio frequency admittance level meter probe according to claim 1, characterized in that: The outer periphery of the housing (1) is provided with heat sinks (13).

6. The high temperature and high pressure radio frequency admittance level meter probe according to claim 1, characterized in that: An isolating member (14) is disposed in the cavity (11); the isolating member (14) is sleeved on the outside of the insulating and heat-insulating sleeve (2) and is configured to isolate the cavity (11) into a first cavity (111) and a second cavity (112) that are not connected to each other.

7. The high temperature and high pressure radio frequency admittance level meter probe according to claim 6, characterized in that: The shell (1) is provided with a first interface and a second interface, the first interface and the second interface are in communication with a first cavity (111) away from the end of the insulating and heat-insulating sleeve (2), and the first interface is connected to a cooling medium.

8. The high temperature and high pressure radio frequency admittance level meter probe according to claim 1, characterized in that: The insulating and heat-insulating sleeve (2) is made of heat-insulating glass.

Images