Thermocouple

Abstract

The utility model relates to the technical field of temperature measuring equipment, in particular to a thermocouple, which comprises a thermocouple wire, a protective sleeve sleeved on the outer side of the thermocouple wire, a positioning sleeve sleeved on the outer side of the lower part of the protective sleeve, a knocking pressing plate fixed on the outer side of the upper part of the protective sleeve, and a wiring mechanism connected to the upper end of the protective sleeve and electrically connected with the thermocouple wire. The positioning sleeve comprises a positioning section and a connecting section which are sequentially arranged from bottom to top, the middle of the connecting section is fixed to the outer side of the protective sleeve through a crimping process, and the upper end of the connecting section is welded to the outer side of the protective sleeve; when the thermocouple is installed or maintained, the protective sleeve can be moved by knocking the knocking pressing plate, so that the protective sleeve can be conveniently taken out or installed; and the middle part of the connecting section is fixed on the outer side of the protective sleeve through a crimping process, so that the connecting strength between the positioning sleeve and the protective sleeve is improved, and the risk that a welding seam between the positioning sleeve and the protective sleeve is cracked due to knocking the knocking pressing plate is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature measuring equipment, in particular to a thermocouple. Background Art

[0002] Thermocouple is a commonly used temperature measuring element. There are a total of 13 original thermocouples used for the annular temperature thermocouples between the compressor turbine and the power turbine stage of the Siemens SGT-400 gas turbine. All 13 thermocouples are Siemens brand N-graded thermocouples. All 13 thermocouples are imported components and are relatively expensive.

[0003] like Figure 1 As shown, the thermocouple includes a thermocouple wire, a protective sleeve sleeved on the outside of the thermocouple wire, a positioning sleeve sleeved on the outside of the lower part of the protective sleeve, and a connection box connected to the upper end of the protective sleeve for connecting the thermocouple wire in the protective sleeve to an external circuit. The casing of the gas turbine is provided with three coaxially arranged thermocouple mounting holes. When installing the thermocouple, the positioning sleeve needs to be inserted into the three thermocouple mounting holes so that the protective sleeve extending out of the lower end of the positioning sleeve can be extended into the casing.

[0004] Since the casing is in a high temperature state of over 800°C for a long time during operation, the coaxiality of the three coaxially arranged thermocouple mounting holes will increase due to thermal expansion and contraction. The increase in coaxiality of the three thermocouple mounting holes will cause the locating sleeves to get stuck during the process of inserting or removing them from the thermocouple mounting holes, making it difficult for the locating sleeves to smoothly penetrate or remove them from the thermocouple mounting holes, making the installation and maintenance of the thermocouples very difficult. In actual operation, it is often necessary to knock the protective sleeve to install the positioning sleeve in place; however, the upper part of the protective sleeve is a smooth columnar structure. When knocking the protective sleeve, workers often need to use pliers to clamp the outer wall of the protective sleeve, relying on the friction between the pliers and the outer wall of the protective sleeve to push the protective sleeve to move. The pliers and the protective sleeve are prone to sliding, which increases the difficulty of installing or maintaining the thermocouple; in addition, the end of the positioning sleeve is fixed to the outside of the protective sleeve by welding. In the process of knocking the protective sleeve downward, the positioning sleeve is hindered by the hole wall of the mounting hole and is subjected to an upward thrust, and the protective sleeve is subjected to a downward thrust under the action of the clamp; therefore, the weld between the positioning sleeve and the protective sleeve will be subjected to a large axial shear force, and the operating temperature of the casing is high, and the temperature of the weld between the positioning sleeve and the protective sleeve is high. Under the action of high temperature and large axial shear force, the weld between the positioning sleeve and the protective sleeve is prone to cracking and failure, resulting in the separation of the positioning sleeve and the protective sleeve. If the positioning sleeve separated from the protective sleeve is stuck in each mounting hole and difficult to remove, it will greatly increase the difficulty of installing and maintaining the thermocouple. Utility Model Content

[0005] The technical problem to be solved by the utility model is that the existing thermocouple is not convenient for removing or inserting the protective sleeve during installation or maintenance of the thermocouple, and the weld between the positioning sleeve and the protective sleeve is easily invalidated due to knocking, causing the positioning sleeve to be stuck in the thermocouple installation hole.

[0006] In order to achieve the above-mentioned object, the utility model provides a thermocouple, comprising a thermocouple wire, a protective sleeve sleeved outside the thermocouple wire, a positioning sleeve sleeved outside the lower part of the protective sleeve, a knocking plate fixed outside the upper part of the protective sleeve, and a wiring mechanism connected to the upper end of the protective sleeve and electrically connected to the thermocouple wire;

[0007] The positioning sleeve comprises a positioning section and a connecting section which are arranged in sequence from bottom to top, the middle portion of the connecting section is fixed to the outside of the protective sleeve by a crimping process, and the upper end of the connecting section is welded to the outside of the protective sleeve.

[0008] As a preferred solution, the protective sleeve comprises a first sleeve and a second sleeve integrally formed from bottom to top, the outer diameter of the second sleeve is larger than the outer diameter of the second sleeve, and the positioning sleeve is arranged at the lower part of the second sleeve;

[0009] The positioning sleeve also includes a reinforcement section integrally formed at the lower end of the connecting section, and the reinforcement section is sleeved on the upper part of the first sleeve.

[0010] As a preferred solution, the knocking plate is fixed to the upper outer side of the second sleeve, and a mounting assembly for connecting the second sleeve to the casing of the gas turbine is fixed to the second sleeve at a position between the knocking plate and the positioning sleeve.

[0011] As a preferred solution, the mounting assembly includes a reinforcing sleeve fixedly sleeved on the outside of the second sleeve and a pipe joint nut sleeved on the outside of the second sleeve, and the casing is connected with a pipe joint matching the pipe joint nut.

[0012] As a preferred embodiment, the knocking plate is a circular plate fixedly mounted on the outside of the second sleeve, the lower end of the knocking plate is welded to the upper end of the reinforcement sleeve, and the outer diameter of the knocking plate is larger than the outer contour of the pipe nut.

[0013] As a preferred solution, the length of the lower end of the first sleeve extending from the lower end of the reinforcement section is greater than or equal to 7 mm and less than or equal to 12 mm.

[0014] As a preferred solution, the connecting section clamps the protective sleeve through a six-sided cold clamping process.

[0015] As a preferred solution, the upper portion of the connecting section is fixed to the outer side of the protective sleeve by a crimping process, and the lower portion of the connecting section is provided with a positioning portion protruding outward.

[0016] As a preferred solution, the positioning section is used to be inserted into the thermocouple mounting hole of the casing, and the single-sided matching clearance between the positioning section and the thermocouple mounting hole is greater than or equal to 0.3 mm and less than or equal to 0.5 mm.

[0017] As a preferred solution, the wiring mechanism includes a rubber sleeve fixed to the upper end of the protective sleeve and a compensation wire arranged in the rubber sleeve, and the upper end of the electric couple wire penetrates into the rubber sleeve and is welded to the compensation wire.

[0018] Compared with the prior art, the thermocouple of the utility model embodiment has the following beneficial effects: the thermocouple of the utility model comprises an electric couple wire, a protective sleeve sleeved on the outside of the electric couple wire, a positioning sleeve sleeved on the outside of the lower part of the protective sleeve, a knocking plate fixed on the outside of the upper part of the protective sleeve, and a wiring mechanism connected to the upper end of the protective sleeve and electrically connected to the electric couple wire; the positioning sleeve comprises a positioning section and a connecting section arranged in sequence from bottom to top, the middle part of the connecting section is fixed to the outside of the protective sleeve by a crimping process, and the upper end of the connecting section is welded to the outside of the protective sleeve; when installing or maintaining the thermocouple, the protective sleeve can be moved by knocking the knocking plate, which is convenient for taking out or loading the protective sleeve; the middle part of the connecting section is fixed to the outside of the protective sleeve by a crimping process, which improves the connection strength between the positioning sleeve and the protective sleeve, reduces the shear force on the weld between the positioning sleeve and the protective sleeve during the knocking of the knocking plate, and reduces the risk of cracking of the weld between the positioning sleeve and the protective sleeve due to knocking the knocking plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an existing thermocouple;

[0020] Figure 2 It is a front view of the thermocouple of the utility model;

[0021] Figure 3 It is a cross-sectional view of the thermocouple of the utility model;

[0022] In the figure, 100, junction box, 1, electric couple wire, 2, protective sleeve, 21, first sleeve, 22, second sleeve, 3, positioning sleeve, 31, positioning section, 32, connecting section, 321, positioning part, 33, reinforcement section, 4, knocking pressure plate, 5, wiring mechanism, 51, rubber sleeve, 52, compensation wire, 6, installation assembly, 61, reinforcement sleeve, 611, first stop ring, 62, pipe joint nut, 621, second stop ring, 63, pipe joint. DETAILED DESCRIPTION

[0023] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0024] like Figure 2 , Figure 3 As shown, a preferred embodiment of the thermocouple of the utility model comprises a protective sleeve 2 for sleeved on the outside of the thermocouple wire 1, a positioning sleeve 3 sleeved on the outside of the lower part of the protective sleeve 2, a knocking plate 4 fixed on the outside of the upper part of the protective sleeve 2, and a wiring mechanism 5 connected to the upper end of the protective sleeve 2 and electrically connected to the thermocouple wire 1;

[0025] The positioning sleeve 3 includes a positioning section 31 and a connecting section 32 arranged in sequence from bottom to top. The middle of the connecting section 32 is fixed to the outside of the protective sleeve 2 by a crimping process, and the upper end of the connecting section 32 is welded to the outside of the protective sleeve 2.

[0026] Specifically, when installing or maintaining the thermocouple, the protective sleeve 2 can be moved by knocking the knocking pressure plate 4, which is convenient for removing or installing the protective sleeve 2; the middle part of the connecting section 32 is fixed to the outside of the protective sleeve 2 by a crimping process, which improves the connection strength between the positioning sleeve 3 and the protective sleeve 2, reduces the shear force on the weld between the positioning sleeve 3 and the protective sleeve 2 during the knocking of the knocking pressure plate 4, and reduces the risk of cracking of the weld between the positioning sleeve 3 and the protective sleeve 2 due to knocking the knocking pressure plate 4.

[0027] The protective sleeve 2 includes a first sleeve 21 and a second sleeve 22 integrally formed from bottom to top, the outer diameter of the second sleeve 22 is larger than the outer diameter of the second sleeve 22, the positioning sleeve 3 is sleeved on the lower part of the second sleeve 22, and the positioning sleeve 3 also includes a reinforcing section 33 integrally formed at the lower end of the connecting section 32, and the reinforcing section 33 is sleeved on the upper part of the first sleeve 21. Specifically, the first sleeve 21 with a smaller diameter is arranged at the lower end of the protective sleeve 2, which can enhance the measurement accuracy of the electric couple wire 1 located in the protective sleeve 2, and the reinforcing section 33 is sleeved on the outer side of the first sleeve 21, which can increase the strength of the first sleeve 21 and avoid the transition part between the first sleeve 21 and the second sleeve 22 from being broken due to stress; in addition, during the operation of the gas turbine, the first sleeve 21 will be washed by the high-temperature mixed gas after the combustion of the gas, and the provision of the reinforcing section 33 can increase the strength of the first sleeve 21 and avoid the first sleeve 21 from being broken due to the washing of the high-temperature mixed gas.

[0028] In this embodiment, in order to facilitate the connection of the thermocouple at the installation position of the gas turbine, the knocking plate 4 is fixed to the upper outer side of the second sleeve 22, and the second sleeve 22 is fixed with a mounting assembly 6 for connecting the second sleeve 22 to the gas turbine at a position between the knocking plate 4 and the positioning sleeve 3. Specifically, the knocking plate 4 is arranged on the upper outer side of the second sleeve 22, and the mounting assembly 6 is arranged between the knocking plate 4 and the positioning sleeve 3. After the mounting assembly 6 is connected to the gas turbine, the knocking plate 4 is located on the outer side of the mounting assembly 6, which is convenient for the operator to perform the knocking operation.

[0029] Furthermore, the mounting assembly 6 comprises a reinforcing sleeve 61 fixedly sleeved on the outside of the second sleeve 22 and a pipe union nut 62 sleeved on the outside of the reinforcing sleeve 61, and the gas turbine is connected with a pipe joint 63 matching the pipe union nut 62. Specifically, as Figure 3 As shown, a first stop ring 611 is fixed to the outer side of the reinforcing sleeve 61, a pipe nut 62 is provided with a threaded hole, and a second stop ring 621 is provided on the inner side of the upper end of the threaded hole; the second sleeve 22 is passed through the tube cavity of the pipe joint 63, and an external thread is provided on the outer side of the pipe joint 63. The pipe joint 63 is moved downward so that the threaded hole and one end of the pipe joint 63 are connected to the casing of the gas turbine, and the other end of the pipe joint 63 is provided with an external thread. The pipe joint 62 is rotated to screw the threaded hole of the pipe joint 62 with the rising external thread until the first stop ring 611 abuts against the second stop ring 621, and the thermocouple can be connected to the desired position.

[0030] In this embodiment, the knocking plate 4 is a circular plate fixedly sleeved on the outside of the second sleeve 22, the lower end of the knocking plate 4 is welded to the upper end of the reinforcing sleeve 61, and the outer diameter of the circular plate is larger than the outer profile of the pipe nut 62. Specifically, the reinforcing sleeve 61 is fixed to the outside of the second sleeve 22, and the lower end of the knocking plate 4 is welded to the upper end of the reinforcing sleeve 61, thereby improving the connection strength between the knocking plate 4 and the second sleeve 22.

[0031] In this embodiment, in order to ensure the measurement accuracy of the thermocouple and reduce the scouring force of the high-temperature mixed gas on the first sleeve 21, the length of the lower end of the first sleeve 21 extending from the lower end of the reinforcement section 33 is greater than or equal to 7 mm and less than or equal to 12 mm. Specifically, if the length of the first sleeve 21 extending from the lower end of the reinforcement section 33 is too short, the depth of the electric couple wire 1 in the first sleeve 21 extending into the cavity to be measured is too shallow, which will lead to insufficient measurement accuracy of the thermocouple; if the length of the lower end of the first sleeve 21 extending from the lower end of the reinforcement section 33 is too long, the scouring force of the high-temperature mixed gas on the first sleeve 21 will increase, so that the first sleeve 21 is easy to break. In this embodiment, the length of the lower end of the first sleeve 21 extending from the lower end of the reinforcement section 33 is greater than or equal to 7 mm and less than or equal to 12 mm, which not only ensures the measurement accuracy of the thermocouple, but also reduces the scouring force of the high-temperature mixed gas on the first sleeve 21, and improves the service life of the thermocouple.

[0032] In this embodiment, the connection section 32 clamps the protective cover 2 by a six-sided cold clamping process. Specifically, when the connection section 32 is crimped to the outside of the protective cover 2, a crimping die is used for crimping. The structure of the crimping die is similar to that of a cable connector crimping die. After the connection section 32 is crimped, a recessed portion is formed on the outside of the protective cover 2, and a raised portion is generated on the inside of the connection section 32. The raised portion is stuck in the recessed portion, thereby improving the axial shear strength between the connection section 32 and the protective cover 2.

[0033] In order to facilitate the positioning of the installation depth of the positioning section 31 and ensure the length of the first sleeve 21 extending into the chamber to be measured, the upper part of the connecting section 32 is fixed to the outside of the protective sleeve 2 by a crimping process, and the lower part of the connecting section 32 is provided with a positioning portion 321 protruding outward. Specifically, the positioning portion 321 is an annular flange, which abuts against the end of the thermocouple installation hole to achieve the positioning of the thermocouple installation depth.

[0034] In this embodiment, in order to avoid the inability of the positioning section 31 to be inserted into the thermocouple mounting holes due to the coaxiality differences between the thermocouple mounting holes, the positioning section 31 is used to be inserted into the thermocouple mounting hole of the casing, and the single-sided matching clearance between the positioning section 31 and the thermocouple mounting hole is greater than or equal to 0.3 mm and less than or equal to 0.5 mm.

[0035] like Figure 1 As shown, the imported thermocouple is provided with a junction box 100 at the upper end of the protective cover 2, and a wiring terminal is provided in the junction box 100. The galvanic wire 1 and the external wire are connected through the wiring terminal. The junction box 100 is fixed at the upper end of the protective cover 2. The junction box 100 needs to occupy a certain space. There are brackets or compressed air pipes near some thermocouple installation positions. To ensure the smooth opening and closing of the junction box 100, during the installation of the thermocouple, the junction box 100 needs to be away from the bracket or the compressed air pipe, resulting in a limited installation method of the thermocouple; and, the galvanic wire 1 and the external wire are connected through the transition connector, the wiring terminal, and a failure of the wiring terminal may cause a failure of the thermocouple; in this embodiment, the wiring mechanism 5 includes a rubber sleeve 51 fixed to the upper end of the protective cover 2 and a compensation wire 52 arranged in the rubber sleeve 51, and the upper end of the galvanic wire 1 is inserted into the rubber sleeve 51 and welded to the compensation wire 52.

[0036] When installing the thermocouple, the rubber sleeve 51 can be bent to avoid the bracket or compressed air pipe near the thermocouple installation position, which is convenient for the installation of the thermocouple. In addition, the compensation wire 52 is welded to the thermocouple wire 1, and there is no need to set a terminal between the thermocouple wire 1 and the compensation wire 52, thereby avoiding the influence of the terminal failure on the thermocouple and improving the stability of the thermocouple.

[0037] In summary, the thermocouple of the utility model comprises a thermocouple wire 1, a protective sleeve 2 sleeved on the outer side of the thermocouple wire 1, a positioning sleeve 3 sleeved on the outer side of the lower part of the protective sleeve 2, a knocking plate 4 fixed on the outer side of the upper part of the protective sleeve 2, and a wiring mechanism 5 connected to the upper end of the protective sleeve 2 and electrically connected to the thermocouple wire 1; the positioning sleeve 3 comprises a positioning section 31 and a connecting section 32 arranged in sequence from bottom to top, the middle part of the connecting section 32 is fixed to the outer side of the protective sleeve 2 by a crimping process, and the upper end of the connecting section 32 is connected to the protective sleeve 2 is welded on the outside; when installing or maintaining the thermocouple, the protective sleeve 2 can be moved by knocking the knocking plate 4, which is convenient for taking out or loading the protective sleeve 2; the middle part of the connecting section 32 is fixed to the outside of the protective sleeve 2 by the crimping process, which improves the connection strength between the positioning sleeve 3 and the protective sleeve 2, reduces the shear force on the weld between the positioning sleeve 3 and the protective sleeve 2 during the knocking of the knocking plate 4, and reduces the risk of cracking of the weld between the positioning sleeve 3 and the protective sleeve 2 due to the knocking of the knocking plate 4. The use of the thermocouple of the utility model realizes the domestic substitution of the annular temperature thermocouple between the compressor turbine and the power turbine stage of the Siemens SGT-400 gas turbine, which reduces the procurement cost of the annular temperature thermocouple between the compressor turbine and the power turbine stage of the Siemens SGT-400 gas turbine by more than 70%, and is more convenient for the installation and maintenance of the thermocouple, thereby improving the service life of the thermocouple and increasing the service life of the thermocouple.

[0038] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A thermocouple, characterized in that: It comprises a galvanic wire (1), a protective sleeve (2) sleeved on the outside of the galvanic wire (1), a positioning sleeve (3) sleeved on the outside of the lower part of the protective sleeve (2), a knocking plate (4) fixed on the outside of the upper part of the protective sleeve (2), and a wiring mechanism (5) connected to the upper end of the protective sleeve (2) and electrically connected to the galvanic wire (1); The positioning sleeve (3) comprises a positioning section (31) and a connecting section (32) arranged in sequence from bottom to top, the middle portion of the connecting section (32) is fixed to the outside of the protective sleeve (2) by a crimping process, and the upper end of the connecting section (32) is welded to the outside of the protective sleeve (2).

2. The thermocouple according to claim 1, characterized in that The protective sleeve (2) comprises a first sleeve (21) and a second sleeve (22) which are integrally formed from bottom to top, the outer diameter of the second sleeve (21) is larger than the outer diameter of the second sleeve (22), and the positioning sleeve (3) is sleeved on the lower part of the second sleeve (22); The positioning sleeve (3) further comprises a reinforcing section (33) integrally formed at the lower end of the connecting section (32), and the reinforcing section (33) is sleeved on the upper part of the first sleeve (21).

3. The thermocouple according to claim 2, characterized in that The knocking plate (4) is fixed to the upper outer side of the second sleeve (22); and a mounting assembly (6) for connecting the second sleeve (22) to the casing of the gas turbine is fixed to the second sleeve (22) at a position between the knocking plate (4) and the positioning sleeve (3).

4. The thermocouple according to claim 3, characterized in that The mounting assembly (6) comprises a reinforcing sleeve (61) fixedly sleeved on the outside of the second sleeve (22) and a pipe joint nut (62) sleeved on the outside of the second sleeve (22); the casing is connected to a pipe joint (63) matching the pipe joint nut (62).

5. The thermocouple according to claim 4, characterized in that The knocking plate (4) is a circular plate fixedly sleeved on the outside of the second sleeve (22), the lower end of the knocking plate (4) is welded to the upper end of the reinforcing sleeve (61), and the outer diameter of the knocking plate (4) is larger than the outer profile of the pipe joint nut (62).

6. The thermocouple according to claim 2, characterized in that The length by which the lower end of the first sleeve (21) protrudes from the lower end of the reinforcement section (33) is greater than or equal to 7 mm and less than or equal to 12 mm.

7. The thermocouple according to claim 1, characterized in that The connecting section (32) clamps the protective sleeve (2) through a six-sided cold clamping process.

8. The thermocouple according to claim 1, characterized in that The upper portion of the connecting section (32) is fixed to the outer side of the protective sleeve (2) by means of a crimping process, and the lower portion of the connecting section (32) is provided with a positioning portion (321) protruding outward.

9. The thermocouple according to claim 1, characterized in that The positioning section (31) is used to be inserted into the thermocouple mounting hole of the casing, and the single-side matching clearance between the positioning section (31) and the thermocouple mounting hole is greater than or equal to 0.3 mm and less than or equal to 0.5 mm.

10. The thermocouple according to claim 1, characterized in that The wiring mechanism (5) comprises a rubber sleeve (51) fixed to the upper end of the protective sleeve (2) and a compensation wire (52) arranged in the rubber sleeve (51); the upper end of the galvanic wire (1) penetrates into the rubber sleeve (51) and is welded to the compensation wire (52).

Images