Thermocouple sleeve circular seam installing and welding structure

Abstract

The utility model relates to the technical field of pressure vessel manufacturing, in particular to a thermocouple sleeve circular seam installing and welding structure, which comprises a first sleeve and a second sleeve which have the same inner diameter and are coaxial, a positioning ring is formed at the end part of the first sleeve, an annular positioning groove is arranged on the inner wall of the end part of the second sleeve, and the positioning ring is inserted into the positioning groove. A gap is reserved between the end face of the positioning ring and the positioning groove in the axial direction. A first inclined face is formed at the joint of the outer wall of the first sleeve and the positioning ring, a second inclined face is formed at the end of the second sleeve, and the first inclined face, the outer wall of the positioning ring and the second inclined face define an annular groove flaring outwards. Compared with the prior art, the device has the advantages of simplicity in operation, easiness in accurate positioning and assembling, material cost saving, high universality and the like. And after welding, the inner wall of the circumferential weld is formed flatly and has no weld reinforcement, the inner diameter does not need to additionally treat the reinforcement, the inner diameter size of the sleeve is effectively controlled, and the thermocouple can penetrate smoothly and unobstructed when inserted and assembled.

Description

Technical Field

[0001] The utility model relates to the technical field of pressure vessel manufacturing, and particularly relates to a circumferential seam assembly welding structure of a thermocouple sleeve. Background Art

[0002] In a pressure vessel, it is usually necessary to measure process variables, such as the temperature of a process fluid, and use this information to control or otherwise monitor an industrial process. One technique for measuring process temperature is through the use of a process variable transmitter that includes a temperature sensor. The temperature sensor is thermally coupled to the temperature to be measured by means of a so-called "thermocouple sleeve" that extends into the process fluid. A thermocouple is a common temperature measuring device in modern industry. The strength of a thermocouple device is not high, and the temperature of a medium is usually measured through a protective sleeve. Therefore, the performance of the protective sleeve will directly affect the service life and working stability of the thermocouple. As a device that directly contacts the medium, the sleeve is affected by the medium temperature, pressure, erosion, etc. Its material and shape design will directly affect the service life of the sleeve. Especially under the contemporary industrial high-temperature and high-pressure environment, the requirements for sleeves are gradually increasing, and the phenomenon of leakage of actually applied sleeves is gradually increasing. Leakage will affect the service life and working stability of the thermocouple, and in severe cases, it will even endanger the system and personal safety.

[0003] For example, the Chinese patent document with the publication number CN108593125B discloses a protective sleeve applied to the installation and protection of a thermocouple. This sleeve includes a steel pipe I and a steel pipe II connected by butt welding, and an inner plate is provided at the bottom of the weld; at the other end of the steel pipe I, a joint for threadedly connecting the thermocouple is welded, and a purging interface is welded on the side; at the other end of the steel pipe II, an end plate with end vent holes is welded, and evenly distributed oblong through holes are machined on the side. The material of the steel pipe II is selected as a high-temperature nickel-based alloy resistant to high-temperature oxidation, and a wear-resistant layer with a thickness of 0.1 - 0.5 mm and made of metal oxide as raw material is produced on the outer surface by thermal spraying process. The purging interface is connected to nitrogen or compressed air. This protective sleeve effectively protects the thermocouple, enables the thermocouple to work in a space free from impact and wear, improves the service life of the thermocouple, and reduces the replacement times and consumption of the thermocouple.

[0004] For the circumferential seam welding between two sections of steel pipes of the sleeve, using a conventional welding method, after the circumferential seam welding of the two sections of steel pipes, the weld cools and shrinks, and the ends of the two sections of steel pipes assembled by welding approach and squeeze each other, causing the welded joint of the two sections of steel pipes to arch inward, and further resulting in an excessive weld reinforcement height on the inner wall and the inability to assemble the thermocouple. Summary of the Invention

[0005] In view of all or part of the above technical problems existing in the prior art, the utility model provides a circumferential seam assembly welding structure of a thermocouple sleeve.

[0006] To achieve the above object, the utility model provides the following technical solutions:

[0007] A circumferential seam group welding structure for a thermocouple sleeve is provided, which includes a first sleeve and a second sleeve with equal inner diameters and coaxial. The outer diameter of the end of the first sleeve is reduced to form a positioning ring, and an annular positioning groove is formed on the inner wall of the end of the second sleeve. The positioning ring is inserted into the positioning groove along the axial direction, and there is a gap in the axial direction between the end face of the positioning ring and the root of the positioning groove; a first inclined surface is formed at the connection between the outer wall of the first sleeve and the positioning ring, and a second inclined surface is formed at the end of the second sleeve. The first inclined surface, the outer wall of the positioning ring and the second inclined surface enclose an annular groove opening outward.

[0008] Specifically, the size of the gap is 0.8 - 2 mm.

[0009] Specifically, the size of the gap is 1 mm.

[0010] Specifically, after welding, the groove is filled with solder, and the solder is flush with the outer walls of the first sleeve and the second sleeve.

[0011] Specifically, the outer diameter of the positioning ring is equal to the inner diameter of the positioning groove.

[0012] Specifically, the wall thickness of the positioning ring and the radial depth of the positioning groove are 1.5 - 2.5 mm.

[0013] Specifically, the wall thickness of the positioning ring and the radial depth of the positioning groove are 2 mm.

[0014] Specifically, the inclination angles of the first inclined surface and the second inclined surface are 25° - 45°.

[0015] Specifically, the inclination angles of the first inclined surface and the second inclined surface are 30°.

[0016] Specifically, the outer diameters of the first sleeve and the second sleeve are equal; and / or: the positioning ring, the first inclined surface, the positioning groove and the second inclined surface are formed by turning and milling.

[0017] Advantages of the present utility model:

[0018] The circumferential seam group welding structure of the thermocouple sleeve of the present utility model, compared with the prior art, the positioning ring and the positioning groove are inserted and positioned with each other, having the advantages of simple operation, easy precise positioning and assembly, and saving material costs. Moreover, there is a gap between the positioning ring and the positioning groove along the axial direction, leaving space for the shrinkage during cooling after welding. Therefore, there will be no phenomenon of extrusion and arching after welding. The inner wall of the circumferential weld is formed flat and there is no weld reinforcement. The inner diameter does not need to be additionally processed for the weld reinforcement, effectively controlling the inner diameter size of the sleeve, and facilitating the smooth insertion of the thermocouple during assembly. Description of the drawings

[0019] Figure 1 It is a schematic structural diagram of the first sleeve and the second sleeve in the embodiment before assembly.

[0020] Figure 2 Schematic diagram of the structure of the first sleeve and the second sleeve in the embodiment after assembly and before welding.

[0021] Figure 3 Schematic diagram of the structure of the first sleeve and the second sleeve in the embodiment after welding.

[0022] Reference numerals:

[0023] First sleeve 1, positioning ring 11, first inclined surface 12;

[0024] Second sleeve 2, positioning groove 21, second inclined surface 22;

[0025] Gap 3, groove opening 4, solder 5. Detailed implementation manners

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0027] A circumferential seam group welding structure of a thermocouple sleeve in this embodiment is as Figures 1 to 3 shown, including a first sleeve 1 and a second sleeve 2 with equal inner and outer diameters and coaxial. The outer diameter of the end of the first sleeve 1 is reduced to form a positioning ring 11. An annular positioning groove 21 is formed in the inner wall of the end of the second sleeve 2. The positioning ring 11 is axially inserted into the positioning groove 21, and a gap 3 is left axially between the end face of the positioning ring 11 and the root of the positioning groove 21. The size of the gap 3 is 0.8 - 2 mm, preferably 1 mm, and the actual value can be adjusted according to needs. During assembly, the positioning ring 11 is inserted into the positioning groove 21 until the positioning ring 11 axially abuts against the positioning groove 21, and then the first sleeve 1 retreats to leave the gap 3. In this embodiment, the outer diameter of the positioning ring 11 is equal to the inner diameter of the positioning groove 21. In practice, the outer diameter of the positioning ring 11 can be slightly smaller than the inner diameter of the positioning groove 21 to facilitate their sliding fit.

[0028] Specifically, the wall thickness of the positioning ring 11 and the radial depth of the positioning groove 21 are 1.5 - 2.5 mm. Preferably 2 mm. In practice, the value can be adjusted according to the wall thickness of the sleeve.

[0029] In this embodiment, a first inclined surface 12 is formed at the junction between the outer wall of the first sleeve 1 and the positioning ring 11, and a second inclined surface 22 is formed at the end of the second sleeve 2. The first inclined surface 12, the outer wall of the positioning ring 11 and the second inclined surface 22 enclose an outwardly flared annular groove opening 4. The inclination angles of the first inclined surface 12 and the second inclined surface 22 are 25° - 45°, preferably 30°. In practice, the positioning ring 11, the first inclined surface 12, the positioning groove 21 and the second inclined surface 22 are formed by turning and milling.

[0030] After Figure 2 assembly, solder 5 is welded at the groove 4 to form a structure as shown in Figure 3 the figure. After welding, the groove 4 is filled with solder 5, and the solder 5 is polished to be flush with the outer walls of the first sleeve 1 and the second sleeve 2.

[0031] Compared with the prior art, the positioning ring 11 and the positioning groove 21 are inserted into each other for positioning, which has the advantages of simple operation, easy precise positioning and assembly, and material cost saving. Moreover, a gap 3 is left between the positioning ring 11 and the positioning groove 21 along the axial direction, leaving space for the shrinkage during cooling after welding (the first sleeve 1 and the second sleeve 2 approach each other). Therefore, there will be no extrusion and arching at the weld after welding. The inner wall of the circumferential weld is flat after welding and there is no weld reinforcement. The inner diameter does not need to be additionally processed for the weld reinforcement, effectively controlling the inner diameter size of the sleeve and facilitating the smooth insertion of the thermocouple during assembly.

[0032] In the description of the present invention, it is obvious that the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the above detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the present invention to be protected, but only represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0034] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "arranged", "connected" and "coupled" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection. It may be a mechanical connection or an electrical connection. It may be directly connected or indirectly connected through an intermediate medium, and may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

Claims

1. A thermocouple sleeve annular welded structure, characterized in that: The invention comprises a first sleeve (1) and a second sleeve (2) of equal inner diameter and coaxial. The outer diameter of the end of the first sleeve (1) is reduced to form a positioning ring (11). The inner wall of the end of the second sleeve (2) is provided with an annular positioning groove (21). The positioning ring (11) is inserted into the positioning groove (21) along the axial direction, and a gap (3) is left between the end face of the positioning ring (11) and the root of the positioning groove (21) in the axial direction. A first inclined surface (12) is formed at the connection between the outer wall of the first sleeve (1) and the positioning ring (11), and a second inclined surface (22) is formed at the end of the second sleeve (2). The first inclined surface (12), the outer wall of the positioning ring (11) and the second inclined surface (22) form an annular groove (4) that expands outward.

2. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: The size of the gap (3) is 0.8 to 2 mm.

3. The thermocouple sleeve annular welded structure according to claim 2, characterized in that: The size of the gap (3) is 1 mm.

4. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: After welding, the groove (4) is filled with solder (5), and the solder (5) is flush with the outer walls of the first sleeve (1) and the second sleeve (2).

5. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: The outer diameter of the positioning ring (11) is equal to the inner diameter of the positioning groove (21).

6. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: The wall thickness of the positioning ring (11) and the radial depth of the positioning groove (21) are 1.5 to 2.5 mm.

7. The thermocouple sleeve annular welded structure according to claim 6, characterized in that: The wall thickness of the positioning ring (11) and the radial depth of the positioning groove (21) are 2 mm.

8. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: The inclination angles of the first inclined surface (12) and the second inclined surface (22) are 25° to 45°.

9. The thermocouple sleeve annular welded structure according to claim 8, characterized in that: The inclination angles of the first inclined surface (12) and the second inclined surface (22) are 30 degrees.

10. The thermocouple sleeve annular welded structure according to claim 1, characterized in that: The outer diameters of the first sleeve (1) and the second sleeve (2) are equal; and / or: the positioning ring (11), the first inclined surface (12), the positioning groove (21) and the second inclined surface (22) are milling structures.

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