Composite pipe head welding structure capable of guaranteeing welding strength of base body

Abstract

The utility model relates to the technical field of petrochemical equipment, in particular to a composite tube head welding structure capable of guaranteeing welding strength of a base body, which comprises a composite tube plate and a plurality of composite heat exchange tubes, and the composite tube plate comprises a tube plate base body and a tube plate composite layer covering the outer side face of the tube plate base body. The composite heat exchange tube comprises a tube base body and a tube composite layer, and the tube composite layer is arranged on the inner side face of the tube base body in a penetrating and covering mode. The ends of the composite heat exchange tubes are flush with the outer side face of the tube plate base body. A groove is formed in a pipe hole of the pipe plate base body, a welding groove is defined by the groove and the outer wall of the pipe base body, an inner welding layer is welded to the welding groove, an outer welding layer is arranged between the pipe hole of the pipe plate composite layer and a port of the pipe composite layer, and the outer welding layer wraps the inner welding layer. Compared with the prior art, the tube plate and the heat exchange tube are each of a composite structure, during welding, the tube plate base body and the tube base body are welded and fixed firstly, then the tube plate composite layer and the tube composite layer are welded and fixed, and therefore it can be guaranteed that welding and connecting strength exists between the tube plate base body and the tube base body.

Description

TECHNICAL FIELD

[0001] The utility model relates to petrochemical equipment technical field, concretely relates to a kind of composite pipe head welding structure of guaranteeing base body welding strength. BACKGROUND

[0002] In petrochemical equipment, tube type heat exchanger is an important equipment, and the welding joint of tube sheet and heat exchange tube is the most important and the most vulnerable welding joint in the equipment, and its quality directly affects the service life of the equipment and the stability of the device. The connection between the heat exchange tube and the tube sheet is the main part of the product failure, and its reliability directly affects the service life of the product. The most common way to connect the heat exchange tube and the tube sheet is welding, which is commonly known as tube-tube sheet welding. In the production and manufacturing process of shell-and-tube heat exchanger, tube-tube sheet welding is the most critical process.

[0003] The traditional heat exchange tube and tube sheet welding method generally passes the heat exchange tube through the tube sheet, and then opens a groove on the tube sheet, and then welds the two together. For example, the Chinese patent document CN102151958A discloses a welding method for the welding joint of heat exchanger tube sheet and heat exchange tube. In the assembly of heat exchange tube and tube sheet, a structure with a recess of 0.5-1mm on the surface of the tube sheet is adopted. In this way, the tungsten electrode can easily penetrate into the root of the heat exchange tube and tube sheet during welding, and the electric arc can reach the sharp corner position during self-fusion welding. Later, the applicant developed a heat exchanger tube head structure disclosed in the Chinese patent document CN218455401U to ensure root penetration, which includes a tube sheet and a heat exchange tube. The tube sheet has a tube hole, and the end of the heat exchange tube penetrates into the tube hole, and the end of the heat exchange tube is recessed into the surface of the tube sheet with a height of 0.5-1mm. The end of the tube hole is provided with a welding groove in the form of an inverted conical frustum, and the angle of the welding groove is 35°-50°, and the height of the welding groove is 1.5-2.5mm. As an improvement, the bottom of the welding groove is provided with a horizontally arranged annular step around the tube hole periphery, and the transition between the annular step and the side wall of the welding groove is provided with a concave round corner. Since the step is provided at the bottom of the welding groove, the bottom of the groove is widened, the difficulty of the root of the fusion groove is reduced, and the qualified rate is improved. Furthermore, the concave round corner between the annular step and the welding groove makes the transition smoother, and the root position is easier to reach by fillet welding, ensuring root penetration.

[0004] The tube plate and the heat exchange tube are both single-layer structures, while for the composite tube plate and the composite heat exchange tube, the composite tube plate comprises a tube plate base and a tube plate composite layer covering the outer surface of the tube plate base, and the composite heat exchange tube comprises a tube base and a tube composite layer covering the inner surface of the tube base, the tube plate base and the tube base are generally made of high-temperature and high-strength metal, and the tube plate composite layer and the tube composite layer need to withstand the erosion of the medium and are generally made of corrosion-resistant and high-temperature-resistant metal. However, the existing welding method is relatively rough, and the base layer and the composite layer are not distinguished, and the traditional single-layer tube head welding method is adopted, that is, the tube head is welded and fixed. However, the inventors found that since the base layer is located inside the composite layer, the base layer and the base layer are not fully welded during welding, or the base layer and the composite layer are welded with different materials, which makes the welding strength between the tube plate base and the tube base as the main body insufficient. Furthermore, the existing technology has a heat exchange tube penetrating out of the tube plate, and after assembly, the tube plate base is completely hidden inside, and only the tube plate composite layer and the tube composite layer / tube base can be welded, and the strength of the tube head formed by welding needs to be strengthened. SUMMARY

[0005] In view of all or part of the above technical problems existing in the prior art, the utility model provides a composite tube head welding structure guaranteeing base welding strength.

[0006] In order to achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] The utility model provides a composite tube head welding structure guaranteeing base welding strength, including composite tube plate and multiple composite heat exchange tubes, the composite tube plate includes tube plate base and tube plate composite layer covering the outer side surface of tube plate base, the composite heat exchange tube includes tube base and tube composite layer, the tube composite layer is equipped with covering the inner side surface of tube base,

[0008] The composite tube plate is provided with multiple tube holes for the multiple composite heat exchange tubes to correspondingly penetrate, and the end of the composite heat exchange tube is flush with the outer side surface of the tube plate base.

[0009] The port of the tube hole of the tube plate base is provided with a groove, the groove and the outer wall of the tube base form a welding groove, the welding groove is provided with an inner welding layer, and the outer welding layer is arranged between the tube hole of the tube plate composite layer and the port of the tube composite layer, and the outer welding layer wraps the inner welding layer.

[0010] Specifically, the hole diameter of the tube hole of the tube plate composite layer is greater than the hole diameter of the tube hole of the tube plate base, so as to form an annular groove with an L-shaped cross section between the outer side surface of the tube plate base and the hole wall of the tube hole of the tube plate composite layer, and the outer welding layer is also filled in the annular groove.

[0011] Specifically, part of the inner welding layer is filled between the welding groove and the outer wall of the tube base, and part of the inner welding layer is filled between the outer side surface of the tube plate base and the end surface of the tube base.

[0012] Specifically, the tube plate base body and the tube plate cladding are dissimilar metal bodies, the tube base body and the tube cladding are dissimilar metal bodies; and / or: the tube plate base body, the tube base body and the inner welding layer are the same metal body, the tube plate cladding, the tube cladding and the outer welding layer are the same metal body.

[0013] Specifically, the cross section of the bevel is a quarter of a circular arc.

[0014] Specifically, the outer surface of the outer welding layer is polished into a smooth streamline shape.

[0015] Specifically, the outer welding layer is flush with the outer side of the tube plate cladding and the inner surface of the tube cladding.

[0016] Specifically, the inner welding layer and / or the outer welding layer is a spiral solder structure.

[0017] Specifically, the inner welding layer and / or the outer welding layer is a single-layer annular structure or a multi-layer annular structure.

[0018] Specifically, the thickness of the tube plate cladding is less than the thickness of the tube plate base body, and the thickness of the tube cladding is less than the thickness of the tube base body.

[0019] The beneficial effects of the utility model are:

[0020] The utility model discloses a kind of composite pipe head welding structures of guaranteeing base body welding strength, compared with prior art, tube plate and heat exchange pipe are composite double-layer structure, when welding, first the annular gap between tube plate base body and tube base body is welded and fixed, then tube plate cladding and tube cladding are welded and fixed, so it can ensure that there is implementation welding and connecting strength between tube plate base body and tube base body. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is the structure schematic view of composite tube plate and composite heat exchange pipe in embodiment, in alignment assembly after welding state

[0022] Figure 2 It is the structure schematic view of a kind of composite pipe head welding structures of guaranteeing base body welding strength in embodiment.

[0023] Figure 3 It is the structure schematic view of a kind of composite pipe head welding structures of guaranteeing base body welding strength in another embodiment.

[0024] REFERENCE NUMERALS:

[0025] Composite tube plate 1, tube plate base body 11, tube plate cladding 12, tube hole 13;

[0026] Composite heat exchange pipe 2, tube base body 21, tube cladding 22;

[0027] Inner welding layer 3, outer welding layer 4, annular material groove 5, bevel 6, welding groove 7. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the utility model will be clearly and completely described in connection with the drawings of the embodiments of the utility model. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

[0029] The composite pipe head welding structure for guaranteeing the welding strength of the base body in this embodiment, as shown in the figure, comprises a composite pipe plate 1 and a plurality of composite heat exchange pipes 2 (only schematically shown in part in the figure), and the composite pipe plate 1 comprises a pipe plate base body 11 and a pipe plate composite layer 12 covering the outer side surface of the pipe plate base body 11. Each of the composite heat exchange pipes 2 comprises a pipe base body 21 and a pipe composite layer 22 covering the inner side surface of the pipe base body 21. Figures 1 to 2

[0030] The composite pipe plate 1 is provided with a plurality of pipe holes 13 for the plurality of composite heat exchange pipes 2 to be correspondingly arranged, and the end portions of the composite heat exchange pipes 2 are flush with the outer side surface of the pipe plate base body 11.

[0031] The port of the pipe hole of the pipe plate base body 11 is provided with a groove 6, and the cross section of the groove 6 is in the shape of one fourth of a circular arc, which can be actually changed into the shape of a truncated cone. The groove 6 and the outer wall of the pipe base body 21 enclose a welding groove 7, and the annular gap between the welding groove 7 and the outer wall of the pipe base body 21 is welded and fixed first, so that the welding groove 7 is filled with the inner welding layer 3, and the welding and connecting strength between the pipe plate base body 11 and the pipe base body 21 is ensured. Then, the pipe plate composite layer 12 and the pipe composite layer 22 are welded and fixed, so that the pipe hole 13 of the pipe plate composite layer 12 and the port between the pipe composite layer 22 are provided with the outer welding layer 4, and the outer welding layer 4 wraps the inner welding layer 3. Of course, on the basis of ensuring the welding structure between the pipe plate base body 11 and the pipe base body 21 and between the pipe plate composite layer 12 and the pipe composite layer 22, the pipe plate base body 11 and the pipe composite layer 22 and the pipe plate composite layer 12 and the pipe base body 21 can also be welded, so that the welding layer is more compact. As shown in the figure, the inner welding layer 3 exactly fills the welding groove 7, and only the groove wall of the welding groove 7 and the pipe base body 21 are welded, and the inner wall of the pipe hole of the pipe plate composite layer 12 and the port between the pipe base body 21 and the pipe composite layer 22 are covered and welded by the composite filler layer 4. Another embodiment is shown in the figure, after the welding groove 7 is filled with the inner welding layer 3, one more layer of the inner welding layer 3 is continuously welded, the outer side surface of the pipe plate base body 11 and the port of the pipe base body 21 are both covered and welded, and then the composite filler layer 4 is welded, that is, part of the inner welding layer 3 is filled between the welding groove 7 and the outer wall of the pipe base body 21, and part of the inner welding layer 3 is filled between the outer side surface of the pipe plate base body 11 and the end surface of the pipe base body 21. Figure 2 Figure 3

[0032] ​​​In this embodiment, the pipe hole 13 of the tube plate complex layer 12 has a larger diameter than the pipe hole 13 of the tube plate base body 11, so that an annular groove 5 with an L-shaped cross section is formed between the outer side of the tube plate base body 11 and the hole wall of the pipe hole 13 of the tube plate complex layer 12, and the outer welding layer 4 is also filled in the annular groove 5.

[0033] In practice, the tube plate base body 11 and the tube plate complex layer 12 are dissimilar metal bodies, and the tube base body 21 and the tube complex layer 22 are dissimilar metal bodies; and / or: the tube plate base body 11, the tube base body 21 and the inner welding layer 3 are similar metal bodies, and the tube plate complex layer 12, the tube complex layer 22 and the outer welding layer 4 are similar metal bodies. In general, the base body is the main part, which adopts high-temperature-resistant and high-strength metal, while the tube plate complex layer 12, the outer welding layer and the tube complex layer 22 need to withstand the erosion of the medium, and generally adopt corrosion-resistant and high-temperature-resistant metal.

[0034] Specifically, the outer surface of the outer welding layer 4 is polished into a smooth streamline shape, and the surface is polished to form a smooth streamline shape after welding, without obvious corners, so as to reduce erosion wear. Similarly, the outer welding layer 4 is flushly connected to the outer side of the tube plate complex layer 12 and the inner surface of the tube complex layer 22.

[0035] Specifically, the inner welding layer 3 and / or the outer welding layer 4 are spiral solder structures, and are welded around the annular seam between the port of the pipe hole 13 of the tube plate base body 11 and the port of the tube base body 21, and between the pipe hole 13 of the tube plate complex layer 12 and the port of the tube complex layer 22. Moreover, the inner welding layer 3 and the outer welding layer 4 are multi-layer annular structures through multiple turns of welding. Of course, in practice, it can be changed to a single-layer annular structure, that is, one turn of welding is completed.

[0036] Specifically, the thickness of the tube plate complex layer 12 is smaller than the thickness of the tube plate base body 11, and the thickness of the tube complex layer 22 is smaller than the thickness of the tube base body 21.

[0037] In the description of the utility model, obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. The components of the utility model embodiments described and shown in the drawings can be arranged and designed in various different configurations.

[0038] Therefore, the above detailed description of the embodiments of the utility model provided in the drawings is not intended to limit the scope of the claimed utility model, but only represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the utility model.

[0039] In the description of the utility model, it is necessary to explain that the terms "middle", "upper", "lower", "horizontal", "inner", "outer" and the like indicate the position or location relationship based on the position or location relationship shown in the drawings, or the position or location relationship of the product of the application when it is usually placed, and are only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element indicated must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the utility model. In addition, the terms "first", "second" and the like are only used for differentiation in description and cannot be understood as indicating or implying relative importance.

[0040] In the description of the utility model, it is necessary to explain that the terms "setting", "connection", "connection" should be understood broadly unless otherwise specified and limited, for example, it can be fixedly connected, can be detachably connected, or integrally connected. It can be mechanically connected or electrically connected. It can be directly connected or indirectly connected through an intermediate medium. It can be the communication between two elements. For ordinary skilled persons in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

Claims

1. A composite pipe head welding structure that ensures the welding strength of the base body, characterized by: The composite tube sheet (1) comprises a composite tube sheet (1) and a plurality of composite heat exchange tubes (2), wherein the composite tube sheet (1) comprises a tube sheet base (11) and a tube sheet cladding (12) covering the outer side of the tube sheet base (11); the composite heat exchange tube (2) comprises a tube base (21) and a tube cladding (22), and the tube cladding (22) is provided through and covers the inner side of the tube base (21); The composite tube sheet (1) is provided with a plurality of tube holes (13) for a plurality of composite heat exchange tubes (2) to pass through in a one-to-one correspondence, and the ends of the composite heat exchange tubes (2) are flush with the outer side surface of the tube sheet base (11); The end of the tube hole of the tube sheet base (11) is provided with a groove (6), the groove (6) and the outer wall of the tube base (21) form a welding groove (7), the welding groove (7) is welded with an inner welding layer (3), and an outer welding layer (4) is provided between the tube hole (13) of the tube sheet cladding (12) and the end of the tube cladding (22), and the outer welding layer (4) wraps the inner welding layer (3).

2. A composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The diameter of the tube hole (13) of the tube sheet cladding (12) is larger than the diameter of the tube hole (13) of the tube sheet base (11), thereby forming an annular groove (5) with an L-shaped cross section between the outer side surface of the tube sheet base (11) and the hole wall of the tube hole (13) of the tube sheet cladding (12), and the outer welding layer (4) is also filled in the annular groove (5).

3. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: Part of the inner welding layer (3) is filled between the welding groove (7) and the outer wall of the tube base (21), and part of the inner welding layer (3) is filled between the outer side surface of the tube plate base (11) and the end surface of the tube base (21).

4. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The tube sheet base (11) and the tube sheet cladding (12) are made of different metals, and the tube base (21) and the tube cladding (22) are made of different metals; and / or the tube sheet base (11), the tube base (21) and the inner welding layer (3) are made of the same metal, and the tube sheet cladding (12), the tube cladding (22) and the outer welding layer (4) are made of the same metal.

5. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The cross section of the groove (6) is in the shape of a quarter of a circular arc.

6. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The outer surface of the outer welding layer (4) is polished into a smooth streamline shape.

7. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The outer welding layer (4) is flush with the outer side surface of the tube sheet cladding (12) and the inner surface of the tube cladding (22).

8. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The inner solder layer (3) and / or the outer solder layer (4) is a spiral solder structure.

9. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The inner welding layer (3) and / or the outer welding layer (4) is a single-layer annular structure or a multi-layer annular structure.

10. The composite pipe head welding structure for ensuring base welding strength according to claim 1, characterized in that: The thickness of the tube sheet cladding (12) is smaller than the thickness of the tube sheet base (11), and the thickness of the tube cladding (22) is smaller than the thickness of the tube base (21).

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