A pre-fabricated thermal elbow assembly for a thermal pipe
By wrapping the outer wall of the insulated elbow with a prefabricated insulation layer and a curved, spliced outer protective shell, the problem of unstable on-site foaming quality of traditional insulated elbows is solved, achieving efficient and environmentally friendly insulation and shortening the construction cycle.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JILIN DONGSHENG TIANRUN TECH DEV CO LTD
- Filing Date
- 2025-08-25
- Publication Date
- 2026-06-09
AI Technical Summary
In traditional direct-buried insulated pipeline systems, insulated elbows cannot be prefabricated in the factory, and the quality of on-site foamed insulation is greatly affected by the environment and workers' skills. Uneven density and insufficient thickness can easily lead to cold bridges, resulting in long construction cycles and environmental pollution.
The prefabricated insulated pipe elbow assembly includes a prefabricated insulation layer and a bent pipe-shaped spliced outer protective shell wrapped and fixed on the outer wall of the insulated elbow. The prefabricated insulation layer is tightly attached to the outer wall of the insulated elbow, the edges of adjacent layers are tightly attached, and the splicing airtightness is improved by bolts, nuts and sealing rubber gaskets.
It achieves stable and controllable quality of the insulation layer, eliminates cold bridges, shortens the construction cycle, reduces pollution, lowers labor costs, and facilitates large-scale production and quality control.
Smart Images
Figure CN224339721U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of thermal insulation elbow technology, and in particular to a thermal insulation elbow assembly for prefabricated thermal insulation pipes. Background Technology
[0002] The descriptions in this section provide background information relating to this disclosure and do not constitute prior art.
[0003] In traditional direct-buried insulated pipeline systems, straight pipe sections typically use prefabricated insulated pipes from the factory. However, at locations where the pipeline needs to bend, due to the complex shape, it is usually impossible to prefabricate complete insulated elbows in the factory.
[0004] Existing practices and problems:
[0005] On-site foam insulation: At the construction site, uninsulated metal elbows are welded to straight pipes. Molds are then installed around the elbows, and polyurethane or other foaming materials are injected on-site to form an insulation layer. Finally, the outer protective layer is installed. Problems: Quality is greatly affected by the environment and worker skills; the insulation layer may have uneven density, insufficient thickness, or voids, easily leading to thermal bridging; the construction period is long; on-site foaming pollutes the environment. Utility Model Content
[0006] The purpose of this utility model is to provide an insulated elbow assembly for prefabricated insulated pipes. A prefabricated insulation layer and a bent-pipe-shaped spliced outer protective shell are wrapped and fixed to the outer wall of the insulated elbow. The prefabricated insulation layer is tightly fitted to the outer wall of the insulated elbow, and the edges of adjacent prefabricated insulation layers are tightly fitted together. This solves the technical problems of on-site foaming insulation technology, such as the quality being greatly affected by the environment and worker skills, uneven insulation layer density, insufficient thickness, or voids, which easily lead to cold bridges; long construction cycles; and on-site foaming polluting the environment.
[0007] This utility model provides an insulated elbow assembly for prefabricated insulated pipes, comprising:
[0008] Insulated elbow, with insulated straight pipes welded to both ends;
[0009] The outer wall of the heat-insulating elbow is fixedly fitted with a bent pipe-shaped spliced outer protective shell.
[0010] The inner walls of each part of the curved, spliced outer protective shell are glued and fixed with a pre-made insulation layer.
[0011] The inner wall shape of the prefabricated insulation layer, which is spliced into a bent tube shape, matches the outer contour of the insulation elbow.
[0012] The outer wall of the insulated straight pipe is fixedly fitted with an outer protective shell;
[0013] The two ends of the curved, spliced outer protective shell are welded to the ends of the outer protective shell on the same side.
[0014] As a further optimization, in order to splice the two pre-formed arc-shaped shells into a curved tube-shaped spliced outer protective shell, the curved tube-shaped spliced outer protective shell consists of two parts that are spliced and fixed at both ends.
[0015] As a further optimization, in order to splice the two prefabricated arc-shaped shells into a bent-tube spliced outer protective shell, the bent-tube spliced outer protective shell includes:
[0016] The first prefabricated arc-shaped shell is divided into two parts that are spliced together at the ends to form a tubular shape;
[0017] The first prefabricated arc-shaped shell has an integrally formed first connecting ear plate at the outer edge of its outer side;
[0018] The first connecting ear plate of the first prefabricated arc-shaped shell is attached to the first connecting ear plate at both ends;
[0019] The first connecting ear plate is fixedly connected with a first bolt and nut along its length.
[0020] As a further optimization, in order to splice the three pre-formed arc-shaped shells into a curved tube-shaped spliced outer protective shell, the curved tube-shaped spliced outer protective shell consists of three parts that are spliced and fixed at both ends.
[0021] As a further optimization, in order to splice the three prefabricated arc-shaped shells into a curved tubular spliced outer protective shell, the curved tubular spliced outer protective shell includes:
[0022] The second prefabricated arc-shaped shell is divided into three parts that are spliced together at both ends to form a tubular shape;
[0023] The second prefabricated arc-shaped shell has a second connecting ear plate integrally formed at the outer edge of its outer side;
[0024] The second connecting ear plate of the second prefabricated arc-shaped shell is fitted at both ends;
[0025] A second bolt and nut are fixedly connected to the second connecting ear plate along its length.
[0026] As a further optimization, to improve the airtightness of the joints of the curved tubular spliced outer protective shell, a sealing rubber gasket structure is installed at the joints of the curved tubular spliced outer protective shell, which includes:
[0027] The upper rubber pad and the lower rubber pad are respectively pasted and fixed to the two contact surfaces where the curved splicing outer protective shell is spliced;
[0028] The upper rubber pad and the lower rubber pad are attached to each other.
[0029] As a further optimization, to facilitate the splicing of the end of the insulation elbow with the straight insulation pipe on the same side, the two ends of the insulation elbow are coaxially and fixedly connected to a guide splicing pipe, which includes:
[0030] A cylindrical tube, which is coaxially fixedly connected to the end of the insulated elbow;
[0031] The outer end of the cylindrical tube is integrally formed with a tapered tube;
[0032] The tapered tube is inserted into the insulated straight tube on the same side.
[0033] As a further optimization, in order to facilitate quick docking and welding between the curved tubular spliced outer protective shell and the outer protective shell on the same side, an end interface welding structure is assembled between the end of the curved tubular spliced outer protective shell and the outer protective shell on the same side.
[0034] As a further optimization, to facilitate rapid docking and welding between the curved, spliced outer protective shell and the outer protective shell on the same side, the end interface welding structure includes:
[0035] The tapered connecting pipe is composed of tapered arc-shaped plates spliced together, with the larger end of the tapered connecting pipe facing outwards;
[0036] The number of the conical arc-shaped plates is the same as the number of the spliced parts of the curved tube-shaped spliced outer protective shell;
[0037] The conical arc plate is fixedly connected to the outer end of the splicing part corresponding to the curved splicing outer protective shell;
[0038] The cylindrical connecting pipe is composed of cylindrical arc-shaped plates spliced together.
[0039] The number of the cylindrical arc-shaped plates is the same as the number of the spliced parts of the curved tube-shaped spliced outer protective shell;
[0040] The cylindrical arc plate is integrally formed on the outer end of the corresponding conical arc plate;
[0041] The outer protective shell is inserted into the cylindrical connecting pipe on the same side;
[0042] The outer wall of the outer protective shell is welded to the inner wall of the cylindrical connecting pipe on the same side.
[0043] As a further optimization, in order to enhance the sealing of the weld between the end of the curved spliced outer protective shell and the outer protective shell on the same side, an annular solder layer is provided between the inner edge of the end face of the cylindrical connecting pipe and the outer wall of the outer protective shell on the same side.
[0044] This utility model provides an improved insulated elbow assembly for prefabricated insulated pipes, which has the following improvements and advantages compared with the prior art:
[0045] By wrapping and fixing a factory-prefabricated insulation layer and a curved, spliced outer protective shell around the outer wall of the insulated elbow, dependence on on-site construction environment and worker skills is eliminated, ensuring stable and controllable quality. The prefabricated insulation layer is tightly bonded to the outer wall of the insulated elbow, and the edges of adjacent prefabricated insulation layers are tightly bonded, effectively preventing cold bridges. The insulation efficiency is significantly higher than that of on-site foaming, reducing on-site foaming pollution. During construction, it is only necessary to weld the insulated elbow to the insulated straight pipe, then fasten the various parts of the curved, spliced outer protective shell with the prefabricated insulation layer attached to the inner wall to the outer wall of the insulated elbow and splice and fix them. Finally, weld the outer protective shell of the outer wall of the insulated straight pipe to the same side end of the curved, spliced outer protective shell. This shortens the construction cycle, reduces labor costs, has a high degree of standardization, and facilitates large-scale production and quality control. Attached Figure Description
[0046] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0047] Figure 1 This is a schematic diagram of the structure of this utility model;
[0048] Figure 2 This is a schematic diagram of the structure of a first embodiment of the curved tube splicing outer protective shell of this utility model;
[0049] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the tubular spliced outer protective shell of this utility model;
[0050] Figure 4 This is a schematic diagram of the guide splicing pipe structure of this utility model;
[0051] Figure 5 This is a schematic diagram of the end interface welding structure of this utility model.
[0052] Explanation of reference numerals in the attached figures:
[0053] 1-Insulated elbow, 2-Bent-pipe spliced outer protective shell, 21a-First prefabricated arc shell, 22a-First bolt and nut, 23a-First connecting lug, 21b-Second prefabricated arc shell, 22b-Second connecting lug, 23b-Second bolt and nut, 3-Guide splicing pipe, 31-Cylindrical pipe, 32-Conical pipe, 4-Insulated straight pipe, 5-End interface welding structure, 51-Conical connecting pipe, 52-Cylindrical connecting pipe, 6-Sealing rubber gasket structure, 61-Upper rubber gasket, 62-Lower rubber gasket, 7-Annular weld layer, 8-Outer protective shell. Detailed Implementation
[0054] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0055] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0056] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Example
[0057] Please see Figure 1 , Figure 2 , Figure 4 and Figure 5 This utility model provides a technical solution: a prefabricated insulated pipe insulated elbow assembly, comprising:
[0058] Insulated elbow 1, with insulated straight pipes 4 welded to both ends;
[0059] The outer wall of the thermal insulation elbow 1 is fixedly fitted with a bent pipe-shaped spliced outer protective shell 2;
[0060] The inner walls of each part of the curved, spliced outer protective shell 2 are glued and fixed with a pre-fabricated insulation layer;
[0061] The inner wall shape of the prefabricated insulation layer spliced into a bent tube shape matches the outer contour of the insulation elbow 1;
[0062] The outer wall of the insulated straight pipe 4 is fixedly fitted with an outer protective shell 8;
[0063] The two ends of the curved, spliced outer protective shell 2 are welded to the ends of the outer protective shell 8 on the same side.
[0064] Specifically in this embodiment, both the insulated elbow 1 and the insulated straight pipe 4 are existing technologies, and the connecting ends are welded.
[0065] The prefabricated insulation layer is prefabricated in the factory and is tightly bonded to the outer wall of the insulation elbow 1. The edges of adjacent prefabricated insulation layers are tightly bonded to effectively prevent cold bridges. The insulation efficiency is significantly higher than that of on-site foaming, reducing on-site foaming pollution.
[0066] Furthermore, the prefabricated insulation layer and the bent pipe spliced outer protective shell 2 are wrapped and fixed on the outer wall of the insulation elbow 1, eliminating the dependence on the on-site construction environment and worker skills, and ensuring stable and controllable quality.
[0067] More specifically, during construction, it is only necessary to weld the insulation elbow 1 to the insulation straight pipe 4, then fasten each part of the bent pipe spliced outer protective shell 2 with the pre-made insulation layer pasted on the inner wall to the outer wall of the insulation elbow 1 and splice and fix it, and finally weld the outer protective shell 8 of the outer wall of the insulation straight pipe 4 to the end of the bent pipe spliced outer protective shell 2 on the same side. This shortens the construction cycle, reduces labor costs, has a high degree of standardization, and is convenient for large-scale production and quality control.
[0068] It is understandable that the joints of the curved tubular spliced outer protective shell 2 are sealed and fitted; the end of the curved tubular spliced outer protective shell 2 is welded to the end of the outer protective shell 8 on the same side, and the quality of the circumferential weld is checked to avoid gaps, and the weld itself can achieve a sealing effect.
[0069] In some embodiments, the curved tubular spliced outer protective shell 2 consists of two parts that are spliced and fixed end to end; the curved tubular spliced outer protective shell 2 includes:
[0070] The first prefabricated arc-shaped shell 21a is divided into two parts that are spliced together at the ends to form a tubular shape;
[0071] The first connecting ear plate 23a is integrally formed at the outer edge of the first prefabricated arc-shaped shell 21a;
[0072] The first connecting ear plate 23a of the first prefabricated arc-shaped shell 21a is attached to the first prefabricated arc-shaped shell 21a at both ends;
[0073] The first connecting ear plate 23a is fixedly connected to the first bolt and nut 22a along the length direction.
[0074] Specifically, in this embodiment, the first prefabricated arc-shaped shell 21a is a prefabricated arc-shaped shell with a semi-circular cross-section;
[0075] Furthermore, the first connecting ear plates 23a that fit together with the first prefabricated arc-shaped shells 21a on the upper and lower sides are fixedly connected with the first bolts and nuts 22a along the length direction, thereby improving the strength of the splicing and fixing of the first prefabricated arc-shaped shells 21a on the upper and lower sides.
[0076] More specifically, the first bolt and nut 22a consists of multiple bolts and matching nuts. The first bolt and nut 22a are evenly distributed along the length of the first connecting ear plate 23a to ensure the stability of the splicing and fixing of the first prefabricated arc-shaped shell 21a on the upper and lower sides.
[0077] In some embodiments, the joint of the curved, spliced outer protective shell 2 is fitted with a sealing rubber gasket structure 6, which includes:
[0078] The upper rubber pad 61 and the lower rubber pad 62 are respectively pasted and fixed to the two contact surfaces at the joint of the curved splicing outer protective shell 2;
[0079] The upper rubber pad 61 and the lower rubber pad 62 are fitted together to improve the airtightness of the joint of the curved spliced outer protective shell 2, stabilize the heat preservation effect, and avoid the occurrence of cold bridge phenomenon.
[0080] In some embodiments, the two ends of the thermal insulation elbow 1 are coaxially and fixedly connected to a guide splicing pipe 3, which includes:
[0081] Cylindrical tube 31 is coaxially fixedly connected to the end of the heat-insulating elbow 1;
[0082] A tapered tube 32 is integrally formed on the outer end of the cylindrical tube 31;
[0083] The tapered tube 32 is inserted into the insulated straight tube 4 on the same side.
[0084] Specifically, in this embodiment, the outer diameter of the outer end of the tapered tube 32 is smaller than the inner diameter of the insulated straight tube 4, and the outer diameter of the cylindrical tube 31 is the same as the inner diameter of the insulated straight tube 4.
[0085] Furthermore, during the splicing process of the insulation elbow 1 and the insulation straight pipe 4 on the same side, the smaller end of the tapered pipe 32 is first inserted into the insulation straight pipe 4 on the same side for guidance, and finally the cylindrical pipe 31 is inserted into the insulation straight pipe 4 on the same side for positioning. This facilitates the splicing and positioning of the end of the insulation elbow 1 and the insulation straight pipe 4 on the same side, ensuring that there will be no misalignment problem when the two are welded.
[0086] In some embodiments, an end interface welding structure 5 is assembled between the end of the curved spliced outer protective shell 2 and the outer protective shell 8 on the same side;
[0087] The end interface welding structure 5 includes:
[0088] The tapered connecting pipe 51 is composed of tapered arc plates spliced together, and the larger end of the tapered connecting pipe 51 faces outward;
[0089] The number of conical arc plates is the same as the number of spliced parts of the curved tube spliced outer protective shell 2;
[0090] The conical arc plate is fixedly connected to the outer end of the splicing part of the corresponding curved splicing outer protective shell 2;
[0091] Cylindrical connecting pipe 52 is composed of cylindrical arc-shaped plates spliced together;
[0092] The number of cylindrical arc plates is the same as the number of spliced parts of the curved tube spliced outer protective shell 2;
[0093] The cylindrical arc plate is integrally formed on the outer end of the corresponding conical arc plate;
[0094] The outer protective shell 8 is inserted into the cylindrical connecting pipe 52 on the same side;
[0095] The outer wall of the outer protective shell 8 is welded to the inner wall of the cylindrical connecting pipe 52 on the same side.
[0096] Specifically, in this embodiment, the inner diameter of the cylindrical connecting pipe 52 is the same as the outer diameter of the outer protective shell 8;
[0097] Furthermore, the end of the outer protective shell 8 is inserted into the cylindrical connecting pipe 52 on the same side, which facilitates the quick docking and welding between the bent pipe spliced outer protective shell 2 and the outer protective shell 8 on the same side;
[0098] More specifically, the number of cylindrical arc plates and conical arc plates is the same as the number of splicing parts of the curved tube spliced outer protective shell 2, which means that the number of cylindrical arc plates and conical arc plates is the same as the number of splicing parts of the curved tube spliced outer protective shell 2.
[0099] It is understandable that when the outer wall of the end of the outer protective shell 8 is welded to the inner wall of the cylindrical connecting pipe 52 on the same side, the solder is filled into the gap between the outer wall of the end of the outer protective shell 8 and the inner wall of the cylindrical connecting pipe 52 on the same side.
[0100] In some embodiments, an annular solder layer 7 is provided between the inner edge of the end face of the cylindrical connecting pipe 52 and the outer wall of the outer protective shell 8 on the same side. The annular solder layer 7 is an additional welding layer that enhances the sealing of the weld between the end of the bent pipe spliced outer protective shell 2 and the outer protective shell 8 on the same side. Example
[0101] Please see Figure 3 The difference between this and Embodiment 1 is that the curved tube-shaped spliced outer protective shell 2 is composed of three parts that are spliced and fixed at both ends;
[0102] The curved, modular outer protective shell 2 includes:
[0103] The second prefabricated arc-shaped shell 21b is divided into three parts that are spliced together end to end into a tubular shape;
[0104] The second connecting ear plate 22b is integrally formed at the outer edge of the second prefabricated arc-shaped shell 21b;
[0105] The second connecting ear plate 22b of the second prefabricated arc-shaped shell 21b is attached to the first and last ends;
[0106] The second connecting ear plate 22b is fixedly connected to the second bolt and nut 23b along its length.
[0107] Specifically, in this embodiment, the second prefabricated arc-shaped shell 21b is a prefabricated arc-shaped shell with a circular arc cross-section;
[0108] Furthermore, the second connecting lugs 22b of the three second prefabricated arc-shaped shells 21b are fixedly connected with second bolts and nuts 23b along the length direction to improve the splicing and fixing strength of adjacent second prefabricated arc-shaped shells 21b;
[0109] More specifically, the second bolt and nut 23b consists of multiple bolts and matching nuts. The second bolt and nut 23b are evenly distributed along the length of the second connecting ear plate 22b to ensure the stability of the splicing and fixing of adjacent second prefabricated arc shells 21b.
[0110] Understandably, the three-part curved splicing outer protective shell, compared to the two-part design, has the advantages of smaller and lighter individual sections, making it easier to handle and position in confined spaces. The smaller sections reduce the difficulty and labor intensity of single-person operation, making it especially suitable for large-diameter elbows.
[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A prefabricated insulated pipe insulation elbow assembly, characterized in that, include: Insulated elbow (1), with insulated straight pipes (4) welded to both ends; The outer wall of the heat-insulating elbow (1) is fixedly sleeved with a bent pipe spliced outer protective shell (2). The inner walls of each part of the curved spliced outer protective shell (2) are glued and fixed with a pre-made heat insulation layer; The inner wall shape of the prefabricated insulation layer, which is spliced into a bent tube shape, matches the outer contour of the insulation elbow (1); The outer wall of the insulated straight pipe (4) is fixedly fitted with an outer protective shell (8); The two ends of the curved spliced outer protective shell (2) are welded to the ends of the outer protective shell (8) on the same side.
2. The prefabricated insulated pipe insulated elbow assembly according to claim 1, characterized in that, The curved tube-shaped spliced outer protective shell (2) consists of two parts that are spliced and fixed at both ends.
3. The prefabricated insulated pipe insulated elbow assembly according to claim 2, characterized in that, The curved, spliced outer protective shell (2) includes: The first prefabricated arc-shaped shell (21a) is divided into two parts that are spliced together at the ends to form a tubular shape; The first prefabricated arc-shaped shell (21a) has an integrally formed first connecting ear plate (23a) at the outer edge of its outer side. The first connecting ear plate (23a) is attached to the first prefabricated arc-shaped shell (21a) at both ends; The first connecting ear plate (23a) is fixedly connected to the first bolt and nut (22a) along the length direction.
4. The prefabricated insulated pipe insulated elbow assembly according to claim 1, characterized in that, The curved tube-shaped spliced outer protective shell (2) consists of three parts that are spliced and fixed at both ends.
5. The prefabricated insulated pipe insulated elbow assembly according to claim 4, characterized in that, The curved, spliced outer protective shell (2) includes: The second prefabricated arc-shaped shell (21b) is divided into three parts that are spliced together at the ends to form a tubular shape; The second prefabricated arc-shaped shell (21b) has a second connecting lug (22b) integrally formed at the outer edge of the side surface. The second connecting ear plate (22b) of the second prefabricated arc-shaped shell (21b) is attached to the second prefabricated arc-shaped shell (21b) at both ends; A second bolt and nut (23b) are fixedly connected to the second connecting ear plate (22b) along its length.
6. The prefabricated insulated pipe insulated elbow assembly according to claim 1, characterized in that, The curved, spliced outer protective shell (2) is fitted with a sealing rubber gasket structure (6) at the splice joint, which includes: The upper rubber pad (61) and the lower rubber pad (62) are respectively pasted and fixed to the two contact surfaces that are attached at the joint of the curved spliced outer protective shell (2); The upper rubber pad (61) and the lower rubber pad (62) are attached to each other.
7. The prefabricated insulated pipe insulated elbow assembly according to claim 1, characterized in that, The two ends of the thermal insulation elbow (1) are coaxially fixedly connected to a guide splicing pipe (3), which includes: A cylindrical tube (31) is coaxially fixedly connected to the end of the heat-insulating elbow (1); The outer end of the cylindrical tube (31) is integrally formed with a tapered tube (32). The tapered tube (32) is inserted into the insulated straight tube (4) on the same side.
8. The prefabricated insulated pipe insulated elbow assembly according to claim 1, characterized in that, The end of the curved spliced outer protective shell (2) is fitted with an end interface welding structure (5) between the end of the outer protective shell (8) on the same side.
9. A prefabricated insulated pipe insulated elbow assembly according to claim 8, characterized in that, The end interface welding structure (5) includes: The tapered connecting pipe (51) is composed of tapered arc plates spliced together, and the larger end of the tapered connecting pipe (51) faces outward; The number of the conical arc plates is the same as the number of spliced parts of the curved spliced outer protective shell (2); The conical arc plate is fixedly connected to the outer end of the splicing part corresponding to the curved splicing outer protective shell (2); Cylindrical connecting pipe (52) is composed of cylindrical arc-shaped plates spliced together; The number of the cylindrical arc plates is the same as the number of spliced parts of the curved spliced outer protective shell (2); The cylindrical arc plate is integrally formed on the outer end of the corresponding conical arc plate; The outer protective shell (8) is inserted into the cylindrical connecting pipe (52) on the same side; The outer wall of the outer protective shell (8) is welded to the inner wall of the cylindrical connecting pipe (52) on the same side.
10. A prefabricated insulated pipe insulated elbow assembly according to claim 9, characterized in that, An annular solder layer (7) is provided between the inner edge of the end face of the cylindrical connecting pipe (52) and the outer wall of the outer protective shell (8) on the same side.