A bellows compensation structure and a pipe system

Abstract

The application provides a bellows compensation structure and a pipeline system. The bellows compensation structure comprises a first connector pipe, a first port, a first connecting area on the outer wall of the first connector pipe extending from the first port in the direction away from the first port, a flow guide pipe comprising opposite second and third ports, the first port and the second port being fixedly connected, and the inner diameter of the flow guide pipe being equal to the inner diameter of the first connector pipe, a second connector pipe having a fourth port, the third port of the flow guide pipe extending into the second connector pipe through the fourth port, a bellows having a first end and a second end, the bellows being sleeved on the outer periphery of the flow guide pipe, the first end being fixedly connected with the first connector pipe at the first connecting area, and the second end being fixedly connected with the fourth port, the second connector pipe being capable of reciprocating relative to the flow guide pipe along the axial direction of the flow guide pipe through the bellows, and the wall thickness of the first connector pipe at the first connecting area being equal to the wall thickness of the flow guide pipe.

Description

Technical Field

[0001] This application relates to the field of pipeline technology, and in particular to a corrugated pipe compensation structure and pipeline system. Background Technology

[0002] In cryogenic or ultracryogenic pipeline systems, the drastic temperature changes of the medium (such as liquid oxygen, liquid nitrogen, LNG, etc.) can cause significant axial displacement due to thermal expansion and contraction. Without compensation, this can easily lead to stress concentration, support damage, or even pipeline rupture. Therefore, bellows compensation structures are commonly used to absorb displacement and alleviate thermal stress. Traditional compensators mainly consist of bellows, connecting pipes, and a flow guide. The bellows achieves displacement compensation through axial deformation, while the flow guide reduces fluid scouring and flow resistance on the bellows.

[0003] However, in existing technologies, the inner diameter is reduced during welding of the guide tube and the connecting pipe, forming a "neck." This increases flow resistance, easily causing turbulence and vibration, and may also lead to liquid accumulation or ice blockage at low temperatures. Furthermore, the weld area is prone to cracking under low-temperature conditions, affecting sealing performance and structural strength, and easily causing low-temperature, high-speed fluid to leak from the weld, accelerating fatigue damage. Utility Model Content

[0004] The purpose of this application is to provide a bellows compensation structure to improve the flow performance, stability and reliability of the bellows compensation structure in low-temperature environments.

[0005] To address the aforementioned technical problems, this application provides the following technical solutions:

[0006] This application provides a corrugated pipe compensation structure, comprising: a first connector having a first port, the outer wall of the first connector having a first mating region extending from the first port in a direction opposite to the first port; a guide pipe having opposing second and third ports, the first port and the second port being fixedly connected, and the inner diameter of the guide pipe being equal to the inner diameter of the first connector; a second connector having a fourth port, the third port of the guide pipe extending into the interior of the second connector through the fourth port; a corrugated pipe having a first end and a second end, the corrugated pipe being sleeved on the outer periphery of the guide pipe, the first end being located in the first mating region and fixedly connected to the outer wall of the first connector, the second end being fixedly connected to the fourth port, and the second connector being capable of reciprocating relative to the guide pipe along the axial direction of the guide pipe via the corrugated pipe; wherein, the wall thickness of the first connector located in the first mating region is equal to the wall thickness of the guide pipe.

[0007] In some embodiments of this application, the first connector is provided with a first docking structure on the side of the first docking area away from the first port, the first docking structure having a first docking surface, and the first end being fixedly connected to the first docking surface; the second connector is provided with a second docking structure at the fourth port, the second docking structure having a second docking surface, and the second end being fixedly connected to the second docking surface.

[0008] In some embodiments of this application, the corrugated pipe compensation structure further includes: a protective cylinder, which is sleeved on the outer periphery of the corrugated pipe, the protective cylinder having a third end and a fourth end, the third end being fixedly connected to the first docking structure, and the fourth end being clearance-fitted with the outer wall of the second connecting pipe.

[0009] In some embodiments of this application, the bellows compensation structure further includes: a limiting plate, which is annular and sleeved on the outer periphery of the second connecting pipe, and the limiting plate is clearance-fitted with the outer wall of the second connecting pipe, and the fourth end is connected to the second connecting pipe through the limiting plate.

[0010] In some embodiments of this application, the first docking structure is provided with a first docking groove on the side facing the second pipe, and the limiting plate is provided with a second docking groove on the side facing the first pipe; the third end of the protective cylinder is docked with the first docking groove, and the fourth end is docked with the second docking groove, so that the outer surfaces of the protective cylinder, the first docking structure, and the limiting plate form a smooth and continuous surface.

[0011] In some embodiments of this application, the protective cylinder, the guide pipe, the first docking structure, and the limiting plate enclose a receiving space, and the corrugated pipe and the second docking structure are disposed within the receiving space; the second docking structure includes a blocking surface disposed opposite to the second docking surface, the blocking surface being used to limit the displacement of the limiting plate.

[0012] In some embodiments of this application, the second connector includes a first part and a second part, wherein the inner diameter of the first part is larger than the outer diameter of the guide tube, the guide tube is disposed within the first part, and the inner diameter of the second part is equal to the inner diameter of the guide tube.

[0013] In some embodiments of this application, the first docking structure is provided with a first transition welding groove near the first docking surface, the first transition welding groove being used to reduce the thickness of the welding between the first docking structure and the corrugated pipe; the second docking structure is provided with a second transition welding groove near the second docking surface, the second transition welding groove being used to reduce the thickness of the welding between the second docking structure and the corrugated pipe; wherein, the corrugated pipe is a multi-layer structure.

[0014] In some embodiments of this application, the bellows compensation structure further includes a flexible layer disposed on the inner surface of the limiting plate facing the second connecting pipe.

[0015] This application also provides a piping system including the aforementioned corrugated pipe compensation structure.

[0016] Compared to existing technologies, the bellows compensation structure provided in this application achieves flush inner walls after connection by making the inner diameter of the guide pipe and the first connecting pipe equal. This effectively eliminates the "neck-in" phenomenon caused by welding in traditional structures, ensuring continuous flow channels and no abrupt changes in cross-section. This significantly reduces fluid resistance, thereby lowering the risk of columnar instability in the bellows. Simultaneously, the first mating area is located on the outer wall of the first connecting pipe, providing a reliable connection position for the bellows while avoiding the interior of the flow channel and preventing any impact on the smoothness of the inner wall. Furthermore, after the bellows is fitted and fixed to the first mating area, its body can cover the connection between the guide pipe and the first connecting pipe. This effectively prevents leakage of the cryogenic medium when microcracks or potential cracking risks appear in the weld area between the guide pipe and the first connecting pipe under cryogenic conditions, improving overall sealing safety and significantly enhancing the operational reliability and service life of the bellows compensation structure under harsh conditions such as cryogenics and high pressure. Attached Figure Description

[0017] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein:

[0018] Figure 1 A schematic diagram of the bellows compensation structure according to an embodiment of this application is shown.

[0019] Explanation of icon numbers:

[0020] 1. First connecting pipe; 101. First port; 102. First docking area; 103. First docking structure; 1031. First docking surface; 1032. First docking groove; 1033. First transition welding groove; 2. Guide pipe; 201. Second port; 202. Third port; 3. Second connecting pipe; 301. Fourth port; 302. Second docking structure; 3021. Second docking surface; 3022. Second docking groove; 3023. Second transition welding groove; 3024. Blocking surface; 4. Corrugated pipe; 5. Protective cylinder; 6. Limiting plate; 7. Flexible layer. Detailed Implementation

[0021] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0022] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains.

[0023] Example 1

[0024] This application provides a bellows compensation structure, such as Figure 1 As shown, the device includes a first connector 1 with a first port 101 and a first mating area 102 extending from the first port 101 in a direction away from the first port 101 on its outer wall; a guide tube 2 with a second port 201 and a third port 202 opposite to each other, the first port 101 and the second port 201 being fixedly connected, and the inner diameter of the guide tube 2 being equal to the inner diameter of the first connector 1; a second connector 3 with a fourth port 301, the third port 202 of the guide tube 2 extending into the interior of the second connector 3 through the fourth port 301; and a corrugated tube 4 with a first end and a second end, the corrugated tube 4 being sleeved on the outer periphery of the guide tube 2, the first end being located in the first mating area 102 and fixedly connected to the outer wall of the first connector 1, the second end being fixedly connected to the fourth port 301, and the second connector 3 being able to reciprocate relative to the guide tube 2 along the axial direction of the guide tube 2 through the corrugated tube 4.

[0025] The first connecting pipe 1 serves as the inlet end connection pipe, with a first port 101. Its outer wall extends from the first port 101 in a direction away from the port to form a first mating area 102, used for fixed connection with the first end of the corrugated pipe 4. The guide pipe 2 can be a hollow straight pipe structure, with a second port 201 and a third port 202 at its two ends, respectively. The inner diameter of the guide pipe 2 is equal to the inner diameter of the first connecting pipe 1, ensuring that the inner walls are flush during connection, forming a continuous, smooth, and stepless flow channel, avoiding abrupt changes in the flow cross-section or dead flow angles. The second connecting pipe 3 serves as the outlet end connection pipe, with a fourth port 301. The third port 202 of the guide pipe 2 extends into the interior of the second connecting pipe 3 through the fourth port 301. A clearance fit can be used to retain axial sliding space, allowing relative movement between the guide pipe 2 and the second connecting pipe 3, forming a through internal flow channel. The corrugated pipe 4 is sleeved on the outer periphery of the guide pipe 2, with its first end fixedly connected to the first mating area 102 of the first connecting pipe 1, so that the corrugated pipe 4 can cover the connection part between the guide pipe 2 and the first connecting pipe 1. The second end of the bellows 4 is fixedly connected to the fourth port 301 of the second pipe 3, thereby forming a complete flexible compensation unit. The connection method can be welding, riveting, threaded connection, etc.

[0026] When the pipeline expands and contracts due to temperature changes of the low-temperature medium, resulting in axial displacement, the guide pipe 2 and the first connecting pipe 1 together form a stable internal flow channel support. The second connecting pipe 3 can reciprocate relative to the guide pipe 2 through the axial expansion and contraction of the bellows 4, thereby effectively absorbing the axial displacement of the pipeline system caused by thermal expansion and contraction, while ensuring the continuity of the fluid channel and the reliability of the seal.

[0027] The bellows compensation structure provided in this application embodiment achieves flush inner walls after connection by making the inner diameters of the guide pipe 2 and the first connecting pipe 1 equal. This effectively eliminates the "neck-in" phenomenon caused by welding in traditional structures, ensuring continuous flow channels and no abrupt changes in cross-section. This significantly reduces fluid resistance, thereby lowering the risk of columnar instability in the bellows 4. Simultaneously, the first mating area 102 is located on the outer wall of the first connecting pipe 1, providing a reliable connection position for the bellows 4 while avoiding the interior of the flow channel and minimizing impact on the smoothness of the inner wall. Furthermore, after the bellows 4 is fitted and fixed to the first mating area 102, its body can cover the connection between the guide pipe 2 and the first connecting pipe 1. This effectively prevents leakage of the cryogenic medium when microcracks or potential cracking risks appear in the weld area between the guide pipe 2 and the first connecting pipe 1 under cryogenic conditions, improving overall sealing safety and significantly enhancing the operational reliability and service life of the bellows compensation structure under harsh conditions such as cryogenics and high pressure.

[0028] In some embodiments, the wall thickness of the first connector 1 in the first docking region 102 is equal to the wall thickness of the guide tube 2.

[0029] During the processing of the first connecting pipe 1, the wall thickness of the outer wall section corresponding to the first mating area 102 can be controlled to ensure that the wall thickness of this part is the same as that of the guide pipe 2. The second port 201 of the guide pipe 2 and the first port 101 of the first connecting pipe 1 can be connected by butt welding. Since the wall thicknesses of the two are the same, equal thickness butt welding can be achieved, the weld cross section is uniform, and there is no need to set up complex beveling transitions or additional reinforcement structures. After welding, the first end of the bellows 4 is sleeved on the first mating area 102 of the first connecting pipe 1 and circumferentially welded to the outer wall of the first connecting pipe 1 to achieve sealing and fixation.

[0030] Setting the wall thickness to be equal not only helps to achieve flush inner walls and optimize the flow field, but also ensures the continuity and smoothness of the outer wall. This allows the inner wall of the bellows 4 to fit tightly against the first docking area 102 and the outer circumferential surface of the guide pipe 2. When the pipeline system experiences thermal displacement, or when the bellows 4 undergoes axial compression or tensile deformation, its relative movement with the connection area of ​​the guide pipe 2 and the first connecting pipe 1 is smoother, avoiding mechanical interference caused by steps or misalignments. This effectively prevents local friction or wear of the bellows 4 during reciprocating movement, thereby improving the smoothness of the compensator's movement and its long-term durability.

[0031] In some embodiments, the first connector 1 is provided with a first docking structure 103 on the side of the first docking area 102 away from the first port 101. The first docking structure 103 has a first docking surface 1031 and a first end is fixedly connected to the first docking surface 1031. The second connector 3 is provided with a second docking structure 302 at the fourth port 301. The second docking structure 302 has a second docking surface 3021 and a second end is fixedly connected to the second docking surface 3021.

[0032] On the outer wall of the first connecting pipe 1, on the side of the first docking area 102 away from the first port 101, i.e., at the middle of the first connecting pipe 1, a first docking structure 103 is provided. The first docking structure 103 may be in the form of a radial protrusion, a flange ring, or a thickened welding platform, etc., and its end face forms a flat first docking surface 1031, making the first docking surface 1031 an annular end face perpendicular to the pipe axis, for sealing welding with the first end of the bellows 4.

[0033] At the fourth port 301 of the second pipe 3, a second mating structure 302 is provided, which may be a radial protrusion, an annular flange or a welding stop, and its end face forms a flat second mating surface 3021, so that the second mating surface 3021 can be an annular end face perpendicular to the pipe axis, for sealing welding with the second end of the bellows 4.

[0034] The bellows 4 is inserted into the guide tube 2, with its first end fitting against the first mating surface 1031, and a secure connection is achieved through circumferential welding. The second end extends to the fourth port 301 of the second connecting tube 3 and is fixed by circumferential welding to the second mating surface 3021. The circumferential welding of the two mating surfaces strengthens the constraint on both ends of the bellows 4, effectively limiting any lateral swaying or twisting that may occur under pressure or displacement, thereby enhancing the overall stability of the bellows 4 and reducing the risk of columnar instability.

[0035] In some embodiments, the corrugated pipe compensation structure further includes a protective cylinder 5, which is sleeved on the outer periphery of the corrugated pipe 4. The protective cylinder 5 has a third end and a fourth end. The third end is fixedly connected to the first docking structure 103, and the fourth end is in clearance fit with the outer wall of the second pipe 3.

[0036] The protective sleeve 5 can be a cylindrical metal component with an inner diameter larger than the outer diameter of the bellows 4, allowing it to be fitted around the outer circumference of the bellows 4. The protective sleeve 5 can have sufficient axial length to completely cover the bellows 4 body, providing external protection for the bellows 4.

[0037] The third end of the protective cylinder 5 is fixedly connected to the first mating surface 1031 or its adjacent area on the first mating structure 103, for example, by circumferential welding to achieve a sealed connection. The fourth end of the protective cylinder 5 extends toward the outer wall of the second connector 3 and maintains a certain radial and axial clearance with the outer wall of the second connector 3. This clearance can prevent the second connector 3 from interfering with the protective cylinder 5 when it drives the corrugated parts to move.

[0038] By setting up a protective sleeve 5 and fixing its third end to the first docking structure 103, and its fourth end to the outer wall of the second connecting pipe 3 with a clearance fit, effective physical protection and environmental isolation of the bellows 4 are achieved, while also taking into account the freedom of axial displacement of the second connecting pipe 3.

[0039] In some embodiments, the corrugated pipe compensation structure further includes: a limiting plate 6, which is annular and sleeved on the outer periphery of the second pipe 3, and the limiting plate 6 is in clearance fit with the outer wall of the second pipe 3, and the fourth end is connected to the second pipe 3 through the limiting plate 6.

[0040] The limiting plate 6 can be an annular metal plate or a short sleeve structure, with an inner diameter slightly larger than the outer diameter of the second connecting pipe 3, so that it can be fitted onto the outside of the second connecting pipe 3. The fourth end of the protective cylinder 5 does not directly contact the outer wall of the second connecting pipe 3, but extends to the limiting plate 6, and is fixedly connected to the limiting plate 6 by welding, bolting, or snap-fit ​​structures, so that the free end of the protective cylinder 5 is indirectly set on the second connecting pipe 3 through the limiting plate 6.

[0041] When the pipeline undergoes thermal expansion and contraction, the second connecting pipe 3 causes the second end of the bellows 4 to move. While a traditional clearance fit allows the second connecting pipe 3 to slide, it may cause the end of the protective cylinder 5, i.e., the fourth end, to become suspended, vibrate, or shift. By setting a limiting plate 6, effective axial and radial constraints can be provided on the protective cylinder 5 without restricting the axial displacement of the second connecting pipe 3. Especially under conditions with vibration loads, the limiting plate 6 can effectively suppress the resonance or swaying of the protective cylinder 5, preventing fatigue cracking or loosening of connections due to long-term vibration, thereby improving the stability of the overall structure.

[0042] In some embodiments, the first docking structure 103 is provided with a first docking groove 1032 on the side facing the second pipe 3, and the limiting plate 6 is provided with a second docking groove 3022 on the side facing the first pipe 1; the third end of the protective cylinder 5 is docked with the first docking groove 1032, and the fourth end is docked with the second docking groove 3022, so that the outer surfaces of the protective cylinder 5, the first docking structure 103, and the limiting plate 6 are smooth and continuous.

[0043] The first docking groove 1032 can be an annular groove on the end face of the first docking structure 103 facing the second connecting pipe 3, used to receive the third end of the protective cylinder 5. The second docking groove 3022 can be an annular groove on the end face of the limiting plate 6 facing the first connecting pipe 1, used to receive the fourth end of the protective cylinder 5. The cross-section of the annular groove can be rectangular, trapezoidal, etc., and its shape and size match the end of the protective cylinder 5. The two ends of the protective cylinder 5 can be processed into steps, chamfers, or embedded edges that are adapted to the corresponding docking grooves, facilitating precise positioning and tight fit.

[0044] After the protective cylinder 5 is fitted onto the outer periphery of the corrugated pipe 4, its third end is inserted into and embedded in the first docking groove 1032 on the first docking structure 103, and its fourth end is embedded in the second docking groove 3022 on the limiting plate 6. The docking parts can be fixedly connected by welding. After assembly, the protective cylinder 5, the first docking structure 103, and the limiting plate 6 form a continuous, smooth, and streamlined cylindrical surface, avoiding any external protrusions or recesses. The docking groove design allows the protective cylinder 5 to seamlessly connect with adjacent components, forming a unified outer contour that is not only aesthetically pleasing and neat but also eliminates stress concentration areas and reduces installation space.

[0045] In some embodiments, the protective cylinder 5, the guide pipe 2, the first docking structure 103, and the limiting plate 6 enclose a receiving space, and the corrugated pipe 4 and the second docking structure 302 are disposed within the receiving space; the second docking structure 302 includes a blocking surface 3024 disposed opposite to the second docking surface 3021, and the blocking surface 3024 is used to limit the displacement of the limiting plate 6.

[0046] The protective cylinder 5, the guide pipe 2, the first docking structure 103, and the limiting plate 6 together form a relatively enclosed accommodating space in the axial direction. The bellows 4 and the second docking structure 302 are both disposed within this accommodating space. The side of the second docking structure 302 facing the bellows 4 is the second docking surface 3021, and the side facing away from this surface forms the blocking surface 3024. The limiting plate 6 is fitted around the outer periphery of the second connecting pipe 3, and the second connecting pipe 3 can move axially relative to the limiting plate 6. When the second connecting pipe 3 drives the bellows 4 and the second docking structure 302 to move axially, the blocking surface 3024 can act as an axial stop structure to prevent the second connecting pipe 3 from moving excessively, which would cause the bellows 4 to be overstretched.

[0047] The corrugated pipe 4 is enclosed by the protective cylinder 5, the guide pipe 2, the first docking structure 103, and the limiting plate 6, effectively isolating it from external dust, rainwater, snow, and mechanical debris, preventing it from being scratched, flattened, or blocked, thus significantly improving operational safety and service life. The blocking surface 3024 on the second docking structure 302 acts as a rigid stop, effectively limiting the axial displacement range of the second connecting pipe 3 and preventing excessive stretching of the corrugated pipe 4, thereby further enhancing the operational stability and safety of the compensation structure under complex working conditions.

[0048] In some embodiments, the second connector 3 includes a first part and a second part, the inner diameter of the first part is larger than the outer diameter of the guide tube 2, the guide tube 2 is disposed in the first part, and the inner diameter of the second part is equal to the inner diameter of the guide tube 2.

[0049] The second connector 3 is a stepped reducing pipe structure, divided into a first part and a second part along the axial direction. The first part is located on the side closer to the bellows 4, and its inner diameter is larger, forming an expanded cavity to accommodate the third port 202 of the guide pipe 2. A certain annular gap can be maintained between the outer wall of the guide pipe 2 and the inner wall of the first part, allowing axial relative movement between the guide pipe 2 and the second connector 3. The second part is located on the side farther from the bellows 4, and its inner diameter is the same as that of the guide pipe 2, forming a constant-diameter connection section that matches the downstream pipeline, ensuring a smooth transition of the flow channel.

[0050] By making the inner diameter of the second part of the second connector 3 equal to the inner diameter of the guide pipe 2, the continuous equal diameter of the outlet flow channel is ensured, avoiding necking or steps and effectively reducing fluid resistance, thereby reducing the risk of columnar instability of the bellows 4. At the same time, the second part can also serve as a mechanical limiting structure, blocking the guide pipe 2 during the compression of the bellows 4, preventing the second connector 3 from excessively shrinking inward toward the bellows 4, and avoiding instability, local buckling, or damage to the bellows 4 due to excessive compression, thereby further improving the safety and reliability of the bellows compensation structure operation.

[0051] In some embodiments, the first docking structure 103 is provided with a first transition welding groove 1033 near the first docking surface 1031, and the first transition welding groove 1033 is used to reduce the thickness of the welding between the first docking structure 103 and the corrugated pipe 4; the second docking structure 302 is provided with a second transition welding groove 3023 near the second docking surface 3021, and the second transition welding groove 3023 is used to reduce the thickness of the welding between the second docking structure 302 and the corrugated pipe 4; wherein, the corrugated pipe 4 is a multi-layer structure.

[0052] The first transition welding groove 1033 may be an annular groove disposed on the outer periphery of the first mating structure 103 near the first mating surface 1031, and the cross-section of the groove may be rectangular, U-shaped or V-shaped. The second transition welding groove 3023 is disposed at a corresponding position on the second mating structure 302 near the second mating surface 3021, and the structure may be symmetrical or identical to the first transition welding groove 1033.

[0053] By setting the first transition welding groove 1033 and the second transition welding groove 3023, the thickness of the welding position between the first mating structure 103 and the second mating structure 302 and the bellows 4 can be reduced. When the first end of the bellows 4 is fitted onto the first mating structure 103, aligning its end with the first mating surface 1031, the second end of the bellows 4 is similarly aligned with the second mating surface 3021. Circumferential welding is performed at the first transition welding groove 1033 and the second transition welding groove 3023. Since the wall thickness has been reduced at this point, it matches well with the thickness of the bellows 4, achieving equal or near-equal thickness welding. This solves the problem that welding between thin-walled and thick-walled parts is prone to excessive current causing the thin-walled part to burn through, while insufficient current prevents welding.

[0054] The corrugated pipe 4 can adopt a multi-layer structure, that is, it is composed of two or more concentric corrugated pipes 4 stacked together, and the layers can be tightly fitted or have a small gap. Each layer of corrugated pipe 4 can be made of stainless steel material (such as 304, 316L) with good formability and low temperature toughness, and is assembled by sequentially nesting after being processed by hydroforming or roll forming process.

[0055] By using multiple layers of metal walls to jointly bear the internal pressure, the pressure resistance of the bellows 4 is significantly improved. Compared with a single-layer structure, a higher pressure rating can be achieved without increasing the wall thickness. At the same time, the multi-layer thin walls can maintain low stiffness while ensuring high welding strength and high sealing performance, which is beneficial for achieving large axial or lateral displacement compensation within a limited installation space.

[0056] In some embodiments, the bellows compensation structure further includes a flexible layer 7, which is disposed on the inner surface of the limiting plate 6 facing the second connecting pipe 3.

[0057] The flexible layer 7 can be a brush layer, foam layer, etc., and is disposed on the inner circumferential surface of the limiting plate 6, that is, the side facing the outer wall of the second connecting pipe 3. The limiting plate 6 is sleeved on the outer circumference of the second connecting pipe 3, maintaining an axial sliding fit with it. The flexible layer 7 is located between the limiting plate 6 and the second connecting pipe 3. When the two undergo relative movement or slight contact, the flexible layer 7 can act as an intermediate medium to buffer and protect. The flexible layer 7 can adopt a continuous sealing structure, which can form a seal between the limiting plate 6 and the second connecting pipe 3, preventing external dust, moisture or corrosive media from entering the accommodating space, further protecting the internal bellows 4.

[0058] By incorporating the flexible layer 7, direct metal-to-metal contact between the limiting plate 6 and the outer wall of the second connecting pipe 3 is avoided, significantly reducing frictional resistance during relative sliding or vibration. Especially in cases of installation deviation or deformation leading to eccentricity, the flexible layer 7 can adapt to minor misalignments through elastic deformation, ensuring that the limiting plate 6 does not jam or wear unevenly during sliding, thus guaranteeing the reliability of the compensation structure.

[0059] Example 2

[0060] This application provides a pipeline system including the corrugated pipe compensation structure provided in Embodiment 1.

[0061] In pipeline systems, bellows compensation structures can be installed at appropriate locations based on calculations of thermal expansion and contraction displacement and stress analysis results. The first connector 1 of the bellows compensation structure can be welded or flanged to the upstream pipeline, and the second connector 3 can be connected to the downstream pipeline. This allows the entire bellows compensation structure to be connected in series in pipelines transporting cryogenic or variable-temperature media, such as cryogenic pipeline systems for liquid oxygen, liquid nitrogen, LNG, and cryogenic ethylene. When the pipeline system experiences significant axial displacement due to drastic temperature changes during operation, the bellows 4 can absorb the displacement through compression or tensile deformation, preventing stress concentration on the pipeline body or supporting structure.

[0062] The pipeline system provided in this application, by integrating the corrugated pipe compensation structure of Embodiment 1, not only achieves effective compensation for thermal expansion and contraction displacement, but also fundamentally solves the problems of high flow resistance, easy vibration, easy erosion, and easy leakage of traditional compensators. Therefore, the pipeline system has advantages such as low flow resistance, high stability, long service life, and high safety, and is particularly suitable for low-temperature and high-pressure industrial scenarios with extremely high operational reliability requirements, demonstrating significant technological advancements and broad engineering application value.

[0063] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A bellows compensation structure, characterized in that, include: The first connector has a first port, and the outer wall of the first connector has a first docking area extending from the first port in a direction away from the first port. The guide tube includes a second port and a third port opposite to each other, the first port and the second port are fixedly connected, and the inner diameter of the guide tube is equal to the inner diameter of the first connecting pipe; The second connector has a fourth port, through which the third port of the guide tube extends into the interior of the second connector; A corrugated pipe has a first end and a second end. The corrugated pipe is sleeved on the outer periphery of the guide pipe. The first end is located in the first docking area and is fixedly connected to the outer wall of the first connector. The second end is fixedly connected to the fourth port. The second connector can reciprocate along the axial direction of the guide pipe relative to the guide pipe through the corrugated pipe. Wherein, the wall thickness of the first connector located in the first docking area is equal to the wall thickness of the guide pipe.

2. The bellows compensation structure according to claim 1, characterized in that, The first connector is provided with a first docking structure on the side of the first docking area away from the first port. The first docking structure has a first docking surface, and the first end is fixedly connected to the first docking surface. The second connector is provided with a second docking structure at the fourth port. The second docking structure has a second docking surface, and the second end is fixedly connected to the second docking surface.

3. The bellows compensation structure according to claim 2, characterized in that, Also includes: A protective sleeve is fitted around the outer periphery of the corrugated pipe. The protective sleeve has a third end and a fourth end. The third end is fixedly connected to the first docking structure, and the fourth end is clearance-fitted with the outer wall of the second connecting pipe.

4. The bellows compensation structure according to claim 3, characterized in that, Also includes: A limiting plate, which is annular, is sleeved on the outer periphery of the second connecting pipe, and the limiting plate is clearance-fitted with the outer wall of the second connecting pipe. The fourth end is connected to the second connecting pipe through the limiting plate.

5. The bellows compensation structure according to claim 4, characterized in that, The first docking structure has a first docking groove on the side facing the second pipe, and the limiting plate has a second docking groove on the side facing the first pipe. The third end of the protective cylinder is connected to the first docking groove, and the fourth end is connected to the second docking groove, so that the outer surface of the protective cylinder, the first docking structure, and the limiting plate are smooth and continuous.

6. The bellows compensation structure according to claim 4, characterized in that, The protective cylinder, the guide pipe, the first docking structure, and the limiting plate enclose a receiving space, and the corrugated pipe and the second docking structure are disposed within the receiving space; The second docking structure includes a blocking surface disposed opposite to the second docking surface, the blocking surface being used to limit the displacement of the limiting plate.

7. The bellows compensation structure according to claim 6, characterized in that, The second connector includes a first part and a second part. The inner diameter of the first part is larger than the outer diameter of the guide tube. The guide tube is disposed inside the first part. The inner diameter of the second part is equal to the inner diameter of the guide tube.

8. The bellows compensation structure according to claim 2, characterized in that, The first docking structure is provided with a first transition welding groove near the first docking surface. The first transition welding groove is used to reduce the thickness of the welding between the first docking structure and the corrugated pipe. The second docking structure is provided with a second transition welding groove near the second docking surface. The second transition welding groove is used to reduce the thickness of the welding between the second docking structure and the bellows. The corrugated pipe has a multi-layer structure.

9. The bellows compensation structure according to claim 5, characterized in that, Also includes: A flexible layer is disposed on the inner surface of the limiting plate facing the second connecting pipe.

10. A piping system, characterized in that, Includes the bellows compensation structure according to any one of claims 1 to 9.

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