Zero-thermal-bridge external sliding waterproof directly-buried steam heat preservation pipeline and method

Abstract

The invention discloses a zero-heat-bridge external sliding waterproof directly-buried steam heat preservation pipeline and a method, and belongs to the technical field of steam heat preservation pipelines. A heat preservation cushion layer, an inorganic hard heat preservation layer, a sealing heat preservation layer and a heat preservation outer protection layer are sequentially laid on the outer wall of the working pipe from inside to outside. And a plurality of groups of inner guide supports which are uniformly distributed along the circumferential direction of the longitudinal section of the pipeline are arranged between the outer sleeve and the heat-insulating outer protective layer. The inner side of a fixing sleeve in the inner guide support is fixedly connected with the heat preservation outer protection layer through a plurality of fixing pieces. The base plate is coaxially fixed on the outer side of the fixing sleeve; the first sliding block is fixed outside the base plate, and the second sliding block is fixed inside the outer sleeve; the arc length of the second sliding block is greater than that of the first sliding block; a running gap exists between the first sliding block and the second sliding block, and when the working pipe generates thermal expansion deformation, the first sliding block and the second sliding block are in sliding fit. According to the pipeline, axial staggered sliding between the working pipe and the outer sleeve can be achieved, the heat preservation and insulation effects of the pipeline are enhanced, and effective water prevention is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of steam insulation pipes, and in particular relates to a zero-thermal-bridge external sliding waterproof direct-buried steam insulation pipe and a method. Background Art

[0002] Direct buried steam insulation pipe refers to steam insulation pipe laid underground, and its typical structure generally includes working pipe, insulation layer, and outer casing. In actual operation, the working pipe is in direct contact with high-temperature steam, and its thermal expansion and contraction deformation is larger than that of the outer casing in contact with the soil, which can easily lead to axial misalignment between the two, damage the overall structure of the direct buried steam insulation pipe, and affect its long-term stability.

[0003] The Chinese utility model patent with publication number CN218326893U provides a sliding support structure inside an underground steam insulation pipe, which realizes the axial dislocation movement of the working pipe and the outer sleeve through a roller group connected to the support structure. However, in this solution, the roller group and the support structure are both arranged inside the insulation layer, which causes the roller group to be blocked from rotating in actual applications and is difficult to play a role. In addition, the insulation layer has a single structure and is directly attached to the outer sleeve, which will lose a lot of heat during use. The Chinese utility model patent with publication number CN210567005U provides an underground sliding insulation steam pipe, which uses multiple groups of legs and arch plates to achieve axial dislocation movement between the working pipe and the outer sleeve. However, in this solution, the insulation layer is directly in contact with the leg structure, which can easily cause a large amount of heat to be lost through the legs in actual applications. In addition, the slender leg structure is prone to bending and damage due to uneven force distribution. It is worth noting that the insulation layer in the above two solutions is directly connected to the outer sleeve, which has a potential risk of water seepage and affects the normal operation of the pipeline.

[0004] In summary, developing a stable and efficient pipeline sliding structure while ensuring that the pipeline has excellent thermal insulation and waterproof capabilities is crucial to improving the overall performance of direct-buried steam insulated pipelines. Summary of the invention

[0005] The purpose of the present invention is to solve the deficiencies in the prior art and provide a zero thermal bridge external sliding waterproof direct buried steam insulation pipe and method. The purpose is to reduce the resistance of the direct buried steam insulation pipe when it undergoes axial displacement due to thermal expansion and contraction, enhance the thermal insulation performance of the direct buried steam insulation pipe, achieve effective waterproofing, and improve the long-term use stability of the direct buried steam insulation pipe.

[0006] The specific technical solutions adopted by the present invention are as follows:

[0007] In a first aspect, the present invention provides a zero-thermal-bridge external sliding waterproof direct-buried steam insulation pipeline, comprising a working pipe, an inner guide support and an outer sleeve; the outer wall of the working pipe is sequentially provided with an insulation cushion layer, an inorganic hard insulation layer and a sealing insulation layer from the inside to the outside; a closed insulation outer protective layer is arranged around the sealing insulation layer;

[0008] The outer sleeve is arranged on the periphery of the thermal insulation outer protective layer, and a plurality of groups of inner guide supports are arranged between the outer sleeve and the thermal insulation outer protective layer, and the inner guide supports are evenly distributed along the circumference of the longitudinal section of the pipeline; each group of inner guide supports includes a fixed sleeve, a pad, a first sliding block, a second sliding block and a fixing piece, and the curvature of the fixed sleeve, the pad, the first sliding block and the second sliding block are the same; the inner side of the fixed sleeve is fixedly connected to the thermal insulation outer protective layer through a plurality of fixing pieces; the pad is coaxially fixed to the outer side of the fixed sleeve; the first sliding block is fixed to the outer side of the pad, and the second sliding block is fixed to the inner side of the outer sleeve; the arc length of the second sliding block is greater than that of the first sliding block; there is a running gap between the first sliding block and the second sliding block; when the working pipe undergoes thermal expansion and deformation, a sliding fit is formed between the first sliding block and the second sliding block.

[0009] Preferably, the length of the second sliding block is at least twice the maximum thermal displacement length of the working tube during operation; and the operating clearance between the first sliding block and the second sliding block is less than 2 mm.

[0010] Preferably, four groups of inner guide supports are provided; the four groups of inner guide supports are evenly distributed along the circumference of the longitudinal section of the pipeline.

[0011] Preferably, the fixing sleeve is made of an arc-shaped thin steel plate, and the thickness of the arc-shaped thin steel plate is 1.5 mm to 5.0 mm.

[0012] Preferably, the fixing member is a rivet; after the fixing sleeve is fixedly connected to the thermal insulation outer sheath by the rivet, welding is used for further reinforcement.

[0013] Preferably, the first sliding block is made of a mirror stainless steel plate; the first sliding block is fixed to the outside of the pad by welding, and both ends of the first sliding block are bent toward the pad to form an arc for easy movement.

[0014] Preferably, the thermal insulation cushion layer is made of glass fiber felt, aluminum silicate felt or nano aerogel felt; the thickness of the thermal insulation cushion layer is 0.5 mm to 1.0 mm.

[0015] Preferably, the inorganic hard insulation layer is made of microporous calcium silicate or foamed calcium silicate material; and the sealing insulation layer is a polyurethane foam with a closed-cell structure.

[0016] Preferably, the thermal insulation outer sheath is made of galvanized steel sheet, which is rolled into a tube and covers the outer periphery of the sealing insulation layer; the outer sleeve is a steel sleeve.

[0017] In a second aspect, the present invention provides a method for improving the performance of a direct-buried steam insulation pipe, which is as follows:

[0018] The directly buried steam insulation pipeline of the first aspect is arranged underground, the outer side of the outer casing is in contact with the underground soil, and the interior of the working pipe is used to pass high-temperature steam;

[0019] Before the actual operation of the direct-buried steam insulated pipeline, high-temperature steam is not passed into the working pipe, so the working pipe does not undergo thermal expansion and deformation; there is a running gap between the first sliding block and the second sliding block, and no contact occurs; during actual operation, high-temperature steam is passed into the working pipe, and the working pipe undergoes thermal expansion and deformation due to the high-temperature steam and the change in underground temperature. When the working pipe undergoes axial deformation, the multi-layer insulation layer fixed on the periphery of the working pipe also deforms axially; the insulation outer sheath drives the first sliding block in the inner guide support to move axially, and at this time the first sliding block and the second sliding block contact and form a sliding fit; the friction resistance during axial misalignment is reduced by the sliding of the first sliding block and the second sliding block; the outer sleeve and the insulation outer sheath doubly block underground moisture from entering the insulation layer, and the insulation cushion layer, inorganic hard insulation layer, and sealing insulation layer continuously laid between the working pipe and the insulation outer sheath avoid thermal bridge effect, thereby improving waterproof and thermal insulation performance.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The steam insulation pipe provided by the present invention adopts an inner guide support to realize axial dislocation sliding between the working pipe and the outer sleeve, effectively avoiding displacement of the working pipe and the outer sleeve due to thermal expansion and contraction to damage the pipe structure, and enhancing the stability of the direct-buried steam insulation pipe in long-term operation. The sliding structure is reliable and stable, and it is not easy to be blocked by sliding or structural damage.

[0022] (2) In the present invention, the inner guide support is installed outside the thermal insulation outer sheath, and there is no thermal bridge effect between the working pipe and the thermal insulation outer sheath, which greatly improves the thermal insulation performance of the pipeline. In addition, the thermal insulation layer adopts a fully sealed structure, which effectively suppresses the convection phenomenon inside and outside the thermal insulation layer, further enhancing the thermal insulation effect.

[0023] (3) In the present invention, both the thermal insulation outer sheath and the outer sleeve are made of a steel closed structure to prevent moisture from entering the interior of the thermal insulation layer, serving as a double barrier to achieve efficient waterproofing. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of an external sliding waterproof direct buried steam insulation pipeline provided in this embodiment;

[0025] Figure 2 for Figure 1AA section diagram of Chinese and foreign sliding waterproof direct buried steam insulation pipeline;

[0026] In the figure: working pipe 1, thermal insulation cushion layer 2, inorganic hard thermal insulation layer 3, sealing thermal insulation layer 4, thermal insulation outer protective layer 5, inner guide support 6, outer sleeve 7, fixed sleeve 8, pad 9, first sliding block 10, second sliding block 11, and fixing part 12. DETAILED DESCRIPTION

[0027] The present invention is further described and illustrated below in conjunction with the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly without conflicting with each other.

[0028] like Figure 1 and Figure 2 As shown, as a preferred embodiment of the present invention, this embodiment provides a zero thermal bridge external sliding waterproof direct buried steam insulation pipeline, including a working pipe 1, an inner guide support 6 and an outer sleeve 7. The outer wall of the working pipe 1 is successively provided with an insulation cushion layer 2, an inorganic hard insulation layer 3 and a sealing insulation layer 4 from the inside to the outside.

[0029] The thermal insulation cushion layer 2 is made of glass fiber felt, aluminum silicate felt or nano aerogel felt. The thickness of the thermal insulation cushion layer 2 is 0.5 mm to 1.0 mm. The thermal insulation cushion layer 2 can ensure that the working pipe 1 is closely fitted with the inorganic hard thermal insulation layer 3, provide a certain thermal insulation effect for the working pipe 1, and provide a certain shock absorption effect for the inorganic hard thermal insulation layer 3. The inorganic hard thermal insulation layer 3 is made of microporous calcium silicate or foamed calcium silicate material. The inorganic hard thermal insulation layer 3 provides the main thermal insulation effect for the working pipe 1 and can support the weight of the working pipe 1.

[0030] The sealing insulation layer 4 is a polyurethane foam with a closed-cell structure, that is, a rigid polyurethane foam plastic. The air flow in the closed-cell structure is poor, and the thermal conductivity is low, which prevents convection heat exchange inside and outside the insulation layer. The sealing insulation layer 4 can provide a certain insulation effect, and generate pressure during the foaming process, so that the working pipe 1 and the insulation layer become a whole. In addition, the closed-cell structure makes it difficult for moisture to penetrate, preventing external moisture from entering the insulation layer and avoiding a decrease in the insulation effect.

[0031] like Figure 2 As shown, a closed thermal insulation outer sheath 5 is arranged on the periphery of the sealing thermal insulation layer 4. An outer sleeve 7 is sleeved on the periphery of the thermal insulation outer sheath 5. In this embodiment, the thermal insulation outer sheath 5 is made of galvanized steel plate, which is rolled into a tube and covers the periphery of the sealing thermal insulation layer 4. While protecting the internal thermal insulation layer structure, it provides a closed space for the foaming process of the sealing thermal insulation layer 4. In this embodiment, the outer sleeve 7 is a steel sleeve, which can resist the underground soil pressure and protect the steam insulation pipeline. By arranging the thermal insulation outer sheath 5 and the outer sleeve 7, a double waterproof structure is formed to block external moisture. It is prevented that external moisture enters the thermal insulation layer, thereby affecting the thermal insulation effect.

[0032] In the device provided by the present invention, a plurality of groups of inner guide supports 6 are arranged between the outer sleeve 7 and the thermal insulation outer sheath 5, and the inner guide supports 6 are evenly distributed along the longitudinal section of the pipeline to stably support the steam thermal insulation pipeline and realize reliable and stable sliding. In this embodiment, four groups of inner guide supports 6 are arranged. The four groups of inner guide supports 6 are evenly distributed along the longitudinal section of the pipeline, and the angle between adjacent inner guide supports 6 is 90°.

[0033] Each group of inner guide supports 6 includes a fixed sleeve 8, a pad 9, a first sliding block 10, a second sliding block 11 and a fixing member 12, and the fixed sleeve 8, the pad 9, the first sliding block 10 and the second sliding block 11 have the same curvature. The inner side of the fixed sleeve 8 is fixedly connected to the thermal insulation outer sheath 5 by a plurality of fixing members 12. In this embodiment, the fixed sleeve 8 is made of a circular arc thin steel plate, the thickness of the circular arc thin steel plate is 1.5mm to 5.0mm, and the fixing member 12 is a rivet. After the fixed sleeve 8 is fixedly connected to the thermal insulation outer sheath 5 by rivets, welding is further used to reinforce it. The outer side of the fixed sleeve 8 is coaxially fixed with an arc-shaped pad 9 by welding. The first sliding block 10 is fixed on the outer side of the pad 9, and the second sliding block 11 is fixed on the inner side of the outer sleeve 7. The arc length of the second sliding block 11 is greater than that of the first sliding block 10, and the length of the second sliding block 11 is at least twice the maximum thermal displacement length when the working tube 1 is in operation.

[0034] In this embodiment, the first sliding block 10 is made of a mirror stainless steel plate. The first sliding block 10 is fixed to the outside of the pad 9 by welding, and the two ends of the first sliding block 10 are bent toward the pad 9 to form an arc that is easy to move. The second sliding block 11 is made of a material with low surface friction, such as SF-1 composite plate. When the working tube 1 and the outer sleeve 7 undergo axial displacement due to thermal expansion and contraction, a sliding fit is formed between the first sliding block 10 and the second sliding block 11 to reduce the sliding friction. When no axial displacement occurs. There is a running gap of less than 2 mm between the first sliding block 10 and the second sliding block 11 to meet the assembly and operation requirements. It should be noted that the present invention does not limit the specific material of the second sliding block 11, and those skilled in the art can choose according to actual needs. When other materials are used, the running gap between the first sliding block 10 and the second sliding block 11 can be selected considering factors such as the actual deformation rate.

[0035] This embodiment also provides a method for improving the performance of the external sliding waterproof direct buried steam insulation pipeline using the above zero thermal bridge, which is as follows:

[0036] The above-mentioned direct-buried steam insulation pipeline is set underground, the outer side of the outer casing 7 is in contact with the underground soil, and the inside of the working pipe 1 is used to pass high-temperature steam.

[0037] Before the direct-buried steam insulation pipeline is actually put into operation, high-temperature steam is not introduced into the working pipe 1, so the working pipe 1 does not undergo thermal expansion and deformation. There is a running gap between the first sliding block 10 and the second sliding block 11, and no contact occurs. During actual operation, high-temperature steam is introduced into the working pipe 1, and the working pipe 1 undergoes thermal expansion and deformation due to the high-temperature steam and the change in underground temperature. When the working pipe 1 undergoes axial deformation, the multi-layer insulation layer fixed on the periphery of the working pipe 1 also deforms axially. The thermal insulation outer sheath 5 drives the first sliding block 10 in the inner guide support 6 to move axially, and at this time, the first sliding block 10 and the second sliding block 11 contact and form a sliding fit. The friction resistance during axial misalignment is reduced by the sliding of the first sliding block 10 and the second sliding block 11.

[0038] The inner guide support 6 is installed on the outside of the thermal insulation outer sheath 5 to ensure that the space between the working pipe 1 and the thermal insulation outer sheath 5 is evenly and continuously filled with the thermal insulation cushion layer 2, the inorganic hard thermal insulation layer 3 and the sealing thermal insulation layer 4, without generating a thermal bridge effect, thereby significantly improving the thermal insulation performance of the pipeline.

[0039] The thermal insulation outer sheath 5 and the outer sleeve 7 both adopt a closed structure. The outer sleeve 7 blocks moisture in the soil from entering between the outer sleeve 7 and the thermal insulation outer sheath 5. When water seepage occurs in the outer sleeve 7, the thermal insulation outer sheath 5 further blocks moisture from entering the interior of the thermal insulation layer, serving as a double barrier to achieve efficient waterproofing.

[0040] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A zero thermal bridge external sliding waterproof direct buried steam insulation pipeline, characterized in that: It comprises a working tube (1), an inner guide support (6) and an outer sleeve (7); the outer wall of the working tube (1) is provided with a thermal insulation cushion layer (2), an inorganic hard thermal insulation layer (3) and a sealing thermal insulation layer (4) in sequence from the inside to the outside; and a closed thermal insulation outer protective layer (5) is provided on the periphery of the sealing thermal insulation layer (4); The outer sleeve (7) is sleeved on the outer periphery of the thermal insulation outer sheath (5), and a plurality of groups of inner guide supports (6) are arranged between the outer sleeve (7) and the thermal insulation outer sheath (5), and the inner guide supports (6) are evenly distributed along the circumference of the longitudinal section of the pipeline; each group of inner guide supports (6) comprises a fixed sleeve (8), a backing plate (9), a first sliding block (10), a second sliding block (11) and a fixing member (12), and the curvature of the fixed sleeve (8), the backing plate (9), the first sliding block (10) and the second sliding block (11) are the same; the inner side of the fixed sleeve (8) is provided with a plurality of inner guide supports (6) The fixing member (12) is fixedly connected to the thermal insulation outer protective layer (5); the pad (9) is coaxially fixed on the outer side of the fixing sleeve (8); the first sliding block (10) is fixed on the outer side of the pad (9), and the second sliding block (11) is fixed on the inner side of the outer sleeve (7); the arc length of the second sliding block (11) is greater than that of the first sliding block (10); there is a running gap between the first sliding block (10) and the second sliding block (11); when the working tube (1) undergoes thermal expansion and deformation, a sliding fit is formed between the first sliding block (10) and the second sliding block (11).

2. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The length of the second sliding block (11) is at least twice the maximum thermal displacement length of the working tube (1) during operation; and the operating clearance between the first sliding block (10) and the second sliding block (11) is less than 2 mm.

3. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The inner guide supports (6) are arranged in four groups; the four groups of inner guide supports (6) are evenly distributed along the circumference of the longitudinal section of the pipeline.

4. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The fixing sleeve (8) is made of an arc-shaped thin steel plate, and the thickness of the arc-shaped thin steel plate is 1.5 mm to 5.0 mm.

5. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The fixing member (12) is a rivet; after the fixing sleeve (8) is fixedly connected to the thermal insulation outer protective layer (5) by the rivet, welding is used for further reinforcement.

6. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The first sliding block (10) is made of a mirror-finished stainless steel plate; the first sliding block (10) is fixed to the outside of the pad (9) by welding, and both ends of the first sliding block (10) are bent toward the pad (9) to form an arc that is easy to move.

7. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The thermal insulation cushion layer (2) is made of glass fiber felt, aluminum silicate felt or nano aerogel felt; the thickness of the thermal insulation cushion layer (2) is 0.5 mm to 1.0 mm.

8. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1 is characterized in that: The inorganic hard thermal insulation layer (3) is made of microporous calcium silicate or foamed calcium silicate material; the sealing thermal insulation layer (4) is polyurethane foam with a closed-cell structure.

9. The zero thermal bridge external sliding waterproof direct buried steam insulation pipeline according to claim 1, characterized in that: The thermal insulation outer protective layer (5) is made of galvanized steel sheet, which is rolled into a tube and covers the outer periphery of the sealing thermal insulation layer (4); the outer sleeve (7) is a steel sleeve.

10. A method for improving the performance of a direct-buried steam insulation pipeline, characterized in that: The details are as follows: The directly buried steam insulation pipeline according to any one of claims 1 to 9 is arranged underground, the outer side of the outer casing (7) is in contact with the underground soil, and the interior of the working pipe (1) is used to pass high-temperature steam; Before the direct-buried steam insulation pipeline is actually operated, high-temperature steam is not introduced into the working pipe (1), so that the working pipe (1) does not undergo thermal expansion and deformation; there is an operating gap between the first sliding block (10) and the second sliding block (11), and no contact occurs; during actual operation, high-temperature steam is introduced into the working pipe (1), and the working pipe (1) undergoes thermal expansion and deformation due to the high-temperature steam and the change in underground temperature. When the working pipe (1) undergoes axial deformation, the multi-layer insulation layer fixed to the outer periphery of the working pipe (1) also undergoes axial deformation; the insulation outer sheath (5) drives the inner guide support The first sliding block (10) in (6) moves axially, and at this time, the first sliding block (10) and the second sliding block (11) are in contact and form a sliding fit; the friction resistance during axial misalignment is reduced by the sliding of the first sliding block (10) and the second sliding block (11); the outer sleeve (7) and the thermal insulation outer sheath (5) double-block underground moisture from entering the interior of the thermal insulation layer; the thermal insulation cushion layer (2), the inorganic hard thermal insulation layer (3), and the sealing thermal insulation layer (4) continuously laid between the working pipe (1) and the thermal insulation outer sheath (5) avoid the thermal bridge effect, thereby achieving improved waterproof and thermal insulation performance.

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