CN210800458U - Flexible joint for prefabricated overhead heat-insulation pipe - Google Patents
Flexible joint for prefabricated overhead heat-insulation pipe Download PDFInfo
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- CN210800458U CN210800458U CN201921213893.2U CN201921213893U CN210800458U CN 210800458 U CN210800458 U CN 210800458U CN 201921213893 U CN201921213893 U CN 201921213893U CN 210800458 U CN210800458 U CN 210800458U
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Abstract
The utility model discloses a flexible joint for prefabricated overhead heat-insulating pipes, which comprises at least one layer of main heat-insulating layer wrapped on the outer surface of a core pipe, wherein aluminum foil glass fiber cloth is wound on each layer of heat-insulating layer to form a reflecting layer, and a damp-proof layer and a metal outer protective layer are sequentially wound from inside to outside the outermost reflecting layer; the longitudinal and circular seams of each main heat insulation layer, the reflection layer and the moisture-proof layer are staggered, and the seams are lapped; two ends of the metal outer protection layer of the flexible joint are lapped with the metal outer protection layer of the prefabricated overhead heat-insulation pipe, and the metal outer protection layer of the flexible joint is arranged outside the metal outer protection layer of the prefabricated overhead heat-insulation pipe; the metal outer protective layer of the flexible joint is in lap joint with the seam, and one end of the metal outer protective layer of the flexible joint is fixed by a rivet along the radial direction. The utility model discloses according to the pre-extension amount of core pipe, give soft insulation material certain precompression volume, soft insulation material also can extend thereupon when guaranteeing core pipe thermal expansion, can not produce naked pipe, plays the thermal compensation effect, the utility model discloses easy to carry out, easy operation.
Description
Technical Field
The utility model relates to a flexible joint for prefabricated built on stilts insulating tube, in particular to flexible joint that is used for stereoplasm insulation material to make heat retaining prefabricated built on stilts finished product pipe.
Background
Along with the defects of the traditional steam long-distance heat preservation technology are gradually exposed, new heat preservation products are gradually developed, a novel prefabricated overhead heat preservation pipe technology represented by a prefabricated overhead heat preservation pipe structure (with the authorization notice number of CN 203082382U) is gradually applied in recent years, the heat preservation pipes mostly adopt a tile-foam composite type hard heat preservation structure formed by hard calcium silicate and hard polyurethane foam, and the long-term safe and stable operation can be realized only by simply processing joints on a construction site. Conventional methods for such joint treatment are: by adopting a cast-in-place rigid polyurethane foam method, the core pipe can generate thermal displacement after being heated and expanded, and the external rigid heat-insulating material can not displace along with the core pipe, so that an outer protective layer and the heat-insulating material on the pipe section with larger thermal expansion quantity on the whole pipeline are pulled away, the core pipe is exposed, and serious heat loss is generated; in addition, the cast-in-place polyurethane foam technology is influenced by the environmental temperature and the construction level, the foam density and uniformity cannot be controlled, the performance of the foam cannot be guaranteed, and heat loss can be caused when the foam is not well treated.
SUMMERY OF THE UTILITY MODEL
The utility model aims at solving the problem that the existing prefabricated overhead thermal insulation pipe adopts the cast-in-place rigid polyurethane foam method to carry out joint treatment, providing a flexible joint for the prefabricated overhead thermal insulation pipe, adopting flexible soft thermal insulation material in the method, not relating to on-site foaming, having controllable heat preservation, improving the overall thermal insulation performance of the prefabricated overhead thermal insulation pipe network
The utility model aims at realizing through the following technical scheme:
the utility model provides a prefabricated built on stilts flexible joint for heat preservation pipe, includes at least one deck main heat preservation of core pipe surface parcel, twines the fine cloth of aluminium foil glass at every layer heat preservation and forms the reflection stratum, twines dampproof course and metal outer jacket outward by interior in proper order outside outmost reflection stratum.
The longitudinal and circular seams of each main heat insulation layer, the reflection layer and the moisture-proof layer are staggered, and the seams are lapped; the abutted seam can not be arranged in the range of 45 degrees right above and below. The outer sides of each main heat-insulating layer, each reflecting layer and each moisture-proof layer are fixed by galvanized steel strips, and the gap between every two adjacent galvanized steel strips cannot be larger than 20 cm.
The main heat insulation material of the main heat insulation layer comprises but is not limited to soft heat insulation materials such as aluminum silicate blankets and glass wool. When the temperature of the medium in the pipe is more than or equal to 300 ℃, the main heat-insulating material is an aluminum silicate blanket and glass wool, and the safe use temperature of the glass wool is 300 ℃, so that the main heat-insulating layer close to the core pipe adopts the aluminum silicate blanket as the main heat-insulating material, and when the temperature is reduced to be within 300 ℃, the main heat-insulating layer adopts the glass wool as the main heat-insulating material. When the temperature of the medium in the pipe is less than 300 ℃, the main heat-insulating material adopts glass wool.
The number of layers of the main insulating layer is determined according to the temperature of the medium.
The actual length L1 of the main heat-insulating layer tightly attached to the surface of the core pipe is greater than the length L2 of the exposed core pipe, and the reserved elongation delta L of the heat-insulating material is L1-L2; Δ L is 2 × Δ L, and Δ L is the amount of thermal expansion generated by each core tube at the medium temperature;
Δl＝α(t0-ta) Wherein:
α -coefficient of thermal expansion of core tube, cm/(m. degree. C.);
t0-temperature of the medium in the pipe, DEG C,
ta-ambient temperature, deg.c.
The reflecting layer is formed by winding aluminum foil glass fiber cloth on the outer side of the main heat insulation layer, so that the heat insulation performance of the whole composite heat insulation structure is better.
The dampproof course form at outmost reflection stratum by the winding of nanometer bubble chamber membrane, avoid inside insulation material to wet, prolong flexible joint's life.
The thickness of the metal outer protective layer is 0.5-1 mm, and metal materials such as galvanized iron sheets, aluminum-plated thin plates and the like are generally adopted; the color of the metal outer protective layer is consistent with that of the metal outer protective layer of the prefabricated finished product pipe, and most of the metal outer protective layer is green or grey, silver and the like.
The flexible joint for the prefabricated overhead heat-insulating pipe is a trapezoidal joint and is perfectly butted with trapezoidal interfaces at two ends of the prefabricated overhead heat-insulating pipe.
Two ends of the metal outer protective layer of the flexible joint for the prefabricated overhead heat-insulating pipe are lapped with the metal outer protective layer of the prefabricated overhead heat-insulating pipe, the metal outer protective layer of the flexible joint is arranged outside, the metal outer protective layer of the prefabricated overhead heat-insulating pipe is arranged inside, and the lapping length is not less than 5 cm;
preferably, one end of the metal outer protection layer of the flexible joint is fixed with the metal outer protection layer of the prefabricated overhead heat-insulation pipe by a rivet along the radial direction, and the other end of the metal outer protection layer of the flexible joint is not fixed, so that the metal outer protection layer of the flexible joint and the metal outer protection layer of the prefabricated overhead heat-insulation pipe can freely slide along with the expansion and contraction of the core pipe, and the metal outer protection layer of the prefabricated overhead heat-insulation pipe is prevented from.
Preferably, the metal outer protective layer of the flexible joint for the prefabricated overhead heat-insulating pipe is lapped and spliced, and the lapping length of the spliced position is not less than 5 cm.
A method for processing a flexible joint for a prefabricated overhead heat-insulating pipe comprises the following steps: firstly, hoisting prefabricated overhead heat-insulating pipes in place, butt-welding core pipes and checking welding seams, forming a groove between an exposed core pipe between two adjacent prefabricated overhead heat-insulating pipes and trapezoidal joints of the prefabricated overhead heat-insulating pipes on two sides, wrapping the exposed core pipe by adopting a soft main heat-insulating material to form a main heat-insulating layer, wherein the number of the main heat-insulating layer is at least one, and wrapping aluminum foil glass fiber cloth outside each main heat-insulating layer to form a reflecting layer; the moisture-proof layer and the metal outer protective layer are sequentially wrapped outside the outermost reflecting layer; the metal outer protection layer is connected with the metal outer protection layer of the prefabricated overhead heat-insulation pipe in an overlapping mode, the metal outer protection layer of the flexible joint is arranged on the outer side of the metal outer protection layer of the prefabricated overhead heat-insulation pipe, one end of the metal outer protection layer of the flexible joint is fixed with the metal outer protection layer of the prefabricated overhead heat-insulation pipe through a rivet along the radial direction, and the other end of the metal outer protection layer of the flexible joint is not fixed.
The utility model has the advantages as follows:
1. the flexible joint for the prefabricated overhead heat-insulating pipe adopts a composite heat-insulating structure, a trapezoidal structure is presented between each layer of heat insulation at the two ends of the flexible joint, and the trapezoidal interfaces at the two ends of the prefabricated overhead heat-insulating pipe are perfectly butted, so that the heat insulation can be carried out on the core pipe joint part, and the heat-insulating effect is good; the heat insulating material is spliced in a staggered mode, so that a heat transfer path is prolonged, and heat loss at joints is reduced. And a layer of aluminum foil glass fiber cloth is wound outside each layer of main heat insulation material to form a reflecting layer, so that the heat insulation performance of the whole composite heat insulation structure is better.
2. According to the pre-extension amount of the core pipe, a certain pre-compression amount is given to the soft heat-insulating material of the flexible joint, the soft heat-insulating material absorbs the thermal expansion of the pipeline when the core pipe is heated to expand, the soft heat-insulating material can also extend along with the core pipe when the core pipe is heated to expand, the bare pipe and the metal outer protective layer cannot be pulled open, the heat compensation effect is achieved on the whole pipe network when the attractiveness is guaranteed, and the safe and effective operation of the pipe network is guaranteed.
3. The utility model discloses prefabricated built on stilts heat preservation is with flexible joint design compactness, convenient construction.
Drawings
FIG. 1 is a structural overall view of a flexible joint for a prefabricated overhead heat-insulating pipe;
FIG. 2 is a partial view of a flexible joint structure for a prefabricated overhead heat-insulating pipe;
FIG. 3 is a schematic view of the overlapping and seam-splicing treatment of the metal outer protective layer of the flexible joint for the prefabricated overhead heat-insulating pipe;
FIG. 4 is a schematic view of a metal outer protective layer lapping process of a flexible joint for a prefabricated overhead heat-insulating pipe;
in the figure: 1-a core tube; 2-a first main insulating layer; 3 — a first reflective layer; 4-a second main insulating layer; 5, prefabricating a metal outer protective layer for the overhead heat-insulating pipe; 6-moisture barrier; 7, a metal outer protective layer for the flexible joint; 8, riveting; 9, prefabricating trapezoidal joints at two ends of the finished pipe; 10-welding seam.
Detailed Description
The technical solution of the present invention will be further explained with reference to the accompanying drawings and examples.
Example 1
As shown in figure 1, in the application of the prefabricated overhead heat-insulating pipe technology, the prefabricated overhead heat-insulating pipes are hoisted in place, core pipes are butt-welded and welding seams 10 are checked, and a groove is formed between an exposed core pipe between two adjacent prefabricated overhead heat-insulating pipes and trapezoidal joints 9 of the prefabricated overhead heat-insulating pipes on two sides.
As shown in fig. 2-4, a flexible joint for a prefabricated overhead thermal insulation pipe is a trapezoidal joint and forms a seamless butt joint with trapezoidal joints at two ends of the prefabricated overhead thermal insulation pipe shown in fig. 1; the core pipe comprises a first main heat-insulating layer 2, a first reflecting layer 3, a second main heat-insulating layer 4, a second reflecting layer, a moisture-proof layer 6 and a metal outer protective layer 7 for a flexible joint, which are sequentially wrapped on the outer surface of a core pipe 1; wherein, the longitudinal and circular seams of each layer of main insulating layer, reflecting layer and damp-proof layer are staggered, and the seams are lapped; the abutted seam can not be arranged in the range of 45 degrees right above and below; the outer sides of each main heat-insulating layer, each reflecting layer and each moisture-proof layer are fixed by galvanized steel strips, and the gap between every two adjacent galvanized steel strips cannot be larger than 20 cm; two ends of the metal outer protection layer 7 for the flexible joint are axially overlapped with the metal outer protection layer 5 for the prefabricated overhead heat-insulating pipe under the pipeline, the overlapping length is not less than 5cm, the metal outer protection layer 7 for the flexible joint is arranged outside, and the metal outer protection layer 5 for the prefabricated overhead heat-insulating pipe is arranged inside and fixed by a rivet 8; the flexible joint is with 7 piece joints of metal outer jacket, and piece joint department overlap joint length is not less than 5cm, and flexible joint is with 7 one end of metal outer jacket radially with rivet 8 fixed, and the other end is unfixed, can guarantee that can freely slide along with the expend with heat and contract with cold of inside core pipe between the interior outer protective layer, be unlikely to be torn.
When the temperature of the medium in the pipe is more than or equal to 300 ℃, the main heat-insulating material of the main heat-insulating layer selects an aluminum silicate blanket and glass wool; when the temperature of the medium in the pipe is less than 300 ℃, the main heat-insulating material adopts glass wool.
The actual length L1 of the first main insulating layer 2 tightly attached to the surface of the core pipe 1 and the length L2 of the exposed core pipe are required to be L2 < L1, and L1-L2 is Δ L (Δ L is the reserved elongation of the insulating material). Δ L is related to the amount of thermal expansion Δ L generated at the temperature of the medium in each core tube, where Δ L is 2 × Δ L,
specific calculation of Δ l is as follows, Δ l is α (t)0-ta) Wherein:
α -coefficient of thermal expansion of core tube, cm/(m. degree. C.);
t0-temperature of the medium in the pipe, DEG C,
ta-ambient temperature, deg.c.
For example: 500m steam pipeline with temperature ta20 ℃ to t0At 270 ℃, the linear expansion coefficient of the pipeline is 0.001234cm/(m DEG C), the length of the pipeline is increased by about 1500mm, the elongation of 2 prefabricated heat-insulating pipes is about l4.8cm when the length of the heat-insulating material reserved elongation delta L is 9.6cm, and the length of the pipeline is reduced to two 12.5m pipelines.
Specifically, the reflecting layer is formed by winding aluminum foil glass fiber cloth on each insulating layer; the moisture-proof layer is formed by winding a nano bubble film on the outermost reflecting layer.
The flexible joint for the prefabricated overhead heat-insulating pipe in the embodiment 1 is applied to the field of prefabricated overhead steam conveying, and the construction method comprises the following steps: firstly, hoisting prefabricated overhead heat-insulating pipes in place, welding exposed core pipe joints, performing surface treatment on core pipes, and forming grooves between the exposed core pipes between two adjacent prefabricated overhead heat-insulating pipes and the trapezoidal joints of the prefabricated overhead heat-insulating pipes on two sides; the exposed core pipe is wrapped by soft main heat insulation materials to form a main heat insulation layer, the number of layers of the main heat insulation layer is two, and aluminum foil glass fiber cloth is wrapped outside each layer of the heat insulation layer to form a reflection layer; the moisture-proof layer and the metal outer protective layer are sequentially wrapped outside the outermost reflecting layer; two ends of the metal outer protection layer are axially lapped with the metal outer protection layer of the prefabricated overhead heat-insulation pipe, the metal outer protection layer of the flexible joint is arranged outside, and the metal outer protection layer of the prefabricated overhead heat-insulation pipe is arranged inside and fixed by a rivet 8; the flexible joint is spliced by a metal outer protection layer 7, one end of the metal outer protection layer 7 of the flexible joint is fixed with the metal outer protection layer of the prefabricated overhead heat-insulation pipe by a rivet along the radial direction, and the other end of the metal outer protection layer is not fixed.
The trapezoidal joints at the two ends of the flexible joint formed by the method are in seamless butt joint with the trapezoidal joints at the two ends of the prefabricated finished pipe, the joints are tightly lapped, and the heat preservation effect is good; the pre-compression amount of the heat insulation material and the splicing seam between the heat insulation materials are strictly controlled, so that the flexible joint with the heat compensation effect is formed. When the heat insulation core pipe is used, after the temperature rises, the core pipe 1 is heated to expand, the first main heat insulation layer 2, the first reflection layer 3, the second main heat insulation layer 4, the second reflection layer, the moisture-proof layer 6 and the metal outer protection layer 7 for the flexible joint are also stretched accordingly, no bare pipe is generated, and the heat insulation effect is good.
The above is only one embodiment of the present invention, and all modifications, equivalent replacements, improvements and the like made within the spirit and principle of the present invention are included in the protection scope of the present invention.
Claims (9)
1. The utility model provides a prefabricated built on stilts flexible joint for heat preservation pipe which characterized in that includes at least one deck main heat preservation of core pipe surface parcel, twines aluminium foil glass fiber cloth at every layer heat preservation and forms the reflection stratum, twines dampproof course and metal outer jacket outward in proper order outside outmost reflection stratum.
2. The flexible joint for the prefabricated overhead heat-insulating pipe as claimed in claim 1, wherein the actual length L1 of the main heat-insulating layer tightly attached to the surface of the core pipe is greater than the length L2 of the exposed core pipe, and the reserved elongation delta L of the heat-insulating material is L1-L2;
Δ L is 2 × Δ L, and Δ L is the amount of thermal expansion generated at the medium temperature in each core tube.
3. The flexible joint for the prefabricated overhead heat-insulating pipe according to claim 1, wherein longitudinal and circular seams of each main heat-insulating layer, each reflecting layer and each moisture-proof layer are staggered, and the seams are overlapped; the abutted seam can not be arranged in the range of 45 degrees right above and below; the outer sides of each main heat-insulating layer, each reflecting layer and each moisture-proof layer are fixed by galvanized steel strips.
4. The flexible joint for prefabricated overhead thermal insulation pipes as claimed in claim 1, wherein the main thermal insulation material of the main thermal insulation layer is an aluminum silicate blanket and/or a glass wool.
5. The flexible joint for the prefabricated overhead heat-insulating pipe as claimed in claim 1 or 4, wherein when the temperature of the medium in the pipe is more than or equal to 300 ℃, the main heat-insulating material is selected from an aluminum silicate blanket and glass wool; when the temperature of the medium in the pipe is less than 300 ℃, the main heat-insulating material adopts glass wool.
6. The flexible joint for the prefabricated overhead thermal insulation pipe according to claim 1, wherein the reflection layer is formed by winding aluminum foil fiberglass cloth on the outer side of the main thermal insulation layer; the moisture-proof layer is formed by winding a nano bubble film on the outermost reflecting layer.
7. The flexible joint for the prefabricated overhead heat-insulating pipe as claimed in claim 1, wherein the metal outer sheath has a thickness of 0.5-1 mm, such as galvanized iron sheet and aluminum-plated thin plate.
8. The flexible joint for the prefabricated overhead heat-insulating pipe according to claim 1, wherein two ends of the metal outer sheath of the flexible joint for the prefabricated overhead heat-insulating pipe are lapped with the metal outer sheath of the prefabricated overhead heat-insulating pipe, and the metal outer sheath of the flexible joint is arranged outside the metal outer sheath of the prefabricated overhead heat-insulating pipe; the metal outer protective layer of the flexible joint is in lap joint with the seam, one end of the metal outer protective layer of the flexible joint is fixed with the metal outer protective layer of the prefabricated overhead heat-insulation pipe by rivets along the radial direction, and the other end of the metal outer protective layer of the flexible joint is not fixed.
9. The flexible joint for the prefabricated overhead heat-insulating pipe according to claim 1, wherein two ends of the metal outer sheath of the flexible joint for the prefabricated overhead heat-insulating pipe are axially overlapped with the metal outer sheath of the prefabricated overhead heat-insulating pipe under a pipeline, the overlapping length is not less than 5cm, and the flexible joint is fixed by rivets.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201921213893.2U CN210800458U (en) | 2019-07-30 | 2019-07-30 | Flexible joint for prefabricated overhead heat-insulation pipe |
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| CN201921213893.2U CN210800458U (en) | 2019-07-30 | 2019-07-30 | Flexible joint for prefabricated overhead heat-insulation pipe |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113566053A (en) * | 2021-06-28 | 2021-10-29 | 泰州金泰环保热电有限公司 | Thermal pipeline insulation structure and laying method |
| CN114484154A (en) * | 2022-01-29 | 2022-05-13 | 北京天济明科技有限公司 | Low-deformation small-gap high-sealing special-shaped-section high-temperature pipeline heat insulation system |
| CN116066634A (en) * | 2023-01-04 | 2023-05-05 | 江苏中圣管道工程技术有限公司 | Detachable prefabricated heat preservation pipe |
-
2019
- 2019-07-30 CN CN201921213893.2U patent/CN210800458U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113566053A (en) * | 2021-06-28 | 2021-10-29 | 泰州金泰环保热电有限公司 | Thermal pipeline insulation structure and laying method |
| CN114484154A (en) * | 2022-01-29 | 2022-05-13 | 北京天济明科技有限公司 | Low-deformation small-gap high-sealing special-shaped-section high-temperature pipeline heat insulation system |
| CN116066634A (en) * | 2023-01-04 | 2023-05-05 | 江苏中圣管道工程技术有限公司 | Detachable prefabricated heat preservation pipe |
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