A discontinuous prefabricated overhead insulated pipe and a manufacturing method thereof

Abstract

The present invention discloses an intermittent prefabricated overhead insulated pipe and a manufacturing method thereof, which relate to the technical field of long-distance steam transportation; the insulated pipe comprises a core pipe, an inner lining layer and an outer protective pipe, and a plurality of hard insulation sections and soft insulation sections arranged between the inner lining layer and the outer protective pipe, the hard insulation sections and the soft insulation sections are wrapped on the outside of the inner lining layer, and are arranged in a staggered manner along the length direction of the core pipe, and the hard insulation sections and the soft insulation sections are overlapped by insulation materials; an organic insulation layer is arranged on the inside of the outer protective pipe, and the organic insulation layer is used to tightly wrap the hard insulation sections and the soft insulation sections inside it together. By implementing this technical solution, the manufactured insulated pipe can achieve the effect of bearing the operating load of the heating network and taking into account the insulation function, and has excellent insulation performance, low thermal conductivity, light weight, which will significantly reduce the energy loss of the thermal network, and be applied in the field of prefabricated overhead steam transportation to achieve safety, stability, high efficiency and energy saving of the entire pipeline network.

Description

Technical Field

[0001] The invention relates to the technical field of long-distance steam transportation, in particular to an intermittent prefabricated overhead insulated pipe and a manufacturing method thereof. Background Art

[0002] As environmental problems become increasingly severe, the energy sector has higher and higher requirements for energy conservation and emission reduction. The construction scale of thermal power plants and the corresponding heat networks has developed rapidly, and the requirements for heat network insulation technology have also become higher and higher. As a result, the disadvantages of traditional insulation technology have gradually been exposed, and the development and application of finished insulated pipes have received more and more attention from countries around the world.

[0003] As far as steam pipe insulation technology is concerned, the current prefabricated insulation pipe structures can be summarized into three types: all-soft insulation structure, all-hard insulation structure, and hard-soft composite insulation structure. However, according to the inventors in practice, they found that the above-mentioned finished insulated pipes also showed their own shortcomings when facing the challenges of support, insulation, processing, etc., such as: the use of all-soft insulation material insulation structure has the problem of difficult support, the soft insulation material at the pipe support position is easily flattened, resulting in insulation failure at this location, and the pipeline installation height is difficult to ensure; the use of all-hard insulation structure is expensive and heavy, and has high requirements on the strength of the pipe support and the foundation structure, and the insulation effect is average; the use of hard + soft insulation structure is not easy to process, and the hard polyurethane is directly foamed outside the soft insulation material. The foaming material will squeeze and deform the internal soft material, resulting in the inability to ensure the insulation thickness, etc. The above problems have exposed that there is still room for optimization in the design, processing, installation and other links of the finished insulated pipe.

[0004] In view of the problems exposed by the existing finished insulation pipe technology, technical personnel in this field are urgently needed to develop a new type of discontinuous prefabricated overhead insulation pipe with reliable supporting function, good insulation effect and easy processing, which is of great significance for industrial application. Summary of the invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide an intermittent prefabricated overhead insulated pipe and a manufacturing method thereof, which is combined with a structural design in which hard insulation sections and soft insulation sections are staggered along the length direction of the core pipe, so as to achieve the effect of bearing the operating load of the heating network and taking into account the insulation function, so that the hard insulation section of the insulation pipe itself is connected with the pipe support, and the support strength is high, which provides a strong safety guarantee for the long-term operation of the thermal network; and the soft insulation section has excellent insulation performance, low thermal conductivity, and light weight, which will significantly reduce the energy loss of the thermal network. At the same time, the overall structural design has good structural strength. It is applied in the field of prefabricated overhead steam transportation to achieve safety, stability, high efficiency and energy saving of the entire pipeline network, and has good application prospects and promotion value.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A discontinuous prefabricated overhead insulated pipe comprises a core pipe, an inner lining layer and an outer protective pipe which are sequentially sleeved on the outer side of the core pipe, and a plurality of hard insulation sections and a plurality of soft insulation sections arranged between the inner lining layer and the outer protective pipe, wherein the hard insulation sections and the soft insulation sections are wrapped on the outer side of the inner lining layer and arranged in a staggered manner along the length direction of the core pipe, and the hard insulation sections and the soft insulation sections are overlapped with each other by insulating materials; an integrated organic insulation layer is arranged on the inner side of the outer protective pipe, and the organic insulation layer is used to tightly wrap the hard insulation sections and the soft insulation sections inside the outer protective pipe together.

[0008] The hard insulation section and the soft insulation section provided in the technical solution are respectively composed of a composite of multiple layers of insulation materials, wherein the hard insulation section has the function of bearing the operating load of the heating network and taking into account insulation, the soft insulation section has a low thermal conductivity and is light in weight, and mainly utilizes the insulation performance for insulation to prevent heat loss, and the distance between the two hard insulation sections is calculated by the span; and the hard insulation section and the soft insulation section are staggered and overlapped by insulation materials, and the staggered and overlapped insulation materials refer to cutting the insulation layer materials into mutually matching inclined structures at the connection of the insulation layers, and overlapping them in layers; the staggered and overlapped here is equivalent to reserving expansion joints for the thermal expansion of the core tube, extending the heat transfer path, and effectively reducing heat loss; at the same time, the one-piece organic insulation layer arranged on the outside of the hard insulation section and the soft insulation section can effectively make the insulation pipe have good overall structural stability, simple structural design and production, strong economy, and convenient for industrial application.

[0009] Preferably, the inner lining layer is made of aluminum silicate needle-punched blanket, which has excellent thermal insulation and high temperature resistance; and an inner lining reflective layer is provided on the outer side of the inner lining layer, and the inner lining reflective layer is made of aluminum foil fiberglass cloth, and has the aluminum foil side facing the inner core tube, which can effectively reduce heat radiation and reduce heat loss.

[0010] Preferably, the hard insulation section includes at least one hard insulation layer and a hard reflective layer wrapped around the outside of the hard insulation layer. The material used for the hard insulation layer is calcium silicate insulation tiles, so that when the insulation pipe is installed, it can be installed on the pipe support through the hard insulation section of the insulation pipe. The spacing between two adjacent hard insulation sections is determined in advance according to the design conditions, and the hard insulation section is a special support structure for the intermittent prefabricated overhead insulation pipe. The hard insulation layer in this technical solution is made of calcium silicate insulation tiles as insulation material, and the density of calcium silicate insulation tiles is 200±20kg / m 3 , long-term temperature resistance is not less than 650℃, compressive strength is ≥0.7MPa, thermal conductivity satisfies: λ≤0.056w / (m·k)@25℃; the material used for the hard reflective layer in the technical scheme can be aluminum foil glass fiber cloth, and similarly, the aluminum foil side faces the inner core tube.

[0011] Preferably, the soft insulation section comprises at least one soft insulation layer and a soft reflective layer wrapped around the outside of the soft insulation layer, and the material of the soft insulation layer is aluminum silicate needle-punched blanket and / or glass wool. The density of the aluminum silicate needle-punched blanket in this technical solution is 128±10kg / m 3 The long-term temperature resistance is not less than 900℃, and the thermal conductivity at room temperature is λ≤0.044w / (m·k); the glass wool in this technical solution is ultra-fine glass wool, and its density is 48±5kg / m 3 , long-term temperature resistance is not less than 300°C, and the thermal conductivity at room temperature is λ≤0.041w / (m·k); the material used for the soft reflective layer in the technical solution is aluminum foil glass fiber cloth, and similarly, the aluminum foil side faces the inner core tube.

[0012] Preferably, the material of the soft insulation layer is determined according to the temperature of the medium in the core tube. When the temperature of the medium in the core tube is greater than 300°C, the material of the soft insulation layer is aluminum silicate needle-punched blanket; when the temperature of the medium in the core tube is less than or equal to 300°C, the material of the soft insulation layer is glass wool.

[0013] Preferably, the soft insulation section further comprises a jacket layer, which is cylindrical and made of metal and is wrapped around the outer side of the outermost soft reflective layer so that the outer diameter of the jacket layer is the same as the outer diameter of the hard insulation section.

[0014] Preferably, the jacket layer is a cylindrical structure made of tinplate, which is arranged at the outermost layer of the soft insulation section. The axial lap joints and radial lap joints along the core tube are anchored with rivets, and there is an overlap between the jacket layer and the hard insulation section, and the overlap length is not less than 5 cm. Therefore, the soft insulation section utilizes the jacket layer to have a certain structural rigidity, and can separate the foaming material from the soft insulation layer material during the foaming process of the organic insulation layer, so as to protect the soft material from the impact of polyurethane foaming, thereby ensuring the roundness and thickness of the soft insulation section.

[0015] Preferably, an annular support structure is evenly arranged on the outside of the hard insulation section and the soft insulation section, and the foaming material of the organic insulation layer is made of hard polyurethane foam; so that the annular support structure and the foaming material of the organic insulation layer are cast together in the outer protective tube. In this technical solution, the annular support structure is cut and processed from high-density polyurethane, and is cast together with the foaming material of the organic insulation layer, so that the entire insulation pipe has good overall structural strength and takes into account its insulation effect. The structural design is ingenious and reasonable, which can effectively ensure that the organic insulation layer is not eccentric and does not collapse.

[0016] Preferably, the outer protective pipe adopts a spiral air duct. In the present technical solution, the spiral air duct is made of metal sheets such as galvanized iron sheets, thin aluminum plates or stainless steel plates through mechanical biting. It has high dimensional accuracy, good structural rigidity, and the interface biting is tight and waterproof. It can effectively protect the internal insulation structure from interference from external forces and is not easy to deform and collapse, thereby greatly reducing the later maintenance costs of the pipeline network.

[0017] A method for manufacturing an intermittent prefabricated overhead insulated pipe comprises the following steps:

[0018] Step 1, surface treatment of the core tube to remove burrs and dust;

[0019] Step 2, wrapping the inner lining layer on the outer side of the core tube: the inner lining layer material is trapped on the outer surface of the core tube (1) so that two adjacent sections of the inner lining layer material are overlapped with staggered seams;

[0020] Step 3, staggeredly arranging the hard insulation sections and the soft insulation sections, and staggeredly overlapping the hard insulation sections and the soft insulation sections through insulation materials;

[0021] Step 4, set the outer protective tube: on the outside of the soft insulation section and the hard insulation section, set the annular support structure at intervals along the length direction of the core tube; use the threading sleeve equipment to set and fix the outer protective tube on the outside of the prefabricated insulation tube, fix the two ends of the outer protective tube with thermoplastic sleeves, and ensure that a space cavity is formed between the outer protective tube and the soft insulation section and the hard insulation section inside the outer protective tube;

[0022] Step 5, foaming the organic insulation layer: inject the foaming material for making the organic insulation layer into the space cavity formed between the outer protective tube and the soft insulation section and the hard insulation section inside it, and close the injection port after the injection is completed; after the foaming material is matured, the two ends of the insulation tube are surface treated to complete the production of the insulation tube.

[0023] More specifically, a method for manufacturing an intermittent prefabricated overhead insulated pipe comprises the following steps:

[0024] Step 1, surface treatment of the core tube to remove burrs and dust;

[0025] Step 2, wrapping the inner lining layer and the inner lining reflective layer on the outer side of the core tube in sequence: the inner lining layer material is trapped on the outer surface of the core tube so that two adjacent sections of the inner lining layer material are overlapped by staggered seams, and the inner lining reflective layer is wrapped on the outer side of the inner lining layer so that the side of the inner lining reflective layer with the reflective material faces the side of the core tube, and is bundled on the inner lining layer;

[0026] Step 3, making a hard insulation section: the hard insulation section includes at least one hard insulation layer and a hard reflective layer, the hard insulation layer is radially divided into a cylindrical shape consisting of at least two pieces of hard insulation layer material; the hard reflective layer is wrapped around the outside of the hard insulation layer and tied to the hard insulation layer;

[0027] Step 4, making a soft insulation section: the soft insulation section includes at least one soft insulation layer, a soft reflection layer and a jacket layer. The soft insulation layer is wrapped on the lining reflection layer between two adjacent hard insulation sections, the soft reflection layer is wrapped on the outside of each soft insulation layer, and the jacket layer is wrapped on the outside of the outermost soft reflection layer. The jacket layer is made of a metal tube, and the outer diameter of the jacket layer is ensured to be the same as the outer diameter of the hard protection section.

[0028] Step 5, set the outer protective tube: on the outside of the soft insulation section and the hard insulation section, set a group of annular support structures at intervals along the length direction of the core tube; use the threading sleeve equipment to set and fix the outer protective tube on the outside of the prefabricated insulation tube, fix the two ends of the outer protective tube with thermoplastic sleeves, and ensure that a space cavity is formed between the outer protective tube and the soft insulation section and the hard insulation section inside the outer protective tube;

[0029] Step 6, foaming the organic insulation layer: inject the foaming material for making the organic insulation layer into the space cavity formed between the outer protective tube and the soft insulation section and the hard insulation section inside it, and close the injection port after the injection is completed; after the foaming material is matured, perform surface treatment on both ends of the insulation tube to complete the production of the insulation tube.

[0030] Preferably, each insulation layer material in the above technical solution is wrapped by staggered overlap, the edge profile of the insulation material overlap is cut to ≤45°, and the width of the stacked overlap is not less than 5cm.

[0031] Preferably, in the above technical solution, various insulation materials in the soft insulation section and the hard insulation section and the soft reflective layer and the hard reflective layer are bundled in layers with steel strips, and the bundling spacing is not greater than 30 cm.

[0032] Preferably, the foaming material of the organic insulation layer is rigid polyurethane foam with a density of 60±5kg / m 3 , compressive strength ≥ 0.22MPa, thermal conductivity at room temperature meets: λ≤0.02w / (m·k)@25℃, and the use temperature of the organic insulation layer is not more than 120℃, specifically by adjusting the insulation thickness of the soft insulation section and the hard insulation section, so as to reduce the temperature to an acceptable range for the organic insulation layer. The extremely low thermal conductivity of the organic insulation layer plays a vital role in the insulation effect of the entire finished insulation pipe; at the same time, the organic insulation layer is cast later, which can tightly wrap the internal soft insulation section and the hard insulation section together, so that the entire insulation pipe is tightly fitted to ensure the overall structure of the insulation pipe is strong.

[0033] Preferably, during the foaming process of the organic thermal insulation layer, the temperature of the foaming material is controlled within the range of 25±2°C. This technical solution strictly controls the temperature of the foaming material of the organic thermal insulation layer. According to the inventors' findings, if the temperature of the foaming raw material is too low, the chemical reaction of the raw material is slow, and the foam body is formed and solidified for a long time, which affects the processing efficiency of the thermal insulation pipe; on the contrary, if the temperature is too high, the raw material reacts quickly, the foam body is formed and solidified for a short time, and the material liquid solidifies before it has time to flow in the casing, resulting in a local hollow shell. Therefore, the inventors have strictly controlled and analyzed in practice and found that in order to prepare polyurethane foam with excellent performance, the raw material temperature should be controlled within the range of 25±2°C.

[0034] As described above, the present invention has at least the following beneficial effects relative to the prior art:

[0035] 1. The heat-insulating pipe of the present invention is designed with a structure that combines hard insulation sections and soft insulation sections that are staggered along the length direction of the core pipe, so that the hard insulation sections of the heat-insulating pipe itself have good supporting strength, so that they are connected with the pipe support, providing a strong safety guarantee for the long-term operation of the thermal network, and being able to achieve the effect of bearing the operating load of the thermal network while taking into account the insulation function; at the same time, the soft insulation section has excellent insulation performance, low thermal conductivity, and light weight, which will significantly reduce the energy loss of the thermal network.

[0036] 2. The hard insulation section of the present invention is designed by combining at least one hard insulation layer and a hard reflective layer wrapped around the outside of the hard insulation layer. The hard insulation layer and the hard reflective layer are carefully designed with existing materials so that the hard insulation section can be used to bear the operating load of the heating network and take into account the insulation function; and the material is easy to obtain and has good economy. During on-site installation, the design of the hard insulation section can be effectively utilized to place it on the pipe support to play a good supporting role. The soft insulation section is avoided from the pipe support position, which effectively protects the soft insulation section.

[0037] 3. The soft insulation section of the present invention adopts a combination design of at least one soft insulation layer and a soft reflective layer and a jacket layer wrapped around the outside of the soft insulation layer. The material of the soft insulation layer is carefully selected according to the temperature of the medium in the core tube, and the insulation effect, material cost and material weight of the material are comprehensively considered. The arrangement of the reflective layers of each insulation material can effectively reduce heat radiation and reduce heat loss. In this way, the soft insulation section is ensured to have excellent insulation performance, good economy and light weight, which will significantly reduce the energy loss and production cost of the thermal pipe network.

[0038] 4. The present invention arranges a jacket layer on the outside of the soft insulation section, and the outer diameter of the jacket layer is the same as the outer diameter of the hard insulation section. If the jacket layer has a certain structural rigidity, the foaming material can be separated from the soft insulation layer material during the foaming process of the organic insulation layer to protect the soft material from the impact of polyurethane foaming, thereby ensuring the roundness and thickness of the soft insulation section.

[0039] 5. The present invention evenly arranges annular support structures outside the hard insulation section and the soft insulation section, and the annular support structures are cast together with the foaming material of the organic insulation layer in the outer protective tube, so that the entire insulation pipe has good overall structural strength while taking into account its insulation effect. The structural design is ingenious and reasonable, which can effectively ensure that the organic insulation layer is not eccentric and does not collapse.

[0040] 6. The organic insulation layer and the outer protective tube of the insulated pipe of the present invention make the overall structural design of the insulated pipe have good structural strength, and the organic insulation layer is an integrated structural design and is made of hard polyurethane foam, which has excellent insulation performance, so that the hard insulation section and the soft insulation section inside it are tightly wrapped together, having good structural strength and good insulation effect.

[0041] 7. The insulated pipe of the present invention has a simple manufacturing process, is easy to process, and the material is easily available, and has good economy; the insulated pipe produced by it has good structural strength and thermal insulation effect. It is applied in the field of prefabricated overhead steam transportation to achieve safety and stability of the entire pipeline network, high efficiency and energy saving, and has good application prospects and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present invention will be described by way of specific embodiments with reference to the accompanying drawings, in which

[0043] Figure 1 2 is a schematic diagram of the structure of the intermittent prefabricated overhead thermal insulation pipe according to an embodiment of the present invention;

[0044] Figure 2 is a schematic structural diagram of a hard insulation section in an embodiment of the present invention;

[0045] Figure 3 is a schematic structural diagram of a soft insulation section in an embodiment of the present invention;

[0046] Figure 4 is a schematic diagram of the arrangement of the annular support structure in an embodiment of the present invention;

[0047] Figure 5 Schematic diagram of the structure of the calcium silicate tile in the embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of the structure of calcium silicate tiles assembled in an embodiment of the present invention;

[0049] Figure 7 Schematic diagram of the intermittent prefabricated overhead thermal insulation pipe after being manufactured in an embodiment of the present invention;

[0050] Explanation of the accompanying drawings: 1-core tube; 2-inner lining layer; 21-inner lining reflective layer; 3-soft insulation layer; 31-soft reflective layer; 4-hard insulation layer; 40-calcium silicate insulation tile; 41-hard reflective layer; 5-organic insulation layer; 6-jacket layer; 7-annular support structure; 8-outer protective tube. DETAILED DESCRIPTION

[0051] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0052] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0053] The overall structure diagram of the embodiment is as follows Figure 1 As shown: This embodiment provides an intermittent prefabricated overhead insulated pipe, including a core tube 1, an inner lining layer 2 and an outer protective tube 8 which are sequentially sleeved on the outside of the core tube 1, and a plurality of hard insulation sections and a plurality of soft insulation sections arranged between the inner lining layer 2 and the outer protective tube 8. This embodiment takes the provision of two hard insulation sections and three soft insulation sections as an example; the hard insulation sections and the soft insulation sections are wrapped on the outside of the inner lining layer 2 and are arranged alternately along the length direction of the core tube 1. The length of each hard insulation section is about 1m, and the distance between the two hard insulation sections is calculated by the span; and the hard insulation sections and the soft insulation sections are staggered and overlapped by insulating materials; an integrated organic insulation layer 5 is arranged on the inner side of the outer protective tube 8, and the organic insulation layer 5 is used to tightly wrap the hard insulation sections and soft insulation sections inside it together.

[0054] Specifically, the insulating material used for the inner lining layer 2 of this embodiment is an aluminum silicate needle-punched blanket, which has excellent thermal insulation and high temperature resistance, and an inner lining reflective layer 21 is sleeved on the outer side of the inner lining layer 2. The material used for the inner lining reflective layer 21 is aluminum foil glass fiber cloth, and the aluminum foil side faces the inner core tube 1, which can effectively reduce heat radiation and reduce heat loss.

[0055] like Figure 2As shown, the hard insulation section includes at least one hard insulation layer 4 and a hard reflective layer 41 wrapped on the outside of the hard insulation layer 4. This embodiment takes the provision of a hard insulation section including two hard insulation layers 4 wrapped in sequence and a hard reflective layer 41 wrapped on the outside of each hard insulation layer 4 as an example. Specifically, the material used for the hard insulation layer 4 is calcium silicate insulation tile 40, so that when the insulation pipe is installed, it is installed on the pipe support through the hard insulation section of the insulation pipe, which plays a good supporting role. The soft insulation section avoids the position of the pipe support, which effectively protects the soft insulation section. The spacing between two adjacent hard insulation sections is determined in advance according to the design conditions, and the hard insulation section is a special support structure for the intermittent prefabricated overhead insulation pipe. The hard insulation layer 4 in this embodiment is made of calcium silicate insulation tile 40 as the insulation material, and the density of the calcium silicate insulation tile 40 is 200±20kg / m 3 , long-term temperature resistance is not less than 650°C, compressive strength is ≥0.7MPa, and thermal conductivity satisfies: λ≤0.056w / (m·k)@25°C; the material used for the hard reflective layer 41 in this embodiment can be aluminum foil glass fiber cloth, and similarly has an aluminum foil side facing the inner core tube 1; it is not limited to this, and of course other reflective materials in other prior arts can also be used, which should be included in the protection scope of the present invention.

[0056] like Figure 3 As shown in the figure, the soft insulation section includes at least one soft insulation layer 3 and a soft reflection layer 31 wrapped on the outside of the soft insulation layer 3. In this embodiment, the soft insulation section includes two soft insulation layers 3 wrapped in sequence and a soft reflection layer 31 wrapped on the outside of each soft insulation layer 3. For example, the material of the soft insulation layer 3 is aluminum silicate needle-punched blanket and / or glass wool. Specifically, the material of the soft insulation layer 3 is determined according to the temperature of the medium in the core tube 1. When the temperature of the medium in the core tube 1 is greater than 300°C, the material of the soft insulation layer 3 is silicon. Aluminum silicate needle punched blanket; when the temperature of the medium in the core tube 1 is less than or equal to 300°C, the material used for the soft insulation layer 3 is glass wool. This embodiment takes the insulation material used for the soft insulation layer 3 as high-temperature resistant glass wool as an example. The thickness of each layer of high-temperature resistant glass wool is about 40mm. A soft reflective layer 31 is wrapped on the outside of each layer of glass wool. As a preferred embodiment of this embodiment, the material of the soft reflective layer 31 is aluminum foil glass fiber cloth. Similarly, the aluminum foil side faces the inner core tube 1 to reduce heat radiation and heat loss. In order to make the soft insulation section have excellent insulation performance, the density of the aluminum silicate needle punched blanket in this embodiment is 128±10kg / m 3 , the long-term use temperature resistance is not less than 900℃, and the thermal conductivity at room temperature is λ≤0.044w / (m·k); the density of the glass wool in this embodiment is 48±5kg / m 3 , long-term temperature resistance is not less than 300℃, and the thermal conductivity at room temperature is λ≤0.041w / (m·k).

[0057] As a preference of this embodiment, the soft insulation section provided in this embodiment also includes a jacket layer 6, which is cylindrical and made of a metal material with a certain rigidity. Preferably, the jacket layer 6 is a cylindrical structure rolled from tinplate, which is arranged at the outermost layer of the soft insulation section, and the axial lap seams and radial lap seams along the core tube 1 are anchored with rivets, and there is a staggered overlap between the jacket layer 6 and the outermost hard reflective layer 41 of the hard insulation section, and the staggered overlap length is not less than 5 cm; thus, the soft insulation section utilizes the jacket layer 6 with a certain structural rigidity, and can separate the foaming material from the soft insulation layer 3 material during the foaming process of the organic insulation layer 5, so as to protect the soft material from the impact of polyurethane foaming, thereby ensuring the roundness and thickness of the soft insulation section.

[0058] like Figure 4 As shown, an annular support structure 7 is evenly arranged on the outside of the hard insulation section and the soft insulation section. The annular support structure 7 used in this embodiment is cut and processed by high-density polyurethane, and is radially wrapped around the hard reflective layer 41 of the outermost layer of the hard insulation section for support and fixation, and is radially wrapped around the jacket layer 6 of the outermost layer of the soft insulation section for support and fixation; and the annular support structure 7 is located in the space cavity formed between the outer protective tube 8 and the soft insulation section and the hard insulation section on its inner side. During the foaming process of the organic insulation layer 5, the annular support structure 7 and the foaming material of the organic insulation layer 5 are cast together in the outer protective tube 8, so that the entire insulation tube has a good overall structural strength and takes into account its insulation effect. The structural design is ingenious and reasonable, which can effectively ensure that the organic insulation layer 5 is not eccentric and does not collapse. Preferably, the foaming material of the organic insulation layer 5 is made of hard polyurethane foam, which can tightly wrap the internal insulation structure, so that the prefabricated insulation tube has a certain overall strength.

[0059] Furthermore, the outer protective tube 8 adopted in this embodiment specifically adopts a spiral air duct, which is formed by mechanically biting metal sheets such as galvanized iron sheets, thin aluminum plates or stainless steel plates. It has high dimensional accuracy, good structural rigidity, and the interface bite is tight and waterproof. It can effectively protect the internal insulation structure from interference from external forces, and is not easy to deform and collapse, thereby greatly reducing the later maintenance costs of the pipeline network; such an insulated pipe organic insulation layer 5 and outer protective tube 8 make the overall structural design of the insulated pipe have good structural strength, and the organic insulation layer 5 is an integrated structural design and is made of hard polyurethane foam, with excellent insulation performance.

[0060] on the other hand, Figure 7 A schematic diagram of a discontinuous prefabricated overhead insulated pipe after manufacture according to an embodiment of the present invention is shown. According to the present invention, this embodiment also provides a method for manufacturing a discontinuous prefabricated overhead insulated pipe, and the manufacturing method specifically comprises the following steps:

[0061] Step 1, performing surface treatment on the core tube 1 to remove burrs and dust;

[0062] Step 2, wrap the inner lining layer 2 and the inner lining reflective layer 21 on the outer side of the core tube 1 in sequence: cut the aluminum silicate needle-punched blanket of the inner lining layer 2 material, and tie it on the outer surface of the core tube 1 with a galvanized steel belt, specifically tie a steel belt every 25 cm, so that the two adjacent sections of the inner lining layer 2 material are wrapped with staggered overlaps, and the edge profile of the overlap is cut to 45°, and the width of the laminated overlap is not less than 5 cm; wrap the inner lining reflective layer 21 with aluminum foil and glass fiber cloth on the outer side of the inner lining layer 2, so that the side of the inner lining reflective layer 21 with the reflective material faces the side of the core tube 1, and tie it to the inner lining layer 2 with a galvanized steel belt, and the tying requirements of the inner lining reflective layer 21 are the same as the tying requirements of the inner lining layer 2;

[0063] Step 3, making a hard insulation section: the hard insulation section includes two layers of hard insulation layer 4 and hard reflection layer 41, and the hard insulation layer 4 is radially divided into a cylindrical shape composed of at least two pieces of hard insulation layer 4 material spliced ​​together, such as Figure 5 and Figure 6 As shown, in this embodiment, a hard insulation layer 4 is provided which is radially divided into three cylindrical pieces of calcium silicate insulation tiles 40, and an aluminum foil fiberglass cloth of a hard reflective layer 41 is wrapped on the outside of the hard insulation layer 4, and is tied to the hard insulation layer 4 with a galvanized steel belt, and the tying interval is not greater than 25 cm, and the hard reflective layer 41 covers the lap joints of the calcium silicate insulation tiles 40; and the axial lap joints of the hard insulation layer 4 material along the core tube 1 and the radial lap joints along the core tube 1 are staggered with the lap joints of the inner lining reflective layer 21 material and the outer lap joints of the hard reflective layer 41, and the length of each section of the hard insulation layer 4 is about 1 m;

[0064] Step 4, making a soft insulation section: the soft insulation section includes two layers of soft insulation layers 3 and a soft reflective layer 31 and a jacket layer 6, the soft insulation layer 3 is wrapped with glass wool on the lining reflective layer 21 between two adjacent hard insulation sections, the soft reflective layer 31 is wrapped with aluminum foil and glass fiber cloth on the outside of each soft insulation layer 3, and the jacket layer 6 is wrapped on the outside of the outermost soft reflective layer 31, the jacket layer 6 is made of a metal tube rolled from tinplate, and the outer diameter of the jacket layer 6 is ensured to be the same as the outer diameter of the hard protection section;

[0065] Step 5, set the outer protective tube 8: on the outside of the soft insulation section and the hard insulation section, set a group of annular support structures 7 at a distance of 1m along the length direction of the core tube 1; use the threading sleeve equipment to set and fix the outer protective tube 8 on the outside of the prefabricated insulation tube, fix the two ends of the outer protective tube 8 with thermoplastic sleeves, and ensure that a space cavity is formed between the outer protective tube 8 and the soft insulation section and the hard insulation section inside it;

[0066] Step 6, foaming the organic insulation layer 5: inject the foaming material for making the organic insulation layer 5 from the middle of the length direction of the outer protective tube 8 into the space cavity formed between the outer protective tube 8 and the soft insulation section and the hard insulation section inside it, and control the foam density to 60±5kg / m 3 ; After the injection is completed, the injection port will be closed; wait for 30min to 60min of maturation, and after the foaming material is matured, the surface treatment will be carried out on both ends of the insulation pipe, and the production of the insulation pipe will be completed. After the finished insulation pipe is inspected and qualified, it will be sent to the warehouse for storage.

[0067] In this embodiment, the axial overlap seams of the insulation materials along the core tube 1 should avoid the vertical plane where the central axis of the core tube 1 is located as the reference plane, and the arrangement space within the range of 30° on both sides of the reference plane above the core tube 1.

[0068] As a preferred embodiment of the manufacturing method of this embodiment, the foaming material of the organic insulation layer 5 selected in this embodiment is a hard polyurethane foam with a density of 60±5kg / m 3 , compressive strength ≥ 0.22MPa, thermal conductivity at room temperature meets: λ ≤ 0.02w / (m·k)@25℃; the extremely low thermal conductivity of the organic insulation layer 5 plays a vital role in the insulation effect of the entire finished insulation pipe; at the same time, the organic insulation layer 5 is cast later, which can tightly wrap the internal soft insulation section and the hard insulation section together, so that the entire insulation pipe is tightly fitted to ensure the overall structure of the insulation pipe is strong.

[0069] Furthermore, the use temperature of the organic thermal insulation layer 5 is not greater than 120° C., and the temperature is reduced to an acceptable range for the organic thermal insulation layer 5 by adjusting the thermal insulation thickness of the soft thermal insulation section and the hard thermal insulation section.

[0070] Furthermore, during the foaming process of the organic thermal insulation layer 5, the temperature of the foaming material is controlled within the range of 25±2°C. In this embodiment, the temperature of the foaming material of the organic thermal insulation layer 5 is strictly controlled. According to the inventors' findings, if the temperature of the foaming raw material is too low, the chemical reaction of the raw material is slow, and the foam body is formed and solidified for a long time, which affects the processing efficiency of the thermal insulation pipe; on the contrary, if the temperature is too high, the raw material reaction speed is fast, the foam body is formed and solidified for a short time, and the material liquid solidifies before it has time to flow in the sleeve, resulting in a local hollow shell. Therefore, the inventors have strictly controlled and analyzed in practice and found that in order to prepare a polyurethane foam with excellent performance, the raw material temperature should be controlled within the range of 25±2°C.

[0071] To sum up, the intermittent prefabricated overhead insulated pipe of the present invention has a simple manufacturing process, convenient processing and low manufacturing cost; the prepared insulated pipe utilizes the hard insulation section of the insulation pipe itself to have good supporting strength, which can provide strong safety guarantee for the long-term operation of the thermal network, and the introduced jacket layer 6 can effectively protect the internal soft insulation section material from the impact of foaming, thereby ensuring the roundness of the soft insulation layer 3; at the same time, the soft insulation section has excellent insulation performance, low thermal conductivity and light weight, which will significantly reduce the energy loss of the thermal network, so as to achieve the effect of bearing the operating load of the heat network and taking into account the insulation function, and apply it in the field of prefabricated overhead steam transportation to achieve safety, stability, high efficiency and energy saving of the entire pipeline network, with good application prospects and promotion and use value, and is suitable for promotion and application.

[0072] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A method for manufacturing an intermittent prefabricated overhead insulated pipe, characterized in that: The discontinuous prefabricated overhead thermal insulation pipe comprises a core pipe (1), an inner lining layer (2) and an outer protective pipe (8) which are sequentially sleeved on the outer side of the core pipe (1), and a plurality of hard thermal insulation sections and a plurality of soft thermal insulation sections arranged between the inner lining layer and the outer protective pipe, wherein the hard thermal insulation sections and the soft thermal insulation sections are wrapped around the outer side of the inner lining layer (2) and arranged in a staggered manner along the length direction of the core pipe (1), and the hard thermal insulation sections and the soft thermal insulation sections are overlapped by thermal insulation materials; an organic thermal insulation layer (5) in an integrated manner is arranged on the inner side of the outer protective pipe (8), and the organic thermal insulation layer (5) is used to tightly wrap the hard thermal insulation sections and the soft thermal insulation sections inside the organic thermal insulation layer together; the manufacturing method of the discontinuous prefabricated overhead thermal insulation pipe comprises the following steps: Step 1, performing surface treatment on the core tube (1) to remove burrs and dust; Step 2, wrapping the inner lining layer (2) on the outer side of the core tube (1): trapping the inner lining layer material on the outer surface of the core tube (1) so that two adjacent sections of the inner lining layer material are overlapped with staggered seams; Step 3, staggeredly arranging the hard insulation sections and the soft insulation sections, and staggeredly overlapping the hard insulation sections and the soft insulation sections through insulation materials; Step 4, sleeve the outer protective tube (8): on the outside of the soft insulation section and the hard insulation section, an annular support structure (7) is arranged at intervals along the length direction of the core tube; the outer protective tube (8) is sleeved and fixed on the outside of the prefabricated insulation tube by using a threading sleeve device, and the two ends of the outer protective tube are fixed with a thermoplastic sleeve, and a space cavity is formed between the outer protective tube and the soft insulation section and the hard insulation section inside the outer protective tube; Step 5, foaming the organic insulation layer: injecting the foaming material for making the organic insulation layer (5) into the space cavity formed between the outer protective tube and the soft insulation section and the hard insulation section inside it, and closing the injection port after the injection is completed; after the foaming material is matured, surface treatment is performed on both ends of the insulation tube, and the insulation tube is completed.

2. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: The material used for the inner lining layer (2) is an aluminum silicate needle-punched blanket; and an inner lining reflection layer (21) is sleeved on the outer side of the inner lining layer (2).

3. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: The hard insulation section comprises at least one hard insulation layer (4) and a hard reflection layer (41) wrapped around the outside of the hard insulation layer. The hard insulation layer (4) is made of calcium silicate insulation tiles, so that when the insulation pipe is installed, it can be installed on the pipe support through the hard insulation section of the insulation pipe.

4. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: The soft thermal insulation section comprises at least one soft thermal insulation layer (3) and a soft reflective layer (31) wrapped around the outside of the soft thermal insulation layer; the material used for the soft thermal insulation layer (3) is aluminum silicate needle-punched blanket and / or glass wool.

5. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 4, characterized in that: The material of the soft thermal insulation layer (3) is determined according to the temperature of the medium in the core tube. When the temperature of the medium in the core tube is greater than 300° C., the material used by the soft thermal insulation layer (3) is an aluminum silicate needle-punched blanket; when the temperature of the medium in the core tube is less than or equal to 300° C., the material used by the soft thermal insulation layer (3) is glass wool.

6. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 4, characterized in that: The soft insulation section further comprises a jacket layer (6), which is cylindrical and made of metal, so that the outer diameter of the jacket layer (6) is the same as the outer diameter of the hard insulation section.

7. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: An annular support structure (7) is evenly arranged outside the hard insulation section and the soft insulation section; the foaming material of the organic insulation layer (5) is made of hard polyurethane foam; so that the annular support structure (7) and the foaming material of the organic insulation layer (5) are cast together in the outer protective tube.

8. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: The foaming material of the organic heat insulating layer (5) is a rigid polyurethane foam with a density of 60±5 kg / m 3 , compressive strength ≥ 0.22 MPa, thermal conductivity at room temperature satisfies: λ ≤ 0.02w / (m·k)@25°C, and the operating temperature of the organic insulation layer (5) is not greater than 120°C.

9. The method for manufacturing the intermittent prefabricated overhead insulated pipe according to claim 1, characterized in that: During the foaming process of the organic heat-insulating layer (5), the temperature of the foaming material is controlled within the range of 25±2°C.

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