A pipe repair hose and method of making the same

Abstract

The application discloses a pipeline repairing hose and a preparation method thereof, relates to the technical field of pipeline repairing material preparation, and effectively avoids asynchronous cooling and shrinkage of melts of various layers, guarantees uniform wall thickness of the hose, no deviation between layers and high roundness of the finished product through co-extrusion of an inner layer and an inner hot melt adhesive layer, weaving of a reinforcing layer, co-extrusion of an outer hot melt adhesive and an outer layer and finally overmolding. The step-by-step process has relatively low requirements on equipment precision, reduces the production difficulty of large-diameter products, improves the yield and the stability of continuous production. Through independent setting of the inner hot melt adhesive layer and the outer hot melt adhesive layer, the interlayer bonding strength is improved, and delamination, bulging or peeling during long-term use is avoided. Through the step-by-step continuous composite molding process, the interlayer bonding reliability of the hose is improved under the premise of guaranteeing the production quality and the production efficiency of the hose, the process route for preparing the hose is enriched, and the practical application range of the hose is further widened.

Description

Technical Field

[0001] This invention relates to the field of pipeline repair material preparation technology, and in particular to a pipeline repair hose and its preparation method. Background Technology

[0002] The existing method for manufacturing hoses involves simultaneously extruding the inner and outer coatings in one step using a set of combined molds after the reinforcing layer is braided. The shortcomings of this existing technology are: Firstly, the cooling time of the melt in each layer of the one-piece molding process is not synchronized, resulting in uneven wall thickness, interlayer misalignment, and poor roundness of the finished product. Moreover, one-piece molding requires extremely high equipment precision, making it difficult to produce large-diameter hoses, resulting in low yield and insufficient stability in continuous production. Secondly, the inner and outer layers of the hose are in direct contact with the dry fiber reinforcement layer, relying on the melt pressure during extrusion in the manufacturing process to penetrate into the fiber gaps and form a physical-mechanical interlock. Due to the low surface energy of the fibers, the molten inner and outer layers cannot completely wet the fiber bundle, resulting in low interlayer bonding strength and interlayer peel strength of the hose. Under long-term operating conditions, delamination, bulging, or peeling are prone to occur, resulting in poor dimensional stability of the hose. Summary of the Invention

[0003] This invention provides a pipe repair hose and its preparation method to solve the problems of uneven wall thickness, interlayer misalignment, and poor roundness of finished products in existing hoses; high production difficulty, low yield, and insufficient stability of continuous production of large-diameter hoses; and low interlayer bonding strength and interlayer peel strength between hose layers, which easily lead to delamination, bulging, or peeling under long-term operating conditions, resulting in poor dimensional stability of the hose.

[0004] In a first aspect, the present invention provides a method for preparing a pipe repair hose, the method comprising: Step 100: Using two co-extrusion machines, the raw materials for the inner layer and the inner hot melt adhesive layer of the pipe repair hose are simultaneously extruded into the first co-extrusion mold for molding, and then sizing is performed to obtain the inner layer and the inner hot melt adhesive layer of the pipe repair hose. Step 200: Heat the inner hot melt adhesive layer to obtain an inner hot melt adhesive layer in a molten or semi-molten state. Step 300: Weaving is performed on the outer side of the inner hot melt adhesive layer in the molten or semi-molten state to obtain the reinforcing layer of the pipe repair hose; Step 400: Using two co-extrusion machines, the raw materials for the outer hot melt adhesive layer and the outer layer of the pipe repair hose are simultaneously extruded into the second co-extrusion die for molding, and then sizing is performed to obtain the outer hot melt adhesive layer and the outer layer of the pipe repair hose. Step 500: The outer hot melt adhesive layer and the outer layer are wrapped around the outside of the reinforcing layer, and then a cooling treatment is performed to obtain the pipe repair hose.

[0005] In a second aspect, the present invention provides a pipe repair hose, which is prepared using the pipe repair hose preparation method described in the first aspect.

[0006] The aforementioned pipe repair hose and its manufacturing method, by first co-extrude and sizing the inner layer and inner hot melt adhesive layer, then braiding the reinforcing layer, then co-extrudeing the outer hot melt adhesive and outer layer, and finally coating and molding, effectively avoids asynchronous cooling and shrinkage of the melts in each layer, ensuring uniform hose wall thickness, no interlayer misalignment, and high roundness of the finished product, significantly improving the interlayer positioning accuracy of the hose. This step-by-step process has relatively low requirements for equipment precision, reducing the production difficulty of large-diameter products and improving yield and continuous production stability. By independently setting the inner hot melt adhesive layer and heating and activating it before braiding, the hot melt adhesive is in a molten or semi-molten state, which can fully wet the inter-bundles and surface of the fiber reinforcing layer, forming a strong chemical or physical bonding interface. Combined with the co-extrusion coating of the outer hot melt adhesive layer, the interlayer bonding strength and interlayer peel strength between the inner and outer layers and the reinforcing layer are significantly improved, avoiding delamination, bulging or peeling during long-term use, and significantly improving the overall dimensional stability and service reliability of the hose. Compared with existing technologies, this invention improves the reliability of interlayer bonding of hoses by using a step-by-step continuous composite molding process, while ensuring the production quality and efficiency of the hoses. This not only enriches the process routes for hose manufacturing, but also further broadens the practical application range of hoses. Attached Figure Description

[0007] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0008] Figure 1 This is a flowchart of the preparation method of the pipe repair hose in Embodiment 1 of the present invention; Figure 2 These are schematic diagrams of the cross-section and longitudinal section of the pipe repair hose in Embodiment 10 of the present invention. Detailed Implementation

[0009] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0010] In Example 1, as Figure 1 As shown, this embodiment provides a method for preparing a pipe repair hose, the method comprising: Step 100: Using two co-extrusion machines, the raw materials for the inner layer and the inner hot melt adhesive layer of the pipe repair hose are simultaneously extruded into the first co-extrusion mold for molding, and then sizing is performed to obtain the inner layer and the inner hot melt adhesive layer of the pipe repair hose. The term "pipeline repair hose" refers to a composite hose used in trenchless pipeline lining repair. Two co-extrusion machines refer to two independent extrusion units, one for extruding the raw materials for the inner layer and the other for the inner hot melt adhesive layer. The inner layer is the innermost layer of the pipeline repair hose, in direct contact with the transported medium (e.g., hot water, oil, or gas). Its main functions include: transporting the fluid medium, providing sealing, leak prevention, and resistance to the medium, and withstanding the temperature, pressure, and potential chemical corrosion of the transported medium. The inner hot melt adhesive layer is an independent hot melt adhesive bonding layer structure located between the inner layer and the reinforcing layer of the pipeline repair hose. Its main functions include: improving the bonding performance between the inner layer and the reinforcing layer, increasing interlayer bonding strength, preventing interlayer delamination or structural instability under high temperature, thermal cycling, or long-term operating conditions, and improving the overall structural stability and long-term thermal stability of the hose. The first co-extrusion die is a combination die specifically used to composite the inner layer and the inner hot melt adhesive layer of the pipeline repair hose. Molding process refers to the operation in which the molten inner layer raw material and the molten inner hot melt adhesive layer raw material flow, converge, and are shaped into a continuous tubular composite preform of the inner layer and inner hot melt adhesive layer within the first co-extrusion die. Sizing process refers to the operation in which the dimensions of the continuous tubular composite preform of the inner layer and inner hot melt adhesive layer are sized.

[0011] Step 200: Heat the inner hot melt adhesive layer to obtain an inner hot melt adhesive layer in a molten or semi-molten state. Among them, heat treatment refers to the operation process of externally heating the inner hot melt adhesive layer after sizing. The molten state or semi-molten state refers to the physical state of the hot melt adhesive layer when it is heated to above its melting point or near its softening point, exhibiting good fluidity and wettability.

[0012] Step 300: Weaving is performed on the outer side of the inner hot melt adhesive layer in the molten or semi-molten state to obtain the reinforcing layer of the pipe repair hose; The braiding process refers to the operation of forming a continuous tubular fabric structure on the outside of the inner hot melt adhesive layer by interlacing the fiber yarns through warp and weft yarns. The reinforcing layer is the pressure-bearing layer structure located between the inner and outer hot melt adhesive layers of the pipe repair hose. Its main functions include: providing circumferential pressure resistance and axial dimensional stability, preventing radial expansion of the hose's inner layer under pressure or high temperature conditions, and ensuring the dimensional stability of the hose under high-temperature operating conditions.

[0013] Step 400: Using two co-extrusion machines, the raw materials for the outer hot melt adhesive layer and the outer layer of the pipe repair hose are simultaneously extruded into the second co-extrusion die for molding, and then sizing is performed to obtain the outer hot melt adhesive layer and the outer layer of the pipe repair hose. The outer hot melt adhesive layer refers to the independent hot melt adhesive bonding layer structure located between the outer layer and the reinforcing layer of the pipe repair hose. Its main functions include: improving the bonding performance between the outer layer and the reinforcing layer, increasing the interlayer bond strength, preventing interlayer delamination or structural instability of the hose under high temperature, thermal cycling, or long-term operation conditions, and improving the overall structural stability and long-term thermal stability of the hose. The outer layer refers to the outermost layer structure of the pipe repair hose. Its main functions include: protecting the intermediate reinforcing layer from external damage, and improving the hose's wear resistance, scratch resistance, and overall structural integrity during insertion, pulling, winding, bending, construction, and transportation. The second co-extrusion die is a combination die specifically used to composite the outer layer and the outer hot melt adhesive layer of the pipe repair hose.

[0014] Step 500: The outer hot melt adhesive layer and the outer layer are wrapped around the outside of the reinforcing layer, and then a cooling treatment is performed to obtain the pipe repair hose.

[0015] Here, "coating" refers to the process of continuously and uniformly bonding the outer hot melt adhesive layer to one side of the outer hot melt adhesive layer in the outer composite preform and wrapping it around the outer surface of the reinforcing layer. "Cooling treatment" refers to the process of cooling and curing the outer hot melt adhesive layer and the composite hose formed after the outer coating (e.g., natural cooling, cooling water tank, or spray box).

[0016] The method for manufacturing the pipe repair hose in this embodiment involves first co-extruded and sizing the inner layer and the inner hot melt adhesive layer, then braiding the reinforcing layer, followed by co-extruded the outer hot melt adhesive and the outer layer, and finally overmolding. This effectively avoids asynchronous cooling and shrinkage of the melts in each layer, ensuring uniform hose wall thickness, no interlayer misalignment, and high roundness of the finished product, significantly improving the interlayer positioning accuracy of the hose. This step-by-step process has relatively low requirements for equipment precision, reducing the difficulty of producing large-diameter products and improving yield and continuous production stability. By independently setting the inner hot melt adhesive layer and heating and activating it before braiding, the hot melt adhesive is in a molten or semi-molten state, which can fully wet the inter-bundles and surface of the fiber reinforcing layer, forming a strong chemical or physical bonding interface. Combined with the co-extrusion overmolding of the outer hot melt adhesive layer, the interlayer bonding strength and interlayer peel strength between the inner and outer layers and the reinforcing layer are significantly improved, avoiding delamination, bulging, or peeling during long-term use, and significantly improving the overall dimensional stability and service reliability of the hose. By using a step-by-step continuous composite molding process, the reliability of interlayer bonding in hoses is improved while ensuring production quality and efficiency. This not only enriches the process routes for hose manufacturing but also further broadens the practical application range of hoses.

[0017] In Example 2, in step 100, the barrel temperature of the co-extruder forming the inner layer is in the range of 140℃-220℃, the die temperature of the co-extruder forming the inner layer is in the range of 190℃-230℃, and the melt temperature of the inner layer forming the inner layer is in the range of 170℃-210℃.

[0018] Here, barrel temperature refers to the temperature at which the raw material for the inner layer is heated and plasticized within the barrel (the heated cylinder containing the screw) of the co-extruder that forms the inner layer. Die temperature refers to the temperature at the outlet (material extrusion port) of the co-extruder that forms the inner layer. Melt temperature refers to the actual measured temperature of the molten raw material for the inner layer within the range from the co-extruder die outlet to before entering the sizing device.

[0019] In this embodiment, the raw material of the inner layer is heated and plasticized in the barrel of the co-extruder that forms the inner layer to obtain the raw material of the inner layer in a molten state, and then extruded into the first co-extrusion die through the die head.

[0020] In this embodiment, preferably, the barrel temperature range of the co-extruder forming the inner layer is 140℃-220℃, the die temperature range of the co-extruder forming the inner layer is 190℃-230℃, and the melt temperature range of the inner layer is 170℃-210℃.

[0021] The method for manufacturing the pipe repair hose in this embodiment optimizes the barrel temperature, die temperature, and melt temperature of the co-extruder for the inner layer, effectively ensuring the quality of the inner layer molding while retaining the material's excellent heat resistance and creep resistance. A reasonable temperature range ensures that the inner layer material is fully plasticized and uniformly melted within the co-extruder, avoiding poor plasticization or melt fracture due to excessively low temperatures, and preventing thermal degradation or decomposition of bubbles due to excessively high temperatures. Simultaneously, a stable melt temperature ensures that the inner layer melt maintains matching fluidity with the inner hot melt adhesive layer after entering the first co-extrusion die, facilitating uniform merging of the two layers within the die and reducing interfacial stress. This results in a composite tube blank with a consistent wall thickness and a smooth surface, consisting of an inner layer and an inner hot melt adhesive layer. Combined with subsequent sizing treatment, this significantly improves the roundness and dimensional stability of the composite tube blank, increasing the overall yield of the hose production.

[0022] In Example 3, in step 100, the barrel temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 180℃-220℃, the die temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 200℃-240℃, and the screw speed of the co-extruder forming the inner hot melt adhesive layer is in the range of 10r / min-25r / min.

[0023] In this embodiment, preferably, the barrel temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 180℃-220℃, the die temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 200℃-240℃, and the screw speed of the co-extruder forming the inner hot melt adhesive layer is in the range of 10r / min-25r / min.

[0024] In this embodiment, the raw material of the inner hot melt adhesive layer is heated and plasticized in the barrel of the co-extruder that forms the inner hot melt adhesive layer to obtain the raw material of the inner hot melt adhesive layer in a molten state, and then extruded into the first co-extrusion die through the die head.

[0025] The method for preparing the pipe repair hose in this embodiment optimizes the design of the barrel temperature, die temperature, and screw speed of the co-extruder forming the inner hot melt adhesive layer. This ensures that the raw material for the inner hot melt adhesive layer is fully plasticized and melted within the co-extruder, resulting in moderate and stable melt flow. This temperature design effectively matches the temperature of the inner melt layer, ensuring uniform co-extrusion and a smooth interface transition. The temperature design avoids insufficient plasticization or decreased adhesive activity due to low temperatures, while also preventing aging and failure of the hot melt adhesive caused by excessively high temperatures. The matched screw speed enables continuous and uniform material output, ensuring that the flow of the hot melt adhesive matches that of the inner melt layer. This results in a tight bond between the two composite layers, uniform forming thickness, and effectively guarantees the adhesive performance of the hot melt adhesive layer. This lays the foundation for subsequent activation and impregnation of the fiber reinforcement layer, enhancing the overall interlayer bonding strength.

[0026] In Example 4, in step 100, the sizing process is performed using a vacuum sizing chamber. The vacuum degree of the vacuum sizing chamber is in the range of 0.005 MPa to 0.05 MPa, the sizing time is in the range of 5 s to 30 s, and the sizing temperature is in the range of 15 ℃ to 20 ℃.

[0027] Among them, vacuum degree refers to the negative pressure parameter inside the vacuum sizing box relative to atmospheric pressure during the sizing process.

[0028] In this embodiment, preferably, the sizing process is performed using a vacuum sizing chamber. The vacuum degree of the vacuum sizing chamber is in the range of 0.005 MPa to 0.05 MPa, the sizing time is in the range of 5 s to 30 s, and the sizing temperature is in the range of 15℃ to 20℃.

[0029] The method for preparing the pipe repair hose in this embodiment employs a vacuum sizing chamber and coordinates the design of vacuum degree, sizing time, and sizing temperature. Relying on negative pressure adsorption, the composite pipe blank of the inner layer and the inner hot melt adhesive layer is rapidly shaped, ensuring the roundness and wall thickness uniformity of the composite pipe blank. This parameter combination avoids insufficient shaping or large dimensional deviations caused by excessively low vacuum or insufficient sizing time, and also prevents deformation or surface depressions of the composite pipe blank caused by excessively high vacuum. A suitable low-temperature environment accelerates the cooling and solidification of the melt, stabilizes the dimensions of the composite pipe blank, and improves the dimensional accuracy and forming quality of the composite pipe blank.

[0030] In Example 5, in step 200, the heating treatment is performed using an oven, the temperature of which is in the range of 120℃-180℃, the heating time is in the range of 10s-30s, and the heating temperature is in the range of 80℃-120℃.

[0031] In this embodiment, preferably, the heating treatment is performed using an oven, with the oven temperature ranging from 120℃ to 180℃, the heating time ranging from 10s to 30s, and the heating temperature ranging from 80℃ to 120℃.

[0032] The method for preparing the pipe repair hose in this embodiment utilizes an oven to heat the inner hot melt adhesive layer. By precisely controlling the oven temperature, heating time, and the adhesive layer's temperature, the method rapidly activates the inner hot melt adhesive layer, transforming it into a molten or semi-molten state without damaging the structure and basic properties of the composite tube blank containing the inner and inner hot melt adhesive layers. This parameter combination avoids weak activation and insufficient wetting and bonding performance of the hot melt adhesive due to excessively low heating temperature or insufficient heating time, making it difficult to bond tightly with the reinforcing layer. It also avoids high-temperature aging failure of the hot melt adhesive and thermal deformation of the inner layer caused by excessively high heating temperature or prolonged heating time. Uniform and moderate heating improves the fluidity and surface wettability of the hot melt adhesive, facilitating its full penetration into the fiber gaps of the reinforcing layer, significantly improving interlayer bonding strength, preventing delamination, bulging, or peeling of the hose under long-term operating conditions, and enhancing the overall structural stability and long-term service life of the hose.

[0033] In Example 6, in step 300, the weaving process is a weaving operation using a circular loom. The warp and weft yarn specifications of the circular loom are both 44000D, the weft yarn density ranges from 15×2 yarns / 10cm to 20×2 yarns / 10cm, the total number of warp yarns ranges from 700 to 900, and the weaving structure is a twill weave structure.

[0034] A circular loom is a specialized textile machine used to weave the raw materials of the reinforcing layer into a continuous cylindrical fabric. Warp yarn specification refers to the thickness of the yarn arranged axially (longitudinally) along the pipe repair hose during the weaving process, measured in denier (D). Weft yarn specification refers to the thickness of the yarn that interweaves circumferentially (transversely) along the pipe repair hose during the weaving process, also measured in denier (D). Weft density is a measure of the number of weft yarns per unit length. Total warp count refers to the total number of warp yarns in the circular loom. Weaving structure refers to the interlacing arrangement of the warp and weft yarns in a circular loom. Twill weave structure refers to a fabric weaving method in which the weft yarns of a circular loom cross multiple warp yarns at a certain step length to form a diagonal texture.

[0035] In this embodiment, preferably, the weaving process is carried out using a circular loom. The warp and weft yarn specifications of the circular loom are both 44000D, the weft yarn density ranges from 15×2 yarns / 10cm to 20×2 yarns / 10cm (15-20 sets of weft yarns per 10cm length, with 2 yarns per set), the total number of warp yarns ranges from 700 to 900, and the weaving structure is a twill weave structure.

[0036] The method for manufacturing the pipe repair hose in this embodiment employs a circular loom, with carefully designed matching of warp and weft yarn specifications, weft density, total warp count, and braiding structure. The high yarn density and reasonable fabric arrangement provide the braided layer with excellent circumferential pressure resistance and structural strength, preventing radial deformation of the pipe repair hose under pressure or high temperature. The twill weave structure evenly distributes the load, improving the overall toughness and tensile strength of the fabric while maintaining good flexibility, making it suitable for hose winding, traction, and complex construction conditions. Simultaneously, the regular and uniform braiding structure ensures the reinforcing layer has sufficient fiber coverage to guarantee uniform pressure resistance and dimensional stability, while also maintaining appropriate yarn gaps to facilitate the full penetration of hot melt adhesive into the fiber bundles during weaving, improving interlayer bonding strength and significantly enhancing the long-term creep resistance and overall service reliability of the pipe repair hose under high-temperature conditions.

[0037] In Example 7, in step 400, the barrel temperature of the co-extruder forming the outer hot melt adhesive layer is in the range of 180°C-220°C.

[0038] In this embodiment, preferably, the barrel temperature of the co-extruder forming the outer hot melt adhesive layer is in the range of 180℃-220℃.

[0039] In this embodiment, the raw material of the outer hot melt adhesive layer is heated and plasticized in the barrel of the co-extruder that forms the outer hot melt adhesive layer to obtain the raw material of the outer hot melt adhesive layer in a molten state, and then extruded into the second co-extrusion die through the die head.

[0040] The method for preparing the pipe repair hose in this embodiment controls the barrel temperature of the co-extruder to form the outer hot melt adhesive layer, ensuring that the raw material of the outer hot melt adhesive is fully plasticized and melted, resulting in a uniform melt state and moderate fluidity. This temperature range avoids insufficient plasticization or decreased adhesive activity of the outer hot melt adhesive due to excessively low temperatures, while also preventing aging and failure of the hot melt adhesive due to excessively high temperatures. A suitable barrel temperature allows the outer hot melt adhesive to fully contact and wet the surface of the reinforcing fiber layer after entering the second co-extrusion die, while simultaneously achieving a good match with the melt temperature of the outer layer material, resulting in uniform co-extrusion coating and tight interfacial bonding. Stable process temperature parameters yield a uniformly thick and reliably bonded outer hot melt adhesive layer, effectively improving the interlayer peel strength between the outer layer and the reinforcing layer, reducing the risk of outer layer delamination and peeling under long-term operating conditions, and further enhancing the overall structural stability and long-term service reliability of the hose.

[0041] In Example 8, in step 400, the barrel temperature of the co-extruder forming the outer layer is in the range of 180°C-220°C, and the die temperature of the co-extruder forming the outer layer is in the range of 210°C-250°C.

[0042] In this embodiment, preferably, the barrel temperature range of the co-extruder forming the outer layer is 180℃-220℃, and the die temperature range of the co-extruder forming the outer layer is 210℃-250℃.

[0043] In this embodiment, the raw material of the outer layer is heated and plasticized in the barrel of the co-extruder that forms the outer layer to obtain the raw material of the outer layer in a molten state, and then extruded into the second co-extrusion die through the die head.

[0044] The method for manufacturing the pipe repair hose in this embodiment involves a coordinated design of the barrel temperature and die temperature of the co-extruder forming the outer layer. This ensures that the raw material for the outer layer is fully plasticized and melted, resulting in a uniform and stable melt flow. This temperature range avoids incomplete plasticization, uneven material output, or surface defects caused by low temperatures, while also preventing thermal degradation or performance impairment caused by high temperatures. The appropriate temperature parameters match the flowability of the outer layer melt with the outer hot melt adhesive layer melt, ensuring a smooth co-extrusion coating process, tight interfacial bonding, and uniform outer layer wall thickness after molding. This effectively improves the molding quality and overall structural strength of the outer layer, reduces the risk of cracking or breakage during use, and guarantees the long-term stability of the pipe repair hose.

[0045] In Example 9, in step 500, the cooling temperature range of the cooling treatment is 15℃-30℃, and the cooling time ranges from 20s to 120s.

[0046] In this embodiment, preferably, the cooling temperature range is 15℃-30℃, and the cooling time range is 20s-120s.

[0047] The method for manufacturing the pipe repair hose in this embodiment, by controlling the cooling temperature and cooling time, allows the multi-layer composite hose to gradually cool and solidify, enabling rapid shaping of each layer. This parameter range avoids incomplete shaping or dimensional rebound deformation of the pipe repair hose due to excessively high cooling temperature or insufficient cooling time, while also preventing increased internal stress or surface cracking caused by excessively low cooling temperature or rapid cooling. The gentle and controllable low-temperature cooling method ensures that the bonding state of each layer interface is not damaged, guaranteeing the roundness and wall thickness uniformity of the hose, further improving the dimensional accuracy, structural integrity, and appearance quality of the hose.

[0048] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0049] In Example 10, a pipe repair hose is provided, which is prepared using the pipe repair hose preparation method described in any one of Examples 1 to 9, for example... Figure 1Steps 100 to 500 shown are omitted here to avoid repetition.

[0050] In this embodiment, as Figure 2 The diagram shows a cross-sectional view (left) and a longitudinal view (right) of the pipe repair hose. In this diagram, 1 is the outer layer of the pipe repair hose, 2 is the outer hot melt adhesive layer of the pipe repair hose, 3 is the reinforcing layer of the pipe repair hose, 4 is the inner hot melt adhesive layer of the pipe repair hose, and 5 is the inner layer of the pipe repair hose.

[0051] In Example 11, the barrel temperature range of the co-extruder forming the inner layer of the pipe repair hose is 140℃-220℃, the die temperature range is 190℃-230℃, and the melt temperature range is 170℃-210℃. The barrel temperature range of the co-extruder forming the inner hot melt adhesive layer of the pipe repair hose is 180℃-220℃, the die temperature range is 200℃-240℃, and the screw speed is adjusted according to the thickness requirements of the inner hot melt adhesive layer. Sizing is performed using a vacuum sizing chamber with a vacuum level ranging from 0.005MPa to 0.05MPa, a sizing time of 30s, and a sizing temperature of 15℃. Heating is performed using an oven with a temperature of 120℃, a heating time of 10s, and a heating temperature of 80℃. The weaving process is performed using a circular loom with both warp and weft yarns of 44000D. The weft density is 17.5 × 2 threads / 10cm, with a total of 832 warp threads. The weaving structure is a double twill weave, and the weight of the hanging cylinder is 45g-60g. The co-extruder barrel temperature range for forming the outer hot melt adhesive layer of the pipe repair hose is 180℃-220℃, and the screw speed is adjusted according to the required thickness of the outer hot melt adhesive layer. The co-extruder barrel temperature range for forming the outer layer of the pipe repair hose is 180℃-220℃, the die temperature range is 210℃-250℃, and the screw speed is adjusted according to the required extrusion volume of the outer layer of the pipe repair hose. The cooling process involves a cooling temperature of 1℃ and a cooling time of 50s. Using the above process parameters, the pipe repair hose prepared according to the preparation method of the pipe repair hose described in Example 1 can be used for a long time at 70°C, with a burst pressure of 0.7MPa and a peel strength greater than or equal to 120N / 25mm.

[0052] While specific embodiments of the invention have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should also understand that various modifications can be made to the embodiments without departing from the scope and spirit of the invention. The scope of this invention is defined by the appended claims.

Claims

1. A method for preparing a pipe repair hose, characterized in that, The method for preparing the pipe repair hose includes: Step 100: Using two co-extrusion machines, the raw materials for the inner layer and the inner hot melt adhesive layer of the pipe repair hose are simultaneously extruded into the first co-extrusion mold for molding, and then sizing is performed to obtain the inner layer and the inner hot melt adhesive layer of the pipe repair hose. Step 200: Heat the inner hot melt adhesive layer to obtain an inner hot melt adhesive layer in a molten or semi-molten state. Step 300: Weaving is performed on the outer side of the inner hot melt adhesive layer in the molten or semi-molten state to obtain the reinforcing layer of the pipe repair hose; Step 400: Using two co-extrusion machines, the raw materials for the outer hot melt adhesive layer and the outer layer of the pipe repair hose are simultaneously extruded into the second co-extrusion die for molding, and then sizing is performed to obtain the outer hot melt adhesive layer and the outer layer of the pipe repair hose. Step 500: The outer hot melt adhesive layer and the outer layer are wrapped around the outside of the reinforcing layer, and then a cooling treatment is performed to obtain the pipe repair hose.

2. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 100, the barrel temperature of the co-extruder forming the inner layer is in the range of 140℃-220℃, the die temperature of the co-extruder forming the inner layer is in the range of 190℃-230℃, and the melt temperature of the inner layer forming the inner layer is in the range of 170℃-210℃.

3. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 100, the barrel temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 180℃-220℃, the die temperature of the co-extruder forming the inner hot melt adhesive layer is in the range of 200℃-240℃, and the screw speed of the co-extruder forming the inner hot melt adhesive layer is in the range of 10r / min-25r / min.

4. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 100, the sizing process is performed using a vacuum sizing chamber. The vacuum degree of the vacuum sizing chamber is in the range of 0.005 MPa to 0.05 MPa, the sizing time is in the range of 5 s to 30 s, and the sizing temperature is in the range of 15 ℃ to 20 ℃.

5. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 200, the heating treatment is performed using an oven, wherein the oven temperature ranges from 120℃ to 180℃, the heating time ranges from 10s to 30s, and the heating temperature ranges from 80℃ to 120℃.

6. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 300, the weaving process is a weaving operation using a circular loom. The warp and weft yarn specifications of the circular loom are both 44000D, the weft yarn density ranges from 15×2 ends / 10cm to 20×2 ends / 10cm, the total number of warp ends ranges from 700 to 900, and the weaving structure is a twill weave structure.

7. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 400, the barrel temperature of the co-extruder forming the outer hot melt adhesive layer is in the range of 180℃-220℃.

8. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 400, the barrel temperature of the co-extruder forming the outer layer is in the range of 180℃-220℃, and the die temperature of the co-extruder forming the outer layer is in the range of 210℃-250℃.

9. The method for preparing the pipe repair hose according to claim 1, characterized in that, In step 500, the cooling temperature range of the cooling process is 15℃-30℃, and the cooling time ranges from 20s to 120s.

10. A pipe repair hose, characterized in that, It is prepared using the method for preparing a pipe repair hose as described in any one of claims 1-9.

Images