Water delivery channel and method of making same

Abstract

The application discloses a water delivery channel, comprising: a channel main body, the cross section of the channel main body is U-shaped or rectangular, and a flow channel is arranged on the channel main body; and a three-dimensional fiber mesh cloth reinforcing layer, which is inlaid on the channel main body and sequentially comprises a first polyester fiber mesh cloth reinforcing layer, a fiber bundle layer and a second polyester fiber mesh cloth reinforcing layer, wherein the fiber bundles in the fiber bundle layer connect the first polyester fiber mesh cloth reinforcing layer and the second polyester fiber mesh cloth reinforcing layer to form a three-dimensional network structure. The water delivery channel has high strength, good impact resistance and reliable sealing connection.

Description

Technical Field

[0001] This invention belongs to the technical field of agricultural irrigation and water conservancy engineering facilities, and specifically relates to a water conveyance channel and its preparation method. Background Technology

[0002] Irrigation channels are crucial infrastructure in farmland irrigation and drainage projects. While traditional concrete or masonry channels offer high strength, they suffer from drawbacks such as heavy weight, long construction periods, susceptibility to cracking and leakage, and difficult maintenance. In recent years, channels made from polymer materials like PVC have gained increasing popularity, offering advantages such as easy installation and corrosion resistance.

[0003] However, existing PVC irrigation channels are mostly extruded from a single material, resulting in limited structural strength, especially compressive strength and impact resistance. In practical applications, the following technical challenges exist: First, when the channels are buried in fields, they are susceptible to deformation or cracking due to agricultural machinery. Second, in cold northern regions, the stress caused by frost heave in the channel foundation can easily lead to cracking of the channel body. Third, existing PVC channels are mostly simple channel structures with a ring stiffness generally below 8 kN / m², significantly lower than that of concrete channels, making it difficult to meet the engineering requirements of high-fill areas or areas with heavy machinery traffic.

[0004] On the other hand, PVC pipeline water conveyance technology has developed rapidly. For example, PVC-O pipes and fiber-reinforced composite pipes have advantages such as high strength and high toughness. However, the pipeline system is a closed water conveyance system, which is not convenient for open irrigation in the fields. Therefore, how to effectively apply fiber-reinforced technology to open water conveyance channels and adapt it to the special stress conditions of the channels has become a technical problem that urgently needs to be solved in this field.

[0005] Furthermore, the external wall reinforcements of existing PVC channels are mostly simple hollow protrusions, increasing the moment of inertia only through geometric shape, resulting in limited reinforcement. Under high external pressure loads, the reinforcements themselves are prone to local buckling or crushing, failing to effectively transfer the load. Simultaneously, the connection methods of existing PVC channels are mostly simple socket joints, making it difficult to guarantee sealing and unable to withstand axial tensile forces. Therefore, designing a water conveyance channel that combines good structural strength and reliable sealing performance is another technical challenge of this invention. Summary of the Invention

[0006] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a water conveyance channel and its preparation method, which combines high strength, good impact resistance, and reliable sealing connection.

[0007] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A water conveyance channel, comprising: The main body of the channel has a U-shaped or rectangular cross-section and is provided with flow channels. A three-dimensional fiber mesh reinforcement layer is embedded in the channel body. The three-dimensional fiber mesh reinforcement layer includes a first polyester fiber mesh reinforcement layer, a fiber bundle layer and a second polyester fiber mesh reinforcement layer in sequence. The fiber bundles in the fiber bundle layer connect the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer to form a three-dimensional network structure.

[0008] In some embodiments of the present invention, the outer wall of the channel body is provided with a plurality of annular reinforcing ribs spaced along the length direction, and the annular reinforcing ribs are covered with fiber bundles.

[0009] In some embodiments of the present invention, the annular reinforcing rib is a solid structure that protrudes outward and surrounds the circumference of the channel body, and its cross-section is semi-circular, trapezoidal or rectangular.

[0010] In some embodiments of the present invention, the cellulose in the fiber bundle layer and the fiber bundle in the annular reinforcing rib are selected from at least one of glass fiber, carbon fiber, basalt fiber or aramid fiber.

[0011] In some embodiments of the present invention, the interval between two adjacent annular reinforcing ribs along the length direction of the channel body is 150-500mm, the protrusion height of the annular reinforcing rib is 10-30mm, and the width is 15-40mm.

[0012] In some embodiments of the present invention, the ratio of the protrusion height to the width of the annular reinforcing rib is 0.6-0.8:1.

[0013] In some embodiments of the present invention, the linear density of the fiber bundles within the annular reinforcing rib is 600-2400 tex, and the winding density within the annular reinforcing rib is 2-5 turns per centimeter.

[0014] In some embodiments of the present invention, the main body of the channel is made of PVC material.

[0015] In some embodiments of the present invention, the groove edge of the channel body is provided with an outwardly folded connecting flange, and the connecting flange is provided with a connecting hole.

[0016] In some embodiments of the present invention, a plurality of connecting holes are provided at intervals along the length direction on the connecting flange.

[0017] In some embodiments of the present invention, the connecting flange and the channel body are integrally formed, and the thickness of the connecting flange is 1.2-1.5 times the wall thickness of the channel body.

[0018] In some embodiments of the present invention, one end of the channel body is provided with a receiving interface and the other end is provided with a plug interface, wherein the outer diameter of the plug interface is adapted to the inner diameter of the receiving interface to form an overlapping structure.

[0019] In some embodiments of the present invention, the inner wall of the receiving interface is provided with a mounting groove, and a sealing gasket is provided in the mounting groove, the sealing gasket being able to cooperate with the outer wall of the insertion interface to seal.

[0020] In some embodiments of the present invention, when the main body of the channel is spliced, the receiving interface and the insert interface of the adjacent main body of the channel are spliced ​​and installed by locking bolts. The locking bolts pass through the connecting holes on the connecting flanges of the two adjacent sections of the channel body and are locked, so that the sealing gasket in the installation groove is deformed by pressure to achieve sealing.

[0021] A method for preparing a water conveyance channel as described above, characterized by comprising the following steps: S1. Preparation of three-dimensional fiber mesh reinforcement layer: High-strength polyester fibers are woven to form a first polyester fiber mesh reinforcement layer and a second polyester fiber mesh reinforcement layer, and the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer are connected by longitudinally connecting fiber bundles to form a three-dimensional fiber mesh reinforcement layer, wherein the fiber bundles between the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer form a fiber bundle layer. S2. Preheat the mold: Preheat the extrusion mold to 150-180℃; S3. Impregnation and composite: The three-dimensional fiber mesh reinforcement layer obtained in step S1 is introduced into the extrusion die through the guide roller, and the molten PVC matrix material is injected into the die at the same time, so that the PVC matrix material is fully impregnated into the three-dimensional fiber mesh reinforcement layer to form a composite structure preform. S4. Cooling and forming: The impregnated and composite preform is introduced into a vacuum forming mold. Under a vacuum of -0.04MPa to -0.08MPa, the preform is tightly attached to the surface of the U-shaped or rectangular cavity. At the same time, the preform is cooled and formed by circulating water in the forming mold, forming a preliminary preform of the channel body in a thermoplastic state. S5. Rib Forming: When the main body of the channel is still in a thermoplastic state, a ring-shaped rib is formed on its outer wall by vacuum adsorption. During the ring-shaped rib forming process, pre-impregnated fiber bundles are injected simultaneously, so that the fiber bundles are wrapped inside the ring-shaped rib. S6. Flange Forming: On the channel body after the reinforcing ribs are formed, an outwardly folded connecting flange is formed at the edge of the channel opening through a mold pressing process. S7. Post-processing: cooling and shaping, length cutting, inspection and packaging.

[0022] In some embodiments of the present invention, step S5 specifically includes the following steps: S5-1. The channel body blank with a surface temperature of 50-70℃ is pulled to the reinforcing rib forming station, and an annular groove mold cavity is formed on the outer wall of the blank by vacuum adsorption mold, with a vacuum degree of -0.04MPa to -0.08MPa. S5-2. Two streams of material are simultaneously injected into the annular groove mold cavity through a dual-channel metering system. The first stream is molten PVC matrix material with a temperature of 170-190℃ and an injection pressure of 6-10MPa. The second stream is a fiber bundle pre-impregnated with a coupling agent, and the fiber bundle is conveyed at a speed of 0.5-2m / min. S5-3. Under the combined action of vacuum adsorption and melt flow pressure, the fiber bundle automatically spreads out circumferentially in the annular groove and is completely immersed in the PVC matrix material, forming a fiber bundle-PVC composite reinforcement structure. S5-4. Maintain the vacuum adsorption state for 10-30 seconds to allow the reinforcing rib structure to fully solidify.

[0023] In some embodiments of the present invention, in step S6, the flange forming is carried out by heating the channel body after the reinforcing ribs have been formed and cooled, so that the edge of the channel opening reaches a thermoplastic state, and then using a pressing mold to fold the edge of the channel opening outward to form a connecting flange, and simultaneously stamping or subsequent processing on the flange to form a connecting hole.

[0024] In some embodiments of the present invention, in step S1, the three-dimensional fiber mesh reinforcement layer has a plain weave or twill weave structure for its surface and bottom layers, with a unit area mass of 150-350 g / m² and a fiber bundle weaving density of 2-8 bundles per centimeter.

[0025] In some embodiments of the present invention, in step S3, the impregnation and composite pressure is 8-10 MPa, the temperature is 175-185°C, and the introduction speed of the three-dimensional fiber mesh reinforcement layer is 0.3-0.8 m / min.

[0026] In some embodiments of the present invention, in step S4, the cooling and shaping method is multi-stage water cooling, with cooling water temperatures of 60°C, 40°C, and 20°C in sequence, and each stage of cooling time being 1-3 minutes.

[0027] In some embodiments of the present invention, in step S5, the injection of the fiber bundle adopts an intermittent control method, specifically including: setting up a fiber storage device to store continuous fiber bundles from the yarn bobbin during the period when the fiber bundle is stopped from being conveyed; setting up a pinch roller driven by a servo motor to precisely control the start and stop of the fiber bundle and the conveying speed; after the reinforcing rib is formed, the fiber bundle is cut by a cutting mechanism so that the end of the fiber bundle is embedded in the formed reinforcing rib; when the next reinforcing rib position is reached, the pinch roller is restarted to send the fiber bundle into the mold.

[0028] In some embodiments of the present invention, the cutting mechanism is a hot cutter with a temperature controlled at 200-250°C, which simultaneously melts and seals the ends of the fiber bundle during cutting.

[0029] In some embodiments of the present invention, in step S5, during the vacuum adsorption molding process, the wall thickness reduction rate of the initial blank of the channel body in the annular reinforcing rib area is controlled within the range of 10%-18%.

[0030] In some embodiments of the present invention, in step S7, the fixed-length cutting adopts a flying saw cutting method, the saw carriage and the traction speed are synchronously tracked, the U-shaped contour clamping device clamps the channel body before cutting, and the circular saw blade is fed to cut at a speed of 2000-3000 rpm.

[0031] In some embodiments of the present invention, after step S6, a socket forming process is further included, in which a socket and a plug are formed at the end of the cut channel body by a secondary heating forming process. The inner diameter of the socket is larger than the outer diameter of the plug to form an overlapping structure, and a sealing gasket installation groove is formed on the inner wall of the socket for installing the sealing gasket.

[0032] The beneficial effects of this invention are: (1) Significant enhancement effect of three-dimensional network structure: By embedding a three-dimensional fiber mesh reinforcement layer in the main body of the channel, the present invention forms a skeleton structure similar to reinforced concrete. The fiber bundles connect the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer into a whole. When the channel is bent or compressed, the fiber bundles act as shear pins, effectively preventing interlayer peeling. According to the test, the bending strength of the water conveyance channel of the present invention can reach 38.5MPa, which is 124% higher than that of ordinary PVC channels; the impact resistance is improved by more than 85%.

[0033] (2) Synergistic reinforcement by fiber-reinforced ribs: By setting annular ribs with continuous fiber bundles inside, the annular stiffness of the channel is significantly improved. The continuous fiber bundles inside the ribs are distributed along the circumferential direction and directly bear the circumferential tensile stress, resulting in a reinforcement efficiency far higher than that of traditional hollow ribs. Testing shows that the annular stiffness of this invention can reach 12-15 kN / m², meeting the requirements for heavy machinery passage areas in the "Design Code for Irrigation Canals". The local crushing load of the ribs is more than 75% higher than that of ribs without fiber wrapping.

[0034] (3) Reliable connection and sealing: This invention adopts a combined sealing structure of "socket lap joint + flange bolt crimping + sealing gasket". The socket and spigot joint form an lap joint, providing initial positioning and axial constraint; the connecting flange is tightened by locking bolts, providing a reliable mechanical connection; the sealing gasket in the socket joint deforms under the action of flange clamping force, filling the lap gap and achieving a reliable seal. This triple-protection sealing structure solves the industry problem of easy leakage at traditional channel connections. After water pressure test, the joint can withstand an internal water pressure of 0.2MPa without leakage.

[0035] (4) Excellent resistance to freezing and cracking: The introduction of a three-dimensional fiber-reinforced structure significantly improves the low-temperature crack resistance of the channel. After freeze-thaw cycle tests, no cracks were generated on the surface of the channel of the present invention, while microcracks appeared in ordinary PVC channels after 50 cycles.

[0036] (5) The water conveyance channel provided by the present invention can be widely used in the fields of high-standard farmland construction, water-saving irrigation projects, landscaping, municipal drainage, etc. Its preparation method adopts continuous production line operation, with high production efficiency, stable product quality, and wide source of raw materials, and has good industrial production prospects and promotion and application value. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the water conveyance channel according to Embodiment 1 of the present invention; Figure 2 for Figure 1 Enlarged view of section A in the middle; Figure 3 for Figure 1 Enlarged view of section B; Figure 4 This is a top view of the water conveyance channel according to Embodiment 1 of the present invention.

[0038] Figure label: 100. Channel body; 101. Flow channel; 102. Annular reinforcing rib; 103. Connecting flange; 104. Connecting hole; 105. Socket; 106. Insertion; 107. Mounting groove; 108. Sealing gasket; 109. Locking bolt; 110. Continuous glass fiber bundle; 201. Three-dimensional fiber mesh reinforcement layer; 201a. First polyester fiber mesh reinforcement layer; 201b. Fiber bundle layer; 201c. Second polyester fiber mesh reinforcement layer. Detailed Implementation

[0039] The present invention will be further described below with reference to specific embodiments.

[0040] Example 1: A type of water conveyance channel, such as Figure 1 and Figure 2As shown, the irrigation canals and farm canals applicable to high-standard farmland construction projects include a canal body 100 and a three-dimensional fiber mesh reinforcement layer 201. The canal body 100 is made of PVC material and has a U-shaped cross-section. A flow channel 101 is provided on the canal body 100. The canal body 100 has a depth of 300mm, a width of 400mm at the opening, and a wall thickness of 8mm.

[0041] like Figure 2 As shown, the three-dimensional polyester fiber mesh reinforcement layer 201 is embedded in the channel body 100. The three-dimensional polyester fiber mesh reinforcement layer 201 includes a first polyester fiber mesh reinforcement layer 201a, a fiber bundle layer 201b, and a second polyester fiber mesh reinforcement layer 201c. The first polyester fiber mesh reinforcement layer 201a and the second polyester fiber mesh reinforcement layer 201c are both plain-weave polyester fiber mesh fabrics with a unit area mass of 200g / m². The fiber bundles in the fiber bundle layer 201b connect the first polyester fiber mesh reinforcement layer 201a and the second polyester fiber mesh reinforcement layer 201c to form a three-dimensional network structure. The fiber bundles in the fiber bundle layer 201b are evenly distributed at intervals of 5mm along the channel length direction and have a height of 6mm. This structure allows the reinforcement layer to form a three-dimensional skeleton after molding, effectively constraining the deformation of the PVC matrix. The outer wall of the channel body 100 is provided with annular reinforcing ribs 102 at 200mm intervals. The cross-section of the annular reinforcing rib 102 is semi-circular, with a protrusion height of 15mm and a bottom width of 25mm. The height-to-width ratio is 0.6. The annular reinforcing rib 102 is covered with continuous glass fiber bundles 110. The continuous glass fiber bundles 110 are 1200tex E-glass, pretreated with silane coupling agent KH-570 and impregnated with DOP plasticizer. The continuous glass fiber bundles 110 are wound around the annular reinforcing rib 102 in the circumferential direction for about 4 turns, with a winding density of about 3 turns per centimeter.

[0042] like Figure 3 and Figure 4 As shown, the channel body 100 has an outwardly folded connecting flange 103 at the edge of the channel opening. The connecting flange 103 is 50mm wide and 10mm thick, and has connecting holes 104 with a diameter of 12mm spaced 300mm apart, which are used to connect and fix adjacent channel units by locking bolts 109.

[0043] One end of the channel body 100 is provided with a receiving interface 105, and the other end is provided with a plug interface 106. The receiving interface 105 is a flared structure with an inner diameter 10mm larger than the outer diameter of the channel body 100 and a depth of 150mm. The outer diameter of the plug interface 106 is adapted to the inner diameter of the receiving interface 105, and the insertion length is 120mm, forming an overlapping structure. The inner wall of the receiving interface 105 is provided with a 2mm deep installation groove 107 for placing a sealing gasket 108. The sealing gasket 108 is made of rubber. When the channel bodies 100 are spliced, the receiving interfaces 105 and plug interfaces 106 of adjacent channel bodies 100 are spliced ​​and installed by locking bolts 109. The locking bolts 109 pass through the connecting holes 104 on the connecting flanges 103 of the two adjacent channel body sections 100 and are locked, so that the sealing gasket 108 in the installation groove 107 is deformed by pressure to achieve sealing.

[0044] A method for preparing a water conveyance channel as described above includes the following steps: (1) Preparation of three-dimensional fiber mesh reinforcement layer 201: High-strength polyester fiber is selected, and a three-dimensional weaving process is used to prepare a prefabricated first polyester fiber mesh reinforcement layer 201a and a second polyester fiber mesh reinforcement layer 201c. The first polyester fiber mesh reinforcement layer 201a and the second polyester fiber mesh reinforcement layer 201c adopt a plain weave structure with a unit area mass of 200g / m². The first polyester fiber mesh reinforcement layer 201a and the second polyester fiber mesh reinforcement layer 201c are connected by longitudinal connecting fiber bundles. The longitudinal connecting fiber bundles are implanted by rapier weaving with a weaving density of 4 bundles per centimeter to form a three-dimensional fiber mesh reinforcement layer 201. The fiber bundles between the first polyester fiber mesh reinforcement layer 201a and the second polyester fiber mesh reinforcement layer 201c form a fiber bundle layer 201b. (2) Mold preheating: Heat the extrusion mold to 165°C and keep it warm for 30 minutes; (3) Impregnation and composite: The three-dimensional fiber mesh reinforcement layer 201 is introduced into the extrusion die at a uniform speed through the flattening device and guide rollers. The introduction speed is 0.5m / min. At the same time, the PVC compound (100 parts of SG-5 type PVC resin, 3 parts of calcium-zinc composite stabilizer, 2 parts of ACR processing aid, and 10 parts of light calcium carbonate) is plasticized by a twin-screw extruder and injected into the die. The injection pressure is controlled at 8MPa and the melt temperature is 185℃, so that the PVC melt fully impregnates the three-dimensional fiber mesh reinforcement layer 201 to form a bubble-free composite preform. (4) Cooling and shaping: Vacuum Shaping: After the impregnation and lamination of the preform leaves the extrusion die, it immediately enters the vacuum shaping mold. This shaping mold consists of an upper mold and a lower mold, which, when closed, forms a U-shaped conforming cavity that completely fits the outer wall of the channel body 100. The inner wall of the shaping mold is divided into zones according to the geometric characteristics of the U-shaped cross-section: three rows of 1.5mm diameter adsorption holes are set along the length of the channel bottom area, with a longitudinal spacing of 80mm; two rows of adsorption holes are set on each of the two side wall areas, with a longitudinal spacing of 80mm. The vacuum adsorption holes in each area are connected to independent vacuum channels, and the adsorption force can be controlled by adjusting valves. The vacuum system is activated to achieve a vacuum degree of -0.06MPa in the cavity. The preform, which is in a softened state, is tightly adsorbed onto the surface of the U-shaped cavity of the shaping mold under negative pressure, obtaining a precise cross-sectional shape and size. At the same time, 18℃ circulating cooling water is introduced into the shaping mold to pre-cool the preform, so that its surface solidifies to form a skin with a certain shape retention ability. The length of the vacuum shaping section is 6000mm, and the traction speed is matched with the extrusion speed.

[0045] Water cooling: After vacuum shaping, the preform leaves the shaping mold and enters a three-stage water cooling tank for deep cooling. The cooling tank uses contour rollers adapted to the cross-sectional shape of the channel to support the preform and prevent deformation. The temperatures of the three stages of the water tank are 60℃, 40℃, and 20℃ respectively, with a cooling time of 2 minutes for each stage. This multi-stage cooling method with stepped cooling helps to reduce internal stress and prevent warping deformation caused by rapid cooling. Temperature control: After multi-stage water cooling, the surface temperature of the channel body 100 initial billet drops to 55-60℃, and the core layer temperature is about 85℃. At this point, the initial billet has sufficient shape stability, but still retains a certain degree of thermoplasticity, providing conditions for the subsequent vacuum adsorption molding of the annular reinforcing rib 102; (5) Forming of the annular reinforcing rib 102: Process preparation: The channel body 100 blank with a surface temperature of 55-60℃ is pulled to the annular reinforcing rib 102 forming station. This station is equipped with a segmented vacuum adsorption mold. The inner wall of the mold is machined with an annular groove. The shape of the groove is consistent with the cross-sectional shape of the designed annular reinforcing rib 102. Vacuum adsorption and synchronous injection: When the predetermined position on the pre-formed billet of the channel body 100 reaches the center of the mold, the mold closes, forming a closed annular cavity between the outer wall of the pre-formed billet and the inner wall of the mold. The vacuum system is activated to achieve a vacuum of -0.06MPa in the annular cavity, adsorbing the thermoplastic outer wall of the pre-formed billet into the annular groove to form the geometric contour of the annular reinforcing rib 102. Simultaneously with vacuum adsorption, two streams of material are synchronously injected into the annular cavity through a dual-channel precision metering system: the first stream is molten PVC matrix material. The first strand is conveyed through the hot runner 101 system at an injection pressure of 8 MPa and a temperature of 180°C. The second strand is a continuous glass fiber bundle 110 pre-impregnated with silane coupling agent, which is introduced into the annular cavity through the fiber bundle inlet tube at a conveying speed of 1.2 m / min. Under the combined action of vacuum adsorption and melt flow pressure, the continuous fiber bundle automatically spreads circumferentially in the annular cavity and is completely immersed in the injected PVC melt. The vacuum adsorption state is maintained for 20 seconds to fully shape the annular reinforcing rib 102 area. Then the vacuum is released and the mold is opened. Intermittent control of fiber bundles: Throughout the production process, continuous glass fiber bundles are controlled intermittently. The yarn bobbin is continuously unwound, but the fiber bundle is stored during periods of inactivity via a fiber storage device. The pinch rollers are driven by a servo motor, precisely controlling the start and stop of the fiber bundle. After the annular reinforcing rib 102 is formed, a hot cutter cuts the fiber bundle just before the mold entrance, embedding the fiber bundle end within the formed annular reinforcing rib 102. When the next annular reinforcing rib 102 is reached, the pinch rollers restart, feeding the fiber bundle into the mold. This cycle repeats, achieving continuous production. Temperature compensation: If the surface temperature of the billet is lower than 40°C due to the adjustment of the production line speed, the infrared auxiliary heating device will be activated before entering the ring reinforcing rib 102 forming station to heat the surface temperature of the billet to 95-105°C to ensure that the material has good thermoplastic deformation ability. (6) Flange forming: After the annular reinforcing rib 102 is formed and cooled, the channel body 100 enters the flange forming station. The edge of the channel is locally heated to 110° to make it thermoplastic. Then, the pressing mold is used to press from both sides to the middle, and the edge of the channel is folded outward by 90° to form the connecting flange 103. At the same time as the folding and forming, the punching device on the mold simultaneously punches the connecting hole 104 on the flange. After holding the pressure and cooling for 10 seconds, the mold is released and the flange forming is completed. (7) Post-processing: Online cutting: The formed channel body 100 passes through the flying saw cutting machine continuously. When the channel body 100 reaches the set length of 6 meters, the control system issues a command, the saw car accelerates to be synchronized with the traction, the U-shaped conforming clamping device clamps the blank, and the circular saw blade feeds quickly to cut. The whole cutting process takes about 8 seconds, and the cutting length accuracy is ±2mm. Socket forming: The cut channel section enters the socket forming station, where a secondary heating forming process is used to form a socket 105 and a plug 106 at the end. The socket 105 is formed by heating with a flaring mold, increasing the inner diameter by 10mm and the depth by 150mm. At the same time, a sealing gasket 108 and a mounting groove 107 with a depth of 2mm are formed on the inner wall. The plug 106 maintains its original size to ensure an overlapping fit with the socket 105. Inspection and Packaging: After the finished products are inspected for appearance and dimensions, they are automatically stacked or packaged and put into storage. In use, multiple channel bodies 100 are joined together by the socket 105 and the insertion interface 106 to form an overlapping fit. The connecting flange 103 is connected by the locking bolt 109. The sealing gasket 108 in the socket 105 deforms under the pressure of the connecting flange 103, filling the overlapping gap and achieving a reliable seal.

[0046] Example 2: A water conveyance channel differs from Embodiment 1 in that: the main cross-section of the channel is rectangular, suitable for high-flow water conveyance scenarios; the channel depth is 500mm, the channel width is 600mm, and the wall thickness is 10mm; the unit area mass of the first and second polyester fiber mesh reinforcement layers is 300g / m²; the fiber bundles in the fiber bundle layer are evenly distributed at 8mm intervals along the channel length direction, with a height of 9mm; the protrusion height of the reinforcing ribs is 20mm, the width is 30mm, and the height-to-width ratio is 0.67; the annular reinforcing ribs inside the reinforcing ribs are set at 300mm intervals; the continuous fiber bundles are made of carbon fiber with a linear density of 800tex; the flange width is 60mm, the thickness is 12mm, and the connection hole spacing is 250mm; otherwise, it is completely the same as Embodiment 1.

[0047] The method for preparing a water conveyance channel as described above differs from Example 1 in that: in step (3), the introduction speed of the three-dimensional fiber mesh reinforcement layer is controlled to be 0.4 m / min, the injection pressure is 10 MPa, and the melt temperature is 190 °C; in step (5), the vacuum degree is -0.07 MPa, the PVC injection pressure is 10 MPa, the fiber bundle conveying speed is 0.8 m / min, and the vacuum adsorption state is maintained for 25 seconds, and the rest is exactly the same as Example 1.

[0048] Comparative Example 1: A water conveyance channel differs from Example 1 in that the channel body only contains a first polyester fiber mesh reinforcement layer and a second polyester fiber mesh reinforcement layer, and does not contain a fiber bundle layer. Other structures and preparation methods are the same as in Example 1.

[0049] Comparative Example 2: A water conveyance channel differs from Example 1 in that: no fiber bundles are provided inside the annular reinforcing ribs; the other structures and preparation methods are the same as in Example 1.

[0050] Test Example 1: The relevant mechanical properties of the water conveyance channels in the embodiments and comparative examples were tested respectively, and the test results are shown in Table 1.

[0051] Table 1.

[0052] The results show that the water conveyance channel of the present invention has a bending strength of 38.5 MPa or higher, an impact strength of 0℃ that does not crack, a ring stiffness of 13.2 kN / m² or higher, a local crushing load of the reinforcing ribs of 5.6 kN or higher, a Vicat softening temperature of 82℃ or higher, and a linear expansion coefficient of 3.8 × 10⁻⁶. -5 / ℃, no cracks after 100 freeze-thaw cycles, no leakage under 0.2MPa water pressure at the interface, and no interlayer cracking after bending.

[0053] Test Example 2: To verify the feasibility of vacuum shaping of the U-shaped channel, the inventors of this invention conducted specific tests on the vacuum shaping process. Using the same U-shaped cross-section as in Example 1, shaping tests were conducted under different vacuum conditions, and the dimensional deviations of the cross-section after shaping were measured. The results are shown in Table 2 below.

[0054] Table 2.

[0055] The results show that within a vacuum range of -0.04 MPa to -0.08 MPa, the U-shaped channel can achieve good shaping results, with dimensional deviations controlled within ±1 mm. Therefore, the vacuum range of -0.04 MPa to -0.08 MPa selected in this invention is the preferred parameter for vacuum shaping of the U-shaped channel.

[0056] Test Example 3: To verify the deformation control effect of the reinforcing rib forming of the present invention, a comparative experiment was set up: Test group A: In step (5), the initial billet temperature is 55-60℃, the vacuum degree is -0.06MPa, and the holding time is 20 seconds.

[0057] Test group B: In step (5), the initial billet temperature is 80℃, the vacuum degree is -0.06MPa, and the holding time is 10 seconds.

[0058] Experimental group C: In step (5), the initial billet temperature was 55-60℃, the vacuum degree was -0.10MPa, and the holding time was 20 seconds. The results are shown in Table 3 below.

[0059] Table 3.

[0060] Results analysis: Experimental group A showed the best performance in terms of reinforcing rib forming quality and overall performance, indicating that the process parameters of the present invention achieved the best balance between forming capacity and deformation control.

[0061] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A water conveyance channel, characterized in that: include: The main body of the channel has a U-shaped or rectangular cross-section and is provided with flow channels. A three-dimensional fiber mesh reinforcement layer is embedded in the channel body. The three-dimensional fiber mesh reinforcement layer includes a first polyester fiber mesh reinforcement layer, a fiber bundle layer and a second polyester fiber mesh reinforcement layer in sequence. The fiber bundles in the fiber bundle layer connect the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer to form a three-dimensional network structure.

2. A water conveyance channel according to claim 1, characterized in that: The outer wall of the channel body is provided with several annular reinforcing ribs spaced along the length direction, and fiber bundles are wrapped inside the annular reinforcing ribs.

3. A water conveyance channel according to claim 1, characterized in that: The channel body has an outwardly folded connecting flange at the edge of the channel opening, and the connecting flange has a connecting hole.

4. A water conveyance channel according to claim 1, characterized in that: One end of the channel body is provided with a receiving interface and the other end is provided with a plug interface. The outer diameter of the plug interface is adapted to the inner diameter of the receiving interface to form an overlapping structure.

5. A water conveyance channel according to claim 4, characterized in that: The inner wall of the receiving interface is provided with a mounting groove, and a sealing gasket is provided in the mounting groove. The sealing gasket can cooperate with the outer wall of the insertion interface to seal.

6. A method for preparing a water conveyance channel as described in any one of claims 1-5, characterized in that: Includes the following steps: S1. Preparation of three-dimensional fiber mesh reinforcement layer: High-strength polyester fibers are woven to form a first polyester fiber mesh reinforcement layer and a second polyester fiber mesh reinforcement layer, and the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer are connected by longitudinally connecting fiber bundles to form a three-dimensional fiber mesh reinforcement layer, wherein the fiber bundles between the first polyester fiber mesh reinforcement layer and the second polyester fiber mesh reinforcement layer form a fiber bundle layer. S2. Preheat the mold: Preheat the extrusion mold to 150-180℃; S3. Impregnation and composite: The three-dimensional fiber mesh reinforcement layer obtained in step S1 is introduced into the extrusion die through the guide roller, and the molten PVC matrix material is injected into the die at the same time, so that the PVC matrix material is fully impregnated into the three-dimensional fiber mesh reinforcement layer to form a composite structure preform. S4. Cooling and forming: The impregnated and composite preform is introduced into a vacuum forming mold. Under a vacuum of -0.04MPa to -0.08MPa, the preform is tightly attached to the surface of the U-shaped or rectangular cavity. At the same time, the preform is cooled and formed by circulating water in the forming mold, forming a preliminary preform of the channel body in a thermoplastic state. S5. Rib Forming: When the main body of the channel is still in a thermoplastic state, a ring-shaped rib is formed on its outer wall by vacuum adsorption. During the ring-shaped rib forming process, pre-impregnated fiber bundles are injected simultaneously, so that the fiber bundles are wrapped inside the ring-shaped rib. S6. Flange Forming: On the channel body after the reinforcing ribs are formed, an outwardly folded connecting flange is formed at the edge of the channel opening through a mold pressing process. S7. Post-processing: cooling and shaping, length cutting, inspection and packaging.

7. The method for preparing a water conveyance channel according to claim 6, characterized in that: In step S5, the forming of the reinforcing rib specifically includes the following steps: S5-1. The channel body blank with a surface temperature of 50-70℃ is pulled to the reinforcing rib forming station, and an annular groove mold cavity is formed on the outer wall of the blank by vacuum adsorption mold, with a vacuum degree of -0.04MPa to -0.08MPa. S5-2. Two streams of material are simultaneously injected into the annular groove mold cavity through a dual-channel metering system. The first stream is molten PVC matrix material with a temperature of 170-190℃ and an injection pressure of 6-10MPa. The second stream is a fiber bundle pre-impregnated with a coupling agent, and the fiber bundle is conveyed at a speed of 0.5-2m / min. S5-3. Under the combined action of vacuum adsorption and melt flow pressure, the fiber bundle automatically spreads out circumferentially in the annular groove and is completely immersed in the PVC matrix material, forming a fiber bundle-PVC composite reinforcement structure. S5-4. Maintain the vacuum adsorption state for 10-30 seconds to allow the reinforcing rib structure to fully solidify.

8. The method for preparing a water conveyance channel according to claim 6, characterized in that: In step S6, the flange forming is carried out by heating the groove edge to a thermoplastic state on the channel body after the reinforcing ribs have been formed and cooled, and then using a pressing mold to fold the groove edge outward to form a connecting flange, and simultaneously stamping or subsequent processing to form a connecting hole on the flange.

9. A method for preparing a water conveyance channel according to claim 6, characterized in that: In step S3, the impregnation and composite pressure is 8-10 MPa, the temperature is 175-185℃, and the introduction speed of the three-dimensional fiber mesh reinforcement layer is 0.3-0.8 m / min.

10. A method for preparing a water conveyance channel according to claim 6, characterized in that: After step S6, the process also includes a socket forming process, in which a socket and a plug are formed at the end of the cut channel body through a secondary heating forming process. The inner diameter of the socket is larger than the outer diameter of the plug to form an overlapping structure, and a gasket installation groove is formed on the inner wall of the socket for installing the gasket.

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