A processing device and method for a molded thin-wall large-diameter plastic inspection well

Abstract

The application discloses a kind of moulding thin-walled large-diameter plastic inspection well processing device and method, the device includes No. 1 frame, No. 2 frame, No. 3 frame, electric heating device, heat preservation storage mode, storage mode moving cylinder, cylinder moving cylinder, cylinder, concave forming groove, concave forming groove moving cylinder, electric control device I, hydraulic oil supply device, hydraulic oil conveying pipeline and electric control device II.The application is convenient and fast, and the comprehensive cost is low, is not disturbed by injection molding process and hot rolling plastic process, and the inspection well with thin-walled large-diameter, light weight, strong bearing capacity and adaptability is produced by scientific moulding process.

Description

Technical Field

[0001] This invention belongs to the field of plastic inspection well manufacturing technology, specifically relating to a molding device and method for processing thin-walled large-diameter plastic inspection wells. Background Technology

[0002] Inspection wells, commonly known as "manholes," are auxiliary structures installed at the junctions, bends, changes in pipe diameter or slope, drop structures, or at regular intervals along straight pipelines to facilitate periodic inspection and unblocking of the pipes. Plastic inspection wells offer advantages such as good sealing performance, corrosion resistance, aging resistance, easy installation, convenient construction, and simple maintenance.

[0003] Currently, large plastic inspection wells are generally produced using injection molding, hot extrusion and cold pressing, and rotational molding methods. Injection molding involves using a large plastic injection molding machine and injection molds. Electrical and hydraulic control devices control the front and rear mold plates of the clamping mechanism, and plastic is injected into the mold through the screw of the injection molding machine. High pressure is applied to fill the mold cavity with plastic. The molten plastic cools and solidifies within the mold before demolding. However, this molding method has high temperature requirements for the plastic. On the one hand, the selection of plastic materials is limited; the shrinkage rate and density of plastic cooling in a molten state are difficult to guarantee, especially for thin-walled, large-diameter plastic inspection wells, where the quality and specifications cannot meet the requirements. On the other hand, injection molding uses complex production equipment and numerous molds, which are expensive, requiring high investment costs and production inventory, hindering its widespread adoption in China. Hot extrusion and cold pressing involves heating the plastic to a molten state, applying pressure, and molding through the interaction of a concave and convex mold. This method also requires high temperatures for the plastic. In the production of thin-walled, large-diameter plastic inspection wells, the plastic exhibits significant shrinkage, which is detrimental to molding. Furthermore, the molten plastic tends to stick to the inner wall of the concave mold, leading to demolding difficulties and increasing the labor intensity for workers. Rotational molding: Compared to injection molding, rotational molding equipment and molds are relatively inexpensive, making it suitable for processing large plastic parts. However, the design of rotational molding molds needs to fully consider the flow characteristics of the molten plastic. It is difficult to control the density, rigidity, thickness, and wall thickness uniformity of the produced thin-walled, large-diameter plastic inspection well structure. The molded plastic inspection wells suffer from defects in shrinkage and density parameters. Moreover, it has low production efficiency and high labor intensity, making it unsuitable for mass production of large plastic inspection wells. Due to the high cost, low quality, and long production time of thin-walled, large-diameter plastic inspection wells, most domestic sewage pipe networks still use brick or reinforced concrete inspection wells. However, brick and reinforced concrete inspection wells themselves have unsatisfactory anti-leakage effects. Furthermore, due to the rapid development of chemical building materials such as plastics, domestic sewage pipe networks use a large number of plastic pipes. The different materials of brick, reinforced concrete, and plastic pipes make it impossible to solve leakage problems when connecting them, which is detrimental to environmental protection.

[0004] The published patent, "A Modular Injection Molding Device for Large-Scale Combined Plastic Inspection Well Chambers," publication number CN107139383A, describes a molding method where molten plastic flows through an injection runner gate to a group injection molding device. Inside the device, the plastic cools and solidifies to form a large plastic inspection well chamber. However, this method does not involve mold pressure extension processes. Furthermore, this method requires high plastic temperatures; the molten plastic has high fluidity, but poor shrinkage and density, which is unfavorable for the production of thin-walled, large-diameter plastic inspection wells. On the other hand, the cooling and solidification processes of the molten plastic are time-consuming, resulting in low production efficiency.

[0005] The published patent, "Method for Hot Extrusion and Cold Press Molding of Plastic Inspection Wells," publication number CN1986201, describes a molding method where molten plastic at 180-240℃ is extruded into a molding die. The die is then moved laterally to its mating point with a punch, which is pressed into the die. Pressure is applied, and the mold is cooled to form the plastic inspection well or component. However, the high melt index of the plastic and the excessively high temperature result in greater fluidity, making it difficult to guarantee the quality of process parameters during molding. This makes it unsuitable for producing thin-walled, large-diameter plastic inspection wells due to the inability to ensure the required wall thickness, density, and shrinkage rate. Furthermore, at 180-240℃, the plastic tends to stick to the inner wall of the mold, making demolding difficult and increasing the workload for workers.

[0006] The published patent, "A Method for Hot Extrusion and Cold Pressing of Plastic Inspection Wells," publication number CN102514200A, describes a molding method where molten plastic at 110-300℃ is quantitatively extruded into a mold, where it cools and solidifies within the mold cavity. After demolding, the workpiece is assembled into the desired inspection well. This method does not address large, thin-walled plastic inspection well specifications; comparisons can only be made based on the process flow. Similar to the method described above, molten plastic exhibits high fluidity, which is unfavorable for producing thin-walled, large-diameter plastic inspection wells. Furthermore, it tends to adhere to the mold's inner wall during molding, resulting in honeycomb-like holes on the surface of the demolded plastic inspection well, leading to low quality. It also requires a high amount of mold release agent, which is environmentally unfriendly. Summary of the Invention

[0007] The purpose of this invention is to overcome the aforementioned problems in existing methods for producing large plastic inspection wells. It is applicable to plastics with low melt index and specific functional modifications, and provides a molding apparatus and method for processing thin-walled, large-diameter plastic inspection wells. This invention features a simple process, a simple structure for manufacturing thin-walled, large-diameter plastic inspection wells, low energy consumption during production, which helps save resources, high production efficiency, safe manufacturing process, and ensures the quality of the molded plastic inspection wells or their components.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a molding thin-walled large-diameter plastic inspection well processing device, comprising a first frame, a second frame, a third frame, an electric heating device, a heat-insulating storage mold, a storage mold moving cylinder, a roller moving cylinder, a roller, a concave forming groove, a concave forming groove moving cylinder, an electrical control device I, a hydraulic oil supply device, a hydraulic oil conveying pipeline, and an electrical control device II;

[0009] The No. 1 and No. 2 frames are spaced apart. The electric heating device is located on the No. 1 frame and has a material feeding port. The heat-insulating storage mold is located between the No. 1 and No. 2 frames via the No. 3 frame. The cylinder of the storage mold moving cylinder is bolted to the heat-insulating storage mold. The No. 3 frame supports both the heat-insulating storage mold and the storage mold moving cylinder. The heat-insulating storage mold is connected to the discharge end of the electric heating device.

[0010] The concave forming groove is located directly below the heat-insulating storage mold. There is a concave forming groove moving cylinder on each side of it, and the piston rods of the two concave forming groove moving cylinders are connected to the concave forming groove. A limiting rail for guiding the concave forming groove is also provided between the two concave forming groove moving cylinders. The roller moving cylinder is set on the second frame, and the piston rod of the roller moving cylinder is connected to the roller located directly below it.

[0011] Electrical control device I is located near the concave forming groove moving cylinder and is electrically connected to the two concave forming groove moving cylinders; electrical control device II is located near the roller moving cylinder and is electrically connected to the roller moving cylinder.

[0012] The hydraulic oil supply device is connected to the material storage mold moving cylinder, the roller moving cylinder, and the concave forming groove moving cylinder through hydraulic oil delivery pipelines.

[0013] Preferably, the insulated storage mold consists of an outer vacuum layer and a heat-insulating coating disposed within the vacuum layer.

[0014] This invention provides a processing method for the above-mentioned molding thin-walled large-diameter plastic inspection well processing device, the steps of which are as follows:

[0015] Step 1: Plastic is put into the material feeding port and heated to a softening temperature of 67℃-130℃ by an electric heating device. After the plastic reaches the softening temperature, it is sent to the heat preservation storage mold. The temperature of the heat preservation storage mold is controlled at 67℃-130℃.

[0016] Step 2: Start the material storage mold moving cylinder to transport the plastic weighing 20Kg-300Kg in the heat preservation material storage mold to the concave forming groove. The concave forming groove moving cylinder will then move the concave forming groove to the position of the roller.

[0017] Step 3: The roller moving cylinder works, inserting the roller from top to bottom into the concave forming groove. The roller rotates around the inner wall of the concave forming groove under a pressure of 1000KN-40000KN. The outer surface of the roller is squeezed against the inner wall of the concave forming groove, and the plastic is extruded and formed at a softening temperature of 67℃-130℃ to form a plastic inspection well component.

[0018] Step 4: After the roller moving cylinder completes its work, it retracts the roller upwards; the plastic inspection well in the concave forming groove is cooled for 3-20 minutes, and then demolded after cooling.

[0019] The beneficial effects of this invention are:

[0020] 1. This invention is not affected by injection molding or hot rotation molding processes. Through a scientific compression molding process, it produces inspection wells with thin walls, large diameters, light weight, strong load-bearing capacity, and high adaptability. This invention is convenient and quick to construct, and has a low overall cost.

[0021] 2. This invention uses a molding process, which can achieve high output and high efficiency in the production of plastic inspection wells by appropriately adjusting the process parameters of the roller;

[0022] 3. This invention has a low temperature range for plastics, using only the softening temperature of the plastic, thus avoiding high resource consumption. At the same time, the fluidity of the plastic can be controlled within a suitable range, ensuring good density and large shrinkage of the molded thin-walled large-diameter plastic inspection wells. The demolding process is easy, reducing the labor intensity of workers.

[0023] 4. This invention can extend raw materials with a smaller cross-sectional thickness by adjusting the shape and size of the roller, thereby achieving efficient utilization of materials and obtaining thin-walled, large-diameter plastic inspection well components, thus reducing factory costs.

[0024] 5. Through the control and adjustment of the rollers, the plastic undergoes changes such as extrusion, stretching and smoothing, which can significantly improve the surface smoothness and density of plastic inspection well parts. This allows the plastic inspection well parts to obtain highly consistent size and shape accuracy through molding, reducing the need for subsequent processing.

[0025] 6. This invention abandons the traditional method of applying temperatures above 230°C to melt plastics, and instead uses a softening temperature range of 67°C to 130°C. Plastic particles soften within this range, which saves resources, reduces the risk, and accelerates the production speed of thin-walled, large-diameter plastic inspection wells.

[0026] 7. This invention improves production efficiency and processing range, reduces investment in production equipment, lowers product manufacturing and inventory costs, enhances flexibility and applicability in engineering construction, shortens construction cycles, and reduces engineering construction costs, thus having broad application prospects. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the device of the present invention;

[0028] Figure 2 A schematic diagram of an insulated storage mold;

[0029] Figure 3 This is a diagram showing the relationship between the concave forming groove and the moving cylinder of the concave forming groove. Detailed Implementation

[0030] Embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be construed as limiting the scope of the invention. Where specific techniques, connections, or conditions are not specified in the embodiments, they are performed in accordance with the techniques, connections, or conditions described in the literature in the art or according to product instructions. Materials, instruments, or equipment used, unless otherwise specified, are all conventional products that can be purchased.

[0031] The structure of the present invention will now be described with reference to the accompanying drawings.

[0032] like Figure 1-3 As shown, the present invention provides a molding device for processing thin-walled large-diameter plastic inspection wells, including a first frame 1, a second frame 2, a third frame 15, an electric heating device 3, an insulated storage mold 4, a storage mold moving cylinder 5, a roller moving cylinder 6, a roller 7, a concave forming groove 8, a concave forming groove moving cylinder 9, an electrical control device I10, a hydraulic oil supply device 11, a hydraulic oil conveying pipeline 12, and an electrical control device II13;

[0033] Frame 1 and Frame 2 are spaced apart. Electric heating device 3 is installed on Frame 1 and has a material feeding port 14. Insulated storage mold 4 is installed between Frame 1 and Frame 2 via Frame 3 15. Storage mold moving cylinder 5 is bolted to the insulated storage mold 4. Frame 3 15 supports both the insulated storage mold 4 and the storage mold moving cylinder 5. The insulated storage mold 4 is connected to the discharge end of the electric heating device 3.

[0034] The concave forming groove 8 is located directly below the heat-insulating storage mold 4. There is a concave forming groove moving cylinder 9 on each side of it, and the piston rods of the two concave forming groove moving cylinders 9 are connected to the concave forming groove 8. A limiting rail 16 for guiding the concave forming groove 8 is also provided between the two concave forming groove moving cylinders 9. The roller moving cylinder 6 is set on the second frame 2, and the piston rod of the roller moving cylinder 6 is connected to the roller 7 located directly below it.

[0035] The electrical control device I10 is located near the concave forming groove moving cylinder 9, and the electrical control device I10 is electrically connected to the two concave forming groove moving cylinders 9; the electrical control device II13 is located near the roller moving cylinder 6, and the electrical control device II13 is electrically connected to the roller moving cylinder 6.

[0036] The hydraulic oil supply device 11 is connected to the storage mold moving cylinder 5, the roller moving cylinder 6 and the concave forming groove moving cylinder 9 respectively through the hydraulic oil delivery pipe 12.

[0037] Specifically, the heat-insulating storage mold 4 consists of an outer vacuum layer 41 and a heat-insulating coating 42 located inside the vacuum layer 41, with the material 43 stored inside the heat-insulating coating 42; the heat-insulating storage mold 4 is bolted to the No. 3 frame 15.

[0038] The present invention also provides a processing method for the above-mentioned molding thin-walled large-diameter plastic inspection well processing device, the steps of which are as follows:

[0039] Step 1: Plastic is put into the material feeding port 14 and heated to a softening temperature of 67℃-130℃ by the electric heating device 3. After the plastic reaches the softening temperature, it is sent to the heat preservation storage mold 4. The temperature of the heat preservation storage mold 4 is controlled at 67℃-130℃.

[0040] Step 2: Start the storage mold moving cylinder 5 to transport the plastic weighing 20Kg-300Kg in the heat-insulating storage mold 4 to the concave forming groove 8. The concave forming groove moving cylinder 9 will then move the concave forming groove to the position of the roller 7.

[0041] Step 3: The roller moving cylinder 6 works to insert the roller 7 into the concave forming groove 8 from top to bottom. The roller 7 rotates around the inner wall of the concave forming groove 8 under a pressure of 1000KN-40000KN. The outer surface of the roller 7 is squeezed against the inner wall of the concave forming groove 8, and the plastic is squeezed and formed at a softening temperature of 67℃-130℃ to form a plastic inspection well component.

[0042] Step 4: After the roller moving cylinder 6 completes its work, it retracts the roller 7 upwards; the plastic inspection well in the concave forming groove 8 is cooled for 3-20 minutes, and demolding is completed after cooling. The hydraulic oil for the storage mold moving cylinder 5, the roller moving cylinder 6, and the concave forming groove moving cylinder 9 is supplied by the hydraulic oil supply device 11 through the hydraulic oil delivery pipeline 12. The roller moving cylinder 6 and the concave forming groove moving cylinder 9 are servo controlled by the electrical control device I13 and the electrical control device I10, respectively. After demolding, the concave forming groove 8 is transported to the starting position by the concave forming groove moving cylinder 9, waiting for the next work process. Example 1

[0043] The processing method for plastic inspection well components includes the following steps:

[0044] Step 1: Plastic is fed into the material inlet and heated to a softening temperature of 120°C by an electric heating device.

[0045] Step 2: After the plastic reaches a softening temperature of 120℃, it is sent to the heat-insulating storage mold 4, where the temperature is controlled at 130℃.

[0046] Step 3: Start the moving cylinder of the storage mold to transport the 200Kg plastic in the heat-insulating storage mold 4 to the concave forming groove 8.

[0047] Step 4: The concave forming groove moving cylinder 9 moves the concave forming groove to the position of the roller 7.

[0048] Step 5: The roller moving cylinder 6 operates, inserting the roller 7 from top to bottom into the concave forming groove 8. The roller rotates around the inner wall of the concave forming groove 8 under a pressure of 20000KN. The outer surface of the roller 7 is squeezed against the inner wall of the concave forming groove 8, and the plastic is extruded and molded at a softening temperature of 120℃ to form a plastic inspection well component.

[0049] Step 6: After the roller moving cylinder 6 completes its work, it retracts the roller 7 upwards. The plastic inspection well in the concave forming groove 8 is cooled for 10 minutes, and then demolded after cooling is complete. Example 2

[0050] The processing method for plastic inspection well components includes the following steps:

[0051] Step 1: Plastic is fed into the material inlet and heated to a softening temperature of 130°C by an electric heating device.

[0052] Step 2: After the plastic reaches a softening temperature of 130℃, it is sent to the heat-insulating storage mold 4, where the temperature is controlled at 130℃.

[0053] Step 3: Start the moving cylinder of the storage mold to transport the 300Kg plastic in the heat-insulating storage mold 4 to the concave forming groove 8.

[0054] Step 4: The concave forming groove moving cylinder 9 moves the concave forming groove to the position of the roller 7.

[0055] Step 5: The roller moving cylinder 6 operates, inserting the roller 7 from top to bottom into the concave forming groove 8. The roller rotates around the inner wall of the concave forming groove 8 under a pressure of 40000KN. The outer surface of the roller 7 is squeezed against the inner wall of the concave forming groove 8, and the plastic is extruded and molded at a softening temperature of 130℃ to form a plastic inspection well component.

[0056] Step 6: After the roller moving cylinder 6 completes its work, it retracts the roller 7 upwards. The plastic inspection well in the concave forming groove 8 is cooled for 20 minutes, and then demolded after cooling is complete.

[0057] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A processing method for a molding device for thin-walled, large-diameter plastic inspection wells, characterized in that, The device includes a first frame (1), a second frame (2), a third frame (15), an electric heating device (3), a heat-insulating storage mold (4), a storage mold moving cylinder (5), a roller moving cylinder (6), a roller (7), a concave forming groove (8), a concave forming groove moving cylinder (9), an electrical control device I (10), a hydraulic oil supply device (11), a hydraulic oil conveying pipeline (12), and an electrical control device II (13); wherein, The No. 1 frame (1) and the No. 2 frame (2) are set apart. The electric heating device (3) is set on the No. 1 frame (1). The electric heating device (3) is provided with a material feeding port (14). The heat-insulating storage mold (4) is set between the No. 1 frame (11) and the No. 2 frame (2) through the No. 3 frame (15). The cylinder of the storage mold moving cylinder (5) is bolted to the heat-insulating storage mold (4). The No. 3 frame (15) supports both the heat-insulating storage mold (4) and the storage mold moving cylinder (5). The heat-insulating storage mold (4) is connected to the discharge end of the electric heating device (3). The concave forming groove (8) is located directly below the heat-insulating storage mold (4), and there is a concave forming groove moving cylinder (9) on each side of it. The piston rods of the two concave forming groove moving cylinders (9) are connected to the concave forming groove (8). A limiting rail (16) for guiding the concave forming groove (8) is also provided between the two concave forming groove moving cylinders (9). The roller moving cylinder (6) is set on the second frame (2), and the piston rod of the roller moving cylinder (6) is connected to the roller (7) located directly below it. Electrical control device I (10) is located near the concave forming groove moving cylinder (9), and electrical control device I (10) is electrically connected to the two concave forming groove moving cylinders (9); electrical control device II (13) is located near the roller moving cylinder (6), and electrical control device II (13) is electrically connected to the roller moving cylinder (6). The hydraulic oil supply device (11) is connected to the material storage mold moving cylinder (5), the roller moving cylinder (6) and the concave forming groove moving cylinder (9) respectively through the hydraulic oil conveying pipe (12); The processing method of the device is as follows: Step 1: Plastic is put into the material feeding port (14) and heated to a softening temperature of 67℃-130℃ by the electric heating device (3). After the plastic reaches the softening temperature, it is sent to the heat preservation storage mold (4). The temperature of the heat preservation storage mold (4) is controlled at 67℃-130℃. Step 2: Start the storage mold moving cylinder (5) to transport the plastic with a mass of 20Kg-300Kg in the heat-insulating storage mold (4) to the concave forming groove (8), and the concave forming groove moving cylinder (9) moves the concave forming groove to the position of the roller (7); Step 3: The roller moving cylinder (6) works to insert the roller (7) from top to bottom into the concave forming groove (8). The roller (7) rotates around the inner wall of the concave forming groove (8) under a pressure of 1000KN-40000KN. The outer surface of the roller (7) is squeezed against the inner wall of the concave forming groove (8). The plastic is squeezed and formed at a softening temperature of 67℃-130℃ to form a plastic inspection well component. Step 4: After the roller moving cylinder (6) finishes its work, it will retract the roller (7) upwards; the plastic inspection well in the concave forming groove (8) will be cooled for 3-20 minutes, and demolded after cooling.

2. The processing method of the molding thin-walled large-diameter plastic inspection well processing device according to claim 1, characterized in that, The heat-insulating storage mold (4) consists of an outer vacuum layer (41) and a heat-insulating coating (42) located inside the vacuum layer (41).

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