A forming mechanism of a composite pipe production equipment

Abstract

This invention provides a forming mechanism for composite pipe production equipment, belonging to the field of composite pipe technology. It solves the problem in existing technologies where the reinforcing fibers are damaged during composite pipe production, thus affecting product quality. The forming mechanism of this composite pipe production equipment includes an outer pipe, a forming mold, and a water storage tank. The outer mold has an inlet port and an outlet port. One end of the outer pipe extends into the outer mold from the inlet port. An annular cavity is formed between the outer peripheral wall of the outer pipe and the inner peripheral wall of the outer mold, directly opposite the forming cavity. The water storage tank has a front port and a rear port arranged opposite each other, with the front port directly opposite the outlet port of the outer mold. A flexible, annular front support ring is fixedly installed at the front port. The inner hole of the front support ring is opposite to the front port of the water storage tank, and the diameter of the inner hole is smaller than the diameter of the front port. This invention enables composite pipes with uniform wall thickness and high straightness, resulting in higher quality.

Description

Technical Field

[0001] This invention belongs to the field of composite pipe technology and relates to a forming mechanism for composite pipe production equipment. Background Technology

[0002] With the continuous expansion and construction of cities, as well as the ongoing extraction of oil and natural gas, the demand for transportation pipelines is increasing. Traditional steel pipelines, with their poor corrosion resistance and difficulty in handling, can no longer meet current needs. Fiber-reinforced composite pipes, due to their low density, high strength, and excellent mechanical properties, such as good processing performance, excellent chemical stability, and heat resistance, are widely used.

[0003] Existing fiber-reinforced composite pipes typically consist of three layers from the inside out: an inner layer, a reinforcing layer, and an outer layer. In terms of manufacturing principles, the pipe blank is first extruded using an extruder, and then the reinforcing fibers are wound onto the surface of the pipe blank using a winding machine and bonded together with an adhesive to form a fiber-reinforced composite pipe.

[0004] In addition, there are some new methods and equipment for manufacturing composite tubes. For example, a composite tube production equipment disclosed in patent literature (application number: 202111507938.9) includes a forming mold, a support base, an outer tube, and a winding machine that can wrap reinforcing fibers onto the outer peripheral wall of the outer tube. A forming cavity is formed between the outer mold sleeve and the core mold of the forming mold. One end of the outer tube extends into the outer mold sleeve. An annular cavity is formed between the outer peripheral wall of the outer tube and the inner peripheral wall of the outer mold sleeve, which is directly opposite to the forming cavity. The support base is equipped with rollers located on the lower side of the outer tube. The rollers can provide rolling support for the reinforcing fibers on the outer peripheral wall of the outer tube. The support base is also equipped with an adjustment structure that can adjust the height and position of the rollers. This equipment, by setting up rollers, relies on the rollers to provide rolling support for the reinforcing fibers on the outer peripheral wall of the outer tube, so that the outer tube can be supported during the production process. Although this device can ensure that the outer tube and the outer mold sleeve always have a high degree of concentricity during the manufacturing process, the reinforcing fibers on the lower side of the outer tube will be squeezed by the rollers when supported by the rollers. The contact area between the rollers and the reinforcing fibers is small and the local pressure is large, which can cause damage or wear to the reinforcing fibers, thus affecting the quality of the product. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a forming mechanism for composite pipe production equipment. The technical problem solved by this invention is: how to improve the quality of composite pipes.

[0006] The objective of this invention can be achieved through the following technical solution: A forming mechanism for a composite pipe production equipment includes an outer pipe, a forming mold having an outer mold sleeve and a forming cavity, the outer mold sleeve having an inlet port and an outlet port, one end of the outer pipe extending into the outer mold sleeve from the inlet port, and an annular cavity formed between the outer peripheral wall of the outer pipe and the inner peripheral wall of the outer mold sleeve, which is directly opposite to the forming cavity. The forming mechanism further includes a water storage tank, which has a front port and a rear port arranged opposite to each other, and the front port is directly opposite the outlet port of the outer mold sleeve. A flexible, annular front support ring is fixedly provided at the front port, the inner hole of the front support ring being opposite to the front port of the water storage tank and the diameter of the inner hole being smaller than the diameter of the front port.

[0007] During the production process, the winding machine wraps the reinforcing fiber onto the outer circumferential wall of the outer tube. At this time, since one end of the outer tube extends into the outer mold sleeve, and the outer circumferential wall of the outer tube and the inner circumferential wall of the outer mold sleeve form an annular cavity that is directly opposite the forming cavity, the reinforcing fiber layer on the outer circumferential wall of the outer tube can pass through the forming cavity and combine with the molten material entering the forming cavity to form a fiber-reinforced composite tube. The tube is then pulled out from the discharge port of the outer mold sleeve, enters the water storage tank through the front port, and then extends out from the rear port of the water storage tank. Finally, the composite tube is shaped and cooled by a vacuum sizing box.

[0008] In this production equipment, because the outer wall of the outer tube needs to be covered with reinforcing fibers that move relative to it, the support frame of the outer tube can only support the part of the outer tube that does not need to be covered with reinforcing fibers, resulting in the end of the outer tube extending into the outer mold sleeve being suspended in the air. In this molding mechanism, by setting up a water storage tank and installing a front support ring on the water storage tank, the composite tube can pass through the inner hole of the front support ring. The front support ring serves two purposes: firstly, it acts as a seal; secondly, because the inner diameter of the front support ring is smaller than the diameter of the front end of the water storage tank, there is a floating gap between the outer wall of the composite tube and the front end of the water storage tank. Therefore, the buoyancy generated by the water in the water storage tank can support the composite tube. With the auxiliary support of the front support ring, it can effectively prevent the composite tube from sagging and bending, and also prevent the concentricity between the outer mold sleeve and the outer tube from decreasing due to the sagging of the composite tube. This ensures that the composite tube has uniform wall thickness and high straightness, resulting in a high-quality composite tube.

[0009] In the forming mechanism of the aforementioned composite pipe production equipment, a water inlet pipe is provided at the bottom of the water storage tank near the front port. The bottom of the water storage tank has a guide cavity with an upper opening located inside the tank. The water inlet pipe is vertically arranged, with its upper end extending into the bottom of the guide cavity. When water enters through the inlet pipe, the guide cavity guides the water flow into the water storage tank, causing the water flow to concentrate and flow upward, forming a water jet that supports the composite pipe, thereby increasing the buoyancy of the composite pipe. Furthermore, the water inlet pipe is located near the front port of the water storage tank, and the composite pipe at this position is in a flexible hose shape due to insufficient cooling. At this time, the upward water jet can effectively support the composite pipe at this position, ensuring high straightness and good quality of the composite pipe.

[0010] In the forming mechanism of the aforementioned composite pipe production equipment, the water storage tank has a front end plate and a rear end plate arranged opposite to each other. The front port of the water storage tank is opened on the front end plate and the rear port is opened on the rear end plate. A baffle plate 1 is provided on the inner wall of the bottom of the water storage tank, which is parallel to the front end plate. Baffle plate 2 is connected to the two vertical sides of the baffle plate 1, and the end of the baffle plate 2 away from the baffle plate 1 is connected to the inner wall of the front end plate. The baffle plate 1, baffle plate 2 and the front end plate together form the aforementioned flow guiding cavity. By setting baffle plate 1 and baffle plate 2 in the water storage tank to form the flow guiding cavity, it is not only simple to manufacture and low in cost, but also the flow guiding cavity formed can have a large depth, thereby effectively forming a water jet that supports the composite pipe upward and improving the buoyancy of the composite pipe.

[0011] In the forming mechanism of the aforementioned composite pipe production equipment, the front port of the water storage tank is circular, and the diameter of the front port is larger than the diameter of the discharge port of the outer mold sleeve. The circular front port is easier to manufacture, and the larger diameter of the front port compared to the discharge port of the outer mold sleeve ensures a sufficient floating gap between the outer circumferential wall of the composite pipe and the front port of the water storage tank, guaranteeing that the buoyancy generated by the water in the tank provides good support for the composite pipe.

[0012] In the forming mechanism of the aforementioned composite pipe production equipment, a water outlet is provided on the rear end plate, and the height of the water outlet is higher than that of the rear end. The water outlet being higher than the rear end allows the water in the storage tank to completely submerge the composite pipe, thereby subjecting the composite pipe to a greater buoyancy.

[0013] In the forming mechanism of the composite pipe production equipment described above, the front end plate is provided with two front support rings. The two front support rings are respectively attached to the inner and outer side walls of the front end plate. One of the front support rings has a pressure ring on its side facing away from the front end plate. The pressure ring is provided with a bolt. The bolt passes through the pressure ring, the front support ring on the outer side wall of the front end plate, the front end plate, and the front support ring (6) on the inner side wall of the front end plate in sequence and is screwed with a nut. Since the front support ring has the dual function of sealing and supporting the composite pipe, the provision of two front support rings here can increase the sealing effect and the support effect on the composite pipe, making it difficult for water in the water tank to flow out from the front port of the water tank. At the same time, the two front support rings and the buoyancy of the water work together to support the composite pipe, greatly improving the support effect on the composite pipe, preventing the composite pipe from sagging and bending, and making the produced composite pipe have high quality. Installing the two front support rings by the pressure ring and the bolt is not only convenient to manufacture, but also improves the stability of the front support ring installation.

[0014] In the forming mechanism of the aforementioned composite pipe production equipment, a rear support ring is provided on the outer wall of the rear end plate. A pressure ring is provided on the side of the rear support ring facing away from the rear end plate. A bolt is provided on the pressure ring, and the bolt passes sequentially through the pressure ring, the rear support ring, and the rear end plate, and is screwed with a nut. The rear support ring serves two purposes: sealing and auxiliary support for the composite pipe. Installing the rear support ring using the pressure ring and bolts not only facilitates manufacturing but also improves the stability of the rear support ring installation.

[0015] In the forming mechanism of the aforementioned composite pipe production equipment, both the front and rear support rings are made of silicone material, and their inner diameters are equal and they are concentrically arranged. The silicone material used for the front and rear support rings offers advantages such as water resistance, resistance to aging, and durability.

[0016] In the forming mechanism of the aforementioned composite pipe production equipment, this forming mechanism also includes a vacuum sizing box. The water storage tank is located between the forming mold and the vacuum sizing box, and the rear port of the water storage tank is directly opposite the pipe inlet of the vacuum sizing box. The composite pipe is cured and cooled in the vacuum sizing box, resulting in good cooling effect, thus making the outer diameter of the composite pipe uniform and less prone to deformation.

[0017] Compared with existing technologies, the forming mechanism of this composite pipe production equipment has the following advantages:

[0018] 1. The production principle of this invention is completely different from that of existing equipment. This invention does not first extrude the tube blank through an extruder and then wind the reinforcing fiber onto the surface of the tube blank through a winding machine. Instead, it forms the molten material and continuous reinforcing fiber into a composite tube in one step in the forming mold. In this way, the molten material can be compatible and penetrate with the reinforcing fiber in the forming mold, so the bonding effect is better and the strength is higher. It does not have the problem of weak interlayer bonding that causes the pipe strength to weaken, which exists in composite tubes produced by existing equipment.

[0019] 2. This invention incorporates a water storage tank in the molding die and vacuum sizing box. The water storage tank provides cooling to the composite pipe, increasing the cooling time and thus improving the cooling effect. Furthermore, the buoyancy of the water in the tank supports the composite pipe, preventing it from sagging or bending. This also prevents sagging from reducing the concentricity between the outer mold sleeve and the outer pipe, ensuring uniform wall thickness and high straightness, resulting in high-quality composite pipes. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention.

[0021] Figure 2 This is a partial sectional view of the forming mechanism.

[0022] Figure 3 This is a cross-sectional view of the molding die.

[0023] Figure 4 This is a top view of the water storage tank.

[0024] Figure 5 yes Figure 4 Sectional view of AA.

[0025] Figure 6 yes Figure 4 A cross-sectional view of BB.

[0026] In the diagram, 1. Outer tube; 2. Molding mold; 21. Outer mold sleeve; 211. Feed port; 212. Discharge port; 22. Molding cavity; 23. Core mold; 3. Support frame; 4. Annular cavity; 5. Water storage tank; 51. Front end plate; 511. Front port; 52. Rear end plate; 521. Rear port; 522. Water outlet; 53. Water inlet pipe; 54. Guide cavity; 55. Baffle one; 56. Baffle two; 6. Front support ring; 7. Pressure ring one; 8. Bolt one; 9. Rear support ring; 10. Bolt two; 11. Nut one; 12. Nut two; 13. Vacuum sizing box; 131. Pipe inlet; 14. Winding machine; 15. Extruder; 16. Composite pipe; 17. Pressure ring two. Detailed Implementation

[0027] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0028] like Figure 1 As shown, the forming mechanism of the composite pipe production equipment includes an extruder 15, a support frame 3, a winding machine 14, a forming mold 2, a water storage tank 5, a vacuum sizing box 13, and a traction machine arranged in a straight line. The traction machine is not shown in the figure. The function of the traction machine is to continuously pull the formed composite pipe 16 forward.

[0029] Combination Figure 1 , Figure 2 and Figure 3 As shown, this molding mechanism also includes an outer tube 1, and a molding die 2 including an outer mold sleeve 21 and a core mold 23 disposed within the outer mold sleeve 21. A molding cavity 22 is formed between the core mold 23 and the outer mold sleeve 21. The outer mold sleeve 21 has an inlet port 211 and an outlet port 212. One end of the outer tube 1 extends into the outer mold sleeve 21 from the inlet port 211. An annular cavity 4 is formed between the outer peripheral wall of the outer tube 1 and the inner peripheral wall of the outer mold sleeve 21, which is directly opposite to the molding cavity 22. The other end of the outer tube 1 is fixed to a support frame 3, which provides support for the outer tube 1. Figure 4 and Figure 5 As shown, the water storage tank 5 has a front port 511 and a rear port 521 arranged opposite to each other. The front port 511 is directly opposite the discharge port 212 of the outer mold sleeve 21. The front port 511 of the water storage tank 5 is circular, and the diameter of the front port 511 is larger than the diameter of the discharge port 212 of the outer mold sleeve 21. The rear port 521 of the water storage tank 5 is directly opposite the pipe inlet 131 of the vacuum sizing box 13. A ring-shaped and flexible front support ring 6 is fixedly provided at the front port 511. The inner hole of the front support ring 6 is opposite to the front port 511 of the water storage tank 5, and the diameter of the inner hole is smaller than the diameter of the front port 511. During the production process, the winding machine 14 wraps the reinforcing fiber onto the outer peripheral wall of the outer tube 1. Since one end of the outer tube 1 extends into the outer mold sleeve 21, and an annular cavity 4 is formed between the outer peripheral wall of the outer tube 1 and the inner peripheral wall of the outer mold sleeve 21, directly opposite the forming cavity 22, the reinforcing fiber layer on the outer peripheral wall of the outer tube 1 can pass through the forming cavity 22 and combine with the molten material entering the forming cavity 22, forming a fiber-reinforced composite tube 16. This tube is then pulled out from the outlet port 212 of the outer mold sleeve 21, enters the water storage tank 5 through the front port 511, and extends from the rear port 521 of the water storage tank 5. Finally, the composite tube 16 is shaped and cooled by the vacuum sizing box 13. Typically, a tube cutting machine is also installed to cut the composite tube 16 from the traction machine to the required length.

[0030] Furthermore, such as Figure 4 , Figure 5 and Figure 6As shown, the water storage tank 5 has a front end plate 51 and a rear end plate 52 arranged opposite to each other. The front port 511 of the water storage tank 5 is opened on the front end plate 51, and the rear port 521 is opened on the rear end plate 52. A water inlet pipe 53 is provided at the bottom of the water storage tank 5 near the front port 511. The bottom of the water storage tank 5 has a guide cavity 54 with an open top. The water inlet pipe 53 is arranged vertically and its upper end extends into the bottom of the guide cavity 54. A water outlet 522 is provided on the rear end plate 52, and the height of the water outlet 522 is higher than that of the rear port 521. Specifically, a baffle 55 is provided on the inner wall of the bottom of the water storage tank 5, which is parallel to the front end plate 51. A baffle 56 is connected to the two vertical sides of the baffle 55. The end of the baffle 56 away from the baffle 55 is connected to the inner wall of the front end plate 51. The baffle 55, the baffle 56 and the front end plate 51 enclose the aforementioned guide cavity 54. When water enters the inlet pipe 53, the guide cavity 54 guides the water flow into the water storage tank 5, causing the water flow to concentrate and flow upward to form a water jet that supports the composite pipe 16 upward, thereby increasing the buoyancy of the composite pipe 16.

[0031] like Figure 5 and Figure 6 As shown, the front plate 51 is provided with two front support rings 6 as described above. The two front support rings 6 are respectively attached to the inner and outer side walls of the front plate 51. One of the front support rings 6 has a pressure ring 7 on its side facing away from the front plate 51. The pressure ring 7 has a bolt 8. The bolt 8 passes through the pressure ring 7, the front support ring 6 on the outer side wall of the front plate 51, the front plate 51, and the front support ring 6 on the inner side wall of the front plate 51 in sequence, and is screwed with a nut 11. The outer side wall of the rear plate 52 is provided with a rear support ring 9. The rear support ring 9 has a pressure ring 17 on its side facing away from the rear plate 52. The pressure ring 17 has a bolt 10. The bolt 10 passes through the pressure ring 17, the rear support ring 9, and the rear plate 52 in sequence, and is screwed with a nut 12. Both the front support rings 6 and the rear support ring 9 are made of silicone material. The inner diameters of the front support rings 6 and the rear support ring 9 are equal and they are concentrically arranged.

[0032] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0033] Although this article frequently uses terms such as 1. outer tube; 2. molding die; 21. outer mold sleeve; 211. feed port; 212. discharge port; 22. molding cavity; 23. core mold; 3. support frame; 4. annular cavity; 5. water storage tank; 51. front end plate; 511. front port; 52. rear end plate; 521. rear port; 522. water outlet; 53. water inlet pipe; 54. guide cavity; 55. baffle one; 56. baffle two; 6. front support ring; 7. pressure ring one; 8. bolt one; 9. rear support ring; 10. bolt two; 11. nut one; 12. nut two; 13. vacuum sizing box; 131. pipe inlet; 14. winding machine; 15. extruder; 16. composite pipe; 17. pressure ring two, the possibility of using other terms cannot be excluded. The use of these terms is merely for the convenience of describing and explaining the nature of the invention; interpreting them as any additional limitation would be contrary to the spirit of the invention.

Claims

1. A forming mechanism for a composite pipe production equipment, comprising an outer pipe (1), a forming mold (2) having an outer mold sleeve (21) and a forming cavity (22), wherein the outer mold sleeve (21) has an inlet port (211) and an outlet port (212), one end of the outer pipe (1) extends into the outer mold sleeve (21) from the inlet port (211), and an annular cavity (4) is formed between the outer peripheral wall of the outer pipe (1) and the inner peripheral wall of the outer mold sleeve (21) and is directly opposite to the forming cavity (22), characterized in that, The molding mechanism also includes a water tank (5), which has a front port (511) and a rear port (521) arranged opposite to each other. The front port (511) is directly opposite to the discharge port (212) of the outer mold sleeve (21). A ring-shaped and flexible front support ring (6) is fixedly provided at the front port (511). The inner hole of the front support ring (6) is opposite to the front port (511) of the water tank (5) and the diameter of the inner hole is smaller than the diameter of the front port (511). A water inlet pipe (53) is provided at the bottom of the water tank (5) near the front port (511). The bottom of the water tank (5) has a guide cavity (54) with an upper opening located inside the water tank (5). The water inlet pipe (53) is arranged vertically and its upper end extends into the bottom of the guide cavity (54).

2. The forming mechanism of the composite pipe production equipment according to claim 1, characterized in that, The water storage tank (5) has a front end plate (51) and a rear end plate (52) arranged opposite to each other. The front port (511) of the water storage tank (5) is opened on the front end plate (51) and the rear port (521) is opened on the rear end plate (52). The inner wall of the bottom of the water storage tank (5) is provided with a baffle plate (55) arranged parallel to the front end plate (51). The two vertical sides of the baffle plate (55) are respectively connected to the baffle plate (56). The end of the baffle plate (56) away from the baffle plate (55) is connected to the inner wall of the front end plate (51). The baffle plate (55), the baffle plate (56) and the front end plate (51) enclose and form the above-mentioned flow guiding cavity (54).

3. The forming mechanism of the composite pipe production equipment according to claim 1 or 2, characterized in that, The front port (511) of the water storage tank (5) is circular, and the diameter of the front port (511) is larger than the diameter of the discharge port (212) of the outer mold sleeve (21).

4. The forming mechanism of the composite pipe production equipment according to claim 2, characterized in that, The rear end plate (52) is provided with a water outlet (522), and the height of the water outlet (522) is higher than that of the rear port (521).

5. The forming mechanism of the composite pipe production equipment according to claim 2, characterized in that, The front plate (51) is provided with two front support rings (6) as described above. The two front support rings (6) are respectively attached to the inner side wall and the outer side wall of the front plate (51). One of the front support rings (6) has a pressure ring (7) on the side facing away from the front plate (51). The pressure ring (7) is provided with a bolt (8). The bolt (8) passes through the pressure ring (7), the front support ring (6) on the outer side wall of the front plate (51), the front plate (51), and the front support ring (6) on the inner side wall of the front plate (51) in sequence and is screwed with a nut (11).

6. The forming mechanism of the composite pipe production equipment according to claim 2, characterized in that, A rear support ring (9) is provided on the outer side wall of the rear end plate (52). A pressure ring (17) is provided on the side of the rear support ring (9) facing away from the rear end plate (52). A bolt (10) is provided on the pressure ring (17). The bolt (10) passes through the pressure ring (17), the rear support ring (9) and the rear end plate (52) in sequence and is screwed with a nut (12).

7. The forming mechanism of the composite pipe production equipment according to claim 6, characterized in that, Both the front support ring (6) and the rear support ring (9) are made of silicone material, and the inner diameters of the front support ring (6) and the rear support ring (9) are equal and concentrically arranged.

8. The forming mechanism of the composite pipe production equipment according to claim 1 or 2, characterized in that, The forming mechanism also includes a vacuum sizing box (13), and the water storage box (5) is located between the forming mold (2) and the vacuum sizing box (13). The rear port (521) of the water storage box (5) is directly opposite the pipe inlet (131) of the vacuum sizing box (13).

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