Large-diameter straight pipe pressure-balanced expansion joint with external pressure bellows balance of peripheral equipment

Abstract

A large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance for peripherals is provided with a working bellows. At both sides of the working bellows, one end pipe is respectively connected. Along the circumferential direction on the outer sides of the two end pipes, multiple groups of tie rod assemblies and multiple groups of external bellows balance assemblies for peripherals are arranged. Multiple groups of external bellows balance assemblies for peripherals are evenly distributed in the circumferential direction of each end pipe. The external bellows balance assembly for peripherals consists of a guide plate, an end ring, an external pressure balance body, and a pressure connection pipe. The guide plate and the end ring are sleeved on the end pipe on the same side. Both ends of the external pressure balance body are respectively fixedly connected with the guide plate and the end pipe. The external pressure balance body is provided with an external balance cavity surrounded by an external bellows and a connecting piece. The outer side of the external bellows is located in the external balance cavity. The external balance cavity is communicated with the end pipe on the same side through a pressure connection pipe. Multiple groups of tie rod assemblies are evenly distributed in the circumferential direction of each end pipe. The present invention can greatly reduce the supervision and manufacturing difficulty of the expansion joint and reduce the product cost at the same time.

Description

Technical Field

[0001] The invention belongs to the field of pipeline flexible compensation, and specifically relates to a large-diameter straight pipe pressure balance expansion joint using an external pressure bellows for balance. Background Art

[0002] The straight pipe pressure balance expansion joint can be used to compensate for the axial displacement of the pipeline. Structural components are used to restrain the pipeline blind flange force, and no blind flange force is output to the pipe orifice and the support. The overall structure is as Figure 1 shown. The straight pipe pressure balance expansion joint applied to conventional pipelines (with a diameter less than 4 meters) usually consists of two groups of working bellows, one group of balance bellows and other force-bearing structural components. The diameter of the balance bellows is 1.414 times that of the working bellows. Multiple groups of tie rods are used to transmit the balance force. One end of each tie rod is connected to the end pipe assembly respectively, and the other end is connected to the intermediate pipe assembly.

[0003] For the compensation application of expansion joints with larger pipe diameters, there are difficulties in the design and manufacture of straight pipe pressure balance expansion joints. On the one hand, the huge pipeline blind flange force poses a challenge to the design of structural components. On the other hand, the required diameter of the balance bellows will further increase, greatly increasing its manufacturing difficulty. For example, when the pipeline pressure is 0.2 MPa, for a pipeline with a nominal diameter of 13 meters, the diameter of the balance bellows will reach 18.4 meters, and the blind flange force will reach 5315T. Summary of the Invention

[0004] To solve the above technical problems, the invention provides a large-diameter straight pipe pressure balance expansion joint using an external pressure bellows for balance, which can greatly reduce the supervision and manufacturing difficulty of the expansion joint and at the same time reduce the product cost.

[0005] To achieve the above technical purpose, the technical solution adopted is: a large-diameter straight pipe pressure balance expansion joint using an external pressure bellows for balance, which is provided with working bellows. On both sides of the working bellows, an end pipe is respectively connected. On the outer sides of the two end pipes, multiple groups of tie rod assemblies and multiple groups of external bellows balance assemblies are arranged circumferentially;

[0006] On each end pipe, multiple groups of external bellows balance assemblies are evenly distributed circumferentially. The external bellows balance assembly consists of a guide plate, an end ring, an external pressure balance body and a pressure connection pipe. The guide plate and the end ring are sleeved on the end pipe on the same side. There is a sliding gap between the guide plate and the end pipe. The end ring is fixedly connected to the end pipe. Both ends of the external pressure balance body are fixedly connected to the guide plate and the end pipe respectively. The external pressure balance body includes an external bellows located outside the end pipe. The external pressure balance body is provided with an external balance cavity surrounded by the external bellows and connecting pieces. The outside of the external bellows is located in the external balance cavity. The external balance cavity is communicated with the end pipe on the same side through a pressure connection pipe.

[0007] A plurality of sets of tie rod assemblies are evenly distributed circumferentially around each end pipe. One end of the tie rod assembly is fixedly connected to the guide plate on one side end pipe, and the other end of the tie rod assembly is fixedly connected to the end ring on the other side end pipe.

[0008] The external pressure balance body consists of a force transmission cylinder, a connecting plate, an external corrugated pipe, a fixing plate and an outer cylinder. One end of the force transmission cylinder arranged axially consistent with the expansion joint is connected to the guide plate. The other end of the force transmission cylinder is connected to the connecting plate. The connecting plate is connected to the fixing plate through the external corrugated pipe sleeved outside the force transmission cylinder. The fixing plate is sleeved outside the force transmission cylinder and there is a sliding gap between the fixing plate and the force transmission cylinder. The outer edge of the fixing plate is connected to one end of the outer cylinder sleeved outside the external corrugated pipe. The other end of the outer cylinder is connected to the end ring. The end ring, the outer cylinder, the fixing plate, the external corrugated pipe and the connecting plate enclose an external balance cavity, and this external balance cavity is connected to the end pipe on the same side through a pressure communication pipe.

[0009] A plurality of sets of external corrugated pipe balance assemblies are symmetrically arranged on both sides of the working corrugated pipe.

[0010] The tie rod assemblies are arranged on both sides of each set of external corrugated pipe balance assemblies.

[0011] An optimized balance body is arranged in the middle of the external pressure balance body. The optimized balance body consists of an optimized balance cavity surrounded by an optimized corrugated pipe and a connecting piece. The outside of the optimized corrugated pipe is located in the optimized balance cavity, and this optimized balance cavity is connected to the external balance cavity.

[0012] The tie rod assembly passes through the axis of the optimized balance cavity. One side of the tie rod assembly is connected to the guide plate on the side where the optimized balance cavity is located, and the other end passes through the end ring on the corresponding side and is connected to the end ring on the other side.

[0013] The multiple sets of tie rod assemblies evenly distributed circumferentially around the expansion joint are arranged staggeredly. The beneficial effects of the present invention are as follows: In this invention, multiple sets of small-diameter corrugated pipes are arranged on both sides of the working corrugated pipe of the pipeline, aiming to replace larger-sized balance corrugated pipes in the pipeline. Symmetrical arrangement on both sides can obtain a larger external corrugated pipe balance area, so it can be applied to large-diameter pipeline systems. Since only one set of working corrugated pipe needs to be arranged in the pipeline, the production quantity of large-diameter corrugated pipes is reduced, thus greatly reducing the manufacturing difficulty, production cycle and cost of the product, improving the construction processability. At the same time, the use of multiple sets of external small-diameter balance structures facilitates the maintenance and replacement of each unit in the later stage, and overall improves the reliability of the product.

[0014] An optimized balance body is additionally arranged in the middle of the external pressure balance body, and the displacement of the optimized corrugated pipe is arranged inside the external pressure balance body, which can overall reduce the axial length dimension of the expansion joint and further improve the reliability. Description of the Drawings

[0015] Figure 1 It is the structure and balance force principle diagram of a conventional pipeline straight pipe pressure balance type expansion joint;

[0016] Figure 2 Structural schematic diagram of Embodiment 1 of the present invention;

[0017] Figure 3 Force principle diagram of the present invention;

[0018] Figure 4 Side view schematic diagram of the present invention;

[0019] Figure 5 Three-dimensional schematic diagram of the present invention;

[0020] Figure 6 Structural schematic diagram of Embodiment 2 of the present invention;

[0021] Figure 7 is Figure 6 side view schematic diagram of;

[0022] In the figure: 1. First guide plate, 2. First tie rod assembly, 3. First end ring, 4. Working bellows, 5. Second tie rod assembly, 6. Flow guide cylinder, 7. Second end ring, 8. Connecting plate, 9. Outer cylinder, 10. Outer peripheral bellows cylinder section, 11. Outer peripheral bellows, 12. Force transmission cylinder, 13. Fixed plate, 14. Second guide plate, 15. Tie rod nut, 16. Pressure connection pipe, 17. Outer peripheral balance cavity, 18. Tie rod assembly, 19. Outer peripheral bellows balance assembly, 20. Optimized balance body, 21. Optimized balance cavity, 22. Optimized bellows, 23. First end pipe assembly, 24. Second end pipe assembly. Specific embodiments

[0023] A large-diameter straight pipe pressure balance type expansion joint with outer peripheral external pressure bellows balance is adopted. It is provided with a working bellows, and one end pipe is connected to each side of the working bellows. A plurality of groups of tie rod assemblies and a plurality of groups of outer peripheral bellows balance assemblies are arranged circumferentially on the outer sides of the two end pipes. A plurality of groups of outer peripheral bellows balance assemblies are evenly distributed circumferentially on each end pipe. The outer peripheral bellows balance assembly is composed of a guide plate, an end ring, an external pressure balance body and a pressure connection pipe. The guide plate and the end ring are sleeved on the end pipe on the same side. A sliding gap is provided between the guide plate and the end pipe. The end ring is fixedly connected to the end pipe. The two ends of the external pressure balance body are respectively fixedly connected to the guide plate and the end pipe. The external pressure balance body includes an outer peripheral bellows located outside the end pipe. The external pressure balance body is provided with an outer balance cavity surrounded by the outer peripheral bellows and its connecting parts. The outer side of the outer peripheral bellows is located in the outer balance cavity. The outer balance cavity is communicated with the end pipe on the same side through a pressure connection pipe. The outer peripheral bellows is subjected to the external pressure brought by the medium in the end pipe. A plurality of groups of tie rod assemblies are evenly distributed circumferentially on each end pipe. One end of the tie rod assembly is fixedly connected to the guide plate on one side of the end pipe, and the other end of the tie rod assembly is fixedly connected to the end ring on the other side of the end pipe.

[0024] The external pressure balance body is composed of a force transmission cylinder, a connecting plate, an external bellows, a fixing plate and an outer cylinder. One end of the force transmission cylinder arranged axially consistent with the expansion joint is connected to the guide plate. The other end of the force transmission cylinder is connected to the connecting plate. The connecting plate is connected to the fixing plate through the external bellows sleeved outside the force transmission cylinder. The fixing plate is sleeved outside the force transmission cylinder and there is a sliding gap between the fixing plate and the force transmission cylinder. The outer edge of the fixing plate is connected to one end of the outer cylinder sleeved outside the external bellows. The other end of the outer cylinder is connected to the end ring. The end ring, the outer cylinder, the fixing plate, the external bellows and the connecting plate enclose an external balance cavity, and this external balance cavity is connected to the end pipe on the same side through a pressure connection pipe.

[0025] As Figure 5 shown, multiple groups of external bellows balance components 19 are symmetrically arranged on both sides of the working bellows 4. In this way, a larger external bellows balance area can often be obtained, so it can be popularized and applied to ultra-large diameter pipeline systems in engineering.

[0026] The tie rod assembly 18 is arranged on both sides of each group of external bellows balance components 19, and the ends of the tie rod assembly 18 are fixed by tie rod nuts or welding.

[0027] As Figure 4 、 Figure 5 shown, multiple groups of tie rod assemblies 18 evenly distributed along the circumferential direction of the expansion joint are staggeredly arranged. This arrangement is more reasonable and effective. Taking one external bellows balance component 19 as an example, the tie rod assembly on the left side is located above, and the tie rod assembly on the right side is located below. For the external bellows balance component 19 on the other end pipe corresponding to this external bellows balance component 19, the left tie rod assembly is located below, and the right tie rod assembly is located above. In this way, left-right staggering and front-back staggering are achieved.

[0028] As Figure 6 shown, to further reasonably utilize the space inside the external pressure balance body, an optimized balance body can be provided in the middle of the external pressure balance body. The optimized balance body is an optimized balance cavity surrounded by an optimized bellows and connectors. The outside of the optimized bellows is located inside the optimized balance cavity, and the outside of the optimized bellows is under pressure. This optimized balance cavity is connected to the external balance cavity.

[0029] As Figure 7 shown, after adding the optimized balance body, the optimal setting form of the tie rod bellows is that the tie rod assembly passes through the axis of the optimized balance cavity. One side of the tie rod assembly is connected to the guide plate on the side where the optimized balance cavity is located, and the other end passes through the end ring on the corresponding side and is connected to the end ring on the other side. The external bellows balance components on the two end pipes are staggeredly arranged to realize the connection of the tie rod assemblies and prevent the tie rod assemblies on both sides from interfering with each other.

[0030] The effective area of the working bellows 4 is 2 N times that of the effective area of a single external bellows, Nis the number of groups of circumferentially distributed external corrugated pipes on one side. The number of external corrugated pipe assemblies arranged on both sides may not be equal, but the effective area of the working corrugated pipe is equal to the total area of the external corrugated pipes.

[0031] There are significant differences from the structure of the conventional straight pipe pressure balance type expansion joint. The overall structure is shown in Figure 2 . The core invention point is to replace the balance wave by evenly distributing multiple groups of small-diameter corrugated pipes along the circumference of the end pipe and arranging them on both sides of the working corrugated pipe 4. The balance area of the external corrugated pipes can be doubled as a whole. The pressure connection pipe 16 is used to introduce the medium in the pipeline into each external balance cavity, and the pressure of the external corrugated pipes is the same as the pressure in the pipeline. One end of the tie rod assembly 2 is connected to the end ring 2, and the other end is connected to the guide plate 1. There is a tie rod hole on the end ring 2. One end of the tie rod assembly 5 is connected to the end ring 1, and the other end is connected to the guide plate 2 14. There is a tie rod hole on the end ring 1. The tie rod assemblies are arranged on both sides of each group of external balance structures. Considering the Figure 4 、 Figure 5 of the whole product, the tie rod assembly 2 and the tie rod assembly 5 are arranged alternately. For details, see Figure 4 . The overall structure has only one group of working corrugated pipes 4. Multiple groups of circumferentially distributed external corrugated pipes act as the balance wave. The effective area of the working corrugated pipe 4 is 2 N times that of a single external corrugated pipe. N is the number of groups of circumferentially distributed external corrugated pipes on one side. The overall structure only needs to set one group of working corrugated pipes 4, which reduces the usage amount of corrugated pipe materials and the product cost. At the same time, using multiple groups of small-diameter corrugated pipes instead of larger-diameter balance corrugated pipes can greatly reduce the manufacturing difficulty of the product in the application of large-diameter and even super-large-diameter pipelines. In addition, the designed structure of this invention product also has the characteristics of small required installation length and small overall stiffness of the expansion joint.

[0032] The structural balance principle diagram is shown in Figure 3 . The balance condition is N×(F1 + F2) = F, where F is the blind plate force at one end of the pipeline, F1 and F2 are the corresponding balance forces of a single group of balance structures on both sides of the working corrugated pipe 4, and the total number of balance structures along the circumference is 2 N .

[0033] Embodiment 1

[0034] A large-diameter straight pipe pressure balance type expansion joint using external external pressure corrugated pipes for balance is provided with a working corrugated pipe 4. One end pipe is connected to both sides of the working corrugated pipe 4, and multiple groups of tie rod assemblies 18 and multiple groups of external corrugated pipe balance assemblies are arranged circumferentially on the outside of the two end pipes. The diameter of the working corrugated pipe 4 located in the center is much lower than the diameter of the original balance wave, and the overall outer diameter of the circumferentially arranged multiple groups of external corrugated pipe balance assemblies 19 is also lower than the diameter of the original balance corrugated pipe.

[0035] A plurality of groups of peripheral bellows balancing components 19 are evenly distributed in the circumferential direction of each end pipe. The peripheral bellows balancing components 19 are composed of a guide plate, an end ring, a force transmission cylinder 12, a connecting plate 8, a peripheral bellows 11, a fixing plate 13, an outer cylinder 9 and a pressure connection pipe 16. The guide plate and the end ring are sleeved on the end pipe on the same side. The two are arranged parallel to each other and are perpendicular to the axial direction of the expansion joint. There is a sliding gap between the guide plate and the end pipe. The end ring is fixedly connected to the end pipe to form an end pipe assembly. One end of the force transmission cylinder 12 arranged axially consistent with the expansion joint is connected to the guide plate. The other end of the force transmission cylinder 12 is connected to the connecting plate 8. The connecting plate 8 is connected to the fixing plate 13 through the peripheral bellows sleeved on the outside of the force transmission cylinder 12. The fixing plate 13 is sleeved on the outside of the force transmission cylinder 12 and there is a sliding gap between the fixing plate 13 and the force transmission cylinder 12. The outer edge of the fixing plate 13 is connected to one end of the outer cylinder 9 sleeved on the outside of the peripheral bellows. The other end of the outer cylinder 9 is connected to the second end ring 7. The second end ring 7, the outer cylinder 9, the fixing plate 13, the peripheral bellows and the connecting plate 8 enclose a peripheral balance cavity. The peripheral balance cavity is communicated with the end pipe on the same side through the pressure connection pipe 16. A plurality of groups of tie rod components 18 are evenly distributed in the circumferential direction of each end pipe. One end of the tie rod component 18 is fixedly connected to the guide plate on the end pipe on one side of the working bellows. The other end of the tie rod component 18 is fixedly connected to the first end ring 3 on the end pipe on the other side of the working bellows.

[0036] Embodiment 2

[0037] As Figure 6 、 Figure 7 shown, in order to reduce the force arm of the end pipe assembly (the distance from the tie rod hole to the pipeline), thereby reducing the bending stress and deformation deflection of the root weld of the end pipe assembly and optimizing its stress state, a tie rod bellows is arranged inside the peripheral bellows, which plays the role of medium sealing and tie rod isolation. The axes of the peripheral bellows, the tie rod bellows and the tie rod are coaxial. In this way, the bending force arm of the tie rod force on the end pipe assembly can be reduced as a whole, its stress state and structural deformation can be optimized, and the material consumption can be reduced. The peripheral balance mechanisms on both sides of the working bellows are arranged with tie rods staggered from each other. The tie rod bellows is displaced in the inner cavity of the peripheral bellows. As a whole, the axial length dimension of the expansion joint can be reduced.

[0038] On the basis of Embodiment 1, an optimized balance body is added. The tie rod component passes through the center of the force transmission cylinder, that is, coincides with the axis of the whole external pressure balance body. The optimized balance body is composed of an optimized bellows 22 sleeved on the tie rod component and an end pipe assembly. One end of the optimized bellows 22 is connected to the connecting plate through the first end pipe assembly 23 sleeved on its own outside. The other end of the optimized bellows 22 is connected to the connecting plate or the end ring through the second end pipe assembly 24. The first end pipe assembly, the second end pipe assembly, the optimized bellows and the connecting plate enclose an optimized balance cavity. An opening is made on the connecting plate to communicate the optimized balance cavity and the peripheral balance cavity to realize the optimization of the stress state.

Claims

1. A large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance of peripherals is provided with a working bellows. One end pipe is connected to each side of the working bellows. A plurality of sets of tie rod assemblies and a plurality of sets of external bellows balance assemblies of peripherals are arranged circumferentially on the outer sides of the two end pipes. It is characterized in that: A plurality of sets of external bellows balance assemblies of peripherals are evenly distributed circumferentially on each end pipe. The external bellows balance assembly of peripherals consists of a guide plate, an end ring, an external pressure balance body and a pressure connection pipe. The guide plate and the end ring are sleeved on the end pipe on the same side. A sliding gap is provided between the guide plate and the end pipe. The end ring is fixedly connected to the end pipe. Both ends of the external pressure balance body are fixedly connected to the guide plate and the end pipe respectively. The external pressure balance body includes an external bellows located outside the end pipe. The external pressure balance body is composed of a force transmission cylinder, a connecting plate, an external bellows, a fixing plate and an outer cylinder. One end of the force transmission cylinder arranged in the same direction as the axis of the expansion joint is connected to the guide plate. The other end of the force transmission cylinder is connected to the connecting plate. The connecting plate is connected to the fixing plate through the external bellows sleeved on the outside of the force transmission cylinder. The fixing plate is sleeved on the outside of the force transmission cylinder and there is a sliding gap between the fixing plate and the force transmission cylinder. The outer edge of the fixing plate is connected to one end of the outer cylinder sleeved on the outside of the external bellows. The other end of the outer cylinder is connected to the end ring. The end ring, the outer cylinder, the fixing plate, the external bellows and the connecting plate enclose an external balance cavity. This external balance cavity is communicated with the end pipe on the same side through a pressure connection pipe; An optimized balance body is arranged in the middle of the external pressure balance body. The optimized balance body consists of an optimized balance cavity surrounded by an optimized bellows and a connecting piece. The outside of the optimized bellows is located in the optimized balance cavity. This optimized balance cavity is communicated with the external balance cavity; A plurality of sets of tie rod assemblies are evenly distributed circumferentially on each end pipe. One end of the tie rod assembly is fixedly connected to the guide plate on one side end pipe, and the other end of the tie rod assembly is fixedly connected to the end ring on the other side end pipe.

2. The large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance of peripherals according to claim 1, It is characterized in that: A plurality of sets of external bellows balance assemblies of peripherals are symmetrically arranged on both sides of the working bellows.

3. The large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance of peripherals according to claim 1, It is characterized in that: The tie rod assemblies are arranged on both sides of each set of external bellows balance assemblies of peripherals.

4. The large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance of peripherals according to claim 1, It is characterized in that: The tie rod assembly passes through the axis of the optimized balance cavity. One side of the tie rod assembly is connected to the guide plate on the side where the optimized balance cavity is located, and the other end passes through the end ring on the side where it is located and is connected to the end ring on the other side.

5. The large-diameter straight pipe pressure balance type expansion joint with external pressure bellows balance of peripherals according to claim 3 or 4, It is characterized in that: The plurality of sets of tie rod assemblies evenly distributed along the circumference of the expansion joint are arranged staggeredly.

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