A compound tie rod straight tube pressure-balanced expansion joint

Abstract

This invention provides a compound tie-rod straight pipe pressure-balanced expansion joint, comprising a universal ball joint assembly and a first working bellows, a first intermediate pipe, a balancing bellows, a second working bellows, a third working bellows, and a second end pipe connected in sequence. One end of the universal ball joint assembly is connected to the first intermediate pipe, and the other end is connected to the second end pipe. The universal ball joint assembly can swing along any radial direction of the straight pipe pressure-balanced expansion joint to compensate for displacement of the straight pipe pressure-balanced expansion joint in any radial direction. This invention not only ensures the axial displacement compensation capability of the straight pipe pressure-balanced expansion joint, but also improves its lateral displacement (i.e., radial displacement) compensation capability, thereby improving the universal displacement compensation capability of the straight pipe pressure-balanced expansion joint. It can efficiently cope with the needs of various complex displacement conditions in the piping system, reduce the risk of high stress, and improve the stability of the straight pipe pressure-balanced expansion joint during operation.

Description

Technical Field

[0001] This invention relates to the field of pressure pipeline technology, and in particular to a compound tie rod straight pipe pressure-balanced expansion joint. Background Technology

[0002] Straight pipe pressure-balanced expansion joints are a type of constrained expansion joint, whose main advantage is that they do not transmit pressure thrust to the piping system.

[0003] The existing compound hinged straight pipe pressure-balanced expansion joint consists of parts such as end pipe A1, working bellows A2, hinge plate assembly A3, balance bellows A4, intermediate pipe A5, pin A6, and vertical plate A7, as shown in the figure. Figure 1 As shown, this structure can compensate for axial displacement and lateral displacement (also known as radial displacement) in a single plane, but it cannot meet the working conditions requiring lateral displacement in any plane.

[0004] The existing double universal hinge straight pipe pressure-balanced expansion joint consists of parts such as end pipe A1, working bellows A2, hinge plate assembly A3, balance bellows A4, intermediate pipe A5, pin A6, vertical plate A7, and universal ring A8, as shown in the figure. Figure 2 As shown, this structure can absorb large combined displacements in both the axial and lateral directions simultaneously. However, the universal joint in this structure is characterized by its complex structure, large size, and heavy weight, resulting in poor economic efficiency for this type of expansion joint.

[0005] Therefore, in the face of the complex displacement requirements and economic requirements of actual piping systems, there is an urgent need for a straight pipe pressure balance expansion joint that can meet the requirements of multiple displacement compensation capabilities and has the characteristics of simple structure, lightweight and economical features. Summary of the Invention

[0006] In view of this, the present invention aims to propose a compound tie rod straight pipe pressure-balanced expansion joint to solve the problem that the existing straight pipe pressure-balanced expansion joint is difficult to cope with various complex displacement conditions in the piping system.

[0007] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0008] A compound tie rod straight tube pressure-balanced expansion joint includes a universal ball joint assembly and a first working bellows, a first intermediate tube, a balancing bellows, a second working bellows, a third working bellows, and a second end tube connected in sequence. One end of the universal ball joint assembly is connected to the first intermediate tube, and the other end is connected to the second end tube. The universal ball joint assembly can swing along any radial direction of the straight tube pressure-balanced expansion joint to compensate for the displacement of the straight tube pressure-balanced expansion joint in any radial direction.

[0009] Furthermore, the universal ball swing arm assembly includes a stepped pull plate, a pull rod, and two ball-cone washer assemblies. One end of the pull rod is connected to the stepped pull plate through the ball-cone washer assembly, and the other end is connected to the second end tube through the ball-cone washer assembly, so that the pull rod can swing freely around either end. The end of the stepped pull plate away from the pull rod is connected to the first intermediate tube.

[0010] Furthermore, the axis of the tie rod is parallel to and coplanar with the central axis of the straight pipe pressure-balanced expansion joint.

[0011] Furthermore, the spherical-conical washer assembly includes a spherical washer and a conical washer, which are capable of relative rotation.

[0012] Furthermore, an annular plate is provided on the outer wall of the second end tube, and the pull rod is connected to the annular plate.

[0013] Furthermore, a vertical plate is provided on the outer wall of the first intermediate tube, and one end of the stepped pull plate is connected to the vertical plate, while the other end is connected to the pull rod.

[0014] Furthermore, the stepped pull plate includes an axial plate and a radial plate. One side of the axial plate is connected to the vertical plate, and the other side is connected to the radial plate. The pull rod is connected to the radial plate.

[0015] Furthermore, the universal ball joint assembly also includes multiple nuts, which are threadedly connected to the pull rod. Nuts are provided on both sides of any one of the ball conical washer assemblies along the axial direction of the pull rod.

[0016] Furthermore, the straight pipe pressure-balanced expansion joint includes a first end pipe, a second intermediate pipe, and a connecting pipe. The first end pipe is connected to the side of the first working bellows away from the first intermediate pipe. One end of the second intermediate pipe is connected to the balancing bellows, and the other end is connected to the second working bellows. One end of the connecting pipe is connected to the second working bellows, and the other end is connected to the third working bellows.

[0017] Furthermore, the straight pipe pressure-balanced expansion joint includes a connecting plate, one end of which is connected to the first end pipe and the other end of which is connected to the second intermediate pipe.

[0018] Compared with the prior art, the compound tie rod straight tube pressure-balanced expansion joint of the present invention has the following advantages:

[0019] The present invention discloses a compound tie-rod straight pipe pressure-balanced expansion joint. By setting a first working bellows, a balancing bellows, a second working bellows, a third working bellows, and a universal ball joint assembly, it can not only ensure the axial displacement compensation capability of the straight pipe pressure-balanced expansion joint, but also improve the lateral displacement (i.e., radial displacement) compensation capability of the straight pipe pressure-balanced expansion joint. This improves the universal displacement compensation capability of the straight pipe pressure-balanced expansion joint, enabling it to efficiently meet the needs of various complex displacement conditions in the piping system, reduce the risk of high stress, and enhance the stability of the straight pipe pressure-balanced expansion joint during operation. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of a compound hinged straight pipe pressure-balanced expansion joint in the prior art.

[0022] Figure 2 This is a schematic diagram of the structure of a duplex universal hinge straight pipe pressure-balanced expansion joint in the prior art.

[0023] Figure 3 This is a schematic diagram of a compound tie rod straight tube pressure balance expansion joint according to an embodiment of the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. First end pipe; 2. Connecting plate; 3. First working bellows; 4. First intermediate pipe; 5. Vertical plate; 6. Balancing bellows; 7. Stepped tie plate; 71. Axial plate; 72. Radial plate; 8. Tie rod; 9. Ball-cone washer assembly; 10. Nut; 11. Ring plate; 12. Third working bellows; 13. Connecting pipe; 14. Second working bellows; 15. Second intermediate pipe; 16. Second end pipe. Detailed Implementation

[0026] The inventive concepts of this application will be described below using terminology commonly used by those skilled in the art to communicate the essence of their work to others skilled in the art. However, these inventive concepts may be embodied in many different forms and should not be construed as limited to the embodiments described herein.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0028] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] To address the problem that existing straight-pipe pressure-balanced expansion joints are ill-suited for handling various complex displacement conditions in piping systems, this embodiment proposes a compound tie-rod straight-pipe pressure-balanced expansion joint, as shown in the attached figure. Figure 3 As shown, the straight pipe pressure-balanced expansion joint includes a universal ball joint assembly and a first working bellows 3, a first intermediate pipe 4, a balancing bellows 6, a second working bellows 14, a third working bellows 12, and a second end pipe 16 connected in sequence. One end of the universal ball joint assembly is connected to the first intermediate pipe 4, and the other end is connected to the second end pipe 16. The universal ball joint assembly can swing along any radial direction of the straight pipe pressure-balanced expansion joint to compensate for the displacement of the straight pipe pressure-balanced expansion joint in any radial direction.

[0030] This application, by setting up a first working bellows 3, a balancing bellows 6, a second working bellows 14, a third working bellows 12, and a universal ball joint assembly, can not only ensure the axial displacement compensation capability of the straight pipe pressure-balanced expansion joint, but also improve the lateral displacement (i.e., radial displacement) compensation capability of the straight pipe pressure-balanced expansion joint. This can improve the universal displacement compensation capability of the straight pipe pressure-balanced expansion joint, efficiently meet the needs of various complex displacement conditions in the piping system, reduce the risk of high stress, and improve the stability of the straight pipe pressure-balanced expansion joint during operation.

[0031] The omnidirectional ball pendulum assembly includes a stepped pull plate 7, a pull rod 8, and two spherical conical washer assemblies 9. One end of the pull rod 8 is connected to the stepped pull plate 7 via the spherical conical washer assembly 9, and the other end is connected to the second end tube 16 via the spherical conical washer assembly 9, allowing the pull rod 8 to swing freely around either end. The end of the stepped pull plate 7 furthest from the pull rod 8 is connected to the first intermediate tube 4. It should be noted that either end of the pull rod 8 can be considered a fixed point, but the pull rod 8 can swing freely around this fixed point at a certain angle and in any direction, which can be understood as a ball pendulum structure.

[0032] By incorporating the tie rod 8 and two ball-cone washer assemblies 9, the universal ball swing arm assembly integrates two free swing positions, enabling swing displacement in any radial direction within the straight pipe pressure-balanced expansion joint. This improves the integration of structural components, reduces the structural complexity of the universal ball swing arm assembly, and also helps reduce its weight. Consequently, the entire straight pipe pressure-balanced expansion joint exhibits significant advantages in terms of economy and structural optimization. Furthermore, the two free swing positions can combine to compensate for displacement in any radial direction within the straight pipe pressure-balanced expansion joint, thus achieving universal displacement compensation capability.

[0033] Preferably, when the straight pipe pressure-balanced expansion joint is in its original state, i.e., without any displacement compensation, the axis of the tie rod 8 is parallel and coplanar with the central axis of the straight pipe pressure-balanced expansion joint. Thus, when there is no displacement compensation in the straight pipe pressure-balanced expansion joint, the universal ball joint assembly does not produce any swing displacement. Once the straight pipe pressure-balanced expansion joint produces displacement in any radial direction, the universal ball joint assembly can swing in the corresponding direction with the straight pipe pressure-balanced expansion joint, providing universal displacement compensation capability that can completely conform to the structure of the straight pipe pressure-balanced expansion joint itself.

[0034] Preferably, two sets of universal ball joint assemblies can be arranged in a symmetrical (or circular array) manner along the circumference of the straight pipe pressure-balanced expansion joint to reduce structural stress. Of course, four or more sets of universal ball joint assemblies can also be arranged; this application does not impose a specific limitation on the number of assemblies.

[0035] The ball-cone washer assembly 9 includes a spherical washer and a conical washer. The spherical washer and the conical washer can rotate relative to each other to form a structure similar to a ball joint, thereby realizing the ball pendulum structure of the pull rod 8.

[0036] Regarding the connection between the pull rod 8 and the second end tube 16, an annular plate 11 is provided on the outer wall of the second end tube 16, and the pull rod 8 is connected to the annular plate 11 through a ball-cone washer assembly 9.

[0037] Regarding the connection between the stepped tie plate 7 and the first intermediate pipe 4, a vertical plate 5 is provided on the outer wall of the first intermediate pipe 4. One end of the stepped tie plate 7 is connected to the vertical plate 5, and the other end is connected to the tie rod 8, while spatially avoiding the outer contour of the balance bellows 6. Thus, while ensuring the displacement compensation function of the straight pipe pressure-balanced expansion joint in any radial direction, it can avoid spatial interference with the balance bellows 6, and can also withstand a certain bending moment and achieve the corresponding force transmission function.

[0038] Specifically, the stepped pull plate 7 includes an axial plate 71 and a radial plate 72. One side of the axial plate 71 is connected to the vertical plate 5, and the other side is connected to the radial plate 72. The pull rod 8 is connected to the radial plate 72. Thus, the stepped pull plate 7 can be regarded as an approximately L-shaped plate to avoid the outer contour of the balancing bellows 6. Of course, the stepped pull plate 7 can also be a ring plate, tube, box, or other structure with an approximately L-shaped cross-section of the side wall.

[0039] The universal ball joint assembly also includes multiple nuts 10, which are threadedly connected to the pull rod 8. Nuts 10 are provided on both sides of any one of the ball-cone washer assemblies 9 along the axial direction of the pull rod 8 for fixed assembly. This allows the pull rod 8 to be fixedly installed with the stepped pull plate 7 and the ring plate 11, and also ensures that the ball-cone washer assemblies 9 at both ends of the pull rod 8 are tightened and limited, preventing the pull rod 8 from moving axially at the ball-cone washer assemblies 9, and instead allowing it to swing, thereby improving the stability of the straight pipe pressure balance expansion joint during operation.

[0040] The straight pipe pressure-balanced expansion joint includes a first end pipe 1, a second intermediate pipe 15, and a connecting pipe 13. The first end pipe 1 is connected to the side of the first working bellows 3 away from the first intermediate pipe 4. One end of the second intermediate pipe 15 is connected to the balancing bellows 6, and the other end is connected to the second working bellows 14. One end of the connecting pipe 13 is connected to the second working bellows 14, and the other end is connected to the third working bellows 12. Thus, the main pipe structure of the straight pipe pressure-balanced expansion joint is composed of the first end pipe 1, the first working bellows 3, the first intermediate pipe 4, the balancing bellows 6, the second intermediate pipe 15, the second working bellows 14, the connecting pipe 13, the third working bellows 12, and the second end pipe 16. This structure not only ensures the axial displacement compensation capability of the straight pipe pressure-balanced expansion joint but also provides sufficient lateral displacement (i.e., radial displacement) space. It can efficiently cope with the needs of various complex displacement conditions in the piping system, reduce the risk of high stress, and improve the stability of the straight pipe pressure-balanced expansion joint during operation.

[0041] The straight pipe pressure balance expansion joint includes a connecting plate 2. One end of the connecting plate 2 is connected to the first end pipe 1, and the other end is connected to the second intermediate pipe 15. Thus, when an external axial displacement acts on the straight pipe pressure balance expansion joint, the connecting plate 2 can compress (or stretch) the balance bellows 6, thereby achieving the purpose of the straight pipe pressure balance expansion joint absorbing axial displacement.

[0042] Regarding the working principle of the entire straight pipe pressure balance expansion joint, during operation, the axial displacement from the outside acts on the first end pipe 1 and is transmitted to the second intermediate pipe 15 through the connecting plate 2. Under the constraint of the connecting plate 2, the balance bellows 6 is compressed (or stretched), achieving the purpose of the straight pipe pressure balance expansion joint absorbing axial displacement. The connecting plate 2 is used to constrain the pressure thrust of the bellows. At the same time, the two free swing positions provided by the universal ball swing arm assembly allow the universal ball swing arm assembly to swing in the corresponding direction when displacement in any radial direction acts on the straight pipe pressure balance expansion joint, enabling the straight pipe pressure balance expansion joint to absorb displacement in any radial direction. The pressure thrust generated by the bellows is constrained by the universal ball swing arm assembly, thereby enabling the straight pipe pressure balance expansion joint described in this application to have universal displacement compensation capability.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A compound tie-rod straight tube pressure-balanced expansion joint, characterized in that, The straight pipe pressure balance expansion joint includes a universal ball joint assembly and a first working bellows (3), a first intermediate pipe (4), a balance bellows (6), a second working bellows (14), a third working bellows (12), and a second end pipe (16) connected in sequence. One end of the universal ball joint assembly is connected to the first intermediate pipe (4), and the other end is connected to the second end pipe (16). The universal ball joint assembly can swing along any radial direction of the straight pipe pressure balance expansion joint to compensate for the displacement of the straight pipe pressure balance expansion joint in any radial direction.

2. The compound tie rod straight tube pressure-balanced expansion joint according to claim 1, characterized in that, The universal ball swing arm assembly includes a stepped pull plate (7), a pull rod (8), and two spherical conical washer assemblies (9). One end of the pull rod (8) is connected to the stepped pull plate (7) through the spherical conical washer assembly (9), and the other end is connected to the second end tube (16) through the spherical conical washer assembly (9), so that the pull rod (8) can swing freely around either end. The end of the stepped pull plate (7) away from the pull rod (8) is connected to the first intermediate tube (4).

3. The compound tie rod straight tube pressure-balanced expansion joint according to claim 2, characterized in that, The axis of the tie rod (8) is parallel to and coplanar with the central axis of the straight pipe pressure balance expansion joint.

4. The compound tie rod straight tube pressure-balanced expansion joint according to claim 2, characterized in that, The spherical-conical washer assembly (9) includes a spherical washer and a conical washer, which are capable of relative rotation.

5. A compound tie rod straight tube pressure-balanced expansion joint according to claim 2, characterized in that, The outer wall of the second end tube (16) is provided with a ring plate (11), and the pull rod (8) is connected to the ring plate (11).

6. A compound tie-rod straight tube pressure-balanced expansion joint according to claim 2, characterized in that, The outer wall of the first intermediate tube (4) is provided with a vertical plate (5), one end of the stepped pull plate (7) is connected to the vertical plate (5), and the other end is connected to the pull rod (8).

7. A compound tie-rod straight tube pressure-balanced expansion joint according to claim 6, characterized in that, The stepped pull plate (7) includes an axial plate (71) and a radial plate (72). One side of the axial plate (71) is connected to the vertical plate (5), and the other side is connected to the radial plate (72). The pull rod (8) is connected to the radial plate (72).

8. A compound tie rod straight tube pressure-balanced expansion joint according to claim 2, characterized in that, The universal ball swing arm assembly also includes multiple nuts (10), which are threadedly connected to the pull rod (8). Along the axial direction of the pull rod (8), nuts (10) are provided on both sides of any ball conical washer assembly (9).

9. A compound tie-rod straight tube pressure-balanced expansion joint according to claim 1, characterized in that, The straight pipe pressure balance expansion joint includes a first end pipe (1), a second intermediate pipe (15), and a connecting pipe (13). The first end pipe (1) is connected to the side of the first working bellows (3) away from the first intermediate pipe (4). One end of the second intermediate pipe (15) is connected to the balance bellows (6), and the other end is connected to the second working bellows (14). One end of the connecting pipe (13) is connected to the second working bellows (14), and the other end is connected to the third working bellows (12).

10. A compound tie rod straight tube pressure-balanced expansion joint according to claim 9, characterized in that, The straight pipe pressure balance expansion joint includes a connecting plate (2), one end of which is connected to the first end pipe (1), and the other end is connected to the second intermediate pipe (15).

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