Expansion joint with compensation and noise reduction functions

Abstract

The invention relates to the technical field of expansion joints, in particular to an expansion joint with compensation and noise reduction functions, which comprises a mounting rack, a sliding sleeve, an outer sleeve, a sealing filler, a hydraulic piston, a control assembly and a trigger assembly, the mounting rack is fixed underground, the outer sleeve is fixedly mounted on the mounting rack, the sliding sleeve is mounted in the outer sleeve, and the sealing filler is mounted in the outer sleeve. The sealing filler is arranged in the outer sleeve, the hydraulic piston is arranged on the outer sleeve and fixedly connected with the mounting frame, the control assembly is connected with the hydraulic piston, and the trigger assembly is arranged on the hydraulic piston. Bending stress is balanced through the hydraulic piston, it is avoided that due to the fact that the sliding sleeve bears off-axis stress for a long time, circumferential stress of a sealing material is uneven, and damage and leakage of a sealing structure of the expansion joint are caused, the maintenance frequency of workers for the sleeve expansion joint is reduced, cost is saved, and the noise reduction function of the sleeve expansion joint is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of expansion joints, in particular to an expansion joint with compensation and noise reduction functions. Background Art

[0002] An expansion joint is an elastic compensation element that can be freely extended and retracted. It has the advantages of reliable operation, good performance, and compact structure. It can compensate for the additional stress caused by temperature difference and mechanical vibration. Therefore, the expansion joint is set on the container shell or pipeline as a flexible structure. It can be used for pipeline noise reduction and vibration reduction and heating by utilizing the effective expansion and deformation of its working body core tube. In order to prevent the pipeline from being deformed or damaged due to thermal elongation or temperature stress when the heating pipeline is heated, it is necessary to set an expansion joint on the pipeline to compensate for the thermal elongation of the pipeline, thereby reducing the stress of the pipe wall and the force acting on the valve or support structure. With the needs of urban development and urban beautification, various pipelines entering the ground have become a major trend. The expansion joints connected to the pipelines should also be buried underground. With the increase of service time, the directly buried pipeline will be affected by thermal stress and ground vibration, causing the pipeline to bend and deform. The expansion joints directly connected to the pipeline will also be subjected to bending stress. At this time, the sliding sleeve inside the expansion joint will be subjected to eccentric stress, resulting in uneven circumferential force on the sealing packing. The side subjected to large bending stress is prone to damage to the sealing structure of the expansion joint, resulting in leakage, which will produce excessive noise.

[0003] In order to prevent the expansion joint from being subjected to bending stress, which will lead to uneven circumferential force on the sealing material, causing leakage of the expansion joint and damage to the sealing structure, and to avoid the generation of excessive noise, the problem of uneven force on the sliding sleeve and the sealing material should be solved. The invention patent with application number CN202121022911.6 provides a uniformly force-bearing pipe expansion joint. The invention arranges a linkage protection support mechanism on the threaded rod. When the expansion joint shrinks and deforms, the linkage protection support mechanism will buffer the force received and distribute the buffering force to various parts of the expansion joint, thereby ensuring that the entire expansion joint body is uniformly stressed during use. However, since this linkage protection support mechanism is directly installed on the outside of the expansion joint, when the expansion joint is buried underground, the mechanism is easily affected by mud and dust, resulting in the mechanism being unable to work normally. When the expansion joint is subjected to bending stress, the linkage protection support mechanism is also difficult to balance the bending stress.

[0004] Therefore, in order to prevent the expansion joint from being subjected to eccentric bending stress, which may lead to uneven circumferential force on the sealing material, leakage and damage to the sealing structure, and thus cause excessive noise during operation of the casing expansion joint, an expansion joint with compensation and noise reduction functions is proposed. Summary of the invention

[0005] The object of the present invention is to provide an expansion joint with compensation and noise reduction functions. In order to prevent the expansion joint from being subjected to eccentric bending stress, which leads to uneven circumferential force on the sealing material, causing leakage and damage to the sealing structure, thereby causing the casing expansion joint to generate excessive noise during operation, a hydraulic piston is arranged on the surface of the outer sleeve. When the sliding sleeve is subjected to bending stress, the hydraulic piston applies pressure to the outer sleeve to balance the bending stress, thereby preventing the sliding sleeve from being subjected to eccentric stress for a long time, which leads to uneven circumferential force on the sealing material, causing damage to the sealing structure of the expansion joint and causing leakage. The number of times the staff needs to repair the casing expansion joint is reduced, costs are saved, and the noise reduction function of the casing expansion joint is guaranteed.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An expansion joint with compensation and noise reduction functions, comprising a mounting frame, an outer sleeve, a sliding sleeve, a sealing filler, a hydraulic piston, a control component, and a trigger component, wherein the mounting frame is fixed underground, the outer sleeve is fixedly mounted on the mounting frame, the sliding sleeve is slidably mounted in the outer sleeve, the sealing filler is arranged at one end inside the outer sleeve, the sealing filler is arranged in an annular shape and wraps one end of the sliding sleeve, one side of the sliding sleeve and one side of the outer sleeve are connected to a water pipe, the water flows from the sliding sleeve to the outer sleeve, four hydraulic pistons are arranged on the outer sleeve, the four hydraulic pistons are fixedly connected to the mounting frame, each of the hydraulic pistons is 90° apart, the interior of the hydraulic piston is divided into a water inlet chamber and a water discharge chamber, the control component is arranged on the outer sleeve, the control component is connected to the hydraulic piston and controls the movement of the hydraulic piston, and the trigger component is triggered by pipeline deformation and drives the hydraulic piston to apply pressure to the outer sleeve.

[0008] The sliding sleeve is slidably installed in the outer sleeve, and the sealing filler fills the gap between the sliding sleeve and the outer sleeve. The sliding sleeve moves in the horizontal direction under the wrapping of the sealing filler, so that the expansion joint works in a sealed environment. Four hydraulic pistons are arranged on the outer sleeve, and the internal structures of the four hydraulic pistons are the same. Each hydraulic piston is 90° apart and is located in the up, down, left and right directions of the outer sleeve on the horizontal plane. The control component is arranged on the outer sleeve and contacts the water flow in the outer sleeve. The bending stress on the sliding sleeve drives the control component, and the control component transports the flowing water to the water inlet chamber. The trigger component is triggered by the deformation of the pipeline and drives the hydraulic piston to apply pressure to the outer sleeve, so as to avoid the sliding sleeve being subjected to eccentric stress for a long time, resulting in uneven circumferential force on the sealing material, causing damage to the sealing structure of the expansion joint and causing leakage, thereby reducing the number of times the staff needs to repair the casing expansion joint, saving costs, and ensuring the noise reduction function of the casing expansion joint.

[0009] Preferably, the control component includes a one-way valve, a control rod, a cone valve core, and a spring. Four one-way valves are provided on the outer sleeve. The four one-way valves have the same internal structure. The four one-way valves are respectively connected to the four hydraulic pistons through water inlet pipes. One end of the one-way valve passes through the outer sleeve and is located inside the outer sleeve. The water inlet pipe is connected to the water inlet chamber. The cone valve core is installed inside the one-way valve. The control rod is arranged inside the one-way valve. The spring is sleeved on the control rod. Two ends of the spring are respectively connected to the cone valve core and the inner wall of the one-way valve. One end of the control rod is fixedly connected to the cone valve core. The other end of the control rod is set to a square shape, and the square part of the control rod is slidably connected to the outer wall of the sliding sleeve.

[0010] When the cam is in a state of being in a state of being deformed, the control rod is pulled out of the way and the cam is moved in a direction close to the axis of the sliding sleeve, and the cone valve core moves in the same direction as the control rod to open the one-way valve, and the water pressure is transmitted to the water inlet chamber through the water inlet pipe to provide driving force for the hydraulic piston. The control component will provide driving force for the hydraulic piston only when one end of the sleeve is always subjected to bending stress. When the expansion joint is subjected to turbulent impact force of water flow or ground vibration, the control component will not open the one-way valve to ensure the working stability of the expansion joint, so that the hydraulic piston applies pressure to the deformed part of the sliding sleeve, and the sealing structure is not damaged due to uneven circumferential force on the sealing material, and the number of maintenance of the expansion joint is reduced, thus saving costs.

[0011] Preferably, the trigger assembly includes a piston rod, a balance tube, a pressure channel, and a pressure tube. One end of the piston rod is configured to be circular and installed inside the hydraulic piston, and the circular end is located between the water inlet chamber and the water discharge chamber. The other end of the piston rod extends out of the hydraulic piston and abuts against the outer wall of the outer sleeve. The balance tube is connected to the water inlet chamber, and the two ends of the balance tube are respectively connected to two hydraulic pistons in opposite positions. The balance tube connects the water inlet chambers of the two hydraulic pistons. Four pressure channels are arranged inside the sliding sleeve, and the four pressure channels are located directly below the hydraulic piston. The pressure channels are configured to be cylindrical and extend to the side wall of the sliding sleeve. A pressure tube is arranged on the pressure channel, and one end of the pressure tube is connected to the hydraulic piston. The pressure tube connects the pressure channel with the water discharge chamber.

[0012] By arranging a piston rod inside the hydraulic piston, the control component transmits the water pressure to the water inlet chamber through the water inlet pipe when the one-way valve is opened. The water pressure in the water inlet chamber provides driving force for the piston rod. The piston rod applies pressure to the outer sleeve to balance the bending stress of the sliding sleeve. When the piston rod on this side applies pressure to the sliding sleeve, the piston rod on the opposite side should shrink and give way to achieve a better stress balancing effect. The balancing pipe connects the two opposite water inlet chambers. The piston rod on the side applying pressure moves toward the axis of the sliding sleeve. The circular end of the piston rod squeezes the water in the drainage chamber to the drainage chamber on the opposite side through the balancing pipe. A pressure channel is provided under each hydraulic piston. The pressure channel is arranged inside the sliding sleeve. When one end of the two sides of the sliding sleeve is subjected to bending stress, the middle part of the sliding sleeve will bend. At this time, one of the two pressure channels in opposite positions will be convex in the horizontal direction and the other will be concave. The pressure channel on the side where the piston rod applies pressure is in a concave state and needs to be contracted to give way. The pressure channel on the side of the piston rod is in a convex state. According to Bernoulli's principle, when water flows through the convex part, the pressure of this part decreases due to the increase in flow rate; when it flows through the concave part, the pressure of this part increases due to the relatively slow flow rate. Therefore, a pressure difference will be generated between the two pressure channels with opposite positions. The pressure channel is connected with the drainage chamber through the pressure pipe, so a pressure difference will also be generated between the two drainage chambers with opposite positions. The piston rod applying pressure can squeeze the water in the drainage chamber into the drainage chamber on the opposite side, the water volume in the drainage chamber on the opposite side increases, and the water volume in the water inlet chamber decreases. The piston rod moves away from the axis of the sliding sleeve to complete the contraction and give way, and the trigger component responds to the control component in time. When water flows through the sliding sleeve to generate a pressure difference, the piston rod on one side applies pressure to balance the bending stress in the expansion joint. The piston rod on the opposite side contracts and gives way to ensure the effect of the piston rod applying pressure, avoids the damage of the sealing structure caused by uneven force on the sliding sleeve, and improves the service life of the expansion joint.

[0013] Preferably, the inner wall of the sliding sleeve is provided with four identical slopes, which are spaced apart on the inner wall of the sliding sleeve, and the slope has a gradient of 2-3°. A water inlet is provided on the slope, and the water inlet connects the pressure channel with the inner cavity of the sliding sleeve.

[0014] Arranging a pressure channel inside the sliding sleeve will increase the wall thickness of the sliding sleeve. By utilizing the increased wall thickness of the sliding sleeve, four identical slopes are arranged on the inner wall of the sliding sleeve. The slope has a gradient of 2-3°. The slope is used to increase the pressure difference effect of the pressure channel. When the sliding sleeve is bent, the slope will make the raised portion inside the sliding sleeve higher and the depressed portion lower. When the water flows through the raised portion, the water pressure increases, and when it passes through the depressed portion, the water pressure decreases. The water in the sliding sleeve enters the pressure channel through the water inlet, thereby increasing the pressure difference between the two pressure channels in opposite positions. The slope of the slope is the same as the direction of the water flow, which can reduce the impact force caused by the turbulent backflow of the water flow when the water flows through, and reduce the noise generated inside the expansion joint.

[0015] Preferably, the sliding sleeve is provided with four identical sliding grooves on one side of the inner part of the outer sleeve, the four sliding grooves are located directly below the four one-way valves, the pressure channel passes through the sliding groove, the cross-section of the sliding groove is C-shaped, and the square part of the control rod is in contact with the upper part of the inner wall of the sliding groove.

[0016] By arranging a sliding groove on the outer wall of the sliding sleeve, the square part of the control rod fits with the upper part of the inner wall of the sliding groove. When the sliding sleeve is subjected to bending stress and bends, the sliding groove pulls the control rod through the inner wall, so that the control rod moves toward the axis of the sliding sleeve in the vertical direction to open the one-way valve. When the expansion joint compensates for the elongation of the pipeline, the sliding sleeve will move left and right in the horizontal direction relative to the outer sleeve. At this time, the square part of the control rod will move in the sliding groove, avoiding the control component from being opened incorrectly when the expansion joint is performing compensation work, thereby improving the stability of the mechanism.

[0017] Preferably, the depth of the sliding groove is 3-4 mm greater than the height of the square part of the control rod, and the distance from the square part of the control rod to the axis of the sliding sleeve is 2-3 mm greater than the distance from the bottom of the sliding groove to the axis of the sliding sleeve.

[0018] By leaving a position in the sliding groove so that the control rod can move in the vertical direction, it is prevented that when the sliding groove on one side pulls the control rod, the control rod on the opposite side presses against the outer wall of the sliding sleeve, causing the control assembly to be unable to open.

[0019] Preferably, a material baffle plate is provided inside the outer sleeve near one side of the sealing filler, the material baffle plate is in contact with the sealing filler, and a circular groove is provided on the other side of the material baffle plate, the radius of the circular groove is larger than the outer radius of the sliding sleeve, and the distance from the top of the circular groove to the axis centerline of the sliding sleeve is larger than the distance from the top of the sliding groove to the axis centerline of the sliding sleeve by 3-4mm.

[0020] The sealing packing is closely fitted to the sliding sleeve through the baffle plate, which improves the sealing effect of the sealing packing and reduces the loss of the sealing packing caused by friction when the sliding sleeve moves left and right in the horizontal direction. The sliding groove can move horizontally in the circular groove to prevent the sliding groove from colliding and interfering with the inner wall of the outer sleeve when the expansion joint compensates for the elongation of the pipeline.

[0021] Preferably, the abutting portion between the piston rod and the outer sleeve is configured as an arc plate, and the arc plates on the four hydraulic pistons wrap the outer sleeve.

[0022] By setting the abutting part between the piston rod and the outer sleeve as an arc plate, the arc plates on the four hydraulic pistons wrap the outer sleeve, and the sliding sleeve is subjected to obvious bending stress in a certain direction. When the hydraulic piston applies pressure to the outer sleeve, the arc plate on this side can apply the pressure evenly to the outer sleeve. The complete wrapping of the arc plate avoids the bending stress on one side from being unbalanced, prevents the sealing material from being subjected to uneven circumferential force, and improves the service life of the sealing material.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. By arranging a hydraulic piston on the surface of the outer sleeve, when the sliding sleeve is subjected to bending stress, the trigger assembly is triggered by the deformation of the pipeline and drives the hydraulic piston to apply pressure to the outer sleeve to balance the bending stress, thereby preventing the sliding sleeve from being subjected to eccentric stress for a long time, resulting in uneven circumferential force on the sealing material, causing damage to the sealing structure of the expansion joint and causing leakage, reducing the number of times the staff need to repair the casing expansion joint, saving costs, and ensuring the noise reduction function of the casing expansion joint.

[0025] 2. By setting the control component on the outer sleeve and connecting it to the hydraulic piston, a driving force is provided for the hydraulic piston. The control component will provide driving force for the hydraulic piston only when one end of the sleeve is subjected to bending stress. When the expansion joint is subjected to the impact of turbulent water flow or ground vibration, the control component will not open the one-way valve to ensure the stability of the expansion joint. The hydraulic piston applies pressure to the deformed part of the sliding sleeve, avoiding damage to the sealing structure caused by uneven circumferential force on the sealing material, reducing the number of maintenance times for the expansion joint and saving costs.

[0026] 3. By setting a trigger component on the hydraulic piston, the trigger component responds to the control component in time. When water flows through the sliding sleeve to generate a pressure difference, the piston rod on one side applies pressure to balance the bending stress in the expansion joint, and the piston rod on the opposite side shrinks to make way to ensure the effect of the piston rod applying pressure, avoid the damage of the sealing structure caused by uneven force on the sliding sleeve, and improve the service life of the expansion joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 It is a schematic diagram of the expansion joint structure of the present invention;

[0029] Figure 3 It is a schematic side view of the expansion joint of the present invention;

[0030] Figure 4 It is a schematic cross-sectional view of the outer sleeve of the present invention;

[0031] Figure 5 A cutaway side view of the outer sleeve of the present invention;

[0032] Figure 6 It is a cut-away side view of the expansion joint of the present invention;

[0033] Figure 7 It is a schematic diagram of the opening of the one-way valve of the present invention;

[0034] Figure 8 It is a schematic diagram of applying pressure to the arc plate of the present invention.

[0035] In the figure: 1. mounting frame; 2. outer sleeve; 21. material baffle plate; 22. circular groove; 3. sliding sleeve; 31. slope; 32. water inlet; 33. sliding groove; 4. sealing packing; 5. hydraulic piston; 51. water inlet chamber; 52. water discharge chamber; 6. control assembly; 61. one-way valve; 62. control rod; 63. cone valve core; 64. spring; 7. trigger assembly; 71. piston rod; 711. arc plate; 72. balance pipe; 73. pressure channel; 74. pressure pipe; 8. water inlet pipe. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be understood that the terms "axial", "inner", "upper", "lower", "left", "right", "horizontal", "one side", "vertical" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0038] See also Figures 1 to 8 The present invention provides an expansion joint with compensation and noise reduction functions, and the technical solution is as follows:

[0039] The expansion joint is connected to the buried pipeline. The long plates at the four ends of the mounting frame 1 are fixedly installed underground by cement pouring. The outer sleeve 2 of the expansion joint is fixedly installed on the mounting frame 1. The sealing filler 4 is arranged at one end inside the outer sleeve 2. The sliding sleeve 3 is slidably installed in the outer sleeve 2 at this end. The sealing filler 4 is arranged in a ring shape to wrap one end of the sliding sleeve 3. The sealing filler 4 fills the gap between the sliding sleeve 3 and the outer sleeve 2. The sliding sleeve 3 moves in the horizontal direction under the wrapping of the sealing filler 4, so that the inside of the expansion joint works in a sealed environment. The left side of the sliding sleeve 3 is connected to the pipeline, and the right side of the outer sleeve 2 is connected to the pipeline. The water flows from the sliding sleeve 3 to the outer sleeve 2. Four hydraulic pistons 5 are arranged on the outer sleeve 2. The hydraulic piston 5 is fixedly connected to the mounting frame 1. The interior of the hydraulic piston 5 is divided into a water inlet chamber 51 and a water discharge chamber 52. The internal structure of the four hydraulic pistons 5 is the same. Each piston is spaced 90° apart and is located at the upper, lower, left and right positions of the outer sleeve 2 on the horizontal plane. A control component 6 is provided on the outer sleeve 2. The control component 6 is connected to the hydraulic piston 5 and can control the movement of the hydraulic piston 5. A trigger component 7 is provided on the hydraulic piston 5. When the trigger component 7 is working, the hydraulic piston 5 applies pressure to the outer sleeve 2. The control component 6 contacts the water flow in the outer sleeve 2, and the control component 6 is driven by the bending stress on the sliding sleeve 3. The control component 6 transports the flowing water to the water inlet chamber 51. The trigger component 7 is triggered by the deformation of the pipeline and drives the hydraulic piston 5 to apply pressure to the outer sleeve 2, so as to avoid the sliding sleeve 3 being subjected to eccentric stress for a long time, resulting in uneven circumferential force on the sealing material, causing damage to the sealing structure of the expansion joint and causing leakage, thereby reducing the number of times the staff needs to repair the casing expansion joint, saving costs, and ensuring the noise reduction function of the casing expansion joint.

[0040] As an embodiment of the present invention, refer to Figures 1 to 8, the control assembly 6 includes a one-way valve 61, a control rod 62, a cone valve core 63, and a spring 64. Four one-way valves 61 are arranged on the outer sleeve 2. The internal structures of the four one-way valves 61 are the same. Each one-way valve 61 is connected to the hydraulic piston 5 through the water inlet pipe 8. The cone valve core 63 is installed inside the one-way valve 61, and the one-way valve 61 can be closed and opened. The control rod 62 is arranged inside the one-way valve 61. One end of the control rod 62 is vertically fixed to the cone valve core 63, and the other end is arranged to be square and extend out of the one-way valve 61. The spring 64 is sleeved on the control rod 62. The two ends of the spring 64 are respectively connected to the cone valve core 63 and the inner wall of the one-way valve 61. One end of the one-way valve 61 is located outside the sleeve and this end is connected to the water inlet chamber 51 through the water inlet pipe 8. The other end of the one-way valve 61 is located inside the outer sleeve 2 and the control rod 62 extends out of this end and is slidably connected to the outer wall of the sliding sleeve 3. When one end of the sliding sleeve 3 is subjected to a large bending stress, the surface of the sliding sleeve 3 When bending deformation occurs, one end of the deformation will pull the control rod 62 to displace the control rod 62 in the vertical direction. At this time, the spring 64 is compressed, and the control rod 62 moves toward the axis direction of the sliding sleeve 3. The cone valve core 63 moves in the same direction as the control rod 62. The cone valve core 63 opens the one-way valve 61. After the one-way valve 61 is opened, the water pressure is transmitted to the water inlet chamber 51 through the water inlet pipe 8, providing a driving force for the hydraulic piston 5. The hydraulic piston 5 works to balance the bending stress. The control component 6 will provide a driving force for the hydraulic piston 5 only when one end of the sleeve is always subjected to bending stress. When the expansion joint is subjected to the impact force of turbulent water flow or ground vibration, the control component 6 will not open the one-way valve 61, so as to ensure the stability of the expansion joint, so that the hydraulic piston 5 applies pressure to the deformed part of the sliding sleeve 3, avoids the damage of the sealing structure caused by uneven circumferential force on the sealing material, reduces the number of maintenance of the expansion joint, and saves costs.

[0041] As an embodiment of the present invention, refer to Figures 1 to 8The trigger assembly 7 includes a piston rod 71, a balance pipe 72, a pressure channel 73, and a pressure pipe 74. One end of the piston rod 71 is set to a circular shape and installed inside the hydraulic piston 5, and the circular end is located between the water inlet chamber 51 and the water discharge chamber 52. The other end of the piston rod 71 extends out of the hydraulic piston 5 and abuts against the outer wall of the outer sleeve 2. The two ends of the balance pipe 72 are respectively connected to the water inlet chambers 51 of the two hydraulic pistons 5 in opposite positions, so that the two water inlet chambers 51 in opposite positions are connected. Four identical pressure channels 73 are arranged inside the sliding sleeve 3. The pressure channels 73 are evenly distributed on the inner wall of the sliding sleeve 3 in an annular shape. The two ends of the pressure pipe 74 are respectively connected to the pressure channel 73 and the hydraulic piston 5, so that the pressure channel 73 is connected to the water discharge chamber 52. When the control component 6 opens the one-way valve 61, the water pressure is transmitted to the water inlet chamber 51 through the water inlet pipe 8. The water pressure in the water inlet chamber 51 provides driving force for the piston rod 71. The piston rod 71 applies pressure to the outer sleeve 2 to balance the bending stress of the sliding sleeve 3. When the piston rod 71 on this side applies pressure to the sliding sleeve 3, the piston rod 71 on the opposite side should shrink and give way to achieve a better stress balance effect. When the hydraulic piston 5 is working to balance the bending stress, the piston rod 71 on the side applying pressure moves toward the axis of the sliding sleeve 3, and the circular end of the piston rod 71 squeezes the water in the drainage chamber 52 into the drainage chamber 52 on the opposite side through the balance pipe 72. When one end on both sides of the sliding sleeve 3 When subjected to bending stress, the middle part of the sliding sleeve 3 will bend under force. At this time, the two pressure channels 73 at opposite positions will also bend due to the force deformation of the sliding sleeve 3. The pressure channel 73 at the side where the piston rod 71 applies pressure is concave in the horizontal direction, and the pressure channel 73 at the side of the piston rod 71 that needs to shrink and make way is convex. According to Bernoulli's principle, when water flows through the convex part, the pressure of the part decreases due to the increase in flow rate; when water flows through the concave part, the pressure of the part increases due to the relatively slow flow rate. Therefore, a pressure difference will be generated between the two pressure channels 73 at opposite positions, and the pressure channel 73 is connected to the drainage chamber 52 through the pressure pipe 74, so the position A pressure difference will also be generated between the two opposite drainage chambers 52. The piston rod 71 that applies pressure can squeeze the water in the drainage chamber 52 into the drainage chamber 52 on the opposite side. The water volume in the drainage chamber 52 on the opposite side increases, and the water volume in the water inlet chamber 51 decreases. The piston rod 71 moves away from the axis of the sliding sleeve 3 to complete the contraction and yielding. The trigger component 7 responds to the control component 6 in a timely manner. When there is a pressure difference caused by water flowing through the sliding sleeve 3, the piston rod 71 on one side applies pressure to balance the bending stress in the expansion joint. The piston rod 71 on the opposite side contracts and yields to ensure the effect of the pressure applied by the piston rod 71, avoids the damage of the sealing structure caused by uneven force on the sliding sleeve 3, and improves the service life of the expansion joint.The abutting part of the piston rod 71 and the outer sleeve 2 is set as an arc plate 711. The arc plates 711 on the four hydraulic pistons 5 wrap the outer sleeve 2. The sliding sleeve 3 is subjected to obvious bending stress in a certain direction. When the hydraulic piston 5 applies pressure to the outer sleeve 2, the arc plate 711 on this side can evenly apply pressure to the outer sleeve 2. The arc plate 711 completely wraps to avoid the bending stress on one side from being unbalanced, prevent the sealing material from being subjected to uneven circumferential force, and improve the service life of the sealing material. ;

[0042] As an embodiment of the present invention, refer to Figures 1 to 8Since the pressure channel 73 is arranged inside the sliding sleeve 3, the wall thickness of the sliding sleeve 3 will be increased. By utilizing the increased wall thickness of the sliding sleeve 3, four identical slopes 31 are arranged on the inner wall of the sliding sleeve 3. Each slope 31 is located above the pressure channel 73. The slope inclination angle is set to 2° with the axis of the sliding sleeve 3 as the reference. A water inlet 32 ​​is opened on the slope 31. The water inlet 32 ​​connects the pressure channel 73 with the inner cavity of the sliding sleeve 3. The slope 31 is used to increase the pressure difference effect of the pressure channel 73. When the sliding sleeve 3 is bent, the slope 31 will make the convex part inside the sliding sleeve 3 higher and the concave part lower. When the water flows through the convex part, the water pressure is increased, and when the water flows through the concave part, the water pressure is reduced. Water flows into the pressure channel 73 through the water inlet 32, thereby strengthening the pressure difference between the two pressure channels 73 in opposite positions, and the slope of the slope 31 is the same as the direction of the water flow, which can reduce the impact force caused by the turbulent backflow of the water flow when the water flows through, and reduce the noise generated inside the expansion joint; four identical sliding grooves 33 are arranged on the side of the sliding sleeve 3 located inside the outer sleeve 2, and the four sliding grooves 33 are located directly below the four one-way valves 61. The pressure pipe 74 passes through the sliding groove 33. The cross-section of the sliding groove 33 is C-shaped, and the control rod 62 can move left and right in the C-shaped opening. The square part of the control rod 62 fits with the upper part of the inner wall of the sliding groove 33. When the sliding sleeve 3 is deformed by bending stress, the sliding groove 33 By pulling the control rod 62 through the inner wall, the control rod 62 moves in the vertical direction toward the axis of the sliding sleeve 3 to open the one-way valve 61. When the expansion joint compensates for the elongation of the pipeline, the sliding sleeve 3 will move left and right in the horizontal direction relative to the outer sleeve 2. At this time, the square part of the control rod 62 will move in the sliding groove 33, avoiding the erroneous opening of the control component 6 when the expansion joint is performing compensation work, thereby improving the stability of the mechanism; the groove depth of the sliding groove 33 is greater than the height of the square part of the control rod 62 by 4 mm, and the distance from the square part of the control rod 62 to the axis center line of the sliding sleeve 3 is greater than the distance from the bottom of the sliding groove 33 to the axis center line of the sliding sleeve 3 by 2 mm. The control rod 62 can move in the sliding groove 33 in the vertical direction to avoid the sliding groove 33 on one side being pulled When the control rod 62 is moved, the control rod 62 on the opposite side presses against the outer wall of the sliding sleeve 3, resulting in the control component 6 being unable to be opened; a material baffle plate 21 is arranged on the side of the outer sleeve 2 near the sealing filler 4, and the material baffle plate 21 makes the sealing filler 4 fit closely with the sliding sleeve 3, thereby improving the sealing effect of the sealing filler 4 and reducing the sealing filler 4 that is lost due to friction when the sliding sleeve 3 moves left and right in the horizontal direction; a circular groove 22 is provided on the other side of the material baffle plate 21, and the radius of the circular groove 22 is greater than the outer radius of the sliding sleeve 3, and the distance from the top of the circular groove 22 to the axis center line of the sliding sleeve 3 is greater than the distance from the top of the sliding groove 33 to the axis center line of the sliding sleeve 3 by 4 mm, thereby preventing the sliding groove 33 from moving and colliding with the inner wall of the outer sleeve 2 when the expansion joint compensates for the elongation of the pipeline.

[0043] Working principle: The buried pipeline is subjected to thermal stress and ground vibration, resulting in bending deformation. The expansion joint directly connected to the pipeline is also subjected to bending stress. When one side of the sliding sleeve 3 in the expansion joint is subjected to greater bending stress, both ends of the sliding sleeve 3 will bend, and the middle part will squeeze the sealing filler 4. At this time, the side of the sliding sleeve 3 subjected to greater bending stress will deform and pull the control rod 62 to move the control rod 62 toward the axis of the sliding sleeve 3. The cone valve core 63 moves in the same direction as the control rod 62, the spring 64 is compressed, and the cone valve core 63 opens the one-way valve 61. After the one-way valve 61 is opened, the water pressure is transmitted to the water inlet chamber through the water inlet pipe 8. 51 provides driving force for the hydraulic piston 5. The pressure channel 73 on this side is in a recessed state, and the pressure channel 73 on the opposite side is in a convex state. When water flows through, a pressure difference is generated between the two pressure channels 73. The piston rod 71 on the side applying pressure squeezes the water in the drainage chamber 52 into the drainage chamber 52 on the opposite side through the balance pipe 72. The water volume in the drainage chamber 52 on the opposite side increases and the water volume in the water inlet chamber 51 decreases. The piston rod 71 on the opposite side moves away from the axis of the sliding sleeve 3. The hydraulic piston 5 on the side applying pressure evenly applies pressure to the outer sleeve 2 through the arc plate 711 to balance the bending stress on the sliding sleeve 3.

[0044] A specific embodiment of the present invention is described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above described embodiment. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments without departing from the principles and ideas of the present invention should still fall within the scope of protection of the present invention.

Claims

1. An expansion joint with compensation and noise reduction functions, characterized in that: The invention comprises a mounting frame (1), an outer sleeve (2), a sliding sleeve (3), a sealing filler (4), a hydraulic piston (5), a control component (6), and a trigger component (7); the mounting frame (1) is fixed underground; the outer sleeve (2) is fixedly mounted on the mounting frame (1); the sliding sleeve (3) is slidably mounted in the outer sleeve (2); the sealing filler (4) is arranged at one end inside the outer sleeve (2); the sealing filler (4) is arranged in an annular shape and wraps around one end of the sliding sleeve (3); one side of the sliding sleeve (3) and one side of the outer sleeve (2) are connected to a water pipe; the water flows from the sliding sleeve (3) to the outer sleeve (2); The sleeve (3) flows to the outer sleeve (2), and four hydraulic pistons (5) are arranged on the outer sleeve (2). The four hydraulic pistons (5) are fixedly connected to the mounting frame (1), and each hydraulic piston (5) is 90 degrees apart. The interior of the hydraulic piston (5) is divided into a water inlet chamber (51) and a water outlet chamber (52). The control component (6) is arranged on the outer sleeve (2), and the control component (6) is connected to the hydraulic piston (5) and controls the movement of the hydraulic piston (5). The trigger component (7) is triggered by pipeline deformation and drives the hydraulic piston (5) to apply pressure to the outer sleeve (2).

2. The expansion joint with compensation and noise reduction functions according to claim 1, characterized in that: The control assembly (6) comprises a one-way valve (61), a control rod (62), a cone valve core (63), and a spring (64). Four one-way valves (61) are arranged on the outer sleeve (2). The four one-way valves (61) have the same internal structure. The four one-way valves (61) are respectively connected to the four hydraulic pistons (5) via water inlet pipes (8). One end of the one-way valve (61) passes through the outer sleeve (2) and is located inside the outer sleeve (2). The water inlet pipe (8) is connected to the water inlet chamber (51). The cone valve core (63) is installed inside the one-way valve (61), the control rod (62) is arranged inside the one-way valve (61), the spring (64) is sleeved on the control rod (62), the two ends of the spring (64) are respectively connected to the cone valve core (63) and the inner wall of the one-way valve (61), one end of the control rod (62) is fixedly connected to the cone valve core (63), the other end of the control rod (62) is set in a square shape, and the square part of the control rod (62) is slidably connected to the outer wall of the sliding sleeve (3).

3. The expansion joint with compensation and noise reduction functions according to claim 1, characterized in that: The trigger assembly (7) comprises a piston rod (71), a balance pipe (72), a pressure channel (73), and a pressure pipe (74); one end of the piston rod (71) is arranged in a circular shape and installed inside the hydraulic piston (5), and the circular end is located between the water inlet chamber (51) and the water discharge chamber (52); the other end of the piston rod (71) extends out of the hydraulic piston (5) and abuts against the outer wall of the outer sleeve (2); the balance pipe (72) is communicated with the water inlet chamber (51), and the two ends of the balance pipe (72) are respectively connected to two hydraulic pistons (5) located opposite to each other. The balance pipe (72) connects the water inlet chambers (51) of the two hydraulic pistons (5). Four pressure channels (73) are arranged inside the sliding sleeve (3). The four pressure channels (73) are located directly below the hydraulic pistons (5). The pressure channels (73) are arranged in a cylindrical shape and extend to the side wall of the sliding sleeve (3). A pressure pipe (74) is arranged on the pressure channel (73). One end of the pressure pipe (74) is connected to the hydraulic piston (5). The pressure pipe (74) connects the pressure channel (73) with the drainage chamber (52).

4. The expansion joint with compensation and noise reduction functions according to claim 3, characterized in that: The inner wall of the sliding sleeve (3) is provided with four identical slopes (31), the four slopes (31) are spaced apart on the inner wall of the sliding sleeve (3), the slope (31) has a gradient of 2-3°, and a water inlet (32) is provided on the slope (31), the water inlet (32) connects the pressure channel (73) with the inner cavity of the sliding sleeve (3).

5. The expansion joint with compensation and noise reduction functions according to claim 2, characterized in that: The sliding sleeve (3) is provided with four identical sliding grooves (33) on one side inside the outer sleeve (2). The four sliding grooves (33) are located directly below the four one-way valves (61). The pressure channel (73) passes through the inside of the sliding groove (33). The cross section of the sliding groove (33) is C-shaped. The square part of the control rod (62) fits with the upper part of the inner wall of the sliding groove (33).

6. The expansion joint with compensation and noise reduction functions according to claim 5, characterized in that: The depth of the sliding groove (33) is 3-4 mm greater than the height of the square portion of the control rod (62), and the distance from the square portion of the control rod (62) to the axis of the sliding sleeve (3) is 2-3 mm greater than the distance from the bottom of the sliding groove (33) to the axis of the sliding sleeve (3).

7. The expansion joint with compensation and noise reduction functions according to claim 5, characterized in that: A material baffle plate (21) is arranged inside the outer sleeve (2) on one side close to the sealing filler (4), the material baffle plate (21) is in contact with the sealing filler (4), a circular groove (22) is provided on the other side of the material baffle plate (21), the radius of the circular groove (22) is greater than the outer radius of the sliding sleeve (3), and the distance from the top of the circular groove (22) to the axis center line of the sliding sleeve (3) is greater than the distance from the top of the sliding groove (33) to the axis center line of the sliding sleeve (3) by 3-4 mm.

8. The expansion joint with compensation and noise reduction functions according to claim 3, characterized in that: The portion where the piston rod (71) abuts against the outer sleeve (2) is configured as an arc plate (711), and the arc plates (711) on the four hydraulic pistons (5) wrap the outer sleeve (2).

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