Boiler vibration eliminating device, eliminating system and eliminating device mounting method

Abstract

The invention discloses a boiler vibration eliminating device and system and an eliminating device installation method, and relates to the technical field of power plant boiler maintaining.The boiler vibration eliminating device comprises a partition plate assembly, the partition plate assembly comprises U-shaped steel, stabilizing blocks and partition plates, the U-shaped steel is movably installed outside a low-temperature superheater heat exchange pipe, and the partition plates are installed at the ends of the U-shaped steel; the stabilizing block is fixed between the heat exchange tube and the partition plate and in the boiler flue; the low-temperature superheater pipeline is longitudinally arranged and mounted in the boiler flue, and the low-temperature superheater pipeline comprises a heat exchange pipe and connecting bent pipes connected to the two ends of the heat exchange pipe; a plurality of first anti-vibration sets are arranged on the heat exchange pipe in the axis direction of the heat exchange pipe, and each first anti-vibration set comprises a plurality of partition plate assemblies. Wherein the first anti-vibration sets extend from the center line of the boiler flue to the two sides of the connecting bent pipe and are symmetrically arranged, and the problem that the service life of a boiler flue gas pipeline can be shortened due to vibration generated by eddy current in an existing boiler is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power plant boiler maintenance, and in particular to a boiler vibration eliminating device, an eliminating system and an eliminating device installation method. Background Art

[0002] When the flue gas flow in the boiler passes over the cylindrical obstacle, the flue gas tail flow behind the obstacle no longer presents a regular stratified flow, but instead presents a periodic, regular, and obvious vortex rotating in clockwise and counterclockwise directions.

[0003] The vortex is shed in a uniform and periodic state. This phenomenon is called "Karman vortex". The periodic shedding of air vortex will stimulate a frequency with a certain difference between each phase. The alternating shedding of vortices on both sides of the tube or tube group causes the alternation of forces acting on the tube in the vertical direction of the airflow. When the vortex shedding frequency is close to or coincides with the natural frequency of the standing wave of the fluid medium, it may cause the furnace wall to vibrate, and strong noise and flue gas flow pressure will increase.

[0004] When the structure size is large, it may also cause the natural frequency of the furnace wall to overlap with the natural frequency of the standing wave, thus damaging the structure. Similar to the example of a small hammer hitting a simple pendulum, using a small hammer to apply a very small force to the simple pendulum at the natural frequency of the simple pendulum can make the pendulum swing more intense. If this small force is applied to each cycle of the simple pendulum, the amplitude will continue to increase. As the boiler load increases, the vortex shedding frequency gradually increases. When the vortex shedding frequency is the same as a certain order of natural frequency in the flue, and the boiler load is maintained at this time, the furnace wall will vibrate. Summary of the invention

[0005] In view of the problem that the vibration caused by eddy current in the above-mentioned existing boiler will reduce the service life of the boiler flue gas pipeline, the present invention is proposed.

[0006] Therefore, the object of the present invention is to provide a boiler vibration elimination device, an elimination system and an elimination device installation method, the purpose of which is to eliminate vibration and increase the service life of the boiler flue.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a boiler vibration elimination device, which includes a partition assembly, including a U-shaped steel, a stabilizing block and a partition, the U-shaped steel is movably installed outside the low-temperature superheater heat exchange tube, the partition is installed at the end of the U-shaped steel, and the stabilizing block is fixed between the heat exchange tube and the partition.

[0008] As a preferred solution of the boiler vibration elimination device of the present invention, the U-shaped steel includes a symmetrically horizontally arranged fixing plate and a U-shaped clamping plate connecting the fixing plate, and the heat exchange tube is placed in the middle of the U-shaped steel.

[0009] As a preferred solution of the boiler vibration elimination device of the present invention, the stabilizing block is slidably sleeved on the outside of the fixed plate, and cooperates with the U-shaped clamp to clamp and fix the heat exchange tube, and a gasket is clamped and fixed between the stabilizing block and the heat exchange tube; the partition is fixed to the end of the fixed plate away from the U-shaped clamp by bolts.

[0010] In order to solve the above technical problems, the present invention also provides the following technical solutions: a boiler vibration elimination system, which includes the above-mentioned boiler vibration elimination device, and also includes a boiler flue; a low-temperature superheater pipe, the low-temperature superheater pipe is longitudinally arranged and installed in the boiler flue, and the low-temperature superheater pipe includes a heat exchange tube and a connecting elbow connected at both ends thereof; the heat exchange tube is provided with a plurality of first vibration isolation groups along its axial direction, and each first vibration isolation group contains a plurality of baffle assemblies; wherein the first vibration isolation group extends from the center line of the boiler flue to both sides of the connecting elbow and is symmetrically arranged.

[0011] As a preferred solution of the boiler vibration elimination system of the present invention, wherein: the inner wall of the boiler flue is provided with a first zone, a second zone, a third zone and a fourth zone, and the distances between adjacent zones are equal; the straight line where the first zone and the second zone are located is the first direction line, the straight line where the third zone and the fourth zone are located is the second direction line, the first direction line intersects the second direction line vertically, and the intersection point is located on the center line of the boiler flue.

[0012] As a preferred solution of the boiler vibration elimination system of the present invention, the heat exchange tube is parallel to the first direction line, the first vibration isolation group is arranged along the first direction line, and the partition assembly in each first vibration isolation group is parallel to the second direction line.

[0013] As a preferred solution of the boiler vibration elimination system of the present invention, several groups of partition assemblies in the first vibration isolation group close to the third position area together form a second vibration isolation group, and the second vibration isolation group is arranged from the third position area to the center line of the boiler flue; a first vibration isolation zone is formed between the center line of the boiler flue and the third position area, and a second vibration isolation zone is formed between the center line of the boiler flue and the fourth position area, and the first vibration isolation zone and the first vibration isolation group or the second vibration isolation group in the second vibration isolation zone are symmetrically arranged.

[0014] As a preferred solution of the boiler vibration elimination system of the present invention, the distance between adjacent second vibration isolation groups decreases from the third position area to the center line of the boiler flue.

[0015] As a preferred solution of the boiler vibration elimination system of the present invention, no baffle assembly is installed on a group of low-temperature superheater pipes located in the innermost layer of the boiler flue.

[0016] In order to solve the above technical problems, the present invention also provides the following technical solutions: a method for installing a boiler vibration elimination device, which includes the above-mentioned boiler vibration elimination system, and also includes stopping the boiler, moving the scaffolding to the boiler flue exhaust port, and starting to install the partition assembly from the center to both sides; wherein, firstly, the U-shaped steel is sleeved on the outside of the heat exchange tube, and then the stabilizing block is sleeved on the U-shaped steel to complete the preliminary fixation of the U-shaped steel, and finally the partition is installed to ensure that the end faces of each group of partitions are flush; after the installation of the bottom layer of partition assemblies is completed, the scaffolding is raised upwards, and the partition assembly is fixed in the upper layer of heat exchange tubes in the same way; finally, until the last layer of heat exchange tubes is installed, the installation is stopped, the scaffolding is evacuated, and the boiler operation is restarted.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The partition and the heat exchange tube in the present invention can slide against each other, and the overall flatness of the partition is ensured by a stabilizing block, so that the additional force generated by the expansion difference can be eliminated while ensuring the flatness of the partition; the resonant air chamber is divided into smaller air chambers through the isolation of the partition, so that the standing wave natural frequency of the flue is different from the excitation frequency of vortex shedding, so as to achieve the purpose of eliminating the vibration of the boiler flue. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0020] Figure 1 It is a schematic diagram of the installation structure of the boiler vibration elimination device of the present invention.

[0021] Figure 2 It is a schematic diagram of the overall structure of the boiler vibration elimination device of the present invention.

[0022] Figure 3 It is a schematic diagram of the overall structure of the boiler vibration elimination system of the present invention.

[0023] Figure 4 Schematic diagram of the distribution of partition components of the boiler vibration elimination system of the present invention.

[0024] Figure 5 Schematic diagram of the spacing between partition components of the boiler vibration elimination system of the present invention.

[0025] Figure 6 A cross-sectional view from a certain angle of view of a boiler flue of the boiler vibration elimination system of the present invention.

[0026] Figure 7This is a cross-sectional view from another perspective of the boiler flue of the boiler vibration elimination system of the present invention. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0030] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0031] Example 1

[0032] Reference Figure 1 to Figure 7 , which is the first embodiment of the present invention, provides a boiler vibration elimination device, which includes a partition assembly 100, including a U-shaped steel 101, a stabilizing block 102 and a partition 103, the U-shaped steel 101 is movably installed outside the low-temperature superheater heat exchange tube, the partition 103 is installed at the end of the U-shaped steel 101, and the stabilizing block 102 is fixed between the heat exchange tube and the partition 103; wherein the partition assembly 100 is made of 1Cr18Ni9TIi stainless steel as a whole.

[0033] The U-shaped steel 101 includes a fixing plate 101 a symmetrically and horizontally arranged and a U-shaped clamping plate 101 b connected to the fixing plate 101 a , and the heat exchange tube is placed in the middle of the U-shaped steel 101 .

[0034] The fixing plate 101a is a rectangular plate structure, the U-shaped clamping plate 101b is a semi-circular arc-shaped plate, and both ends of the U-shaped clamping plate 101b are fixed to the fixing plate 101a. Furthermore, the entire U-shaped steel 101 is preferably manufactured by integral casting.

[0035] During use, the heat exchange tube can be placed in the U-shaped groove of the U-shaped steel 101, and according to actual needs, the U-shaped steel 101 can slide along the axial direction of the heat exchange tube to adjust its position.

[0036] The stabilizing block 102 is slidably sleeved on the outside of the fixing plate 101a, and cooperates with the U-shaped clamping plate 101b to clamp and fix the heat exchange tube. A gasket 102a is clamped and fixed between the stabilizing block 102 and the heat exchange tube; the partition plate 103 is fixed to the end of the fixing plate 101a away from the U-shaped clamping plate 101b by bolts 103a.

[0037] Among them, a rectangular hole is opened in the middle of the stabilizing block 102, which can facilitate the transmission of the symmetrically horizontally arranged fixing plate 101a. When the stabilizing block 102 is sleeved on the fixing plate 101a, the heat exchange tube can be confined in the U-shaped groove. The gasket 102a can ensure that the fixing plate 101a clamps the heat exchange tube. The partition 103 is detachably fixed to the U-shaped steel 101 by bolts 103a. After installation, the partition 103 forms a blocking surface to prevent the airflow vortex from spreading to both sides, thereby achieving the purpose of eliminating the vibration generated by the vortex.

[0038] Example 2

[0039] Reference Figure 1 to Figure 7 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that it provides a boiler vibration elimination system, which includes the boiler vibration elimination device in the above embodiment, and also includes a boiler flue 200 and a low-temperature superheater pipe 300. The low-temperature superheater pipe 300 is longitudinally arranged and installed in the boiler flue 200. The low-temperature superheater pipe 300 includes a heat exchange tube 301 and a connecting elbow 302 connected at both ends thereof.

[0040] The radial cross-sectional shape of the boiler flue 200 may be circular or rectangular. In this embodiment, for the convenience of explaining the direction, a boiler flue 200 with a rectangular cross-sectional shape is preferably used.

[0041] Furthermore, the low-temperature superheater pipe 300 is a prior art and is a part of the low-temperature superheater. Several groups are stacked in the boiler flue 200. In this embodiment, four groups are preferably installed from top to bottom in the boiler flue 200, and two adjacent groups of low-temperature superheater pipes 300 are interconnected.

[0042] In the actual flue gas emission process, the flue gas flows downward from the top of the boiler flue 200 and finally is discharged from the bottom opening of the boiler flue 200. The heat exchange tube 301 is provided with a plurality of first vibration isolation groups Z1 along its axis, each of which includes a plurality of baffle assemblies 100.

[0043] Reference Figure 4The first vibration isolation group Z1 extends from the center line of the boiler flue 200 to both sides of the connecting elbow 302 and is symmetrically arranged.

[0044] Among them, blocking air chambers with different widths are formed between the first vibration isolation groups Z1, and these air chambers can block the eddy current from generating resonance frequency.

[0045] The inner wall of the boiler flue 200 has a first zone A, a second zone B, a third zone C and a fourth zone D, and the distances between adjacent zones are equal. In this embodiment, a boiler flue 200 with a rectangular cross-section is preferably used, and the first zone A, the second zone B, the third zone C and the fourth zone D are located in the middle of the inner wall of the boiler flue 200 respectively.

[0046] The straight line where the first area A and the second area B are located is the first direction line X1, and the straight line where the third area C and the fourth area D are located is the second direction line X2. The first direction line X1 intersects the second direction line X2 vertically, and the intersection is located on the center line of the boiler flue 200.

[0047] The heat exchange tube 301 is parallel to the first direction line X1, the first vibration isolation group Z1 is arranged along the first direction line X1, and the partition assembly 100 in each first vibration isolation group Z1 is parallel to the second direction line X2.

[0048] Reference Figure 4 Several groups of partition assemblies 100 in the first vibration isolation group Z1 close to the third zone C together form a second vibration isolation group Z2, and the second vibration isolation group Z2 is arranged from the third zone C to the center line of the boiler flue 200.

[0049] A first vibration-proof zone Q1 is formed between the center line of the boiler flue 200 and the third zone C, and a second vibration-proof zone Q2 is formed between the center line of the boiler flue 200 and the fourth zone D. The first vibration-proof zone Q1 and the first vibration-proof group Z1 or the second vibration-proof group Z2 in the second vibration-proof zone Q2 are symmetrically arranged.

[0050] The junction of the first vibration-proof area Q1 and the second vibration-proof area Q2 is an area where smoke vibration is more intense.

[0051] The distance between adjacent second vibration isolation groups Z2 decreases from the third zone C to the center line of the boiler flue 200 .

[0052] The partition plate assembly 100 is not installed on a group of low-temperature superheater tubes 300 located at the innermost layer of the boiler flue 200 .

[0053] During use, in the basic half-wave, the gas on the side walls of the boiler flue 200 located in the third zone C and the fourth zone D does not pulsate, but near the center line of the boiler flue 200, the gas molecules vibrate violently with the maximum amplitude, and the phase difference between the pressure curve and the displacement curve is 90°.

[0054] Furthermore, at the side wall, the pressure fluctuates violently around zero; whereas at the center line of the boiler flue 200, the pressure node does not change significantly over time.

[0055] The full wave has three displacement nodes and two pressure nodes. The relationship between the displacement nodes and the pressure nodes can be explained by Bernoulli's theorem in fluid dynamics. The maximum displacement point corresponds to the minimum pressure point, and the zero displacement point corresponds to the maximum pressure point.

[0056] Reference Figure 4 and Figure 5 When the boiler flue 200 is relatively wide, in order to avoid the appearance of a cavity larger than that which easily causes acoustic vibration, a partition assembly 100 must be installed. In this embodiment, the first vibration isolation group Z1 and the second vibration isolation group Z2 are preferably provided with three groups.

[0057] The distances between the three second vibration isolation groups Z2 are a, b and c, where a is greater than b and greater than c, that is, the distance between two adjacent second vibration isolation groups Z2 decreases.

[0058] During use, the flue gas molecules located at the center line of the boiler flue 200 vibrate most violently. The further they extend to both sides, the lower the vibration intensity of the flue gas molecules. Therefore, the second vibration isolation group located in the middle needs to be more dense to reduce the distance between the flue gas molecules and thus reduce the vibration intensity.

[0059] Since the tail of the boiler flue 200 is a structure that is more prone to resonance, the effect of setting the baffle assembly 100 at the uppermost layer of the boiler flue 200 is relatively poor, and the baffle assembly 100 only needs to be installed near the tail opening of the boiler flue 200.

[0060] The remaining structures are the same as those of Example 1.

[0061] Example 3

[0062] Reference Figure 1 to Figure 7 , which is the third embodiment of the present invention, is different from the second embodiment in that it provides a method for installing a boiler vibration elimination device, which includes the boiler vibration elimination system in the above embodiment, and also includes the following steps:

[0063] The boiler is shut down, and the scaffold is moved to the smoke outlet of the boiler flue 200, and the partition assembly 100 is installed from the center to both sides.

[0064] Among them, after the boiler is shut down, it is necessary to ensure that the temperature in the boiler flue 200 is lower than 60°C to ensure the safety of the installers. The partition assembly 100 can be lifted by the cooperation of a crane and an electric hoist.

[0065] The U-shaped steel 101 is first sleeved on the outside of the heat exchange tube 301, and then the stabilizing block 102 is sleeved on the U-shaped steel 101 to complete the preliminary fixation of the U-shaped steel 101, and finally the partition 103 is installed to ensure that the end faces of each group of partitions 103 are flush.

[0066] It should be noted that, if the gaps between the heat exchange tubes 301 are too narrow in actual situations and it is inconvenient to insert the U-shaped steel 101 into the gaps, it is only necessary to install the U-shaped steel 101 on the topmost heat exchange tube 301 .

[0067] Furthermore, during the installation process, the U-shaped steel 101 can be first inserted from top to bottom between the transversely arranged heat exchange tubes 301, and then the U-shaped clamp 101b is rotated 90° to rotate the vertically inserted fixing plate 101a to a horizontal direction. During this process, the heat exchange tube 301 is always in the U-shaped groove of the U-shaped steel 101.

[0068] Finally, the stabilizing block 102 is sleeved on the fixing plate 101a, and then the partition plate 103 and the fixing plate 101a are fixed by bolts 103a.

[0069] After the installation of the bottom-layer partition assembly 100 is completed, the scaffolding is raised upwards, and the partition assembly 100 is fixed in the upper-layer heat exchange tube 301 in the same way.

[0070] Finally, after the last layer of heat exchange tubes 301 is installed, the installation is stopped, the scaffolding is evacuated, and the boiler is restarted.

[0071] During use, the partition assembly 100 divides the original complete resonant air chamber of the boiler flue 200 into smaller individual air chambers. Due to the change in spatial distance, the standing wave natural frequency of the flue is different from the excitation frequency of eddy current shedding. At this time, the eddy current cannot form a resonant frequency to create vibration, and thus cannot cause the boiler flue 200 to vibrate.

[0072] The remaining structure is the same as that of Example 2.

[0073] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A boiler vibration elimination device, characterized in that: include, The partition assembly (100) comprises a U-shaped steel (101), a stabilizing block (102) and a partition (103), wherein the U-shaped steel (101) is movably installed outside a heat exchange tube of a low-temperature superheater, the partition (103) is installed at the end of the U-shaped steel (101), and the stabilizing block (102) is fixed between the heat exchange tube and the partition (103).

2. The boiler vibration elimination device according to claim 1, characterized in that: The U-shaped steel (101) comprises a fixing plate (101a) symmetrically arranged horizontally and a U-shaped clamping plate (101b) connected to the fixing plate (101a), and the heat exchange tube is cooperatively placed in the middle of the U-shaped steel (101).

3. The boiler vibration elimination device according to claim 2, characterized in that: The stabilizing block (102) is slidably sleeved outside the fixing plate (101a) and cooperates with the U-shaped clamping plate (101b) to clamp and fix the heat exchange tube, and a gasket (102a) is clamped and fixed between the stabilizing block (102) and the heat exchange tube; The partition plate (103) is fixed to an end of the fixing plate (101a) away from the U-shaped clamping plate (101b) by means of bolts (103a).

4. A boiler vibration elimination system, characterized in that: The boiler vibration elimination device according to any one of claims 1 to 3 further comprises: Boiler flue (200); A low-temperature superheater pipe (300), wherein the low-temperature superheater pipe (300) is longitudinally arranged and installed in the boiler flue (200), and the low-temperature superheater pipe (300) comprises a heat exchange pipe (301) and connecting elbows (302) connected at both ends thereof; The heat exchange tube (301) is provided with a plurality of first vibration-proofing groups (Z1) along the axial direction thereof, and each first vibration-proofing group (Z1) includes a plurality of baffle assemblies (100); The first vibration-proof group (Z1) extends from the center line of the boiler flue (200) toward both sides of the connecting elbow (302) and is symmetrically arranged.

5. The boiler vibration elimination system according to claim 4, characterized in that: The inner wall of the boiler flue (200) is provided with a first zone (A), a second zone (B), a third zone (C) and a fourth zone (D), and the distances between adjacent zones are equal; The straight line where the first position area (A) and the second position area (B) are located is a first direction line (X1), the straight line where the third position area (C) and the fourth position area (D) are located is a second direction line (X2), the first direction line (X1) and the second direction line (X2) intersect vertically, and the intersection point is located on the center line of the boiler flue (200).

6. The boiler vibration elimination system according to claim 5, characterized in that: The heat exchange tube (301) is parallel to the first direction line (X1), the first vibration isolation group (Z1) is arranged along the first direction line (X1), and the partition assembly (100) in each first vibration isolation group (Z1) is parallel to the second direction line (X2).

7. The boiler vibration elimination system according to claim 5 or 6, characterized in that: A plurality of baffle assemblies (100) in the first vibration-proofing group (Z1) close to the third position zone (C) together form a second vibration-proofing group (Z2), wherein the second vibration-proofing group (Z2) is arranged from the third position zone (C) to the center line of the boiler flue (200); A first vibration-proof zone (Q1) is formed between the center line of the boiler flue (200) and the third zone (C), and a second vibration-proof zone (Q2) is formed between the center line of the boiler flue (200) and the fourth zone (D). The first vibration-proof zone (Q1) and the second vibration-proof zone (Q2) are symmetrically arranged with the first vibration-proof group (Z1) or the second vibration-proof group (Z2).

8. The boiler vibration elimination system according to claim 7, characterized in that: The distance between adjacent second vibration-proof groups (Z2) decreases from the third position zone (C) to the center line of the boiler flue (200).

9. The boiler vibration elimination system according to claim 8, characterized in that: A group of low-temperature superheater pipes (300) located at the innermost layer of the boiler flue (200) is not equipped with a partition assembly (100).

10. A method for installing a boiler vibration elimination device, characterized in that: The boiler vibration elimination system according to any one of claims 4 to 8 further comprises: Shut down the boiler, move the scaffolding to the smoke outlet of the boiler flue (200), and start installing the partition assembly (100) from the center to both sides; The U-shaped steel (101) is first sleeved on the outside of the heat exchange tube (301), and then the stabilizing block (102) is sleeved on the U-shaped steel (101) to complete the preliminary fixation of the U-shaped steel (101), and finally the partition (103) is installed to ensure that the end surfaces of each group of partitions (103) are flush; After the installation of the bottom-layer baffle assembly (100) is completed, the scaffolding is raised upwards, and the baffle assembly (100) is fixed in the upper-layer heat exchange tube (301) in the same manner; Finally, after the last layer of heat exchange tubes (301) is installed, the installation is stopped, the scaffolding is evacuated, and the boiler is restarted.

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