A support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling.

Abstract

This invention discloses a support and sealing structure for the section of the suspended tube penetrating the ceiling of a boiler heating surface. This structure uses supporting ribs installed beside the suspended tubes, which are then supported on the vertical plate of a high-ceiling sealing structure to bear the weight of the middle section of the tube panel, thus suspending the middle section of the tube panel. This solves the problem of easy cracking and leakage at the section of the suspended tube penetrating the ceiling in the middle section of a "W"-shaped vertical heating surface in existing technologies. This structure eliminates the stress caused by the rotational deformation of the tube panel in the plane at the welded area of ​​the traditional welded sealing structure at the ceiling penetration point, thus structurally solving the problem of easy cracking at this location.

Description

Technical Field

[0001] This invention belongs to the technical field of pressure-bearing component structure of power plant boilers, specifically relating to a support and sealing structure for the part of the boiler heating surface suspension pipe passing through the ceiling. Background Technology

[0002] The "W" type, also known as the double "U" type or "UU" type vertical heat exchanger tube panel, refers to a tube panel structure in which the heat exchanger tubes move down and then up along the working fluid flow path, as shown in the attached figure. Figure 1 As shown. The tube screen segments arranged downwards first (including the horizontal segments connected to them afterward) can be called the inlet segment, the tube screen segments arranged upwards last (including the horizontal segments connected to them beforeward) can be called the outlet segment, and the tube screen segments arranged upwards and then downwards in the middle can be called the intermediate segments. In some "W"-shaped vertical heating surfaces, the intermediate segments do not completely pass through the ceiling at the top. Instead, one or two coils of tubes pass through the ceiling (exiting and then re-entering) to suspend the intermediate tube coils and limit their displacement and deformation. These one or two coils of tubes that exit and then re-enter the ceiling are called suspension tubes. In the prior art, the suspension tubes are generally welded to the high-ceiling sealing plate that passes through the ceiling at the top or welded to the ceiling plate through a sleeve to achieve sealing and load-bearing functions. The structural form of the suspension tubes of the intermediate segment of the "W"-shaped vertical heating surface passing through the ceiling in the prior art is shown in the attached figure. Figure 2 As shown.

[0003] The patent application number 201910907478.5, entitled "A Structure and Modification Method for Preventing Cracking at the Sealing Point of Boiler Tubes Penetrating the Ceiling," addresses the improvement of support, positioning, and sealing at the ceiling penetration points of the inlet or outlet sections of the aforementioned "W"-shaped vertical heating surface tube panel. Since each pipe in the inlet or outlet section penetrates the ceiling, the penetrating structure only bears the weight and operating stress of its own tube coil. Furthermore, due to the interconnected constraints between the tubes, the deformation of the inlet and outlet tube panels during operation is minimal. Therefore, the aforementioned structure is sufficient to meet the support and sealing requirements.

[0004] The suspended pipe in the middle section of the "W"-shaped vertical heating surface must not only suspend the weight of the pipe coil in the middle section but also bear the forces of displacement and deformation of the pipe coil. In existing technologies, these functions are achieved through the fillet weld between the suspended pipe and the high-ceiling sealed roof plate. Therefore, the stress on this fillet weld is quite complex, especially bearing the large cyclic stress caused by the in-plane deformation of the heating surface during boiler start-up and shutdown. Under these stresses, low-cycle fatigue, corrosion fatigue, or stress corrosion cracking are prone to occur. Obviously, the stress on the part of the suspended pipe that extends out of the roof is much greater than that on the inlet and outlet pipes. Therefore, the roof-penetrating structure of patent application number 201910907478.5 cannot meet the requirements for the safe long-term operation of this part of the suspended pipe. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a support and sealing structure for the part of the suspended pipe of the boiler heating surface that passes through the ceiling. This structure solves and eliminates the problem in the prior art where the suspended pipe, which is subjected to a lot of stress, is prone to cracking and leakage at the part of the suspended pipe that passes through the ceiling due to the weight of its own pipe and other pipes connected in parallel, while limiting the displacement and deformation of the middle section of the pipe ring.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A support and sealing structure for the part of the suspended pipe of the boiler heating surface that passes through the ceiling includes a high-crowned sealing vertical plate that passes through the ceiling. The tops of two adjacent high-crowned sealing vertical plates that pass through the ceiling are connected by a high-crowned sealing top plate, and the high-crowned sealing top plate is penetrated by the suspended pipe.

[0008] The two sides of the suspension pipe are supported on the upper end surface of the high crown sealing plate by a support rib plate, and the surfaces of the two support rib plates are on the same plane.

[0009] The supporting stiffener includes a first functional side and a second functional side that are perpendicular to each other. The first functional side is fixedly connected to the suspension pipe, and the second functional side abuts against the upper surface of the high-crowned sealing upright plate.

[0010] A further improvement of the present invention is that:

[0011] Preferably, the first functional side and the outer wall of the suspension pipe are welded together along the generatrix direction of the suspension pipe.

[0012] Preferably, the cross-section of the second functional edge is an arc.

[0013] Preferably, the surfaces of the two supporting stiffeners are perpendicular to the surface of the canopy-penetrating sealing vertical plate.

[0014] Preferably, a stop block is provided on each side of one of the supporting stiffeners, and the stop blocks are fixedly installed on the upper end surface of the through-ceiling high-canopy sealing upright.

[0015] Preferably, the surfaces of the stop block and the supporting rib plate that face each other are outwardly convex arc surfaces.

[0016] Preferably, the upper end of the first functional side and the outer end of the second functional side are connected by a third side; the edge of the third side is an arc, a broken line, or a straight line.

[0017] Preferably, the supporting ribs are arranged in the sealing box, the bottom of the first sealing box enclosure is welded to the top or side of the high crown sealing upright plate, the bottom of the second sealing box enclosure is welded to the upper surface or end of the high crown sealing top plate, and the suspension pipe passes through the sealing box.

[0018] Preferably, the lower half of the sealed box is filled with flexible thermal insulation material, and the upper half of the sealed box is filled with refractory castable.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention discloses a support and sealing structure for the section of a boiler heating surface suspended tube penetrating the ceiling. This structure uses supporting ribs installed beside the suspended tube, which rest on the vertical plate of the high-crowned sealing structure to bear the weight of the middle section of the tube screen, effectively suspending the middle section. The supporting ribs and the vertical plate of the high-crowned sealing structure abut against each other but are not fixedly connected. This structure allows the supporting ribs to rotate with the suspended tube as it rotates within the tube screen plane, eliminating the stress caused by the deformation of the tube screen during rotation in traditional welded sealing structures penetrating the ceiling. Structurally, it solves the problem of easy cracking at the connection between the supporting ribs and the high-crowned sealing plate. This invention has been implemented in two boilers, solving the frequent cracking problem at the ceiling-penetrating sealing section of the suspended tube in the middle section of a "W"-shaped vertical heating surface. This structure can be applied to the construction of new boilers and to the technical modification of suspended tubes penetrating the ceiling where existing technology suffers from cracking and leakage problems.

[0021] Furthermore, the supporting stiffeners and suspension pipes are connected by welding, a connection method that is both robust and easy to implement.

[0022] Furthermore, the bottom of the second functional edge, namely the supporting stiffener, is curved, which facilitates the supporting stiffener to rotate back and forth with the suspension pipe.

[0023] Furthermore, the bottom of the supporting stiffener is curved, and the corresponding stop is also curved, so they can match each other, allowing the stop to better block the movement of the supporting stiffener without restricting its forward and backward rotation.

[0024] Furthermore, the supporting stiffeners are placed in a sealed box, where the flexible insulation material can insulate the supporting stiffeners, and the refractory castable can provide external protection for the supporting stiffeners, preventing them from being subjected to significant impacts. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the "W"-shaped vertical heating surface and its suspension pipe of the present invention.

[0026] Figure 2 This is a schematic diagram of the prior art suspended pipe penetrating the ceiling structure of the present invention;

[0027] (a) Direct welding to the top plate; (b) Welding to the top plate via a sleeve;

[0028] Figure 3A schematic diagram of the support structure for the section where the suspended pipe passes through the ceiling in this invention;

[0029] In this figure, (a) is the front view; and (b) is the A-direction view of (a).

[0030] Figure 4 This is a schematic diagram of the sealing type of the part of the suspension pipe passing through the ceiling according to the present invention;

[0031] Figure (a) is a side view; Figure (b) is a cross-sectional view along direction A of Figure (a).

[0032] Figure 5 This is a schematic diagram of the supporting stiffener of the present invention;

[0033] Among them, (a) is the third side of a right triangle; (b) is the third side of a right trapezoid; (c) is the third side of a right sector with an radian of π / 2; and (d) is the third side of a right arc plate with an radian greater than π / 2.

[0034] Wherein: 1-Suspension pipe; 2-High-crowned sealing vertical plate penetrating the ceiling; 3-Supporting stiffener; 4-Block; 5-First sealing box enclosure; 6-Second sealing box enclosure; 7-Flexible insulation material; 8-Refractory castable; 9-Sealing box; 10-High-crowned sealing top plate penetrating the ceiling; 11-High-crowned seal; 12-Inlet section; 13-Outlet section; 14-Other pipelines; 15-Sleeve; 4-1-First functional side; 4-2-Second functional side; 4-3-Third side. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings:

[0036] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] See Figure 1Suspension pipe 1 is a pipe extending upwards from the middle section of the pipeline. One end of the middle section of the pipeline is connected to the inlet section 12, and the other end is connected to the outlet section 13. The upper part of suspension pipe 1, along with the inlet section 12 and the outlet section 13, passes through the high-ceiling seal 11. The lower part of suspension pipe 1 is connected to the other pipes 14 of the middle pipeline via pipe clamps. The high-ceiling seal 11 includes a vertical plate 2 and a top plate 10. The top plate 10 is located at the upper end of the vertical plate 2. The upper part of suspension pipe 1 passes through the high-ceiling seal vertical plate 2 and exits from the high-ceiling seal top plate 10. Figure 2 As shown in Figure (a), in the prior art, the connection between the through-ceiling high-canopy sealed roof plate 10 and the suspension pipe 1 is mostly directly connected by welding, or as shown in Figure (a). Figure 2 As shown in Figure (b), the suspension pipe 1 is externally fitted with a sleeve 15, which is welded to the high-ceiling sealing plate 10 that passes through the ceiling. The suspension pipe 1, passing through the high-ceiling seal 11, also has to bear the weight of the other intermediate pipes 14 connected to it. At the same time, due to the temperature difference of each pipe ring during operation, the entire heated surface tube screen will... Figure 1 If the suspension pipe 1 is slightly rotated in the front and back direction, and the connection between the suspension pipe 1 and the high-ceiling sealed top plate 10 is still directly welded, cracks are likely to occur at the connection.

[0038] One embodiment of the present invention discloses a support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling, see [link to relevant documentation]. Figure 3 and Figure 4 ( Figure 1 (From left to right cross-section) The suspension pipe 1 can be supported on the upper surface of the canopy-through high-ceiling sealing vertical plate 2 by the support stiffener 3.

[0039] The high-ceiling sealing plate 10 is interrupted at the point where the suspension pipe 1 passes through the ceiling. The suspension pipe 1 is inserted into the high-ceiling sealing plate 2. The outer wall of the suspension pipe 1 is supported on the upper end face of the high-ceiling sealing plate 2 by two opposing support ribs 3. The side of the support rib 3 is flat, and the side of the support rib 3 is fixedly connected to the side wall of the suspension pipe 1. The preferred connection method is welding. The bottom of the support rib 3 abuts against the upper end face of the high-ceiling sealing plate 2. This structure ensures that when the suspension pipe 1 is subjected to force and swings slightly back and forth, the support part of the suspension pipe 1 in the high-ceiling sealing plate 2 will not generate additional stress due to the fixed connection. The bottom of the support rib 3 can sway slightly with the swing of the suspension pipe 1.

[0040] Furthermore, the bottom cross section of the support rib 3 is arc-shaped, which reduces the resistance at the support point when the suspension pipe can swing back and forth around the bottom of the support rib 3.

[0041] Furthermore, the two supporting stiffeners 3 are symmetrical with respect to the axis of the suspension pipe 1, and the included angle between the surfaces of the two supporting stiffeners 3 is 180°. The two supporting stiffeners 3 are essentially on the same plane, which can provide uniform support force to the suspension pipe 1.

[0042] Furthermore, the surface of the supporting stiffener 3 is perpendicular to the length direction of the through-ceiling high-canopy sealing upright 2, which makes the resistance of the suspension pipe 1 smaller when it rotates back and forth.

[0043] Preferred, see Figure 5 The shape of the supporting stiffener 3 can be a right triangle, a right trapezoid, or a right-angled arc plate. All supporting stiffeners 3 include a first functional side 4-1, a second functional side 4-2, and a third side 4-3 connected end-to-end. The first functional side 4-1 and the second functional side 4-2 are perpendicularly connected. The first functional side 4-1 is parallel to the axis of the suspension pipe 1 and is welded to the outer wall of the suspension pipe 1. The second functional side 4-2 is perpendicular to the axis of the suspension pipe 1 and abuts against the upper surface of the through-ceiling high-ceiling sealing vertical plate 2. The third side 4-3 is a free side. The cross-section of the second functional side 4-2 is an arc, and the cross-section is perpendicular to the length direction of the second functional side 4-2.

[0044] Furthermore, the length of the first functional side 4-1 is determined by its connection strength with the suspension pipe 1, and the length of the second functional side 4-2 is determined by the gap between the suspension pipe 1 and the two uprights 2 and the thickness of the uprights.

[0045] One embodiment of the present invention discloses a sealing structure, see [link to relevant documentation]. Figure 4 A suspension pipe 1 and two supporting stiffeners 3 connected to it are uniformly enclosed in a sealed box 9. The sealed box 9 includes four side plates: two opposing first sealed box surround plates 5 and two second sealed box surround plates 6. The two sides of the first sealed box surround plates 5 are welded to the two sides of the two second sealed box surround plates 6, and the two second sealed box surround plates 6 are identical. The four surround plates of the sealed box 9 form a cuboid structure. The bottom of the first sealed box surround plates 5 is welded to the top or side of the high-crowned sealing upright plate 2, and the bottom of the second sealed box surround plates 6 is welded to the top or end of the high-crowned sealing top plate 10. The lower part of the interior of the sealed box 9 is filled with flexible insulation material 7, and refractory castable 8 is poured on top of the flexible insulation material 7. The flexible insulation material 7 and the refractory castable 8 enclose the suspension pipe 1 and the supporting stiffeners 3, thereby achieving a seal at the part where the suspension pipe passes through the ceiling.

[0046] One embodiment of the present invention discloses a limiting structure. In order to prevent the supporting stiffener 3 from shifting when it sways left and right, a stop block 4 is provided on each side of the supporting stiffener 3. The stop block 4 can prevent the stiffener from moving back and forth and allow the suspension pipe 1 to rotate freely around the supporting part of the stiffener in the plane of the pipe screen.

[0047] The working principle of this invention is as follows:

[0048] The above structure utilizes supporting ribs to support the suspended pipe 1, and a sealing structure to meet the sealing requirements at the point where the suspended pipe 1 penetrates the ceiling. This differs from conventional methods. Figure 1 The welding support and sealing method shown combines support and sealing into one. This invention separates the sealing and support connections and achieves them through different structures. While meeting the sealing requirements, it can avoid cracking at the part of the suspension pipe 1 that passes through the ceiling.

[0049] When the suspended pipe 1 is stationary, the supporting stiffener 3 supports the suspended pipe 1 on the high-ceiling sealing vertical plate that passes through the ceiling; when the middle section of the pipe screen rotates back and forth due to thermal deformation and thermal displacement, the suspended pipe can adapt to the thermal deformation and thermal displacement of the pipe screen at the support, and the arc surface at the bottom of the supporting stiffener 3 reduces the resistance to rotation.

[0050] Based on this, stop blocks 4 are set on both sides of the baffle to prevent the supporting stiffener 3 from moving back and forth and to limit its movement.

Claims

1. A support and sealing structure for the portion of a boiler heating surface suspension pipe penetrating the ceiling, characterized in that, It includes a ceiling-penetrating high-ceiling sealing vertical plate (2) and a suspension pipe (1). The tops of two adjacent ceiling-penetrating high-ceiling sealing vertical plates (2) are connected by a ceiling-penetrating high-ceiling sealing top plate (10). The ceiling-penetrating high-ceiling sealing top plate (10) is interrupted at the point where the suspension pipe (1) passes through the ceiling. The suspension pipe (1) passes through the space between the ceiling-penetrating high-ceiling sealing vertical plate (2) and the interrupted ceiling-penetrating high-ceiling sealing top plate (10). The two sides of the suspension pipe (1) are supported by a support rib (3) on the upper end surface of the canopy high crown sealing vertical plate (2), and the surfaces of the two support ribs (3) are on the same plane. The supporting stiffener (3) includes a first functional side (4-1) and a second functional side (4-2) that are perpendicular to each other. The first functional side (4-1) is fixedly connected to the suspension pipe (1), and the second functional side (4-2) abuts against the upper end face of the ceiling-penetrating high-canopy sealing vertical plate (2). The cross-section of the second functional side (4-2) is an arc. The first functional side (4-1) and the outer wall of the suspension pipe (1) are welded together along the generatrix direction of the suspension pipe (1); A stop block (4) is provided on each side of one of the supporting stiffeners (3), and the stop block (4) is fixedly installed on the upper end surface of the through-canopy high-canopy sealing vertical plate (2); The surfaces opposite to the stop block (4) and the supporting rib plate (3) are outwardly convex arc surfaces.

2. The support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling as described in claim 1, characterized in that, The surfaces of the two supporting stiffeners (3) are perpendicular to the surface of the canopy-through high-ceiling sealing upright plate (2).

3. The support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling as described in claim 1, characterized in that, The upper end of the first functional side (4-1) and the outer end of the second functional side (4-2) are connected by a third side (4-3); the edge of the third side (4-3) is an arc, a broken line or a straight line.

4. The support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling according to any one of claims 1-3, characterized in that, The supporting rib plate (3) is set in the sealing box (9). The bottom of the first sealing box enclosure plate (5) is welded to the top or side of the through-ceiling high crown sealing upright plate (2). The bottom of the second sealing box enclosure plate (6) is welded to the upper surface or end of the through-ceiling high crown sealing top plate (10). The suspension pipe (1) passes through the sealing box (9).

5. The support and sealing structure for the portion of the boiler heating surface suspension pipe penetrating the ceiling as described in claim 4, characterized in that, The lower half of the sealed box (9) is filled with flexible insulation material (7), and the upper half of the sealed box (9) is filled with refractory castable (8).

Images