Intensive tube panel structure of waste heat boiler

Abstract

The utility model discloses a waste heat boiler dense tube panel structure which comprises a plurality of tube panel sets arranged at intervals, a header assembly, an anti-vibration device and a connecting assembly, each tube panel set comprises a plurality of heat exchange tubes and a plurality of connecting tubes, the heat exchange tubes are sequentially arranged and communicated with one another, and the connecting tubes are used for being communicated with the heat exchange tubes in the same tube panel set. The anti-vibration device comprises first anti-vibration pieces arranged at the tops of the tube panel sets and at least one second anti-vibration piece arranged at the bottoms of the tube panel sets, and the connecting assembly comprises a plurality of first connecting plates arranged on the side faces of the tube panel sets in parallel and second connecting plates arranged at the bottoms of the tube panel sets. According to the utility model, the heat exchange efficiency and the heat economy can be improved, and the anti-vibration device which is convenient to disassemble is arranged, so that the efficiency of unit equipment can be prevented from being sacrificed during the maintenance operation, and the maintenance operation is convenient.

Description

TECHNICAL FIELD

[0001] The utility model belongs to gas turbine unit design field, more specifically relates to a kind of waste heat boiler dense tube panel structure. BACKGROUND

[0002] In recent years, new gas power plant is increased greatly, and the matched waste heat boiler is generally difficult to overhaul the problem of tube panel in furnace. With the continuous improvement of waste heat boiler steam parameter, for example, H-grade gas turbine matched waste heat boiler pressure is 17.1Mpa, temperature reaches 603℃, and the probability of tube panel header over-temperature burst pipe also increases.

[0003] The tube panel inside the waste heat boiler matched with the current gas turbine unit is very dense, and the maintenance condition of the tube panel is not considered in the factory design, so that the existing waste heat boiler tube panel often appears tube panel leakage and even burst pipe and other problems. Therefore, a waste heat boiler dense tube panel structure capable of solving the above problems is urgently needed. UTILITY MODEL CONTENT

[0004] The main purpose of the utility model is to provide a kind of waste heat boiler dense tube panel structure, which can avoid sacrificing gas turbine unit equipment efficiency and facilitate maintenance.

[0005] To achieve the above purpose, the technical scheme of the utility model is as follows:

[0006] A waste heat boiler dense tube panel structure, comprising a plurality of spaced tube panel groups and header assemblies, further comprising a shockproof device and a connecting assembly, the tube panel group comprises a plurality of heat exchange pipes connected to each other and a plurality of connecting pipes for connecting the heat exchange pipes in the same tube panel group, the shockproof device comprises a first shockproof part arranged at the top of the tube panel group and at least one second shockproof part arranged at the bottom of the tube panel group, and the connecting assembly comprises a plurality of first connecting plates arranged in parallel on the side of each tube panel group and a second connecting plate arranged at the bottom of each tube panel group.

[0007] According to the first aspect embodiment of the utility model, the header assembly comprises an upper header and a lower header arranged at the upper and lower ends of each tube panel group, respectively, and the upper header and the lower header are arranged along the length direction of the corresponding tube panel group.

[0008] According to the first aspect embodiment of the utility model, the connecting assembly further comprises a plurality of fixing pins for connecting the second connecting plate and the lower header, and the plurality of fixing pins are arranged between adjacent connecting pipes, respectively.

[0009] According to the first aspect of the utility model, the upper portion of the upper header is provided with an oxygen removal device, the oxygen removal device comprises an oxygen remover body and a low-pressure steam drum in communication with the oxygen remover body, and the low-pressure steam drum is in communication with the corresponding tube panel group.

[0010] According to the first aspect of the utility model, a medium-pressure steam drum and a high-pressure steam drum are arranged at intervals on one side of the low-pressure steam drum, and the medium-pressure steam drum and the high-pressure steam drum are in communication with the corresponding tube panel group below.

[0011] According to the first aspect of the utility model, a plurality of first downcomer straight pipes are sequentially connected below the low-pressure steam drum, and the other ends of the first downcomer straight pipes are in communication with the corresponding tube panel group.

[0012] According to the first aspect of the utility model, a plurality of second downcomer straight pipes are sequentially connected below the medium-pressure steam drum, and the other ends of the second downcomer straight pipes are in communication with the corresponding tube panel group.

[0013] According to the first aspect of the utility model, a plurality of third downcomer straight pipes are sequentially connected below the high-pressure steam drum, and the other ends of the third downcomer straight pipes are in communication with the corresponding tube panel group.

[0014] According to the first aspect of the utility model, the first connecting plates are arranged at equal intervals, and the front end and the tail end of the first connecting plate are respectively provided with a cylindrical clamping block for connecting the heat exchange pipe.

[0015] According to the first aspect of the utility model, a smoke barrier is arranged between the adjacent tube panel groups.

[0016] The technical solution of the utility model has at least one of the following advantages or beneficial effects:

[0017] The utility model improves the heat exchange efficiency and the thermal economy by arranging a plurality of tube panel groups composed of heat exchange pipes and connecting pipes in communication with each other and arranging the header assembly, and the shockproof device is convenient to disassemble, so that the efficiency of the unit equipment can be avoided to be sacrificed and the maintenance operation is facilitated during the maintenance operation. BRIEF DESCRIPTION OF DRAWINGS

[0018] The utility model will be further described below in combination with the drawings and examples.

[0019] ATTACHMENT Figure 1 It is the overall structure diagram of an embodiment of the utility model;

[0020] ATTACHMENT Figure 2 It is the A-A direction sectional view of an embodiment of the utility model;

[0021] ATTACHMENTFigure 3 B-B direction sectional view of one embodiment of the present application;

[0022] Figure 2 is a schematic view of the present application. Figure 4 C-C direction sectional view of one embodiment of the present application;

[0023] Figure 3 is a schematic view of the present application. Figure 5 Enlarged view of H of one embodiment of the present application. DETAILED DESCRIPTION

[0024] The embodiments of the present application will be described in detail below, examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the present application, and cannot be understood as a limitation of the present application.

[0025] In the description of the present application, it is understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as a limitation of the present application.

[0026] In the description of the present application, the meaning of several is one or more, the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, etc. are understood as including the number. If it is described as first, second, only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0027] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include one or more features.

[0028] In the description of the present application, it is necessary to point out that, unless otherwise explicitly specified and limited, the term "connection" should be understood broadly, for example, it can be fixed connection or movable connection, or detachable connection or non-detachable connection, or integrally connected; can be mechanical connection, or electrical connection or can communicate with each other; can be directly connected, or indirectly connected through intermediate medium, can be the internal communication of two elements, indirect communication or the interaction relationship of two elements.

[0029] The disclosure below provides many different implementations or examples to implement different aspects of the present application.

[0030] Referring to the drawings Figure 1 to the drawings Figure 5 As shown in the drawings, a waste heat boiler dense tube panel structure comprises a plurality of spaced tube panel groups 1, a header assembly, a shockproof device and a connecting assembly 4, smoke gas blocking plates are respectively arranged between adjacent tube panel groups 1, and the tube panel group 1 comprises a plurality of heat exchange tubes 11 and a plurality of connecting pipes for connecting the heat exchange tubes 11 in the same tube panel group 1.

[0031] In an embodiment of the present application, the header assembly comprises an upper header 21 and a lower header 22 arranged at the upper and lower ends of each tube panel group 1, and the upper header 21 and the lower header 22 are respectively arranged along the length direction of the corresponding tube panel group 1.

[0032] In an embodiment of the present application, an oxygen removal device is arranged above the upper header 21, the oxygen removal device comprises an oxygen remover body and a low-pressure steam drum in communication with the oxygen remover body, and the low-pressure steam drum is in communication with the corresponding tube panel group 1. A medium-pressure steam drum and a high-pressure steam drum are arranged at intervals on one side of the low-pressure steam drum, and the medium-pressure steam drum and the high-pressure steam drum are in communication with the corresponding tube panel group 1 below.

[0033] In an embodiment of the present application, a plurality of first downcomer straight pipes are sequentially connected below the low-pressure steam drum, and the other ends of the first downcomer straight pipes are respectively in communication with the corresponding tube panel group 1. A plurality of second downcomer straight pipes are sequentially connected below the medium-pressure steam drum, and the other ends of the second downcomer straight pipes are respectively in communication with the corresponding tube panel group 1. A plurality of third downcomer straight pipes are sequentially connected below the high-pressure steam drum, and the other ends of the third downcomer straight pipes are respectively in communication with the corresponding tube panel group 1.

[0034] In an embodiment of the present application, the shockproof device comprises a first shockproof member 31 arranged at the top of the tube panel group 1 and a second shockproof member 32 arranged at the bottom of the tube panel group 1, and adjacent first shockproof members 31 are arranged in parallel.

[0035] In an embodiment of the present application, the connecting assembly 4 comprises a plurality of first connecting plates 41 arranged in parallel on the side surface of each tube panel group 1, a second connecting plate 42 arranged at the bottom of each tube panel group 1, and a plurality of fixing pins 43 for connecting the second connecting plate 42 and the lower header 22, the plurality of fixing pins 43 are arranged between adjacent connecting pipes, and adjacent first connecting plates 41 are arranged at equal intervals, and the front end and the tail end of the first connecting plate 41 are respectively provided with a cylindrical clamping block for connecting the heat exchange tube 11.

[0036] In one embodiment of the utility model, to ensure the manufacturing quality of the tube panel group 1, the following process measures are taken in manufacturing: 1, the tube assembly adopts rigid fixation and reverse deformation process, and welding shrinkage allowance is reserved. According to the drawing size and the analysis of possible welding deformation, the jig frame is made. Due to the dense welding seam on the assembly, the two ends are shrunk and bent after welding, according to the test and production practice experience, the assembly is reversely deformed before welding, and the reverse deformation amount is controlled at 1.5mm / m according to the experience data. The center distance between the two upper assemblies 21 of the jig frame is pre-added twice the reverse deformation amount of the assembly. Reasonable assembly and welding sequence is selected.

[0037] 2, due to the dense welding seam and large welding shrinkage deformation of the tube panel group 1 structure, in order to reduce the welding deformation of the assembly as much as possible, a construction process is adopted, that is, two welders on one assembly symmetrically weld from the middle to the two ends. In this way, the welding deformation can be partially offset.

[0038] 3, a welding method with low welding line energy is selected. The larger the line energy used in the welding process, the greater the thermal compression plastic deformation generated, so the welding deformation increases. Selecting a welding method with low line energy and welding specification can effectively prevent and reduce deformation, such as using small diameter electrode, small current and small swing multi-layer multi-pass welding.

[0039] In one embodiment of the utility model, the welding process is controlled, that is, the preheating before welding, the hydrogen removal immediately after welding and the heat treatment after welding of the heat exchange tube 11 are strictly controlled during the production, including the following operation steps: the first step is preheating before welding, and the preheating is one of the most effective measures to prevent cold cracking. The purpose and effect of preheating is to slow down the cooling speed of the welded joint, reduce the hardening structure and reduce the internal stress, which can also be beneficial to the escape of hydrogen. And for P91 / T91 material, in order to prevent the generation of delayed cracks, it needs to be preheated above 200 DEG C. The second step is to strictly control the interlayer temperature. The interlayer temperature is controlled at 200 DEG C to 280 DEG C, on the one hand to prevent cold cracking, and on the other hand to prevent grain from being too coarse. The third step is to remove hydrogen immediately after welding. Delayed cracking is mainly related to the diffusion and aggregation of hydrogen. If the welding is cooled soon, hydrogen will not have enough time to escape from the weld, which will cause serious delayed cracking. Immediate hydrogen removal after welding can make the diffused hydrogen fully escape from the weld, which has obvious effect on preventing the generation of delayed cracks. The hydrogen removal treatment temperature is controlled at 275 DEG C, and the time is more than 2h.

[0040] In one embodiment of the utility model, the method of preheating on one side and welding on the other side and simultaneously hydrogen removal treatment can be adopted. The track type ceramic electric heating cover is adopted for preheating, and the preheating temperature is above 200 DEG C (infrared temperature gun is adopted for spot check, and the correctness of the automatic temperature measuring instrument is verified). When welding starts after the heating temperature reaches the preheating temperature, the heating cover can be appropriately moved away for welding. After welding is completed, the heating cover continues to heat the header assembly, and the temperature is controlled at 275 DEG C. The purpose of hydrogen removal is achieved. After welding is completed, the heating cover control program should be set to continue heating for 2h, and the temperature is controlled at 275 DEG C.

[0041] And considering that P91 / T91 steel has a tendency of delayed cracking and the structure of the tube panel group 1, magnetic powder nondestructive flaw detection should be carried out before and after the heat treatment of the weld of the header assembly to ensure the weld quality. The flaw detection after heat treatment is generally carried out after 24 hours.

[0042] In one embodiment of the utility model, the method for internal maintenance of the dense tube panel of the waste heat boiler not only avoids sacrificing the efficiency of the unit equipment, but also saves the maintenance cost and construction period and guarantees the integrity of the finned tube of the tube panel, and specifically comprises the following steps.

[0043] Firstly, the part to be maintained is marked, the connecting pipe corresponding to the lower header 22 is cut and unwelded, and then the lower header 22 at the marked position is sequentially unwelded;

[0044] Secondly, the shockproof device at the bottom of the lower header 22 is unwelded, and then the lower header 22 and the second shockproof part 32 are sequentially taken out after being disassembled;

[0045] Further, the first connecting plate 41 in the middle and below the tube panel group 1 at the marked position is partially unwelded, so that the adjacent heat exchange tube 11 can be horizontally moved;

[0046] Further, the flue gas blocking plate on one side of the tube panel group 1 at the marked position is partially unwelded, so that the part to be maintained can be observed from the side;

[0047] Finally, the heat exchange tube 11 is bent at a bending degree of 10:1, that is, the horizontal displacement length is 1m, and the vertical displacement length is 10m, so that the length of the unwelded tube panel group 1 can support the required space for maintenance.

[0048] Although the embodiments of the utility model have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the utility model, and the scope of the utility model is defined by the claims and their equivalents.

Claims

1. A waste heat boiler dense tube panel structure comprising a plurality of tube panel groups (1) arranged at intervals and a header assembly, characterized in that, Further comprising a shockproof device and a connecting assembly, the tube panel group (1) comprises a plurality of heat exchange tubes (11) and a plurality of connecting tubes for connecting the heat exchange tubes (11) in the same tube panel group (1), the shockproof device comprises a first shockproof part (31) arranged at the top of the tube panel group (1) and at least one second shockproof part (32) arranged at the bottom of the tube panel group (1), and the connecting assembly (4) comprises a plurality of first connecting plates (41) arranged in parallel at the side of each tube panel group (1) and a second connecting plate (42) arranged at the bottom of each tube panel group (1).

2. The waste heat boiler dense tube panel structure according to claim 1, characterized in that: The header assembly comprises an upper header (21) and a lower header (22) arranged at the upper and lower ends of each tube panel group (1), respectively, and the upper header (21) and the lower header (22) are arranged along the length direction of the corresponding tube panel group (1).

3. The waste heat boiler dense tube panel structure according to claim 2, characterized in that: The connecting assembly (4) further comprises a plurality of fixing pins (43) for connecting the second connecting plate (42) and the lower header (22), and the fixing pins (43) are arranged between adjacent connecting tubes.

4. The waste heat boiler dense tube panel structure according to claim 2, characterized in that: An oxygen removal device is arranged above the upper header (21), and the oxygen removal device comprises an oxygen removal device body and a low-pressure steam drum in communication with the oxygen removal device body, and the low-pressure steam drum is in communication with the corresponding tube panel group (1).

5. The waste heat boiler dense tube panel structure according to claim 4, characterized in that: A medium-pressure steam drum and a high-pressure steam drum are arranged on one side of the low-pressure steam drum, and the medium-pressure steam drum and the high-pressure steam drum are in communication with the corresponding tube panel group (1) below.

6. The waste heat boiler dense tube panel structure according to claim 4, characterized in that: A plurality of first downcomer straight pipes are sequentially connected below the low-pressure steam drum, and the other ends of the first downcomer straight pipes are in communication with the corresponding tube panel group (1).

7. The waste heat boiler dense tube panel structure according to claim 5, characterized in that: A plurality of second downcomer straight pipes are sequentially connected below the medium-pressure steam drum, and the other ends of the second downcomer straight pipes are in communication with the corresponding tube panel group (1).

8. The waste heat boiler dense tube panel structure according to claim 5, characterized in that: A plurality of third downcomer straight pipes are sequentially connected below the high-pressure steam drum, and the other ends of the third downcomer straight pipes are in communication with the corresponding tube panel group (1).

9. The waste heat boiler dense tube panel structure according to claim 1, characterized in that: The first connecting plates (41) are arranged at equal intervals between adjacent first connecting plates (41), and the front end and the tail end of the first connecting plate (41) are provided with cylindrical clamping blocks for connecting the heat exchange tubes (11).

10. The waste heat boiler dense tube panel structure according to claim 1, characterized in that: Smoke blocking plates are further arranged between adjacent tube panel groups (1).

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