Protection device for heat exchange tube head of waste heat boiler

Abstract

The utility model provides a waste heat boiler heat exchange tube head protection device, which comprises a waste heat boiler and an inlet tube box fixed at the input end of the waste heat boiler, the waste heat boiler comprises a tube plate and a tube head which are fixedly arranged in a shell, the end part of the tube head is embedded and fixed on the tube plate, and the inlet tube box is fixed at the input end of the waste heat boiler. A protective sleeve is additionally arranged at the end, facing the inlet pipe box, of the pipe head, insulation paper is arranged between the protective sleeve and the pipe head, and a concrete layer pipe plate is additionally arranged on the side, facing the inlet pipe box, of the pipe plate. The ceramic protective sleeve is additionally arranged at the end, facing the inlet pipe box, of the pipe head, the concrete layer pipe plate is additionally arranged at the end, facing the inlet pipe box, of the pipe plate, and the high-temperature-resistant concrete layer is additionally arranged in the inlet pipe box, so that the inlet pipe box, the pipe plate and the pipe head are protected; therefore, high-temperature flue gas is prevented from being in direct contact with the tube head and the tube plate, and the service life of the waste heat boiler can be effectively prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler anti-corrosion, in particular to a heat exchange tube head protection device for a waste heat boiler. Background Art

[0002] As a device for recovering heat from high-temperature gas, waste heat boilers are widely used in chemical, building materials, metallurgy, coking and other industries. It uses high-temperature exhaust gas to heat water, recovers heat, and achieves the purpose of reducing energy consumption. The connection structure between the heat exchange tube head and the tube sheet includes a heat exchange tube head and a tube sheet. Heat exchange tube holes are opened on the tube sheet. The heat exchange tube holes are cylindrical. For easy installation, the diameter of the heat exchange tube holes is usually larger than the diameter of the heat exchange tube head. After the heat exchange tube head passes through the heat exchange tube hole, its end is welded to the tube sheet, so that a circle of gap will be formed between the tube sheet and the heat exchange tube head (the place not welded).

[0003] In order to reduce the high-temperature burning and erosion of the high-temperature flue gas directly on the tube sheet, the inlet end joints of the heat exchange tube and the connecting joints between the tube sheet and the heat exchange tube, a heat exchange tube head thermal protection structure is set at the tube sheet and the heat exchange tube. The structure is: a heat-resistant lining layer of high-strength refractory castable is cast on the surface of the tube sheet, and a corundum double-ceramic sleeve structure is installed on the inlet end head of the heat exchange tube. The corundum double-ceramic sleeve structure consists of an outer porcelain sleeve and an inner porcelain sleeve.

[0004] The heat exchange tube head thermal protection structure of the above structure has the following main defects:

[0005] First, the position of the fillet weld between the tube sheet and the heat exchange tube is located in the front of the contact point between the tube sheet and the heat exchange tube, which is far away from the shell side. Therefore, the thermal stress on the fillet weld is large, which will accelerate the stress corrosion of the shell side medium on the fillet weld. The fillet weld is prone to leakage, has a short service life, and has high maintenance costs.

[0006] Secondly, a certain annular gap needs to be retained between the heat exchange tube and the inner porcelain sleeve. The annular gap is usually around 0.5-2mm. Although it increases the effective thermal resistance value, it also affects the installation of the inner porcelain sleeve. During the installation process, the inner porcelain sleeve is not easy to align, which not only increases the difficulty of installation, but also affects the reliability of the corundum double porcelain sleeve structure after installation. Utility Model Content

[0007] The technical problem to be solved by the utility model is to overcome the defects of the prior art. The utility model proposes a heat exchange tube head protection device for a waste heat boiler to avoid direct contact between high-temperature flue gas and the tube sheet and the tube head, thereby preventing the tube head from being burned and the flue gas from corroding the tube sheet.

[0008] In order to solve the above technical problems, the technical solution adopted by the utility model is: a waste heat boiler heat exchange tube head protection device, including a waste heat boiler and an inlet tube box fixed to the input end of the waste heat boiler, the waste heat boiler includes a tube sheet and a tube head fixedly arranged in an outer shell, the end of the tube head is embedded and fixed on the tube sheet, a protective sleeve is added to the end of the tube head facing the inlet tube box, insulating paper is arranged between the protective sleeve and the tube head, and a concrete layer tube sheet is also added to the side of the tube sheet facing the inlet tube box.

[0009] Furthermore, a tapered section is provided at one end of the protective sleeve facing the inlet pipe box, and the tapered section is embedded and fixed in the concrete layer tube sheet.

[0010] Furthermore, a positioning ring is fixedly provided on the outer edge surface of the protective sleeve, and the positioning ring is fixedly embedded in one end of the concrete layer tube sheet close to the tube sheet.

[0011] Furthermore, a gasket is fixedly provided on the side of the concrete layer tube sheet facing the inlet pipe box.

[0012] Furthermore, the inlet pipe box is fixed to the waste heat boiler as a whole by a flange, and a fiber material layer is added on the inner wall of the inlet pipe box.

[0013] Furthermore, a high temperature resistant concrete layer is provided at one end of the inlet pipe box close to the waste heat boiler, the high temperature resistant concrete layer is provided on the inner side of the fiber material layer, and the gasket faces one side of the inlet pipe box and is bonded to the fiber material layer and the high temperature resistant concrete layer.

[0014] Furthermore, the tube sheet is also cast with high temperature resistant concrete, and aluminum silicate wool is added in the high temperature resistant concrete layer and the tube sheet.

[0015] Compared with the prior art, the beneficial effects of the utility model include: by adding a ceramic protective sleeve on the end of the pipe head facing the inlet pipe box, adding a concrete layer tube sheet based on the tube sheet facing the end of the inlet pipe box, and adding a high-temperature resistant concrete layer in the inlet pipe box, the inlet pipe box, tube sheet and pipe head are protected, thereby avoiding direct contact between high-temperature flue gas and the pipe head and tube sheet, which can effectively improve the service life of the waste heat boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The disclosure of the present invention is described with reference to the accompanying drawings. It should be understood that the drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the accompanying drawings, the same reference numerals are used to refer to the same components. Among them:

[0017] Figure 1The overall cross-sectional structure of the heat exchange tube head protection device of the waste heat boiler is schematically shown;

[0018] Figure 2 The schematic diagram shows the locally enlarged structure of the protective sleeve and the heat exchange tube.

[0019] Numbers in the figure: 1-waste heat boiler, 2-inlet pipe box, 3-shell, 4-tube sheet, 5-heat exchange tube, 6-protective sleeve, 7-insulating paper, 8-concrete layer tube sheet, 9-positioning ring, 10-gasket, 11-fiber material layer, 12-high temperature resistant concrete layer. DETAILED DESCRIPTION

[0020] It is easy to understand that according to the technical solution of the utility model, without changing the essential spirit of the utility model, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the utility model, and should not be regarded as the entirety of the utility model or as a limitation or restriction to the technical solution of the utility model.

[0021] Figure 1 The overall cross-sectional structure of the heat exchange tube head protection device of the waste heat boiler is schematically shown. Figure 1 As shown, it includes a waste heat boiler 1 and an inlet pipe box 2 fixed to the input end of the waste heat boiler 1. The aforementioned waste heat boiler 1 includes a tube sheet 4 and a heat exchange tube 5 fixedly arranged in an outer shell 3. The end of the heat exchange tube 5 is embedded and fixed on the tube sheet 4. A protective sleeve 6 is added to the end of the heat exchange tube 5 facing the inlet pipe box 2. The protective sleeve 6 is provided with a tapered section at the end facing the inlet pipe box 2. The tapered section is embedded and fixed in the concrete layer. By arranging the aforementioned ceramic protective sleeve 6, high-temperature flue gas enters the heat exchange tube 5 through the ceramic protective sleeve 6, which can prevent the flue gas from directly scouring the heat exchange tube 5. The tapered section of the ceramic protective sleeve 6 can guide the flue gas and avoid the corrosion of the tube sheet 4 by the flue gas to a certain extent.

[0022] Figure 2 The schematic diagram shows the partial enlarged structure of the protective sleeve and the heat exchange tube. Figure 2As shown, in order to ensure the close combination of the protective sleeve 6 and the heat exchange tube, an insulating paper 7 is arranged between the protective sleeve 6 and the heat exchange tube 5, and the insulating paper 7 is against the protective sleeve 6 and the heat exchange tube 5, and is used to fill the gap between the protective sleeve 6 and the heat exchange tube 5. In order to further improve the combination of the protective sleeve 6 and the heat exchange tube, a concrete layer tube sheet 8 is also provided on the side of the tube sheet 4 facing the inlet tube box 2, and a positioning ring 9 is fixedly provided on the outer edge of the protective sleeve 6. The positioning ring 9 is fixedly embedded in one end of the concrete layer tube sheet 8 close to the tube sheet 4, and the expansion amount of the outer side of the ceramic protective sleeve 6 is basically the same as that of the concrete layer tube sheet 8, so as to ensure that the ceramic protective sleeve 6 does not fall off.

[0023] The aforementioned inlet pipe box 2 is fixed to the waste heat boiler 1 by flanges, and a fiber material layer 11 is added to the inner wall of the inlet pipe box 2. A high temperature resistant concrete layer 12 is also provided at the end of the inlet pipe box 2 close to the waste heat boiler 1. The high temperature resistant concrete layer 12 is provided on the inner side of the fiber material layer 11, and the gasket 10 faces the side of the inlet pipe box 2 and fits with the fiber material layer 11 and the high temperature resistant concrete layer 12. The aforementioned tube sheet 4 is also cast with high temperature resistant concrete, and aluminum silicate wool is also added to the high temperature resistant concrete layer 12 and the tube sheet 4. After such arrangement, the high temperature flue gas enters the waste heat boiler 1 through the inlet pipe box 2, which can prevent the metal from being heated to high temperature, thereby ensuring the mechanical properties of the material and effectively preventing the heat exchange tube 5 from being burned. In addition, due to the presence of the lining and the concrete layer tube sheet 8 provided in the inlet pipe box 2, in combination with the ceramic protective sleeve 6, the high temperature flue gas does not directly contact the tube sheet 4, which can effectively prevent the flue gas from corroding the tube sheet 4. It is worth noting that a fire-resistant and high-temperature resistant gasket 10 is fixedly provided on the side of the concrete layer tube sheet 8 facing the inlet pipe box 2 .

[0024] The technical scope of the present invention is not limited to the contents described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical concept of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A heat exchange tube head protection device for a waste heat boiler, characterized in that: The invention comprises a waste heat boiler (1) and an inlet tube box (2) fixed to the input end of the waste heat boiler (1), wherein the waste heat boiler (1) comprises a tube sheet (4) and a heat exchange tube (5) fixedly arranged in an outer shell (3), wherein the end of the heat exchange tube (5) is embedded and fixed on the tube sheet (4), a protective sleeve (6) is added to the end of the heat exchange tube (5) facing the inlet tube box (2), an insulating paper (7) is provided between the protective sleeve (6) and the heat exchange tube (5), and a concrete layer tube sheet (8) is added to the side of the tube sheet (4) facing the inlet tube box (2).

2. The heat exchange tube head protection device for a waste heat boiler according to claim 1, characterized in that: The protective sleeve (6) is provided with a tapered section at one end facing the inlet pipe box (2), and the tapered section is embedded and fixed in the concrete layer pipe plate (8).

3. The heat exchange tube head protection device for a waste heat boiler according to claim 2, characterized in that: A positioning ring (9) is fixedly arranged on the outer edge surface of the protective sleeve (6), and the positioning ring (9) is fixedly embedded in one end of the concrete layer tube sheet (8) close to the tube sheet (4).

4. The heat exchange tube head protection device for a waste heat boiler according to claim 1, characterized in that: A gasket (10) is fixedly arranged on the side of the concrete layer tube plate (8) facing the inlet tube box (2).

5. The heat exchange tube head protection device for a waste heat boiler according to claim 4, characterized in that: The inlet pipe box (2) and the waste heat boiler (1) are fixed as a whole by flanges, and a fiber material layer (11) is added on the inner wall of the inlet pipe box (2).

6. The heat exchange tube head protection device for a waste heat boiler according to claim 5, characterized in that: A high temperature resistant concrete layer (12) is also provided at one end of the inlet pipe box (2) close to the waste heat boiler (1); the high temperature resistant concrete layer (12) is provided on the inner side of the fiber material layer (11); the gasket (10) faces the side of the inlet pipe box (2) and is in contact with the fiber material layer (11) and the high temperature resistant concrete layer (12).

7. The heat exchange tube head protection device for a waste heat boiler according to claim 6, characterized in that: The tube sheet (4) is also cast with high temperature resistant concrete, and aluminum silicate wool is also added in the high temperature resistant concrete layer (12) and the tube sheet (4).

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