Finned tube type heat exchanger for hot galvanizing line

Abstract

The utility model discloses a finned tube type heat exchanger for a hot galvanizing line, which comprises a shell, a smoke inlet and a smoke outlet are respectively arranged at two ends of the shell, and a plurality of air ducts arranged side by side are arranged between the smoke inlet and the smoke outlet. A plurality of fin heat exchange tube sets are arranged in the air flue at intervals in the smoke flowing direction, each fin heat exchange tube set is provided with a cold side inlet and a cold side outlet, all heat exchange tubes of the fin heat exchange tube sets are fixed to an upper tube plate and a lower tube plate, the heat exchange tubes are connected through U-shaped elbows, and the fin heat exchange tube sets share the upper tube plate and the lower tube plate. A plurality of fin heat exchange tube groups are inserted into the air duct from top to bottom; the upper tube plate is connected with an equipment flange on the shell through a gasket and a fastener; an expansion joint and an electric air valve are sequentially arranged at the air duct inlet in the smoke flowing direction, and the opening degree of the electric air valve is determined according to the smoke outlet temperature. The heat exchanger is convenient for ash removal, overhaul and maintenance, and solves the problem that the performance of the heat exchanger is reduced due to smoke side dust blockage.

Description

Technical Field

[0001] This utility model relates to heat exchangers, specifically to a finned tube heat exchanger for hot-dip galvanizing lines. Background Technology

[0002] The US Steel process is a commonly used hot-dip galvanizing process. In this process, a heat exchanger cools the exhaust gas from the furnace and recovers its heat. The cooled exhaust gas is used for atmosphere protection in the kiln, thus protecting the galvanized sheet. The US Steel process commonly uses two types of heat exchangers: bare tube and finned tube. Finned tube heat exchangers suffer from reduced heat exchange efficiency due to the accumulation of white dust in the exhaust gas, which prevents the exhaust gas from cooling down and directly leads to substandard galvanized sheets. Furthermore, existing finned tube heat exchangers cannot be disassembled, making cleaning and maintenance inconvenient. Utility Model Content

[0003] Purpose of the utility model: The purpose of this utility model is to provide a finned tube heat exchanger for hot-dip galvanizing lines that is easy to clean and maintain, so as to solve the problem of heat exchanger performance degradation caused by dust blockage on the flue gas side.

[0004] Technical solution: The present invention relates to a finned tube heat exchanger for hot-dip galvanizing lines, comprising a shell with a flue gas inlet and a flue gas outlet at both ends, a duct between the flue gas inlet and the flue gas outlet, and a finned heat exchange tube assembly with a cold-side inlet and a cold-side outlet arranged in the duct. Each heat exchange tube of the finned heat exchange tube assembly is fixed to an upper tube sheet and a lower tube sheet, and the heat exchange tubes are connected by U-shaped elbows. The finned heat exchange tube assembly is inserted into the duct from top to bottom, and the upper tube sheet is detachably connected to the shell.

[0005] Furthermore, the upper tube sheet is connected to the equipment flange on the shell via gaskets and fasteners.

[0006] Furthermore, multiple finned heat exchanger tube assemblies are spaced apart in the air duct along the flue gas flow direction, and the multiple finned heat exchanger tube assemblies share the upper tube sheet and the lower tube sheet.

[0007] Furthermore, the connection between the heat exchange tubes, U-bends, upper tube sheet, and lower tube sheet is achieved by welding.

[0008] Furthermore, an expansion joint is installed at the air duct inlet.

[0009] Furthermore, an electric damper is installed at the inlet of the air duct, and the opening degree of the electric damper is determined according to the flue gas outlet temperature.

[0010] Furthermore, there are multiple air ducts arranged side by side between the flue gas inlet and the flue gas outlet.

[0011] Beneficial effects: Compared with the prior art, this utility model has the following advantages: the finned heat exchange tube assembly can be disassembled and pulled out, which is convenient for cleaning, inspection and maintenance, thereby effectively solving the dust blockage problem when the heat exchanger is used in the hot-dip galvanizing line, and ensuring the heat exchange performance of the heat exchanger. Attached Figure Description

[0012] Figure 1 This is a front view of the finned tube heat exchanger provided in this embodiment of the utility model;

[0013] Figure 2 yes Figure 1 Top view. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings.

[0015] 1. Shell; 2. Flue gas inlet; 3. Expansion joint; 4. Finned heat exchanger tube assembly; 5. Electric damper; 6. Upper tube sheet; 7. Equipment flange; 8. Fasteners; 9. Lower tube sheet; 10. Cold side inlet; 11. Cold side outlet.

[0016] like Figure 1 As shown, this utility model embodiment provides a finned tube heat exchanger for hot-dip galvanizing lines, including a shell 1 with a flue gas inlet 2 and a flue gas outlet at both ends, and three air ducts arranged side by side between the flue gas inlet 2 and the flue gas outlet, such as... Figure 2 As shown.

[0017] A finned heat exchanger tube assembly 4 with a cold-side inlet 10 and a cold-side outlet 11 is installed in the air duct. Each heat exchanger tube in the finned heat exchanger tube assembly 4 is fixed on the upper tube sheet 6 and the lower tube sheet 9, and the heat exchanger tubes are connected by U-shaped elbows. In this embodiment, the connection between the heat exchanger tubes, U-shaped elbows, upper tube sheet 6 and lower tube sheet 9 is achieved by welding.

[0018] The finned heat exchanger tube assembly 4 is inserted into the air duct from top to bottom, and the upper tube sheet 6 is connected to the equipment flange 7 on the shell 1 by gaskets and fasteners 8. In this embodiment, two finned heat exchanger tube assemblies 4 are arranged at intervals along the flue gas flow direction in the air duct, and the two finned heat exchanger tube assemblies 4 share the upper tube sheet 6 and the lower tube sheet 9.

[0019] An expansion joint 3 and an electric air valve 5 are sequentially installed at the inlet of the air duct along the direction of flue gas flow. The opening degree of the electric air valve 5 is determined according to the flue gas outlet temperature to ensure that the outlet flue gas temperature meets the process requirements of the hot-dip galvanizing line.

[0020] In operation, the cold-side medium enters the finned heat exchanger tube assembly 4 through the cold-side inlet 10, absorbs heat from the flue gas side within the heat exchanger tubes, and then flows out through the cold-side outlet 11. When there are multiple finned heat exchanger tube assemblies 4, the cold-side medium flows sequentially through multiple finned heat exchanger tube assemblies 4 in the opposite direction to the flue gas flow (i.e., counter-current heat exchange). Of course, it can also be configured as co-current heat exchange or a combination of co-current and counter-current heat exchange as needed. In this embodiment, the cold-side medium is water. The heated water can be used to clean oil stains from pre-treated steel strips or as domestic hot water in the factory.

[0021] If cleaning, maintenance or repair is required, remove the fastener 8 connecting the upper tube sheet 6 and the equipment flange 7, pull the two finned heat exchanger tube assemblies 4 upwards as a whole, and reinstall them after the cleaning, maintenance or repair work is completed.

Claims

1. A finned tube heat exchanger for a hot-dip galvanizing line, comprising a shell (1) with a flue gas inlet (2) and a flue gas outlet at both ends, a duct between the flue gas inlet (2) and the flue gas outlet, and a finned heat exchange tube assembly (4) with a cold-side inlet (10) and a cold-side outlet (11) disposed in the duct, characterized in that, Each heat exchange tube of the finned heat exchange tube assembly (4) is fixed on the upper tube sheet (6) and the lower tube sheet (9). The heat exchange tubes are connected by U-shaped elbows. The finned heat exchange tube assembly (4) is inserted into the air duct from top to bottom. The upper tube sheet (6) is detachably connected to the shell (1).

2. The finned tube heat exchanger according to claim 1, characterized in that, The upper tube sheet (6) is connected to the equipment flange (7) on the shell (1) by gaskets and fasteners (8).

3. The finned tube heat exchanger according to claim 1, characterized in that, Multiple finned heat exchanger tube groups (4) are arranged at intervals along the flue gas flow direction in the air duct, and the multiple finned heat exchanger tube groups (4) share the upper tube sheet (6) and the lower tube sheet (9).

4. The finned tube heat exchanger according to claim 1, characterized in that, The connection between the heat exchange tubes, U-bends, upper tube sheet (6) and lower tube sheet (9) is made by welding.

5. The finned tube heat exchanger according to claim 1, characterized in that, An expansion joint (3) is installed at the air duct inlet.

6. The finned tube heat exchanger according to claim 1, characterized in that, An electric air valve (5) is installed at the inlet of the air duct. The opening degree of the electric air valve (5) is determined according to the flue gas outlet temperature.

7. The finned tube heat exchanger according to any one of claims 1 to 6, characterized in that, There are multiple air ducts arranged side by side between the flue gas inlet (2) and the flue gas outlet.

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