A support, diversion and leakage prevention structure for the U-bend of a U-tube type cross-flow heat exchanger

Abstract

A support, diversion and leakage prevention structure for the U-bend of a U-tube type cross-flow heat exchanger. The support, diversion and leakage prevention structure mainly includes a diversion support plate, a U-shaped diversion and leakage prevention plate, a support sealing plate and a sealing soft pad; the diversion support plate is installed on the heat exchange tube bundle and is in sliding fit with the guide rail on the inner wall of the heat exchanger shell through the guide rail mounting holes at the lower part of the diversion support plate; the diversion support plate is placed at the front end of the U-bend of the U-shaped heat exchange tube bundle, one end of the U-shaped diversion and leakage prevention plate is connected to the diversion support plate, and the other end is lapped in the U-shaped groove of the support sealing plate through a sealing elastic pad; a lower diversion port is arranged at the lower part of the diversion support plate, and an upper diversion port is arranged at the upper part of the diversion support plate. The invention can not only support the bent pipe section of the U-shaped tube bundle, but also reduce the fluid resistance drop in the shell side, and can also make full use of the heat transfer area of the heat exchange tubes in the U-bend pipe section and improve the heat transfer efficiency of the heat exchanger.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat exchangers, and relates to a support, flow guiding and leakage prevention structure for the U-bend section of a U-tube type cross-flow heat exchanger. Background Art

[0002] As the main heat transfer equipment for small-pressure-drop gas heat exchangers, cross-flow heat exchangers have problems such as shell-side fluid uneven flow, short circuit, and low heat transfer efficiency. Currently, cross-flow heat exchangers are mainly divided into fixed tube sheet heat exchangers, floating head heat exchangers, and U-tube type heat exchangers. The heat exchange tubes of cross-flow fixed tube sheet heat exchangers and floating head heat exchangers are straight tubes. When the shell-side structure is reasonably set, problems such as shell-side fluid uneven flow, short circuit, and low heat transfer efficiency are not serious. However, when using the structure of a U-tube type cross-flow heat exchanger, due to the existence of the U-bend section, the gap between the U-bend tube and the shell head is large, and fluid leakage and short circuit are likely to occur in the shell-side fluid. The commonly used method for preventing leakage and short circuit is to adopt a structure of adding a full support plate in the U-bend section. Although this structure can prevent fluid short circuit in the U-bend section, the full support plate also completely blocks the flow of shell-side fluid to the U-bend section, making the U-bend section not play a heat transfer role, and due to the reduction of the flow area, it also increases the fluid pressure drop and reduces the overall heat transfer efficiency of the heat exchanger. Summary of the Invention

[0003] The present invention provides a support, flow guiding and leakage prevention structure for the U-bend section of a U-tube type cross-flow heat exchanger, which can solve the problems of fluid short circuit or leakage in the U-bend section of the U-tube type cross-flow heat exchanger.

[0004] The object of the present invention is achieved through the following technical solutions:

[0005] A support, flow guiding and leakage prevention structure for the U-bend of a U-tube type cross-flow heat exchanger, which mainly includes a flow guiding support plate, a U-shaped flow guiding and leakage prevention plate, a support sealing plate, and a sealing soft pad; the flow guiding support plate is installed on the heat exchange tube bundle and is in sliding fit with the guide rail on the inner wall of the heat exchanger shell through the guide rail mounting holes at its lower part; the flow guiding support plate is placed at the front end of the U-bend of the U-shaped heat exchange tube bundle, one end of the U-shaped flow guiding and leakage prevention plate is connected to the flow guiding support plate, and the other end is lapped in the U-shaped groove of the support sealing plate through a sealing elastic pad; a lower flow guiding port is provided at the lower part of the flow guiding support plate, and an upper flow guiding port is provided at the upper part.

[0006] The U-shaped flow guiding and leakage prevention area of the U-shaped flow guiding and leakage prevention plate is made to match the U-bend of the U-shaped heat exchange tube bundle of the heat exchanger, and there is a gap of 5-6 mm between the U-shaped flow guiding and leakage prevention plate and the U-shaped heat exchange tube bundle.

[0007] The support sealing plate is provided with a strengthening positioning plate, and the other end of the strengthening positioning plate is connected to the heat exchanger shell.

[0008] The heat exchange tube hole tube bridge on the flow guiding support plate is provided with flow guiding holes.

[0009] The present invention solves the problems of fluid short - circuit or leakage in the U - shaped bend section of a U - tube type cross - flow heat exchanger. It reduces the pressure drop of the shell - side fluid, enables the U - shaped bend section to participate in heat transfer, and increases the heat transfer efficiency of the heat exchanger. On the premise of manufacturing tolerances, the U - tube bundle can still freely expand and contract in the shell after installing the flow - guiding and leakage - preventing structure. The structure of the present invention is compact, simple, convenient for installation and sealing, with low pressure drop and high heat transfer efficiency. Using the U - tube type cross - flow heat exchanger of the present invention, the pressure drop of the shell - side fluid can be reduced by more than 15%, and the heat transfer efficiency of the heat exchanger can be increased by more than 10%. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic structural diagram of the present invention;

[0011] Figure 2 is Figure 1 the top - view sectional drawing of;

[0012] Figure 3 is a U - tube cross - flow heat exchanger with the structure of the present invention;

[0013] Figure 4 is a schematic structural diagram of the flow - guiding support plate of the present invention;

[0014] Figure 5 is a schematic structural diagram of the U - shaped flow - guiding and leakage - preventing plate of the present invention;

[0015] Figure 6 is a schematic structural diagram of the support and sealing plate of the present invention;

[0016] Figure 7 is Figure 6 the side - view sectional drawing of;

[0017] Reference numerals in the drawings: tube box 1, tube - side inlet 2, heat exchanger shell 3, shell - side outlet 4, U - shaped heat - exchange tube bundle 5, support flow - guiding and leakage - preventing structure 6, support 7, shell - side inlet 8, tube - side outlet 9, flow - guiding support plate 10, U - shaped flow - guiding and leakage - preventing plate 11, support and sealing plate 12, sealing elastic pad 13, upper flow - guiding port 14, flow - guiding hole 15, flow - guiding support plate guide rail installation hole 16, lower flow - guiding port 17, flow - guiding support plate heat - exchange tube hole 18, connection end of U - shaped flow - guiding and leakage - preventing plate and flow - guiding support plate 19, U - shaped flow - guiding and leakage - preventing area 20, connection end of U - shaped flow - guiding and leakage - preventing plate and support and sealing plate 21, strengthening positioning plate 22, U - shaped groove 24. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Refer to Figures 1 to 7, a support, diversion and leak prevention structure for the U-bend of a U-tube type cross-flow heat exchanger. The support, diversion and leak prevention structure 6 mainly includes a diversion support plate 10, a U-shaped diversion and leak prevention plate 11, a support sealing plate 12 and a sealing soft pad 13; the diversion support plate 10 is installed on the heat exchange tube bundle and is in sliding fit with the guide rail on the inner wall of the heat exchanger shell through the guide rail installation holes 16 at its lower part, and the peripheral outer edge of the diversion support plate 10 contacts and slides with the inner wall of the shell; the diversion support plate 10 is placed at the front end of the U-bend of the U-shaped heat exchange tube bundle, one end of the U-shaped diversion and leak prevention plate 11 is connected to the diversion support plate 10, and the other end is lapped in the U-shaped groove 24 of the support sealing plate through the sealing elastic pad 13; the front and rear ends of the U-shaped diversion and leak prevention plate 11 are free ends and contact and slide with the inner wall of the shell; a lower diversion port 17 is provided at the lower part of the diversion support plate 10, and an upper diversion port 14 is provided at the upper part. The lower diversion port 17 is conducive to the shell-side fluid flowing into the U-bend pipe section to participate in heat transfer. The upper diversion port 14 is conducive to the fluid flowing out of the U-bend pipe section. The sealing elastic pad 13 is sealed with some soft fillers, such as asbestos, pearl cotton, etc., to form a flexible and telescopic sealing structure, so that the U-shaped diversion and leak prevention plate 11 can freely expand and contract in the U-shaped groove, thereby realizing the free expansion and contraction of the U-shaped tube bundle in the shell and making it difficult for the shell-side fluid to generate leakage flow.

[0020] This structure can direct the shell-side fluid to the U-bend pipe part, enabling the heat exchange tubes in the U-bend part to fully participate in heat exchange. Furthermore, it reduces the pressure drop of the shell-side fluid and increases the heat transfer efficiency of the heat exchanger.

[0021] The U-shaped diversion and leak prevention area 20 of the U-shaped diversion and leak prevention plate 11 is made to match the U-bend of the U-shaped heat exchange tube bundle of the heat exchanger, which can eliminate the influence of manufacturing tolerances and leave a gap of 5-6 mm between it and the U-shaped tube bundle, ensuring the smooth installation of the U-shaped diversion and leak prevention plate and making it difficult for the shell-side fluid to generate leakage flow.

[0022] Reinforcing positioning plates 22 are provided on the support sealing plate 12, and the other ends of the reinforcing positioning plates 22 are connected to the heat exchanger shell. The reinforcing positioning plates 22 act as reinforcing ribs for the support sealing plate and position the support sealing plate 12 on the heat exchanger shell.

[0023] Diversion holes 15 are provided on the heat exchange tube hole bridges of the diversion support plate 10. The diversion holes 15 are conducive to the shell-side fluid flowing into the U-bend pipe section to participate in heat transfer.

[0024] The support and diversion leakage prevention structure 6 is installed on the U-shaped bend section of the U-tube cross-flow heat exchanger. Its diversion support plate 10 also serves as the support plate for the U-shaped heat exchange tube bundle 5. The U-shaped diversion leakage prevention plate 11 cooperates with the U-shaped bend part of the U-shaped heat exchange tube bundle 5, which not only guides the shell-side fluid into the U-shaped bend section but also prevents the shell-side fluid from leaking along the gap between the heat exchanger shell 3 and the U-shaped tube bundle 5. The shell-side fluid flows in from the shell-side inlet 8 and is evenly distributed along the axial direction of the U-shaped heat exchange tube bundle 5 after flowing in. When it reaches the rear section of the heat exchange tube, it flows into the U-shaped bend section along the lower diversion port 17 and the diversion holes 15 on the diversion support plate. Under the combined action of the U-shaped diversion leakage prevention plate 11 and the support and sealing plate 12, the U-shaped bend section participates in heat exchange. In the U-shaped bend section, the shell-side fluid after participating in heat transfer is collected through the upper diversion port 14 of the diversion support plate and flows out of the heat exchanger from the shell-side outlet 4.

Claims

1. A support, diversion and leakage prevention structure for the U-bend of a U-tube type cross-flow heat exchanger, characterized in that, The support and diversion leak-proof structure (6) mainly includes a diversion support plate (10), a U-shaped diversion leak-proof plate (11), a support sealing plate (12), and a sealing elastic pad (13); the diversion support plate (10) is installed on the heat exchange tube bundle and is in sliding fit with the guide rail on the inner wall of the heat exchanger shell through the diversion support plate guide rail mounting holes (16) at its lower part; the diversion support plate (10) is placed at the front end of the U-shaped bend of the U-shaped heat exchange tube bundle, one end of the U-shaped diversion leak-proof plate (11) is connected to the diversion support plate (10), and the other end is lapped in the U-shaped groove (24) of the support sealing plate through the sealing elastic pad (13); a lower diversion port (17) is provided at the lower part of the diversion support plate (10), and an upper diversion port (14) is provided at the upper part.

2. The support, flow guiding and leakage prevention structure of the U-bend of a U-tube type cross-flow heat exchanger according to claim 1, characterized in that, The U-shaped diversion leak-proof area (20) of the U-shaped diversion leak-proof plate (11) is made by matching with the U-shaped bend of the U-shaped heat exchange tube bundle of the heat exchanger, and there is a gap of 5-6 mm between it and the U-shaped heat exchange tube bundle.

3. The support, diversion and leakage prevention structure of the U-shaped bend of a U-tube type cross-flow heat exchanger according to claim 1, characterized in that, The support sealing plate (12) is provided with a strengthening positioning plate (22), and the other end of the strengthening positioning plate (22) is connected to the heat exchanger shell.

4. The support, flow guiding and leakage prevention structure of the U-shaped bend of a U-tube type cross-flow heat exchanger according to claim 1, characterized in that, Diversion holes (15) are provided on the tube bridges of the heat exchange tube holes on the diversion support plate (10).

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