Double-pipe heat exchanger with bidirectional spiral flow channel
By using a spiral fin structure to form a spiral flow channel in the shell-and-tube heat exchanger, the medium can exchange heat in a countercurrent manner, which solves the problems of small heat transfer area and low efficiency of existing shell-and-tube heat exchangers, and realizes a high-efficiency and simple heat exchanger design.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ACRE COKING & REFRACTORY ENG CONSULTING CORP DALIAN MCC
- Filing Date
- 2025-05-30
- Publication Date
- 2026-05-08
AI Technical Summary
Existing shell-and-tube heat exchangers have small heat transfer area per unit volume, are difficult to manufacture, and have low heat transfer efficiency. In particular, single-shell and multi-shell heat exchangers have complex structures and are difficult to manufacture.
The structure employs a coaxial inner tube and multiple sleeves with spiral fins to form multiple spiral flow channels, allowing heat exchange medium one and medium two to exchange heat in countercurrent through the corresponding spiral flow channels, thereby increasing the heat exchange area and improving efficiency.
The spiral flow channel structure significantly increases the heat exchange area and efficiency, achieving a heat exchanger design that is simple in structure, has good sealing performance, and is easy to manufacture.
Smart Images
Figure CN224215887U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a shell-and-tube heat exchanger, and more particularly to a shell-and-tube heat exchanger with a bidirectional spiral flow channel. Background Technology
[0002] A shell-and-tube heat exchanger is a common type of indirect heat exchange device, consisting of concentric or eccentrically nested tubes. In a conventional shell-and-tube heat exchanger, hot and cold fluids flow separately in the inner and outer tubes, exchanging heat through the tube walls. Its basic structure includes: an inner tube (serving as the flow path for high-temperature fluids such as steam or hot water), an outer tube (the outer sleeve, wrapped around the inner tube, serving as the flow path for low-temperature fluids such as cold water or air), and connecting components such as U-bends and flanges to extend the flow path or connect multiple sets of shells in series. Typically, shell-and-tube heat exchangers mostly employ counter-flow (two fluids flowing in opposite directions) to improve heat transfer efficiency. The advantages of shell-and-tube heat exchangers are their simple structure, ease of disassembly and cleaning, ability to withstand high pressures, suitability for high temperature difference conditions, and high heat transfer efficiency (especially in counter-flow configurations); the disadvantage is their small heat transfer area per unit volume.
[0003] The petrochemical standard SH-T 3119-2000, "Design Specification for Steel Shell-and-Tube Heat Exchangers in Petrochemical Industry," lists the structures of single-shell and multi-shell heat exchangers. Single-shell heat exchangers employ a bend-back structure, which is relatively difficult to manufacture and results in a smaller heat exchange area. Multi-shell heat exchangers use U-shaped connecting tubes and tube sheets for connection, which is also difficult to manufacture and results in low heat exchange efficiency. Summary of the Invention
[0004] This utility model provides a shell-and-tube heat exchanger with a bidirectional spiral flow channel. The shell-and-tube heat exchanger adopts a structure in which an inner tube is arranged coaxially and spiral fins are arranged between multiple tubes. Multiple spiral flow channels are formed in the tube bundle section of the heat exchanger. Heat exchange medium one and heat exchange medium two exchange heat in countercurrent through the corresponding spiral flow channels. It has a large heat exchange area, high heat exchange efficiency, simple structure and convenient manufacturing.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A shell-and-tube heat exchanger with bidirectional helical flow channels includes a shell-and-tube heat exchanger consisting of a tube box one, a tube box two, and a tube bundle section. The tube bundle section contains an inner tube at a center and several outer tubes coaxially arranged with the inner tube. Helical fins are provided between the inner tube and adjacent outer tubes, between each outer tube, and between the outermost outer tube and the outer wall of the tube bundle section, forming multiple helical flow channels within the tube bundle section. The inner tube extends into tube box one and tube box two. A partition one is provided in the middle of tube box one, dividing tube box one into a medium one inlet area and a medium two outlet area. Counting outwards from the center of the shell-and-tube heat exchanger, the medium one inlet... The odd-numbered spiral flow channels in the medium 2 outlet area are sealed at the end by inlet plug plate 1, and the even-numbered spiral flow channels in the medium 2 outlet area are sealed at the end by outlet plug plate 1. The medium 1 inlet area has a medium 1 inlet, and the medium 2 outlet area has a medium 2 outlet. A baffle plate 2 is provided in the middle of the tube box 2, which divides the tube box 2 into a medium 2 inlet area and a medium 1 outlet area. Counting outward from the center of the shell-and-tube heat exchanger, the even-numbered spiral flow channels in the medium 2 inlet area are sealed at the end by inlet plug plate 2, and the odd-numbered spiral flow channels in the medium 1 outlet area are sealed at the end by outlet plug plate 2. The medium 2 inlet area has a medium 2 inlet, and the medium 1 outlet area has a medium 1 outlet.
[0007] The shell-and-tube heat exchanger is a horizontal shell-and-tube heat exchanger. The outer walls of tube box one, tube box two, and tube bundle section are an integral structure, which together form the shell-and-tube heat exchanger body. The inner tube is arranged along the axial length of the body. The medium one inlet is located at the top of tube box one, and the medium two outlet is located at the bottom of tube box one. The medium two inlet is located at the top of tube box two, and the medium one outlet is located at the bottom of tube box two. Supports are provided on both sides of the bottom of the tube bundle section.
[0008] The outer end of the first pipe box is provided with two semi-circular end blocking plates, which are welded to the inner pipe and the inner wall of the first pipe box along the circumference. The outer side of the two end blocking plates is provided with a circular cover plate, which is welded to the end blocking plates and the inner pipe to seal the corresponding ends of the cylinder and the inner pipe. The outer end of the second pipe box is provided with two semi-circular end blocking plates, which are welded to the inner pipe and the inner wall of the second pipe box along the circumference. The outer side of the two end blocking plates is provided with a circular cover plate, which is welded to the end blocking plates and the inner pipe to seal the corresponding ends of the cylinder and the inner pipe.
[0009] Compared with the prior art, the beneficial effects of this utility model are:
[0010] 1) The structure of setting spiral fins between the inner tube and multiple sleeves on the same axis is adopted, forming multiple spiral flow channels in the tube bundle section of the heat exchanger. Heat exchange medium one and heat exchange medium two exchange heat in countercurrent through the corresponding spiral flow channels, resulting in a large heat exchange area and high heat exchange efficiency.
[0011] 2) The small-radius spiral flow channel is used to make the medium flow in a circular motion, which washes the inner and outer walls of the spiral flow channel (including the inner wall of the cylinder and the outer wall of the inner tube) to achieve a self-cleaning effect.
[0012] 3) The spiral fins not only increase the heat exchange area as fins and guide the medium to flow along the spiral channel, but also serve as supports between the tubes, thus having a self-supporting structure; compared with conventional tube heat exchangers, the heat exchange tubes can be designed to be longer, increasing the heat exchange area.
[0013] 4) The shell-and-tube heat exchanger adopts a welded structure, which has good sealing performance; it does not require a tube sheet, making it easy to manufacture and install. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of the shell-and-tube heat exchanger with a bidirectional spiral flow channel described in this utility model.
[0015] Figure 2 yes Figure 1 View A in the diagram.
[0016] Figure 3 yes Figure 1 BB view in the middle.
[0017] Figure 4 yes Figure 1 The CC view in the middle.
[0018] Figure 5 This is a schematic diagram showing the connection relationship between the spiral fins and the sleeve described in this utility model.
[0019] Figure 6 This is a schematic diagram of the structure of the end blocking plate one (end blocking plate two) of this utility model.
[0020] In the diagram: 1. Pipe box 1-1. Medium 1 inlet 1-2. Medium 2 outlet 1-3. End plug 1-4. Cover plate 1-5. Baffle 1 2. Pipe bundle section 2-1. Inner pipe 2-2. Sleeve 2-3. Spiral fins 2-4. Inlet plug 1 2-5. Outlet plug 1 2-6. Inlet plug 2-7. Outlet plug 2 3. Pipe box 2 3-1. Medium 2 inlet 3-2. Medium 1 outlet 3-3. End plug 2 3-4. Cover plate 2 3-5. Baffle 2 4. Support Detailed Implementation
[0021] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings:
[0022] like Figure 1 , Figure 3 , Figure 4 , Figure 5As shown, the present invention discloses a shell-and-tube heat exchanger with a bidirectional spiral flow channel, comprising a tube box 1, a tube box 2, and a tube bundle section 2. The tube bundle section 2 includes an inner tube 2-1 located at the center and several sleeves 2-2 coaxially arranged with the inner tube 2-1. Spiral fins 2-3 are respectively provided between the inner tube 2-1 and adjacent sleeves 2-2, between each sleeve 2-2, and between the outermost sleeve 2-2 and the outer wall of the tube bundle section 2, forming multiple spiral flow channels within the tube bundle section 2. The inner tube 2-1 extends into the tube box 1 and the tube box 2. A partition 1-5 is provided in the middle of the tube box 1, dividing the tube box 1 into a medium inlet area and a medium outlet area. Counting outwards from the center, the odd-numbered spiral flow channels in the medium-1 inlet area are sealed by inlet plug 2-4, and the even-numbered spiral flow channels in the medium-2 outlet area are sealed by outlet plug 2-5. The medium-1 inlet area is provided with medium-1 inlet 1-1, and the medium-2 outlet area is provided with medium-2 outlet 1-2. A partition 3-5 is provided in the middle of tube box 2, dividing tube box 2 into medium-2 inlet area and medium-1 outlet area. Counting outwards from the center of the shell-and-tube heat exchanger, the even-numbered spiral flow channels in the medium-2 inlet area are sealed by inlet plug 2-6, and the odd-numbered spiral flow channels in the medium-1 outlet area are sealed by outlet plug 2-7. The medium-2 inlet area is provided with medium-2 inlet 3-1, and the medium-1 outlet area is provided with medium-1 outlet 3-2.
[0023] like Figure 1 As shown, the shell-and-tube heat exchanger is a horizontal shell-and-tube heat exchanger. The outer walls of tube box 1, tube box 2, and tube bundle section 2 are an integral structure, which together form the shell-and-tube heat exchanger body. The inner tube 2-1 is arranged along the axial direction of the body. Medium inlet 1-1 is located at the top of tube box 1, and medium outlet 1-2 is located at the bottom of tube box 1. Medium inlet 3-1 is located at the top of tube box 2, and medium outlet 3-2 is located at the bottom of tube box 2. Supports 5 are provided on both sides of the bottom of tube bundle section 2.
[0024] like Figure 1 , Figure 2 , Figure 6 As shown, the outer end of the pipe box 1 is provided with two semi-circular end blocking plates 1-3, which are welded to the inner pipe 2-1 and the inner wall of the pipe box 1 along the circumference. A circular cover plate 1-4 is provided on the outer side of the two end blocking plates 1-3, which is welded to the end blocking plates 1-3 and the inner pipe 2-1 to seal the corresponding ends of the cylinder and the inner pipe 2-1. The outer end of the pipe box 3 is provided with two semi-circular end blocking plates 3-3, which are welded to the inner pipe 2-1 and the inner wall of the pipe box 3 along the circumference. A circular cover plate 3-4 is provided on the outer side of the two end blocking plates 3-3, which is welded to the end blocking plates 3-3 and the inner pipe 2-1 to seal the corresponding ends of the cylinder and the inner pipe 2-1.
[0025] The present invention describes the working method of a shell-and-tube heat exchanger with bidirectional spiral flow channels. Heat exchange medium one enters the medium one inlet area at the upper part of tube box one 1 from medium one inlet 1-1, flows through multiple spaced spiral flow channels through tube bundle section 2, and then enters the medium one outlet area at the lower part of tube box two 3, and then flows out from medium one outlet 3-2. Heat exchange medium two enters the medium two inlet area at the upper part of tube box two 3 from medium two inlet 3-1, flows through multiple spaced spiral flow channels through tube bundle section 2, and then enters the medium two outlet area at the lower part of tube box one 1, and then flows out from medium two outlet 1-2. Heat exchange medium one and heat exchange medium two exchange heat in opposite directions within the multiple spaced spiral flow channels.
[0026] The present invention discloses a shell-and-tube heat exchanger with a bidirectional spiral flow channel, comprising a tube box 1, a tube bundle section 2, and a tube box 3. The tube bundle section 2 is provided with an inner tube 2-1, a sleeve 2-1, and spiral fins 2-3. The tube box 1 is provided with a medium inlet 1-1, a medium outlet 1-2, a baffle 1-5, an end plug 1-3, and a cover 1-4. The tube box 3 is provided with a medium inlet 3-1, a medium outlet 3-2, a baffle 2 3-5, an end plug 2 3-3, and a cover 2 3-4. The shell-and-tube heat exchanger is preferably of a horizontal structure, with a support 4 at the bottom of the tube bundle section 2.
[0027] The inner tube 2-1 is preferably a seamless steel pipe. Both ends of the inner tube 2-1 are sealed by welding with cover plate 1-4 and cover plate 3-4. Multiple sleeves 2-2 are coaxially arranged around the inner tube 2-1. Spiral fins 2-3 are welded between the inner tube 2-1 and the innermost sleeve 2-2, between two adjacent sleeves 2-1, and between the outermost sleeve 2-2 and the outer wall (i.e., the cylinder) of the tube bundle section 2. The axial length of the spiral fins 2-3 is consistent with the length of the sleeves 2-2.
[0028] In the shell-and-tube heat exchanger of this utility model, the spiral fins 2-3 serve as conventional fins to increase the heat exchange area and guide the medium to flow along the spiral flow channel. They also serve as supports between the inner tube 2-1, the shell 2-2, and the cylinder that form each spiral flow channel.
[0029] In the shell-and-tube heat exchanger of this invention, heat exchange medium one enters from the upper space of tube box one 1 into several spaced spiral channels, such as odd-numbered spiral channels (counted from the center outwards), and the flow direction of heat exchange medium one in the odd-numbered spiral channels is forward; while heat exchange medium two enters from the upper space of tube box two 3 into several spaced spiral channels that intersect with heat exchange medium one, such as even-numbered spiral channels (counted from the center outwards), and the flow direction of heat exchange medium two in the even-numbered spiral channels is reversed; that is, it is equivalent to heat exchange medium one and heat exchange medium two flowing and exchanging heat in several spaced bidirectional spiral channels, which greatly increases the heat exchange area.
[0030] A baffle plate 1-5 is installed in the middle of tube box 1 to separate heat exchange medium 1 (inflow end) from heat exchange medium 2 (outflow end); similarly, a baffle plate 3-5 is installed in the middle of tube box 3 to separate heat exchange medium 2 (inflow end) from heat exchange medium 1 (outflow end). Baffle plates 1-5 and 3-5 are welded to the inner tube 2-1, the cylinder, the corresponding blocking plates (including inlet blocking plate 2-4, outlet blocking plate 2-5, inlet blocking plate 2-6, and outlet blocking plate 2-7) and the corresponding end blocking plates (including end blocking plate 1-3 and end blocking plate 2-3-3).
[0031] In the shell-and-tube heat exchanger of this utility model, the shell 2-1, as the outer shell of the heat exchanger, adopts an integral structure. It can be regarded as the outer wall of the tube bundle section 2 extending to both ends to serve as the outer wall of tube box 1 and tube box 2 3. The inner tube 2-1 is also an integral steel pipe. It can be regarded as the inner tube 2-1 of the tube bundle section 2 extending to both ends into tube box 1 and tube box 2 3. The inner tube section located in tube box 1 and tube box 2 3 does not have spiral fins 2-3.
[0032] The spiral flow channel connecting the inlet 1-1 and outlet 3-2 of medium one serves as the channel for heat exchange medium one, which flows along the spiral fins 2-3 within the corresponding spiral flow channel. Similarly, the spiral flow channel connecting the inlet 3-1 and outlet 1-2 of medium two serves as the channel for heat exchange medium two, which flows along the spiral fins 2-3 within the corresponding spiral flow channel. In other words, heat exchange medium one and heat exchange medium two undergo indirect counter-current heat exchange separated by the spiral fins 2-3, resulting in a large heat exchange area.
[0033] The material of the shell-and-tube heat exchanger described in this utility model is determined based on the corrosiveness of heat exchange medium one and heat exchange medium two.
[0034] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A shell-and-tube heat exchanger with a bidirectional helical flow channel, comprising a first tube box, a second tube box, and a tube bundle section; characterized in that, The tube bundle within the tube bundle section includes an inner tube at the center and several sleeves coaxially arranged with the inner tube. Spiral fins are provided between the inner tube and adjacent sleeves, between each sleeve, and between the outermost sleeve and the outer wall of the tube bundle section, forming multiple spiral flow channels within the tube bundle section. The inner tube extends into tube box one and tube box two. A partition plate one is provided in the middle of tube box one, dividing tube box one into a medium one inlet area and a medium two outlet area. Counting outwards from the center of the tube heat exchanger, the odd-numbered spiral flow channel ends of the medium one inlet area are sealed by an inlet plug plate one. The even-numbered spiral flow channel ends in the outlet area of medium two are sealed by outlet plug plate one. The inlet area of medium one is provided with medium one inlet, and the outlet area of medium two is provided with medium two outlet. A baffle plate two is provided in the middle of tube box two, dividing tube box two into medium two inlet area and medium one outlet area. Counting outward from the center of the shell and tube heat exchanger, the even-numbered spiral flow channel ends in the inlet area of medium two are sealed by inlet plug plate two, and the odd-numbered spiral flow channel ends in the outlet area of medium one are sealed by outlet plug plate two. The inlet area of medium two is provided with medium two inlet, and the outlet area of medium one is provided with medium one outlet.
2. A shell-and-tube heat exchanger with a bidirectional helical flow channel according to claim 1, characterized in that, The shell-and-tube heat exchanger is a horizontal shell-and-tube heat exchanger. The outer walls of tube box one, tube box two, and tube bundle section are an integral structure, which together form the shell-and-tube heat exchanger body. The inner tube is arranged along the axial length of the body. The medium one inlet is located at the top of tube box one, and the medium two outlet is located at the bottom of tube box one. The medium two inlet is located at the top of tube box two, and the medium one outlet is located at the bottom of tube box two. Supports are provided on both sides of the bottom of the tube bundle section.
3. A shell-and-tube heat exchanger with a bidirectional helical flow channel according to claim 1, characterized in that, The outer end of the first pipe box is provided with two semi-circular end blocking plates, which are welded to the inner pipe and the inner wall of the first pipe box along the circumference. The outer side of the two end blocking plates is provided with a circular cover plate, which is welded to the end blocking plates and the inner pipe to seal the corresponding ends of the cylinder and the inner pipe. The outer end of the second pipe box is provided with two semi-circular end blocking plates, which are welded to the inner pipe and the inner wall of the second pipe box along the circumference. The outer side of the two end blocking plates is provided with a circular cover plate, which is welded to the end blocking plates and the inner pipe to seal the corresponding ends of the cylinder and the inner pipe.