Coaxial spiral tube heat exchanger and manufacturing method

Abstract

The invention provides a coaxial spiral tube heat exchanger and a manufacturing method, and belongs to the technical field of heat exchangers. The spiral tube heat exchanger solves the problem that an existing spiral tube heat exchanger is large in machining difficulty on the premise that the good heat exchange effect is guaranteed. The coaxial spiral tube heat exchanger comprises a plurality of heat exchange tubes, each heat exchange tube comprises an inner tube, an outer tube and an annular sealing part, each inner tube is provided with a heat exchange section penetrating through the corresponding outer tube, the two ends of each inner tube extend out of the corresponding outer tube to form connecting sections, the inner edge of each sealing part is fixedly connected with the outer wall of the corresponding inner tube, and the outer edge of each sealing part is fixedly connected with a port of the corresponding outer tube. A plurality of turbulent flow assemblies are sequentially arranged on the outer wall of the heat exchange section in the length direction of the inner pipe at intervals, the outer side wall of each turbulent flow assembly abuts against the inner side wall of the outer pipe, and at least two independent turbulent flow openings are sequentially formed between the turbulent flow assemblies and the inner pipe and / or the outer pipe in the circumferential direction of the inner pipe. According to the coaxial spiral tube heat exchanger, the machining and manufacturing difficulty is lowered while the good heat exchange effect is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat exchangers, and relates to a coaxial spiral tube heat exchanger and a manufacturing method thereof. Background Art

[0002] With the continuous improvement of the environmental protection concept and the gradual improvement of the utilization rate of existing energy resources, as a general heat exchange device, a heat exchanger has the advantages of being able to recover and reuse heat, thereby achieving the advantages of improving the energy utilization rate. There are spiral wound tube heat exchangers, shell and tube heat exchangers, plate heat exchangers, etc. in heat exchangers. When the flow rate of the fluid is very small, whether a shell and tube heat exchanger or a plate heat exchanger is used, the overall heat transfer coefficient of the heat exchanger will be small due to the too low fluid velocity, and the heat transfer performance of the heat exchanger cannot be fully exerted. In addition to being able to meet the small flow rate conditions, the spiral wound tube heat exchanger also has the advantages of compact structure, high pressure resistance and large heat transfer coefficient.

[0003] Moreover, for fluids with relatively high viscosities, it is generally necessary to provide flow disturbing elements on the spiral tube to prevent fluid short - circuiting. For existing flow disturbing elements, as disclosed in a Chinese patent application [Authorized Publication Number: CN101566437B], a composite sleeve double - spiral tube - shell heat exchanger is composed of a cylinder body having an inlet, an outlet, and an expansion joint for fluid A, a left inner tube sheet fixed near the left end of the cylinder body, a left outer tube sheet fixed at the left end of the cylinder body, a right inner tube sheet fixed near the right end of the cylinder body, a right outer tube sheet fixed at the right end of the cylinder body, an intermediate support tube sheet fixed in the middle of the cylinder body, a support fixed in the middle of the cylinder body, the left ends of the outer tubes of the heat exchange tube bundle are fixed on the left outer tube sheet, the right ends of the outer tubes of the heat exchange tube bundle are fixed on the right outer tube sheet, an outer tube left - end plug is fixed on the left - end face of the outer tube, an outer tube right - end plug is fixed on the right - end face of the outer tube, liquid - passing windows are opened near the left end and near the right end of the outer tube, the left ends of the middle tubes of the heat exchange tube bundle are fixed on the outer tube left - end plug and the outer tube right - end plug surfaces, the left ends and the right ends of the middle tubes of the heat exchange tube bundle are respectively fixed on the outer tube left - end plug and the outer tube right - end plug surfaces, outer spiral blades are fixed on the outer surfaces of the middle tubes, the left outer tube sheet is connected to a short fixing plate strip, the short fixing plate strip is connected to a long fixing plate strip by bolts, the long fixing plate strip is connected to a short fixing rod by bolts, the right outer tube sheet is connected to a short fixing plate strip, the short fixing plate strip is connected to a long fixing plate strip by bolts, the long fixing plate strip is connected to a short fixing rod by bolts, the short fixing rod is fixed to the left and right end plugs of the hollow inner tubes of the heat exchange tube bundle, the left - end plug and the right - end plug of the hollow inner tube are fixed at the left and right ends of the hollow inner tube, inner spiral blades are fixed on the outer surfaces of the hollow inner tubes, the left outer tube sheet is connected to a left tube - box flange through a gasket and a tensioning bolt, a left tube - box is fixed on the left tube - box flange, a left head is fixed on the left tube - box, a fluid B inlet is fixed on the left tube - box, the right outer tube sheet is connected to a right tube - box flange through a gasket and a tensioning bolt, a right tube - box is fixed on the right tube - box flange, a right head is fixed on the right tube - box, and a fluid outlet is fixed on the right tube - box.

[0004] In the above - mentioned structure, outer spiral blades are fixed on the outer surfaces of the middle tubes, and inner spiral blades are fixed on the outer surfaces of the hollow inner tubes. By using clockwise or counter - clockwise spiral rotation directions that are opposite to each other for the inner and outer spirals, the fluids are always in a cross - flow state when flowing, thereby improving the heat - exchange effect. Moreover, both the outer spiral blades and the inner spiral blades can achieve a good flow - disturbing effect. However, whether it is the outer spiral blades or the inner spiral blades, they are generally a long - strip - shaped object as a whole, and are generally connected to the middle tubes and the hollow inner tubes by welding or integral molding. This results in the need to strictly weld according to the established welding points, or the need to use a specific mold for demolding, making the installation and processing of the inner spiral blades and the outer spiral blades have relatively large difficulties. Therefore, although the above - mentioned structure can achieve a good heat - exchange effect, the processing difficulty is relatively large, which increases the manufacturing cost of the heat exchanger. Summary of the Invention

[0005] The object of the present invention is to address the above problems existing in the prior art and propose a coaxial spiral tube heat exchanger. The technical problem to be solved by the present invention is: how to solve the problem that the existing spiral tube heat exchanger has a large processing difficulty while ensuring better heat exchange effect.

[0006] The object of the present invention can be achieved by the following technical solutions:

[0007] A coaxial spiral tube heat exchanger, comprising a plurality of heat exchange tubes. Each heat exchange tube includes an inner tube, an outer tube and an annular sealing member. The inner tube has a heat exchange section disposed inside the outer tube, and both ends of the inner tube extend out of the outer tube to form connection sections. The inner edge of the sealing member is fixedly connected to the outer wall of the inner tube, and the outer edge of the sealing member is fixedly connected to the port of the outer tube. It is characterized in that a plurality of flow disturbing components are sequentially arranged at intervals along the length direction of the inner tube on the outer wall of the heat exchange section. The outer side wall of each flow disturbing component abuts against the inner side wall of the outer tube. At least two mutually independent flow disturbing openings are sequentially formed between the flow disturbing components and the inner tube and / or the outer tube along the circumferential direction of the inner tube. An annular liquid distributing plate is sleeved on the heat exchange section. A liquid guiding flow channel is formed between the outer edge of the liquid distributing plate and the outer tube. The outer tube has a liquid inlet pipe portion inclined towards the liquid distributing plate along the direction of the inlet of the inner tube, and the outer port of the liquid inlet pipe portion is the liquid inlet of the outer tube.

[0008] A plurality of flow disturbing components are arranged between the inner tube and the outer tube. The flow disturbing components are arranged at intervals along the length direction of the inner tube on the outer wall of the heat exchange section of the inner tube. A plurality of flow disturbing openings are formed between the flow disturbing components and the inner tube and / or the outer tube. When the flow rate of the fluid is small and the viscosity is large, only the flow disturbing openings arranged at intervals along the circumferential direction of the inner tube are needed for flow disturbance to increase the turbulence degree of the fluid and improve the heat transfer coefficient of the fluid. During processing, since there are a plurality of flow disturbing components and they are sequentially arranged at intervals along the length direction of the heat exchange section, the connection of each flow disturbing component is relatively independent. Only the installation positions of the corresponding flow disturbing components need to be found on the inner tube. When one of the flow disturbing components has a position error, it does not affect the installation of the other flow disturbing components, so that the flow disturbing components can be stably welded on the inner tube, reducing the processing difficulty of the heat exchange tube; the fluid to be heated enters between the outer tube and the inner tube from the liquid inlet pipe portion of the outer tube. By sleeving a liquid distributing plate near the liquid inlet of the outer tube and the outer tube is inclined, the fluid directly flows to the liquid distributing plate through the guiding of the liquid inlet pipe portion. Through the guiding of the liquid distributing plate, the fluid flows downward through the liquid guiding flow channel, enabling the fluid with large viscosity to flow downward evenly along the liquid guiding flow channel, avoiding the local non-uniformity of the fluid during the heat exchange process, and combining with a plurality of flow disturbing openings to divide the flow cross-section between the inner tube and the outer tube into a plurality of relatively independent flow channels, preventing the occurrence of laminar flow during the fluid flow and improving the heat transfer efficiency of the heat exchange tube. In summary, the above structure reduces the processing and manufacturing difficulty while ensuring better heat exchange effect.

[0009] In actual use, fluid one enters from the inlet of the inner tube and flows axially along the inner tube. Fluid two enters into the space between the outer side wall of the inner tube and the inner side wall of the outer tube from the liquid inlet pipe part. Fluid two enters in a manner that is tangent to the outer surface of the inner tube and has axial flow and circumferential flow. When fluid two encounters the liquid equalizing plate, its direction will change, and it will enter the liquid guiding flow channel in a manner that has radial flow and circumferential flow. Then, it is evenly distributed into the channels formed by dividing the inner tube lengthwise by the turbulence generating components, and passes through the turbulence generating openings of multiple turbulence generating components, and flows axially along the inner tube for heat exchange.

[0010] In the above coaxial spiral tube heat exchanger, the turbulence generating component is at least three turbulence generating blocks. The turbulence generating blocks are cylindrical. The turbulence generating blocks and the inner tube and the outer tube enclose a turbulence generating opening. The turbulence generating blocks of each group of turbulence generating components are evenly arranged along the circumferential direction of the inner tube.

[0011] The setting of the turbulence generating blocks is convenient for installation on the inner tube. And by setting at least three turbulence generating blocks and evenly arranging them along the circumferential direction of the inner tube, while being able to achieve a turbulence effect on the fluid, it can also reduce the influence on the fluid flow velocity.

[0012] In the above coaxial spiral tube heat exchanger, the turbulence generating blocks are cylindrical, the outer end face of the turbulence generating blocks is arc-shaped, and has the same curvature radius as the inner side wall of the outer tube.

[0013] The shape setting of the turbulence generating blocks can prevent relative displacement between the inner tube and the outer tube from causing mechanical damage to the outer tube.

[0014] In the above coaxial spiral tube heat exchanger, the turbulence generating component is a turbulence generating plate in the shape of an annular plate. The turbulence generating plate is sleeved on the inner tube. A plurality of openings are circumferentially spaced on the inner side wall of the turbulence generating plate. The openings and the outer side wall of the inner tube enclose the above-mentioned turbulence generating opening.

[0015] Compared with the turbulence generating blocks, the turbulence generating plate can increase the contact area with the fluid and enhance the turbulence effect of the fluid. And the integral design of the turbulence generating plate is also convenient for installing the turbulence generating plate on the inner tube, simplifying the processing.

[0016] In the above coaxial spiral tube heat exchanger, the outer side wall of the turbulence generating plate is arc-shaped, and has the same curvature radius as the inner side wall of the outer tube.

[0017] The shape setting of the turbulence generating plate can prevent relative displacement between the inner tube and the outer tube from causing mechanical damage to the outer tube.

[0018] In the above coaxial spiral tube heat exchanger, the outer tube further has a liquid outlet pipe portion that is inclined outward along the outlet of the inner tube. The liquid inlet pipe portion and the liquid outlet pipe portion are respectively located at both ends of the outer tube. The outer port of the liquid outlet pipe portion is the liquid outlet of the outer tube. Flow guiding portions are formed at positions close to the liquid inlet and the liquid outlet of the heat exchange section. The flow guiding portions are in a straight tube shape, and the above-mentioned liquid distribution plate is only sleeved on the flow guiding portion close to the liquid inlet pipe portion.

[0019] Only the flow guiding portion close to the liquid inlet pipe portion is provided with a liquid distribution plate. The liquid distribution plate mainly equalizes the fluid that just enters between the outer tube and the inner tube of the outer tube. The setting of the flow guiding portion avoids the disturbance component being arranged at the liquid inlet and the liquid outlet, which affects the inlet and outlet efficiency of the fluid, and improves the flow velocity of the fluid while ensuring the heat transfer efficiency.

[0020] The liquid outlet pipe portion is also inclined, so that after the fluid two is heated by the heat exchange tube, it can flow out quickly through the liquid outlet pipe portion.

[0021] In the above coaxial spiral tube heat exchanger, the liquid inlet pipe portion is in a straight tube shape, and the included angle A formed by the central axis of the liquid inlet pipe portion and the central axis of the inner tube is less than 45°. The liquid inlet pipe portion is inclined to one side along the circumferential direction of the outer tube, and the inclined angle B is less than 30°.

[0022] By having two-direction inclined angles of the central axis of the liquid inlet pipe portion relative to the central axis of the inner tube, when the fluid enters the inner tube from the liquid inlet pipe portion and impacts the liquid distribution plate, a swirling flow can be formed, which helps the fluid with relatively high viscosity to rotate along the circumferential direction of the liquid distribution plate and then flow down along the liquid guiding channel, thereby improving the uniformity of the fluid passing between the inner tube and the outer tube and realizing uniform heat exchange of the fluid.

[0023] The liquid inlet pipe portion is arranged in a non-orthogonal manner with the outer tube to prevent the fluid two from directly impacting the inner tube after entering, causing erosion of the inner tube, and at the same time increasing the flow cross-sectional area after the fluid two enters; the liquid inlet pipe portion enters in a non-completely axially tangent manner with the outer tube to prevent the fluid two from being too concentrated after entering, and flowing forward with a large flow rate on the entering side, unable to achieve relatively uniform distribution of the fluid two; the liquid inlet pipe portion enters in a non-completely circumferentially tangent manner with the outer tube, also to prevent the fluid two from having no radial flow after entering and unable to achieve relatively uniform distribution of the fluid two.

[0024] A manufacturing method of a coaxial spiral tube heat exchanger, which is based on the above structural content and is characterized by including the following steps:

[0025] A. Splice straight steel pipes that meet the inner tube specification dimensions to the designed length in sequence;

[0026] B. Process the two end faces of several cylindrical flow spoilers into coaxial arc surfaces. The curvature radius of one arc surface is equal to the curvature radius of the outer surface of the inner tube, and the curvature radius of the other arc surface is equal to the curvature radius of the inner surface of the outer tube.

[0027] C. Weld multiple groups of flow spoilers onto the inner tube at equal intervals along the length direction of the inner tube. The flow spoilers on the inner tube in the same cross-section are evenly distributed along the circumferential direction of the inner tube.

[0028] D. Mark at a distance of 50 mm to 80 mm between the flow spoiler closest to the inlet of the inner tube and the corresponding inlet direction of the inner tube, and weld the liquid distribution plate at the marked position of the inlet of the inner tube.

[0029] E. Grind the two ends of multiple straight steel pipes that meet the specification dimensions to form welding bevels, align the corresponding outer tubes, sleeve the aligned outer tubes outside the inner tube, and then weld the adjacent two sections of the outer tubes.

[0030] F. Fit the closures onto both ends of the outer tube, weld the outer edges of the closures onto the ends of the outer tube, and weld the inner edges of the closures onto the inner tube.

[0031] G. Place the welded inner tube and outer tube on the bending die tube, and bend the welded outer tube and inner tube into a spiral coil according to the required pitch, helix direction, and bending radius.

[0032] In the manufacturing method of the above coaxial spiral tube heat exchanger, first splice multiple straight steel pipes to form an inner tube, then weld the flow spoilers and the liquid distribution plate onto the inner tube, then sleeve multiple straight steel pipe-shaped outer tubes outside the inner tube and weld them, weld the closures onto both ends of the inner tube. After the installation is completed, place the entire welded inner tube and outer tube on the bending die tube to support the spiral coil, so as to quickly install the flow deflectors and the liquid distribution plate inside the inner tube, and it is also convenient for the inner tube and the outer tube to maintain coaxial setting during bending, improving the processing efficiency.

[0033] In the manufacturing method of the above coaxial spiral tube heat exchanger, after the step G, measure the horizontal position of the outer tube corresponding to the liquid distribution plate, open a notch at the position where the outer tube is higher than the liquid distribution plate, process one end of the straight pipe-shaped liquid inlet pipe part into an inclined surface, and weld the inclined surface end of the liquid inlet pipe part to the notch of the outer tube and set it obliquely.

[0034] Since the central axis of the liquid inlet pipe part is inclined in two directions compared to the central axis of the inner tube, and the liquid inlet pipe part is located outside the outer tube, the liquid inlet pipe part is likely to affect the positioning during the bending of the bending die tube. Therefore, after the bending forming, weld the liquid inlet pipe part onto the outer tube, which is convenient for processing.

[0035] In the manufacturing method of the above coaxial spiral tube heat exchanger, after the step G, an installation opening is provided at the other end of the outer tube, one end of the straight tube-shaped liquid outlet pipe portion is subjected to bevel processing, and the bevel end of the liquid outlet pipe portion is welded to the installation opening of the outer tube and is inclined.

[0036] An installation opening is directly provided on the outer tube, and the bevel end of the liquid outlet pipe portion is welded to the installation opening of the outer tube, making the installation of the liquid outlet pipe portion more convenient and facilitating processing.

[0037] A manufacturing method of a coaxial spiral tube heat exchanger, which is based on the above structural content and is characterized by including the following steps:

[0038] A. Splicing straight steel pipes that meet the inner tube specification dimensions to the designed length in sequence;

[0039] B. Processing a plurality of plate-shaped flow disturbing plates so that the inner circle diameter is equal to the outer circle diameter of the inner tube and the outer circle diameter is equal to the inner circle diameter of the outer tube, and opening a plurality of openings evenly distributed in the circumferential direction radially outward along the inner circle of the flow disturbing plates;

[0040] C. Welding a plurality of flow disturbing plates to the inner tube at equal intervals along the length direction of the inner tube;

[0041] D. Marking at a position 50 mm to 80 mm away from the corresponding inner tube inlet direction for the flow disturbing block closest to the inner tube inlet, and welding the liquid distribution plate at the marked position of the inner tube inlet;

[0042] E. Grinding welding bevels at both ends of multiple straight steel pipes that meet the specification dimensions, aligning the corresponding outer tubes, sleeving the aligned outer tubes outside the inner tube, and then welding adjacent two straight tubes;

[0043] F. Sleeving the sealing members at both ends of the outer tube, welding the outer edges of the sealing members to the ends of the outer tube, and welding the inner edges of the sealing members to the inner tube;

[0044] G. Placing the welded inner tube and outer tube on the bending die tube, and bending the welded outer tube and inner tube into spiral coil tubes according to the required pitch, helix direction and bending radius.

[0045] In the manufacturing method of the above heat exchange tubes, first splice multiple straight steel pipes to form an inner tube, then weld the flow disturbing plates and the liquid distribution plate to the inner tube, then sleeve multiple straight tube-shaped outer tubes outside the inner tube and weld them, weld the sealing members to both ends of the inner tube, and after the installation is completed, place the entire welded inner tube and outer tube on the bending die tube to support the spiral coil tube, so that the installation of the flow disturbing plates and the liquid distribution plate inside the inner tube can be quickly realized, and it is also convenient for the inner tube and the outer tube to be coaxially arranged during bending, improving the processing efficiency.

[0046] In the manufacturing method of the coaxial spiral tube heat exchanger described above, after the step G, the horizontal position of the outer tube corresponding to the liquid distribution plate is measured. A notch is provided at the position where the outer tube is higher than the liquid distribution plate. One end of the straight liquid inlet pipe portion is processed into an inclined surface. The inclined surface end of the liquid inlet pipe portion is welded to the notch of the outer tube and is inclined.

[0047] Since the central axis of the liquid inlet pipe portion is inclined in two directions compared to the central axis of the inner tube, and the liquid inlet pipe portion is located outside the outer tube, the liquid inlet pipe portion is likely to affect positioning during the bending of the bending die tube. Therefore, after bending and forming, the liquid inlet pipe portion is welded to the outer tube, which is convenient for processing.

[0048] In the manufacturing method of the coaxial spiral tube heat exchanger described above, after the step G, an installation opening is provided at the other end of the outer tube. One end of the straight liquid outlet pipe portion is processed into an inclined surface. The inclined surface end of the liquid outlet pipe portion is welded to the installation opening of the outer tube and is inclined.

[0049] An installation opening is directly provided on the outer tube, and the inclined surface end of the liquid outlet pipe portion is welded to the installation opening of the outer tube, making the installation of the liquid outlet pipe portion more convenient and facilitating processing.

[0050] Compared with the prior art, the coaxial spiral tube heat exchanger has the following advantages:

[0051] 1. During processing, since there are multiple flow disturbance components, which are sequentially and spaced apart along the length direction of the heat exchange section, the connection of each flow disturbance component is relatively independent. Only the installation positions of the corresponding flow disturbance components need to be found on the inner tube. When there is a position error in one flow disturbance component, it does not affect the installation of the other flow disturbance components, enabling the flow disturbance components to be stably welded to the inner tube and reducing the processing difficulty of the heat exchange tube.

[0052] 2. By setting the central axis of the liquid inlet pipe portion to have two-directional inclination angles relative to the central axis of the inner tube, when the fluid enters the inner tube from the liquid inlet pipe portion and impacts the liquid distribution plate, a swirling flow can be formed, which helps the fluid with relatively high viscosity to rotate circumferentially along the liquid distribution plate and then flow down along the liquid guiding flow channel, thereby improving the uniformity of the fluid flowing between the inner tube and the outer tube and achieving uniform heat exchange of the fluid.

[0053] 3. Whether the temperature difference between the fluid one entering the inner tube and the fluid two entering between the inner tube and the outer tube from the liquid inlet pipe portion is large, or the temperature difference of a single fluid stream of fluid one or fluid two is large, this heat exchanger has a good mechanical structure and will not cause structural instability due to temperature difference stress.

[0054] 4. First, turbulator blocks and liquid distribution plates are welded onto the straight inner tube. Then, multiple straight outer tubes are sleeved over the inner tube and welded. After welding, the entire heat exchange tube is bent using a bending die tube, ensuring that the inner tube and the outer tube are coaxially arranged. After bending, the liquid inlet pipe section is welded onto the outer tube according to the previous inclination angle requirement, making its manufacturing and processing more convenient and fast.

[0055] 5. First, turbulator plates and liquid distribution plates are welded onto the straight inner tube. Then, multiple straight outer tubes are sleeved over the inner tube and welded. After welding, the entire heat exchange tube is bent using a bending die tube, ensuring that the inner tube and the outer tube are coaxially arranged. After bending, the liquid inlet pipe section is welded onto the outer tube according to the previous inclination angle requirement, making its manufacturing and processing more convenient and fast. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a partial structural schematic diagram of the first embodiment.

[0057] Figure 2 is a top view of the present invention.

[0058] Figure 3 is a partial schematic diagram of the first embodiment.

[0059] Figure 4 is a partial cross-sectional view of the liquid inlet pipe section in the present invention.

[0060] Figure 5 is a partial side view of the present invention.

[0061] Figure 6 is a partial schematic diagram of the second embodiment.

[0062] Figure 7 is a structural schematic diagram of the turbulator plate in the second embodiment.

[0063] In the figures, 1. Heat exchange tube; 2. Inner tube; 21. Heat exchange section; 21a. Flow guiding section; 21b. Inlet; 21c. Outlet; 22. Connection section; 3. Outer tube; 31. Liquid inlet pipe section; 32. Liquid inlet; 33. Liquid outlet; 34. Liquid outlet pipe section; 4. Sealing member; 5. Turbulator assembly; 51. Turbulator opening; 52. Turbulator block; 53. Turbulator plate; 53a. Opening; 6. Liquid distribution plate; 7. Liquid guiding flow channel. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0064] The following are specific embodiments of the present invention in combination with the drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0065] Embodiment 1

[0066] As Figures 1-5As shown in the figure, the coaxial spiral tube heat exchanger includes a heat exchange tube 1. The heat exchange tube 1 includes an inner tube 2, an outer tube 3, and an annular sealing member 4. The inner tube 2 has a heat exchange section 21 disposed inside the outer tube 3. Both ends of the inner tube 2 extend out of the outer tube 3 and form connection sections 22. The inner edge of the sealing member 4 is fixedly connected to the outer wall of the inner tube 2, and the outer edge of the sealing member 4 is fixedly connected to the port of the outer tube 3.

[0067] Specifically, as Figures 1-5 shown in the figure, a plurality of turbulence components 5 are sequentially arranged at intervals along the length direction of the inner tube 2 on the outer wall of the heat exchange section 21. The outer side wall of each turbulence component 5 abuts against the inner side wall of the outer tube 3. At least two mutually independent turbulence ports 51 are sequentially formed between the turbulence components 5 and the inner tube 2 and / or the outer tube 3 along the circumferential direction of the inner tube 2. An annular liquid distribution plate 6 is sleeved on the heat exchange section 21. A liquid guiding flow channel 7 is formed between the outer edge of the liquid distribution plate 6 and the outer tube 3. The outer tube 3 has a liquid inlet pipe portion 31 inclined towards the liquid distribution plate 6 along the direction of the inlet 21b of the inner tube 2. The outer port of the liquid inlet pipe portion 31 is the liquid inlet 32 of the outer tube 3. The inner tube 2 and the outer tube 3 have the same bending radius, the same rotation axis, and the same helix angle.

[0068] A plurality of turbulence components 5 are arranged between the inner tube 2 and the outer tube 3. The turbulence components 5 are arranged at intervals along the length direction of the inner tube 2 on the outer wall of the heat exchange section 21 of the inner tube 2. A plurality of turbulence ports 51 are formed between the turbulence components 5 and the inner tube 2 and / or the outer tube 3. When the flow rate of the fluid is small and the viscosity is large, only the turbulence through a plurality of turbulence ports 51 arranged at intervals along the circumferential direction of the inner tube 2 is required to increase the turbulence degree of the fluid, so as to improve the heat transfer coefficient of the fluid. During processing, since the connection of each turbulence component 5 is relatively independent, only the installation positions of the corresponding turbulence components 5 need to be found on the inner tube 2. When one of the turbulence components 5 has a position error, it does not affect the installation of the other turbulence components 5, enabling the turbulence components 5 to be stably welded on the inner tube 2 and reducing the processing difficulty of the heat exchange tube 1; The fluid to be heated enters between the outer tube 3 and the inner tube 2 from the liquid inlet pipe portion 31 of the outer tube 3. By sleeving a liquid distribution plate 6 near the liquid inlet of the outer tube 3 and the outer tube 3 is inclined, the fluid directly flows to the liquid distribution plate 6 through the guidance of the liquid inlet pipe portion 31. Through the guidance of the liquid distribution plate 6, the fluid flows downward through the liquid guiding flow channel 7, enabling the fluid with a large viscosity to flow uniformly downward along the liquid guiding flow channel 7, avoiding local non-uniformity of the fluid during the heat exchange process, and combining a plurality of turbulence ports 51 to divide the flow cross-section between the inner tube 2 and the outer tube 3 into a plurality of relatively independent flow channels, preventing laminar flow during the fluid flow and improving the heat transfer efficiency of the heat exchange tube 1. In summary, the above structure reduces the processing and manufacturing difficulty while ensuring a good heat exchange effect.

[0069] During actual use, fluid one enters from the inlet 21b of the inner tube 2 and flows axially along the inner tube 2. Fluid two enters from the liquid inlet pipe portion 31 into the space between the outer wall of the inner tube 2 and the inner wall of the outer tube 3. Fluid two enters in a manner that is tangential to the outer surface of the inner tube 2 and has an axial flow and a circumferential flow. When fluid two encounters the liquid distribution plate 6, its direction will change, and it will enter the liquid guiding flow channel 7 in a manner that has a radial flow and a circumferential flow. Then, it is evenly distributed into the channels formed by dividing the turbulator assembly 5 along the length direction of the inner tube 2, and passes through the turbulence ports 51 of multiple turbulator assemblies 5, and flows axially along the inner tube 2 for heat exchange.

[0070] As Figure 1 and Figure 3 shown, the turbulator assembly 5 is at least three turbulator blocks 52. The turbulator blocks 52 and the inner tube 2 and the outer tube 3 enclose to form the turbulence ports 51. The turbulator blocks 52 of each group of turbulator assemblies 5 are evenly arranged along the circumferential direction of the inner tube 2. Preferably, there are four turbulator blocks 52 evenly arranged along the circumferential direction of the inner tube 2. The turbulator blocks 52 are cylindrical, and the outer end surface of the turbulator block 52 is arc-shaped and has the same radius of curvature as the inner wall of the outer tube 3.

[0071] As Figure 2 , Figure 4 and Figure 5 shown, the outer tube 3 also has a liquid outlet pipe portion 34 that is inclined outward along the direction of the outlet 21c of the inner tube 2. The liquid inlet pipe portion 31 and the liquid outlet pipe portion 34 are respectively located at both ends of the outer tube 3. The outer port of the liquid outlet pipe portion 34 is the liquid outlet 33 of the outer tube 3. Flow guiding portions 21a are formed at both the liquid inlet 32 and the liquid outlet 33 near the heat exchange section 21. The flow guiding portions 21a are straight pipes. Only the flow guiding portion 21a near the liquid inlet pipe portion 31 is sleeved with the above-mentioned liquid distribution plate 6. The liquid inlet pipe portion 31 is a straight pipe, and the included angle A formed by the central axis of the liquid inlet pipe portion 31 and the central axis of the inner tube 2 is less than 45°. The liquid inlet pipe portion 31 is inclined to one side along the circumferential direction of the outer tube 3, and the inclined angle B is less than 30°.

[0072] The liquid inlet pipe portion 31 is arranged in a non-orthogonal manner with the outer tube 3 to prevent fluid two from directly impacting the inner tube 2 after entering, causing erosion corrosion of the inner tube 2, and at the same time increasing the flow cross-sectional area after fluid two enters; the liquid inlet pipe portion 31 enters in a non-completely axially tangential manner with the outer tube 3 to prevent fluid two from being too concentrated after entering, and it will flow forward with a large flow rate on the entering side, and it is impossible to achieve a relatively uniform distribution of fluid two; the liquid inlet pipe portion 31 enters in a non-completely circumferentially tangential manner with the outer tube 3, and it is also to prevent fluid two from having no radial flow after entering, and it is impossible to achieve a relatively uniform distribution of fluid two.

[0073] As Figures 1-5 shown, the manufacturing method of this coaxial spiral tube heat exchanger includes the following steps:

[0074] A. Splice the straight steel pipes that meet the specification dimensions of the inner tube 2 to the designed length in sequence;

[0075] B. Process the two end faces of several cylindrical spoiler blocks 52 into coaxial arc surfaces. The curvature radius of one arc surface is equal to the curvature radius of the outer surface of the inner tube 2, and the curvature radius of the other arc surface is equal to the curvature radius of the inner surface of the outer tube 3;

[0076] C. Weld multiple groups of spoiler blocks 52 onto the inner tube 2 at equal intervals along the length direction of the inner tube 2. The spoiler blocks 52 on the inner tube 2 in the same cross-section are evenly distributed circumferentially along the inner tube 2;

[0077] D. Mark at a distance of 50 mm to 80 mm between the spoiler block 52 closest to the inlet 21b of the inner tube 2 and the corresponding inlet 21b of the inner tube 2, and weld the liquid distribution plate 6 at the marked position of the inlet 21b of the inner tube 2;

[0078] E. Grind the two ends of multiple straight steel pipes that meet the specification dimensions to form welding bevels, align them with the corresponding outer tube 3, sleeve the aligned outer tube 3 outside the inner tube 2, and then weld the adjacent two sections of the outer tube 3;

[0079] F. Fit the closures 4 onto both ends of the outer tube 3, weld the outer edges of the closures 4 to the ends of the outer tube 3, and weld the inner edges of the closures 4 to the inner tube 2;

[0080] G. Place the welded inner tube 2 and outer tube 3 on the bending die tube, and bend the welded outer tube 3 and inner tube 2 into a spiral coiled tube according to the required pitch, helix direction, and bending radius;

[0081] Measure the horizontal position of the outer tube 3 corresponding to the liquid distribution plate 6, open a notch at the position where the outer tube 3 is higher than the liquid distribution plate 6, process one end of the straight pipe-shaped liquid inlet pipe portion 31 into an inclined surface, weld the inclined surface end of the liquid inlet pipe portion 31 to the notch of the outer tube 3 and set it obliquely; open an installation port at the other end of the outer tube 3, process one end of the straight pipe-shaped liquid outlet pipe portion 34 into an inclined surface, weld the inclined surface end of the liquid outlet pipe portion 34 to the installation port of the outer tube 3 and set it obliquely.

[0082] Embodiment 2

[0083] The content of this embodiment is basically the same as that of Embodiment 1, and the difference lies in:

[0084] As Figure 6 and Figure 7 shown, the spoiler assembly 5 is a spoiler plate 53 in the shape of an annular plate. The spoiler plate 53 is sleeved on the inner tube 2. A plurality of openings 53a are spaced circumferentially on the inner side wall of the spoiler plate 53. The openings 53a and the outer side wall of the inner tube 2 enclose the above-mentioned spoiler openings 51. The outer side wall of the spoiler plate 53 is circular arc-shaped and has the same curvature radius as the inner side wall of the outer tube 3.

[0085] The spoiler 53 can increase the contact area with the fluid compared to the spoiler block 52, enhancing the fluid spoiler effect. Moreover, the integral design of the spoiler 53 facilitates the installation of the spoiler 53 on the inner tube 2, simplifying the processing. The shape of the spoiler 53 can prevent relative displacement between the inner tube 2 and the outer tube 3 and mechanical damage to the outer tube 3.

[0086] As Figure 2 and Figures 4-7 shown, the manufacturing method of this coaxial spiral tube heat exchanger includes the following steps:

[0087] A. Splice straight steel pipes that meet the specification dimensions of the inner tube 2 in sequence to the designed length;

[0088] B. Process a number of plate-shaped spoilers 53 so that the inner circle diameter is equal to the outer circle diameter of the inner tube 2 and the outer circle diameter is equal to the inner circle diameter of the outer tube 3. Along the radial direction of the inner circle of the spoiler 53, a plurality of openings 53a evenly distributed in the circumferential direction are opened;

[0089] C. Weld a plurality of spoilers 53 to the inner tube 2 at equal intervals along the length direction of the inner tube 2;

[0090] D. Mark the distance between the spoiler 53 closest to the inlet 21b of the inner tube 2 and the corresponding inlet 21b of the inner tube 2 at 50 mm to 80 mm, and weld the liquid distribution plate 6 at the marked position of the inlet 21b of the inner tube 2;

[0091] E. Grind the two ends of multiple straight steel pipes that meet the specification dimensions to form welding bevels, align the corresponding outer tube 3, sleeve the aligned outer tube 3 outside the inner tube 2, and then weld adjacent two straight pipes;

[0092] F. Fit the closures 4 onto both ends of the outer tube 3, weld the outer edges of the closures 4 to the ends of the outer tube 3, and weld the inner edges of the closures 4 to the inner tube 2;

[0093] G. Place the welded inner tube 2 and outer tube 3 on the bending die tube, and bend the welded outer tube 3 and inner tube 2 into spiral coiled tubes according to the required pitch, helix direction, and bending radius;

[0094] Measure the horizontal position of the outer tube 3 corresponding to the liquid distribution plate 6, open a notch at the position where the outer tube 3 is higher than the liquid distribution plate 6, chamfer one end of the straight pipe-shaped liquid inlet pipe portion 31, weld the chamfered end of the liquid inlet pipe portion 31 to the notch of the outer tube 3 and set it obliquely; open an installation opening at the other end of the outer tube 3, chamfer one end of the straight pipe-shaped liquid outlet pipe portion 34, weld the chamfered end of the liquid outlet pipe portion 34 to the installation opening of the outer tube 3 and set it obliquely.

[0095] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar means for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A coaxial spiral tube heat exchanger, comprising a heat exchange tube (1), the heat exchange tube (1) comprising an inner tube (2), an outer tube (3) and an annular closing member (4), the inner tube (2) having a heat exchange section (21) penetrating the outer tube (3), both ends of the inner tube (2) extending out of the outer tube (3) to form a connecting section (22), the inner edge of the closing member (4) being fixedly connected to the outer wall of the inner tube (2), and the outer edge of the closing member (4) being fixedly connected to the end of the outer tube (3), characterized in that: The outer wall of the heat exchange section (21) is provided with a plurality of spoiler components (5) arranged in sequence and at intervals along the length direction of the inner tube (2); the outer wall of each spoiler component (5) abuts against the inner wall of the outer tube (3); at least two mutually independent spoiler ports (51) are formed in sequence between the spoiler component (5) and the inner tube (2) and / or the outer tube (3) along the circumference of the inner tube (2); an annular liquid equalizing plate (6) is sleeved on the heat exchange section (21); a liquid guide channel (7) is formed between the outer edge of the liquid equalizing plate (6) and the outer tube (3); the outer tube (3) has a liquid inlet pipe portion (31) arranged obliquely toward the liquid equalizing plate (6) along the direction of the inlet (21b) of the inner tube (2); and the outer end of the liquid inlet pipe portion (31) is the liquid inlet port (32) of the outer tube (3).

2. The coaxial spiral tube heat exchanger according to claim 1, characterized in that: The spoiler assembly (5) comprises at least three spoiler blocks (52), wherein the spoiler blocks (52) and the inner tube (2) and the outer tube (3) together form a spoiler opening (51), and the spoiler blocks (52) of each group of spoiler assemblies (5) are evenly arranged along the circumference of the inner tube (2).

3. The coaxial spiral tube heat exchanger according to claim 2, characterized in that: The spoiler block (52) is cylindrical, and the outer end surface of the spoiler block (52) is arc-shaped and has the same curvature radius as the inner side wall of the outer tube (3).

4. The coaxial spiral tube heat exchanger according to claim 1, characterized in that: The spoiler assembly (5) is a spoiler (53) in the form of an annular plate. The spoiler (53) is sleeved on the inner tube (2). The inner side wall of the spoiler (53) is provided with a plurality of openings (53a) spaced apart along the circumferential direction. The openings (53a) and the outer side wall of the inner tube (2) are combined to form the above-mentioned spoiler opening (51).

5. The coaxial spiral tube heat exchanger according to claim 4, characterized in that: The outer side wall of the spoiler (53) is in an arc shape and has the same curvature radius as the inner side wall of the outer tube (3).

6. The coaxial spiral tube heat exchanger according to any one of claims 1 to 5, characterized in that: The outer tube (3) further comprises a liquid outlet pipe portion (34) arranged outwardly in a direction of the outlet (21c) of the inner tube (2); the liquid inlet pipe portion (31) and the liquid outlet pipe portion (34) are respectively located at two ends of the outer tube (3); the outer end of the liquid outlet pipe portion (34) is the liquid outlet (33) of the outer tube (3); the heat exchange section (21) is provided with a guide portion (21a) near the liquid inlet (32) and the liquid outlet (33); the guide portion (21a) is in the shape of a straight tube; and the above-mentioned liquid balancing plate (6) is only provided on the guide portion (21a) near the liquid inlet pipe portion (31).

7. The coaxial spiral tube heat exchanger according to any one of claims 1 to 5, characterized in that: The liquid inlet pipe portion (31) is in the shape of a straight pipe, and the angle A formed by the central axis of the liquid inlet pipe portion (31) and the central axis of the inner pipe (2) is less than 45°. The liquid inlet pipe portion (31) is inclined to one side along the circumference of the outer pipe (3), and the inclination angle B is less than 30°.

8. A method for manufacturing a coaxial spiral tube heat exchanger, the method comprising the heat exchange tube (1) according to any one of claims 1 to 3 and claim 6 and claim 7, characterized in that: The following steps are involved: A. Splice straight steel pipes that meet the specifications of the inner pipe (2) in sequence to the designed length; B. machining two end surfaces of a plurality of cylindrical spoilers (52) to form coaxial arc surfaces, wherein the curvature radius of one arc surface is equal to the curvature radius of the outer surface of the inner tube (2), and the curvature radius of the arc surface at the other end is equal to the curvature radius of the inner surface of the outer tube (3); C. welding a plurality of groups of spoiler blocks (52) to the inner tube (2) at equal intervals along the length direction of the inner tube (2), so that the spoiler blocks (52) of the inner tube (2) on the same cross section are evenly distributed along the circumference of the inner tube (2); D. Mark the spoiler (52) closest to the inlet (21b) of the inner tube (2) at a distance of 50 mm to 80 mm in the direction of the corresponding inlet (21b) of the inner tube (2), and weld the liquid balancing plate (6) to the marked position of the inlet (21b) of the inner tube (2); E. Grinding welding grooves at both ends of multiple sections of straight steel pipes that meet the specifications, aligning the corresponding outer pipes (3), and sleeve the aligned outer pipes (3) outside the inner pipe (2), and then welding the two adjacent sections of the outer pipe (3); F. The closing piece (4) is inserted into both ends of the outer tube (3), the outer edge of the closing piece (4) is welded to the end of the outer tube (3), and the inner edge of the closing piece (4) is welded to the inner tube (2); G. Place the welded inner tube (2) and outer tube (3) on the bending die tube, and bend the welded outer tube (3) and inner tube (2) into a spiral coil according to the required pitch, rotation direction and bending radius.

9. The method for manufacturing a coaxial spiral tube heat exchanger according to claim 8, characterized in that: After step F, the horizontal position of the outer tube (3) corresponding to the liquid balancing plate (6) is measured, a notch is provided at a position of the outer tube (3) above the liquid balancing plate (6), one end of the straight tube-shaped liquid inlet tube portion (31) is beveled, and the beveled end of the liquid inlet tube portion (31) is welded to the notch of the outer tube (3) and arranged in an inclined manner.

10. A method for manufacturing a coaxial spiral tube heat exchanger, the method comprising the heat exchange tube (1) according to claim 1 and any one of claims 4 to 7, characterized in that: The following steps are involved: A. Splice straight steel pipes that meet the specifications of the inner pipe (2) in sequence to the designed length; B. processing a plurality of plate-shaped spoilers (53) so that their inner diameter is equal to the outer diameter of the inner tube (2) and their outer diameter is equal to the inner diameter of the outer tube (3), and a plurality of openings (53a) evenly distributed along the circumferential direction are formed radially outwardly on the inner circle of the spoiler (53); C. Welding a plurality of spoilers (53) onto the inner tube (2) at equal intervals along the length direction of the inner tube (2); D. Mark the spoiler (53) closest to the inlet (21b) of the inner tube (2) at a distance of 50 mm to 80 mm in the direction of the corresponding inlet (21b) of the inner tube (2), and weld the liquid balancing plate (6) to the marked position of the inlet (21b) of the inner tube (2); E. Grind welding grooves at both ends of multiple straight steel pipes that meet the specifications, align the corresponding outer pipes (3), and put the aligned outer pipes (3) on the outer side of the inner pipe (2), and then weld the two adjacent straight pipes; F. The closing piece (4) is inserted into both ends of the outer tube (3), the outer edge of the closing piece (4) is welded to the end of the outer tube (3), and the inner edge of the closing piece (4) is welded to the inner tube (2); G. Place the welded inner tube (2) and outer tube (3) on the bending die tube, and bend the welded outer tube (3) and inner tube (2) into a spiral coil according to the required pitch, rotation direction and bending radius.

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