Shell and tube evaporator, manufacturing process of shell and tube evaporator and snow melting machine

Abstract

The invention relates to a shell and tube evaporator, a manufacturing process of the shell and tube evaporator and a snow melting machine. The process comprises the following specific steps that S1, a refrigerating coil is manufactured; s2, the refrigerating coil is placed in a shell, and the outer side of the refrigerating coil is attached to the inner wall of the shell; meanwhile, an inner-layer composite heat preservation mechanism is placed in the refrigeration coil pipe, and the outer side of the inner-layer composite heat preservation mechanism is attached to the inner side of the refrigeration coil pipe; and S3, a cavity in the inner-layer composite heat preservation mechanism is filled with a foaming agent in a low-pressure mode and then in a gradient pressurization mode. The method has the beneficial effects that the process is simple, the design is reasonable, the heat exchange uniformity is ensured through dynamic winding forming, a gradient composite structure and an intelligent foaming process, the problems of non-uniform tube shell gaps, large contact thermal resistance and foaming agent permeation of a traditional evaporator are solved, and the heat exchange efficiency is improved and long-term stable operation is realized.

Description

Technical Field

[0001] This invention relates to the field of refrigeration equipment technology, specifically to a shell-and-tube evaporator, its manufacturing process, and a snow melting machine. Background Technology

[0002] A slush machine is a commercial beverage processing machine primarily used to quickly transform fruit juice, water, and other ingredients into frozen drinks such as slushies, smoothies, and milkshakes. It is widely used in beverage shops, milk tea shops, cafes, and other food and beverage establishments.

[0003] The core function and working principle of a snow melting machine is as follows: the snow melting machine freezes and stirs liquid raw materials into a smooth slush or shaved ice drink through a built-in refrigeration system (such as an imported compressor) and a stirring device.

[0004] The evaporator used in the snow melting machine is a shell and tube evaporator. The outer shell is cylindrical, and the outer surface of the cylinder is the heat exchange surface that comes into contact with the beverage. The inner surface is in close contact with the refrigeration coil. The inner center side of the coil needs to be insulated to ensure that the cold energy of the coil can be transferred outward in one direction.

[0005] Traditional shell-and-tube evaporators employ a static assembly process, which has the following technical drawbacks: (1) Uneven fitting of tube and shell: Manual assembly causes fluctuations in the gap between the refrigeration coil and the shell (0.2-3mm), and the difference in frost thickness exceeds 40%, which affects the uniformity of heat exchange; (2) Excessive contact thermal resistance: The contact area between the circular copper tube and the shell is only 32%-45% of the theoretical value, and the contact thermal resistance reaches 0.08-0.15m. 2 • K / W, low heat exchange efficiency; (3) Severe foaming agent penetration: In traditional foaming processes, the foaming agent penetrates into the gaps between pipes (permeability > 65%), forming a 0.5-1.2 mm insulation layer, resulting in a loss of 18%-25% of the effective heat exchange area.

[0006] To address the aforementioned technical problems, common solutions include optimizing the copper tube arrangement or adjusting foaming parameters. However, neither of these solutions systematically solves the problems. Therefore, a solution that balances structural innovation and process improvement is urgently needed. Summary of the Invention

[0007] This invention addresses the technical problems existing in the prior art by providing a shell-and-tube evaporator, its manufacturing process, and a snow melting machine.

[0008] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A manufacturing process for a shell-and-tube evaporator includes the following specific steps: S1: Manufacturing refrigeration coils; S2: Place the refrigeration coil into the outer casing, so that its outer side is in contact with the inner wall of the outer casing; at the same time, place the inner composite insulation mechanism into the refrigeration coil, so that its outer side is in contact with the inner side of the refrigeration coil. S3: The foaming agent is first filled into the cavity of the inner composite insulation mechanism under low pressure and then under gradient pressure.

[0009] The beneficial effects of this invention are as follows: During the evaporator manufacturing process, S1: a refrigeration coil is manufactured; S2: the refrigeration coil is placed inside the outer shell, with its outer side fitting against the inner wall of the outer shell; simultaneously, an inner composite insulation mechanism is placed inside the refrigeration coil, with its outer side fitting against the inner side of the refrigeration coil; S3: a foaming agent is filled into the cavity of the inner composite insulation mechanism under low pressure followed by gradient pressure. The process is simple and effectively increases the contact area and contact degree between the refrigeration coil and the outer shell, ensuring the uniformity of heat exchange.

[0010] The present invention has a simple process and a reasonable design. Through dynamic winding molding, gradient composite structure and intelligent foaming process, it ensures the uniformity of heat exchange and solves the problems of uneven tube-shell gap, large contact thermal resistance and foaming agent penetration in traditional evaporators, thereby achieving improved heat exchange efficiency and long-term stable operation.

[0011] Based on the above technical solution, the present invention can be further improved as follows.

[0012] Furthermore, step S1 includes the following specific steps: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil, causing the refrigeration coil to undergo 0.8%-1.2% plastic deformation.

[0013] The advantages of adopting the above-mentioned further solution are that the process is simple and the design is reasonable. It can realize the production of refrigeration coils and make the refrigeration coils fit into the inner surface of the outer shell, which greatly increases the contact area between the refrigeration coils and the outer shell, thereby ensuring the uniformity of heat exchange.

[0014] Furthermore, the cross-section of each coil of the refrigeration tube is elliptical, and the ratio of the major axis to the minor axis of the elliptical cross-section is (0.5-2):0.6.

[0015] The advantages of adopting the above-mentioned further scheme are that the process is simple, the cross-section of each coil of refrigeration tube is more reasonable in an elliptical shape, which greatly increases the contact area between the refrigeration coil and the outer shell, and ensures the uniformity of heat exchange.

[0016] Furthermore, before the spiral winding device winds the refrigeration tube, it also includes S0: performing a three-dimensional heat flow simulation to confirm the winding angle of each turn of the refrigeration tube and the winding pitch between two adjacent turns of the refrigeration tube.

[0017] The advantages of adopting the above-mentioned further scheme are that the method is simple and the design is reasonable. It uses a three-dimensional simulation model to simulate the specific situation of heat flow conduction under different winding angles and winding pitches, so as to determine the optimal winding angle and winding pitch of the refrigeration tube and ensure the uniformity of heat exchange.

[0018] Furthermore, the winding angle of each turn of the refrigeration tube is in the range of 87°-88°, and the winding pitch between two adjacent turns of the refrigeration tube is in the range of 8-12mm.

[0019] The advantages of adopting the above-mentioned further solution are that the process is simple, the winding angle and winding pitch of each turn of the refrigeration tube are reasonably designed, which effectively increases the contact degree and contact area between the refrigeration coil and the outer shell, greatly improves the efficiency of heat conduction, and ensures the uniformity of heat exchange.

[0020] Furthermore, step S3 includes the following specific steps: First, fill the foaming agent with low pressure, then fill the foaming agent with gradient pressure, and keep it at a constant temperature for 20-40 minutes.

[0021] The advantages of adopting the above-mentioned further scheme are that the process is simple and the design is reasonable, which can control the permeability of the foaming agent to below 8% and the effective heat exchange area retention rate ≥95%.

[0022] Further, the foaming agent is filled at a low pressure of 0.1-0.3 MPa until the coverage of the foaming agent reaches 90%, and then the pressure is increased at 0.05 MPa / s to a final pressure of 0.4-0.8 MPa.

[0023] The beneficial effect of adopting the above-mentioned further scheme is that the foaming agent is filled in the process by first low pressure and then gradient pressure, which is a more reasonable design. It can control the permeability of the foaming agent to below 8% and the effective heat exchange area retention rate ≥95%.

[0024] The present invention also relates to a shell-and-tube evaporator, which is manufactured using the manufacturing process described above, and includes a shell, a refrigeration coil and an inner composite insulation mechanism. The inner composite insulation mechanism is installed inside the shell and is filled with a foaming agent. The refrigeration coil is installed between the shell and the inner composite insulation mechanism, and its inner and outer sides are respectively attached to the inner wall of the shell and the outer wall of the inner composite insulation mechanism.

[0025] The beneficial effect of adopting the above-mentioned further solution is that the present invention also provides a shell-and-tube evaporator, in which the refrigerant flows in the refrigeration coil and absorbs heat to change from liquid to gas, so as to refrigerate the beverage in contact with the outer wall of the shell, and the refrigeration effect is better. During this process, the refrigerant inside the cooling coil exchanges heat with the beverage in contact with the outer wall of the casing. At the same time, the inner composite insulation mechanism is used for insulation to prevent the refrigerant from exchanging heat with the inner side of the casing and thus avoiding heat waste.

[0026] Furthermore, the inner composite insulation mechanism includes a vacuum insulation panel and a physical isolation barrier. The physical isolation barrier is installed inside the refrigeration coil, with its outer side fitting against the inner side of the refrigeration coil. The vacuum insulation panel is installed inside the physical isolation barrier, forming a filling space between it and the physical isolation barrier, and the foaming agent is filled into the filling space.

[0027] The advantages of adopting the above-mentioned further solution are that the structure is simple and the design is reasonable. It utilizes vacuum insulation panels and physical isolation barriers, and at the same time, it uses foaming agents to insulate the inside of the refrigeration coil, so as to avoid heat loss and affect the refrigeration effect.

[0028] The present invention also relates to a snow melting machine, including an outer cylinder and a shell-and-tube evaporator as described above, wherein the outer shell is installed inside the outer cylinder, and a channel for beverage flow is formed between the outer cylinder and the outer cylinder.

[0029] The beneficial effect of adopting the above-mentioned further solution is that the present invention also provides a snow melting machine. During the use of the snow melting machine, the refrigerant flows in the refrigeration coil and absorbs heat to change from liquid to gas, so as to cool the beverage in the outer cylinder, and the cooling effect is better. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the manufacturing process of the evaporator in this invention. Figure 2 This is a schematic diagram of the overall structure of the evaporator in this invention; Figure 3 This is a partial structural diagram of the evaporator in this invention; Figure 4 A schematic diagram of the servo-driven spiral winding device used in this invention for manufacturing a cooling coil; Figure 5 This is a schematic diagram showing the rotation direction when the servo-driven spiral winding device of the present invention is used to manufacture the cooling coil.

[0031] The attached diagram lists the components represented by each number as follows: 1. Outer shell; 2. Refrigeration coil; 3. Foaming agent; 4. Vacuum insulation panel; 5. Physical isolation barrier. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0034] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this technology based on the specific circumstances.

[0035] In the description of this application, spatial relation terms such as "below," "under," "below," "below," "above," "over," etc., are used herein to describe the relationship between one element or feature shown in the figures and other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figures is flipped, an element or feature described as "below" or "under" or "below" of other elements or features will be oriented "above" other elements or features. Therefore, the exemplary terms "below" and "under" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein are interpreted accordingly.

[0036] In the description of this application, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0037] Example 1 like Figures 1 to 5 As shown, this embodiment provides a manufacturing process for a shell-and-tube evaporator, including the following specific steps: S1: Fabricate cooling coil 2; S2: Place the refrigeration coil 2 into the outer casing 1, so that its outer side is in contact with the inner wall of the outer casing 1; at the same time, place the inner composite insulation mechanism into the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2. S3: Foaming agent 3 is filled into the cavity of the inner composite insulation mechanism under low pressure and then gradually increased pressure.

[0038] During the evaporator manufacturing process, S1: the refrigeration coil 2 is manufactured; S2: the refrigeration coil 2 is placed inside the outer shell 1, so that its outer side is in contact with the inner wall of the outer shell 1; at the same time, the inner composite insulation mechanism is placed inside the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2; S3: the foaming agent 3 is filled into the cavity of the inner composite insulation mechanism first at low pressure and then at a gradient pressure. The process is simple and effectively increases the contact area and contact degree between the refrigeration coil 2 and the outer shell 1, ensuring the uniformity of heat exchange.

[0039] Preferably, in this embodiment, the cooling coil 2 is cylindrical in shape and is adapted to the shape of the outer shell 1.

[0040] This embodiment features a simple process and a reasonable design. Through dynamic winding molding, gradient composite structure, and intelligent foaming process, it ensures the uniformity of heat exchange and solves the problems of uneven tube-shell gap, high contact thermal resistance, and foaming agent penetration in traditional evaporators, thereby achieving improved heat exchange efficiency and long-term stable operation.

[0041] Example 2 Based on Example 1, in this example, step S1 includes the following specific steps: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil 2, causing the refrigeration coil 2 to undergo 0.8%-1.2% plastic deformation.

[0042] The process is simple and the design is reasonable. It can realize the production of the cooling coil 2 and make the cooling coil 2 fit the inner surface of the outer shell 1, which greatly increases the contact area between the cooling coil 2 and the outer shell 1, thereby ensuring the uniformity of heat exchange.

[0043] Preferably, in this embodiment, the refrigeration pipe is a copper pipe.

[0044] Preferably, in this embodiment, the spiral winding device is preferably a servo-driven spiral winding device in the prior art, which is clockwise when manufacturing the cooling coil 2.

[0045] In addition, a servo-driven spiral winding device is used to achieve automatic compensation of the winding curvature of the copper tube based on the principle of metal memory effect. The metal memory effect (shape memory effect) refers to the property of certain alloys to recover their original shape at a specific temperature, which mainly stems from the property of their crystal structure changing with temperature.

[0046] Preferably, in this embodiment, a PID controller is used to control the servo-driven spiral winding device to wind the cooling tube during actual operation.

[0047] In addition, the aforementioned PID controller maintains a constant pretension (25±0.5N), thereby causing the cooling coil 2 to undergo 0.8%-1.2% plastic deformation.

[0048] Moreover, the aforementioned tension is monitored in real time by a tension sensor, and the data is fed back to the PID controller in real time; the PID controller outputs commands to the servo motor, with a response time of ≤10ms.

[0049] Based on the above solution, the above manufacturing process can increase the contact area between the cooling coil 2 and the outer casing 1 to 82%-90% of the theoretical value, and reduce the contact thermal resistance to 0.02m. 2 • Below K / W.

[0050] Example 3 Based on Example 2, in this example, the cross-section of each loop of the refrigeration tube is elliptical, and the ratio of the major axis to the minor axis of the elliptical cross-section is (0.5-2):0.6.

[0051] The process is simple, and the elliptical cross-section of each coil of the refrigeration tube is more reasonable, which greatly increases the contact area between the refrigeration coil 2 and the outer shell 1, ensuring the uniformity of heat exchange.

[0052] Preferably, in this embodiment, the cross-section of each coil of the cooling pipe is elliptical, and the ratio of the major axis to the minor axis of the elliptical cross-section is 1:0.6. Furthermore, the elliptical cross-section of each coil of the cooling pipe increases the contact area, resulting in better heat conduction.

[0053] In addition, each of the above-mentioned cooling tubes uses a copper tube with an elliptical cross-section. The major axis of the copper tube is 10mm and its minor axis is 6mm, with a major-to-minor axis ratio of 1:0.6, which increases the contact area by 40% compared to a round tube.

[0054] Alternatively, the cross-section of each of the aforementioned refrigerant coils may be elliptical, and the ratio of the major and minor axes of this elliptical cross-section may also be other suitable ratios, such as 2:0.6. In comparison, this ratio is not as suitable as the aforementioned 1:0.6, wherein the contact area between the outer casing 1 and the refrigerant coil 2 is smaller than that in the case where the ratio of the major and minor axes is 1:0.6.

[0055] Example 4 Based on any one of Embodiments 2 to 3, in this embodiment, before the spiral winding device winds the refrigeration tube, it further includes S0: performing a three-dimensional heat flow simulation to confirm the winding angle of each turn of the refrigeration tube and the winding pitch between two adjacent turns of the refrigeration tube.

[0056] This method is simple and reasonably designed. It uses a three-dimensional simulation model to simulate the specific situation of heat flow conduction under different winding angles and winding pitches, so as to determine the optimal winding angle and winding pitch of the cooling tube and ensure the uniformity of heat exchange.

[0057] Example 5 Based on Example 4, in this example, the winding angle of each turn of the refrigeration tube is 87°-88°, and the winding pitch between two adjacent turns of the refrigeration tube is 8-12mm.

[0058] The process is simple, and the winding angle and pitch of each turn of the cooling coil are reasonably designed, which effectively increases the contact degree and contact area between the cooling coil 2 and the outer shell 1, greatly improves the efficiency of heat conduction, and ensures the uniformity of heat exchange.

[0059] Preferably, in this embodiment, the winding angle of each turn of the refrigeration tube and the winding pitch between two adjacent turns of the refrigeration tube are as follows: Option 1: The winding angle of each turn of the refrigeration tube is 87°, and the winding pitch between two adjacent turns of the refrigeration tube is 8mm.

[0060] Option 2: The winding angle of each turn of the refrigeration tube is 87°, and the winding pitch between two adjacent turns of the refrigeration tube is 10mm.

[0061] Option 3: The winding angle of each turn of the refrigeration tube is 87°, and the winding pitch between two adjacent turns of the refrigeration tube is 12mm.

[0062] Option 4: The winding angle of each turn of the refrigeration tube is 88°, and the winding pitch between two adjacent turns of the refrigeration tube is 8mm.

[0063] Option 5: The winding angle of each turn of the refrigeration tube is 88°, and the winding pitch between two adjacent turns of the refrigeration tube is 10mm.

[0064] Option 6: The winding angle of each turn of the refrigeration tube is 88°, and the winding pitch between two adjacent turns of the refrigeration tube is 12mm.

[0065] Example 6 Based on the above embodiments, in this embodiment, step S3 includes the following specific steps: First, fill the foaming agent 3 under low pressure, then fill the foaming agent 3 under gradient pressure, and keep it at a constant temperature for 20-40 minutes.

[0066] The process is simple and reasonably designed, which can control the permeability of the foaming agent to below 8% and maintain the effective heat exchange area retention rate at ≥95%.

[0067] Preferably, in this embodiment, the foaming agent 3 is first filled with low pressure, and then the foaming agent 3 is filled with gradient pressure and kept at a constant temperature for 30 minutes.

[0068] Alternatively, the foaming agent 3 can be filled with low pressure first, and then the foaming agent 3 can be filled with gradient pressure and kept at a constant temperature for 20 or 40 minutes, depending on the actual needs.

[0069] Example 7 Based on Example 6, in this example, the foaming agent 3 is filled at a low pressure of 0.1-0.3 MPa until the coverage of the foaming agent 3 reaches 90%, and then the pressure is increased at 0.05 MPa / s to a final pressure of 0.4-0.8 MPa.

[0070] In this process, the foaming agent is filled using a method of first applying low pressure and then gradually increasing the pressure. This design is quite reasonable and can control the permeability of the foaming agent to below 8%, while maintaining an effective heat exchange area retention rate of ≥95%.

[0071] Based on the above scheme, the pressure gradient pressurization rate is 0.05 MPa / s, and the effective heat exchange area retention rate after curing is ≥95%.

[0072] In addition, the heat exchange capacity per unit area of ​​the evaporator is ≥2800W / m². 2 The uniformity of frost layer thickness is ≥90%.

[0073] Example 8 Based on the above embodiments, this embodiment also provides a shell-and-tube evaporator, which is manufactured using the manufacturing process described above. It includes an outer shell 1, a refrigeration coil 2, and an inner composite insulation mechanism. The inner composite insulation mechanism is installed inside the outer shell 1 and is filled with a foaming agent 3. The refrigeration coil 2 is installed between the outer shell 1 and the inner composite insulation mechanism, and its inner and outer sides are respectively attached to the inner wall of the outer shell 1 and the outer wall of the inner composite insulation mechanism.

[0074] Preferably, in this embodiment, the surface of the refrigeration coil 2 is coated with a nano-anti-corrosion coating with a thickness of 20-50μm, which improves corrosion resistance by ≥70% and is compatible with R404A / R290 environmentally friendly refrigerant.

[0075] Preferably, in this embodiment, the outer shell 1 has a cylindrical structure.

[0076] In addition, the outer shell 1 has a cylindrical structure that is thin at one end and thick at the other end, and the thin end of the outer shell 1 is closed while the thick end is open, which facilitates the assembly of various components.

[0077] Moreover, the outer surface of the aforementioned shell 1 is a "beverage contact heat exchange surface" with micron-level grooves to enhance turbulence; and the inner surface of the shell 1 is a "spiral winding bonding surface" with a surface roughness Ra≤1.6μm.

[0078] This embodiment also provides a shell-and-tube evaporator. In use, the refrigerant flows in the refrigeration coil 2 and absorbs heat to change from liquid to gas, so as to cool the beverage in contact with the outer wall of the outer shell 1, and the cooling effect is better. During this process, the refrigerant in the cooling coil 2 exchanges heat with the beverage in contact with the outer wall of the outer shell 1. At the same time, the inner composite insulation mechanism is used for insulation treatment to avoid heat waste caused by heat exchange between the refrigerant and the inner side of the outer shell.

[0079] Example 9 Based on Example 8, in this example, the inner composite insulation mechanism includes a vacuum insulation board 4 and a physical isolation barrier 5. The physical isolation barrier 5 is installed inside the refrigeration coil 2, and its outer side is attached to the inner side of the refrigeration coil 2. The vacuum insulation board 4 is installed inside the physical isolation barrier 5, and a filling space is formed between it and the physical isolation barrier 5. The foaming agent 3 is filled in the filling space.

[0080] The solution has a simple structure and reasonable design. It uses vacuum insulation board 4 and physical isolation barrier 5, along with foaming agent 3, to insulate the inside of the refrigeration coil 2 and avoid heat loss that could affect the refrigeration effect.

[0081] Preferably, in this embodiment, the physical isolation barrier 5 is preferably a silicone membrane. The heat-insulating silicone achieves a closed-cell rate of >92% through a porous structure (such as 30%-40% alkali-free glass wool), with a heat transfer coefficient as low as 0.03 W / (m·K), resulting in excellent heat insulation performance.

[0082] Preferably, in this embodiment, the thickness of the silicone diaphragm is preferably 0.5 mm, and it is tightly attached to the outside of the refrigeration coil 2.

[0083] Preferably, in this embodiment, the silicone diaphragm is a cylindrical structure that is thin at one end and thick at the other, with both ends open.

[0084] In addition, the thin end face of the silicone diaphragm is attached to the closed end of the outer shell 1, and the outer surface of its thick end is attached to the inner surface of the outer shell 1. At this time, an installation space is formed between the silicone diaphragm and the outer shell 1. The cooling coil 2 is installed in the installation space, and its two sides are attached to the inner surface of the outer shell 1 and the outer surface of the silicone diaphragm, respectively.

[0085] Moreover, the aforementioned silicone diaphragm is in close contact with the refrigeration coil 2 and can withstand temperatures ≥150℃.

[0086] Preferably, in this embodiment, the vacuum insulation panel 4 is preferably cylindrical in shape, located at the center of the outer shell 1 and coaxially distributed with the outer shell 1, and the foaming agent 3 is distributed in the area between the vacuum insulation panel 4 and the silicone diaphragm.

[0087] In addition, the aforementioned vacuum insulation panel 4 has a thickness of 5mm and covers an area of ​​30% of the outer shell diameter; Preferably, in this embodiment, the foaming agent 3 is preferably microporous aerogel. Microporous aerogel has excellent thermal insulation performance, and its thermal conductivity can be as low as 0.012 W / (m·K), which is much lower than that of traditional thermal insulation materials, resulting in better thermal insulation effect.

[0088] In addition, the density of the aforementioned microporous aerogel is 150 kg / m³. 3 Thermal conductivity ≤0.018W / (m·K).

[0089] Moreover, the gap between the inner composite insulation mechanism and the inner wall of the outer shell is ≤0.1mm.

[0090] Example 10 Based on the above embodiments, this embodiment also provides a snow melting machine, including an outer cylinder and a shell-and-tube evaporator as described above. The outer shell 1 is installed inside the outer cylinder, and a channel for beverage flow is formed between the outer shell 1 and the outer cylinder.

[0091] Preferably, in this embodiment, the outer cylinder has a cylindrical structure, the entire evaporator is installed inside the outer cylinder, and a beverage storage space is reserved between the outer cylinder and the outer shell 1.

[0092] During use, the refrigerant flows inside the refrigeration coil 2 and absorbs heat to change from a liquid state to a gas state, thereby cooling the beverage that is in contact with the outer wall of the outer casing 1, resulting in a better cooling effect. During this process, the refrigerant in the cooling coil 2 exchanges heat with the beverage in contact with the outer wall of the outer shell 1. At the same time, the inner composite insulation mechanism is used for insulation treatment to avoid heat waste caused by heat exchange between the refrigerant and the inner side of the outer shell.

[0093] This embodiment also provides a snow melting machine. During use, the refrigerant flows in the refrigeration coil 2 and absorbs heat to change from liquid to gas, thereby cooling the beverage in the outer cylinder, resulting in a better cooling effect.

[0094] This invention provides a shell-and-tube evaporator and its manufacturing process, which includes the following specific steps: S0: Three-dimensional heat flow simulation confirmed that the winding angle range of each turn of the cooling tube is 87°-88°, and the winding pitch range between two adjacent turns of the cooling tube is 8-12mm. S1: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil 2. The PID control system maintains a constant pretension (25±0.5N) to cause the refrigeration coil 2 to undergo 0.8%-1.2% plastic deformation. S2: Place the refrigeration coil 2 into the outer casing 1, so that its outer side is in contact with the inner wall of the outer casing 1; at the same time, place the inner composite insulation mechanism into the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2. S3: Fill the foaming agent 3 at a low pressure of 0.1-0.3MPa until the coverage of the foaming agent 3 reaches 90%, and then increase the pressure to a final pressure of 0.4-0.8MPa at a pressure of 0.05MPa / s.

[0095] In actual evaporator manufacturing, the specific implementation method is as follows: Example 1 This embodiment provides a shell-and-tube evaporator and its manufacturing process, which includes the following specific steps: S0: Three-dimensional heat flow simulation confirmed that the winding angle range of each turn of the cooling tube is 87°, and the winding pitch range between two adjacent turns of the cooling tube is 8mm. S1: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil 2. The PID control system maintains a constant pretension (25±0.5N) to cause the refrigeration coil 2 to undergo 0.8% plastic deformation. S2: Place the refrigeration coil 2 into the outer casing 1, so that its outer side is in contact with the inner wall of the outer casing 1; at the same time, place the inner composite insulation mechanism into the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2. S3: Fill the foaming agent 3 at a low pressure of 0.1 MPa until the coverage of the foaming agent 3 reaches 90%, and then increase the pressure to a final pressure of 0.4 MPa at a pressure of 0.05 MPa / s.

[0096] Example 2 This embodiment provides a shell-and-tube evaporator and its manufacturing process, which includes the following specific steps: S0: Three-dimensional heat flow simulation confirmed that the winding angle range of each turn of the cooling tube is 88°, and the winding pitch range between two adjacent turns of the cooling tube is 12mm. S1: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil 2. The PID control system maintains a constant pretension (25±0.5N) to cause the refrigeration coil 2 to undergo 1.2% plastic deformation. S2: Place the refrigeration coil 2 into the outer casing 1, so that its outer side is in contact with the inner wall of the outer casing 1; at the same time, place the inner composite insulation mechanism into the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2. S3: Fill the foaming agent 3 at a low pressure of 0.3MPa until the coverage of the foaming agent 3 reaches 90%, and then increase the pressure to a final pressure of 0.8MPa at a pressure of 0.05MPa / s.

[0097] Example 3 This embodiment provides a shell-and-tube evaporator and its manufacturing process, which includes the following specific steps: S0: Three-dimensional heat flow simulation confirmed that the winding angle range of each turn of the cooling tube is 87°, and the winding pitch range between two adjacent turns of the cooling tube is 10mm. S1: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil 2. The PID control system maintains a constant pretension (25±0.5N) to cause the refrigeration coil 2 to undergo 1.0% plastic deformation. S2: Place the refrigeration coil 2 into the outer casing 1, so that its outer side is in contact with the inner wall of the outer casing 1; at the same time, place the inner composite insulation mechanism into the refrigeration coil 2, so that its outer side is in contact with the inner side of the refrigeration coil 2. S3: Fill the foaming agent 3 at a low pressure of 0.2 MPa until the coverage of the foaming agent 3 reaches 90%, and then increase the pressure to a final pressure of 0.6 MPa at a pressure of 0.05 MPa / s.

[0098] This invention relates to a shell-and-tube evaporator, its manufacturing process, and a snow melting machine. The process is simple and rationally designed. Through dynamic winding molding, gradient composite structure, and intelligent foaming process, it ensures the uniformity of heat exchange and solves the problems of uneven shell-and-tube gap, high contact thermal resistance, and foaming agent penetration in traditional evaporators, thereby achieving improved heat exchange efficiency and long-term stable operation.

[0099] In addition, the present invention has the following advantages: (1) Energy efficiency improvement: heat exchange per unit area ≥2800W / m 2 Energy efficiency ratio improved by 42%; (2) Operational stability: Frost layer thickness uniformity ≥90%; (3) Long-lasting and durable: Service life of up to 10 years (traditional products 5-6 years), reducing overall operating costs by 35%.

[0100] This invention relates to the field of refrigeration equipment technology, specifically disclosing a high-efficiency shell-and-tube evaporator for snow melting machines based on spiral winding molding technology and its preparation method. Addressing the shortcomings of traditional evaporators, such as uneven shell-and-tube gaps, high contact thermal resistance, and the impact of foaming agent penetration on heat exchange, this invention achieves breakthroughs through three core technologies: 1. Dynamic winding molding process: A servo-driven spiral winding device is used, and a constant pretension (25±0.5N) is applied through PID closed-loop control, causing the copper tube to undergo 0.8%-1.2% plastic deformation. Combined with the metal memory effect, this achieves a tight fit between the tube and the shell, increasing the contact area to 82%-90% of the theoretical value and reducing the contact thermal resistance to 0.02 μm. 2 K / W or less; 2. Gradient composite structure design: The innovative use of elliptical cross-section copper tubes (length-to-short axis ratio 1:0.6), combined with optimized winding parameters (pitch 8-12mm, angle 87°-88°) and zoned insulation structure (vacuum insulation board and aerogel composite layer) significantly improves heat exchange uniformity. 3. Intelligent foaming control technology: By using physical isolation barriers and a two-step gradient pressurization process, the permeability of the foaming agent is controlled to within 8%, ensuring that the effective heat exchange area retention rate is ≥95%.

[0101] This invention achieves a 42% increase in evaporator energy efficiency and a frost uniformity of over 90%. It is compatible with new environmentally friendly refrigerants and has passed international certification. It can be widely used in food cold chain and industrial refrigeration equipment and has significant market competitiveness.

[0102] While embodiments or examples of this disclosure have been described with reference to the accompanying drawings, it should be understood that the above embodiments are merely exemplary embodiments or examples, and the scope of the invention is not limited by these embodiments or examples, but only by the granted claims and their equivalents. Various elements in the embodiments or examples may be omitted or replaced by their equivalents. Furthermore, the steps may be performed in a different order than that described in this disclosure. Further, various elements in the embodiments or examples may be combined in various ways. Importantly, as the technology evolves, many elements described herein can be replaced by equivalents that appear after this disclosure.

Claims

1. A manufacturing process for a shell-and-tube evaporator, characterized in that, The specific steps include the following: S1: Make the refrigeration coil (2); S2: Place the refrigeration coil (2) into the outer shell (1) so that its outer side is in contact with the inner wall of the outer shell (1); at the same time, place the inner composite insulation mechanism into the refrigeration coil (2) so that its outer side is in contact with the inner side of the refrigeration coil (2); S3: The foaming agent (3) is first filled into the cavity of the inner composite insulation mechanism under low pressure and then under gradient pressure.

2. The manufacturing process of the shell-and-tube evaporator according to claim 1, characterized in that, S1 includes the following specific steps: The refrigeration tube is wound using a spiral winding device to form the refrigeration coil (2), causing the refrigeration coil (2) to undergo 0.8%-1.2% plastic deformation.

3. The manufacturing process of the shell-and-tube evaporator according to claim 2, characterized in that, Each loop of the cooling tube has an elliptical cross-section with a major-minor axis ratio of (0.5-2):0.

6.

4. The manufacturing process of the shell-and-tube evaporator according to claim 2, characterized in that, Before the spiral winding device winds the refrigeration tube, it also includes S0: performing a three-dimensional heat flow simulation to confirm the winding angle of each turn of the refrigeration tube and the winding pitch between two adjacent turns of the refrigeration tube.

5. The manufacturing process of the shell-and-tube evaporator according to claim 4, characterized in that, The winding angle of each turn of the refrigeration tube is 87°-88°, and the winding pitch between two adjacent turns of the refrigeration tube is 8-12mm.

6. The manufacturing process of the shell-and-tube evaporator according to any one of claims 1-5, characterized in that, S3 includes the following specific steps: First, fill the foaming agent (3) with low pressure, then fill the foaming agent (3) with gradient pressure, and keep it at a constant temperature for 20-40 minutes.

7. The manufacturing process of the shell-and-tube evaporator according to claim 6, characterized in that, The foaming agent (3) is filled at a low pressure of 0.1-0.3 MPa until the coverage of the foaming agent (3) reaches 90%, and then the pressure is increased at 0.05 MPa / s to a final pressure of 0.4-0.8 MPa.

8. A shell-and-tube evaporator, characterized in that, The product is manufactured using the manufacturing process described in any one of claims 1-7, and includes an outer shell (1), a refrigeration coil (2), and an inner composite insulation mechanism. The inner composite insulation mechanism is installed inside the outer shell (1) and is filled with a foaming agent (3). The refrigeration coil (2) is installed between the outer shell (1) and the inner composite insulation mechanism, and its inner and outer sides are respectively attached to the inner wall of the outer shell (1) and the outer wall of the inner composite insulation mechanism.

9. The shell-and-tube evaporator according to claim 8, characterized in that, The inner composite insulation mechanism includes a vacuum insulation board (4) and a physical isolation barrier (5). The physical isolation barrier (5) is installed inside the refrigeration coil (2), and its outer side is attached to the inner side of the refrigeration coil (2). The vacuum insulation board (4) is installed inside the physical isolation barrier (5), and a filling space is formed between it and the physical isolation barrier (5). The foaming agent (3) is filled in the filling space.

10. A snow melting machine, comprising an outer cylinder, characterized in that, It also includes a shell-and-tube evaporator as described in any one of claims 8-9, wherein the outer shell (1) is installed inside the outer cylinder, and a beverage flow channel is formed between the outer shell and the outer cylinder.

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