Preparation device of vacuum insulated panel

Abstract

The utility model relates to the technical field of vacuum insulation panel preparation, and provides a vacuum insulation panel preparation device which comprises a packaging bag, a vacuumizing piece and an extrusion assembly. A placing cavity for accommodating a core material is formed in the packaging bag; the vacuumizing part is used for vacuumizing the packaging bag filled with the core material; and the extrusion assembly is used for extruding the packaging bag filled with the core material. According to the preparation device of the vacuum insulation panel, the vacuumizing efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of vacuum insulation panel preparation, and in particular to a device for preparing vacuum insulation panels. Background Art

[0002] Vacuum insulation panels are commonly used in manufacturing equipment such as refrigerators. In related technologies, vacuum insulation panels are manufactured by evacuating a packaging bag with a vacuum pump to compress the core material. However, once a certain vacuum level is reached, the gas flow within the packaging bag is affected by the Knudsen effect, slowing the rate at which the vacuum level decreases. Utility Model Content

[0003] In view of this, an embodiment of the present application hopes to provide a device for preparing a vacuum insulation panel, which can improve the efficiency of vacuuming.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the embodiment of the present application is implemented as follows:

[0005] The present application discloses a device for preparing a vacuum insulation panel, comprising:

[0006] A packaging bag, wherein the packaging bag is formed with a placement cavity for accommodating the core material;

[0007] A vacuum pump, used for vacuuming the packaging bag containing the core material;

[0008] An extrusion assembly is used to extrude the packaging bag containing the core material.

[0009] In one embodiment, the extrusion assembly includes:

[0010] A clamping plate assembly comprising a first plate and a second plate, wherein one of the first plate and the second plate is used to support the packaging bag, and the other of the first plate and the second plate is used to squeeze the packaging bag;

[0011] The distance-changing assembly is configured to adjust the distance between the first plate and the second plate along a distance-changing direction so as to squeeze or loosen the packaging bag.

[0012] In one embodiment, the pitch-changing assembly includes:

[0013] a transmission member, wherein the first plate is disposed on the transmission member;

[0014] An adjusting member is drivingly connected to the transmission member, and the transmission member is configured to be able to drive the first plate to approach or move away from the second plate along the pitch changing direction under the drive of the adjusting member.

[0015] In one embodiment, the transmission member has a plurality of installation positions along the pitch changing direction, and the first plate is detachably arranged at one of the plurality of installation positions.

[0016] In one embodiment, there are multiple clamping plate assemblies, and the multiple clamping plate assemblies are spaced apart along the pitch changing direction. The pitch changing assembly is used to control the multiple clamping plate assemblies to squeeze the multiple packaging bags.

[0017] In one embodiment, the core material is an inorganic glass fiber core material.

[0018] In one embodiment, the squeezing component periodically squeezes the packaging bag.

[0019] In one embodiment, the periodic extrusion is: the number of extrusions is not less than 5 times, and the frequency of extrusion is not less than 3 times per minute.

[0020] In one embodiment, the maximum compressive strain that the core material can withstand is not less than 30%.

[0021] In one embodiment, the packaging bag is formed with a seal communicating with the placement cavity, and the preparation device includes a seal member, which is used to seal the seal.

[0022] In one embodiment, the volume of the core material before being placed in the packaging bag is the initial volume, the volume of the core material after being sealed is the compressed volume, and the ratio of the initial volume to the compressed volume is not less than 2.

[0023] In one embodiment, the packaging bag comprises a heat-sealing layer.

[0024] In one embodiment, the heat sealing layer is made of polyethylene.

[0025] The present application discloses an apparatus for preparing a vacuum insulation panel. By providing a vacuum pump, a packaging bag containing a core material can be vacuumed. This reduces the number of gas molecules within the packaging bag, resulting in a larger molecular free path and smaller pore size. This reduces the effect of gas conduction on insulation and improves the insulation effect. By providing an extrusion assembly, a packaging bag containing a core material can be extruded. The extrusion of the extrusion assembly accelerates the gas flow rate within the packaging bag, thereby improving the efficiency of vacuuming, reducing the time required for vacuuming, and improving the manufacturing efficiency of the vacuum insulation panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic structural diagram of a device for preparing a vacuum insulation panel provided in an embodiment of the present application, wherein there are multiple clamping plate assemblies;

[0027] Figure 2A schematic structural diagram of a vacuum insulation panel provided in another embodiment of the present application, wherein the core material is in an uncompressed state;

[0028] Figure 3 This is a schematic structural diagram of a vacuum insulation panel provided in yet another embodiment of the present application, wherein the core material is in a compressed state.

[0029] Description of Reference Numerals

[0030] 100. Apparatus for preparing a vacuum insulation panel; 1. Packaging bag; 1a. Placement cavity; 1b. Sealing member; 1c. Extrusion surface; 2. Extrusion assembly; 21. Clamping plate assembly; 211. First plate; 212. Second plate; 22. Variable pitch assembly; 221. Transmission member; 222. Adjusting member; 3. Sealing member; A. Core material; B. Vacuum insulation panel. DETAILED DESCRIPTION

[0031] It should be noted that, unless there is a conflict, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed description in the specific implementation method should be understood as an explanation of the purpose of this application and should not be regarded as an improper restriction on this application.

[0032] The present application is further described in detail below with reference to the accompanying drawings and specific embodiments. The descriptions of "first", "second", etc. in the embodiments of the present application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly including at least one feature. In the description of the embodiments of the present application, the meaning of "multiple" is at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0033] The present invention provides a vacuum insulation panel manufacturing device 100. Figures 1 to 3 The preparation device includes a packaging bag 1, a vacuum pump (not shown), and an extrusion assembly 2. The packaging bag 1 is formed with a placement cavity 1a for accommodating the core material A. The vacuum pump is used to evacuate the packaging bag 1 containing the core material A. The extrusion assembly 2 is used to extrude the packaging bag 1 containing the core material A.

[0034] Exemplarily, the core material A has a porous structure.

[0035] It should be noted that vacuum insulation panel B, as a new generation of thermal insulation technology, uses micro-nano composite core material A as its filler, exhibiting excellent thermal insulation capabilities and achieving a thermal conductivity below 3mW / (mK). In addition to core material A's inherently low bulk thermal conductivity, the larger molecular free path and pore size of core material A in a vacuum state significantly contribute to thermal insulation by isolating gas conduction. Therefore, reducing the vacuum level of vacuum insulation panel B in a relatively short period of time is crucial for improving the performance and mass production efficiency of vacuum machine insulation panels. However, at a certain vacuum level, the gas flow within core material A's porous structure is affected by the Knudsen effect, which significantly slows the efficiency of vacuum reduction.

[0036] The vacuum insulation panel preparation device 100 provided in the present application can protect the core material A located in the placement cavity 1a and provide a relatively closed environment by setting a packaging bag 1, so as to isolate the material exchange between the core material A and the external environment, such as gas, water seal, etc., and reduce the impact of the entry of the core material A into the placement cavity 1a, thereby improving the stability and durability of the vacuum insulation panel B.

[0037] By setting up a vacuum pump, the packaging bag 1 containing the core material A can be vacuumed. In this way, the gas molecules in the packaging bag 1 can be reduced, so that the gas molecules have a larger molecular free path and a smaller pore size. In this way, the influence of gas conduction on thermal insulation can be reduced and the thermal insulation effect can be improved.

[0038] By setting up the extrusion component 2, the packaging bag 1 containing the core material A can be extruded. In this way, under the extrusion of the extrusion component 2, the gas flow rate in the packaging bag 1 can be accelerated, thereby improving the efficiency of vacuuming, reducing the time required for vacuuming, and improving the manufacturing efficiency of the vacuum insulation panel B.

[0039] It is understandable that the vacuum insulation panel B is difficult to achieve a low vacuum and has a slow vacuuming rate because the gas molecules in the packaging bag 1 cannot be effectively removed under low pressure. The Knudsen number is defined by the following formula:

[0040]

[0041] Where l is the molecular free path, which is affected by gas type and pressure; δ is the pore size of the core material. K is the Boltzmann constant, T is the temperature, d g is the diameter of the gas molecules, and P is the pressure. The larger Kn is, the thinner the gas is, the smaller the probability of collision between gas molecules is, and the greater the probability of gas molecules interacting with the pores of core material A.

[0042] At normal pressure, the molecular free path is nanometer-sized, far smaller than the pore size of core material A. That is, Kn is far less than 1, so the influence of the Knudsen effect can be ignored. As the pressure decreases, the molecular free path increases, and Kn increases. As the molecular free path approaches the pore size of core material A, that is, Kn approaches 1, the influence of the Knudsen effect becomes more pronounced.

[0043] The embodiment of the present application uses an extrusion device to extrude the packaging bag 1 containing the core material A to reduce the volume of the core material A area where the gas flow is restricted, thereby temporarily increasing the pressure. The Kn number can decrease as the pressure increases, which means that the gas flow efficiency is higher, thereby achieving the purpose of improving the vacuum efficiency.

[0044] For example, in one embodiment, please refer to Figure 1 and Figure 3 The outer surface of the packaging bag 1 has an extrusion surface 1c, and the extrusion component 2 can extrude the packaging bag 1 through the extrusion surface 1c.

[0045] In one embodiment, core material A is an inorganic glass fiber core material A. Inorganic glass fiber core material A is used here because, on the one hand, it has high mechanical strength and can withstand the extrusion of the extrusion assembly 2 without being easily damaged. This allows the vacuum insulation panel B prepared therefrom to have a lower vacuum degree and better insulation effect. Furthermore, compared to other core materials A, inorganic glass fiber core material A has a lower thermal conductivity, which can effectively prevent heat transfer, thereby improving the thermal insulation performance of the vacuum insulation panel B.

[0046] In one embodiment, the maximum compressive strain that the core material A can withstand is not less than 30%. That is to say, the core material A can withstand a maximum compressive strain of not less than 30% without structural damage. Exemplarily, the maximum compressive strain that the core material A can withstand can be 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65% or 70%, etc. Here, by selecting a core material A that can withstand a suitable compressive strain, on the one hand, the core material A can be reduced from being tightly filled in the packaging bag 1 under the cooperation of the vacuum part and the extrusion component 2, reducing the gaps in the packaging bag 1 and the movement space of the gas molecules, thereby more effectively preventing heat from being transferred through gas conduction and convection; on the other hand, it can withstand the extrusion from the extrusion component 2 well, reducing the occurrence of structural damage.

[0047] In one embodiment, please refer to Figure 1The squeezing assembly 2 includes a clamping plate assembly 21 and a pitch-changing assembly 22. The clamping plate assembly 21 includes a first plate 211 and a second plate 212. One of the first plate 211 and the second plate 212 is used to support the packaging bag 1, and the other of the first plate 211 and the second plate 212 is used to squeeze the packaging bag 1. The pitch-changing assembly 22 is configured to adjust the distance between the first plate 211 and the second plate 212 along the pitch-changing direction to squeeze or loosen the packaging bag 1.

[0048] For example, the packaging bag 1 can be placed on the second plate 212, and the first plate 211 is used to press the packaging bag 1. Alternatively, the packaging bag 1 can be placed on the first plate 211, and the second plate 212 is used to press the packaging bag 1. In other words, one of the first plate 211 and the second plate 212 is a carrier plate, and the other of the first plate 211 and the second plate 212 is a pressing plate. The packaging bag 1 is placed on the carrier plate, and the pressing plate is used to press the packaging bag 1 on the carrier plate.

[0049] Here, by setting the variable distance component 22 and the clamping plate component 21, the variable distance component 22 can adjust the distance between the first plate 211 and the second plate 212 along the variable distance direction. When it is necessary to squeeze the packaging bag 1, the variable distance component 22 can be used to adjust the first plate 211 and the second plate 212 to move toward each other along the variable distance direction to squeeze the packaging bag 1 in a vacuum state. In this way, the volume of the core material A area where the gas flow in the packaging bag 1 is restricted can be reduced, so that the pressure can be temporarily increased and the discharge of the gas in the packaging bag 1 can be accelerated. After squeezing, the variable distance component 22 can be used to adjust the first plate 211 and the second plate 212 to move away from each other along the variable distance direction. At this time, the elasticity of the core material A can be used to restore it to its original volume, and the pore size of the core material A is increased to obtain a lower pressure in the pore, high vacuum efficiency, and fast manufacturing efficiency.

[0050] By using mechanical components to squeeze the packaging bag 1 , not only can human squeezing errors be reduced and squeezing accuracy be improved, but the manufacturing efficiency of the vacuum insulation panel B can also be further improved.

[0051] For example, in one embodiment, the shape of the first plate 211 is not limited. For example, the first plate 211 may be rectangular, square, or circular.

[0052] For example, in one embodiment, the shape of the second plate 212 is not limited. For example, the first plate 211 may be rectangular, square, or circular.

[0053] Exemplarily, in one embodiment, along the projection in the variable pitch direction, the projection area of ​​the packaging bag 1 is located within the projection areas of the first plate 211 and the second plate 212 , thereby improving the uniformity of extrusion.

[0054] For example, in one embodiment, the pitch changing direction may be an up-down direction, that is, the first plate 211 may be disposed above the second plate 212 or the first plate 211 may be disposed below the second plate 212 .

[0055] It should be noted that "up" refers to the direction toward the ceiling, while "down" is the opposite of "up." The up-down, front-back, and left-right directions are mutually perpendicular and together form a three-dimensional vertical coordinate system.

[0056] For example, in one embodiment, Figure 1 R1 in can be the pitch change direction.

[0057] In one embodiment, please refer to Figure 1 The pitch-changing assembly 22 includes a transmission member 221 and an adjustment member 222. The first plate 211 is disposed on the transmission member 221. The adjustment member 222 is drivingly connected to the transmission member 221. The transmission member 221 is configured to move the first plate 211 toward or away from the second plate 212 along the pitch-changing direction under the drive of the adjustment member 222.

[0058] In this way, when the packaging bag 1 needs to be squeezed, the transmission member 221 can be driven by the adjusting member 222 to drive the first plate 211 to move along the variable pitch direction to approach and squeeze the packaging bag 1 on the second plate 212 or move away from and release the packaging bag 1 on the second plate 212. The degree of automation is high, the vacuuming rate is fast, and the adjusting member 222 can adjust the movement accuracy of the first plate 211 on the transmission member 221 according to needs to achieve different squeezing effects.

[0059] For example, in one embodiment, the adjusting member 222 may be a cylinder or a hydraulic motor, the transmission member 221 may be a telescopic rod, the first plate 211 is disposed on the telescopic rod, and the telescopic rod is driven to extend and retract by the cylinder or hydraulic motor to drive the first plate 211 to move.

[0060] In one embodiment, the transmission member 221 has a plurality of installation positions along the pitch changing direction, and the first plate 211 is detachably disposed at one of the plurality of installation positions.

[0061] In this way, the installation position of the first plate 211 can be adjusted according to the sizes of different packaging bags 1, so that packaging bags 1 of different sizes can obtain the same compression, which has good flexibility.

[0062] In one embodiment, please refer to Figure 1 There are multiple clamping plate assemblies 21, and the multiple clamping plate assemblies 21 are arranged at intervals along the variable pitch direction. The variable pitch assembly 22 is used to control the multiple clamping plate assemblies 21 to squeeze the multiple packaging bags 1.

[0063] Exemplarily, the number of the splint assemblies 21 can be three, and the three splint assemblies 21 are arranged at intervals along the pitch direction. The first plate 211 in each splint assembly 21 can be arranged on the transmission member 221, and the second plate 212 in each splint assembly 21 is fixedly arranged on one side of the corresponding first plate 211 along the pitch direction.

[0064] In this way, by setting up multiple clamping plate assemblies 21, a packaging bag 1 can be placed in each clamping plate assembly 21, and then multiple packaging bags 1 can be squeezed at one time through the variable distance assembly 22. In this way, the manufacturing efficiency of the vacuum insulation panel B can be greatly improved.

[0065] In one embodiment, the pressing assembly 2 presses the packaging bag 1 periodically.

[0066] For example, the transmission member 221 may be driven by the adjusting member 222 to drive the first plate 211 to periodically approach the second plate 212 to squeeze the packaging bag 1 and move away from the second plate 212 to release the packaging bag 1 .

[0067] In this way, by periodically squeezing the packaging bag 1, the gas pressure increases when the packaging bag 1 is squeezed, reducing the Kn number, thereby improving the efficiency of gas molecule discharge. When the packaging bag 1 is released, the core material A will return to the unpressurized state due to its own elasticity, so that the pore size will increase compared to the compressed state, thereby obtaining a lower pore pressure and achieving a step-by-step decrease in the number of gas molecules inside the core material A.

[0068] In one embodiment, the periodic extrusion is as follows: the number of extrusions is not less than 5 times, and the frequency of extrusion is not less than 3 times per minute.

[0069] For example, the number of extrusions can be 5, 6, 7, 8, 9, or 10. The extrusion frequency can be 3 times per minute, 4 times per minute, 5 times per minute, or 6 times per minute, etc. By setting an appropriate number of extrusions and extrusion frequency, periodic reciprocating extrusion can be achieved, thereby further accelerating the exhaust efficiency of the gas in the packaging bag 1, improving the vacuum extraction efficiency, and accelerating the manufacturing efficiency of the vacuum insulation panel B.

[0070] In one embodiment, please refer to Figures 1 to 3 The packaging bag 1 is formed with a sealing opening 1b communicating with the placement cavity 1a, and the preparation device includes a sealing member 3, which is used to seal the sealing opening 1b.

[0071] For example, the vacuuming member can vacuum the packaging bag 1 through the sealing opening 1 b. After the vacuum degree in the packaging bag 1 reaches a set pressure, the sealing member 3 can be used to seal the sealing opening 1 b.

[0072] Here, by setting a sealing member 3, the sealing 1b on the packaging bag 1 can be sealed. In this way, the entry of external air, moisture, dust and other impurities into the packaging bag 1 can be reduced, thereby effectively protecting the core material A from contamination and damage, maintaining the sealing and pressure in the packaging bag 1 for a long time, and improving the manufacturing efficiency of the vacuum insulation panel B.

[0073] Exemplarily, in one embodiment, the sealing member 3 may be a sealing strip.

[0074] In one embodiment, the volume of the core material A before being placed in the packaging bag 1 is the initial volume, and the volume of the core material A after being sealed at the seal 1b is the compressed volume. The ratio of the initial volume to the compressed volume is not less than 2.

[0075] In this way, by setting a suitable compression ratio, the core material A can still work stably after being vacuumed and extruded by the extrusion assembly 2, and the suitable compression ratio makes the thermal insulation capacity of the vacuum insulation panel B better.

[0076] In one embodiment, the packaging bag 1 includes a heat-sealing layer. By providing the heat-sealing layer, the packaging bag 1 can be heat-sealed at high temperatures, thereby effectively isolating the packaging bag from external oxygen, moisture, etc., reducing contamination and deterioration of the core material A and improving the working stability of the core material A.

[0077] In one embodiment, the heat-sealing layer is made of polyethylene. Polyethylene is used as the heat-sealing layer because, on the one hand, polyethylene is a thermoplastic with a certain degree of crystallinity and intermolecular forces. Under heating conditions, protons between polyethylene molecular chains can interchange, forming a tough bonding layer, thereby achieving a reliable seal. On the other hand, polyethylene has good chemical inertness and can effectively resist corrosion by acids, alkalis, and other chemicals. Furthermore, polyethylene has excellent cold resistance. When the vacuum insulation panel B is used in refrigeration equipment, polyethylene can maintain good sealing properties in low-temperature environments.

[0078] For example, in one embodiment, taking the preparation of a vacuum insulation panel B whose core material A is inorganic glass fiber as an example, a core material A that can withstand a maximum compressive strain of 50% is selected, the core material A is placed in the packaging bag 1 and fixed on the second plate 212, and then the transmission member 221 is driven by the adjustment member 222 to drive the first plate 211 away from the second plate 212 along the variable pitch direction, and the vacuum member begins to vacuum the packaging bag 1 through the seal 1b.

[0079] After the pressure inside the packaging bag 1 reaches 1 kPa, the adjusting member 222 drives the transmission member 221 to cause the first plate 211 to periodically squeeze the packaging bag 1 along the variable pitch direction. The maximum compressive strain of the periodic squeezing is 50%. At the maximum position where the adjusting member 222 drives the transmission member 221 to move the first plate 211 away from the second plate 212, the core material A inside the packaging bag 1 is completely uncompressed. The squeezing frequency is 5 times per minute.

[0080] The packaging bag 1 is squeezed for 10 minutes until the pressure in the packaging bag reaches a set pressure, such as 0.05 Pa. The packaging bag 1 is then compacted using the first plate 211 with a compression strain of 50%. Finally, the sealing member 3 is controlled to seal the sealing opening 1b.

[0081] The thermal conductivity of the vacuum insulation panel B finally prepared is 1.49 Mw / (m K).

[0082] In other embodiments, taking the preparation of a vacuum insulation panel B whose core material A is inorganic glass fiber as an example, the core material A is placed in a packaging bag 1 and fixed on the second plate 212, and then the transmission member 221 is driven by the adjustment member 222 to drive the first plate 211 to approach the second plate 212 along the variable pitch direction to squeeze the packaging bag 1, and the vacuum member begins to vacuum the packaging bag 1 through the seal 1b, and the compression strain is 50%.

[0083] The packaging bag 1 is squeezed for 10 minutes until the pressure inside reaches the set pressure, such as 0.05 Pa, and the pressing plate is kept compacted with a compression strain of 50%. Finally, the sealing member 3 is controlled to seal the sealing 1b.

[0084] The thermal conductivity of the vacuum insulation panel B finally prepared is 1.95 Mw / (m K).

[0085] It can be seen from the above two embodiments that periodic extrusion can make the prepared vacuum insulation panel B have a lower thermal conductivity.

[0086] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, and improvements that fall within the spirit and principles of the present application are intended to be within the scope of protection of the present application.

Claims

1. A device for preparing a vacuum insulation panel, characterized in that: include: A packaging bag, wherein the packaging bag is formed with a placement cavity for accommodating the core material; A vacuum pump, used for vacuuming the packaging bag containing the core material; An extrusion assembly is used to extrude the packaging bag containing the core material.

2. The preparation device according to claim 1, characterized in that The extrusion assembly comprises: A clamping plate assembly comprising a first plate and a second plate, wherein one of the first plate and the second plate is used to support the packaging bag, and the other of the first plate and the second plate is used to squeeze the packaging bag; The distance-changing assembly is configured to adjust the distance between the first plate and the second plate along a distance-changing direction so as to squeeze or loosen the packaging bag.

3. The preparation device according to claim 2, characterized in that The pitch-changing assembly comprises: a transmission member, wherein the first plate is disposed on the transmission member; An adjusting member is drivingly connected to the transmission member, and the transmission member is configured to be able to drive the first plate to approach or move away from the second plate along the pitch changing direction under the drive of the adjusting member.

4. The preparation device according to claim 3, characterized in that The transmission member has a plurality of installation positions along the pitch changing direction, and the first plate is detachably arranged at one of the plurality of installation positions.

5. The preparation device according to claim 2, characterized in that: There are multiple clamping plate assemblies, and the multiple clamping plate assemblies are arranged at intervals along the pitch changing direction. The pitch changing assembly is used to control the multiple clamping plate assemblies to squeeze the multiple packaging bags.

6. The preparation device according to claim 1, characterized in that The core material is an inorganic glass fiber core material.

7. The preparation device according to claim 1, characterized in that The squeezing component periodically squeezes the packaging bag.

8. The preparation device according to claim 7, characterized in that: The periodic extrusion is as follows: the number of extrusions is not less than 5 times, and the frequency of extrusion is not less than 3 times per minute.

9. The preparation device according to claim 1, characterized in that: The maximum compressive strain that the core material can withstand is not less than 30%.

10. The preparation device according to claim 1, characterized in that: The packaging bag is formed with a seal communicating with the placement cavity, and the preparation device includes a seal member, which is used to seal the seal.

11. The preparation device according to claim 10, characterized in that: The volume of the core material before being placed in the packaging bag is the initial volume, and the volume of the core material after being sealed is the compressed volume. The ratio of the initial volume to the compressed volume is not less than 2.

12. The preparation device according to claim 1, characterized in that: The packaging bag includes a heat-sealing layer.

13. The preparation device according to claim 12, characterized in that: The material of the heat sealing layer is polyethylene.

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