Ultrafiltration centrifugal inner tube and assembly method thereof

Abstract

The invention relates to the technical field of centrifugal tubes, in particular to an ultrafiltration centrifugal inner tube and an assembling method thereof. The inner pipe base body is provided with an inner cavity. The filtering membrane comprises a membrane base body, a welding part is arranged at the end part of the membrane base body, and the filtering membrane is welded on the inner wall of the inner cavity through the welding part; wherein the melting point of the membrane substrate is higher than that of the welding part. The air way design of the air suction way is used for generating vacuum suction force through negative pressure suction and fixing the filter membrane. And the welding temperature of the membrane can enable the welding part to be melted to be adhered to the inner pipe base body through heat conduction of the conduction part. According to the invention, the integrated structure of the filter membrane ensures the centrifugal strength, and can bear larger centrifugal force. The components are fewer, a plurality of components do not need to be matched and assembled, and meanwhile, the reliable filtering performance of the filtering membrane can be met. The circulation channel is designed as a welding piece heat exchange flow channel, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of centrifuge tubes, in particular to an ultrafiltration centrifuge inner tube and an assembling method thereof. Background Art

[0002] The ultrafiltration centrifuge tube consists of an inner tube and an outer tube. The inner tube holds the liquid and is placed in the centrifuge. The liquid in the inner tube is thrown out by centrifugal force and filtered through the filter membrane to achieve the purpose of interception and concentration. The outer tube is used to collect the filtered solution.

[0003] The existing production process of ultrafiltration centrifuge tubes in the industry is as follows: The first method is to pre-weld the membrane to the filter sheet and fix it by ultrasonic welding or other methods. The advantage of this method is that the tube is a whole, with extremely high strength and can withstand large centrifugal forces. Without welding, it avoids the situation where the weld breaks due to excessive centrifugal force, resulting in leakage.

[0004] The second method is to glue the membrane to the structural frame with glue, and then use a supporting structure to hold the membrane to achieve a sealing effect. The disadvantage of this method is that the centrifugal force is outward, and the membrane may have leaks under the action of centrifugal force.

[0005] The third method is to use the deformation of the rubber elastic body to press the membrane to prevent leakage. The rubber elastic body is made into a shape slightly smaller than the diaphragm. Through the cooperation of the two structures, the purpose of sealing is achieved by relying on the elastic deformation of the rubber. The disadvantage is that there are many parts and the structure is complicated, involving rubber, thus introducing a third substance. Summary of the invention

[0006] The object of the present invention is to provide an ultrafiltration centrifugal inner tube and an assembly method thereof to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An ultrafiltration centrifugal inner tube comprises an inner tube matrix and a filter membrane;

[0009] The inner tube substrate has an inner cavity;

[0010] The filter membrane comprises a membrane substrate, and a welding portion is provided at the end of the membrane substrate, and the filter membrane is welded to the inner wall of the inner cavity through the welding portion;

[0011] Wherein, the melting point of the film substrate is higher than the melting point of the welding portion.

[0012] Preferably, a conducting portion connected to the welding portion is provided at the end of the membrane substrate, and the conducting portion is not in contact with the inner wall of the inner cavity.

[0013] Preferably, the melting point of the conductive part is higher than the melting point of the welding part, and the melting point of the conductive part is lower than the melting point of the film substrate.

[0014] Preferably, the welding portion is flush with the membrane substrate or protrudes outside the membrane substrate.

[0015] Preferably, the inner wall of the inner cavity has an open flow channel, the bottom of the inner tube substrate has a guide hole connected to the bottom of the flow channel, and the filter membrane is used to cover the opening of the flow channel and the guide hole.

[0016] Preferably, the melting point of the film substrate is between 160°C and 220°C, the melting point of the conduction portion is between 160°C and 190°C, the melting point of the welding portion is between 150°C and 180°C, and the welding temperature of the welding sheet is between 150°C and 190°C.

[0017] To achieve the above object, the present invention also provides the following technical solutions:

[0018] A method for assembling an ultrafiltration centrifuge inner tube as described in any one of the above, comprising:

[0019] The conducting part is attached to the welding sheet, and the vacuum chamber is evacuated through the air evacuation channel to keep the vacuum chamber in a vacuum state, so that the filter membrane is adsorbed and fixed on the welding sheet;

[0020] The welding piece is heated, and the welding part is melted by heat conduction through the conducting part;

[0021] Extend the welding sheet and the filter membrane adsorbed and fixed on the welding sheet into the inner cavity together, so that the welding part is adhered to the inner wall of the inner cavity and covers the opening and the guide hole of the flow channel;

[0022] The vacuuming of the vacuum chamber is removed, and the vacuum chamber is restored from a vacuum state to a normal pressure state, so that the welding sheet is separated from the filter membrane and withdrawn from the inner cavity, thereby completing the welding of the filter membrane and the inner tube substrate.

[0023] Preferably, the conducting part protrudes out of the film substrate, so that a vacuum chamber is formed between the conducting part, the film substrate and the welding sheet;

[0024] An exhaust passage for connecting to the negative pressure device and communicating with the vacuum chamber is reserved on the welding sheet.

[0025] Preferably, the welding plate has a circulation channel for circulating condensed water for cooling, and the circulation channel is not connected to the exhaust duct.

[0026] Preferably, the welding sheet is made of metal.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention: The welding sheet is made of pure copper to ensure good thermal conductivity and certain strength. The airway design of the air duct is used to generate vacuum suction by pumping negative pressure to fix the filter membrane. The welding sheet is used as a heating unit for overall heating. The welding temperature of the membrane can be used for heat conduction through the conduction part to melt the welding part, and the welding sheet will not be stuck together (in a "semi-molten" state).

[0029] The present invention applies a certain pressure to the filter membrane through the negative pressure of the air duct so that the membrane can be firmly adsorbed on the welding sheet during welding. The circulation channel is connected to condensed water to quickly cool the welding sheet and facilitate the welding of the next membrane sheet. The advantages are: the filter membrane is a plastic component as a whole, the original structure is not destroyed, and welding is performed in a narrow inner cavity space. The design of the water cooling structure ensures the efficiency of welding, and the temperature can be quickly reduced for welding the next membrane.

[0030] The present invention: The structure of the filter membrane integrally formed ensures centrifugal strength and can withstand greater centrifugal force. There are fewer parts, and multiple parts do not need to be assembled together, while the filter membrane can meet the reliable filtering performance. The circulation channel is designed as a heat exchange flow channel for the welding plate, which improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0032] Figure 1 It is a schematic diagram of the structure of the present invention.

[0033] Figure 2 For the present invention Figure 1 Cross-section view at AA in the middle.

[0034] Figure 3 This is a schematic diagram of the filter membrane of the present invention not being welded to the inner wall of the inner cavity.

[0035] Figure 4 It is a front view of the filter membrane of the present invention.

[0036] Figure 5 This is a rear view of the filter membrane of the present invention.

[0037] Figure 6 This is a schematic diagram of the filter membrane and the conductive part of the present invention being attached to the welding sheet.

[0038] Figure 7 It is a schematic diagram of the structure in which the bottom end of the inner tube is inserted into the outer tube of the present invention.

[0039] In the figure: 1-inner tube substrate, 2-inner cavity, 3-filter membrane, 4-flow guide hole, 5-flow channel, 6-opening, 7-membrane substrate, 8-conduction part, 9-welding part, 10-welding sheet, 11-vacuum chamber, 12-exhaust channel, 13-outer tube, 14-plug cover. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0043] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0044] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0045] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0046] See also Figures 1 to 7 , the present invention provides a technical solution:

[0047] An ultrafiltration centrifuge inner tube is inserted into an outer tube 13, and can be used in conjunction with the outer tube 1 to form an ultrafiltration centrifuge tube. The ultrafiltration centrifuge tube can be used in a centrifuge. The ultrafiltration centrifuge tube can be used to separate biological substances such as antibody enzymes, nucleic acids and proteins for the purposes of concentration, desalination, purification and fractionation, such as concentrated urine, serum, plasma and cerebrospinal fluid and other concentrated substances (hereinafter specifically described as concentrated liquids) are separated and collected. After the inner tube is inserted into the outer tube 13, a plug cover 13 connected to the opening at the top of the outer tube 1 covers the outer tube 14, thereby achieving sealing of the ultrafiltration centrifuge tube.

[0048] The following is a detailed introduction:

[0049] An ultrafiltration centrifugal inner tube, comprising an inner tube matrix 1 and a filter membrane 3;

[0050] The inner tube substrate 1 has an inner cavity 2;

[0051] The filter membrane 3 includes a membrane substrate 7, and a welding portion 9 is provided at the end of the membrane substrate 7. The filter membrane 3 is welded to the inner wall of the inner cavity 2 through the welding portion 9.

[0052] The melting point of the film substrate 7 is higher than the melting point of the welding portion 9 .

[0053] In a specific embodiment, if Figure 6 As shown, at the end of the membrane substrate 7 there is a conductive portion 8 connected to a welding portion 9, and the conductive portion 8 does not contact the inner wall of the inner cavity 2. The melting point of the conductive portion 8 is higher than the melting point of the welding portion 9, and the melting point of the conductive portion 8 is lower than the melting point of the membrane substrate 7. The welding portion 9 is flush with the membrane substrate 7 or protrudes outside the membrane substrate 7.

[0054] In a specific embodiment, if Figure 2 and Figure 3 As shown, the inner wall of the inner cavity 2 has a flow channel 5 with an opening 6, the bottom of the inner tube substrate 1 has a guide hole 4 connected to the bottom of the flow channel 5, and the filter membrane 3 is used to cover the opening 6 of the flow channel 5 and the guide hole 4.

[0055] In a specific embodiment, the melting point of the film substrate 7 is between 160°C and 220°C, the melting point of the conductive portion 8 is between 160°C and 190°C, the melting point of the welding portion 9 is between 150°C and 180°C, and the welding temperature of the welding sheet 10 is between 150°C and 190°C.

[0056] The present invention can be applied to an assembly method of an ultrafiltration centrifugal inner tube, the method comprising:

[0057] The conducting part 8 is attached to the welding sheet 10, and the vacuum chamber 11 is evacuated with negative pressure through the exhaust passage 12, so that the vacuum chamber 11 is kept in a vacuum state, so that the filter membrane 3 is adsorbed and fixed on the welding sheet 10; when the vacuum chamber 11 is kept in a vacuum state, the vacuum pressure in the vacuum chamber 11 can be flexibly set according to actual conditions, as long as the filter membrane 3 can be well adsorbed and fixed on the welding sheet 10;

[0058] The welding sheet 10 is heated, and the welding portion 9 is melted by heat conduction through the conducting portion 8;

[0059] The welding sheet 10 and the filter membrane 3 adsorbed and fixed on the welding sheet 10 are inserted into the inner cavity 2 together, so that the welding portion 9 is adhered to the inner wall of the inner cavity 2 and covers the opening 6 of the flow channel 5 and the guide hole 4;

[0060] The vacuum chamber 11 is de-aired and restored from a vacuum state to a normal pressure state, so that the welding sheet 10 is separated from the filter membrane 3 and withdrawn from the inner cavity 2, thereby completing the welding of the filter membrane 3 and the inner tube substrate 1.

[0061] In a specific embodiment, if Figure 6 As shown, the conduction part 8 protrudes out of the membrane substrate 7, so that the conduction part 8, the membrane substrate 7 and the welding sheet 10 form a vacuum chamber 11; an air extraction channel 12 is reserved on the welding sheet 10 for accessing the negative pressure device and communicating with the vacuum chamber 11. The welding sheet 10 has a circulation channel (not shown in the figure) for circulating and cooling condensed water, and the circulation channel is independent of the air extraction channel 12 and is not connected. The circulation channel has two interfaces, one for the liquid inlet and the other for the liquid outlet.

[0062] The vacuuming method is as follows: the conducting part 8 protrudes outwards so that a vacuum chamber 11 is formed between the conducting part 8 , the membrane substrate 7 and the welding sheet 10 , and an exhaust passage 12 is reserved on the welding sheet 10 for accessing a negative pressure device and communicating with the vacuum chamber 11 .

[0063] In a specific embodiment, the welding sheet 10 is made of metal. The membrane substrate 7 can be made of PES, the conducting part 8 can be made of ABC, and the welding part 9 can be made of plastic.

[0064] In the present invention, the filter membrane 3 and the conductive part 8 are attached to the welding sheet 10 , and the negative pressure device / vacuum device is connected to the exhaust duct 12 , so that the vacuum chamber 10 can be negatively pressurized, so that the filter membrane 3 is adsorbed and fixed on the welding sheet 10 .

[0065] When the welding sheet 10 is heated to the required welding temperature between 150 and 160°C, the heat conduction of the conducting part 8 can heat the welding part 9, and the welding part 9 is melted, but the conducting part 8 (which is in a "semi-molten" state, which can also be said to be a softened state relative to the melting of the welding part 9, and will not become a sticky / viscoelastic state or a sticky / viscofluid state) is not adhered to the welding sheet 10. Considering that after the welding part 9 (and the membrane substrate 7) are welded to the inner wall of the inner tube substrate 1 (i.e., the inner wall of the inner cavity 2), the welding sheet 10 needs to be separated from the filter membrane 3, so the melting point of the membrane substrate 7 needs to be higher than the melting point of the conducting part 8. The melting point of the conduction part 8 is higher than that of the welding part 9, so that when welding through the welding sheet 10, the conduction part 8 is in a semi-molten state, ensuring that it is adsorbed and fixed on the welding sheet 10 after vacuuming, and will not stick to the welding sheet 10, so that it is easy to separate from the filter membrane 3 after cooling, and the welding part 9 is melted by heat conduction through the conduction part 8. After the welding part 9 is melted, it is firmly adhered to the inner wall of the inner cavity 2, so that the membrane matrix 7 can be firmly welded to the inner wall of the inner cavity 2, and during the welding process, the welding temperature will not affect the membrane matrix 7, thereby ensuring the integrity of the filter membrane 3 and the reliability of filtration.

[0066] The welding sheet 10 is heated to 150° C. to 190° C., and the filter membrane 3 is adhered and fixed to the inner wall of the inner cavity 2 through the welding portion 8 .

[0067] The welding sheet 10 and the filter membrane 3 are fixed by adsorption by connecting the negative pressure device / vacuum device to the exhaust duct 12, so that the vacuum chamber 10 can be negatively pressurized, so that the welding sheet 10 and the filter membrane 3 are more firmly attached.

[0068] After the filter membrane 3 is adsorbed and fixed on the welding sheet 10, the welding sheet 10 and the filter membrane 3 are extended into the inner cavity 2, and the filter membrane 3 is close to the inner wall of the inner cavity 2 (inner tube substrate 1). Because the melting point of the welding part 9 of the filter membrane 3 is lower, the welding part 9 of the filter membrane 3 is melted and bonded to the inner wall to complete the welding. After welding, the welding sheet 10 is cooled by condensed water and separated from the filter membrane 3.

[0069] In the present invention, the conducting part 5 is the outer side of the filter membrane and protrudes outward a little (of course, the welding part 9 is the inner side of the filter membrane and can also protrude outward a little), that is, Figure 6 As shown, it protrudes a little to the right of the membrane substrate 7, so that negative pressure can be achieved during vacuuming to facilitate adsorption. Therefore, after the welding is completed, the negative pressure is released and the welding sheet 10 can be withdrawn. The cold water cooling can avoid the risk of flaw detection caused by the welding sheet, thereby achieving the purpose of increasing work efficiency.

[0070] After the filter membrane 3 is welded to the inner wall of the inner cavity 2, the filter membrane 3 covers the opening 6 of the flow channel 5, and the sample (or sample liquid) enters the inner cavity 2 from the sampling opening of the inner tube 2 and is filtered through the filter membrane 3 to form a filtrate. The filtrate can enter the flow channel 5 from the opening 6 and be discharged from the guide hole 4 at the bottom, and the unfiltered sample liquid is collected.

[0071] In general, the present invention: the welding sheet 10 is made of metal material as a whole, which ensures good thermal conductivity and has a certain strength. In a specific embodiment, the welding sheet 10 is made of pure copper. The air duct design of the exhaust duct 12 is used to extract negative pressure to generate vacuum suction and fix the filter membrane 3 diaphragm. The welding sheet 10 is used as a heating unit for overall heating, and the diaphragm welding temperature is between 150°C and 190°C. Through the negative pressure of the exhaust duct 12, a certain pressure is applied to the filter membrane 3 so that the membrane can be firmly adsorbed on the welding sheet 10 during welding. The circulation channel is connected to condensed water to quickly cool down the welding sheet 10 and facilitate the welding of the next diaphragm. The advantage is that the filter membrane 3 is a plastic component as a whole, does not destroy the original structure, is welded in the narrow inner cavity 2 space, and the design of the water cooling structure ensures the efficiency of welding, and can quickly cool down for the welding of the next membrane.

[0072] In the present invention, the integrally formed structure of the filter membrane 3 ensures centrifugal strength and can withstand greater centrifugal force. There are fewer parts, and multiple parts do not need to be assembled together, while the reliable filtering performance of the filter membrane can be met. The circulation channel is designed as a heat exchange flow channel for the welding plate 10, which improves production efficiency.

[0073] The present invention welds the filter membrane 3 to the inner wall of the inner tube substrate 1, which has better sealing performance and can reduce the risk of leakage compared with the prior art that uses glue to stick the membrane to the tube wall. Compared with the prior art that relies on the elastic deformation of rubber to achieve the purpose of membrane sealing, the structure is more streamlined and can eliminate the risk of unnecessary substances being introduced into the filter membrane and the ultrafiltration centrifugal inner tube.

[0074] The present invention, the undescribed parts are prior art.

[0075] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An ultrafiltration centrifugal inner tube, characterized in that: It comprises an inner tube substrate (1) and a filter membrane (3); The inner tube substrate (1) has an inner cavity (2); The filter membrane (3) comprises a membrane substrate (7), and a welding portion (9) is provided at the end of the membrane substrate (7), and the filter membrane (3) is welded to the inner wall of the inner cavity (2) via the welding portion (9); Wherein, the melting point of the film substrate (7) is higher than the melting point of the welding portion (9).

2. The ultrafiltration centrifuge inner tube according to claim 1, characterized in that: A conducting portion (8) connected to a welding portion (9) is provided at the end of the membrane substrate (7), and the conducting portion (8) is not in contact with the inner wall of the inner cavity (2).

3. The ultrafiltration centrifugal inner tube according to claim 2, characterized in that: The melting point of the conductive part (8) is higher than the melting point of the welding part (9), and the melting point of the conductive part (8) is lower than the melting point of the film substrate (7).

4. An ultrafiltration centrifuge inner tube according to any one of claims 2 or 3, characterized in that: The welding portion (9) is flush with the membrane substrate (7) or protrudes outside the membrane substrate (7).

5. The ultrafiltration centrifuge inner tube according to claim 1, characterized in that: The inner wall of the inner cavity (2) has a flow channel (5) with an opening (6), the bottom of the inner tube base (1) has a flow guide hole (4) connected to the bottom of the flow channel (5), and the filter membrane (3) is used to cover the opening (6) of the flow channel (5) and the flow guide hole (4).

6. The ultrafiltration centrifuge inner tube according to claim 1, characterized in that: The melting point of the film substrate (7) is between 160°C and 220°C, the melting point of the conduction part (8) is between 160°C and 190°C, the melting point of the welding part (9) is between 150°C and 180°C, and the welding temperature of the welding sheet (10) is between 150°C and 190°C.

7. A method for assembling an ultrafiltration centrifuge inner tube according to any one of claims 1 to 6, characterized in that: include: The conducting part (8) is attached to the welding sheet (10), and the vacuum chamber (11) is evacuated through the air evacuation passage (12) so that the vacuum chamber (11) is kept in a vacuum state, so that the filter membrane (3) is adsorbed and fixed on the welding sheet (10); The welding sheet (10) is heated, and the welding portion (9) is melted by heat conduction from the conduction portion (8); The welding sheet (10) and the filter membrane (3) adsorbed and fixed on the welding sheet (10) are inserted into the inner cavity (2) together, so that the welding portion (9) is adhered to the inner wall of the inner cavity (2) and covers the opening (6) of the flow channel (5) and the guide hole (4); The vacuum chamber (11) is de-aired and the vacuum chamber (11) is restored from a vacuum state to a normal pressure state, so that the welding sheet (10) is separated from the filter membrane (3) and withdrawn from the inner cavity (2), thereby completing the welding of the filter membrane (3) and the inner tube substrate (1).

8. The method for assembling an ultrafiltration centrifuge inner tube according to claim 7, characterized in that: The conducting portion (8) protrudes out of the membrane substrate (7), so that a vacuum chamber (11) is formed between the conducting portion (8), the membrane substrate (7) and the welding sheet (10); An air extraction passage (12) is reserved on the welding sheet (10) for connecting to a negative pressure device and communicating with the vacuum extraction chamber (11).

9. The method for assembling an ultrafiltration centrifuge inner tube according to claim 8, characterized in that: The welding plate (10) has a circulation channel for circulating and cooling condensed water, and the circulation channel is not connected to the exhaust duct (12).

10. The method for assembling an ultrafiltration centrifuge inner tube according to claim 7, characterized in that: The welding sheet (10) is made of metal.

Images