A welding assembly and welding method for the shell of a medical CT metal tube

Abstract

The present invention discloses a welding assembly and a welding method for a medical CT metal tube housing. The welding assembly includes: a base, a tooling protection side plate fixed on the base for limiting the CT metal tube housing, and an upper fixing seat and a lower fixing seat fixed on the base for assembling the CT metal tube housing; the welding method includes: S1, assembling the fitting to be welded; S2, vacuum welding; S3, furnace out and leak detection; S4, welding the window area; the welding assembly of the present invention can be positioned and assembled to facilitate integral welding, and the welding method can avoid the non-uniform internal structure of the material to be welded caused by uneven furnace temperature, thereby resulting in deformation, and at the same time solve the problems of bumping and scratching caused by shape correction, effectively shortening the production and processing cycle of the assembly and improving production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and particularly to a welding assembly and a welding method for a medical CT metal tube housing of a metal tube. Background Art

[0002] The CT tube is the core component of a CT (Computed Tomography) scanner, which includes an X-ray tube for generating X-rays. The main function of the CT tube is to generate high-energy X-ray beams. These X-ray beams pass through the patient's body, are captured by detectors, and then processed by a computer to generate cross-sectional images. The structure of the CT tube generally includes an X-ray tube, a vacuum chamber, insulating oil, and a tube housing. The X-ray tube includes a cathode (generating an electron beam) and an anode (receiving the electron beam and generating X-rays). The vacuum chamber is a sealed vacuum environment where the electron beam moves from the cathode to the anode. The insulating oil is used for cooling and insulation, and is filled between the outer shell of the vacuum chamber and the outer shell of the tube. The tube housing is the outer shell for protecting the X-ray tube, usually made of metal. The internal structure of the CT tube is complex, with many types of parts, involving many disciplines. The selection of materials is crucial. Many components are used in a vacuum environment, and the materials should not release gas at high temperatures to ensure the service life of the tube.

[0003] In the prior art, after the tube housing parts of the CT tube are processed, multiple assembly weldings with graded temperature steps are required. Multiple weldings may cause deformation of the metal parts during welding, which will cause trouble for each welding assembly. Deformation may lead to problems such as inapplicability of the final assembly. Using a deformed tube housing may cause problems such as a decrease in CT image quality, damage to internal components of the tube, an increase in maintenance costs, and safety issues. Summary of the Invention

[0004] To solve the above problems, the present invention provides a welding assembly and a welding method for a medical CT metal tube housing.

[0005] A welding assembly for a medical CT metal tube housing; includes a base, a tooling protection side plate fixed on the base for limiting the medical CT metal tube housing, and an upper fixing seat and a lower fixing seat fixed on the base for assembling the medical CT metal tube housing. The upper fixing seat and the lower fixing seat are clamped by a clamp. The lower fixing seat is clamped to the base, and a beryllium window welding movable pressing block is provided on the upper fixing seat.

[0006] A welding method for a medical CT metal tube housing includes the following steps:

[0007] S1. Assemble the parts to be welded;

[0008] Clean each component of the CT metal tube housing. The components of the CT metal tube housing include a stainless steel ring, a tube housing, a kovar ring, a grounding block, and a beryllium window. First, fit and install the stainless steel ring with a tooling part for fixing each component. Then, fit and install the stainless steel ring with the tube housing. Next, place the kovar ring at the port or connection of the tube housing for assembly installation. Subsequently, place the beryllium window on the tube housing and use the tooling part for fastening and fixing. Then, assemble the heat dissipation strips and the grounding block to obtain an assembly to be welded.

[0009] S2. Vacuum welding;

[0010] First, preheat the vacuum furnace to a temperature of 800 - 900 °C in the vacuum furnace, then cool the vacuum furnace to 400 - 500 °C. Subsequently, place the assembly to be welded into the vacuum furnace. The pressure in the vacuum furnace is less than or equal to 6.5×10 -3 Pa, and heat it up at a rate of 5 - 7 °C / min to T - 20 - T - 10 °C for welding. The welding time is 0.1 - 5 min to obtain the tooling part. Here, T is the melting point of the tube housing.

[0011] S3. Furnace out and leak detection;

[0012] After welding is completed, lower the temperature in the vacuum furnace to 100 - 200 °C, then take out the tooling part and each component for a first leak detection. If there is a component that fails the first leak detection, clean the component that fails the first leak detection and repeat step S2 until it passes the first leak detection and then proceed to the next step.

[0013] S4. Weld the window area;

[0014] First, heat up the vacuum furnace to 400 - 500 °C, rotate the tooling part by 90°, and when heating up to a temperature of T - 20 - T - 10 °C and the welding time is 0.1 - 3 min, weld the window area. Then, conduct a second leak detection. If there is a component that fails the second leak detection, clean the component that fails the second leak detection and repeat welding the window area until it is qualified, then complete the welding.

[0015] Description: By welding through the above method, the thermal deformation of the shell parts at high temperature can be reduced, problems such as knocking and scratching caused by shape correction can be avoided, the production and processing cycle of the components can be effectively shortened, and the production efficiency can be improved; the qualified rate of the welded tube shell components by this process is also high, the parts have small deformation, the influence of the shell deformation on subsequent processing is prevented, the finished components do not need to be shape-corrected after the second welding of the window, and each component can also be positioned and assembled to facilitate integral welding. By adjusting the temperature of the vacuum furnace and preheating, the uneven internal structure of the material to be welded caused by uneven furnace temperature and thus the resulting deformation can be avoided. Through the cleaning step, residues such as welding slag generated by welding can be cleaned to avoid affecting the quality of the welded joint.

[0016] Further, the material of the tube shell is oxygen-free copper.

[0017] Description: Since oxygen-free copper has good electrical conductivity and heat dissipation performance, it can ensure that the X-rays generated during the operation of the CT tube have sufficient intensity and stability, which helps to improve the clarity and accuracy of CT images.

[0018] Further, the welding adopts vacuum brazing.

[0019] Description: Vacuum brazing can ensure high-quality welds of materials, avoid material deformation, reduce material loss, improve production efficiency, have wide applicability, and good cleanliness and strength, etc.

[0020] Further, the first leak detection adopts the soap solution method, and the second leak detection adopts the ultrasonic method or the gas detection method.

[0021] Further, in step S1, the cleaning is completed by the first cleaning agent, and S3 and S4 are completed by the second cleaning agent. The first cleaning agent includes alkyl glycoside, ethylene glycol monobutyl ether, and glutamic acid tetraacetic acid with a mass ratio of 1:3 - 5:2, and the second cleaning agent includes citric acid, castor oil derivative, borate, and ethylenediaminetetraacetic acid with a mass ratio of 5 - 7:5:2 - 3:2.

[0022] Description: By cleaning with two different cleaning agents before and after welding, the surface of the materials corresponding to each step can be treated specifically to ensure high-quality welding; before welding, the main contaminants on the material surface are the oxide layer and grease layer, etc. The combination of alkyl glycoside, ethylene glycol monobutyl ether, and glutamic acid tetraacetic acid can remove these contaminants without damaging the metal surface and has good cleaning effect. After welding, the second cleaning agent with the above components can achieve efficient cleaning.

[0023] Further, the preparation method of the second cleaning agent is as follows: First, add the castor oil derivative to citric acid and mix and stir for 5 - 8 min; the stirring speed is 500 - 600 r / min. Then, add borate and ethylenediaminetetraacetic acid in sequence and stir for 10 - 20 min; obtain a mixture, and use a pH regulator to adjust the pH of the mixture to 7 to obtain the second cleaning agent.

[0024] Note: The second cleaning agent prepared by the above method can achieve efficient cleaning, and at the same time, a protective film is formed on the metal surface after cleaning to prevent it from being further oxidized and corroded.

[0025] Further, in S1, there are gaps between the components of the CT metal tube housing, and the gap value of the gaps is determined by the coefficient of thermal expansion of the material and the structure.

[0026] Note: Since the CT metal tube housing belongs to a thin-walled component, the thin-walled component will expand at high temperatures, and the thermal deformation coefficients of each component are different. It is necessary to consider different coefficients of thermal expansion of materials and structures to determine the gap after assembly.

[0027] Further, the gap value is calculated by the following formula:

[0028] ;

[0029] In the formula, is the gap value, is the length of the gap contact surface, is the average value of the coefficients of thermal expansion of the two materials on the gap contact surface, K is the difference between the thermal conductivity of the tube housing and the thermal conductivity of the heat dissipation strip, P is the thermal power during the operation of the CT metal tube, A is the area of the heat dissipation strip, and t is the total welding time.

[0030] Note: In the prior art, the size of the gap to be reserved for welding is usually determined by experience. Judging solely by experience may lead to the welding not achieving the ideal effect, such as slight deformation at the welding point and air leakage after welding. Therefore, calculating the appropriate gap is very important for the welding of the CT metal tube housing. Through the above formula, the calculated gap value is relatively practical, and the yield of the welded product is relatively high, and the deformation rate is relatively small.

[0031] Further, the heat dissipation strip is a wavy heat dissipation strip.

[0032] Note: The wavy heat dissipation strip has a higher heat dissipation efficiency and can make the temperature in the welding high-temperature furnace more uniform, reducing the uneven heating between components, and is suitable for the welding process of the present invention.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: The welding method of the present invention can reduce the thermal deformation of the housing parts at high temperatures, avoid problems such as knocking and scratching caused by shape correction, effectively shorten the production and processing cycle of the components, and improve production efficiency; The qualified rate of the welded tube shell components by this process is also high, the parts have small deformation, preventing the influence of the housing deformation on subsequent processing. After the second welding of the finished components at the window, shape correction is not required. Moreover, the components can be positioned and assembled to facilitate integral welding. By adjusting the temperature and preheating of the vacuum furnace, it is possible to avoid uneven internal structure of the materials to be welded caused by uneven furnace temperature, thereby avoiding deformation. Through the cleaning step, residues such as welding slag generated by welding can be cleaned to avoid affecting the quality of the welded joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic external view of the welded component assembly of Embodiment 1 of the present invention;

[0035] Figure 2 is a left view of the welded component assembly of Embodiment 1 of the present invention;

[0036] Figure 3 is a front view of the welded component assembly of Embodiment 1 of the present invention;

[0037] Figure 4 is a bottom view of the welded component assembly of Embodiment 1 of the present invention.

[0038] Wherein, 1 - base, 2 - CT metal tube housing, 3 - tooling protection side plate, 4 - upper fixing seat, 5 - lower fixing seat, 6 - beryllium window welding movable pressing block. DETAILED DESCRIPTION OF THE INVENTION

[0039] To further elaborate on the methods and achieved effects of the present invention, the technical solutions of the present invention will be clearly and completely described below in combination with experiments.

[0040] An embodiment of the present invention provides a welding component and a welding method for a medical CT metal tube housing. By assembling the fittings, after assembling each part, integral welding is performed. Through the welding method and parameter setting, the effect of integral welding can be optimized, and deformation during the welding of the CT metal tube housing can be avoided.

[0041] In the prior art, some argon arc welding areas after component welding still need to be welded by argon arc with parts that match the assembly. If the welded area is deformed and affects the assembly, it will cause the parts to be unable to be assembled. At the same time, the geometric tolerance requirements of each area of the component also need to be considered. If the geometric tolerance exceeds the standard seriously, it will cause the X-ray imaging to deviate from the preset trajectory. Since the welding is carried out in a vacuum furnace, the welding temperature is generally about 1000 °C, and the temperature is still 700 °C until the last welding. Metal parts will be deformed after high-temperature welding, which will cause trouble for each welding assembly, and the deformation will lead to final assembly problems. Therefore, a new welding method is needed, which should not only ensure that the welding does not deform, but also consider better welding effects.

[0042] Example 1: As Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 shown, a welding assembly for a medical CT metal tube housing includes a base 1, a tooling protection side plate 3 fixed on the base 1 for limiting the medical CT metal tube housing 2, and an upper fixing seat 4 and a lower fixing seat 5 fixed on the base 1 for assembling the medical CT metal tube housing 2. The upper fixing seat 4 and the lower fixing seat 5 are clamped by a clamp, the lower fixing seat 5 is clamped with the base 1, and a beryllium window welding movable pressing block 6 is provided on the upper fixing seat 4;

[0043] A welding method for a medical CT metal tube housing, based on the above welding assembly, includes the following steps:

[0044] S1. Assemble the parts to be welded;

[0045] Clean each component of the medical CT metal tube housing 2. The components of the medical CT metal tube housing 2 include a stainless steel ring part, a tube housing, a kovar ring, a grounding block, and a beryllium window. First, fit and install the stainless steel ring part with the welding assembly for fixing each component, then fit and install the stainless steel ring part with the tube housing, then place the kovar ring at the port or connection of the tube housing for assembly and installation, and then place the beryllium window under the beryllium window welding movable pressing block 6 and use the welding assembly for fastening and fixing; then assemble the heat dissipation strip and the grounding block to obtain the parts to be welded; the material of the tube housing is oxygen-free copper; the welding uses vacuum brazing; the heat dissipation strip is a wavy heat dissipation strip;

[0046] Among them, the above cleaning is completed by a first cleaning agent, and the raw materials of the first cleaning agent include alkyl polyglycoside, ethylene glycol monobutyl ether, and glutamic acid tetraacetic acid with a mass ratio of 1:4:2;

[0047] Among them, there are gaps between the components of the medical CT metal tube housing 2, and the gap value is determined by the coefficient of thermal expansion of the material and the structure;

[0048] Specifically, the gap value is calculated by the following formula;

[0049] ;

[0050] In the formula, is the gap value, is the length of the gap contact surface, is the average value of the thermal expansion coefficients of the two materials on the gap contact surface, K is the difference between the thermal conductivity of the tube shell and the thermal conductivity of the heat dissipation strip, P is the thermal power during the operation of the CT metal tube, A is the area of the heat dissipation strip, and t is the total welding time; after calculation, a gap of 0.75 mm is left;

[0051] S2. Vacuum welding;

[0052] First, preheat the vacuum furnace to a temperature of 850 °C in the vacuum furnace, then cool the vacuum furnace to 450 °C, and then put the assembly to be welded into the vacuum furnace. The pressure in the vacuum furnace is less than or equal to 6.5×10 -3 Pa, and when the temperature is raised to T - 15 °C at a rate of 6 °C / min, welding is carried out, and the welding time is 0.1 - 5 min to obtain a tooling part; where T is the melting point of the tube shell, which is 1080 °C;

[0053] S3. Furnace out leak detection;

[0054] After welding is completed, lower the temperature in the vacuum furnace to 150 °C, then take out the tooling part and each component and conduct a primary leak detection. If there is a component that fails the primary leak detection, clean the component that fails the primary leak detection and repeat step S2 until the primary leak detection is qualified and then proceed to the next step. The primary leak detection uses the soap solution method:

[0055] S4. Weld the window area;

[0056] First, raise the temperature of the vacuum furnace to 450 °C, rotate the tooling part by 90°, and when the temperature is raised to T - 20 ~ T - 10 °C and the welding time is 1 min, weld the window area, and then conduct a secondary leak detection. If there is a component that fails the secondary leak detection, clean the component that fails the secondary leak detection and repeat welding the window area; until it is qualified, the welding is completed. The secondary leak detection uses the ultrasonic method or the gas detection method;

[0057] Among them, the cleaning in S3 and S4 is completed using a second cleaning agent. The raw materials of the second cleaning agent include citric acid, castor oil derivative, borate, and ethylenediaminetetraacetic acid with a mass ratio of 6:5:2.5:2;

[0058] The preparation method of the second cleaning agent is as follows: First, add the castor oil derivative to citric acid and mix and stir for 6 min; the stirring speed is 550 r / min. Then, add borate and ethylenediaminetetraacetic acid in sequence and stir for 15 min; obtain a mixture, and use a pH regulator to adjust the pH of the mixture to 7 to obtain the second cleaning agent.

[0059] Example 2: The difference between this example and Example 1 lies in the different temperature parameters of vacuum welding. In S2, first preheat the vacuum furnace until the temperature inside the vacuum furnace reaches 800 °C, then cool the vacuum furnace to 400 °C, and then put the fitting to be welded into the vacuum furnace. The pressure in the vacuum furnace is less than or equal to 6.5×10 -3 Pa, and when heating up at a speed of 5 °C / min to T - 20 °C, the welding time is 0.1 min; where T is the melting point of the tube shell, which is 1080 °C.

[0060] Example 3: The difference between this example and Example 1 lies in the different temperature parameters of vacuum welding. In S2, first preheat the vacuum furnace until the temperature inside the vacuum furnace reaches 900 °C, then cool the vacuum furnace to 500 °C, and then put the fitting to be welded into the vacuum furnace. The pressure in the vacuum furnace is less than or equal to 6.5×10 -3 Pa, and when heating up at a speed of 7 °C / min to T - 10 °C, the welding time is 5 min; where T is the melting point of the tube shell, which is 1080 °C.

[0061] Example 4: The difference between this example and Example 1 lies in the different temperature parameters of leak detection treatment. In S3, lower the temperature inside the vacuum furnace to 100 °C.

[0062] Example 5: The difference between this example and Example 1 lies in the different temperature parameters of leak detection treatment. In S3, lower the temperature inside the vacuum furnace to 200 °C.

[0063] Example 6: The difference between this example and Example 1 lies in the different temperature parameters of the welding window area. In S4, first heat up the vacuum furnace to 400 °C, rotate the tooling part by 90°, and then heat up to the temperature of T - 20 °C with a welding time of 0.1 min.

[0064] Example 7: The difference between this example and Example 1 lies in the different temperature parameters of the welding window area. In S4, first heat up the vacuum furnace to 500 °C, rotate the tooling part by 90°, and then heat up to the temperature of T - 10 °C with a welding time of 3 min.

[0065] Example 8: The difference between this example and Example 1 lies in that the first cleaning agent includes alkyl polyglycoside, ethylene glycol monobutyl ether, and glutamic acid tetraacetic acid with a mass ratio of 1:3:2.

[0066] Example 9: The difference between this example and Example 1 is that the first cleaning agent comprises alkyl polyglycoside, ethylene glycol monobutyl ether and glutamic acid tetraacetic acid with a mass ratio of 1:5:2.

[0067] Example 10: The difference between this example and Example 1 is that the second cleaning agent comprises citric acid, castor oil derivative, borate and ethylenediaminetetraacetic acid with a mass ratio of 5:5:3:2.

[0068] Example 11: The difference between this example and Example 1 is that the second cleaning agent comprises citric acid, castor oil derivative, borate and ethylenediaminetetraacetic acid with a mass ratio of 7:5:2:2.

[0069] Example 12: The difference between this example and Example 1 is that the preparation method of the second cleaning agent is as follows: First, add the castor oil derivative to citric acid and mix and stir for 5 min; the stirring speed is 500 r / min. Then, add borate and ethylenediaminetetraacetic acid in sequence and stir for 10 min; a mixture is obtained, and the pH of the mixture is adjusted to 7 using a pH regulator.

[0070] Example 13: The difference between this example and Example 1 is that the preparation method of the second cleaning agent is as follows: First, add the castor oil derivative to citric acid and mix and stir for 8 min; the stirring speed is 600 r / min. Then, add borate and ethylenediaminetetraacetic acid in sequence and stir for 20 min; a mixture is obtained, and the pH of the mixture is adjusted to 7 using a pH regulator.

[0071] Experimental Example: This experimental example is based on the recording scheme in Example 1, aiming to clarify the actual application effect of the present invention.

[0072] Experimental Example: I. Observe the CT metal tube housing after welding in Examples 1 to 13 respectively, and no observable deformation occurs.

[0073] 1. Explore the influence of different parameters on the performance of the CT metal tube housing.

[0074] Comparative Example 1: The difference from Example 1 is that the welding and assembly of the CT metal tube housing adopts the method of block counterweight, the welding stability is very poor, the housing is severely deformed at high temperature, and there will be a phenomenon of incomplete welding in the welding area.

[0075] Comparative Example 2: The difference from Example 1 is that in S2, vacuum welding is carried out; instead of preheating the vacuum furnace to 850 °C and cooling to 450 °C in the vacuum furnace, it is directly heated at a rate of 6 °C / min and welded at the temperature of Example 1.

[0076] Comparative Example 3: Different from Example 1, in S4, instead of heating the vacuum furnace to 450°C, it is directly heated and welded.

[0077] Comparative Example 4: Different from Example 1, in S1, S3, and S4, ethanol is used for cleaning;

[0078] Comparative Example 5: Different from Example 1, there is no gap reserved between components;

[0079] Take Example 1 and Comparative Examples 1 - 5 for comparison, as shown in Table 1;

[0080] Table 1 Experimental results of the welded CT metal tube housing obtained by different welding methods

[0081]

[0082] As can be seen from Table 1, by comparing Example 1 with Comparative Example 1, it can be seen that after welding using the method in Example 1, the deformation amount is very small and can be ignored. In Comparative Example 1, the deformation amount caused during the welding process is relatively large. The reason may be that the existing technology does not use an integrated welding method, and the temperature, pressure, etc. of the front and back welding are different, resulting in deformation of several welds, making it difficult to use the welded part as a finished product and having a low finished product efficiency;

[0083] By comparing Example 1 with Comparative Example 2 and Comparative Example 3, it can be found that in Comparative Example 2, the vacuum furnace was not preheated, resulting in possible instability of its furnace temperature. Furthermore, during the heating process, the internal structure of the workpiece to be welded was relatively scattered, leading to slight deformation;

[0084] By comparing Example 1 with Comparative Example 4, it can be found that the quality of the welded parts varies with different cleaning agents, and the cleaning agent in Example 1 of the present invention is more suitable;

[0085] By comparing Example 1 with Comparative Example 5, the deformation amount of Example 1 is small. This may be because the tube housing part is a thin - wall part, and the brazing process of the thin - wall part components mainly relies on the limit or positioning tooling to ensure the welding quality. After the product is assembled and pushed into the vacuum furnace, it is not visible, and only experience and experimental results can be used to ensure the welding reliability. Moreover, such thin - wall parts will expand at high temperatures, and the thermal deformation coefficients of each part are different. It is necessary to consider different material expansion coefficients to determine the gap after assembly. Example 1 takes this into account, so a suitable gap is reserved to ensure a lower deformation amount of the welded parts.

Claims

1. A welding method for the shell of a medical CT metal tube, wherein the welding method is completed based on the welding assembly of the shell of the medical CT metal tube, and is characterized in that, The welding assembly includes a base (1), a tooling protection side plate (3) fixed on the base (1) for limiting the CT metal tube housing (2), and an upper fixing seat (4) and a lower fixing seat (5) fixed on the base (1) for assembling the CT metal tube housing (2). The upper fixing seat (4) and the lower fixing seat (5) are clamped by a clamp. The lower fixing seat (5) is clamped to the base (1). A beryllium window welding movable pressure block (6) is provided on the upper fixing seat (4). The welding method of the CT metal tube housing includes the following steps: S1. Assemble the parts to be welded; Clean each component of the CT metal tube housing (2). The components of the CT metal tube housing (2) include a stainless steel ring, a tube housing, a kovar ring, a grounding block, and a beryllium window. First, fit and install the stainless steel ring with the welding assembly for fixing each component, then fit and install the stainless steel ring with the tube housing, then place the kovar ring at the port or connection of the tube housing for assembly and installation. Subsequently, place the beryllium window under the beryllium window welding movable pressure block (6) and use the welding assembly for fastening and fixing. Then assemble the heat dissipation strips and the grounding block to obtain the parts to be welded. Among them, the material of the tube housing is oxygen-free copper. S2. Vacuum welding; First, preheat the vacuum furnace until the temperature inside the vacuum furnace reaches 800 - 900 °C, then cool the vacuum furnace to 400 - 500 °C. Subsequently, place the fitting to be welded into the vacuum furnace. The pressure in the vacuum furnace is less than or equal to 6.5×10 -3 Pa, and heat it up at a rate of 5 - 7 °C / min to T - 20 - T - 10 °C, then perform welding for 0.1 - 5 min to obtain a tooling part; where T is the melting point of the pipe shell; S3. Furnace out and leak detection; After welding is completed, lower the temperature in the vacuum furnace to 100 - 200 °C, then take out the tooling parts and each component and conduct a first leak detection. If there are components that fail the first leak detection, clean the components that fail the first leak detection and repeat step S2 until the first leak detection is qualified and then proceed to the next step; S4. Weld the window area; First, raise the temperature of the vacuum furnace to 400 - 500 °C, rotate the tooling part by 90°, and weld the window area when the temperature rises to T - 20 - T - 10 °C and the welding time is 0.1 - 3 min. Then conduct a second leak detection. If there are components that fail the second leak detection, clean the components that fail the second leak detection and repeat welding the window area; until it is qualified, the welding is completed. In step S1, the cleaning is completed by a first cleaning agent. In S3 and S4, the cleaning is completed by a second cleaning agent. The first cleaning agent includes alkyl glycoside, ethylene glycol monobutyl ether, and glutamic acid tetraacetic acid with a mass ratio of 1:3 - 5:

2. The second cleaning agent includes citric acid, castor oil derivative, borate, and ethylenediaminetetraacetic acid with a mass ratio of 5 - 7:5:2 - 3:

2.

2. The welding method of a medical CT metal tube housing according to claim 1, characterized in that The first leak detection uses the soap solution method, and the second leak detection uses the ultrasonic method or the gas detection method.

3. The welding method of a medical CT metal tube housing according to claim 1, characterized in that The preparation method of the second cleaning agent is as follows: First, add the castor oil derivative to citric acid and mix and stir for 5 - 8 min; the stirring speed is 500 - 600 r / min, then add borate and ethylenediaminetetraacetic acid in sequence and stir for 10 - 20 min; obtain a mixture, and use a pH regulator to adjust the pH of the mixture to 7 to obtain the second cleaning agent.

4. A welding method for the tube shell of a medical CT metal tube, as described in claim 1, characterized in that, In S1, there are gaps between the components of the CT metal tube housing (2).

5. The welding method of a medical CT metal tube housing according to claim 1, characterized in that, The heat dissipation strip is a wavy heat dissipation strip.

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