Radiator surface sealing treatment method

Abstract

The invention discloses a surface sealing treatment method for a radiator. The surface sealing treatment method sequentially comprises the seven steps of acid pickling, first pure water washing, normal-temperature surface sealing treatment, second pure water washing, high-temperature hot water treatment, low-temperature drying and low-temperature baking. Welding pollutants are thoroughly removed through the heated pickling solution; high-temperature and high-purity water is used for removing acid liquor residues; forming a uniform protective layer on the aluminum substrate by adopting normal-temperature confining liquid; washing again to remove redundant treatment liquid; crosslinking and densification of the protective layer are promoted through high-temperature hot water; low-temperature, low-humidity and high-speed clean air is adopted to thoroughly dry a flow channel; and finally, curing the film layer through long-time low-temperature baking. The whole technological process is continuous and automatic, a layer of stable, inert and high-adhesive-force composite protective film is finally formed on the inner surface of the radiator, and the cleanliness and corrosion resistance of the radiator are greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat sinks, in particular to a heat sink surface sealing treatment method. BACKGROUND

[0002] As a kind of efficient and clean energy conversion device, the long-term stable operation of hydrogen fuel cell system highly depends on the reliability of thermal management system. As the core component of cooling liquid circulation, aluminum heat sink plays a key role in maintaining the operating temperature of the stack. However, the working environment of the heat sink is particularly harsh: the cooling medium flowing inside must be deionized liquid with extremely low electrical conductivity, and the dissolution of any metal ions may lead to the risk of internal short circuit of the battery stack; At the same time, the welding forming process inevitably leaves oxides, flux and other pollutants on the surface of the flow channel, which not only becomes a continuous source of pollution, but also may induce local corrosion and accelerate the ion precipitation process. Therefore, it is urgent to develop a heat sink surface sealing treatment method to fundamentally improve the initial cleanliness and long-term corrosion resistance of the heat sink cavity, and to ensure the long-term stability of the physicochemical parameters of the cooling liquid, which has important engineering significance for the reliability improvement and life extension of the entire fuel cell system. SUMMARY

[0003] The purpose of the present application is to solve the problems in the background art and provide a heat sink surface sealing treatment method.

[0004] The above technical purpose of the present application is achieved by the following technical scheme: A heat sink surface sealing treatment method, comprising the following steps: S1, pickling: the inlet and outlet of the heat sink are placed upward, and the heat sink is transported to the pickling area through the roller conveying line of the surface sealing treatment equipment, the pickling liquid is heated to 60-70 DEG C, and then the inner flow channel of the heat sink is circulated and washed for 5-15 min, S2, first pure water washing: the heat sink is transported to the first washing area of the surface sealing treatment equipment, the pure water with an ion concentration of less than 1 µS / cm is heated to 60-70 DEG C, and then the heat sink treated in the step is circulated and washed for 30-50 min; S3, surface sealing treatment: the heat sink is transported to the surface sealing treatment area of the surface sealing treatment equipment, and the sealing treatment liquid is used to circulate and wash the heat sink washed in the step at room temperature for 5-15 min; S4, second pure water washing: the heat sink is transported to the second washing area of the surface sealing treatment equipment, and the pure water with an ion concentration of less than 1 µS / cm is used to wash the heat sink treated in the step at room temperature for 15-25 min; S5, Hot water treatment: The radiator is transported to the hot water zone of the surface sealing treatment equipment, and the radiator after the step rinsing is rinsed for 25-35 minutes at 90-100℃ using pure water with an ion concentration of less than 1µS / cm. S6, Drying: The radiator is transported to the drying area of ​​the surface sealing treatment equipment, and clean air is used to blow the radiator after the hot water treatment step for 20-40 minutes. The temperature of the clean air is 50-60℃, the humidity is less than 20%, and the outlet flow rate is greater than 4m / s. S7, Baking: The radiator is conveyed to the hot air baking mechanism of the surface sealing treatment equipment, and the radiator after the drying process is baked at 85-95℃ for 3-5 hours.

[0005] This invention addresses the problem of residual oxide scale, flux, and grease from welding, which are difficult to completely remove and thus affect the quality and long-term reliability of the subsequent film formation, through step S1, which uses a specially formulated heated pickling solution to circulate and rinse the internal channels of the radiator. Step S2, using high-temperature, low-ion-concentration pure water for a prolonged circulating rinse, solves the problem of residual acid and ions after pickling potentially interfering with subsequent sealing treatment and causing potential corrosion. Step S3, using a sealing treatment solution with a specific composition at room temperature for circulating treatment, directly forms a uniform and dense protective layer on the aluminum surface. Step S4, a second pure water rinse, solves the problem of residual treatment solution after sealing treatment potentially crystallizing and contaminating the channels, affecting the purity and adhesion of the final film. Step S5, using high-temperature, high-purity water for a prolonged hot water treatment, solves the problems of insufficient cross-linking of the protective layer, incomplete closure of micropores, and weak adhesion between the film and the substrate. The process significantly improves the density, chemical stability, and adhesion of the membrane layer. Step S6, using low-temperature, low-humidity, and high-speed clean air for purging and drying, solves the technical challenges of complex internal flow channel structures and the difficulty in completely removing residual moisture, which can easily lead to membrane blistering or water stains during subsequent baking. Step S7, using long-term low-temperature baking at a specific temperature, solves the problems of incomplete curing of the protective layer and insufficient release of internal stress, resulting in insufficient long-term thermal cycling resistance and resistance to media erosion. The entire process system, through a continuous and controllable automated process, forms an extremely stable, inert, and highly adhesive protective film on the inner surface of the aluminum radiator, greatly improving the cleanliness and corrosion resistance of the water tank. It effectively inhibits the precipitation of aluminum ions into the coolant during the long-term operation of the hydrogen fuel cell system, ensuring the long-term stability of the coolant conductivity and the permanent cleanliness of the radiator interior, ultimately meeting the stringent requirements of the hydrogen fuel cell system for long life and high reliability of core cooling components.

[0006] The pickling solution comprises, by mass percentage: 1-2% anionic surfactant, 1-2% nonionic surfactant, 3-7% hydrofluoric acid, with the remainder being pure water; the sealing treatment solution comprises, by mass percentage: less than 1.0% organic compounds, less than 1.4% nitrates, with the remainder being deionized water.

[0007] This invention solves several core technological challenges in the surface treatment of aluminum heat sinks for hydrogen fuel cells through the synergistic effect of a pickling solution with a specific formulation and a sealing treatment solution. The hydrofluoric acid in the pickling solution effectively dissolves and peels off the stubborn alumina layer and flux residue in the welding area of ​​the aluminum material through its strong complexing and corrosive effects. At the same time, by compounding anionic and nonionic surfactants, the surface tension of the cleaning solution is reduced and the ability to penetrate, emulsify and disperse oil stains and particulate impurities is enhanced, thus solving the problem of difficult physical removal of pollutants in complex flow channels. Nitrates in the sealing solution act as oxidation promoters, gently oxidizing the aluminum surface to form a dense alumina transition layer, solving the problem of weak adhesion between the substrate and the organic layer when directly forming the film. The organic binders, through adsorption and cross-linking, construct a continuous and stable organic-inorganic hybrid protective film on the oxide transition layer. This film can be formed at room temperature, solving the problems of high energy consumption and uneven film formation on the aluminum surface in traditional high-temperature passivation processes. The two-liquid system, through stepwise action, first thoroughly cleans and activates the substrate, and then constructs the composite protective layer, jointly solving the fundamental problem of long-term precipitation of aluminum ions from microscopic defects leading to increased conductivity of the coolant. Ultimately, it achieves high cleanliness and superior corrosion resistance stability of the radiator's internal flow channels during long-term use.

[0008] Preferably, the surface sealing treatment equipment includes a frame and a roller conveyor line. The frame is provided with a pickling area, a first rinsing area, a surface sealing treatment area, a second rinsing area, a hot water area, and a drying area from left to right. The roller conveyor line runs through all the above areas. A hot air baking mechanism is also provided on the right side of the drying area.

[0009] This invention integrates the pickling zone, first rinsing zone, surface sealing treatment zone, second rinsing zone, hot water zone, drying zone, and hot air baking mechanism sequentially along a roller conveyor line onto the same frame, constructing a highly continuous and automated closed-loop processing line. This solves the problems of secondary contamination risks, low process connection efficiency, and large production space occupation caused by multiple transfers of radiators in traditional segmented processing processes. The continuous through-type design of the roller conveyor line achieves seamless connection and precise positioning and transportation of radiators between various functional areas, solving the problems of surface damage, cross-contamination of treatment fluids, and unstable production rhythm that may be caused by manual handling or hoisting. It also solves the industrialization problems of difficulty in unified control of environmental variables and insufficient consistency and traceability of final treatment quality when multiple processes are carried out in a decentralized manner.

[0010] Preferably, the pickling zone, the first rinsing zone, the surface sealing treatment zone, the second rinsing zone, and the hot water zone each include a liquid storage tank, an automatic docking and disengagement structure, and a radiator positioning structure. The roller conveyor line is located above the liquid storage tank, and the radiator positioning structure is symmetrically arranged on both sides of the traveling direction of the roller conveyor line for centering or clamping and positioning the radiator from both sides when it reaches the work station. The automatic docking and disengagement structure is located above the roller conveyor line.

[0011] This invention utilizes radiator positioning structures symmetrically arranged on both sides of the roller conveyor line to automatically center and clamp the radiators upon arrival at each station. This solves the positioning accuracy problems caused by inaccurate alignment and poor sealing of the radiator flow channel interface and cleaning nozzle due to manual placement or conveying deviations, which can lead to leakage of the treatment fluid or cleaning blind spots. Through an automatic docking and disengagement structure set above the roller conveyor line, the invention achieves rapid, reliable, and automatic connection and separation between the treatment fluid pipeline and the radiator inlet and outlet. This ensures that each station can achieve fully automatic and sealed fluid treatment after the radiator is accurately positioned, realizing an automatic radiator encapsulation process.

[0012] This invention solves the problems of cross-contamination of processed liquids, difficulty in classifying and recycling waste liquids, and difficulty in maintaining the temperature and concentration of process liquids by setting up independent liquid storage tanks below each functional area.

[0013] The drying zone of this invention is also equipped with a radiator positioning structure and an automatic docking and disconnection structure. The drying zone uses clean air to be delivered in the fluid input pipe and the fluid output pipe.

[0014] Preferably, the automatic docking and disengagement structure includes a fluid input pipe, a fluid output pipe, a connecting plate, and an electric telescopic rod. The fluid input pipe and the fluid output pipe are located on the connecting plate. The motor end of the electric telescopic rod is located on the frame. The push rod end of the electric telescopic rod is fixedly connected to the connecting plate. The fluid input pipe is connected to the output port of the liquid storage tank via a flexible hose. The fluid output pipe is connected to the input port of the liquid storage tank via a pump and a flexible hose. The fluid input pipe and the fluid output pipe are rigid pipes.

[0015] This invention controls the vertical movement of the connecting plate using an electric telescopic rod, enabling rapid, precise, and automatic docking and disconnection of fluid input and output pipes with the radiator inlet and outlet, thus facilitating automated radiator sealing. By rigidly integrating the fluid input and output pipes onto the same connecting plate, it ensures that the center distance between the two pipes is perfectly matched with the radiator interface and that their relative positions are fixed. This solves the reliability problem of pipe kinking and misalignment that can easily occur when using independent flexible hoses for docking, leading to sealing failure or fluid leakage.

[0016] This invention, by retaining the intermediate section of the flexible hose connected to the liquid storage tank, absorbs minor vibrations and alignment deviations during equipment operation while also enabling flexible movement of the rigid terminal pipeline.

[0017] Preferably, both the fluid inlet pipe and the fluid outlet pipe include a pipe body and a pneumatic sealing ring, with the pneumatic sealing ring surrounding the bottom of the pipe body.

[0018] This invention utilizes a pneumatic inflation and deflation principle to control the expansion and contraction of the sealing ring, achieving rapid and flexible adaptive sealing between the pipe and radiator interface. After inflation, the pneumatic sealing ring can uniformly conform to the interface end faces of different sizes, forming a full-circumferential seal without dead angles. This solves the sealing reliability problem caused by insufficient local sealing pressure under complex working conditions, leading to leakage of treatment fluid, decreased flushing pressure, and thus affecting the cleaning and treatment effect of the internal flow channel. This sealing method only requires low-pressure contact during docking, and exhausts and contracts during disengagement to achieve zero-friction separation. It solves the problem of huge docking pressure required for mechanical pressing seals and physical damage to the interface caused by frequent insertion and removal, significantly improving the service life of the equipment and radiator interface and the reliability of fully automatic operation.

[0019] Preferably, the radiator positioning structure includes a linear drive device, a positioning force transmission plate, and an adaptive V-shaped positioning head. The linear drive device is fixed on the frame, the positioning force transmission plate is connected to the output end of the linear drive device, and the bottom of the adaptive V-shaped positioning head is provided with a pivot shaft. The pivot shaft cooperates with the shaft hole opened at the end of the positioning force transmission plate to form a rotatable connection. An elastic reset member that provides a reset torque is sleeved on the pivot shaft.

[0020] This invention uses a linear drive device to move the positioning force transmission plate. The adaptive V-shaped positioning head is initially in a V-shape. During the movement, the adaptive V-shaped positioning head rotates around the pivot, generating a thrust perpendicular to the direction of movement of the positioning force transmission plate. When the positioning force transmission plate is in place, the adaptive V-shaped positioning head becomes an L-shape and fits against the four corners of the radiator, completing the centering and positioning of the radiator. This precise positioning of the radiator can compensate for the slight lateral positional deviation of the radiator on the roller conveyor line due to placement or its own structure, solving the positioning accuracy problem of fluid pipeline docking failure caused by the accumulation of positional deviation.

[0021] Preferably, the hot air baking mechanism includes a rotary motor, a polygonal baking drum, a drum spindle, an internal conveyor belt, a material separating unit, and a sealing cover. The polygonal baking drum is supported between the frame by the drum spindles at both ends. The drum spindle and the rotary motor are connected by gear meshing. The output end of the rotary motor is provided with a driving gear, and the drum spindle is provided with a driven gear. The driving gear and the driven gear mesh, and the rotary motor drives the entire baking drum to rotate around its axis. Multiple material separating units are evenly arranged circumferentially on the inner sidewall of the polygonal baking drum. The internal conveyor belt is laid in each material separating unit. The internal conveyor belt is used to receive the radiator conveyed from the drum conveyor line. The sealing cover covers the opening of the material separating unit to form a closed baking chamber.

[0022] This invention achieves the transport of radiators from the drying zone to the baking chamber by laying an internal conveyor belt in each partition unit and seamlessly connecting it with the external roller conveyor line. Then, by uniformly arranging multiple independent partition units along the circumference on the inner wall of the polygonal roller, each unit constitutes an independent closed baking chamber, enabling the simultaneous batch processing of multiple radiators. This solves the space efficiency problems of traditional single-layer static baking, which has a large footprint and low production capacity due to long baking time. It simultaneously achieves uniform heating, batch processing and automated flow in a compact space, significantly improving the efficiency and reliability of the final curing process.

[0023] Preferably, the interior of the roller spindle is a cavity, with an open end on the right and a closed end on the left. Sealed bearings are fixed to both ends of the roller spindle and are mounted on the frame. The inner ring of the sealed bearing is fixedly connected to the outer wall of the roller spindle. A hot air inlet pipe is fixed to the outer ring of the sealed bearing on the right side of the roller spindle, and a return air inlet pipe is fixed to the outer ring of the sealed bearing on the left side of the roller spindle. The right end of the return air inlet pipe is closed, and a return air pipe is provided on the side wall of the return air inlet pipe. The roller spindle is divided into a non-conductive inlet section and an outlet section. The inlet section of the roller spindle, located in the area of ​​the material separation unit, has several radially extending outlet pipes. Each material separation unit corresponds to one outlet pipe. A return air port is provided on the outlet section, and the return air port is connected to the side wall of the material separation unit via a pipe. Each outlet pipe is equipped with a valve, ensuring that hot air enters only after a radiator has entered the corresponding material separation unit, thus improving energy efficiency and environmental friendliness.

[0024] In this invention, hot air is introduced through a hot air inlet pipe fixed to the right side of the frame. This pipe is connected to the stationary outer ring of the right-side sealed bearing. The hot air then enters the cavity inside the right-side opening of the main shaft of the roller, which rotates synchronously with the inner ring of the bearing. The inside of the main shaft is divided into an inlet section and an outlet section that do not communicate with each other by a partition. When the hot air flows through the inlet section, it is precisely distributed to each corresponding material separation unit through multiple radial outlet pipes provided on the section. After heat exchange, the gas is collected from the side wall of each material separation unit through pipes to the return air port of the main shaft outlet section and flows along the left-side cavity. Ultimately, the exhaust gas is discharged from the system through the return air inlet pipe fixed to the stationary outer ring of the left-side sealed bearing and the return air pipe on its side wall, thus forming a complete closed airflow loop with air intake at the right end, return air at the left end, and coaxial circulation. This fundamentally solves the problem of fluid transport from fixed pipelines to high-speed rotating multi-position drums. It replaces the traditional multi-path external rotating distributor with a single hollow main shaft, greatly simplifies the system structure, promotes the uniformity of the temperature field inside the drum, and improves the utilization efficiency of hot air energy.

[0025] Preferably, the sealing cover includes a horizontal plate and a vertical plate, which facilitates the entry of the radiator and forms a sealed baking chamber after the cover is closed.

[0026] Preferably, the internal conveyor belt is a mesh conveyor belt.

[0027] The mesh structure of this invention ensures sufficient load-bearing strength while allowing hot air from the exhaust duct to fully penetrate the conveyor belt and act directly on the radiator without obstruction. This solves the problem of hot air not being able to enter due to large-area obstruction in traditional solid conveyor belts. The porous structure of the mesh ensures that the hot air is more uniform in the chamber, avoids the formation of high-temperature areas due to stagnant airflow at the bottom, and solves the problem of poor local curing caused by dead corners of hot air circulation in a confined space.

[0028] In summary, the beneficial effects of this invention are as follows: 1. This invention solves the problem of the difficulty in completely removing contaminants such as residual oxide scale, flux, and grease from welding, which affects the quality and long-term reliability of subsequent film formation, by using a specially formulated heated pickling solution to circulate and rinse the internal channels of the radiator in step S1; by using high-temperature, low-ion-concentration pure water for long-term circulation rinsing in step S2, it solves the problem that residual acid and ions after pickling may interfere with subsequent sealing treatment and cause potential corrosion hazards; by using a sealing treatment solution with a specific composition at room temperature for circulation treatment in step S3, a uniform and dense protective layer is directly formed on the aluminum surface; by using a second pure water rinse in step S4, it solves the problem that residual treatment solution on the surface after sealing treatment may crystallize and contaminate the channels, affecting the purity and adhesion of the final film layer; by using high-temperature, high-purity water for long-term hot water treatment in step S5, it solves the problems of insufficient cross-linking degree of the protective layer, incomplete closure of micropores, and weak bonding between the film layer and the substrate. This process significantly improves the density, chemical stability, and adhesion of the membrane layer. Step S6 uses low-temperature, low-humidity, high-speed clean air for purging and drying, solving the technical problem of complex internal flow channel structure and difficulty in completely removing residual moisture, which can easily lead to membrane blistering or water stains during subsequent baking. Step S7 uses long-term low-temperature baking at a specific temperature, solving the problem of incomplete curing of the protective layer and insufficient release of internal stress, resulting in insufficient long-term heat cycle resistance and resistance to media erosion. The entire process system forms an extremely stable, inert, and highly adhesive protective film on the inner surface of the aluminum radiator through a continuous and controllable automated process, greatly improving the cleanliness and corrosion resistance of the water tank, effectively inhibiting the precipitation of aluminum ions into the coolant during the long-term operation of the hydrogen fuel cell system, ensuring the long-term stability of the coolant conductivity and the permanent cleanliness of the radiator interior, and ultimately meeting the stringent requirements of the hydrogen fuel cell system for long life and high reliability of core cooling components. 2. This invention integrates the pickling zone, first rinsing zone, surface sealing treatment zone, second rinsing zone, hot water zone, drying zone, and hot air baking mechanism sequentially along the roller conveyor line onto the same frame, constructing a highly continuous and automated closed-loop processing line. This solves the problems of secondary pollution risk, low process connection efficiency, and large production space occupation caused by multiple transfers of radiators in traditional segmented processing processes. The continuous through-type design of the roller conveyor line achieves seamless connection and precise positioning and conveying of radiators between various functional areas, solving the problems of surface damage, cross-contamination of treatment liquids, and unstable production rhythm that may be caused by manual handling or hoisting. It also solves the industrialization problem of difficulty in unified control of environmental variables and insufficient consistency and traceability of final treatment quality when multiple processes are carried out in a decentralized manner. 3. This invention, through a radiator positioning structure symmetrically arranged on both sides of the roller conveyor line, achieves automatic centering and clamping fixation when the radiator arrives at each station. This solves the positioning accuracy problem caused by inaccurate alignment and poor sealing of the radiator flow channel interface and cleaning nozzle due to manual placement or conveying deviation, which leads to leakage of the treatment fluid or cleaning blind spots. Through the automatic docking and disengagement structure set above the roller conveyor line, the quick, reliable and automatic connection and separation of the treatment fluid pipeline and the radiator inlet and outlet are realized, thereby ensuring that each station can achieve fully automatic and sealed fluid treatment after the radiator is accurately positioned, realizing the automatic sealing process of the radiator. 4. This invention achieves the conveying of radiators from the drying zone to the baking chamber by laying an internal conveyor belt in each material separation unit and seamlessly connecting it with the external roller conveyor line. Then, by uniformly arranging multiple independent material separation units along the circumference on the inner wall of the polygonal roller, each unit constitutes an independent closed baking chamber, enabling the simultaneous batch processing of multiple radiators. This solves the space efficiency problem of traditional single-layer static baking, which has a large footprint and low production capacity due to long baking time. It simultaneously achieves uniform heating, batch processing and automated flow in a compact space, significantly improving the efficiency and reliability of the final curing process. 5. This invention controls the vertical movement of the connecting plate via an electric telescopic rod, enabling rapid, precise, and automatic docking and disconnection of fluid input and output pipes with the radiator inlet and outlet, thus facilitating automated radiator sealing. By rigidly integrating the fluid input and output pipes onto the same connecting plate, it ensures that the center distance between the two pipes is perfectly matched with the radiator interface and that their relative positions are fixed, solving the reliability problem of pipe kinking and misalignment that can easily occur when using independent flexible hoses for docking, leading to sealing failure or fluid leakage. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the process of the present invention; Figure 2 This is an overall schematic diagram of the surface sealing treatment equipment of the present invention; Figure 3 This is a schematic diagram of the heat sink positioning structure of the present invention; Figure 4 This is a schematic diagram of the elastic reset component of the present invention; Figure 5 This is a cross-sectional schematic diagram of the fluid input pipe and the inlet connection of the radiator of the present invention; Figure 6 This is a three-dimensional schematic diagram of the hot air baking mechanism of the present invention; Figure 7 This is a side view schematic diagram of the hot air baking mechanism of the present invention; Figure 8 This is a cross-sectional schematic diagram of the drum spindle of the present invention; Figure 9 This is a three-dimensional schematic diagram of the drum spindle of the present invention; Figure 10 This is a schematic diagram of the sealing cover plate of the present invention; Figure 11 This is a schematic diagram of the inner wall of the radiator treated according to the present invention; Figure 12 This is a microscopic schematic diagram of the surface of the heat sink before processing according to the present invention; Figure 13 This is a microscopic schematic diagram of the surface of the heat sink after processing according to the present invention. Detailed Implementation

[0030] The following specific embodiments are merely illustrative of the present invention and are not intended to limit the invention. Those skilled in the art can make modifications to these embodiments without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0031] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] Example 1

[0033] like Figure 1 As shown, a method for sealing the surface of a radiator includes the following steps: S1, Pickling: Place the radiator with its inlet and outlet facing upwards, and transport it to the pickling zone 11 through the roller conveyor of the surface sealing treatment equipment 1. Heat the pickling solution to 65°C and then circulate and rinse the inner flow channel of the radiator for 10 minutes. S2, First pure water rinse: The radiator is transported to the first rinsing zone 12 of the surface sealing treatment equipment 1. Pure water with an ion concentration of less than 1µS / cm is heated to 65°C and then the radiator after step 1 is circulated and rinsed for 40 minutes. S3, Surface sealing treatment: The radiator is transported to the surface sealing treatment area 13 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 2 is circulated and rinsed for 10 minutes at room temperature using sealing treatment liquid. S4, Second pure water rinse: The radiator is transported to the second rinsing zone 14 of the surface sealing treatment equipment 1, and the radiator after step 3 is rinsed for 20 minutes at room temperature using pure water with an ion concentration of less than 1µS / cm. S5, Hot water treatment: The radiator is transported to the hot water zone 15 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 4 is rinsed for 305 minutes at 95°C using pure water with an ion concentration of less than 1µS / cm. S6, Drying: The radiator is transported to the drying zone 16 of the surface sealing treatment equipment 1. The radiator after hot water treatment in step 5 is purged with clean air for 30 minutes. The temperature of the clean air is 55℃, the humidity is less than 20%, and the outlet flow rate is greater than 4m / s. S7, Baking: The radiator is conveyed to the hot air baking mechanism 17 of the surface sealing treatment equipment 1 and baked at 90°C for 4 hours after the radiator is dried in step 5.

[0034] Pickling solution: 1.5% anionic surfactant, 1.5% nonionic surfactant, and 5% hydrofluoric acid are added to an appropriate amount of pure water, stirred and mixed evenly, and then made up to 100% with pure water.

[0035] Sealing solution: 0.8% by mass of organic titanate complex and 1.2% zirconium nitrate are added to an appropriate amount of deionized water, stirred until completely dissolved, and then made up to 100% with deionized water.

[0036] like Figure 2 As shown, the surface sealing treatment equipment 1 includes a frame 18 and a roller conveyor line 19. From left to right, the frame is arranged with an acid pickling zone 11, a first rinsing zone 12, a surface sealing treatment zone 13, a second rinsing zone 14, a hot water zone 15, and a drying zone 16. The roller conveyor line 19 runs through all the above zones. A hot air baking mechanism 17 is also provided on the right side of the drying zone 16. The acid pickling zone 11, the first rinsing zone 12, the surface sealing treatment zone 13, the second rinsing zone 14, and the hot water zone 15 all include a liquid storage tank 161, an automatic docking and disengagement structure 162, and a radiator positioning structure 20. The roller conveyor line 19 is located above the liquid storage tank 161, and the radiator positioning structure (20) is symmetrically arranged in the direction of travel of the roller conveyor line (19). The two sides are used for centering or clamping the radiator when it arrives at the work station. The automatic docking and disengagement structure 162 is located above the roller conveyor line 19. The automatic docking and disengagement structure 162 includes a fluid input pipe 1621, a fluid output pipe 1622, a connecting plate 1623, and an electric telescopic rod 1624. The fluid input pipe 1621 and the fluid output pipe 1622 are located on the connecting plate 1623. The motor end of the electric telescopic rod 1624 is located on the frame 18. The push rod end of the electric telescopic rod 1624 is fixedly connected to the connecting plate 1623. The fluid input pipe 1621 is connected to the output port of the liquid storage tank 161. The fluid output pipe 1622 is connected to the input port of the liquid storage tank 161 through a pump.

[0037] like Figure 5 As shown, both the fluid inlet pipe 1621 and the fluid outlet pipe 1622 include a pipe body 1626 and a pneumatic sealing ring 1627, with the pneumatic sealing ring 1627 surrounding the bottom of the pipe body 1626.

[0038] likeFigures 3-4 As shown, the radiator positioning structure 20 includes a linear drive device 201, a positioning force transmission plate 202, and an adaptive V-shaped positioning head 203. The linear drive device 201 is fixed on the frame 18. The positioning force transmission plate 202 is connected to the output end of the linear drive device 201. The bottom of the adaptive V-shaped positioning head 203 is provided with a pivot shaft 204. The pivot shaft 204 cooperates with the shaft hole opened at the end of the positioning force transmission plate 202 to form a rotatable connection. An elastic reset member 205 that provides a reset torque is sleeved on the pivot shaft 204. The elastic reset member is a torsion spring.

[0039] like Figures 6-10 As shown, the hot air baking mechanism 17 includes a rotary motor 172, a polygonal baking drum 173, a drum spindle 174, an internal conveyor belt 174, a material separating unit 177, and a sealing cover plate 178. The polygonal baking drum 173 is supported between the frame 18 by the drum spindles 174 at both ends. The drum spindle (174) is connected to the rotary motor (172) through gear meshing. The rotary motor 172 drives the entire baking drum to rotate around its axis. Multiple material separating units are evenly arranged circumferentially on the inner wall of the polygonal baking drum 173. The material handling unit 177 has an internal conveyor belt 174 inside, which receives the radiators conveyed from the roller conveyor line 19. A sealing cover 178 covers the opening of the material handling unit 177 to form a closed baking chamber. The sealing cover is connected to the material handling unit via an electric push rod, enabling automatic opening and closing. This is a relatively mature existing technology and will not be elaborated upon here. The sealing cover 178 includes a horizontal plate 1781 and a vertical plate 1782. The interior of the roller main shaft 174 is a cavity. The left end is an open end, and the right end is a closed end. Sealed bearings 30 are fixed to both ends of the roller main shaft 174, and the sealed bearings 30 are fixed to the frame 18. The inner ring of the sealed bearing 30 is fixedly connected to the outer wall of the roller main shaft 174. A hot air inlet pipe 31 is fixed to the outer ring of the sealed bearing 30 on the right side of the roller main shaft 174, and a return air inlet pipe 32 is fixed to the outer ring of the sealed bearing 30 on the left side of the roller main shaft 174. The right end of the return air inlet pipe 32 is a closed end, and a return air pipe 33 is provided on the side wall of the return air inlet pipe 32. 74 is divided into a non-conductive air inlet section 34 and an air outlet section 35. The air inlet section 34 of the roller main shaft 174 is located in the area of ​​the material separation unit 177 and is provided with several radially extending air outlet pipes 36. Each material separation unit 177 corresponds to one air outlet pipe 36. The air outlet section 35 is provided with a return air port 351. The return air port 351 and the side wall of the material separation unit 177 are connected by a pipe. Each air outlet pipe 36 is provided with a valve so that hot air will only enter after the corresponding material separation unit has a radiator, which is more energy-saving and environmentally friendly. The internal conveyor belt 174 is a mesh conveyor belt.

[0040] Working principle: such as Figures 1-13As shown, after the system starts, the aluminum radiators to be processed are neatly placed at the starting end of the roller conveyor line 19, with their inlet and outlet facing upwards to ensure the accuracy of subsequent docking. The roller conveyor line 19 starts running, smoothly transporting the first radiator to the pickling area 11. When the radiator reaches the preset position of the pickling station, the radiator positioning structure 20, symmetrically arranged on both sides of the roller conveyor line 19, immediately starts. Its linear drive device 201 pushes the positioning force transmission plate 202 to move towards the radiator. When the adaptive V-shaped positioning head 203 at the end contacts the side of the radiator, it will adaptively rotate around the pivot axis 204. The elastic reset member 205 ensures that it always applies a vertical and uniform clamping force, thereby accurately centering and fixing the radiator and compensating for any slight positional deviation that may occur during the conveying process. After the radiator is accurately positioned, the automatic docking and undoing structure 162 located above the roller conveyor line 19 starts to operate. The electric telescopic rod 1624 drives the connecting plate 1623 to descend vertically. The fluid inlet pipe 1621 and fluid outlet pipe 1622, rigidly fixed to the connecting plate 1623, fall precisely accordingly. The pneumatic sealing ring 1627 at the bottom of the pipe body 1626 immediately inflates upon contact with the inlet and outlet faces of the radiator, forming a flexible, full-circumferential seal, thus establishing a tight connection with the radiator flow channel. Simultaneously, the pickling solution in the liquid storage tank 161 of the pickling zone 11 is heated to 60-70°C. The circulation pump starts, pumping the heated pickling solution into the radiator flow channel through the fluid inlet pipe 1621 to circulate and flush away residual oxide scale, flux, and grease. The flushed waste liquid returns to the storage tank through the fluid outlet pipe 1622. After 5-15 minutes of processing, the electric telescopic rod 1624 raises the connecting plate 1623, the pneumatic sealing ring 1627 deflates and contracts, the pipes separate from the radiator, the positioning structure loosens, and the pickling step is completed. Subsequently, the roller conveyor 19 delivers the radiator into the first pure water rinsing zone 12, where the radiator undergoes an automatic positioning and pipeline connection process similar to that in the pickling zone 11. High-purity water with an ion concentration of less than 1 µS / cm is heated to 60-70°C and circulated at a high flow rate for 30-50 minutes through the internal channels of the radiator. The purpose is to thoroughly remove residual acid and all free ions, creating an absolutely clean and activated aluminum-based surface for the next film formation step. After deep rinsing, the radiator is transported to the surface sealing treatment zone 13. Room temperature sealing solution is pumped into the radiator's internal channels for 5-15 minutes of circulation, forming a protective layer on the aluminum surface. Immediately afterwards, the radiator enters the second pure water rinsing zone 14, where it is rinsed with room temperature high-purity water for 15-25 minutes. This process removes any remaining unreacted treatment solution, prevents crystallization contamination, and ensures the purity of the final film. Subsequently, the radiator is fed into hot water zone 15, where high-temperature, high-purity water at 90-100℃ is pumped into the flow channel for 25-35 minutes of circulation. This high-temperature environment greatly promotes the further hydrolysis and condensation reaction of the protective film molecules, strengthening its chemical cross-linking network; at the same time, the high-temperature effect helps to close the micropores of the film and significantly enhances the bonding force between the film and the aluminum substrate, making the protective layer denser, more stable, and stronger. After hot water treatment, the radiator reaches a high temperature and then enters the drying zone 16. In this zone, the automatic docking structure 162 connects the pipe for delivering clean air to the radiator. Clean air with a temperature of 50-60℃, humidity below 20%, and flow rate above 4m / s is continuously blown into the radiator's internal channels for 20-40 minutes of powerful purging. This process utilizes the residual heat of the high-temperature workpiece and the carrying effect of the low-humidity, high-speed airflow to efficiently evaporate and remove all residual moisture from the channels, thus preparing the radiator for final baking and eliminating the risk of film blistering due to residual moisture. After thorough drying, the radiator is sent to the hot air baking mechanism 17 by the roller conveyor line 19. The polygonal baking roller 173 in the mechanism rotates slowly under the drive of the rotary motor 172. The internal conveyor belt 174 in one of its partition units 177 connects with the external conveyor line, receiving the radiator and sending it into the closed partition unit 177. Then the sealing cover plate 178 closes, forming an independent baking chamber. In the chamber, hot air is introduced by the hot air inlet pipe 31 fixed on the right side of the frame. This pipe is connected to the stationary outer ring of the right-side sealed bearing 30. The hot air then enters the cavity at the right end of the roller main shaft 174, which rotates synchronously with the inner ring of the bearing. The inside of the main shaft is divided into a non-communicating air inlet section 34 and an air outlet section 35 by a partition. When the hot air flows through the air inlet section, it is precisely distributed to each corresponding partition unit 177 through multiple radial air outlet pipes 36 provided on this section. After heat exchange, the gas is collected from the side wall of each partition unit through pipes to the return air port 351 of the main shaft air outlet section 35 and flows along the left end cavity. Finally, the exhaust gas is discharged through the return air inlet pipe 32 fixed to the stationary outer ring of the left-side sealed bearing 30 and the return air pipe 33 on its side wall, forming a uniform and stable hot air that penetrates the mesh conveyor belt from top to bottom, completely enveloping the radiator. Because the outlet pipe 36 is equipped with a valve, only the outlet pipe corresponding to the material-separating unit where the radiator has entered will open. At a temperature of 85-95℃, the radiator is baked for 3-5 hours. During this process, the internal stress of the protective film layer is fully released, and the curing reaction is completely completed, forming a final highly stable and inert protective layer. After baking, the radiator is removed, completing the entire surface sealing treatment. The entire process, through the continuous flow of the roller conveyor line 19 and the precise coordination of the automated devices at each station, achieves seamless connection and unmanned operation of the entire process from cleaning, film formation, strengthening to curing, ensuring that each radiator achieves a consistent and high-quality surface treatment effect.

[0041] Example 2

[0042] Unlike Example 1, A method for sealing the surface of a heat sink includes the following steps: S1, Pickling: The radiator is placed with its inlet and outlet facing upwards and conveyed to the pickling zone 11 via the roller conveyor of the surface sealing treatment equipment 1. The pickling solution is heated to 60°C and then circulated and rinsed through the inner flow channels of the radiator for 5 minutes. S2, First pure water rinse: The radiator is transported to the first rinsing zone 12 of the surface sealing treatment equipment 1. Pure water with an ion concentration of less than 1µS / cm is heated to 60°C, and then the radiator after step 1 is circulated and rinsed for 30 minutes. S3, Surface sealing treatment: The radiator is transported to the surface sealing treatment area 13 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 2 is circulated and rinsed for 5 minutes at room temperature using sealing treatment liquid; S4, Second pure water rinse: The radiator is transported to the second rinsing zone 14 of the surface sealing treatment equipment 1, and the radiator after step 3 is rinsed for 15 minutes at room temperature using pure water with an ion concentration of less than 1µS / cm. S5, Hot water treatment: The radiator is transported to the hot water zone 15 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 4 is rinsed for 25 minutes at 90°C using pure water with an ion concentration of less than 1µS / cm. S6, Drying: The radiator is transported to the drying zone 16 of the surface sealing treatment equipment 1. The radiator after hot water treatment in step 5 is purged with clean air for 20 minutes. The temperature of the clean air is 50℃, the humidity is less than 20%, and the outlet flow rate is greater than 4m / s. S7, Baking: The radiator is conveyed to the hot air baking mechanism 17 of the surface sealing treatment equipment 1 and baked at 85°C for 3 hours after the drying treatment in step 5.

[0043] Pickling solution: 1.0% anionic surfactant, 2.0% nonionic surfactant, and 3.5% hydrofluoric acid are added to an appropriate amount of pure water, stirred and mixed evenly, and then made up to 100% with pure water.

[0044] Sealing solution: 0.5% by mass of organic titanate complex and 1.0% zirconium nitrate are added to an appropriate amount of deionized water, stirred until completely dissolved, and then made up to 100% with deionized water.

[0045] Example 3

[0046] Unlike Example 1, A method for sealing the surface of a heat sink includes the following steps: S1, Pickling: The radiator is placed with its inlet and outlet facing upwards and conveyed to the pickling zone 11 via the roller conveyor of the surface sealing treatment equipment 1. The pickling solution is heated to 70°C and then circulated and rinsed through the inner flow channels of the radiator for 15 minutes. S2, First pure water rinse: The radiator is transported to the first rinsing zone 12 of the surface sealing treatment equipment 1. Pure water with an ion concentration of less than 1µS / cm is heated to 70°C, and then the radiator after step 1 is circulated and rinsed for 50 minutes. S3, Surface sealing treatment: The radiator is transported to the surface sealing treatment area 13 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 2 is circulated and rinsed for 15 minutes at room temperature using sealing treatment liquid. S4, Second pure water rinse: The radiator is transported to the second rinsing zone 14 of the surface sealing treatment equipment 1, and the radiator after step 3 is rinsed for 25 minutes at room temperature using pure water with an ion concentration of less than 1µS / cm. S5, Hot water treatment: The radiator is transported to the hot water zone 15 of the surface sealing treatment equipment 1, and the radiator after rinsing in step 4 is rinsed for 35 minutes at 100°C using pure water with an ion concentration of less than 1µS / cm. S6, Drying: The radiator is transported to the drying zone 16 of the surface sealing treatment equipment 1. The radiator after hot water treatment in step 5 is purged with clean air for 40 minutes. The temperature of the clean air is 60℃, the humidity is less than 20%, and the outlet flow rate is greater than 4m / s. S7, Baking: The radiator is conveyed to the hot air baking mechanism 17 of the surface sealing treatment equipment 1 and baked at 95°C for 5 hours after the drying treatment in step 5.

[0047] Pickling solution: 1.8% anionic surfactant, 1.2% nonionic surfactant, and 6.5% hydrofluoric acid are added to an appropriate amount of pure water, stirred and mixed evenly, and then made up to 100% with pure water.

[0048] Sealing solution: 0.6% by mass of organic titanate complex and 0.9% zirconium nitrate are added to an appropriate amount of deionized water, stirred until completely dissolved, and then made up to 100% with deionized water.

[0049] Microscopic analysis as follows Figures 11-13 As shown, through microscopic analysis of the aluminum surface, especially the weld seam, it can be found that the process significantly improves the surface microstructure of the aluminum. Before the process, the surface of the radiator weld seam had residual oxide crystals, the surface was relatively rough, and there were a lot of cracks. After the process, the crystals on the surface of the radiator weld seam disappeared, the weld seam became smoother, and the cracks were significantly reduced and narrowed.

[0050] Performance of the treated radiator For room temperature immersion, pure water with a conductivity of <1μS / cm is poured into the water tank, the tube is sealed and left at room temperature for 24 hours, then poured out in multiple portions, and the conductivity of the water is measured and the average value is taken.

[0051] For high-temperature immersion, pure water with a conductivity of <1μS / cm is poured into the water tank, the pipe is sealed, and the tank is placed in an oven at 85-90℃ for 24 hours. The water is then poured out in multiple batches, and the conductivity of the water is measured and the average value is taken.

[0052] The experimental results are shown in the table.

[0053] The surface sealing treatment of the radiator significantly improves the cleanliness of the water tank, reduces the level of ion precipitation, and does not affect cleanliness during short-term storage, demonstrating good tolerance to high-temperature environments.

Claims

1. A method for sealing the surface of a radiator, characterized in that, Includes the following steps: S1, Pickling: Place the radiator with its inlet and outlet facing upwards, and transport it to the pickling area (11) via the roller conveyor line of the surface sealing treatment equipment (1). Heat the pickling solution to 60-70℃ and then circulate and rinse the inner flow channel of the radiator for 5-15 minutes. S2, First pure water rinse: The radiator is transported to the first rinsing zone (12) of the surface sealing treatment equipment (1). Pure water with an ion concentration of less than 1µS / cm is heated to 60-70℃, and then the radiator after step (1) is circulated and rinsed for 30-50 minutes. S3, Surface sealing treatment: The radiator is transported to the surface sealing treatment area (13) of the surface sealing treatment equipment (1), and the radiator after rinsing in step (2) is circulated and rinsed for 5-15 minutes at room temperature using sealing treatment liquid; S4, Second pure water rinse: The radiator is transported to the second rinsing zone (14) of the surface sealing treatment equipment (1), and the radiator after step (3) is rinsed for 15-25 minutes at room temperature with pure water with an ion concentration of less than 1µS / cm. S5, Hot water treatment: The radiator is transported to the hot water zone (15) of the surface sealing treatment equipment (1), and the radiator after rinsing in step (4) is rinsed for 25-35 minutes at 90-100℃ using pure water with an ion concentration of less than 1µS / cm. S6, Drying: The radiator is transported to the drying zone (16) of the surface sealing treatment equipment (1), and the radiator after hot water treatment in step (5) is purged with clean air for 20-40 minutes. The temperature of the clean air is 50-60℃, the humidity is less than 20%, and the outlet flow rate is greater than 4m / s. S7, Baking: The radiator is conveyed to the hot air baking mechanism (17) of the surface sealing treatment equipment (1) and the radiator after drying in step (5) is baked at 85-95℃ for 3-5 hours.

2. The method for sealing the surface of a radiator according to claim 1, characterized in that, The pickling solution comprises, by mass percentage: 1-2% anionic surfactant, 1-2% nonionic surfactant, 3-7% hydrofluoric acid, with the remainder being pure water; the sealing treatment solution comprises, by mass percentage: less than 1.0% organic compounds, less than 1.4% nitrates, with the remainder being deionized water.

3. The method for sealing the surface of a radiator according to claim 1, characterized in that, The surface sealing treatment equipment (1) includes a frame (18) and a roller conveyor line (19). The frame is provided with pickling area (11), first rinsing area (12), surface sealing treatment area (13), second rinsing area (14), hot water area (15), and drying area (16) from left to right. The roller conveyor line (19) runs through the above areas. A hot air baking mechanism (17) is also provided on the right side of the drying area (16).

4. The method for sealing the surface of a radiator according to claim 1, characterized in that, The pickling zone (11), the first rinsing zone (12), the surface sealing treatment zone (13), the second rinsing zone (14), and the hot water zone (15) all include a liquid storage tank (161), an automatic docking and disengagement structure (162), and a radiator positioning structure (20). The roller conveyor line (19) is located above the liquid storage tank (161). The radiator positioning structure (20) is symmetrically arranged on both sides of the roller conveyor line (19) in the direction of travel, and is used to center or clamp the radiator from both sides when it arrives at the work station. The automatic docking and disengagement structure (162) is located above the roller conveyor line (19).

5. A method for sealing the surface of a radiator according to claim 4, characterized in that, The automatic docking and disengagement structure (162) includes a fluid input pipe (1621), a fluid output pipe (1622), a connecting plate (1623), and an electric telescopic rod (1624). The fluid input pipe (1621) and the fluid output pipe (1622) are mounted on the connecting plate (1623). The motor end of the electric telescopic rod (1624) is mounted on the frame (18). The push rod end of the electric telescopic rod (1624) is fixedly connected to the connecting plate (1623). The fluid input pipe (1621) is connected to the output port of the liquid storage tank (161). The fluid output pipe (1622) is connected to the input port of the liquid storage tank (161) via a pump.

6. The method for sealing the surface of a radiator according to claim 5, characterized in that, Both the fluid input pipe (1621) and the fluid output pipe (1622) include a pipe body (1626) and a pneumatic sealing ring (1627), with the pneumatic sealing ring (1627) surrounding the bottom of the pipe body (1626).

7. The method for sealing the surface of a radiator according to claim 4, characterized in that, The radiator positioning structure (20) includes a linear drive device (201), a positioning force transmission plate (202), and an adaptive V-shaped positioning head (203). The linear drive device (201) is fixed on the frame (18). The positioning force transmission plate (202) is connected to the output end of the linear drive device (201). The bottom of the adaptive V-shaped positioning head (203) is provided with a pivot shaft (204). The pivot shaft (204) cooperates with the shaft hole opened at the end of the positioning force transmission plate (202) to form a rotatable connection. An elastic reset member (205) that provides a reset torque is sleeved on the pivot shaft (204).

8. The method for sealing the surface of a radiator according to claim 4, characterized in that, The hot air baking mechanism (17) includes a rotary motor (172), a polygonal baking drum (173), a drum spindle (174), an internal conveyor belt (174), a material separating unit (177), and a sealing cover plate (178). The polygonal baking drum (173) is supported between the frame (18) by the drum spindle (174). The drum spindle (174) and the rotary motor (172) are connected by gear meshing. The rotary motor (172) drives the entire baking drum to rotate around its axis. Multiple material separating units (177) are evenly arranged circumferentially on the inner side wall of the polygonal baking drum (173). The internal conveyor belt (174) is laid in each material separating unit (177). The internal conveyor belt (174) is used to receive the radiator conveyed from the drum conveyor line (19). The sealing cover plate (178) covers the opening of the material separating unit (177) to form a closed baking chamber.

9. A method for sealing the surface of a radiator according to claim 8, characterized in that, The inside of the roller spindle (174) is a cavity, with an open end on the right and a closed end on the left. Sealed bearings (30) are fixed to both ends of the roller spindle (174) and are fixed to the frame (18). The inner ring of the sealed bearing (30) is fixedly connected to the outer wall of the roller spindle (174). A hot air inlet pipe (31) is fixed to the outer ring of the sealed bearing (30) on the right side of the roller spindle (174), and a return air inlet pipe (32) is fixed to the outer ring of the sealed bearing (30) on the left side of the roller spindle (174). The right end of the pipe (32) is a closed end. The side wall of the return air inlet pipe (32) is provided with a return air pipe (33). The roller main shaft (174) is divided into a non-conductive air inlet section (34) and an air outlet section (35). The air inlet section (34) of the roller main shaft (174) is provided with several radially extending air outlet pipes (36) in the area of ​​the material separation unit (177). Each material separation unit (177) corresponds to one air outlet pipe (36). The air outlet section (35) is provided with a return air port (351). The return air port (351) and the side wall of the material separation unit (177) are connected by a pipe.

10. A method for sealing the surface of a radiator according to claim 9, characterized in that, The internal conveyor belt (174) is a grid conveyor belt.

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