Cleaning method and system applied to manufacturing, mounting and series washing stages of cooling circulation pipe network of electronic equipment

Abstract

The invention discloses a cleaning method applied to manufacturing, mounting and series washing stages of a cooling circulation pipe network of electronic equipment. The cleaning method comprises the steps that cooling system equipment is cleaned, internal impurities in a pipeline are removed, then the pipeline is blocked, and after a valve and a pipe fitting are cleaned, ports and sealing faces of the valve and the pipe fitting are protected; the method comprises the following steps: prefabricating a pipeline on a prefabricating site, and cleaning the prefabricated pipeline, which sequentially comprises chemical oil removal, hot water rinsing, acid pickling, clear water flushing, passivation, hot water flushing, drying and maintenance; in the pipeline installation process, the surfaces and the interiors of the pipeline, the valve and the pipe fitting are cleaned before the pipeline is installed, and the inner surfaces of the pipeline and the valve are cleaned before the pipe joint is connected; and in the pipe network series washing process, cleaning liquid, fresh water and deionized water are sequentially adopted for cleaning the installed cooling circulation pipe network in a grading mode, and nitrogen blowing is conducted. According to the method, the problems that the cooling circulation pipe network of the electronic equipment is not thoroughly cleaned, and the cleaning cleanliness cannot meet the requirement can be solved.

Description

Technical Field

[0001] This invention relates to the field of cooling protection technology, specifically to a cleaning method and system applied to the manufacturing, installation, and rinsing stages of cooling circulation networks for electronic devices. Background Technology

[0002] To ensure ease of commissioning, installation, and use, electronic equipment extensively utilizes quick-connect couplings. Simultaneously, to guarantee the heat exchange efficiency of the electronic equipment's cooling backplate, narrow-channel heat exchangers are widely employed. To ensure the safety of electronic equipment, the cooling circulation network requires high filtration accuracy. Before being put into use, the entire cooling circulation network must achieve a cleanliness level of Class VIII after cleaning (referencing "GJB420b-2006 Classification of Solid Contamination in Aviation Working Fluids"). Therefore, a series of specific methods must be employed during the manufacturing, installation, and queuing processes of the cooling circulation network to reduce contaminant retention levels during manufacturing, prevent the introduction of new contaminants during installation, and rapidly achieve the Class VIII cleanliness requirement during queuing. Traditional cleaning methods sometimes result in incomplete cleaning of equipment or accessories, failing to meet cleanliness requirements. Therefore, a complete cleaning process must be developed. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a cleaning method and system for the manufacturing, installation and series cleaning stages of cooling circulation pipe networks of electronic devices, which addresses the shortcomings of the prior art. This method can solve the problems of incomplete cleaning and insufficient cleaning cleanliness of cooling circulation pipe networks of electronic devices.

[0004] To achieve the above objectives, according to one aspect of the present invention, a cleaning method is provided for the manufacturing, installation, and flushing stages of a cooling circulation network for electronic devices, wherein the cooling medium in the cooling circulation network is a special electronic device coolant, and the cleaning method includes: The cooling system equipment is cleaned, the pipes are sealed after removing internal debris, and the valves and fittings are cleaned and then the ports and sealing surfaces of the valves and fittings are protected. Pipes are prefabricated on the prefabrication site, and the prefabricated pipes are cleaned in sequence, including chemical degreasing, hot water rinsing, pickling, water rinsing, passivation, hot water rinsing, drying and maintenance. During pipeline installation, the surfaces and interiors of the pipeline, valves, and fittings are cleaned before installation, and the inner surfaces of the pipeline and valves are cleaned before connecting pipe joints to remove impurities and foreign objects. During the pipeline flushing process, the installed cooling circulation pipeline is cleaned in stages using cleaning fluid, fresh water, and deionized water, and then purged with nitrogen.

[0005] In the above scheme, the pipeline is a channel for conveying the coolant of the special electronic equipment; the valve is a device for controlling, regulating or cutting off the flow of the coolant of the special electronic equipment; the pipe fitting is an auxiliary component of the pipeline for connecting, branching, turning or changing diameter. The coolant for the special electronic equipment includes 60# coolant and 65# coolant.

[0006] In the above scheme, the cleaning of the prefabricated pipes includes: The chemical degreasing includes: scrubbing pipes with oil stains on their surface with diesel or water-based detergent before chemical degreasing; and using mechanical methods to remove scale from pipes with severe oil stains. The chemical degreasing is carried out by immersion in a tank, in which the surface of the pipe is completely submerged to avoid air remaining in the pipe. During the immersion process, the solution in the inner cavity of the chemical degreasing tank is continuously replaced. The hot water rinsing includes: immersing the pipe in a water tank with a water temperature of about 75~85℃ for 3 to 5 minutes, wherein the water in the tank is in a flowing state. The pickling process includes: using an ultrasonic cleaner for pickling, with the pickling solution level covering the top of the pipe; the pickling passivation time depends on the degree of oxide layer removal, and the pickling is completed when the rust or oxide scale on the pipe surface is loose and can be easily wiped off; the pickling solution is a conventional mixed pickling solution, including a mixture of 120-150 g / L nitric acid and 30 g / L hydrofluoric acid. The water rinsing includes: using a mixed flow of compressed air and water to spray and wash the surface of the pipe to remove surface contaminants after acid washing; The passivation process includes: immersion in a tank to passivate the pipe, ensuring that air remains inside the pipe during immersion, and continuously replacing the passivation solution. After passivation, a uniform dark gray-white oxide film should form on the pipe surface. A white cloth should be passed through the inner wall of the pipe, and no welding slag, oxide scale, or other impurities should adhere to the pipe or weld joints, and no rust or oil stains should be present. The passivation solution is a mixture of acid and water, including one of a first solution and a second solution. The first solution is a mixture of 1 part by mass of 65%-68% nitric acid and 4 parts by mass of pure water, and the second solution is a mixture of 2 parts by mass of 65%-68% nitric acid, 1 part by mass of 10% hydrofluoric acid, and 7 parts by mass of pure water. The hot water rinsing includes rinsing with hot water at a temperature of 75~85℃, and after rinsing, the residual hot water solution after rinsing should be neutral when checked with pH test paper. The drying and maintenance include: drying the cleaned pipes with clean compressed air, sealing the openings, and storing them in a clean and dry place.

[0007] In the above scheme, the installed cooling circulation network is cleaned in stages using cleaning fluid, fresh water, and deionized water in sequence: The cleaning process includes: cleaning the installed cooling circulation pipe network with a special stainless steel pipe cleaning solution; mixing the special stainless steel pipe cleaning solution with fresh water to fill the pipe system with the cleaning solution; circulating the cleaning solution to 60-80°C through the system's self-circulation operation for at least 12 hours; during the cleaning process, all valves inside the pipes should be fully open to ensure the cleaning solution reaches every section of the pipe and cleans every part; simultaneously, the pipes should be continuously tapped with a wooden hammer, paying attention to welds, dead corners, bends, and the bottom of the pipes, without damaging the pipes; after cleaning, drain the water at the lowest point of the system to ensure that the cleaning solution and impurities are completely removed; the special stainless steel pipe cleaning solution includes CLF-700 and 3M stainless steel cleaning solution. The cleaning fluid cleaning also includes cleaning the pipeline filter screen, cleaning the filtered impurities, and checking whether the filter screen is intact and secure. Freshwater cleaning includes: repeatedly flushing the installed cooling circulation pipe network system with fresh water for no less than 12 hours, and changing the water no less than 3 times; during the water change process, inspecting the pipe filters, cleaning the filtered impurities, and checking whether the filter screen is intact and secure; after freshwater cleaning, the water color and transparency at the pipe outlet and inlet should be consistent; inspecting the pipe filters, there should be no particulate matter on the filter screen; the inner wall of the pipe should be smooth and clean, appearing dark grayish-white, without any metal particles or other impurities attached; Deionized water cleaning includes: flushing the installed cooling circulation pipe network system with deionized water for a circulation time of not less than 3 hours. After cleaning, check that the chloride ion content in the deionized water in the pipes does not exceed 100 mg / L. If the chloride ion content in the deionized water exceeds the standard, the entire system should be drained and refilled with deionized water for a second flush until the requirements are met. Nitrogen purging includes: using high-pressure nitrogen to purge the pipeline to remove residual deionized water; purging in the order of main pipe and branch pipes, with branch pipe valves closed when purging the main pipe, and branch pipe purging starting from the first branch pipe in the direction of the cooling medium flow; after the pipeline purging is completed, inspection and confirmation should be carried out according to the inspection requirements, and a record should be made. Except for the specified inspection, no other work that may affect the cleanliness of the pipeline should be carried out, and the pipeline joints should be sealed.

[0008] In the above scheme, the specifications of the nitrogen used for purging are: particle size: ≤3μm, dew point: -65℃, purity: ≥99.9%.

[0009] In the above scheme, the indicators of the deionized water are: pH (25℃): 5.5~8, Cl...- ≤1mg / L, Fl - : ≤1mg / L, S 2- : ≤1mg / L, conductivity (25℃): ≤3us / cm, SiO2: ≤0.1mg / L.

[0010] In the above solution, cleaning the cooling system equipment includes: removing welding slag, particulate matter, etc. from inside the equipment, draining accumulated water to keep the inside dry, and sealing the external pipe interfaces after inspection and confirmation. The cooling system equipment includes a circulating water pump, a plate heat exchanger, a constant pressure water supply device, and a water distribution manifold. After removing internal debris from the pipeline, sealing it includes: after inspecting and confirming that there is no debris inside the pipeline, sealing it with a pipe cap or other sealing method; reinforcing any loose seals to ensure that dust, debris, rainwater, etc., cannot enter the pipeline. For pipes with missing seals, conduct an internal inspection, and remove any internal debris before resealing. The ports and sealing surfaces of the valves and pipe fittings are protected by installing flange covers or plugs.

[0011] In the above scheme, the prefabrication site includes a steel platform or a hardened ground; the prefabrication site should be cleaned daily to keep it clean and orderly. The prefabrication of the pipeline includes: stainless steel pipes used in the cooling circulation network of electronic equipment; the stainless steel pipes are cut using a saw or profile cutting machine during the cutting and welding process; before welding the joints, debris near the pipe openings should be cleaned; the stainless steel pipes are welded using manual tungsten inert gas (TIG) welding, and pipes with a diameter greater than DN200 are welded using CO2 automatic shielded welding; after the pipeline welding is completed, the slag, flux powder, and welding spatter inside and outside the pipeline are removed, the weld is repaired and cleaned, and the inner wall of the pipeline is blown with compressed air to ensure the pipeline is clean; the inert shielding gas used in the manual TIG welding includes argon and nitrogen.

[0012] In the above scheme, before the pipeline installation process, the surface and interior of the pipeline, valve and fittings should be cleaned of sand, iron filings, slag and other debris; the seals of the prefabricated pipe sections to be handed over should be opened and their internal cleanliness should be checked and confirmed again. The connection methods of the connecting pipe joint include welding connection, threaded connection, and flange connection; wherein the threaded connection adopts the PTFE gasket sealing method; when the flange connection is used, a PTFE gasket is used, the diameter of the PTFE gasket is the same as the flange diameter, and the PTFE gasket is fitted with drilled holes, the number and size of which refer to the bolt holes on the flange. The flange bolts should be tightened in a diagonal sequence, and a torque wrench should be used to ensure that the preload of each bolt is consistent. During pipeline installation, open sections should be sealed during construction interruptions to prevent debris from entering the pipe. Before resuming installation, the inside of the pipe must be checked and confirmed to be clean.

[0013] According to another aspect of the present invention, a cleaning system is provided for use in the manufacturing, installation, and rinsing stages of a cooling circulation network for electronic devices, wherein the cooling medium in the cooling circulation network is a special electronic device coolant, and the cleaning system includes: The pipe fitting cleaning module is used to clean cooling system equipment, remove internal debris from pipes and then seal them, and clean valves and fittings and then protect the ports and sealing surfaces of the valves and fittings. The prefabrication cleaning module is used to prefabricate pipes on the prefabrication site and clean the prefabricated pipes, including chemical degreasing, hot water rinsing, acid washing, clean water rinsing, passivation, hot water rinsing, drying and maintenance. The pipeline installation and cleaning module is used to clean the surface and interior of the pipeline, valve, and fittings before pipeline installation, and to clean the inner surface of the pipeline and valve before connecting pipe joints. The pipeline flushing module is used to sequentially clean the installed cooling circulation pipeline with cleaning fluid, fresh water, and deionized water during the pipeline flushing process, and to purge with nitrogen.

[0014] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: (1) The present invention provides a cleaning method for the manufacturing, installation and series cleaning stages of cooling circulation pipe network of electronic equipment. This method can solve the problem of incomplete cleaning of cooling circulation pipe network of electronic equipment and failure to meet the cleaning requirements. Attached Figure Description

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic flowchart of a cleaning method applied to the manufacturing, installation, and series cleaning stages of a cooling circulation network for electronic devices, as described in Embodiment 1 of the present invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0017] It should be understood that the sequence number of each step in the embodiment does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0018] Example 1 This application provides a cleaning method for the manufacturing, installation, and flushing stages of cooling circulation networks for electronic devices. In this embodiment, the cooling medium in the cooling circulation network is a specialized electronic device coolant. Please refer to [link to relevant documentation]. Figure 1 The cleaning method includes: S1. Clean the cooling system equipment, remove internal debris from the pipes and then seal them, and clean the valves and fittings before protecting the ports and sealing surfaces of the valves and fittings.

[0019] Specifically, in this embodiment, it can be understood that the cooling medium in the cooling circulation network of the electronic equipment is a special electronic equipment coolant (specifically, 60# coolant and 65# coolant in this embodiment), which has a certain degree of metal corrosivity and penetrability, and requires high cleaning results, which need to reach level eight cleanliness.

[0020] In this embodiment, the cooling circulation network for electronic devices includes pipes, valves, and fittings. Pipes are channels for transporting coolant to the specialized electronic devices; valves are devices used to control, regulate, or cut off the flow of coolant; and fittings are auxiliary components for connecting, branching, turning, or changing the diameter of the pipes. This step outlines installation and cleaning requirements for the equipment, pipes, and accessories (valve and fittings) within the cooling system to ensure that the amount of source contaminants in the cooling system is kept at a low level.

[0021] Specifically, in this embodiment, the cleaning method for the equipment, pipes, and accessories within the cooling system is as follows: S11, Equipment level: All equipment in the cooling system (circulating water pump, plate heat exchanger, constant pressure water supply device, water distribution manifold, etc.) should be cleaned before leaving the factory to remove welding slag, particulate matter, etc. from the inside of the equipment, drain the accumulated water and keep the inside dry, and seal the external pipe interfaces after inspection and confirmation. S12, Pipeline level: After the delivered pipeline is inspected and confirmed to be free of debris, it should be sealed with a pipe cap or other sealing method. Loose seals should be reinforced to ensure that dust, debris, rainwater, etc. cannot enter the pipeline. For pipes with missing seals, internal inspection should be carried out, and debris inside should be removed before resealing. S13, Valve and Fittings Level: (1) Valves and fittings should be cleaned before leaving the factory to remove welding slag, particulate matter, etc. inside the equipment, drain the accumulated water and keep the inside dry. After inspection and confirmation, flange covers or plugs should be installed on the valve and fitting ports and sealing surfaces for protection. (2) When inspecting valves and fittings upon receipt, visually inspect the inner surface of the valves and fittings for burrs, flash, and other debris. If any are found, they must be removed. (3) Valves and fittings should be properly stored after unpacking and should not be stored in places with standing water; small valves and fittings should be stored on hardened indoor floors or placed on shelves after unpacking. (4) If water or debris accumulates inside valves and fittings, they should be carefully inspected, the water and debris removed, and after drying, they should be properly stored again.

[0022] S2 involves prefabricating pipes at the prefabrication site and cleaning the prefabricated pipes, including chemical degreasing, hot water rinsing, acid washing, clean water rinsing, passivation, hot water rinsing, drying, and maintenance.

[0023] Specifically, in this embodiment, 316L stainless steel pipes are used in the cooling circulation network for electronic equipment. The pipes are prefabricated on a steel platform or a hardened surface. The prefabrication site should be cleaned daily to maintain cleanliness and order. During cutting and welding, the stainless steel pipes are cut using a saw or profile cutting machine. Before welding the joints, debris near the pipe openings should be thoroughly cleaned. The stainless steel pipes are welded using manual tungsten inert gas (TIG) welding (argon is used as the inert shielding gas in this embodiment). Pipes with a diameter greater than DN200 are welded using automatic carbon dioxide shielded welding. After welding, slag, flux powder, and welding spatter are removed from both inside and outside the pipes. The weld seams are repaired and cleaned, and the inner wall of the pipes is purged with compressed air to ensure cleanliness.

[0024] In this embodiment, the prefabricated pipeline is cleaned, including chemical degreasing, hot water rinsing, acid washing, clean water rinsing, passivation, hot water rinsing, drying, and maintenance, to remove grease, scale, rust, and other deposits from the pipeline surface. The cleaning process should be carried out according to the following steps: (1) Preparation and chemical degreasing For pipes with oil stains on the surface, they are first wiped with diesel oil before chemical degreasing. For pipes with severe oil stains, mechanical methods are used for descaling. Chemical degreasing is carried out by immersion in a tank, with the pipe surface completely submerged to avoid air retention in the pipe. During the immersion process, the chemical degreasing solution in the inner cavity (in this embodiment, it is an alkaline degreasing agent) is continuously replaced.

[0025] (2) Rinse with hot water Immerse the pipes in a water tank at around 80°C for 3 to 5 minutes, ensuring the water is constantly flowing and refreshed.

[0026] (3) Pickling Precast pipes should be acid-washed using an ultrasonic cleaner. The acid-washing solution (specifically, a mixture of 120-150 g / L nitric acid and 30 g / L hydrofluoric acid in this embodiment) should cover the top of the pipe fittings. The acid-washing passivation time depends on the degree of oxide layer removal. Acid washing is complete when the rust or oxide scale on the pipe surface is loose and can be easily wiped off.

[0027] (4) Rinse with clean water When rinsing with clean water, the water flow has appropriate impact force. A mixture of compressed air and water is used to spray and clean the surface of the pipe to remove surface dirt after acid washing.

[0028] (5) Passivation Passivation is performed by immersion in a tank. During immersion, air should be avoided from remaining in the pipe. The passivation solution used in the inner cavity (in this embodiment, a solution prepared with 20% nitric acid (concentration 65%-68%) + 80% pure water) should be changed continuously. After passivation, a uniform dark gray-white oxide film should form on the surface of the pipe. The inside of the pipe and the welded joints should be inspected with a white cloth through the inner wall. There should be no weld slag, oxide scale, or other impurities adhering to the pipe, and no rust or oil stains.

[0029] (6) Rinse with hot water After the pipeline has been pickled and passivated, it should be rinsed with hot water at 80°C. After rinsing, the residual hot water should be neutral, as checked with pH paper.

[0030] (7) Drying and maintenance The cleaned pipes are dried with clean compressed air, sealed, and stored in a clean and dry place.

[0031] S3. During pipeline installation, clean the surface and interior of the pipeline, valves, and fittings before installation, and clean the inner surface of the pipeline and valves before connecting pipe joints to remove impurities and foreign objects.

[0032] Specifically, in this embodiment, it is understood that before the pipeline installation process, sand, iron filings, slag, and other debris should be removed from the surface and interior of each pipe, valve, and fitting. For prefabricated pipe sections being handed over, the seals should be opened, and their internal cleanliness should be checked and confirmed again. In particular, in principle, openings in the pipeline should be completed during the pipeline prefabrication stage; opening operations are not allowed on the installation site. When it is necessary to open holes in an already installed pipeline, any debris generated during cutting should be thoroughly cleaned from the inside of the pipe. During on-site installation, before connecting any pipe joints, the inner surfaces of the components (pipes, valves) should be cleaned to remove all impurities and foreign objects. The connection methods for connecting pipe joints include welding, threaded connections, and flange connections, with specific requirements as follows: (1) When using threaded connections, gaskets (PTFE) must be used for sealing. Solid or liquid threaded packing is strictly prohibited to prevent the packing from entering the pipeline system.

[0033] (2) When connecting flanges, use polytetrafluoroethylene gaskets with the same diameter as the flange. Drill holes in the gaskets, and refer to the bolt holes on the flange for the number and size. Tighten the flange bolts in a diagonal order and use a torque wrench to ensure that the preload of each bolt is consistent.

[0034] (3) When the pipeline installation is interrupted, the open parts must be sealed to prevent debris from entering the pipe. When the installation is restarted, the inside of the pipeline must be checked and confirmed to be clean before construction can begin.

[0035] S4. During the pipeline flushing process, the installed cooling circulation pipeline is cleaned in stages using cleaning fluid, fresh water, and deionized water, and nitrogen is purged.

[0036] Specifically, in this embodiment, a circulating cleaning process is used for the installed cooling circulation network, including sequential cleaning with cleaning fluid, fresh water, and deionized water, as well as equipment fine filters, so that the entire network can quickly reach the requirements of level eight cleanliness (referring to "Classification of Solid Contamination of Aviation Working Fluids" in GJB420b-2006) after different levels of cleaning. The pipeline water pressure test medium should preferably be clean fresh water. Before the water pressure test, a filter with a 40μm precision should be installed at the water inlet to prevent the introduction of particulate matter and impurities during water intake. Before cleaning the pipeline, all supply and return water inlets at the end of the system should be short-connected using flexible metal hoses (316L stainless steel) to form a loop. The flexible metal hoses must be cleaned and inspected before use to ensure that there are no impurities or particulate matter inside.

[0037] In this embodiment, the installed cooling circulation network is cleaned in stages using cleaning fluid, fresh water, and deionized water, as follows: (1) Cleaning with cleaning solution Cleaning is performed using a special cleaning solution for stainless steel pipes (CLF-700 in this example). The system is filled with the cleaning solution according to the mixing ratio of the special cleaning solution and fresh water (diluted to 5% in this example). The system is then circulated, with the cleaning solution heated to 60-80°C for at least 12 hours. During the cleaning process, all valves inside the pipes should be fully open to ensure the cleaning solution reaches every section of the pipe and cleans every area. Simultaneously, the pipes should be continuously tapped with a wooden hammer, paying particular attention to welds, corners, bends, and the bottom of the pipes, without damaging the pipes. After cleaning, drain the system at its lowest point to ensure that the cleaning solution and impurities are completely removed. Clean the pipe filter screen, removing any filtered impurities, and check that the filter screen is intact and secure.

[0038] (2) Fresh water rinsing The entire system should be repeatedly flushed with fresh water for at least 12 hours, with at least 3 water changes. During the water changes, inspect the pipeline filters, clean out any filtered impurities, and check that the filter screens are intact and secure. After fresh water flushing, visually inspect the color and transparency of the water at the outlet. The color and transparency of the water at the inlet and outlet of the flushed pipeline should be consistent. Inspect the pipeline filters; the filter screens should be free of particles. The inner walls of the pipelines should be smooth, clean, and dark grayish-white, free of metallic particles or other impurities.

[0039] (3) Cleaning with deionized water The entire system should be flushed with deionized water for at least 3 hours. After flushing, the chloride ion content in the deionized water should not exceed 100 mg / L. If the chloride ion content exceeds the standard, the entire system should be drained and refilled with deionized water for a second flush until the requirement is met.

[0040] The main indicators of deionized water are as follows: pH (25℃): 5.5~8; Cl - : ≤1mg / L; Fl - : ≤1mg / L; S 2- : ≤1mg / L; Electrical conductivity (25℃): ≤3µs / cm; SiO2: ≤0.1mg / L.

[0041] (4) Nitrogen purging After deionized water cleaning, the pipeline is purged with high-pressure nitrogen to completely remove any residual deionized water. Purging should proceed in the order of main pipe and branch pipes. When purging the main pipe, the branch pipe valves should be closed. Branch pipe purging should begin with the first branch pipe in the direction of the cooling medium's flow. After purging, the pipeline is inspected and confirmed according to inspection requirements, and a record is made. Except for the specified inspection, no other work that may affect the cleanliness of the pipeline should be carried out, and the pipeline joints should be sealed. The main specifications of the nitrogen used for purging are as follows: Particle size: ≤3μm; Dew point: -65℃; Purity: ≥99.9%.

[0042] In summary, this embodiment provides a cleaning method for the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices. This method can solve the problems of incomplete cleaning and insufficient cleanliness of cooling circulation pipe networks for electronic devices.

[0043] Example 2 This application provides a cleaning method for the manufacturing, installation, and flushing stages of cooling circulation pipe networks in electronic devices. The method in this embodiment is basically the same as the method in Embodiment 1, except that: When stainless steel pipes are welded using manual tungsten inert gas welding, the inert shielding gas is nitrogen. For pipes with oily surfaces, first wipe them with a water-based detergent before chemical degreasing; During the pipeline flushing process, the cleaning fluid used is 3M stainless steel cleaning fluid.

[0044] Another embodiment of this application provides a cleaning system applied to the manufacturing, installation, and rinsing stages of cooling circulation networks for electronic devices, comprising: The pipe fitting cleaning module is used to clean cooling system equipment, remove internal debris from pipes and then seal them, and clean valves and fittings and then protect the ports and sealing surfaces of valves and fittings. The prefabrication cleaning module is used to prefabricate pipes on the prefabrication site and clean the prefabricated pipes, including chemical degreasing, hot water rinsing, acid washing, clean water rinsing, passivation, hot water rinsing, drying and maintenance. The pipeline installation and cleaning module is used to clean the surface and interior of pipes, valves, and fittings before installation, and to clean the inner surface of pipes and valves before connecting pipe joints. The pipeline flushing module is used to sequentially clean the installed cooling circulation pipeline with cleaning fluid, fresh water, and deionized water during the pipeline flushing process, and to purge with nitrogen.

[0045] It should be noted that, depending on the implementation needs, the various steps described in this application can be broken down into more steps, or two or more steps or parts of the steps can be combined into new steps to achieve the purpose of this invention.

[0046] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cleaning method applied to the manufacturing, installation, and flushing stages of cooling circulation pipe networks for electronic devices, characterized in that, The cooling medium in the cooling circulation network of the electronic equipment is a special electronic equipment coolant. The cleaning method includes: The cooling system equipment is cleaned, the pipes are sealed after removing internal debris, and the valves and fittings are cleaned and then the ports and sealing surfaces of the valves and fittings are protected. Pipes are prefabricated on the prefabrication site, and the prefabricated pipes are cleaned in sequence, including chemical degreasing, hot water rinsing, pickling, water rinsing, passivation, hot water rinsing, drying and maintenance. During pipeline installation, the surfaces and interiors of the pipeline, valves, and fittings are cleaned before installation, and the inner surfaces of the pipeline and valves are cleaned before connecting pipe joints. During the pipeline flushing process, the installed cooling circulation pipeline is cleaned in stages using cleaning fluid, fresh water, and deionized water, and then purged with nitrogen.

2. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The pipeline is a channel for conveying the coolant of the special electronic equipment; the valve is a device for controlling, regulating, or cutting off the flow of the coolant of the special electronic equipment; the pipe fitting is an auxiliary component of the pipeline for connecting, branching, turning, or changing diameter. The coolant for the special electronic equipment includes 60# coolant and 65# coolant.

3. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The process of cleaning the prefabricated pipes is as follows: The chemical degreasing includes: scrubbing the pipes with oil stains on the surface with diesel or water-based detergent before chemical degreasing; and using mechanical methods to remove scale from pipes with severe oil stains. The chemical degreasing is carried out by immersion in a tank, in which the surface of the pipes is completely submerged, and the solution in the inner cavity of the chemical degreasing tank is continuously replaced during the immersion process. The hot water rinsing includes: immersing the pipe in a water tank with a water temperature of 75~85℃ for 3 to 5 minutes, wherein the water in the tank is in a flowing state; The pickling process includes: using an ultrasonic cleaner for pickling, with the pickling solution level covering the top of the pipe; the pickling passivation time depends on the degree of oxide layer removal, and the pickling is completed when the rust or oxide scale on the pipe surface is loose and can be easily wiped off; wherein the pickling solution includes a mixture of 120-150 g / L nitric acid and 30 g / L hydrofluoric acid. The water rinsing includes: using a mixed flow of compressed air and water to spray and wash the surface of the pipe to remove the surface contaminants after acid washing; The passivation process includes: immersion in a tank to passivate the pipe, ensuring that air remains inside the pipe during immersion, and continuously replacing the passivation solution. After passivation, a uniform dark gray-white oxide film should form on the pipe surface. A white cloth should be passed through the inner wall of the pipe, and no welding slag, oxide scale, or other impurities should adhere to the pipe or weld joints, and no rust or oil stains should be present. The passivation solution is a mixture of acid and water, including one of a first solution and a second solution. The first solution is a mixture of 1 part by mass of 65%-68% nitric acid and 4 parts by mass of pure water, and the second solution is a mixture of 2 parts by mass of 65%-68% nitric acid, 1 part by mass of 10% hydrofluoric acid, and 7 parts by mass of pure water. The hot water rinsing includes rinsing with hot water at a temperature of 75~85℃, and after rinsing, the residual hot water solution after rinsing should be neutral when checked with pH test paper. The drying and maintenance include: drying the cleaned pipes with clean compressed air, sealing the openings, and storing them in a clean and dry place.

4. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The installed cooling circulation network is then cleaned in stages using cleaning fluid, fresh water, and deionized water in a tiered manner. The cleaning process includes: cleaning the installed cooling circulation pipe network with a special stainless steel pipe cleaning solution; mixing the special stainless steel pipe cleaning solution with fresh water to fill the pipe system with the cleaning solution; circulating the cleaning solution to 60-80°C through the system's self-circulation operation for at least 12 hours; during the cleaning process, all valves inside the pipes should be fully open to ensure the cleaning solution reaches every section of the pipe and cleans every part; simultaneously, the pipes should be continuously tapped with a wooden hammer, paying attention to welds, dead corners, bends, and the bottom of the pipes, without damaging the pipes; after cleaning, drain the water at the lowest point of the system to ensure that the cleaning solution and impurities are completely removed; the special stainless steel pipe cleaning solution includes CLF-700 and 3M stainless steel cleaning solution. The cleaning fluid cleaning also includes cleaning the pipeline filter screen, cleaning the filtered impurities, and checking whether the filter screen is intact and secure. Freshwater cleaning includes: repeatedly flushing the installed cooling circulation pipe network system with fresh water for no less than 12 hours, and changing the water no less than 3 times; during the water change process, inspecting the pipe filters, cleaning the filtered impurities, and checking whether the filter screen is intact and secure; after freshwater cleaning, the water color and transparency at the pipe outlet and inlet should be consistent; inspecting the pipe filters, there should be no particulate matter on the filter screen; the inner wall of the pipe should be smooth and clean, appearing dark grayish-white, without any metal particles or other impurities attached; Deionized water cleaning includes: flushing the installed cooling circulation pipe network system with deionized water for a circulation time of not less than 3 hours. After cleaning, check that the chloride ion content in the deionized water in the pipes does not exceed 100 mg / L. Nitrogen purging includes: using high-pressure nitrogen to purge the pipeline to remove residual deionized water; purging in the order of main pipe and branch pipes, with the branch pipe valves closed when purging the main pipe, and branch pipe purging starting from the first branch pipe in the direction of the cooling medium flow; after the pipeline purging is completed, inspection and confirmation are carried out according to the inspection requirements, and a record is made, and the pipeline joints are sealed.

5. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The specifications for the nitrogen used for purging are: particle size: ≤3μm, dew point: -65℃, and purity: ≥99.9%.

6. The cleaning method according to claim 1, applied to the manufacturing, installation, and flushing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The specifications of the deionized water are: pH (25℃): 5.5~8, Cl... - ≤1mg / L, Fl - : ≤1mg / L, S 2- : ≤1mg / L, conductivity (25℃): ≤3us / cm, SiO2: ≤0.1mg / L.

7. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The cleaning of the cooling system equipment includes: removing welding slag, particulate matter, etc. from inside the equipment, draining accumulated water to keep the inside dry, and sealing the external pipe interfaces after inspection and confirmation. The cooling system equipment includes a circulating water pump, a plate heat exchanger, a constant pressure water supply device, and a water distribution manifold. Sealing the pipeline after removing internal debris includes: after inspecting and confirming that there are no debris inside the pipeline, sealing it with a pipe cap or other sealing methods; The ports and sealing surfaces of the valves and pipe fittings are protected by installing flange covers or plugs.

8. The cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, is characterized in that... The prefabrication site includes a steel platform or a hardened ground surface; the prefabrication site should be kept clean and orderly. The prefabrication of the pipeline includes: stainless steel pipes used in the cooling circulation network of electronic equipment; the stainless steel pipes are cut using a saw or profile cutting machine during the cutting and welding process; before welding the joints, debris near the pipe openings should be cleaned; the stainless steel pipes are welded using manual tungsten inert gas (TIG) welding, and pipes with a diameter greater than DN200 are welded using CO2 automatic shielded welding; after the pipeline welding is completed, the slag, flux powder, and welding spatter inside and outside the pipeline are removed, the weld is repaired and cleaned, and the inner wall of the pipeline is blown with compressed air to ensure the pipeline is clean; the inert shielding gas used in the manual TIG welding includes argon and nitrogen.

9. A cleaning method according to claim 1, applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, characterized in that, Before the pipeline installation process, the surface and interior of the pipeline, valve, and fittings should be cleaned of sand, iron filings, slag, and other debris. For the prefabricated pipe sections that are handed over, the seals should be opened and the cleanliness of the interior should be checked and confirmed again. The connection methods of the connecting pipe joint include welding connection, threaded connection, and flange connection; wherein the threaded connection adopts the PTFE gasket sealing method; when the flange connection is used, a PTFE gasket is used, the diameter of the PTFE gasket is the same as the flange diameter, and the PTFE gasket is fitted with drilled holes, the number and size of which refer to the bolt holes on the flange. The flange bolts should be tightened in a diagonal sequence, and a torque wrench should be used to ensure that the preload of each bolt is consistent. During pipeline installation, open sections should be sealed during construction interruptions to prevent debris from entering the pipe. Before resuming installation, the inside of the pipe must be checked and confirmed to be clean.

10. A cleaning system applied to the manufacturing, installation, and rinsing stages of cooling circulation pipe networks for electronic devices, characterized in that, include: The pipe fitting cleaning module is used to clean cooling system equipment, remove internal debris from pipes and then seal them, and clean valves and fittings and then protect the ports and sealing surfaces of the valves and fittings. The prefabrication cleaning module is used to prefabricate pipes on the prefabrication site and clean the prefabricated pipes, including chemical degreasing, hot water rinsing, acid washing, clean water rinsing, passivation, hot water rinsing, drying and maintenance. The pipeline installation and cleaning module is used to clean the surface and interior of the pipeline, valve, and fittings before pipeline installation, and to clean the inner surface of the pipeline and valve before connecting pipe joints. The pipeline flushing module is used to sequentially clean the installed cooling circulation pipeline with cleaning fluid, fresh water, and deionized water during the pipeline flushing process, and to purge with nitrogen.

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