Surface treatment method for iron material inner container

Abstract

The invention relates to a surface treatment method of an iron material inner container, which comprises the following steps of: 1, putting the iron material inner container into a cleaning pool, primarily cleaning the iron material inner container by using a cleaning agent, and dissolving various types of grease in the iron material inner container; secondly, a cleaning agent is added into a soaking pool, then the iron material inner container in the first step is put into the soaking pool, the soaking time is adjusted to be 5-8 minutes, the soaking temperature is adjusted to be 30-50 DEG C, and therefore a layer of stable protective film is formed on the surface of the iron material inner container; thirdly, the iron material inner container in the second step is taken out and cleaned with clear water, and the cleaning agent remaining on the surface of the iron material inner container is removed; fifthly, the surface of the iron material inner container in the fourth step is evenly coated with enamel paint, and curing treatment is conducted; a special cleaning agent and low-frequency ultrasonic wave are adopted to assist cleaning, so that various greases and dirt on the surface of the inner container can be quickly and thoroughly dissolved and removed, and the basic cleanness of subsequent treatment is ensured.

Description

Technical Field

[0001] The invention relates to a surface treatment method for an iron material inner liner. Background Art

[0002] As an important part of pressure cookers and other kitchen appliances, the surface treatment quality of the iron liner is directly related to the adhesion of the enamel coating, corrosion resistance and the service life of the entire product. At present, the traditional surface treatment technology of the iron liner mainly relies on physical sandblasting and conventional chemical cleaning processes. These methods have the following shortcomings: Traditional physical sandblasting requires the use of special equipment, which is not only cumbersome, but also expensive and difficult to maintain. In addition, a large amount of dust and waste is generated during the sandblasting process, which not only causes serious pollution to the production environment, but also poses potential risks to the health of operators.

[0003] Conventional chemical cleaning methods are often difficult to completely dissolve and remove all kinds of stubborn oil stains on the surface of the inner tank due to the limitations of the agent formula and process control when removing grease from the surface of iron materials. At the same time, the traditional process fails to effectively form a stable protective film, resulting in the subsequent enamel coating not adhering firmly, and the corrosion resistance and high temperature resistance are insufficient, which cannot meet the requirements for long-term safe use of products such as pressure cookers.

[0004] In the existing methods, due to the use of a large amount of physical treatment and a variety of chemical agents, not only is the energy consumption high, but also the treatment of waste and exhaust gas requires additional environmental protection equipment support, which increases production costs and environmental governance pressure. Summary of the invention

[0005] The purpose of the present invention is to provide a surface treatment method for an iron liner which simplifies the process flow, reduces equipment and labor input, can quickly dissolve grease during the cleaning process, forms a stable protective film, and provides an ideal base for enamel coating.

[0006] The object of the present invention is achieved in that: A surface treatment method for an iron liner comprises the following steps: Step 1: Put the iron liner into the cleaning tank and use a cleaning agent to perform preliminary cleaning on the iron liner to dissolve various types of grease in the iron liner; Step 2: Add the cleaning agent into the soaking tank, then put the iron liner in step 1 into the soaking tank, adjust the soaking time to 5-8 minutes, and adjust the soaking temperature to 30-50℃, so that a stable protective film is formed on the surface of the iron liner; Step 3: Take out the iron liner from step 2 and clean it with clean water to remove the cleaning agent remaining on the surface of the iron liner; Step 4: Dry the iron liner from step 3 to ensure that there is no moisture left on the surface of the liner; Step 5: Evenly apply enamel paint on the surface of the iron inner tank in step 4 and perform curing treatment; Step 6: Perform performance test, adhesion test, corrosion resistance test, high temperature resistance test, wear resistance test and impact resistance test on the iron liner in step 5.

[0007] By using special cleaning agents and low-frequency ultrasonic assisted cleaning, all kinds of grease and dirt on the surface of the inner tank can be quickly and thoroughly dissolved and removed, ensuring the basic cleanliness of subsequent processing.

[0008] During the soaking process, by adjusting the time and temperature, a uniform and stable protective film is formed on the surface of the inner tank, providing an ideal base for the adhesion of the enamel coating and further preventing subsequent oxidation and corrosion.

[0009] Use clean water flushing and high-pressure water jet flushing to effectively remove residual cleaning agents and impurities, avoid interference with drying and coating processes, and ensure process continuity and product quality.

[0010] The application of temperature-controlled hot air drying or drying oven ensures that there is no moisture residue on the surface of the inner tank, while also avoiding the thermal damage to the iron material caused by high temperature, thus providing a stable environment for the subsequent curing of the enamel coating.

[0011] After curing, the uniform enamel coating has excellent corrosion resistance, high temperature resistance, wear resistance and impact resistance, which significantly improves the service life and safety of the product.

[0012] The present invention abandons the traditional physical sand blasting process, reduces equipment investment and manual operation, reduces production energy consumption and waste treatment costs, and at the same time meets green environmental protection requirements, helping to improve overall production efficiency and economic benefits.

[0013] The purpose of the present invention can also be solved by the following technical measures: Furthermore, the cleaning agent includes a surfactant that uses a compound system of multiple non-ionic surfactants and anionic surfactants, a builder that can combine with metal ions such as calcium and magnesium ions in water and soften the water quality, a corrosion inhibitor that can form an extremely thin protective film on the surface of iron materials, and deionized water.

[0014] The use of a compound system of non-ionic surfactants and anionic surfactants enables the cleaning agent to simultaneously play an emulsifying, dispersing and dissolving role, and has a significant ability to remove various types of grease and dirt, ensuring thorough cleaning of the inner tank surface.

[0015] The detergent contained in it can combine with metal ions such as calcium and magnesium in the water to effectively soften the water quality. This not only prevents hard water from interfering with the cleaning effect, but also improves the activity and stability of the detergent, making the cleaning effect more uniform and efficient.

[0016] The corrosion inhibitor forms an extremely thin protective film on the surface of the iron material, which can prevent the cleaning agent from causing corrosion damage to the iron surface during the cleaning process, provide a stable base for the subsequent enamel coating, ensure the coating adheres firmly and improve the overall corrosion resistance.

[0017] Using deionized water as solvent reduces the impact of impurities in the water on the performance of the cleaning agent, thereby ensuring the uniformity and stability of the entire cleaning process. This provides high-quality pre-treatment conditions for subsequent drying, coating and curing processes, further improving the overall performance and service life of the product.

[0018] Furthermore, the surfactant is fatty alcohol polyoxyethylene ether or sodium dodecylbenzene sulfonate; The builder is potassium hydroxide, sodium silicate or sodium gluconate; The corrosion inhibitor is a silane coupling agent.

[0019] Fatty alcohol polyoxyethylene ether and sodium dodecylbenzene sulfonate, as surfactants, can significantly reduce the surface tension of grease and dirt, promote emulsification and dispersion, and ensure that all types of grease can be quickly dissolved and removed, thereby achieving thorough cleaning.

[0020] Potassium hydroxide, sodium silicate or sodium gluconate as detergents effectively soften the water by combining with hardness ions such as calcium and magnesium in the water. This not only optimizes the activity of the detergent, but also prevents sedimentation problems caused by hard water, making the cleaning process more uniform and efficient.

[0021] As a corrosion inhibitor, silane coupling agent can quickly form an extremely thin and dense protective film on the surface of iron materials, effectively preventing chemical reagents from corroding the metal during the cleaning process. This protective film provides a stable and friendly base for the subsequent enamel coating, significantly improving the coating's adhesion and comprehensive properties such as corrosion resistance and high temperature resistance.

[0022] Furthermore, the cleaning agent includes an active agent, a builder, a corrosion inhibitor and deionized water; The active agent is fatty alcohol polyoxyethylene ether and sodium dodecylbenzene sulfonate; The builders are potassium hydroxide, sodium silicate and sodium gluconate; The corrosion inhibitor is a silane coupling agent; The fatty alcohol polyoxyethylene ether accounts for 20-25% of the total weight of the cleaning agent; the sodium dodecylbenzene sulfonate accounts for 5-10% of the total weight of the cleaning agent; the potassium hydroxide, the sodium silicate and the sodium gluconate are mixed in a ratio of 2:1:1, and their total amount accounts for 3-5% of the total weight of the cleaning agent, and are used to combine with metal ions such as calcium and magnesium in water to soften the water quality; the silane coupling agent accounts for 0.5-1% of the total weight of the cleaning agent, and forms an extremely thin protective film on the surface of the iron material; the deionized water is used to supplement the solvent to 100%.

[0023] By compounding fatty alcohol polyoxyethylene ether (20-25%) with sodium dodecylbenzene sulfonate (5-10%), the respective advantages of non-ionic and anionic surfactants can be fully utilized to achieve efficient emulsification, dispersion and dissolution of various greases and dirt, ensuring that the surface of the iron liner is thoroughly cleaned.

[0024] The detergent used (potassium hydroxide, sodium silicate, and sodium gluconate are mixed in a ratio of 2:1:1, with a total amount of 3-5%) can combine with hardness ions such as calcium and magnesium in the water, effectively soften the water, prevent hard water deposition, and thereby improve the activity and stability of the detergent, making the cleaning process more uniform and efficient.

[0025] The corrosion inhibitor (silane coupling agent, accounting for 0.5-1%) forms an extremely thin and dense protective film on the surface of the iron material, which effectively prevents the corrosion of the iron material by chemical reagents during the cleaning process. At the same time, it provides an ideal adhesion base for the subsequent enamel coating, improving the overall corrosion resistance and high temperature resistance.

[0026] Using deionized water as the solvent to make up to 100% effectively avoids interference from impurities and ensures the uniformity and repeatability of the cleaning agent formula, making the entire cleaning process more stable and ensuring consistency in product quality.

[0027] Furthermore, a low-frequency ultrasonic auxiliary device is built into the cleaning pool of step one, and the frequency range of the low-frequency ultrasonic auxiliary device is 20 to 40 kHz.

[0028] The cavitation effect produced by low-frequency ultrasound in the range of 20 to 40 kHz can form a large number of tiny bubbles in the cleaning tank. When these bubbles burst, they release high-energy microjets, which effectively impact and dissolve grease and dirt on the surface of the inner tank, thereby greatly improving the cleaning efficiency.

[0029] The cavitation effect of ultrasound can penetrate into tiny gaps and complex structures that are difficult to reach with traditional cleaning methods, ensuring that every part is cleaned evenly, avoiding residual dead corners and improving the overall cleaning quality.

[0030] Since ultrasound can accelerate the dissolution of grease and contaminants, the overall cleaning time can be shortened accordingly, and the amount of cleaning agent used may be reduced, thereby reducing production costs and chemical consumption.

[0031] When low-frequency ultrasonic cleaning is performed at an appropriate frequency, it has little impact on the base material of the iron liner and will not cause mechanical damage, providing a good base for subsequent coating treatment.

[0032] Within the frequency range of 20 to 40 kHz, it can ensure sufficient cleaning energy and achieve low-energy operation, thereby achieving the effect of energy saving and consumption reduction.

[0033] Furthermore, in step 2, 1-2% of a 10% citric acid solution is added to adjust the pH value of the surface of the iron liner to promote the uniform formation of the corrosion inhibition film, thereby improving the adhesion and corrosion resistance of the subsequent enamel coating.

[0034] Adjusting the pH value to achieve a suitable acid-base balance on the iron surface creates the best conditions for the corrosion inhibitor to form a dense and uniform protective film on the surface, ensuring the smooth progress of subsequent treatment procedures.

[0035] Citric acid can slightly corrode and activate the metal surface, which helps the corrosion inhibitor to be evenly distributed on the iron surface to form a dense and stable protective layer, thereby effectively preventing oxidation and corrosion of the iron.

[0036] The uniform and dense corrosion-inhibiting film provides an ideal adhesion base for the enamel coating, making the bond between the coating and the iron liner stronger, significantly improving the adhesion and overall durability of the coating.

[0037] By pre-adjusting the surface pH and forming a high-quality corrosion-inhibiting film, the risk of subsequent enamel coating peeling due to metal corrosion is effectively reduced, the service life of the liner is extended, and product safety is improved.

[0038] Furthermore, during the cleaning process of step three, a high-pressure water jet with a pressure of 4-6 MPa is used to flush the iron inner tank.

[0039] High-pressure water jets can quickly flush away residual cleaning agents and contaminants on the surface of the iron liner and in its tiny gaps with great impact force, ensuring that no residue interferes with subsequent processes.

[0040] The high-pressure water jet can reach hard-to-reach areas, achieving comprehensive and uniform cleaning, reducing the risk of surface re-contamination and providing an ideal clean substrate for subsequent drying and coating processes.

[0041] By adopting 4-6MPa high-pressure water jet, the cleaning efficiency can be significantly improved, the cleaning time can be shortened, and thus the operating efficiency of the overall production line can be improved.

[0042] Furthermore, in the drying process of step 4, temperature-controlled hot air drying or a drying furnace is used for drying, and the drying temperature is set at 70 to 100° C. and the drying time is 15 to 20 minutes.

[0043] By using temperature-controlled hot air or a drying oven, drying can be carried out at a temperature range of 70 to 100°C for 15 to 20 minutes to quickly evaporate the moisture on the surface of the iron liner and ensure thorough drying.

[0044] Temperature-controlled drying can ensure rapid drying while precisely controlling the temperature to avoid thermal damage or deformation of the iron material caused by excessive temperature, thereby protecting the base material quality of the liner.

[0045] The completely dry inner tank surface provides a clean and moisture-free base for the enamel coating, which helps the coating to cure evenly and improve adhesion, thereby enhancing corrosion resistance and high temperature resistance.

[0046] The use of a timed and temperature-controlled drying process can not only ensure the consistency and stability of the drying quality, but also effectively shorten the process cycle and improve overall production efficiency.

[0047] Furthermore, in the enamel coating treatment of step five, an electrostatic spraying technology is used to form a uniform and dense coating of the enamel paint on the surface of the iron inner tank, and an online coating thickness monitoring device is introduced to monitor the thickness of the enamel paint in real time.

[0048] Electrostatic spraying uses the attraction of electric charges to evenly distribute the enamel paint on the surface of the iron liner, thus forming a dense and uniform coating, which significantly improves the adhesion and durability of the coating.

[0049] The online coating thickness monitoring device can detect the coating thickness in real time to ensure that each workpiece meets the design requirements, avoid affecting subsequent performance due to too thin or too thick coating, and ensure the consistency of product quality.

[0050] Through real-time data feedback, spraying parameters (such as spraying speed, distance and flow rate) in the production process can be adjusted in a timely manner to further improve coating quality, while reducing material waste and production defects and improving overall process efficiency.

[0051] The uniform and dense enamel coating can effectively protect the iron liner, improve its corrosion resistance, high temperature resistance, wear resistance and impact resistance, thereby extending the service life of the product.

[0052] This technology combination helps to achieve automation and intelligent management of the coating process, reduce dependence on manual operations, improve production efficiency and consistency, and bring higher economic benefits to the enterprise.

[0053] Furthermore, nano-silicone particles are added to the cleaning agent in step 2 to form a corrosion protection layer embedded with nano-particles on the surface of the iron liner, and the amount of the nano-silicone particles added is 0.1-0.5% of the total weight of the cleaning agent.

[0054] Nano-silicone particles are embedded in the surface of the iron liner and form a strong physical bond with the metal substrate, forming a dense and continuous protective layer, which significantly improves the corrosion resistance of the liner.

[0055] The embedded nanoparticles can fill microscopic cracks and surface defects, reduce surface roughness, and provide a smoother base for subsequent enamel coating, thereby enhancing the adhesion and uniformity of the coating.

[0056] Due to the excellent physical and chemical stability of nanoparticles, their embedded protective layer can maintain structural integrity under conditions of high temperature and mechanical wear, extending the service life of the iron liner and reducing maintenance costs.

[0057] The beneficial effects of the present invention are as follows: The present invention can quickly and thoroughly dissolve and remove various greases and dirt on the surface of the inner tank by adopting a special cleaning agent and low-frequency ultrasonic auxiliary cleaning, thereby ensuring basic cleanliness for subsequent treatment.

[0058] The present invention, during the soaking process, adjusts the time and temperature so that a uniform and stable protective film is formed on the surface of the inner container, providing an ideal base for the attachment of the enamel coating and further preventing subsequent oxidation and corrosion.

[0059] The present invention adopts clean water flushing and high-pressure water jet flushing to effectively remove residual cleaning agent and impurities, avoid interference with drying and coating processes, and ensure process continuity and product quality.

[0060] In the present invention, the application of the temperature-controlled hot air drying or drying furnace ensures that no moisture remains on the surface of the inner container, and also avoids the thermal damage to the iron material caused by high temperature, thereby providing a stable environment for the subsequent curing of the enamel coating.

[0061] According to the present invention, after being cured, the uniform enamel coating has excellent corrosion resistance, high temperature resistance, wear resistance and impact resistance, and significantly improves the service life and safety of the product.

[0062] The present invention abandons the traditional physical sand blasting process, reduces equipment investment and manual operation, reduces production energy consumption and waste treatment costs, and at the same time meets green environmental protection requirements, helping to improve overall production efficiency and economic benefits.

[0063] The present invention adopts a compound system of nonionic surfactant and anionic surfactant, so that the cleaning agent can simultaneously play the role of emulsification, dispersion and dissolution, has a significant removal ability for various types of grease and dirt, and ensures the thorough cleaning of the inner tank surface. Moreover, the contained detergent can combine with metal ions such as calcium and magnesium in the water to effectively soften the water quality, which not only prevents hard water from interfering with the cleaning effect, but also improves the activity and stability of the cleaning agent, thereby making the cleaning effect more uniform and efficient. In addition, the corrosion inhibitor forms an extremely thin protective film on the surface of the iron material, which can prevent the cleaning agent from causing corrosion damage to the surface of the iron material during the cleaning process, and provides a stable substrate for the subsequent enamel coating, ensuring that the coating adheres firmly and improves the overall corrosion resistance. In addition, deionized water is used as a solvent, which reduces the influence of impurities in the water on the performance of the cleaning agent, thereby ensuring the uniformity and stability of the entire cleaning process. This provides high-quality pre-treatment conditions for subsequent drying, coating and curing processes, and further improves the overall performance and service life of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 Schematic diagram of the surface treatment method of the iron liner. DETAILED DESCRIPTION

[0065] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Embodiment 1, the formula of the cleaning agent is as follows: The cleaning agent includes a surfactant of a compound system of multiple nonionic surfactants and anionic surfactants, a builder that can combine with metal ions such as calcium and magnesium ions in water and soften the water, a corrosion inhibitor that can form an extremely thin protective film on the surface of iron materials, and deionized water.

[0066] The surfactant is fatty alcohol polyoxyethylene ether or sodium dodecylbenzene sulfonate; The builder is potassium hydroxide, sodium silicate or sodium gluconate; The corrosion inhibitor is a silane coupling agent.

[0067] Embodiment 2, the formula of the cleaning agent is as follows: The cleaning agent comprises an active agent, a builder, a corrosion inhibitor and deionized water; The active agent is fatty alcohol polyoxyethylene ether and sodium dodecylbenzene sulfonate; The builders are potassium hydroxide, sodium silicate and sodium gluconate; The corrosion inhibitor is a silane coupling agent; The fatty alcohol polyoxyethylene ether accounts for 20-25% of the total weight of the cleaning agent; the sodium dodecylbenzene sulfonate accounts for 5-10% of the total weight of the cleaning agent; the potassium hydroxide, the sodium silicate and the sodium gluconate are mixed in a ratio of 2:1:1, and their total amount accounts for 3-5% of the total weight of the cleaning agent, and are used to combine with metal ions such as calcium and magnesium in water to soften the water quality; the silane coupling agent accounts for 0.5-1% of the total weight of the cleaning agent, and forms an extremely thin protective film on the surface of the iron material; the deionized water is used to supplement the solvent to 100%.

[0068] A surface treatment method for an iron liner using the cleaning agent of Example 1 or Example 2 comprises the following steps: Step 1: Put the iron liner into the cleaning tank and use a cleaning agent to perform preliminary cleaning on the iron liner to dissolve various types of grease in the iron liner; Step 2: Add the cleaning agent into the soaking tank, then put the iron liner in step 1 into the soaking tank, adjust the soaking time to 5-8 minutes, and adjust the soaking temperature to 30-50℃, so that a stable protective film is formed on the surface of the iron liner; Step 3: Take out the iron liner from step 2 and clean it with clean water to remove the cleaning agent remaining on the surface of the iron liner; Step 4: Dry the iron liner from step 3 to ensure that there is no moisture left on the surface of the liner; Step 5: Evenly apply enamel paint on the surface of the iron inner tank in step 4 and perform curing treatment; Step 6: Perform performance test, adhesion test, corrosion resistance test, high temperature resistance test, wear resistance test and impact resistance test on the iron liner in step 5.

[0069] Furthermore, a low-frequency ultrasonic auxiliary device is built into the cleaning pool of step one, and the frequency range of the low-frequency ultrasonic auxiliary device is 20 to 40 kHz.

[0070] Furthermore, in step 2, 1-2% of a 10% citric acid solution is added to adjust the pH value of the surface of the iron liner to promote the uniform formation of the corrosion inhibition film, thereby improving the adhesion and corrosion resistance of the subsequent enamel coating.

[0071] Furthermore, during the cleaning process of step three, a high-pressure water jet with a pressure of 4-6 MPa is used to flush the iron liner.

[0072] Furthermore, in the drying process of step 4, temperature-controlled hot air drying or a drying furnace is used for drying, and the drying temperature is set at 70 to 100° C. and the drying time is 15 to 20 minutes.

[0073] Furthermore, in the enamel coating treatment of step five, an electrostatic spraying technology is used to form a uniform and dense coating of the enamel paint on the surface of the iron inner tank, and an online coating thickness monitoring device is introduced to monitor the thickness of the enamel paint in real time.

[0074] Furthermore, nano-silicone particles are added to the cleaning agent in step 2 to form a corrosion protection layer embedded with nano-particles on the surface of the iron liner, and the amount of the nano-silicone particles added is 0.1-0.5% of the total weight of the cleaning agent.

Claims

1. A surface treatment method for an iron liner, characterized in that: The following steps are involved: Step 1: Put the iron liner into the cleaning tank and use a cleaning agent to perform preliminary cleaning on the iron liner to dissolve various types of grease in the iron liner; Step 2: Add the cleaning agent into the soaking tank, then put the iron liner in step 1 into the soaking tank, adjust the soaking time to 5-8 minutes, and adjust the soaking temperature to 30-50℃, so that a stable protective film is formed on the surface of the iron liner; Step 3: Take out the iron liner from step 2 and clean it with clean water to remove the cleaning agent remaining on the surface of the iron liner; Step 4: Dry the iron liner from step 3 to ensure that there is no moisture left on the surface of the liner; Step 5: Evenly apply enamel paint on the surface of the iron inner tank in step 4 and perform curing treatment; Step 6: Perform performance test, adhesion test, corrosion resistance test, high temperature resistance test, wear resistance test and impact resistance test on the iron liner in step 5.

2. The surface treatment method of the iron pressure cooker inner container according to claim 1, characterized in that: The cleaning agent includes a surfactant of a compound system of multiple nonionic surfactants and anionic surfactants, a builder that can combine with metal ions such as calcium and magnesium ions in water and soften the water, a corrosion inhibitor that can form an extremely thin protective film on the surface of iron materials, and deionized water.

3. The surface treatment method of the iron pressure cooker inner container according to claim 2, characterized in that: The surfactant is fatty alcohol polyoxyethylene ether or sodium dodecylbenzene sulfonate; The builder is potassium hydroxide, sodium silicate or sodium gluconate; The corrosion inhibitor is a silane coupling agent.

4. The surface treatment method of the iron liner according to claim 1, characterized in that: The cleaning agent comprises an active agent, a builder, a corrosion inhibitor and deionized water; The active agent is fatty alcohol polyoxyethylene ether and sodium dodecylbenzene sulfonate; The builders are potassium hydroxide, sodium silicate and sodium gluconate; The corrosion inhibitor is a silane coupling agent; The fatty alcohol polyoxyethylene ether accounts for 20-25% of the total weight of the cleaning agent; the sodium dodecylbenzene sulfonate accounts for 5-10% of the total weight of the cleaning agent; the potassium hydroxide, the sodium silicate and the sodium gluconate are mixed in a ratio of 2:1:1, and their total amount accounts for 3-5% of the total weight of the cleaning agent, and are used to combine with metal ions such as calcium and magnesium in water to soften the water quality; the silane coupling agent accounts for 0.5-1% of the total weight of the cleaning agent, and forms an extremely thin protective film on the surface of the iron material; the deionized water is used to supplement the solvent to 100%.

5. The surface treatment method of the inner container of an iron pressure cooker according to any one of claims 1 to 4, characterized in that: The cleaning pool in step 1 is equipped with a low-frequency ultrasonic auxiliary device, and the frequency range of the low-frequency ultrasonic auxiliary device is 20 to 40 kHz.

6. The method for treating the surface of an iron liner according to any one of claims 1 to 4, characterized in that: Step 2 also adds 1-2% A 10% citric acid solution is used to adjust the pH value of the iron liner surface to promote the uniform formation of the corrosion inhibition film, thereby improving the adhesion and corrosion resistance of the subsequent enamel coating.

7. The method for treating the surface of an iron liner according to any one of claims 1 to 4, characterized in that: During the cleaning process of step three, a high-pressure water jet with a pressure of 4-6MPa is used to rinse the iron liner.

8. The method for treating the surface of an iron liner according to any one of claims 1 to 4, characterized in that: In the drying process of step 4, temperature-controlled hot air drying or a drying furnace is used for drying, and the drying temperature is set at 70 to 100° C. and the drying time is 15 to 20 minutes.

9. The method for treating the surface of an iron liner according to any one of claims 1 to 4, characterized in that: In the enamel coating treatment of step five, an electrostatic spraying technology is used to form a uniform and dense coating of enamel paint on the surface of the iron inner tank, and an online coating thickness monitoring device is introduced to monitor the thickness of the enamel paint in real time.

10. The method for treating the surface of an iron liner according to any one of claims 1 to 4, characterized in that: Nano-silicone particles are added to the cleaning agent in step 2 to form a corrosion-inhibiting protective layer embedded with nano-particles on the surface of the iron inner liner. The amount of the nano-silicone particles added is 0.1-0.5% of the total weight of the cleaning agent.

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