Pre-spraying method for engine cylinder cover and engine cylinder cover

Abstract

The invention provides an engine cylinder cover pre-spraying method and an engine cylinder cover The pre-spraying method comprises the steps that at least one surface of the engine cylinder cover is subjected to plasma treatment, and at least one first surface is obtained; spraying a coating on the first surface by adopting an ultrasonic spraying process so as to form a first film layer on the first surface; and carrying out ultraviolet curing treatment on the first film layer. The problem of local rusting caused by inaccurate spraying of the engine cylinder cover in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the field of local rust prevention of engine cylinder heads, and in particular to an engine cylinder head pre-spraying method and an engine cylinder head. Background Art

[0002] An efficient and environmentally friendly anti-rust treatment process is of vital importance to improving production efficiency and protecting the environment. At present, the anti-rust treatment process of the engine cylinder head is inefficient and has a long cycle time. In addition, the engine cylinder head paint is sprayed unevenly and has low adhesion. Inaccurate spraying leads to local rust, especially for engines in the ocean. Since seawater is highly corrosive, it will seriously reduce the service life of the engine cylinder head. Summary of the invention

[0003] The main purpose of the present application is to provide an engine cylinder head pre-spraying method and an engine cylinder head, so as to solve the problem of local rust caused by inaccurate spraying of the engine cylinder head in the prior art.

[0004] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for pre-spraying an engine cylinder head is provided, comprising: performing plasma treatment on at least one surface of the engine cylinder head to obtain at least one first surface; spraying a coating on the first surface using an ultrasonic spraying process to form a first film layer on the first surface; and performing ultraviolet curing treatment on the first film layer.

[0005] Optionally, in the process of performing the plasma treatment on at least one of the surfaces of the engine cylinder head, the plasma treatment time is 70-130 s, the plasma treatment temperature is 40-80° C., and the plasma treatment power is 15-25 kW.

[0006] Optionally, in the process of spraying the coating on the first surface using the ultrasonic spraying process, the power of the ultrasonic spraying process is 1.2-1.8W.

[0007] Optionally, in the process of spraying the coating on the first surface by using the ultrasonic spraying process, the coating is sprayed onto the first surface by using a nozzle, wherein a minimum distance from the nozzle to the first surface is 3 to 6 mm.

[0008] Optionally, during the UV curing treatment of the first film layer, the UV irradiation rate is 360-440 mJ / cm 2 The ultraviolet irradiation time is 70~150s.

[0009] Optionally, before performing the plasma treatment on at least one of the surfaces of the engine cylinder head, the surface is cleaned, wherein the cleaning includes cleaning the surface using an ultrasonic cleaning process.

[0010] Optionally, the cleaning treatment time is 50-150 s, the cleaning treatment temperature is 40-60° C., and the ultrasonic frequency is 20-40 kHz.

[0011] Optionally, the coating comprises one or more of high temperature heat-resistant paint, anti-rust primer, epoxy paint, polyurethane paint, ceramic-based paint, self-lubricating paint, water-based paint and UV curing paint.

[0012] According to another aspect of the present application, an engine cylinder head is provided, wherein the engine cylinder head has a second surface obtained by adopting any one of the engine cylinder head pre-spraying methods, wherein the second surface includes a first film layer.

[0013] Optionally, the thickness of the first film layer is less than 20 μm.

[0014] Applying the technical solution of the present application, the engine cylinder head is pre-sprayed, including plasma treatment of the pre-surface of the engine cylinder head, which can change the surface characteristics of the cylinder head by generating plasma on the surface of the cylinder head, improve the surface adhesion of the cylinder head, and the plasma can clean the surface of the cylinder head, activate or change the chemical and physical properties of the material surface, provide a clean base for the coating, thereby enhancing the adhesion of paint and coating; then, the surface to be sprayed is subjected to ultrasonic spraying treatment, the ultrasonic generator generates high-frequency vibration, and the vibration causes the coating to form tiny droplets, and the droplet-shaped coating can be evenly sprayed on the pre-surface of the engine cylinder head, which can achieve precise spraying on the side of the engine cylinder head, reduce the impact of the spraying process on the environment, and perform ultraviolet curing treatment on the film layer formed by spraying, reduce the curing time after spraying, which is conducive to shortening the connection of the production line with a short automation cycle (2min) and improving production capacity. In short, the above method can improve the current situation of mass production of engine cylinder heads, such as the problem that the whole machine spraying single cylinder head in the marine engine industry cannot be completely covered, resulting in rust. At the same time, the above method can also be connected with the automatic production line to improve production efficiency and reduce logistics. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 A flow chart of a method for pre-spraying an engine cylinder head provided according to an embodiment of the present application is shown;

[0017] Figure 2 A flow chart of another engine cylinder head pre-spraying method provided according to an embodiment of the present application is shown;

[0018] Figure 3 A flow chart of ultrasonic cleaning in a method for pre-spraying an engine cylinder head provided in an embodiment of the present application is shown;

[0019] Figure 4 A flow chart of plasma treatment in a method for pre-spraying an engine cylinder head provided in accordance with an embodiment of the present application is shown;

[0020] Figure 5 A flow chart of ultrasonic spraying in a method for pre-spraying an engine cylinder head provided in an embodiment of the present application is shown;

[0021] Figure 6 A schematic flow chart of each step in a method for pre-spraying an engine cylinder head provided in accordance with an embodiment of the present application is shown;

[0022] Figure 7 A schematic structural diagram of an engine cylinder head provided according to an embodiment of the present application is shown;

[0023] Figure 8 A statistical graph of the thickness of the first film layer obtained according to Examples 1 to 9 of the present application and Comparative Example 1 is shown;

[0024] Fig. 9 A statistical graph of film thickness provided according to the embodiments and comparative examples of the present application is shown;

[0025] Fig.10 A statistical graph showing the adhesion of the film layer provided according to the embodiments of the present application and the comparative examples is shown;

[0026] Fig.11 A statistical chart of salt spray resistance days provided according to the embodiments and comparative examples of the present application is shown.

[0027] The above drawings include the following reference numerals:

[0028] 1. Engine cylinder head; 11. First engine cylinder head; 12. Second engine cylinder head; 13. Third engine cylinder head; 14. Fourth engine cylinder head; 21. Cleaning tank; 211. Cleaning liquid; 212. Ultrasonic generator and oscillator; 22. Plasma treatment chamber; 23. Ultrasonic spraying station; 24. Nozzle; 241. Oil supply pump; 242. Ultrasonic generator; 243. Air supply pipeline; 25. UV curing chamber; 31. First conveyor belt; 32. Second conveyor belt; 33. Third conveyor belt; 7. Third surface. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0030] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the present invention described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element, or there may be intermediate elements. Moreover, in the specification and claims, when it is described that an element is "connected" to another element, the element may be "directly connected" to the other element, or "connected" to the other element through a third element.

[0033] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0034] Ultraviolet curing (UV curing): A technology that uses ultraviolet radiation to cure coatings. Ultraviolet light of a specific wavelength is used to trigger the photoinitiator, thereby initiating the polymerization reaction of monomers or prepolymers to quickly form a hard solid coating.

[0035] Substrate: A material that serves as the base or underlying layer during the manufacturing process and provides support for subsequent coatings, printing, decoration or other surface treatments.

[0036] As introduced in the background technology, in the prior art, the engine cylinder head paint is sprayed unevenly and has low adhesion. In order to solve the above technical problems, the embodiments of the present application provide an engine cylinder head pre-spraying method and an engine cylinder head.

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0038] Figure 1 : is a flow chart of a method for pre-spraying an engine cylinder head according to an embodiment of the present application, the method comprising the following steps:

[0039] Step S202: plasma treat at least one surface of the engine cylinder head to obtain at least one first surface.

[0040] Specifically, surface plasma treatment technology is used to generate plasma on the surface of the engine cylinder head to change the surface characteristics and improve the surface adhesion of the material. In surface plasma treatment, plasma can also be used to further clean the surface and activate or change the chemical and physical properties of the cylinder head surface, thereby enhancing the adhesion of paint or coatings.

[0041] Step S203: spraying the coating onto the first surface using an ultrasonic spraying process to form a first film layer on the first surface.

[0042] Specifically, ultrasonic spraying technology uses ultrasonic vibrations to atomize paint. During the spraying process, the ultrasonic generator generates high-frequency vibrations, which are transmitted to the paint through a special nozzle. The vibration of the nozzle causes the paint to form tiny droplets, which are then evenly sprayed onto the target surface. Ultrasonic spraying technology has significant advantages in improving spraying efficiency, saving materials and improving coating quality.

[0043] Step S204, performing ultraviolet curing treatment on the first film layer.

[0044] Specifically, surface UV curing technology refers to exposing paint or coating containing photoinitiators to high-intensity UV radiation. The photoinitiator absorbs light energy and triggers a chemical reaction, causing the monomers or prepolymers in the coating to rapidly crosslink and cure to form a hard solid coating. UV curing technology is an efficient, environmentally friendly paint curing method that can provide high-quality coatings. It is suitable for industrial applications with high requirements for production efficiency and coating quality. After the UV curing process, the surface is required to be resistant to high temperatures up to 150°C.

[0045] Through this embodiment, the engine cylinder head is pre-sprayed, including plasma treatment of the pre-sprayed surface of the engine cylinder head, which can solve the problem that the spray thickness is thick after ultrasonic spraying and the adhesion of the sprayed film layer does not reach level 0, and the plasma treatment can change the surface characteristics of the cylinder head by generating plasma on the surface of the cylinder head, improve the surface adhesion of the cylinder head, and the plasma can clean the surface of the cylinder head and activate or change the chemical and physical properties of the surface of the material, provide a clean base for the coating, thereby enhancing the adhesion of paint and coating; then, the surface to be sprayed is subjected to ultrasonic spraying treatment, the ultrasonic generator generates high-frequency vibration, and the vibration causes the coating to form tiny droplets, and the droplet-shaped coating can be evenly sprayed on the pre-sprayed surface of the engine cylinder head, and the side of the engine cylinder head can be accurately sprayed, reducing the impact of the spraying process on the environment, and can solve the problem of inaccurate spraying and greater impact on the environment in the existing technology of spraying the side of the engine cylinder head; and the film layer formed by spraying is subjected to ultraviolet curing treatment to reduce the curing time after spraying, which is conducive to shortening the production line with short automation cycle and improving production capacity. In short, the above method can improve the current situation of mass production of engine cylinder heads, such as the problem that the spray-coated single cylinder head in the marine engine industry cannot be completely covered, resulting in rust. At the same time, the above method can also be connected to the automatic production line to improve production efficiency and reduce logistics.

[0046] In addition, in the above-mentioned spraying method, ultrasonic spraying combined with plasma and ultraviolet irradiation can improve the high temperature resistance and corrosion resistance of the film layer, and can also solve the corrosion resistance of the engine cylinder head used in the ocean, that is, solve the problem of the engine cylinder head's resistance to 150° high temperature and corrosion.

[0047] In some optional embodiments, during the plasma treatment of at least one surface of the engine cylinder head, the plasma treatment time is 70-130 s, the plasma treatment temperature is 40-80° C., and the plasma treatment power is 15-25 kW.

[0048] Specifically, the plasma treatment process is used to improve the adhesion of the surface coating of the engine cylinder head, and the parameters of the plasma treatment can be adjusted according to the characteristics of the coating and the material. For example, the cylinder head is sprayed with paint. Due to the large area and complex structure of the cylinder head, in order to ensure the uniformity of the treatment and the activation effect on the surface, the treatment time needs to be increased. However, too long a time will cause unnecessary energy consumption and extend the production time. The plasma treatment time is 70~130s, which can achieve the plasma treatment effect without causing energy waste; at the same time, in order to avoid thermal damage to the substrate or coating, the plasma treatment temperature is 40~80℃; in addition, the power of the plasma treatment process is relatively small, which will reduce the stability of the plasma treatment. If the power is too large, the plasma will generate excessive heat, reducing the treatment efficiency. In addition, excessive power will also damage the surface of the engine cylinder head and affect the adhesion of the coating. The power of the plasma treatment is 15~25kW, which can ensure the generation and strength of the plasma, effectively activate the surface material of the engine cylinder head, enhance the adhesion of the layer, solve the problem that the adhesion of the spray film layer cannot reach level 0, and at the same time, reduce the treatment time to meet the needs of efficient production.

[0049] In addition, after the engine cylinder head is treated with plasma, high-energy particles (such as electrons, ions and free radicals) will be introduced to clean and activate the surface of the material. These high-energy particles can increase the roughness and surface energy of the cylinder head surface while removing surface pollutants, so that the surface can better "grasp" the coating, so that the same amount of paint can be more tightly attached to the surface, so that less paint is needed to achieve the same adhesion requirements, which indirectly controls the thickness of the coating. Plasma treatment can also change the chemical properties of the material surface, making the surface more hydrophilic or oleophilic, depending on the type of plasma gas used. In the subsequent spraying process, the surface treated with plasma makes the paint easier to spread and flow, forming a more uniform thin layer to reduce the thickness of the film after spraying.

[0050] In some optional embodiments, in the process of spraying the coating on the first surface using an ultrasonic spraying process, the power of the ultrasonic spraying process is 1.2-1.8 kW.

[0051] Specifically, during the ultrasonic spraying process, a nozzle is used to spray the coating onto the first surface, wherein the nozzle is connected to an ultrasonic generator, and during spraying, the ultrasonic generator generates high-frequency vibrations, which are transmitted to the coating in the nozzle, and the vibrations of the nozzle and the coating cause the coating to form tiny droplets, which are evenly sprayed onto the first surface to form a uniform film, and the droplet-shaped coating reduces the waste of the coating and reduces the cost. The power of the ultrasonic wave is 1.2-1.8 kW, which helps the coating to form uniform droplets, improve the spraying efficiency, save materials and improve the coating quality, and can also avoid excessive heat due to excessive power, which damages the surface of the plate, and can also avoid the problem of uneven spraying due to insufficient atomization due to too little power.

[0052] In some optional embodiments, in the process of spraying the coating on the first surface using an ultrasonic spraying process, the coating is sprayed onto the first surface using a nozzle, wherein a minimum distance from the nozzle to the first surface is 3 to 6 mm.

[0053] Specifically, during the ultrasonic spraying process, the nozzle can atomize the paint and then spray it on the engine cylinder head. The distance between the nozzle and the surface of the engine cylinder head will affect the coverage and deposition method of the paint mist. The minimum distance of 3~6mm helps to ensure the uniform distribution of the coating on the surface of the workpiece, avoiding uneven coating thickness, local accumulation or thin coating caused by being too close or too far. In addition, the above distance can improve the efficiency of coating transmission and reduce the waste of coating during the atomization process. By adjusting the distance from the nozzle to the surface, the thickness of the film layer can be accurately controlled, and the problem of uneven spraying caused by being too close or too far can be avoided, which is conducive to the formation of a film with uniform thickness.

[0054] In some optional embodiments, during the UV curing process of the first film layer, the UV irradiation rate is 360-440 mJ / cm 2 The ultraviolet irradiation time is 70~150s.

[0055] Specifically, the UV exposure rate can affect the speed and depth of the curing process. The higher the UV exposure rate, the higher the UV intensity, and the faster the curing speed. However, too high an intensity will damage the material on the surface of the cylinder head and cause the spray film to cure too quickly and the internal curing to be insufficient. The UV exposure rate is 360~440mJ / cm 2, while ensuring the curing effect, it will not damage the material on the surface of the cylinder head, nor cause the problem of insufficient curing inside the film layer. In addition, after plasma treatment, a thinner film layer is obtained, and the specific film thickness is less than 20μm, which can further increase the ultraviolet radiation rate, and at the same time will not cause the problem of uneven curing inside the film layer. The ultraviolet radiation time, that is, the curing time is inversely proportional to the ultraviolet intensity. At a lower ultraviolet radiation rate, a longer radiation time is required to complete the curing; at a higher ultraviolet radiation rate, the curing time can be shortened. The ultraviolet radiation rate is 360~440mJ / cm 2 Under such circumstances, the irradiation time is shortened to 70~150s, the film layer can be solidified, and it can be connected to the automatic production line to improve production efficiency and reduce logistics.

[0056] In some optional embodiments, before plasma treatment is performed on at least one surface of the engine cylinder head, the surface is cleaned, wherein the cleaning includes cleaning the engine cylinder head using an ultrasonic cleaning process.

[0057] Specifically, ultrasonic cleaning can effectively remove oil, dust, rust and other impurities from the surface of the cylinder head and hard-to-reach areas, and its cleaning effect is far superior to traditional cleaning methods. The tiny bubbles generated by ultrasonic vibration will produce tiny shock waves when they burst, which can penetrate into tiny pores and complex structures, thoroughly cleaning the surface, providing the best starting conditions for subsequent plasma surface treatment and spraying processes, enhancing the adhesion of the coating, and at the same time, while ensuring the cleaning effect, minimizing damage to the engine cylinder head.

[0058] In some optional embodiments, a cleaning fluid may be used to clean the engine cylinder head.

[0059] Specifically, the engine cylinder head is placed in a cleaning tank filled with cleaning fluid, and ultrasonic vibration is turned on in the cleaning tank. The cleaning fluid includes chemical components such as surfactants, alkaline or acidic compounds, chelating agents and additives, so that the cleaning fluid not only serves as a medium for ultrasonic energy transmission, but also plays a chemical and physical role. The chemical components effectively dissolve and disperse grease, dirt, metal oxides and other dirt. Alkaline compounds are particularly effective in dissolving grease, acidic compounds can help remove rust and mineral precipitation, and chelating agents can capture and stabilize hardness ions in water to prevent the formation of scale. Additives can also protect the cylinder head material from chemical erosion during the cleaning process. In addition, the cleaning fluid can keep dissolved and dispersed pollutants in a suspended state to prevent them from being re-deposited on the surface of the workpiece, thereby improving the cleaning efficiency.

[0060] In some optional embodiments, the cleaning time is 50-150 s, the cleaning temperature is 40-60° C., and the frequency of the ultrasonic wave is 20-40 kHz.

[0061] Specifically, the cleaning time is 50~150s, which can ensure that the ultrasonic energy has enough time to act on the pollutants on the surface of the cylinder head, especially for those stubborn stains that penetrate into tiny pores or grooves. Longer cleaning time helps to completely remove them and achieve a deep cleaning effect. At a temperature of 40~60℃, the dissolution efficiency of the chemical components in the cleaning fluid can be increased, while avoiding thermal damage to the cylinder head material. The cleaning frequency is 20~40kHz, which can clean the micropores and complex structures on the surface of the engine cylinder head, while removing heavy pollutants and larger particles on the surface.

[0062] In some optional embodiments, the coating includes one or more of high temperature heat-resistant paint, anti-rust primer, epoxy paint, polyurethane paint, ceramic-based paint, self-lubricating paint, water-based paint and UV curing paint.

[0063] Specifically, a coating film is formed on the surface of the engine cylinder head, and a protective film is formed on the engine cylinder head to isolate the contact between the medium in the environment and the metal, thereby protecting the engine cylinder head. High temperature heat-resistant paint can withstand high temperature environments, and the temperature range is between 150°C and 350°C. It may contain special heat-resistant additives such as silicone resin, epoxy resin or polyimide to ensure that it does not decompose or lose adhesion at high temperatures. Anti-rust primer can be sprayed before spraying high temperature heat-resistant paint to protect the metal surface from rust, wherein the anti-rust primer can be an epoxy primer containing zinc, aluminum or other anti-rust ingredients, and can specifically include epoxy zinc-rich primer, epoxy anti-rust primer, epoxy anti-corrosion primer and Mercury epoxy anti-rust paint. Epoxy paint is a two-component paint that consists of a resin and a curing agent. After curing, a very strong coating is formed, which gives the epoxy paint good chemical stability and wear resistance. Polyurethane paint has excellent weather resistance and wear resistance, as well as good adhesion and flexibility. Ceramic-based paints contain ceramic components that provide additional heat insulation and wear resistance. Self-lubricating paints can reduce friction between the engine cylinder head and other components. Self-lubricating paints may be used, among which self-lubricating paints contain lubricating components such as graphite and molybdenum disulfide. Water-based paints use water as a solvent, which reduces VOC (volatile organic compound) emissions and meets the requirements of green manufacturing. UV-curing paints cure quickly under ultraviolet light, which not only improves production efficiency, but also has good hardness and chemical resistance. Due to its fast curing characteristics, UV-curing paints reduce the use of solvents and are more environmentally friendly.

[0064] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the engine cylinder head pre-spraying method of the present application will be described in detail below in combination with specific embodiments.

[0065] This embodiment relates to a specific engine cylinder head pre-spraying method, such as Figure 2 As shown, the following steps are included:

[0066] Step S1: ultrasonically clean the workpiece to be sprayed, and dry and remove dust from the workpiece;

[0067] Step S2: Plasma treatment is performed on the workpiece to be sprayed;

[0068] Step S3: ultrasonically spraying the surface of the workpiece to be sprayed, with the paint film thickness being less than 20 μm;

[0069] Step S4: UV curing the sprayed workpiece;

[0070] Step S5: performing a spraying quality inspection on the workpiece after spraying.

[0071] Among them, UV curing does not produce harmful fumes, has lower requirements for waste disposal, and has higher environmental performance, while high-temperature curing may require consideration of the exhaust system. The cured film layer can withstand a high temperature of 150°C for a long time.

[0072] In the above embodiment, if Figure 3 As shown, step S1 may include the following steps: step S11: determining the optimal cleaning parameters corresponding to the plate according to the type of engine cylinder head, including cleaning time, temperature and frequency, etc.; step S12: clamping the workpieces in batches to the wave-generating cleaning tank for cleaning; step S13: flushing the fallen dirt with running clean water; step S14: drying the cleaned objects.

[0073] Specifically, the surface of the plate is cleaned to remove pollutants such as oil, dust, etc., and then dried.

[0074] In the above embodiment, if Figure 4 As shown, step S2 may include the following steps: step S21: transferring the pre-treated workpiece to a plasma treatment station via a conveying device; step S22: determining the optimal cleaning parameters of the plasma treatment corresponding to the workpiece according to the type of cylinder head, such as cleaning time, temperature and frequency; step S23: performing plasma treatment on the surface of the cleaned workpiece; step S24: cooling and drying the workpiece to gradually cool the surface to room temperature.

[0075] Specifically, surface plasma treatment technology is used to change the surface characteristics and improve the surface adhesion of the material by generating plasma on the surface of the material. In surface treatment, plasma can be used to further clean the surface and activate or change the chemical and physical properties of the material surface, thereby enhancing the adhesion of paints and coatings. In the cooling process of step S24, the surface is gradually cooled to room temperature to avoid abnormal internal stress caused by rapid cooling and increase the adhesion of the film layer.

[0076] In the above embodiment, if Figure 5 As shown, step S3 includes the following steps: step S31: transferring the pretreated workpiece to the ultrasonic spraying station through a transmission device; step S32: determining the power and other parameters of the ultrasonic generator according to the batch of workpieces, and adjusting the distance between the nozzle and the workpiece; step S33: the ultrasonic generator generates ultrasonic vibrations to form fine droplets of the spraying liquid, which are sprayed onto the surface of the workpiece.

[0077] Specifically, ultrasonic spraying technology uses ultrasonic vibrations to atomize paint. During the spraying process, the ultrasonic generator generates high-frequency vibrations, which are transmitted to the paint through a special nozzle. The vibration of the nozzle causes the paint to form tiny droplets, which are then evenly sprayed onto the target surface. Ultrasonic spraying technology has significant advantages in improving spraying efficiency, saving materials and improving coating quality. Spraying requires adhesion requirements of level 0.

[0078] In the above-mentioned treatment method of the engine cylinder head, the engine cylinder head is a key component inside the engine, responsible for sealing the combustion chamber, ensuring that fuel and air do not leak during the combustion process, and allowing exhaust gas to be discharged. The cylinder head is usually made of metal, which is easy to rust in a humid or corrosive environment. Spraying the engine cylinder head with a uniform coating can prevent rust from destroying the sealing of the cylinder head, resulting in reduced combustion efficiency, power loss, increased fuel consumption, and substandard exhaust emissions, thereby affecting the performance of the engine, extending the service life of the cylinder head, and reducing replacement and maintenance costs. At the same time, spraying the engine cylinder head with paint can also improve the thermal management of the cylinder head and maintain the appearance of the cylinder head. Plasma treatment of the surface of the cylinder head can change the surface characteristics of the cylinder head by generating plasma on the surface of the cylinder head, improve the surface adhesion of the cylinder head, and plasma can clean the surface of the cylinder head, activate or change the chemical and physical properties of the material surface, provide a clean base for the coating, thereby enhancing the adhesion of paint and coating; then, ultrasonic spraying treatment is performed on the surface to be sprayed, and the ultrasonic generator generates high-frequency vibration, which causes the coating to form tiny droplets. The droplet-shaped coating can be evenly sprayed on the surface of the cylinder head, which can achieve precise spraying on the side of the cylinder head, reducing the impact of the spraying process on the environment, and ultraviolet curing treatment is performed on the film layer formed by spraying, which reduces the curing time after spraying, which is conducive to shortening the connection of the production line with short automation beat and improving production capacity. In short, the above method can improve the current situation of mass production of engine cylinder heads, such as the problem that the spraying of the single cylinder head of the whole machine in the marine engine industry cannot be completely covered, resulting in rust. At the same time, the above method can also be friendly connected with the automatic production line to improve production efficiency and reduce logistics.

[0079] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of a specific engine cylinder head pre-spraying method of the present application will be described in detail below in combination with specific embodiments.

[0080] This embodiment relates to a specific engine cylinder head pre-spraying method, such as Figure 6 As shown, the following steps are included:

[0081] A first engine cylinder head 11 is provided, and the first engine cylinder head 11 is placed in a cleaning tank 21 and ultrasonically cleaned, wherein the cleaning tank 21 contains a cleaning liquid 211, and the cleaning tank 21 contains a plurality of ultrasonic generators and oscillators 212, such as Figure 6 (a) as shown;

[0082] After the first engine cylinder head 11 is cleaned, the second engine cylinder head 12 is obtained, and the second engine cylinder head 12 is transferred to the plasma treatment chamber 22 by the first conveyor belt 31, and the outer surface of the second engine cylinder head 12 is subjected to plasma treatment, such as Figure 6 (b) as shown;

[0083] After the second engine cylinder head 12 is subjected to plasma treatment, a third engine cylinder head 13 is obtained, and the third engine cylinder head 13 is transferred to the ultrasonic spraying station 23 through the second conveyor belt 32, and the outer surface of the third engine cylinder head 13 is sprayed with paint through the nozzle 24, wherein the nozzle 24 is respectively connected to the oil supply pump 241, the ultrasonic generator 242 and the air supply pipeline 243. When ultrasonic spraying is performed, the oil supply pump 241 provides paint to the nozzle 24, the ultrasonic generator 242 can make the paint form tiny droplets, and the air supply pipeline 243 provides gas to the nozzle to increase the pressure in the nozzle 24. Figure 6 (c) as shown;

[0084] After the ultrasonic spraying of the third engine cylinder head 13 is completed, a first film layer is formed on the surface of the third engine cylinder head 13 to obtain a fourth engine cylinder head 14. The fourth engine cylinder head 14 is transferred to the ultraviolet curing chamber 25 by the third conveyor belt 33, and the fourth engine cylinder head 14 is irradiated with ultraviolet rays to cure the first film layer. Figure 6 (d) shown.

[0085] In the above method, the engine cylinder head is cleaned to remove surface oil, dust and other pollutants, which provides the best starting conditions for the subsequent plasma surface treatment and spraying process and enhances the adhesion of the coating; the plasma surface treatment process can be used to further clean the cylinder head surface, remove grease, dirt, organic matter and other impurities on the material surface, provide a clean base for the coating, and increase the mechanical anchoring effect between the coating and the substrate; the ultrasonic spraying technology can be used to achieve precise spraying of the cylinder head, control the back lake of the paint, and make the spraying uniform; ultraviolet light curing technology is used only after the cylinder head is sprayed with paint, which shortens the curing and drying time of the surface paint and improves work efficiency. In addition, in the above method, overall automation can be achieved, a dark factory can be realized, no manual operation is required, the cost is reduced, and the uniform performance of the cylinder head effect is achieved.

[0086] According to another aspect of the present application, Figure 7 As shown, an engine cylinder head 1 is provided, and the engine cylinder head 1 has a third surface 7 obtained by adopting the above-mentioned processing method of the engine cylinder head, wherein the third surface 7 includes a first film layer.

[0087] Specifically, the first film layer on the above-mentioned engine cylinder head is obtained by plasma treatment and ultrasonic spraying, wherein the plasma treatment can clean the surface of the cylinder head and activate or change the chemical and physical properties of the material surface, providing a clean base for the coating, thereby enhancing the adhesion of paint and coatings; the ultrasonic spraying process is used to spray the coating on the surface of the cylinder head, and the ultrasonic generator generates high-frequency vibrations, which cause the coating to form tiny droplets. The droplet-shaped coating can be evenly sprayed onto the target surface to obtain a first film layer with uniform thickness that meets the adhesion requirements.

[0088] In some optional embodiments, the thickness of the first film layer is less than 20 μm.

[0089] Specifically, controlling the thickness of the first film layer to less than 20 μm can ensure the best contact between the first film layer and the cylinder head surface, thereby enhancing adhesion. An overly thick film layer may increase the internal stress of the first film layer, affecting its bonding with the substrate, while a moderate thickness can avoid this problem and improve the stability and durability of the first film layer. In addition, precise film layer thickness control helps to achieve uniform distribution of the first film layer on the cylinder head surface, avoiding local over-thickness or over-thinness, thereby ensuring that the entire surface has the same protective effect and appearance quality.

[0090] The above-mentioned engine cylinder head pre-spraying method in the present application will be further explained below in combination with specific embodiments and comparative examples.

[0091] Example 1

[0092] The engine cylinder head pre-spraying method provided in this embodiment comprises the following steps:

[0093] Step S301: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the ultrasonic cleaning time is 100 seconds, the cleaning temperature is 50° C., and the cleaning frequency is 30 kHz;

[0094] Step S302: Plasma treatment is performed on the cleaned surface of the engine cylinder head, wherein the plasma treatment time is 100 seconds, the plasma treatment temperature is 60° C., and the plasma treatment power is 20 kW;

[0095] Step S303: ultrasonically spraying epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 1.5 kW, and the minimum distance from the nozzle to the surface is 4 mm;

[0096] Step S304: UV curing the first film layer, wherein the UV irradiation rate is 400 mJ / cm 2 The ultraviolet irradiation time is 110s.

[0097] Example 2

[0098] The engine cylinder head pre-spraying method provided in this embodiment comprises the following steps:

[0099] Step S301: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the ultrasonic cleaning time is 50 seconds, the cleaning temperature is 40° C., and the cleaning frequency is 20 kHz;

[0100] Step S302: Plasma treatment is performed on the cleaned surface of the engine cylinder head, wherein the plasma treatment time is 70 seconds, the plasma treatment temperature is 40° C., and the plasma treatment power is 15 kW;

[0101] Step S303: ultrasonically spraying epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 1.2 kW, and the minimum distance from the nozzle to the surface is 3 mm;

[0102] Step S304: The first film layer is cured by ultraviolet curing technology, wherein the ultraviolet radiation rate is 360mJ / cm 2 The ultraviolet irradiation time is 70s.

[0103] Example 3

[0104] The engine cylinder head pre-spraying method provided in this embodiment comprises the following steps:

[0105] Step S301: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the ultrasonic cleaning time is 150 seconds, the cleaning temperature is 60° C., and the cleaning frequency is 40 kHz;

[0106] Step S302: Plasma treatment is performed on the cleaned surface of the engine cylinder head, wherein the plasma treatment time is 130 seconds, the plasma treatment temperature is 80° C., and the plasma treatment power is 25 kW;

[0107] Step S303: ultrasonically spraying epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 1.8 kW, and the minimum distance from the nozzle to the surface is 6 mm;

[0108] Step S304: The first film layer is cured by using an ultraviolet curing process, wherein the ultraviolet radiation rate is 440 mJ / cm 2 The ultraviolet irradiation time is 150s.

[0109] Example 4

[0110] The difference between this embodiment and embodiment 1 is that:

[0111] Step S301: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the ultrasonic cleaning time is 30 seconds, the cleaning temperature is 80° C., and the cleaning frequency is 10 kHz.

[0112] Example 5

[0113] The difference between this embodiment and embodiment 1 is that:

[0114] Step S302: Plasma treatment is performed on the cleaned surface of the engine cylinder head, wherein the plasma treatment time is 150 seconds, the plasma treatment temperature is 100° C., and the plasma treatment power is 30 kW.

[0115] Example 6

[0116] The difference between this embodiment and embodiment 1 is that:

[0117] Step S303: ultrasonically spray epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 2 kW and the minimum distance from the nozzle to the surface is 4 mm.

[0118] Example 7

[0119] The difference between this embodiment and embodiment 1 is that:

[0120] Step S303: ultrasonically spray epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 1.5 kW, and the minimum distance from the nozzle to the surface is 10 mm.

[0121] Example 8

[0122] The difference between this embodiment and embodiment 1 is that:

[0123] Step S304: The first film layer is cured by ultraviolet curing technology, wherein the ultraviolet radiation rate is 330mJ / cm 2 The ultraviolet irradiation time is 200s.

[0124] Example 9

[0125] The engine cylinder head pre-spraying method provided in this embodiment comprises the following steps:

[0126] Step S301: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the ultrasonic cleaning time is 30 seconds, the cleaning temperature is 80° C., and the cleaning frequency is 10 kHz;

[0127] Step S302: Plasma treatment is performed on the cleaned surface of the engine cylinder head, wherein the plasma treatment time is 150 seconds, the plasma treatment temperature is 100° C., and the plasma treatment power is 30 kW;

[0128] Step S303: ultrasonically spraying epoxy anti-rust primer on the plasma-treated surface of the engine cylinder head to form a first film layer with a thickness of 15 μm, wherein the power of the ultrasonic spraying process is 2 kW and the minimum distance from the nozzle to the surface is 10 mm;

[0129] Step S304: The first film layer is cured by ultraviolet curing technology, wherein the ultraviolet radiation rate is 330mJ / cm 2 The ultraviolet irradiation time is 200s.

[0130] Comparative Example 1

[0131] The engine cylinder head pre-spraying method provided in this comparative example comprises the following steps:

[0132] Step S401: providing an engine cylinder head, and performing ultrasonic cleaning on the surface of the engine cylinder head, wherein the cleaning time is 100 seconds, the cleaning temperature is 50° C., and the cleaning frequency is 30 kHz;

[0133] Step S402: ultrasonically spraying epoxy anti-rust primer on the cleaned surface of the engine cylinder head to form a first film layer, wherein the power of the ultrasonic spraying process is 1.5 W, and the minimum distance from the nozzle to the surface is 4 mm;

[0134] Step S403: UV curing the first film layer, wherein the UV irradiation rate is 400 mJ / cm 2 The ultraviolet irradiation time is 110s.

[0135] Five samples were prepared under the conditions of the above-mentioned embodiments 1 to 9 and comparative example 1, and the thickness of the first film layer after curing in each sample in embodiments 1 to 9 and comparative example 1 was measured by a film thickness measuring instrument; the adhesion between the first film layer after curing in each sample in embodiments 1 to 9 and comparative example 1 and the surface of the cylinder head was measured by a cross-cut method; the anti-rust performance of the first film layer after curing in each sample in embodiments 1 to 9 and comparative example 1 was tested by a salt spray test, and the obtained adhesion results are shown in Table 1, and the film layer thickness is shown in Table 1. Figure 8 The results of the number of days of salt spray resistance are shown in Table 2;

[0136] Table 1

[0137]

[0138] Table 2

[0139]

[0140] As shown in Table 1, the adhesion of the film layers after the plasma treatment, ultrasonic spraying process and UV curing treatment of the engine cylinder head can reach level 0, and the adhesion of the film layers of Examples 1 to 9 is stronger than that of Comparative Example 1; Figure 8 As shown, the thickness of the first film layer of Examples 1 to 9 is less than 20 μm, and the thickness of the film layer of Comparative Example 1 is greater than 20 μm. As shown in Table 2, the salt spray resistance days of the film layers of Examples 1 to 9 are greater than the salt spray resistance days of Comparative Example 1. It can be explained that the adhesion of the film layer after plasma treatment, ultrasonic spraying process and ultraviolet curing treatment of the engine cylinder head can reach level 0, and the film layer thickness is less than 20 μm. Plasma treatment of the engine cylinder head can solve the problem that the spraying thickness exceeds 20 μm after ultrasonic spraying and the adhesion of the spraying material does not reach level 0. In addition, through the above-mentioned spraying treatment of the engine cylinder head, the rust prevention ability of the film layer is improved.

[0141] In addition, in order to verify the stability of Example 1, 10 pieces of engine cylinder heads were prepared according to the steps of Example 1 and Comparative Example 1, and the film thickness, adhesion and salt spray resistance of the 10 pieces of engine cylinder heads obtained in Example 1 and the 10 pieces of engine cylinder heads obtained in Comparative Example 1 were measured respectively. The results are as follows: Figures 9 to 11 As shown, among which, Fig. 9 and Fig.10 As shown, the thickness of the samples in Example 1 is less than 20 μm, and the adhesion is 0; Fig. 9 and Fig.10 As shown, the thickness of the samples in Comparative Example 1 is greater than 20 μm, the adhesion is between 0 and 2, and, as Fig.11 As shown, the number of days of salt spray resistance of the sample in Example 1 is greater than or equal to the number of days of salt spray resistance of the sample in the comparative example. It can be concluded that the film thickness after plasma treatment and ultrasonic spray treatment of the engine cylinder head is less than 20μm, the adhesion is 0, and the number of days of salt spray resistance is also more than that of the comparative example, indicating that the above method can solve the problem of thick spray thickness and low adhesion of engine cylinder head coating in the prior art.

[0142] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for pre-spraying an engine cylinder head, characterized in that: include: Plasma-treating at least one surface of the engine cylinder head to obtain at least one first surface; Using an ultrasonic spraying process to spray a coating onto the first surface to form a first film layer on the first surface; The first film layer is subjected to ultraviolet curing treatment.

2. The engine cylinder head pre-spraying method according to claim 1, characterized in that: In the process of performing the plasma treatment on at least one of the surfaces of the engine cylinder head, the plasma treatment time is 70-130 seconds, the plasma treatment temperature is 40-80° C., and the plasma treatment power is 15-25 kW.

3. The engine cylinder head pre-spraying method according to claim 1, characterized in that: In the process of spraying the coating on the first surface by using the ultrasonic spraying process, the power of the ultrasonic spraying process is 1.2-1.8 kW.

4. The engine cylinder head pre-spraying method according to claim 1, characterized in that: In the process of spraying the coating on the first surface by using the ultrasonic spraying process, the coating is sprayed onto the first surface by using a nozzle, wherein a minimum distance from the nozzle to the first surface is 3-6 mm.

5. The engine cylinder head pre-spraying method according to claim 1, characterized in that: During the UV curing treatment of the first film layer, the UV irradiation rate is 360-440 mJ / cm 2 The ultraviolet irradiation time is 70~150s.

6. The engine cylinder head pre-spraying method according to claim 1, characterized in that: Before performing the plasma treatment on at least one of the surfaces of the engine cylinder head, the surface is cleaned, wherein the cleaning includes cleaning the surface using an ultrasonic cleaning process.

7. The engine cylinder head pre-spraying method according to claim 6, characterized in that: The cleaning treatment time is 50-150 seconds, the cleaning treatment temperature is 40-60° C., and the ultrasonic frequency is 20-40 kHz.

8. The engine cylinder head pre-spraying method according to claim 1, characterized in that: The coating comprises one or more of high temperature heat-resistant paint, anti-rust primer, epoxy paint, polyurethane paint, ceramic-based paint, self-lubricating paint, water-based paint and UV curing paint.

9. An engine cylinder head, characterized in that: The engine cylinder head has a second surface obtained by using the engine cylinder head pre-spraying method according to any one of claims 1 to 8, wherein the second surface includes a first film layer.

10. The engine cylinder head according to claim 9, characterized in that: The thickness of the first film layer is less than 20 μm.

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