Pretreatment method for industrial coating of hydraulic workpiece

Abstract

The invention relates to a pretreatment method for industrial coating of a hydraulic workpiece. The pretreatment method comprises the steps that S1, other attachments except greasy dirt on the outer surface of the hydraulic workpiece are removed; s2, oil stain treatment is conducted, specifically, the hydraulic workpiece treated in the S1 is soaked and washed with circulating alkaline water so as to remove oil stains on the hydraulic workpiece; s3, anti-flash-rust treatment is conducted, specifically, the hydraulic workpiece treated in the S2 is soaked and washed in a sectional mode through a circulating anti-flash-rust agent; and S4, the hydraulic workpiece treated in the S3 is directly used for industrial coating after being dried. The method has the beneficial effects that the adhesive force of a coating object is improved, the coating repair rate is reduced, the defects that degreasing of a traditional stand column and a jack is affected by the environment and the process is complex before the water paint coating process are overcome in the whole degreasing process, the process is simple and efficient, meanwhile, it is ensured that the green manufacturing target is achieved, and the production cost is reduced. The purposes of energy conservation, emission reduction and cost reduction are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, and in particular to a pre-treatment method for industrial coating of hydraulic workpieces. Background Art

[0002] With the continuous improvement of environmental protection awareness and the country's increased efforts to control volatile organic compounds (VOCs) emissions, traditional solvent-based paints are gradually being eliminated due to their high VOC content, and are being replaced by more environmentally friendly water-based paints. However, in practical applications, especially in the coating process of mechanical equipment such as columns, jacks and other parts, due to the physical properties of water-based paints being different from those of oil-based paints, they have certain limitations in terms of drying speed and adhesion. This has brought new challenges to industrial coatings. During the machining process, the surface of parts is often contaminated with various oil stains, such as anti-rust oil, cutting fluid, and emulsion oil generated during the assembly process. These oil stains not only affect the appearance, but more importantly, they will greatly reduce the adhesion of the coating, resulting in defects such as peeling and scaly skin after coating. In severe cases, the entire coating process may even fail, thereby increasing the cost of rework and maintenance.

[0003] At present, the industry has tried many methods to solve the oil pollution problem, including using "degreasing water" to replace traditional paint thinners for degreasing. However, the application scope of "degreasing water" is limited, especially in cold seasons, its degreasing effect is greatly reduced, and it cannot guarantee the ideal coating conditions. In addition, the secondary sandblasting method is used to remove oil pollution. Although this method is effective, it is time-consuming and labor-intensive, and increases production costs. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a pre-treatment method for industrial coating of hydraulic workpieces, which solves the technical problems of environmental limitations and high costs of the existing hydraulic workpiece degreasing methods.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] In a first aspect, an embodiment of the present invention provides a pre-treatment method for industrial coating of hydraulic workpieces, comprising the following steps:

[0009] S1. Remove all attachments other than oil stains from the outer surface of the hydraulic workpiece;

[0010] S2. Oil pollution treatment: Use circulating alkaline water to soak and rinse the hydraulic workpiece after S1 treatment to remove the oil pollution of the hydraulic workpiece;

[0011] S3, anti-flash rust treatment: use circulating anti-flash rust agent to wash the hydraulic workpiece after S2 treatment in sections;

[0012] S4. The hydraulic workpiece treated in S3 is dried and directly used for industrial coating.

[0013] As a preferred embodiment of the present invention, in the oil removal method, in S1, the process of removing attachments is to circulate clean water for immersion and flushing for 3-5 minutes, with a flushing pressure of 0.15-0.2MPa and a clean water temperature of 35-40°C.

[0014] As a preferred embodiment of the present invention, in the oil removal method, in S2, the alkaline water is a mixture of caustic soda and water, wherein the pH value of the alkaline water is 9-14;

[0015] The circulating alkaline water is used for 10-15 minutes, the flushing pressure is 0.14-0.2MPa, and the alkaline water temperature is 35-50℃.

[0016] As a preferred embodiment of the present invention, in the above-mentioned degreasing method, in S3, the flash rust preventer segmented immersion and flushing process is divided into two stages: after the first stage of immersion and flushing, the second stage of immersion and flushing is entered.

[0017] As a preferred embodiment of the present invention, in the degreasing method, in S3, the flash rust preventer is PSD-501 green rust preventive liquid with a pH of 7.5-8.5;

[0018] The two-stage immersion and flushing process is a circulating anti-flash rust agent immersion and flushing for 4-5 minutes, the flushing pressure is 0.14-0.2MPa, and the anti-flash rust agent immersion temperature is 40-45°C.

[0019] As a preferred embodiment of the present invention, in the degreasing method, in S4, the drying process is to drain the hydraulic workpiece for 3-5 minutes while blowing hot air.

[0020] As a preferred embodiment of the present invention, in the oil removal method, in S2, the liquid level and pH of the circulating alkaline water are monitored in real time, and caustic soda and / or water are supplemented.

[0021] As a preferred embodiment of the present invention, in the oil removal method, the hydraulic workpiece is a column or a jack;

[0022] The industrial coating is water-based paint coating.

[0023] (III) Beneficial effects

[0024] The beneficial effects of the present invention are as follows: the present invention provides a pretreatment method for industrial coating of hydraulic workpieces, firstly, dust, impurities and other attachments on the outer surface of the hydraulic workpiece are removed, and then the workpiece is rinsed with circulating alkaline water to remove oil stains, thereby avoiding the pollution to the environment caused by the phosphating process or organic silane; the alkaline water can effectively remove oil stains in the form of circulation, enhance the adhesion of the coating, and the alkaline water can be used repeatedly for a long time, thereby reducing costs. After the alkaline water treatment, the anti-flash rust treatment is immediately carried out, and the circulating anti-flash rust agent performs anti-rust treatment on the surface of the workpiece in sections and in sequence, thereby enhancing the thickness and density of the protective film, reducing the occurrence of flash rust, and at the same time, improving the adhesion between the subsequent coating or paint and the metal surface. After draining and blowing hot air, it can be directly used for industrial coating to improve drying efficiency. Compared with the prior art, the adhesion of the coating is improved, the coating rework rate is reduced, and the entire degreasing overcomes the defects of the traditional column and jack degreasing before the water-based paint coating process, such as being affected by the environment and the complex process. The process of the present invention is simple and efficient, while ensuring the realization of the goal of green manufacturing, energy saving, emission reduction and cost reduction.

[0025] In the process of removing attachments, the circulating clean water infiltration and flushing pressure is 0.15-0.2MPa, which is conducive to cleaning the surface of the workpiece; the clean water temperature is 35-40℃, which is convenient for cleaning and preheats the surface temperature of the workpiece, preparing for the subsequent thorough degreasing.

[0026] Alkaline water is a mixture of caustic soda and water, and the pH value of the alkaline water is 9-14, which ensures the degreasing effect. At the same time, it has a single component, low cost, simple subsequent sewage treatment process, and is environmentally friendly. Monitor the liquid level and pH of the circulating alkaline water in real time, replenish caustic soda and / or water, and add as needed to ensure the degreasing effect of the alkaline water. The circulating alkaline water is infiltrated and rinsed for 10-15 minutes, the flushing pressure is 0.14-0.2MPa, and the alkaline water temperature is 35-50℃. Under the above conditions, the circulating alkaline water can completely remove the oil on the surface of the workpiece and the micropores on the surface. The alkaline water temperature ensures the degreasing effect without damaging the seals inside the workpiece.

[0027] The flash rust preventer is PSD-501 green rust preventer with a pH of 7.5-8.5, which matches the alkaline water degreasing step. The alkaline solution remaining on the surface of the workpiece does not affect the coating effect of the flash rust preventer. At the same time, PSD-501 green rust preventer is an environmentally friendly formula that is friendly to the human body and the environment.

[0028] The flash rust preventer segmented immersion and flushing process is divided into two stages. After the first stage of immersion and flushing, it enters the second stage of immersion and flushing. Among them, the first treatment can form a preliminary protective film on the metal surface, and the second treatment can further strengthen the thickness and density of this protective film, thereby more effectively preventing oxidation reactions caused by moisture, oxygen, etc., and reducing the occurrence of flash rust. In addition, the flash rust preventer can not only prevent rust on the metal surface, but also improve the adhesion between the subsequent coating or paint and the metal surface. After two treatments, the protective layer formed is more uniform, which helps to improve the quality of the final coating and make the coating more solid and durable. Good anti-corrosion measures can reduce the frequency of repairs caused by rust and reduce maintenance costs.

[0029] The anti-flash rust agent infiltration and flushing in each stage cycle is 4-8 minutes, the flushing pressure is 0.14-0.2MPa, and the anti-flash rust agent immersion temperature is 40-45℃. Under the above-mentioned anti-flash rust agent infiltration and flushing conditions, the metal surface after infiltration and flushing is clean, the formed anti-rust layer is dense and uniform, and the residual temperature on the workpiece surface helps to improve the adhesion and overall quality of the subsequent coating and extend the service life of the coating.

[0030] After the circulating anti-flash rust agent is infiltrated and rinsed, drain the water and blow hot air for 3-5 minutes at the same time, which can not only drain the excess anti-flash rust agent, but also ensure that the remaining temperature on the surface of the workpiece is suitable for the coating of water-based paint. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a picture of the hydraulic cylinder before degreasing in Example 1 of the present invention;

[0032] Figure 2 for Figure 1 Picture of the effect after degreasing the hydraulic cylinder. DETAILED DESCRIPTION

[0033] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0034] The pretreatment method for industrial coating of hydraulic workpieces proposed in the embodiment of the present invention is aimed at the technical problems of environmental limitations and high cost of the existing hydraulic workpiece degreasing method; firstly, dust, impurities and other attachments on the outer surface of the hydraulic workpiece are removed, and then the workpiece is rinsed with circulating alkaline water to remove oil stains, avoiding the pollution to the environment caused by the phosphating process or organic silane; the alkaline water can effectively remove oil stains in the form of circulation, enhance the adhesion of the coating, and the alkaline water can be used repeatedly for a long time, reducing costs. After the alkaline water treatment, the anti-flash rust treatment is immediately carried out, and the circulating anti-flash rust agent performs anti-rust treatment on the surface of the workpiece in sections and in sequence, which can enhance the thickness and density of the protective film, reduce the occurrence of flash rust, and at the same time, improve the adhesion between the subsequent coating or paint and the metal surface. Compared with the prior art, the adhesion of the coating is improved, the coating rework rate is reduced, and the entire degreasing overcomes the defects of the traditional column and jack degreasing before the water-based paint coating process, which is affected by the environment and the process is complicated. The process of the present invention is simple and efficient, while ensuring the goal of green manufacturing, achieving the purpose of energy saving, emission reduction and cost reduction.

[0035] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0036] Example 1

[0037] This embodiment provides a pre-treatment method for industrial coating of hydraulic workpieces, which specifically includes the following steps:

[0038] (1) Circulating water immersion flushing: Figure 1 The hydraulic cylinder to be degreased is soaked and rinsed with clean water in the circulating water tank to remove dust, impurities and other attachments on its outer surface. The circulating clean water soaking and rinsing lasts for 3 minutes, the flushing pressure is 0.15MPa, and the clean water temperature is 35-40℃;

[0039] (2) The hydraulic cylinder treated in (1) is soaked and rinsed with alkaline water in a circulating water tank, wherein the mass ratio of caustic soda to water is 1:60 (pH is about 13.6), and the circulating alkaline water is soaked and rinsed for 10 minutes, the flushing pressure is 0.14 MPa, and the alkaline water temperature is 35-50°C;

[0040] (3) The hydraulic cylinder treated in (2) is passed through the circulating water tank 1 of the anti-flash rust agent, and is immersed and rinsed for 4 minutes, with a flushing pressure of 0.14 MPa and an anti-flash rust agent immersion temperature of 40°C, and the hydraulic cylinder is rinsed clean;

[0041] (4) The hydraulic cylinder treated in (3) is passed through the circulating water tank 2 of the anti-flash rust agent, immersed and rinsed for 4 minutes, the flushing pressure is 0.14 MPa, the anti-flash rust agent immersion temperature is 40°C, and the hydraulic cylinder is rinsed again.

[0042] Among them, the anti-flash rust agent used in steps (3) and (4) is PSD-501 green anti-rust liquid (manufacturer (supplier) name: Beijing Polaris Technology Industry Development Co., Ltd.), and the addition ratio of the green anti-rust liquid is 2%.

[0043] (5) Drain the hydraulic cylinder treated in (4) for 3 minutes and then move it to the subsequent water-based paint coating production line for coating. Figure 2 Shown in the figure is a hydraulic cylinder after degreasing.

[0044] Example 2

[0045] This embodiment provides a pre-treatment method for industrial coating of hydraulic workpieces. The difference between this embodiment and embodiment 1 is that:

[0046] In step (1), the clean water is circulated for 5 minutes at a flushing pressure of 0.2 MPa;

[0047] In step (2), the hydraulic cylinder treated in step (1) is soaked and rinsed with alkaline water in a circulating water tank, wherein the pH of the alkaline water is about 9, the circulating alkaline water soaking and rinsing takes 15 minutes, the flushing pressure is 0.2 MPa, and the alkaline water temperature is 35-50° C.;

[0048] The remaining steps are the same as those in Example 1.

[0049] Example 3

[0050] This embodiment provides a pre-treatment method for industrial coating of hydraulic workpieces. The difference between this embodiment and embodiment 1 is that:

[0051] When the pH of the alkaline water in step (2) is less than 9, add caustic soda to the alkaline water to adjust the pH to 9-14; if the liquid level of the alkaline water tank is not enough to immerse the workpiece, add water to the alkaline water tank;

[0052] If adding water and caustic soda is not enough to adjust the pH of the alkaline water, or if there are too many impurities in the alkaline water, remove all the alkaline water in the water tank and add alkaline water again.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pre-treatment method for industrial coating of hydraulic workpieces, characterized in that: The following steps are involved: S1. Remove all attachments other than oil stains from the outer surface of the hydraulic workpiece; S2. Oil pollution treatment: Use circulating alkaline water to soak and rinse the hydraulic workpiece after S1 treatment to remove the oil pollution of the hydraulic workpiece; S3, anti-flash rust treatment: use circulating anti-flash rust agent to wash the hydraulic workpiece after S2 treatment in sections; S4. The hydraulic workpiece treated in S3 is dried and directly used for industrial coating.

2. The oil removal method according to claim 1, characterized in that: In S1, the process of removing attachments is to circulate clean water for immersion and flushing for 3-5 minutes, with a flushing pressure of 0.15-0.2MPa and a clean water temperature of 35-40℃.

3. The pre-treatment method according to claim 1, characterized in that: In S2, the alkaline water is a mixture of caustic soda and water, wherein the pH value of the alkaline water is 9-14; The circulating alkaline water is used for 10-15 minutes, the flushing pressure is 0.14-0.2MPa, and the alkaline water temperature is 35-50℃.

4. The pre-treatment method according to claim 1, characterized in that: In S3, the flash rust preventer segmented immersion and flushing process is divided into two stages: after the first stage of immersion and flushing, it enters the second stage of immersion and flushing.

5. The pre-treatment method according to claim 4, characterized in that: In S3, the flash rust preventive agent is PSD-501 green rust preventive liquid with a pH of 7.5-8.5; The two-stage immersion and flushing process is a circulating anti-flash rust agent immersion and flushing for 4-5 minutes, the flushing pressure is 0.14-0.2MPa, and the anti-flash rust agent immersion temperature is 40-45°C.

6. The pre-treatment method according to claim 1, characterized in that: In S4, the drying process is to drain the hydraulic workpiece for 3-5 minutes while blowing hot air.

7. The pre-treatment method according to claim 3, characterized in that: In S2, the liquid level and pH of the circulating alkaline water are monitored in real time, and caustic soda and / or water are replenished.

8. The pre-treatment method according to claim 1, characterized in that: The hydraulic workpiece is a column or a jack; The industrial coating is water-based paint coating.

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