Detection method for evaluating high-pressure washing resistance of coating

Abstract

The invention discloses a detection method for evaluating high-pressure washing resistance of a coating, and the detection method comprises the following steps: presetting the coating on a detection sample piece, carrying out hardness detection on the coating, and washing the coating by adopting high-pressure washing equipment under a preset washing working condition under the condition that the coating meets the preset washing hardness, the preset flushing working condition comprises preset flushing pressure, the preset flushing pressure is set to be larger than or equal to 30 MPa, under the condition that the flushing operation is completed, the high-pressure flushing resistance grade of the coating is evaluated according to the denudation condition of the coating, and the coating meeting the requirement is determined according to the evaluation result; the detection method is particularly suitable for the engineering machinery product in a severe working environment, and the coating of the engineering machinery product can be detected when the engineering machinery product is off-line coated and before leaving a factory, so that the product coating meets the currently required high-pressure washing resistance requirement on the market, the appearance of the product is favorably maintained, and the durability of the product coating is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of spraying, and in particular relates to a detection method for evaluating the high-pressure washing resistance of a coating. Background Art

[0002] After the construction machinery products are used in the construction site, the surface will fall with fire retardant paint, putty dust, cement dust and other dirt, which need to be washed with a high-pressure water gun to remove the surface. At this time, the pressure generally needs to be 30-50 MPa, which requires the coating surface to have good adhesion, otherwise the coating will be damaged when the dirt is washed off. There are currently two main detection methods related to this:

[0003] 1. Pencil hardness test method: Use a pencil of appropriate hardness level (usually 7B~7H), sharpen the pencil core, apply a certain gravity and slide it on the paint film at a certain angle to see if the paint film is damaged. The corresponding level of the paint film hardness can be determined according to the damage of the paint film. Generally, the hardness of the coating is required to be between H and 2H;

[0004] 2. Grid method: Use a blade or a specific blade to draw grids on the surface of the paint film in a cross pattern (penetrating the bottom layer), and observe the damage and shedding of the paint film within the small grid range to determine the level of adhesion of the paint film. The best level for this test method to test the coating is level 0, which means that the coating basically does not fall off.

[0005] However, coatings that are evaluated as excellent by these two testing methods can only withstand flushing at a pressure of 15 MPa at most. At higher flushing pressures, the coatings are at risk of damage, especially when cleaning engineering machinery products in harsh working environments. Summary of the invention

[0006] In response to the above-mentioned defects or shortcomings, the present invention provides a detection method for evaluating the high-pressure washing resistance of a coating, aiming to solve the technical problem that the evaluation of coatings by existing detection methods cannot meet the requirements of high-pressure cleaning of engineering machinery products in harsh working environments without damage.

[0007] To achieve the above object, the present invention provides a detection method for evaluating the high-pressure washing resistance of a coating, wherein the detection method comprises:

[0008] Pre-set coating on test specimens;

[0009] Conduct hardness test on coating;

[0010] When the coating meets the preset flushing hardness, the coating is flushed with a high-pressure flushing device under a preset flushing condition, wherein the preset flushing condition includes a preset flushing pressure, and the preset flushing pressure is set to be greater than or equal to 30 MPa;

[0011] After the washing operation is completed, the coating's resistance to high-pressure washing is evaluated based on the coating's erosion.

[0012] In one embodiment of the present invention, flushing the coating at a preset flushing position using a high-pressure flushing device under a preset flushing condition includes:

[0013] A high-pressure flushing device is used to perform a first flushing operation on the surface of the coating and a second flushing operation on the edge of the damaged wound of the coating under preset flushing conditions, wherein the damaged wound of the coating is formed by pre-scratching a wound of a preset length and with the bottom exposed on the coating.

[0014] In one embodiment of the present invention, evaluating the high-pressure washing resistance level of the coating according to the erosion condition of the coating includes:

[0015] In the case where the coatings are intact after the first flushing operation and the second flushing operation, it is determined that the coatings have a higher high-pressure flushing resistance level than that under the current flushing condition;

[0016] In the case where the coating after the first flushing operation and the second flushing operation has pitting and no peeling, it is determined that the coating belongs to the high pressure flushing resistance level under the current flushing condition;

[0017] When at least one part of the coating after the first flushing operation and the second flushing operation is peeled off, it is determined that the coating has a resistance to high-pressure flushing lower than that under the current flushing condition.

[0018] In one embodiment of the present invention, after evaluating the high pressure washing resistance level of the coating according to the erosion condition of the coating, the method further includes:

[0019] When it is determined that the coating has a higher high-pressure washing resistance level than the current washing condition, the washing condition standard is increased and the washing operation is continued with the increased washing condition standard until it is determined that the coating has a high-pressure washing resistance level under the current washing condition;

[0020] When it is determined that the coating has a resistance to high-pressure flushing at a level lower than that under the current flushing condition, the flushing condition standard is lowered and the flushing operation is continued at the lowered flushing condition standard until it is determined that the coating has a resistance to high-pressure flushing at the current flushing condition.

[0021] In one embodiment of the present invention, the preset flushing pressure is set to 30 MPa to 50 MPa; and / or the preset flushing condition also includes a preset flushing time, and the preset flushing time is set to 10s to 30s.

[0022] In one embodiment of the present invention, the preset flushing condition also includes a preset flushing position, and the preset flushing position includes a preset flushing angle and a preset flushing height. The preset flushing angle is set to 70° to 90°, and the preset flushing height is set to 10cm to 30cm.

[0023] In one embodiment of the present invention, the preset flushing conditions also include the inner diameter of the spray gun of the high-pressure flushing equipment, the inner diameter of the spray gun is set to 1.0mm-1.3mm, and the spray gun of the high-pressure flushing equipment can spray columnar water mist to flush the coating.

[0024] In an embodiment of the present invention, pre-setting a coating on the test sample includes:

[0025] A powder coating or a two-component paint coating is preset on the test sample, and the test sample is baked and cooled in sequence.

[0026] In an embodiment of the present invention, performing hardness testing on the coating includes: performing hardness testing on the coating using a pencil hardness test method.

[0027] In the embodiment of the present invention, the preset flushing hardness is set to a hardness of 2H or above.

[0028] Through the above technical solution, the detection method for evaluating the high-pressure washing resistance of a coating provided by the present invention has the following beneficial effects:

[0029] When using the above-mentioned detection method, since it includes first testing the hardness of the coating, and when the coating meets the preset flushing hardness, the coating is flushed with a high-pressure flushing device at a preset flushing pressure greater than or equal to 30 MPa, and when the flushing operation is completed, the high-pressure flushing resistance level of the coating is evaluated according to the erosion of the coating, so as to determine the coating that meets the requirements based on the evaluation results. This detection method is particularly suitable for engineering machinery products in harsh working environments. The coating of engineering machinery products can be tested when the coating is off the line and before leaving the factory, thereby ensuring that the product coating meets the current high-pressure flushing resistance requirements in the market, which is conducive to maintaining the product appearance and improving the durability of the product coating. In addition, the hardness of the coating is tested before high-pressure flushing, so that low-hardness coatings can be eliminated in advance through simple testing, thereby achieving the purpose of improving detection efficiency.

[0030] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative work. In the accompanying drawings:

[0032] Figure 1 is a schematic structural diagram of a high-pressure flushing device according to an embodiment of the present invention;

[0033] Figure 2 4 is a flow chart of a method for evaluating the high-pressure washing resistance of a coating according to an embodiment of the present invention.

[0034] Explanation of the accompanying drawings: 1. High-pressure washing equipment; 2. Spray gun. DETAILED DESCRIPTION

[0035] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0036] The following describes the detection method for evaluating the high-pressure washing resistance of a coating according to the present invention with reference to the accompanying drawings.

[0037] like Figure 1 and Figure 2 As shown, the present invention provides a detection method for evaluating the high-pressure washing resistance of a coating, wherein the detection method for evaluating the high-pressure washing resistance of a coating comprises:

[0038] Step S100: pre-coating a test sample.

[0039] It can be understood that the test sample can be either a product or a test plate. Different types of coatings can be preset on the test plate, so that through subsequent testing, the high-pressure washing resistance level of different types of coatings can be determined, and the coating that meets the needs can be selected. In addition, the product can also be preset at the coating station, and subsequent testing can be carried out after the coating is off the line.

[0040] Step S200, performing hardness testing on the coating.

[0041] Specifically, before conducting the high-pressure flushing resistance test, the hardness of the coating is tested to screen out low-hardness coatings. Such coatings can be judged as low-grade without the need for high-pressure flushing resistance test. Compared with the high-pressure flushing resistance test, the hardness test of the coating is obviously more convenient and quicker, thereby improving the detection efficiency.

[0042] Step S300, when the coating meets the preset flushing hardness, the coating is flushed using the high-pressure flushing equipment 1 under the preset flushing conditions, wherein the preset flushing conditions include a preset flushing pressure, and the preset flushing pressure is set to be greater than or equal to 30 MPa.

[0043] Step S400, when the flushing operation is completed, the high-pressure flushing resistance level of the coating is evaluated according to the erosion condition of the coating.

[0044] More specifically, there are three types of damage to the coating after the flushing operation: the first is that it is intact. In this case, the flushing pressure value can be increased to perform high-pressure flushing resistance testing; the second is that the coating has slight pitting, that is, the coating is washed and eroded like cement, in which case the flushing pressure value is judged to be achievable; the third is that the coating has flaky peeling, in which case it is judged that the current flushing pressure value cannot be reached, and the flushing pressure value can be lowered for high-pressure flushing resistance testing.

[0045] When using the above-mentioned detection method, since it includes first testing the hardness of the coating, and when the coating meets the preset flushing hardness, the coating is flushed with a high-pressure flushing device 1 at a preset flushing pressure greater than or equal to 30 MPa, and when the flushing operation is completed, the high-pressure flushing resistance level of the coating is evaluated according to the erosion of the coating, so as to determine the coating that meets the requirements according to the evaluation results. This detection method is particularly suitable for engineering machinery products in harsh working environments. The coating of engineering machinery products can be tested when the coating is off the line and before leaving the factory, thereby ensuring that the product coating meets the current high-pressure flushing resistance requirements in the market, which is conducive to maintaining the product appearance and improving the durability of the product coating. In addition, the hardness of the coating is tested before high-pressure flushing, so that low-hardness coatings can be eliminated in advance through simple testing, thereby achieving the purpose of improving detection efficiency.

[0046] In one embodiment of the present invention, flushing the coating using the high pressure flushing device 1 under a preset flushing condition includes:

[0047] A high-pressure flushing device 1 is used to perform a first flushing operation on the surface of the coating and a second flushing operation on the edge of the damaged wound of the coating under preset flushing conditions, wherein the damaged wound of the coating is formed by pre-scratching a wound of a preset length and with a bottom exposed on the coating.

[0048] Understandably, in order to truly simulate the use of engineering machinery products, a destructive test item is also added, because the coating of engineering machinery products can be easily damaged by violent collisions on the construction site. Whether the damaged coating can withstand high-pressure washing is also a key indicator. The high-pressure washing resistance test should also take this into consideration. For this reason, in addition to the first flushing operation on the surface of the coating, it is also necessary to cut a wound of a preset length (for example, 10cm) on the coating, and the wound requires the coating to be damaged to the bottom, and then the second flushing operation is performed on the edge of the wound under the same preset flushing conditions. The evaluation criteria are the same as those for non-destructive testing, and generally the two results are required to be consistent to be considered qualified.

[0049] In one embodiment of the present invention, evaluating the high-pressure washing resistance level of the coating according to the erosion condition of the coating includes:

[0050] In the case where the coatings are intact after the first flushing operation and the second flushing operation, it is determined that the coatings have a higher high-pressure flushing resistance level than that under the current flushing condition;

[0051] In the case where the coating after the first flushing operation and the second flushing operation has pitting and no peeling, it is determined that the coating belongs to the high pressure flushing resistance level under the current flushing condition;

[0052] When at least one part of the coating after the first flushing operation and the second flushing operation is peeled off, it is determined that the coating has a resistance to high-pressure flushing lower than that under the current flushing condition.

[0053] Specifically, after the coating completes the first flushing operation and the second flushing operation, the erosion of the coating can be observed. If the two coating positions after the two flushing operations are intact, the actual high-pressure flushing resistance level of the coating can be determined to be higher than the high-pressure flushing resistance level under the current flushing conditions; if the two coating positions after the two flushing operations are not peeled off but at least one of them has pitting corrosion, the actual high-pressure flushing resistance level of the coating can be determined to be the high-pressure flushing resistance level under the current flushing conditions; if at least one of the two coating positions after the two flushing operations has peeled off, the actual high-pressure flushing resistance level of the coating can be determined to be lower than the high-pressure flushing resistance level under the current flushing conditions, thereby achieving a reasonable division of the high-pressure flushing resistance level of the coating.

[0054] In one embodiment of the present invention, after evaluating the high pressure washing resistance level of the coating according to the erosion condition of the coating, the method further includes:

[0055] When it is determined that the coating has a higher high-pressure washing resistance level than the current washing condition, the washing condition standard is increased and the washing operation is continued with the increased washing condition standard until it is determined that the coating has a high-pressure washing resistance level under the current washing condition;

[0056] When it is determined that the coating has a resistance to high-pressure flushing at a level lower than that under the current flushing condition, the flushing condition standard is lowered and the flushing operation is continued at the lowered flushing condition standard until it is determined that the coating has a resistance to high-pressure flushing at the current flushing condition.

[0057] More specifically, in addition to determining that the coating belongs to the high-pressure washing resistance level under the current washing condition, for the cases where the high-pressure washing resistance level is higher or lower than the current washing condition, the next high-pressure washing resistance test can be performed on the coating by continuing to adjust the washing condition standard and performing the next high-pressure washing resistance test according to the adjusted washing condition standard, so as to accurately determine the actual high-pressure washing resistance level of the coating, so as to reliably guide the flushing operation of the customer during the use of the product. In addition, since the preset washing condition includes not only the preset washing pressure, but also the preset washing time, the preset washing position and the inner diameter of the spray gun of the high-pressure washing device 1, when adjusting the washing condition standard, at least one of the preset washing pressure, the preset washing time, the preset washing position and the inner diameter of the spray gun of the high-pressure washing device 1 can be adjusted.

[0058] In one embodiment of the present invention, the preset flushing pressure is set to 30 MPa to 50 MPa. It should be particularly noted that, whether it is the first high-pressure flushing test or the subsequent flushing condition adjustment, the flushing pressure can be limited to 30 MPa to 50 MPa to avoid excessive detection. Specifically, the preset flushing pressure of the first high-pressure flushing test can be reasonably determined according to the coating process to improve the detection efficiency. At the same time, the recommended values ​​of the flushing pressure can be 30 MPa, 35 MPa, 40 MPa, 45 MPa and 50 MPa, and the flushing pressure of the high-pressure flushing equipment 1 can be adjusted.

[0059] In one embodiment of the present invention, the preset flushing condition also includes a preset flushing time, and the preset flushing time is set to 10s to 30s. It can be understood that in addition to the flushing pressure affecting the high-pressure flushing resistance of the coating, the flushing time is also one of the important influencing factors that cannot be ignored. Adding the flushing time to the consideration factors will further facilitate the accuracy of the determination of the high-pressure flushing resistance level of the coating, and facilitate reliable guidance of the flushing time for customers during the use of the product. Specifically, the recommended values ​​of the flushing time can be 10s, 20s and 30s, and the flushing time of the high-pressure flushing equipment 1 can be controlled and set.

[0060] In one embodiment of the present invention, the preset flushing condition also includes a preset flushing position, and the preset flushing position includes a preset flushing angle and a preset flushing height. The preset flushing angle is set to 70° to 90°, and the preset flushing height is set to 10cm to 30cm. It can be understood that in addition to the flushing pressure, the flushing position is also one of the important influencing factors that cannot be ignored. Adding the flushing position to the consideration factors will further facilitate the accuracy of the high-pressure flushing resistance level of the coating, and facilitate reliable guidance of the flushing position of customers during the use of the product. Specifically, there is a huge difference in the destructive force of high-pressure water flow between straight and oblique flushing, and the destructive force is the largest when the angle between the water flow and the coating is 90°. Therefore, the recommended values ​​of the flushing angle can be 70°, 80° and 90°. In addition, since the destructive force of the high-pressure water flow on the coating decays rapidly with the increase of the flushing height, the recommended values ​​of the flushing height can be 10cm, 20cm and 30cm.

[0061] In one embodiment of the present invention, the preset flushing conditions also include the inner diameter of the spray gun of the high-pressure flushing equipment 1, which is set to 1.0mm to 1.3mm, and the spray gun 2 of the high-pressure flushing equipment 1 can spray columnar water mist to flush the coating. It can be understood that the difference of 0.1mm in the inner diameter of the spray gun has a great impact on the test results. Adding the inner diameter of the spray gun to the consideration factors will further contribute to the accuracy of the determination of the high-pressure flushing resistance level of the coating, and facilitate reliable guidance for customers on the selection of the inner diameter of the spray group during the use of the product. At the same time, the water flow sprayed by the spray gun 2 of the high-pressure flushing equipment 1 is generally divided into columnar water mist and fan-shaped water mist. The destructive power of fan-shaped water mist is too different from that of columnar water mist. The selection of columnar water mist is closer to the cleaning scene of engineering machinery products. Specifically, the recommended values ​​of the inner diameter of the spray gun can be 1.0mm, 1.05mm, 1.25mm and 1.3mm.

[0062] Furthermore, when the gun is just fired, there is a pressure buildup in the water flow in the spray gun 2, and the water flow has the greatest destructive power. Before firing, the gun nozzle must be pointed to the air, and it cannot be fired at people. The coating can be tested after the water flow stabilizes after firing for 2 to 3 seconds.

[0063] Furthermore, the flushing conditions may include flushing pressure, flushing duration, flushing position and inner diameter of the spray gun. After the first high-pressure flushing resistance test, if it is determined that the high-pressure flushing resistance level is higher or lower than the current flushing condition, some or all parameters in the flushing conditions can be adjusted.

[0064] It should be noted that the high-pressure washing resistance performance requirements of the coatings that often appear in engineering machinery have the following aspects: First, a large area of ​​​​scraping is required on the coating primer, and the thickness of the scraping is generally between 0.5mm and 2㎜. The parameter index of the high-pressure washing resistance level of this coating process should reach 30 MPa / 30cm / 10S / 70°; second, the coating adopts two-component paint. After the forced baking process, the parameter index of the high-pressure washing resistance level should reach 30 MPa / 10cm / 10S / 70°; third, the coating using the powder process, the parameter index of the high-pressure washing resistance level should reach 40 MPa / 10cm / 20S / 90°. The above three tests and uses can all be based on the selection of 1.25mm inner diameter of the spray gun.

[0065] In the embodiment of the present invention, step S100, pre-setting a coating on the test sample includes:

[0066] A powder coating or a two-component paint coating is preset on the test sample, and the test sample is baked and cooled in sequence.

[0067] Specifically, the test samples of powder coating or two-component paint coating can be forced to bake according to the coating process. After baking, the hardness test can be performed after the samples have been naturally cooled for more than 24 hours. After baking, the hardness of the coating needs to be cooled and hardened for a period of time to reach the best state to ensure the reliability of the test.

[0068] In one embodiment of the present invention, step S200, testing the hardness of the coating includes: testing the hardness of the coating using a pencil hardness test method.

[0069] Furthermore, since the grid method is prone to side effects, a pencil hardness test is used to perform a preliminary hardness test on the coating, and whether a high-pressure washing resistance test is required is determined based on the hardness test results.

[0070] In one embodiment of the present invention, the preset flushing hardness is set to a hardness of 2H or more. Generally speaking, a hardness below 2H will definitely not pass the 30 MPa high pressure flushing test, so the preset flushing hardness can be set to a hardness of 2H or more.

[0071] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0072] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0073] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0074] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for evaluating the high-pressure washing resistance of a coating, characterized in that: The detection method comprises: Pre-set coating on test specimens; Conduct hardness test on coating; When the coating meets the preset flushing hardness, the coating is flushed with a high-pressure flushing device under a preset flushing condition, wherein the preset flushing condition includes a preset flushing pressure, and the preset flushing pressure is set to be greater than or equal to 30 MPa; After the washing operation is completed, the coating's resistance to high-pressure washing is evaluated based on the coating's erosion.

2. The method for evaluating the high-pressure washing resistance of a coating according to claim 1, characterized in that: The method of flushing the coating at a preset flushing position using a high-pressure flushing device under a preset flushing condition includes: A high-pressure flushing device is used to perform a first flushing operation on the surface of the coating and a second flushing operation on the edge of the damaged wound of the coating under preset flushing conditions, wherein the damaged wound of the coating is formed by pre-scratching a wound of a preset length and with the bottom exposed on the coating.

3. The method for evaluating the high-pressure washing resistance of a coating according to claim 2, characterized in that: The evaluation of the high-pressure washing resistance level of the coating according to the erosion of the coating includes: In the case where the coatings are intact after the first flushing operation and the second flushing operation, it is determined that the coatings have a higher high-pressure flushing resistance level than that under the current flushing condition; In the case where the coating after the first flushing operation and the second flushing operation has pitting and no peeling, it is determined that the coating belongs to the high pressure flushing resistance level under the current flushing condition; When at least one part of the coating after the first flushing operation and the second flushing operation is peeled off, it is determined that the coating has a resistance to high-pressure flushing lower than that under the current flushing condition.

4. The method for evaluating the high-pressure washing resistance of a coating according to claim 3, characterized in that: After evaluating the high pressure washing resistance level of the coating according to the coating erosion condition, the method further includes: When it is determined that the coating has a higher high-pressure washing resistance level than the current washing condition, the washing condition standard is increased and the washing operation is continued with the increased washing condition standard until it is determined that the coating has a high-pressure washing resistance level under the current washing condition; When it is determined that the coating has a resistance to high-pressure flushing at a level lower than that under the current flushing condition, the flushing condition standard is lowered and the flushing operation is continued at the lowered flushing condition standard until it is determined that the coating has a resistance to high-pressure flushing at the current flushing condition.

5. The method for evaluating the high-pressure washing resistance of a coating according to claim 1, characterized in that: The preset flushing pressure is set to 30 MPa to 50 MPa; and / or, the preset flushing condition also includes a preset flushing time, and the preset flushing time is set to 10s to 30s.

6. The method for evaluating the high-pressure washing resistance of a coating according to claim 1, characterized in that: The preset flushing condition also includes a preset flushing position, and the preset flushing position includes a preset flushing angle and a preset flushing height. The preset flushing angle is set to 70° to 90°, and the preset flushing height is set to 10 cm to 30 cm.

7. The method for evaluating the high-pressure washing resistance of a coating according to claim 1, characterized in that: The preset flushing conditions also include the inner diameter of the spray gun of the high-pressure flushing equipment, which is set to 1.0 mm to 1.3 mm, and the spray gun of the high-pressure flushing equipment can spray columnar water mist to flush the coating.

8. The method for evaluating the high-pressure washing resistance of a coating according to any one of claims 1 to 7, characterized in that: The pre-setting of the coating on the test sample comprises: A powder coating or a two-component paint coating is preset on the test sample, and the test sample is baked and cooled in sequence.

9. The method for evaluating the high-pressure washing resistance of a coating according to any one of claims 1 to 7, characterized in that: The hardness test of the coating comprises: using a pencil hardness test method to test the hardness of the coating.

10. The method for evaluating the high-pressure washing resistance of a coating according to any one of claims 1 to 7, characterized in that: The preset flushing hardness is set to a hardness of 2H or above.

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