Method for detecting terminal paint carrying risk of compressor production line during film coating

Abstract

The invention discloses a method for detecting the risk that a terminal is painted when a compressor is coated, and the method comprises the following steps: 1) arranging an electrostatic induction device in an electrophoresis tank, and arranging an electrostatic induction strip on the electrostatic induction device; (2) testing the corresponding voltage when the emulsion color paste is subjected to electrophoretic coating and the coating film reaches the set film thickness; 3) performing electrophoretic coating on the emulsion color paste, curing the coated electrostatic induction strip, and confirming the electrostatic induction level of the electrostatic induction strip; (4) adding an adjusting agent into the emulsion color paste as required, and testing the corresponding voltage when the coating film reaches the set film thickness; 5) performing electrophoretic coating on the emulsion color paste added with the regulator, curing the coated electrostatic induction strip, and confirming the electrostatic induction level of the electrostatic induction strip at the moment; and 6) judging the paint carrying risk of the compressor terminal. The method is accurate, simpler, more convenient and quicker, the production efficiency is improved, and the yield is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of cathodic electrophoretic coatings. More specifically, it relates to a method for detecting the risk of terminal paint adhesion during the coating of a compressor. Background Art

[0002] Air conditioners are regarded as one of the greatest inventions in the 20th century, and their main component, the compressor, provides the core energy for their refrigeration effect. Electrophoretic coatings began to be applied to compressor manufacturing in the 1980s and 1990s. Since the film-forming method is that the entire compressor is immersed in the coating for film formation, it provides a strong guarantee for its anti-corrosion effect, etc., thus greatly extending the service life of the compressor. During the direct current electrophoresis process, due to the electrostatic induction of the coating at the wiring terminal part of the compressor, the coating will adhere to the wiring terminal.

[0003] After the abnormal adhesion on the wiring terminal is dried, it will cause abnormalities such as electric arcing during the assembly line test. Excessive adhered coating film will also cause problems such as intermittent malfunction of the motor. In the past, major manufacturers all used rubber plugs to block them. The addition of this process greatly reduced the production line speed. At the same time, because the plug is easily pulled out together with the paint at the bottom of the plug during the unplugging process, the product yield is greatly reduced.

[0004] As for the current use process of electrophoretic coatings, there has been no unified technical standard to measure and guide the laboratory development and the situation after customer application for the case of terminal paint adhesion. There are still many electrophoretic coatings on the market claiming to achieve the effect of no terminal paint adhesion, etc., confusing the perspective of application manufacturers. And the traditional detection method of viewing the film thickness of electrophoresis simply cannot measure the effect of electrophoretic coatings on terminal paint adhesion.

[0005] Therefore, there is an urgent need for a detection method and device for terminal paint adhesion to truly reflect the initial terminal paint adhesion effect of electrophoretic coatings through comparative tests, and the terminal paint adhesion effect situation after simulating on-site adjustment of relevant parameters. Thus, it is possible to avoid the problem of abnormal input of a large amount of manpower and material resources to solve the problem without knowing it. Summary of the Invention

[0006] Based on the above facts, the purpose of the present invention is to provide a method for detecting the risk of terminal paint adhesion during the coating of a compressor.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A method for detecting the risk of terminal paint adhesion during the coating of a compressor, comprising the following steps:

[0009] 1) Set an electrostatic induction device in the electrophoresis tank, wherein the electrostatic induction device is provided with an electrostatic induction strip;

[0010] 2) During the set electrophoresis time t1, test the voltage corresponding to when the coating film reaches the set film thickness after the emulsion color paste is electrophoretically coated, and record it as V1;

[0011] 3) Place the emulsion color paste in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V1, perform electrophoretic coating, wash, dry the electrophoretically coated static induction strip, and bake it at the curing temperature of the emulsion color paste to confirm the static induction level of the static induction strip;

[0012] 4) According to actual needs, add a regulator to the emulsion color paste. During the set electrophoresis time t1, test the voltage corresponding to when the coating film reaches the aforementioned set film thickness after the emulsion color paste is electrophoretically coated, and record it as V2;

[0013] 5) Place the emulsion color paste added with the regulator in step 4) in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V2, perform electrophoretic coating, wash, dry the electrophoretically coated static induction strip, and bake it at the curing temperature of the emulsion color paste added with the regulator to confirm the static induction level of the static induction strip at this time;

[0014] 6) Judge the paint - carrying risk of the compressor terminal according to the static induction levels obtained in step 3) and step 5).

[0015] Further, the emulsion color paste is aged and filtered before use.

[0016] Further, the mass lost after aging in the emulsion color paste is made up with water.

[0017] Further, before step 4), it also includes repeating the steps of step 2) and step 3) multiple times, and finally determining the static induction level of the static induction strip based on the average value of the static induction levels of the static induction strip each time.

[0018] Further, before step 6), it also includes repeating the steps of step 4) and step 5) multiple times, and finally determining the static induction level of the static induction strip based on the average value of the static induction levels of the static induction strip each time.

[0019] Further, in step 1), in the electrophoresis tank, the static induction device is located in the middle area of the electrophoresis tank.

[0020] Further, the material of the static induction device is fiber - reinforced plastic (FRP) or the static induction device is a device without ion precipitation.

[0021] Further, the material of the static induction strip is tin - plated steel sheet.

[0022] Further, in step 1), in the electrophoresis tank, the positive pole of the power supply is connected to the anode plate, and the negative pole of the power supply is connected to two phosphating plates.

[0023] Furthermore, the solid content of the emulsion color paste is 15-20%, and the ash content is 13-16%.

[0024] Furthermore, in step 6), the method for judging the risk of paint on the compressor terminal includes the following steps:

[0025] Take the average value of the sum of the electrostatic induction levels obtained in step 3) and step 5), denoted as S1;

[0026] If S1 > 2, it is determined that the risk is relatively large;

[0027] If S1 ≤ 2, it is determined that the risk is controllable.

[0028] Furthermore, the method for setting the electrostatic induction level is as follows:

[0029] Set the length of the electrostatic induction strip immersed in the emulsion color paste as h;

[0030] If there is no paint adhesion on the electrostatic induction strip, the level is 0;

[0031] If there is paint adhesion on the electrostatic induction strip with a length less than (3 / 13)h, the level is 1;

[0032] If there is paint adhesion on the electrostatic induction strip with a length less than (6 / 13)h and greater than (3 / 13)h in the length perpendicular to the electrophoresis direction, the level is 2;

[0033] If there is paint adhesion on the electrostatic induction strip with a length less than (11 / 13)h and greater than (6 / 13)h in the length perpendicular to the electrophoresis direction, the level is 3;

[0034] If there is paint adhesion on the electrostatic induction strip with a length less than h and greater than (11 / 13)h in the length perpendicular to the electrophoresis direction, the level is 4.

[0035] The beneficial effects of the present invention are as follows:

[0036] Compared with the current technical means, the detection method provided by the present invention is accurate and can more simply and quickly measure the paint situation on the terminals of the emulsion color paste; at the same time, after sufficient ripening, the comprehensive evaluation of the influence of each solvent factor on the paint on the terminals of the electrophoresis coating is preferably carried out, and the obtained results are graded. By tracking and comparing the new production line, the best level standard is found, which has guiding significance in the product development and product application process, effectively avoids the situation of paint on the terminals without knowing it and having to use rubber plugs, and improves production efficiency and product qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The following further describes in detail the specific embodiments of the present invention with reference to the drawings.

[0038] Figure 1 The structural schematic diagram of the electrophoresis tank in some examples is shown.

[0039] Figure 2 The schematic diagram of the setting method of the static induction level in some examples is shown. Detailed implementation manners

[0040] To illustrate the present invention more clearly, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. Similar components in the drawings are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0041] According to a specific implementation manner of the present invention, a method for detecting the risk of terminal paint on the compressor during film coating is provided. The method includes the following steps:

[0042] 1) A static induction device is arranged in the electrophoresis tank, and a static induction strip is provided in the static induction device.

[0043] Exemplarily, the structural schematic diagram of the electrophoresis tank is as Figure 1 shown. It can be seen that in step 1), in the electrophoresis tank, the static induction device is located in the middle area of the electrophoresis tank.

[0044] Exemplarily, the size of the static induction device is 20 cm × 10 cm × 20 cm, and the material is preferably fiber reinforced plastic (FRP) or the static induction device is a device without ion precipitation.

[0045] Exemplarily, the static induction strip is made of tin-plated steel sheet (tinned iron), preferably cut into a size of 0.5 cm × 15 cm, and the induction strip is suspended with an insulating material. Ensure that the immersed area of the static induction strip is 10 - 13 cm, preferably 10 cm; the anode is made of 304 stainless steel, preferably with a size of 7 cm × 20 cm, and the placement area is close to the anode area; the cathode is preferably made of cold-rolled steel sheet treated with zinc phosphate system, and the size is preferably 7 cm × 15 cm.

[0046] Exemplarily, in step 1), in the electrophoresis tank, the positive pole of the power supply is connected to the anode plate, and the negative pole of the power supply is connected to two phosphating plates. The connection of the phosphating plates can better ensure sufficient induced current during the electrophoresis process.

[0047] 2) During the set electrophoresis time t1, test the voltage corresponding to the set film thickness after the emulsion color paste is electrophoretically coated, and record it as V1.

[0048] In some examples, in step 2), the emulsion color paste is aged and filtered before use. Through the aging treatment, the emulsion color paste can be completely melted. The mass lost after aging in the emulsion color paste can be further supplemented with water.

[0049] The aging conditions include but are not limited to aging at 40 °C for 16 h.

[0050] Before the emulsion color paste is placed in the electrophoresis tank in the subsequent step 3), to prevent particle interference, it needs to be filtered. A filter cloth with a pore size of 5 - 100 μm is selected for testing; preferably, a 25-μm filter bag is used for filtration, and after confirming that there are no impurities or other abnormal conditions, the next step can be carried out.

[0051] Exemplarily, the solid content of the emulsion color paste is 15 - 20%, and the ash content is 13 - 16%. Preferably, the emulsion color paste has a solid content of 18% and an ash content of 13%.

[0052] 3) Place the emulsion color paste in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V1, carry out electrophoresis coating, wash, dry the electrostatic induction strip after coating, and bake it at the curing temperature of the emulsion color paste, and confirm the electrostatic induction level of the electrostatic induction strip.

[0053] In some examples, before step 4), the steps of repeating step 2) and 3) multiple times may also be included, and the average value of the electrostatic induction levels of the electrostatic induction strip each time is used to finally determine the electrostatic induction level of the electrostatic induction strip in step 3). By measuring the electrostatic induction level of the electrostatic induction strip multiple times, the measurement result is more accurate. For example, the number of repetitions can be 2 - 5 times, such as 2 times, 3 times, 4 times, etc.

[0054] Exemplarily, the conditions for washing are to wash in pure water for 10 s; the drying method is to stand in the air for 30 s.

[0055] 4) According to actual needs, an adjuster is added to the emulsion color paste. Within the set electrophoresis time t1, the voltage corresponding to the film thickness reaching the aforementioned set value after electrophoresis coating of the emulsion color paste is measured and recorded as V2;

[0056] Exemplarily, the solid content of the emulsion color paste with the adjuster added is 15 - 20%, and the ash content is 13 - 16%. Preferably, the emulsion color paste with the adjuster added has a solid content of 18% and an ash content of 13%.

[0057] 5) Place the emulsion color paste with the adjuster added in step 4) in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V2, carry out electrophoresis coating, wash, dry the electrostatic induction strip after coating, and bake it at the curing temperature of the emulsion color paste with the adjuster added, and confirm the electrostatic induction level of the electrostatic induction strip at this time;

[0058] The number of times of adding the regulator can be one, two or multiple times. The regulator can be a solvent and / or an acid, which is specifically determined according to the actual application requirements. For example, the solvent can be added for adjustment; or the solvent and the acid can be added simultaneously for adjustment.

[0059] Exemplary regulators include, but are not limited to, those selected from ether alcohol co-solvents such as ethylene glycol hexyl ether, propylene glycol phenyl ether, ethylene glycol isooctyl ether, and ethylene glycol butyl ether. Due to their excellent water solubility, ethylene glycol butyl ether is preferably used for adjustment; also, acid additives such as formic acid, acetic acid, and aminosulfonic acid, etc. Considering safety and the wide range of use, acetic acid is preferably used for adjustment.

[0060] Exemplarily, the conditions for the water washing are to wash in pure water for 10 s; the drying method is to stand in the air for 30 s.

[0061] In some examples, before performing the following step 6), the steps of repeating step 4) and 5) multiple times may further be included, and the average value of the electrostatic induction levels of the electrostatic induction strips each time is used to finally determine the electrostatic induction level of the electrostatic induction strip in step 5). By measuring the electrostatic induction levels of the electrostatic induction strips multiple times, the measurement results are made more accurate. For example, the number of repetitions can be 2 - 5 times, such as 2 times, 3 times, 4 times, etc.

[0062] 6) Judge the risk of paint on the compressor terminal according to the electrostatic induction levels obtained in step 3) and step 5).

[0063] In some specific examples, in step 6), the method for judging the risk of paint on the compressor terminal includes the following steps:

[0064] Take the average value of the sum of the electrostatic induction levels obtained in step 3) and step 5), denoted as S1;

[0065] If S1 > 2, it is determined that the risk is relatively large;

[0066] If S1 ≤ 2, it is determined that the risk is controllable.

[0067] Among them, the method for setting the electrostatic induction level can be:

[0068] Set the length of the electrostatic induction strip immersed in the emulsion color paste to be h;

[0069] If there is no coating attached to the electrostatic induction strip, the level is 0;

[0070] If there is coating attached to the electrostatic induction strip on a length of less than (3 / 13)h, the level is 1;

[0071] If there is coating attached to the electrostatic induction strip on a length that is less than (6 / 13)h and greater than (3 / 13)h in the length perpendicular to the electrophoresis direction, the level is 2;

[0072] If there is paint adhesion on the length of the static induction bar perpendicular to the electrophoresis direction and the length is less than or equal to (11 / 13)h and greater than (6 / 13)h, the grade is 3.

[0073] If there is paint adhesion on the length of the static induction bar perpendicular to the electrophoresis direction and the length is less than or equal to h and greater than (11 / 13)h, the grade is 4.

[0074] Through the above solution, the method can accurately, simply and quickly test the paint situation of the terminal of the emulsion color paste.

[0075] In some specific examples, such as Figure 2 As shown. Set the length of the static induction bar to 13 cm immersed in the emulsion color paste. Then, if there is paint adhesion on the length of the static induction bar less than or equal to 3 cm, the grade is 1;

[0076] If there is paint adhesion on the length of the static induction bar perpendicular to the electrophoresis direction and the length is less than or equal to 6 cm and greater than 3 cm, the grade is 2;

[0077] If there is paint adhesion on the length of the static induction bar perpendicular to the electrophoresis direction and the length is less than or equal to 11 cm and greater than 6 cm, the grade is 3;

[0078] If there is paint adhesion on the length of the static induction bar perpendicular to the electrophoresis direction and the length is less than or equal to 13 cm and greater than 11 cm, the grade is 4.

[0079] In some examples, in the above detection method, the test temperature is 26 - 30 °C, and the preferred temperature is 28 °C.

[0080] The technical solution of the present invention will be described below in conjunction with some specific embodiments:

[0081] Example 1

[0082] Prepare three portions of the electrophoresis bath solution 1, and its formula (parts by weight) is as follows:

[0083]

[0084] After the prepared electrophoresis bath solution is aged at 40 °C for 16 hours, deionized water (pure water) is used to make up the weight to prepare an electrophoretic coating sample. The bath solution is filtered with a filter cloth with a fineness of 25 microns and reserved for use.

[0085] Analyze and confirm the bath solution parameters, and confirm that its solid content is 19.12% and the ash content is: 15.35%;

[0086] Pour the bath solution into the terminal paint simulation device respectively for film thickness voltage test and confirmation. The electrophoresis time is set as: 30-second soft start + 150-second electrophoresis time. When the film thickness is 20 microns, the voltage is 180V.

[0087] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the electrostatic induction area to the induction strip. Set the voltage as: 180V; set the electrophoresis time as: 30-second soft start + 150-second electrophoresis time, and start to prepare the electrostatic induction strip.

[0088] After electrophoresis, quickly place the electrostatic induction strip under pure water for cleaning for 10s, and let it stand in the air for 30s. Then bake it at 120°C for 20 minutes and dry it for standby for terminal paint detection (that is, for the detection and determination of the electrostatic induction level after normal temperature curing).

[0089] Adjust the additives for the second portion of the bath solution after curing and filtration. Use 2.5g of ethylene glycol monobutyl ether as the added solvent. Set the electrophoresis time as: 30-second soft start + 150-second electrophoresis time. When the temperature is 28°C and the film thickness is 20 microns, the voltage is 150V.

[0090] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the electrostatic induction area to the induction strip. Set the voltage as: 150V; set the electrophoresis time as: 30-second soft start + 150-second electrophoresis time, and start to prepare the electrostatic induction strip.

[0091] After electrophoresis, quickly place the electrostatic induction strip under pure water for cleaning for 10s, and let it stand in the air for 30s. Then bake it at 120°C for 20 minutes and dry it for standby for terminal paint detection (that is, for the detection and determination of the electrostatic induction level after solvent adjustment).

[0092] Adjust the additives again for the third portion of the bath solution after curing and filtration. Add acetic acid for conductivity adjustment. When 0.725g is added and the conductivity is adjusted to 1800μm / cm 2 At this time, add ethylene glycol monobutyl ether for adjustment. Add 1.5g. Set the electrophoresis time as: 30-second soft start + 150-second electrophoresis time. When the film thickness is 20 microns, the voltage is 150V.

[0093] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the electrostatic induction area to the induction strip. Set the voltage as: 150V; set the electrophoresis time as: 30-second soft start + 150-second electrophoresis time, and start to prepare the electrostatic induction strip.

[0094] After the electrophoresis is completed, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes until it is dried for standby for terminal paint detection (that is, for the detection and determination of the static induction level after solvent + acid adjustment).

[0095] Example 2

[0096] Prepare three portions of the electrophoresis bath solution 2, and its formula (parts by weight) is as follows:

[0097]

[0098] After the prepared electrophoresis bath solution is aged at 40 °C for 16 hours, make up the weight with deionized water (pure water) to prepare an electrophoresis coating film sample. Filter the bath solution with a filter cloth with a fineness of 25 microns and set it aside for use.

[0099] Analyze and confirm the bath solution parameters, and confirm that its solid content is 25.42% and the ash content is 20.15%;

[0100] Pour the bath solution into the terminal paint simulation device respectively for film thickness voltage test and confirmation. Set the electrophoresis time to: 30 s soft start + 150 s electrophoresis time. When the film thickness is 20 microns, the voltage is 160 V.

[0101] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. Set the voltage to: 160 V; set the electrophoresis time to: 30 s soft start + 150 s electrophoresis time, and start to prepare the static induction strip.

[0102] After the electrophoresis is completed, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes until it is dried for standby for terminal paint detection (that is, for the detection and determination of the static induction level after aging at room temperature).

[0103] Adjust the additive of the second portion of the aged and filtered bath solution. Add 0.8 g of ethylene glycol monobutyl ether as the solvent. Set the electrophoresis time to: 30 s soft start + 150 s electrophoresis time. When the temperature is 28 °C and the film thickness is 20 microns, the voltage is 150 V.

[0104] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. Set the voltage to: 150 V; set the electrophoresis time to: 30 s soft start + 150 s electrophoresis time, and start to prepare the static induction strip.

[0105] After electrophoresis, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes, and dry it for standby for terminal paint detection (that is, for the detection and determination of the static induction level after solvent adjustment).

[0106] The third portion of the aged and filtered bath solution was adjusted again with additives. Acetic acid was added for conductivity adjustment. When 0.04 g was added, the conductivity was adjusted to 1800 μm / cm 2 At this time, ethylene glycol monobutyl ether was added for adjustment. 0.27 g was added, and the electrophoresis time was set to: 30 s soft start + 150 s electrophoresis time. When the film thickness was 20 μm, the voltage was 150 V.

[0107] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. According to the voltage setting of: 150 V; the electrophoresis time setting of: 30 s soft start + 150 s electrophoresis time, start to prepare the static induction strip.

[0108] After electrophoresis, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes, and dry it for standby for terminal paint detection (that is, for the detection and determination of the static induction level after solvent + acid adjustment).

[0109] Example 3

[0110] Prepare three portions of electrophoresis bath solution, and its formula (parts by weight) is as follows:

[0111]

[0112] After the prepared electrophoresis bath solution is aged at 40 °C for 16 hours, make up the weight with deionized water (pure water) to prepare an electrophoresis coating film sample. Filter the bath solution with a 25-micron fineness filter cloth and set it aside.

[0113] Analyze and confirm the bath solution parameters, and confirm that its solid content is 12.31% and the ash content is: 8.75%;

[0114] Pour the bath solution into the terminal paint simulation device respectively for film thickness and voltage test and confirmation. The electrophoresis time is set to: 30 s soft start + 150 s electrophoresis time. When the film thickness is 20 μm, the voltage is 200 V.

[0115] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. According to the voltage setting of: 200 V; the electrophoresis time setting of: 30 s soft start + 150 s electrophoresis time, start to prepare the static induction strip.

[0116] After electrophoresis, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes and dry it for standby for terminal paint detection (that is, for the detection and determination of the static induction level after aging at room temperature).

[0117] Adjust the additives of the second portion of the aged and filtered bath solution. The solvent added is 3.56 g of ethylene glycol monobutyl ether, and the electrophoresis time is set as: 30 s soft start + 150 s electrophoresis time. When the temperature is 28 °C and the film thickness is 20 μm, the voltage is 150 V.

[0118] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. Start preparing the static induction strip according to the voltage set as: 150 V; the electrophoresis time set as: 30 s soft start + 150 s electrophoresis time.

[0119] After electrophoresis, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes and dry it for standby for terminal paint detection (that is, for the detection and determination of the static induction level after solvent adjustment).

[0120] Adjust the additives of the third portion of the aged and filtered bath solution again. Add acetic acid for conductivity adjustment. When 1.15 g is added and the conductivity is adjusted to 1800 μm / cm 2 at this time, add ethylene glycol monobutyl ether for adjustment. Add 2.15 g, and the electrophoresis time is set as: 30 s soft start + 150 s electrophoresis time. When the film thickness is 20 μm, the voltage is 150 V.

[0121] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphating plates, and the static induction area to the induction strip. Start preparing the static induction strip according to the voltage set as: 150 V; the electrophoresis time set as: 30 s soft start + 150 s electrophoresis time.

[0122] After electrophoresis, quickly place the static induction strip under pure water for cleaning for 10 s, and let it stand in the air for 30 s. Then bake it at 120 °C for 20 minutes and dry it for standby for terminal paint detection (that is, for the detection and determination of the static induction level after solvent + acid adjustment).

[0123] Example 4

[0124] Prepare three portions of electrophoresis bath solution 4, and its formula (parts by weight) is as follows:

[0125]

[0126] The prepared electrophoretic bath solution was aged at 40 °C for 16 hours, and the weight was replenished with deionized water (pure water) to prepare an electrophoretic coating film sample. The bath solution was filtered using a filter cloth with a fineness of 25 microns and set aside.

[0127] The bath solution parameters were analyzed and confirmed. It was confirmed that the solid content was 19.15% and the ash content was 15.25%.

[0128] The bath solution was poured into the terminal strip painting simulation device respectively for film thickness voltage test and confirmation. The electrophoresis time was set as: 30 seconds soft start + 150 seconds electrophoresis time. When the film thickness was 20 microns, the voltage was 230V.

[0129] The positive pole of the power supply was connected to the anode plate, the negative pole of the power supply was connected to two phosphating plates, and the electrostatic induction area was connected to the induction strip. According to the voltage set as: 230V; the electrophoresis time was set as: 30 seconds soft start + 150 seconds electrophoresis time, and the preparation of the electrostatic induction strip was started.

[0130] After electrophoresis, the electrostatic induction strip was quickly placed under pure water for cleaning for 10s and left stationary in the air for 30s. Then it was baked at 120 °C for 20 minutes and dried for standby for terminal strip painting detection (that is, for the detection and determination of the electrostatic induction level after normal temperature aging).

[0131] The second portion of the aged and filtered bath solution was adjusted with additives. The solvent added was 4.13 g of ethylene glycol monobutyl ether. The electrophoresis time was set as: 30 seconds soft start + 150 seconds electrophoresis time. When the temperature was 28 °C and the film thickness was 20 microns, the voltage was 150V.

[0132] The positive pole of the power supply was connected to the anode plate, the negative pole of the power supply was connected to two phosphating plates, and the electrostatic induction area was connected to the induction strip. According to the voltage set as: 150V; the electrophoresis time was set as: 30 seconds soft start + 150 seconds electrophoresis time, and the preparation of the electrostatic induction strip was started.

[0133] After electrophoresis, the electrostatic induction strip was quickly placed under pure water for cleaning for 10s and left stationary in the air for 30s. Then it was baked at 120 °C for 20 minutes and dried for standby for terminal strip painting detection (that is, for the detection and determination of the electrostatic induction level after solvent adjustment).

[0134] The third portion of the aged and filtered bath solution was adjusted with additives again. Acetic acid was added for conductivity adjustment. When 0.172 g was added and the conductivity was adjusted to 1800 μm / cm 2 At that time, ethylene glycol monobutyl ether was added for adjustment. 2.23 g was added. The electrophoresis time was set as: 30 seconds soft start + 150 seconds electrophoresis time. When the film thickness was 20 microns, the voltage was 150V.

[0135] Connect the positive pole of the power supply to the anode plate, the negative pole of the power supply to two phosphide plates, and the electrostatic induction area to the induction strip. Set the voltage to: 150V; set the electrophoresis time to: 30 seconds of soft start + 150 seconds of electrophoresis time, and start preparing the electrostatic induction strip.

[0136] After electrophoresis, quickly place the electrostatic induction strip under pure water for cleaning for 10s, and let it stand in the air for 30s. Then bake it at 120°C for 20 minutes and dry it for standby for terminal paint detection.

[0137] After waiting for confirmation to end, simulate the terminal paint with the three bath solutions according to the set voltage. After the electrophoretic coating film sample is prepared, bake it at 120°C for 20 minutes and dry it for standby for terminal paint detection (that is, conduct the detection and determination of the electrostatic induction level after solvent + acid adjustment).

[0138] The detection results of the electrostatic induction level of the terminal paint for each of the above embodiments are shown in Table 1 below.

[0139] Table 1

[0140] Example Average level of normal-temperature aging Average level of solvent adjustment Average level of solvent + acid adjustment Average level Example 1 3 0 2 1.67 Example 2 5 4 5 4.7 Example 3 2 0 2 1.3 Example 4 5 1 3 3

[0141] In each of the embodiments, the electrostatic induction level is as shown in Table 1 above, mainly for simulating and comparing the terminal paint situation of the product for guiding applications. Among them, in each embodiment, to reduce experimental errors, each data in Table 1 above is the average value after 3 tests. According to the design ratio in Embodiment 1, when the average level is below 2 (including 2), there are no abnormal terminal paint problems during on-site tracking; in Embodiment 2, after significantly increasing the solid content and ash content, the level increases and there is terminal paint; in Embodiment 3, after significantly decreasing the solid content and ash content, although the level can meet the requirements, too many additives are added, making it difficult to meet on-site management; in Embodiment 4, when using different series of electrophoretic coatings for comparison, there are abnormalities in normal-temperature electrophoresis, but it quickly recovers after adding solvent. However, when simulating the on-site solvent + acid adjustment, the level rises again, with too much change and instability, making it difficult to meet customer requirements.

[0142] Using this method, it has been promoted among compressor-related customers. After determining the compressor film with low risk of terminal paint through the technical solution of the present invention, no adverse feedback regarding terminal paint has been received from customers. Before mass application, the electrostatic induction situation can be accurately predicted, improving production efficiency and product yield.

[0143] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, based on the above description, other different forms of changes or variations can be made. It is impossible to list all the implementation manners here. Any obvious changes or variations derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. A method for detecting the risk of terminal paint on a compressor during film coating, characterized in that, it includes the following steps: 1) Set an electrostatic induction device in the electrophoresis tank, and the electrostatic induction device is provided with an electrostatic induction strip; 2) During the set electrophoresis time t1, test the voltage corresponding to when the film reaches the set film thickness after the emulsion color paste is electrophoretically coated, and record it as V1; 3) Place the emulsion color paste in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V1, perform electrophoretic coating, wash, dry the electrostatic induction strip after coating, and bake it at the curing temperature of the emulsion color paste to confirm the electrostatic induction level of the electrostatic induction strip; 4) According to actual needs, add a regulator to the emulsion color paste. During the set electrophoresis time t1, test the voltage corresponding to when the film reaches the aforementioned set film thickness after the emulsion color paste is electrophoretically coated, and record it as V2; 5) Place the emulsion color paste added with the regulator in step 4) in the electrophoresis tank, set the electrophoresis time to t1 and the voltage to V2, perform electrophoretic coating, wash, dry the electrostatic induction strip after coating, and bake it at the curing temperature of the emulsion color paste added with the regulator to confirm the electrostatic induction level of the electrostatic induction strip at this time; 6) Judge the risk of terminal paint on the compressor according to the electrostatic induction levels obtained in step 3) and step 5).

2. The method according to claim 1, characterized in that, the emulsion color paste is aged and filtered before use; Preferably, the mass lost after aging in the emulsion color paste is made up with water.

3. The method according to claim 1, characterized in that, before performing step 4), it also includes repeating the steps of step 2) and step 3) multiple times, and finally determining the electrostatic induction level of the electrostatic induction strip with the average value of the electrostatic induction levels of the electrostatic induction strip each time.

4. The method according to claim 1, characterized in that, before performing step 6), it also includes repeating the steps of step 4) and step 5) multiple times, and finally determining the electrostatic induction level of the electrostatic induction strip with the average value of the electrostatic induction levels of the electrostatic induction strip each time.

5. The method according to claim 1, characterized in that, in step 1), in the electrophoresis tank, the electrostatic induction device is located in the middle area of the electrophoresis tank.

6. The method according to claim 1 or 5, characterized in that, the material of the electrostatic induction device is fiber reinforced plastic (FRP) or the electrostatic induction device is a device without ion precipitation; and / or the material of the electrostatic induction strip is tin-plated steel sheet.

7. The method according to claim 1, characterized in that, in step 1), in the electrophoresis tank, the positive electrode of the power supply is connected to the anode plate, and the negative electrode of the power supply is connected to two phosphating plates.

8. The method according to claim 1, characterized in that, the solid content of the emulsion color paste is 15 - 20%, and the ash content is 13 - 16%.

9. The method according to claim 1, characterized in that, in step 6), the method for judging the risk of terminal paint on the compressor includes the following steps: Take the average value of the sum of the electrostatic induction levels obtained in step 3) and step 5), and record it as S1; If S1 > 2, it is determined that the risk is relatively large; If S1 ≤ 2, it is determined that the risk is controllable.

10. The method according to claim 1 or 9, characterized in that, the method for setting the static induction level is as follows: set the length of the static induction bar immersed in the emulsion color paste to be h; if there is no coating attached to the static induction bar, the level is 0; if there is coating attached to a length of less than (3 / 13)h on the static induction bar, the level is 1; if there is coating attached to a length of more than (3 / 13)h and less than (6 / 13)h in the length perpendicular to the electrophoresis direction on the static induction bar, the level is 2; if there is coating attached to a length of more than (6 / 13)h and less than (11 / 13)h in the length perpendicular to the electrophoresis direction on the static induction bar, the level is 3; if there is coating attached to a length of more than (11 / 13)h and less than h in the length perpendicular to the electrophoresis direction on the static induction bar, the level is 4.

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